FN Clarivate Analytics Web of Science VR 1.0 PT J AU Chen, KY Zhang, J Muneer, MA Xue, K Niu, HS Ji, BM AF Chen, Keyu Zhang, Jing Muneer, Muhammad Atif Xue, Kai Niu, Haishan Ji, Baoming TI Plant community and soil available nutrients drive arbuscular mycorrhizal fungal community shifts during alpine meadow degradation SO FUNGAL ECOLOGY DT Article AB Arbuscular mycorrhizal fungi (AMF) play an important role in maintaining the function and sustainability of grassland ecosystem, but they are also susceptible to environmental changes. In recent decades, alpine meadows on the Tibetan Plateau have experienced severe degradation due to the impact of human activities and climate change. But it remains unclear how degradation affects the AMF community, a group of functionally important root associated microorganisms, which potentially limit the development and application of microbial tech-nologies in the restoration of degraded grasslands. In this study, we investigated AMF communities richness and composition in non-degraded (ND), moderately degraded (MD) and severely degraded (SD) alpine meadows on the Tibetan Plateau, and then explored their main biotic and abiotic determinants. Alpine meadow degradation significantly reduced plant community biomass, richness, soil organic carbon, total nitrogen, total phosphorus, available nitrogen and available phosphorus, but increased soil pH. AMF community composition and the ies-dominant family and genera differed significantly among different degradation stages. Grassland degradation shifted the AMF community composition in favor of Claroideoglomus over Rhizophagus, and resulted in a marked loss of Glomeraceae and the dominance of Diversisporaceae. Alpine meadow degradation significantly increased AMF hyphal density and richness, likely working as a plant strategy to relieve nutrient deficiencies or loss as a result of degradation. The structural equation model showed that AMF community richness and composition were significantly influenced by plant community, followed by soil available nutrients. Soil available nutrients was the key contributor to the increased AMF hyphal density and richness during grassland degradation. Our findings identify the effects of alpine meadow degradation on AMF richness and highlight the importance of the plant community in shaping the AMF community during alpine meadow degradation. These results suggest that plant community restoration should be the primary goal for the ecological restoration of degraded alpine meadows, and these soil functional microorganisms should be simultaneously integrated into ecological resto-ration strategies and management. C1 [Chen, Keyu; Zhang, Jing; Muneer, Muhammad Atif; Ji, Baoming] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. [Xue, Kai; Niu, Haishan] Univ Chinese Acad Sci, Coll Resource & Environm, Beijing 100049, Peoples R China. RP Zhang, J (通讯作者)，Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. EM zhangjing_2019@bjfu.edu.cn TC 0 Z9 0 PD APR PY 2023 VL 62 AR 101211 DI 10.1016/j.funeco.2022.101211 UT WOS:000896668400002 DA 2023-03-23 ER PT J AU Lin, HH Duan, XW Dong, YF Zhong, RH Rong, L Huang, JC AF Lin, Honghong Duan, Xingwu Dong, Yifan Zhong, Ronghua Rong, Li Huang, Jiangcheng TI Responses of soil water-holding capacity to environmental changes in alpine ecosystems across the southern Tibetan Plateau in the past 35-40 years SO CATENA DT Article AB Environmental changes on the Tibetan Plateau could affect not only the livelihoods of local people but also the food and environmental security of downstream people. Soil water-holding capacity (WHC) governs soil func-tioning in ecosystems, could be significantly altered by the accelerated climate change and vegetation degra-dation experienced by the Tibetan Plateau's alpine ecosystem. However, it remains unclear regarding the direction and magnitude of this feedback. Here, we assessed the responses of WHC to the combined impacts of climate change and vegetation degradation across the Tibetan Plateau over the past decades based on a regional resampling campaign, including 148 well-matched sampling sites, conducted in the 1980s and 2020. We observed an overall decrease in the WHC in the study area in response to a warmer climate and increased soil erosion. The decrease in the topsoil (notably 0-20 cm) was more significant than that in the subsoil (notably 20-50 cm). Average soil available water content (AWC) decreased from 0.13 to 0.10 cm3 cm-3 (p < 0.0001) for topsoil, and from 0.10 to 0.09 cm3 cm-3 (p < 0.01) for subsoil. The changes in AWC were primarily explained by soil erosion (11.3 %) and climate change (9.2 %). Furthermore, the decline in AWC results in a significant decrease in soil productivity, which may exacerbate vegetation degradation and increase the susceptibility of alpine ecosystems to disturbances. These findings suggest that soil erosion control is still an urgent task for environmental protection on the Tibetan Plateau and that increasing WHC is an important goal of adaptation measures. C1 [Lin, Honghong; Duan, Xingwu; Dong, Yifan; Zhong, Ronghua; Rong, Li; Huang, Jiangcheng] Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming 650091, Peoples R China. [Duan, Xingwu; Dong, Yifan; Zhong, Ronghua; Rong, Li; Huang, Jiangcheng] Yunnan Univ, Yunnan Key Lab Int Rivers & Transboundary Ecosecur, Kunming 650091, Peoples R China. RP Duan, XW (通讯作者)，Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming 650091, Peoples R China. EM xwduan@ynu.edu.cn TC 0 Z9 0 PD MAR PY 2023 VL 222 AR 106840 DI 10.1016/j.catena.2022.106840 UT WOS:000906009100001 DA 2023-03-23 ER PT J AU Zhang, YJ Ding, MJ Zhang, H Wang, NY Yu, ZP Xu, H Huang, P AF Zhang, Yueju Ding, Mingjun Zhang, Hua Wang, Nengyu Yu, Ziping Xu, Huan Huang, Peng TI Degradation-driven bacterial homogenization closely associated with the loss of soil multifunctionality in alpine meadows SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Alpine meadows are sensitive to climate change due to their unique ecosystem. The mechanisms by which soil microbial diversity regulates soil multifunctionality under degradation need to be extensively explored. In this study, three degraded levels of alpine meadows (nondegraded, ND; moderately degraded, MD; and severely degraded, SD) were chosen in the hinterland of Sanjiangyuan National Park on the Qinghai-Tibet Plateau. Soil microbial abundance and community structure were determined through 16 S rRNA, and six soil variables related to nutrient pools (DNA concentration, CDNA; soil organic matter, SOM; total N, TN; total P, TP; hy-drolytic N, HN; and available P, AP) were measured and calculated for soil multifunctionality. The results showed that meadow degradation resulted in a decline in bacterial functional diversity and an increase in compositional diversity (Shannon index and richness). Soil fungi were less sensitive to meadow degradation. Meanwhile, soil individual functions, such as SOM, TN, HN, AP, and multifunctionality, decreased significantly when subjected to meadow degradation. Moreover, bacterial functional diversity and the Shannon index, rather than bacterial richness, had significantly positive and negative relationships with soil multifunctionality, respectively. Furthermore, the dissimilarity of bacterial communities decreased with degradation. These results indicated that meadow degradation led to bacterial homogenization and functional redundancy, all of which would reduce soil multifunctionality. Abiotic factors such as soil water content (SWC) and bulk density (BD) also significantly changed and still played a key role in regulating the soil multifunctionality accompanying degra-dation. Amino-acid metabolism had the highest relative abundance (4.37%) and was negatively correlated with SOM and TN, implying that bacteria may convert more limited resources for their own needs and increase the loss of soil multifunctionality under severe degradation. The results provide new insight into the relationships between biodiversity and ecosystem multifunctionality and scientific guidance for the restoration of degraded alpine meadows. C1 [Zhang, Yueju; Ding, Mingjun; Zhang, Hua; Wang, Nengyu; Yu, Ziping; Xu, Huan; Huang, Peng] Jiangxi Normal Univ, Sch Geog & Environm, Key Lab Poyang Lake Wetland & Watershed Res, Minist Educ, 99 Ziyang Rd, Nanchang 330022, Peoples R China. [Ding, Mingjun; Zhang, Hua] Jiangxi Normal Univ, Jiangxi Prov Key Lab Poyang Lake Comprehens Manage, Nanchang 330022, Peoples R China. RP Zhang, H (通讯作者)，Jiangxi Normal Univ, Sch Geog & Environm, Key Lab Poyang Lake Wetland & Watershed Res, Minist Educ, 99 Ziyang Rd, Nanchang 330022, Peoples R China. EM zhangh2013@jxnu.edu.cn TC 0 Z9 0 PD MAR 1 PY 2023 VL 344 AR 108284 DI 10.1016/j.agee.2022.108284 UT WOS:000899210900006 DA 2023-03-23 ER PT J AU Duan, ZH Quan, XL Chen, MC Shi, HL Wang, ZQ Li, XQ Qiao, YM AF Duan, Zhonghua Quan, Xiaolong Chen, Mengci Shi, Huilan Wang, Zhanqing Li, Xiaoqing Qiao, Youming TI Compositional characteristics and indication of n-fatty acids in alpine meadow plants and soils SO BIOCHEMICAL SYSTEMATICS AND ECOLOGY DT Article AB Aim: To explore the distributions and indication of n-fatty acids in the plants and soils from alpine meadow, and how n-fatty acids in plants and soils are associated.Methods: The plant (grass, herb, and shrub) and soil samples were collected from alpine meadow in the Qinghai -Tibet Plateau, and the compositional characteristics of n-fatty acids were analyzed using GC-MS.Results and conclusion: n-Fatty acids ranging from C6 to C28 were identified, C16 was the most abundant fatty acid in most plants, which contributed between 39.1% and 74.2% to total n-fatty acids; the most abundant fatty acid in soils was C15, which contributed between 72.1% and 89.1% to total n-fatty acid. The total n-fatty acid content of Artemisia hedinii and the long chain n-fatty acid content of Ajuga lupulina were the highest, while the total and long chain n-fatty acid content of Saxifraga tangutica were the lowest. The contents of C20, C22, C24 and C26 in indicative plants of degradation and typical dominant plants (Festuca sinensis, Elymus nutans, Poa crymophila, Kobresia humulis, Kobresia pygmaea) were higher than other long chain n-fatty acids (C >= 20). The n-fatty acids content of the plants in degraded alpine meadow were higher than that in non-degraded alpine meadow except C6, C23, C25 and C27. The total n-fatty acids content of plants and soils in degraded alpine meadow were higher than that of non-degraded meadow. The n-fatty acids content in soils were decreased with the increasing depth of sampling except C15. The positive correlation of long chain n-fatty acids content in soils and plants was strongly significant (p < 0.001, R2 = 0.926). The compositional characteristics of n-fatty acids in plants and soils were similar. Therefore, the source of the long chain n-fatty acids in the soil might be deduced from native vegetation. C1 [Duan, Zhonghua; Quan, Xiaolong; Chen, Mengci; Qiao, Youming] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Duan, Zhonghua; Shi, Huilan; Wang, Zhanqing] Qinghai Univ, Coll Ecol Environm Engn, Xining 810016, Peoples R China. [Li, Xiaoqing] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. RP Qiao, YM (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. EM ymqiao@aliyun.com TC 0 Z9 0 PD APR PY 2023 VL 107 AR 104613 DI 10.1016/j.bse.2023.104613 EA FEB 2023 UT WOS:000942828800001 DA 2023-03-23 ER PT J AU Ma, T Yang, ZY Shi, BW Gao, WJ Li, YF Zhu, JX He, JS AF Ma, Tian Yang, Zhiying Shi, Biwan Gao, Wenjing Li, Yifan Zhu, Jianxiao He, Jin-Sheng TI Phosphorus supply suppressed microbial necromass but stimulated plant lignin phenols accumulation in soils of alpine grassland on the Tibetan Plateau SO GEODERMA DT Article AB Increased nitrogen (N) and phosphorus (P) inputs have fundamental effects on the soil organic carbon (SOC) composition and dynamics. However, the responses of plant-and microbial-derived SOC components to N and P addition in alpine grasslands are poorly understood. Based on a 10-year N and P addition experiment conducted in the alpine grassland of the Tibetan Plateau, we used amino sugars and lignin phenols as tracers for microbial necromass and plant lignin components, respectively, and explored their accumulation with the addition of N and P. We found that P and N + P addition (P supply) decreased microbial necromass, whereas N addition did not have a significant effect. In comparison, the P supply increased lignin phenols in the topsoil, but N addition decreased them in the subsoil. Among these factors, soil total P played a non-negligible role in controlling the accumulation of amino sugars and lignin phenols in soils. In addition, decreased ratios of fungi-to-bacteria necromass carbon and amino sugars to lignin phenols were observed with P supply. This implies that although the 10-year P supply did not change the SOC significantly, it may have eventually increased the SOC loss potential. Collectively, we attempted to elucidate the underlying mechanisms of long-term SOC sequestra-tion, which has important implications for plant-and microbial-mediated carbon processes in the context of increasing N and P inputs. C1 [Ma, Tian; Yang, Zhiying; Shi, Biwan; Gao, Wenjing; Li, Yifan; Zhu, Jianxiao; He, Jin-Sheng] Lanzhou Univ, State Key Lab Grassland & Agroecosystems, Lanzhou 730020, Peoples R China. [Ma, Tian; Yang, Zhiying; Shi, Biwan; Gao, Wenjing; Li, Yifan; Zhu, Jianxiao; He, Jin-Sheng] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. [Ma, Tian] Lanzhou Univ, Observat & Res Stn Ecoenvironm Frozen Ground Qilia, Lanzhou 730020, Peoples R China. RP Ma, T (通讯作者)，Lanzhou Univ, State Key Lab Grassland & Agroecosystems, Lanzhou 730020, Peoples R China.; Ma, T (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. EM matian4022@126.com TC 0 Z9 0 PD MAR PY 2023 VL 431 AR 116376 DI 10.1016/j.geoderma.2023.116376 EA FEB 2023 UT WOS:000934102400001 DA 2023-03-23 ER PT J AU Zhang, SD Wu, T Guo, L Zou, HT Shi, Y AF Zhang, Shidong Wu, Tong Guo, Luo Zou, Huiting Shi, Yu TI Integrating ecosystem services supply and demand on the Qinghai-Tibetan Plateau using scarcity value assessment SO ECOLOGICAL INDICATORS DT Article AB As a result of the land degradation it causes, rapid urbanization can severely impact the form and function of the natural environment. Because of the limited availability of natural capital and the ecosystem services they provide in many regions, fluctuations in supply and demand should rigorously considered in decision-making. The Qinghai-Tibetan Plateau (QTP) is a globally-important ecoregion that generates significant ecosystem ser-vices value. Focusing on the QTP, we calculated the value change in the supply of ecosystem services using a coefficient table and the change in demand based on population, GDP, and income elasticity. The impact of supply and demand on the scarcity value of ecosystem services (ESSV) was then compared across four repre-sentative scenarios. The results showed that the ESSV on the QTP rose considerably between 1990 and 2020, particularly between 2000 and 2010. Between 1990 and 2020, the public-goods services grew faster than private -goods services. The most important element impacting the ESSV was demand-driven scarcity. The level of ur-banization gradually increased during 1990-2020, with a consistent distribution of high ESSV and high ur-banization across the region. High-High types and Low-Low types had a significant aggregation effect, located primarily in the north and west of the QTP, respectively. The Low-High type was scattered along with the Low -Low type, indicating fragile ecological conditions that merit greater protection from land degradation. The de-gree of coupling reveals an increasing degree of synergy between ESSV and urbanization on the QTP, indicating potential for more synergistic development. C1 [Zhang, Shidong; Guo, Luo; Zou, Huiting; Shi, Yu] Minzu Univ China, Coll Life & Environm Sci, Beijing 100081, Peoples R China. [Wu, Tong] Stanford Univ, Nat Capital Project, Stanford, CA 94301 USA. RP Guo, L (通讯作者)，Minzu Univ China, Coll Life & Environm Sci, Beijing 100081, Peoples R China.; Wu, T (通讯作者)，Stanford Univ, Nat Capital Project, Stanford, CA 94301 USA. EM 21400281@muc.edu.cn; tongwu@stanford.edu; guoluo@muc.edu.cn; 20302112@muc.edu.cn; 19301381@muc.edu.cn TC 0 Z9 0 PD MAR PY 2023 VL 147 AR 109969 DI 10.1016/j.ecolind.2023.109969 EA FEB 2023 UT WOS:000931875800001 DA 2023-03-23 ER PT J AU Lv, YY Sun, Y Yi, SH Meng, BP AF Lv, Yanyan Sun, Yi Yi, Shuhua Meng, Baoping TI Human activities dominant the distribution of Kobresia pygmaea community in alpine meadow grassland in the east source region of Yellow River, China SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Kobresia pygmaea is the endemic and one of the most important species in the alpine meadow in the Qinghai-Tibet Plateau. It is the key stage in the management of degraded grassland, and irreversible degradation will take place after the degradation succession phases of the Kobresia pygmaea community. However, knowledge about the spatial distribution and driving factors were still unknown. In this study, the potential distribution of the Kobresia pygmaea community was determined using the BIOMOD niche model. Combine with the reality distribution based on remote sensing classification, the driving factors of climate and human activities were identified. The findings revealed that: (1) among all environmental factors, the maximum radiation, monthly temperature difference, driest period precipitation were the main climate influencing factors for the Kobresia pygmaea community distribution, and random forest model achieved the highest prediction accuracy and best stability of any niche model. (2) The potential distribution area of Kobresia pygmaea community was 653.25 km(2) (account for 3.28% of the study area), and mostly located in northern and central of Zeku County, northeast of Henan County, and northeast, central, and eastern parts of Maqu County. (3) Climate factors driven 21.12% of Kobresia pygmaea community reality distribution, while human activities driven for 79.98%. Our results revealed that human activities dominant the reality distribution of Kobresia pygmaea community in alpine meadow grassland in the east source region of Yellow River, China. C1 [Lv, Yanyan; Sun, Yi; Yi, Shuhua; Meng, Baoping] Nantong Univ, Inst Fragile Eco Environm, Nantong, Jiangsu, Peoples R China. [Lv, Yanyan; Sun, Yi; Yi, Shuhua; Meng, Baoping] Nantong Univ, Sch Geog Sci, Nantong, Jiangsu, Peoples R China. RP Meng, BP (通讯作者)，Nantong Univ, Inst Fragile Eco Environm, Nantong, Jiangsu, Peoples R China.; Meng, BP (通讯作者)，Nantong Univ, Sch Geog Sci, Nantong, Jiangsu, Peoples R China. EM mengbp18@ntu.edu.cn TC 0 Z9 0 PD FEB 2 PY 2023 VL 11 AR 1127973 DI 10.3389/fevo.2023.1127973 UT WOS:000937249900001 DA 2023-03-23 ER PT J AU Guo, N Sang, C Huang, M Zhang, R Degen, AA Ma, LN Bai, YF Zhang, T Wang, WY Niu, JH Li, SS Long, RJ Shang, ZH AF Guo, Na Sang, Chao Huang, Mei Zhang, Rui Degen, A. Allan Ma, Lina Bai, Yanfu Zhang, Tao Wang, Wenyin Niu, Jiahuan Li, Shanshan Long, Ruijun Shang, Zhanhuan TI Long-term active restoration of degraded grasslands enhances vegetation resilience by altering the soil seed bank SO AGRONOMY FOR SUSTAINABLE DEVELOPMENT DT Article AB Long-term active restoration is often employed to restore degraded grasslands. The establishment of a viable soil seed bank is the key to successful restoration, as it enhances the resilience of vegetation. However, little is known of how the soil seed bank affects vegetation resilience following long-term active restoration of degraded grasslands. We determined seed abundance and species composition of the soil seed bank and soil properties and vegetation resilience of intact, degraded, and long-term (> 10 years) actively restored grasslands on the Tibetan plateau (3900-4200 m a.s.l.). The plant-soil-seed bank quality index and structural equation modelling (SEM) were used to assess the effect of the soil seed bank on vegetation resilience. After long-term (> 10 years) active restoration of degraded grasslands by sowing seeds of native plant species, the densities of transient and persistent seeds increased by 5%, but seed richness (number of species) decreased by 25% when compared with degraded grasslands. This occurred largely as a result of an increase in grass but decrease in forb seeds. Persistent seeds of grasses play an important role in the productivity of restored grasslands, while the density of persistent seeds serves as an indicator of the resilience of vegetation. A combination of the plant community and soil properties determined seed density. Here, we show for the first time that long-term active restoration enhances vegetation resilience of grasslands by altering the soil seed bank. A high seed density of sown Gramineae and a low seed density of forbs in the soil seed bank is a key to the successful active restoration of degraded grasslands. C1 [Guo, Na; Sang, Chao; Huang, Mei; Ma, Lina; Bai, Yanfu; Zhang, Tao; Wang, Wenyin; Niu, Jiahuan; Li, Shanshan; Long, Ruijun; Shang, Zhanhuan] Lanzhou Univ, Coll Ecol, State Key Lab Herbage Improvement & Grassland Agro, Lanzhou 730000, Peoples R China. [Zhang, Rui] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Urat Desert Grassland Res Stn, Lanzhou 730000, Peoples R China. [Degen, A. Allan] Ben Gurion Univ Negev, Jacob Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, IL-8410500 Beer Sheva, Israel. [Bai, Yanfu] Sichuan Agr Univ, Coll Grassland Sci & Technol, Chengdu 611130, Peoples R China. [Niu, Jiahuan] Xian Jiaotong Liverpool Univ, Dept Hlth & Environm Sci, Suzhou 215123, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Coll Ecol, State Key Lab Herbage Improvement & Grassland Agro, Lanzhou 730000, Peoples R China. EM shangzhh@lzu.edu.cn TC 0 Z9 0 PD FEB PY 2023 VL 43 IS 1 AR 6 DI 10.1007/s13593-022-00862-9 UT WOS:000907155100001 DA 2023-03-23 ER PT J AU Huang, XM Shi, JT Sun, WY Sun, CM Shen, XP AF Huang, Xiaomin Shi, Jingtao Sun, Wenyuan Sun, Chengming Shen, Xinping TI Cultivation in an Alpine Region: Implications for Soil Bacteria SO AGRONOMY-BASEL DT Article AB Land use change is a major predictor for variations in soil bacteria, which plays a key role in maintaining soil multifunctionality and function of terrestrial ecosystems. The effects of land use change on the soil bacterial community in an alpine region at the Qinghai-Tibetan Plateau (QTP) were still unclear. In this study, we investigated soil bacterial profiles under grazed grassland, enclosed grassland, continuous cropland, rotation cropland and abandoned cropland in the Tianzhu alpine agro-pastoral ecotone. Our results showed that Proteobacteria, Acidobacteria and Actinobacteria were the most three abundant phyla regardless of land use change, accounting for over 60% of the total. Cultivation declined soil bacterial alpha diversity without recovering even after abandonment. Over 73% variations in bacterial diversity can be explained by soil physical and chemical properties. In addition, soil moisture could be the main driver for the difference in bacterial structure between croplands and others. Soil bulk density, pH, organic carbon and total nitrogen contents seem to be the key factors determining the difference in bacterial structure between abandoned croplands and others. Our results have implications for comprehensive understanding about the responses of the soil bacterial community to land use change in alpine regions. C1 [Huang, Xiaomin; Shi, Jingtao; Sun, Chengming; Shen, Xinping] Yangzhou Univ, Agr Coll, Jiangsu Key Lab Crop Genet & Physiol, Jiangsu Key Lab Crop Cultivat & Physiol, Yangzhou 225009, Peoples R China. [Huang, Xiaomin; Shi, Jingtao; Sun, Chengming; Shen, Xinping] Yangzhou Univ, Jiangsu Coinnovat Ctr Modern Prod Technol Grain Cr, Yangzhou 225009, Peoples R China. [Huang, Xiaomin; Shi, Jingtao; Shen, Xinping] Yangzhou Univ, Modern Agr Dev Res Inst Co Ltd, Changshu 215551, Peoples R China. [Sun, Wenyuan] Changshu Water Conservancy Technol Promot Stn, Changshu 215500, Peoples R China. RP Sun, CM; Shen, XP (通讯作者)，Yangzhou Univ, Agr Coll, Jiangsu Key Lab Crop Genet & Physiol, Jiangsu Key Lab Crop Cultivat & Physiol, Yangzhou 225009, Peoples R China.; Sun, CM; Shen, XP (通讯作者)，Yangzhou Univ, Jiangsu Coinnovat Ctr Modern Prod Technol Grain Cr, Yangzhou 225009, Peoples R China.; Shen, XP (通讯作者)，Yangzhou Univ, Modern Agr Dev Res Inst Co Ltd, Changshu 215551, Peoples R China. EM cmsun@yzu.edu.cn; xpshen@yzu.edu.cn TC 0 Z9 0 PD FEB PY 2023 VL 13 IS 2 AR 296 DI 10.3390/agronomy13020296 UT WOS:000938082700001 DA 2023-03-23 ER PT J AU Liu, W Yuan, YC Li, Y Li, R Jiang, YH AF Liu, Wei Yuan, Yecheng Li, Ying Li, Rui Jiang, Yuhao TI Net Primary Productivity Estimation Using a Modified MOD17A3 Model in the Three-River Headwaters Region SO AGRONOMY-BASEL DT Article AB Remote sensing (RS) models can easily estimate the net primary productivity (NPP) on a large scale. The majority of RS models try to couple the effects of temperature, water, stand age, and CO2 concentration to attenuate the maximum light use efficiency (LUE) in the NPP models. The water effect is considered the most unpredictable, significant, and challenging. Because the stomata of alpine plants are less sensitive to limiting water vapor loss, the typically employed atmospheric moisture deficit or canopy water content may be less sensitive in signaling water stress on plant photosynthesis. This study introduces a soil moisture (SM) content index and an alpine vegetation photosynthesis model (AVPM) to quantify the RS NPP for the alpine ecosystem over the Three-River Headwaters (TRH) region. The SM content index was based on the minimum relative humidity and maximum vapor pressure deficit during the noon, and the AVPM model was based on the framework of a moderate resolution imaging spectroradiometer NPP (MOD17) model. A case study was conducted in the TRH region, covering an area of approximately 36.3 x 10(4) km(2). The results demonstrated that the AVPM NPP greatly outperformed the MOD17 and had superior accuracy. Compared with the MOD17, the average bias of the AVPM was -9.8 gCm(-2)yr(-1), which was reduced by 91.8%. The average mean absolute percent error was 57.0%, which was reduced by 68.2%. The average Pearson's correlation coefficient was 0.4809, which was improved by 30.0%. The improvements in the NPP estimation were mainly attributed to the decreasing estimation of the water stress coefficient on the NPP, which was considered the higher constraint of water impact on plant photosynthesis. Therefore, the AVPM model is more accurate in estimating the NPP for the alpine ecosystem. This is of great significance for accurately assessing the vegetation growth of alpine ecosystems across the entire Qinghai-Tibet Plateau in the context of grassland degradation and black soil beach management. C1 [Liu, Wei; Yuan, Yecheng; Li, Ying; Li, Rui] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China. [Liu, Wei; Li, Ying; Li, Rui] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Jiang, Yuhao] Natl Forestry & Grassland Adm, Acad Forest Inventory & Planning, Beijing 100013, Peoples R China. RP Yuan, YC (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China. EM yuanyc@lreis.ac.cn TC 0 Z9 0 PD FEB PY 2023 VL 13 IS 2 AR 431 DI 10.3390/agronomy13020431 UT WOS:000937933500001 DA 2023-03-23 ER PT J AU Su, JH Ji, WH Sun, XM Wang, HF Kang, YK Yao, BH AF Su, Junhu Ji, Weihong Sun, Xiaomei Wang, Haifang Kang, Yukun Yao, Baohui TI Effects of different management practices on soil microbial community structure and function in alpine grassland SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Management practices, such as grazing exclusion and reseeding, have been implemented to mitigate the degradation of grassland. Low grazing intensities and reseeding increase grass production. Nevertheless, few studies have investigated the effects of these measures on the soil microbial community structure and function in the Qinghai Tibetan Plateau (QTP). To reveal the effects of management practices on soil microbes and give a reference to assess and improve ecosystems functions, we here evaluated the impact of various types of grazing (exclusion, seasonal, and traditional), reseeding (annual oat (Avena fatua) grassland (RO) and perennial artificial grassland cultivated >10 y), and integrated restoration (weed control and no-tillage reseeding) measures on soil microbial community structure and function in the QTP. The Shannon-Wiener diversity indices were highest for prokaryotes under RO and for fungi under integrated grassland restoration. Relative Actinobacteria abundance was higher under seasonal grazing than that under integrated grassland restoration. The latter had relatively higher abundances of Betaproteobacteria, Alphaproteobacteria, and Deltaproteobacteria and comparatively lower abundance of Thermoleophilia. There were significantly higher abundances of plant pathogens under seasonal grazing than those under other managements. There were significantly high proportions of pathotrophs and saprotrophs (10.0%) under seasonal and traditional grazing, respectively. The proportion of pathotrophs under integrated restoration (10.0%) was about seven-fold greater than that under grazing exclusion (1.5%). The relative differences among treatments in terms of soil water content, plant biomass, and soil C:N partially explained the differences in their prokaryotic community compositions. Increases in soil organic carbon and C:N may explain the observed changes in the soil fungal communities. The management practices affected soil microorganisms mainly by altering the soil nutrient profile. Grazing attracted specific pathotrophs and saprotrophs while repelling certain plant pathogens. Hence, modulations in soil microbial community structure and function must be considered in the process of planning for the implementation of grassland degradation management measures. C1 [Su, Junhu; Kang, Yukun; Yao, Baohui] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Peoples R China. [Su, Junhu; Ji, Weihong; Sun, Xiaomei; Wang, Haifang; Kang, Yukun; Yao, Baohui] Gansu Agr Univ, Massey Univ Res Ctr Grassland Biodivers, Gansu Agr Univ, Lanzhou 730070, Peoples R China. [Su, Junhu; Kang, Yukun; Yao, Baohui] Gansu Qilianshan Grassland Ecosyst Observat & Res, Wuwei 733200, Peoples R China. [Ji, Weihong] Massey Univ, Inst Nat & Math Sci, Private Bag,North Shore Mail Ctr 0632,102 904rad, Auckland 0632, New Zealand. [Sun, Xiaomei] Gansu Agr Univ, Coll Resource & Environm Sci, Lanzhou 730070, Peoples R China. [Wang, Haifang] Gansu Agr Univ, Coll Life Sci & Technol, Lanzhou 730070, Peoples R China. RP Su, JH (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Peoples R China. EM sujh@gsau.edu.cn TC 0 Z9 0 PD FEB 1 PY 2023 VL 327 AR 116859 DI 10.1016/j.jenvman.2022.116859 UT WOS:000900220000009 DA 2023-03-23 ER PT J AU Xing, YF Shi, JJ De, KJ Wang, XL Wang, W Ma, Y Zhang, HR He, MH Liu, QQ AF Xing, Yunfei Shi, Jianjun De, Kejia Wang, Xiaoli Wang, Wei Ma, Yuan Zhang, Hairong He, Miaohua Liu, Qingqing TI The Current Distribution of Carex alatauensis in the Qinghai-Tibet Plateau Estimated by MaxEnt SO AGRONOMY-BASEL DT Article AB Modeling the current distribution of and predicting suitable habitats for threatened species support the species conservation and restoration planning process. Therefore, the purpose of this study was to model the actual distribution and predict environmentally suitable habitats for Carex alatauensis S.R.Zhang 2015, a locally threatened native grass species on the Qinghai-Tibet Plateau. To realize this objective, based on the geographical samples within the natural distribution of C. alatauensis, the dominant climatic factors in its potential distribution range were analyzed using the maximum entropy (MaxEnt) model. The results showed that the average values of the area under the receiver operating characteristic curve (AUC) of the training data were 0.833 +/- 0.044, which indicated that the accuracy of the MaxEnt model was pretty high for modeling potential distribution regions of C. alatauensis. The combined results from the Jackknife test and the presented contribution of environmental variables revealed that the annual precipitation, the growth season precipitation, and the precipitation of the driest month were the key climatic factors that restricted the distribution of C. alatauensis on the Qinghai-Tibet Plateau. It is predicted that the potential distribution area of C. alatauensis on the Qinghai-Tibet Plateau is 1.96 x 10(6) km(2), and the most suitable area is 3.7 x 10(5) km(2), mainly located in the Qilian Mountains, the Himalayas, and the Qingtanggula Mountains. C1 [Xing, Yunfei; Shi, Jianjun; De, Kejia; Wang, Xiaoli; Wang, Wei; Ma, Yuan; Zhang, Hairong; He, Miaohua; Liu, Qingqing] Qinghai Univ, Agr & Anim Husb Coll, Xining 810016, Peoples R China. [Xing, Yunfei; Shi, Jianjun; De, Kejia; Wang, Xiaoli; Wang, Wei; Ma, Yuan] Qinghai Acad Anim Sci & Vet Med, Xining 810018, Peoples R China. [Xing, Yunfei; Shi, Jianjun] Minist Educ Key, Lab Alpine Grassland Ecol Three River Source Reg, Xining 810016, Peoples R China. [Shi, Jianjun] Qinghai Prov Key Lab Adapt Management Alpine Grass, Xining 810016, Peoples R China. RP Shi, JJ; De, KJ (通讯作者)，Qinghai Univ, Agr & Anim Husb Coll, Xining 810016, Peoples R China.; Shi, JJ; De, KJ (通讯作者)，Qinghai Acad Anim Sci & Vet Med, Xining 810018, Peoples R China.; Shi, JJ (通讯作者)，Minist Educ Key, Lab Alpine Grassland Ecol Three River Source Reg, Xining 810016, Peoples R China.; Shi, JJ (通讯作者)，Qinghai Prov Key Lab Adapt Management Alpine Grass, Xining 810016, Peoples R China. EM shjj0318@sina.com; 18090900142@qhu.edu.cn TC 0 Z9 0 PD FEB PY 2023 VL 13 IS 2 AR 564 DI 10.3390/agronomy13020564 UT WOS:000937957300001 DA 2023-03-23 ER PT J AU Zhang, CP Li, Q Feng, RQ Zhang, ZH Yang, YF Liu, J AF Zhang, Chunping Li, Qi Feng, Runqiu Zhang, Zhenhua Yang, Yunfeng Liu, Jie TI C:N:P stoichiometry of plant-soil-microbe in the secondary succession of zokor-made mounds on Qinghai-Tibet Plateau SO ENVIRONMENTAL RESEARCH DT Article AB The knowledge of ecological stoichiometry and stoichiometric homeostasis could contribute to exploring the balance of chemical elements in ecological recovery. However, it is largely unknown how the carbon (C), nitrogen (N), phosphorus (P), and stoichiometric characteristics in the plant-soil-microbe continuum system respond to the spontaneous secondary succession of degraded alpine grasslands. Therefore, we investigated the spontaneous secondary successional recovery of grasslands disturbed by zokor (Myospalax fontanierii) on the Qinghai-Tibetan Plateau, China, via a strategy of substituting space for time. Based on plant richness, biomass, and coverage, plant importance value was employed to assess the recovery degree of zokor-made mounds (ZMMs, large and bare patch areas constructed by zokors). Multiple statistical methods, including stoichiometric homeostatic model, network, and redundancy analysis, were conducted to decipher the stoichiometric patterns. The results indicated that plant C, C:N, and C:P increased with the recovery of ZMMs, contrary to the decrease of plant N and P. In addition, soil C, N, C:N, C:P, and N:P increased with the recovery degree, and the soil became relatively more N rich by increasing organic N under the revegetation of legumes. Meanwhile, soil microbial biomass C, N, and P increased with the recovery of ZMMs, but microbial biomass C:N:P ratios were highly constrained. Soil accessible inorganic nitrogen played an important role in driving plant and microbial nutrient and stoichiometry. Our results demonstrated that the different responses of C, N, and P contents in plant-soilmicrobe lead to shifts in C:N:P stoichiometric ratio. Nevertheless, plants and soil microbes exhibited strong stoichiometric homeostasis. Collectively, our study provides new insight into biogeochemical responses to the successional recovery of degraded alpine grassland on the Qinghai-Tibetan Plateau from a stoichiometric perspective. C1 [Zhang, Chunping; Li, Qi; Feng, Runqiu; Liu, Jie] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Ctr Grassland Microbiome, Collaborat Innovat Ctr Western Ecol Safety,State K, Lanzhou 730020, Peoples R China. [Liu, Jie] Nankai Univ, Minist Educ, Key Lab Pollut Proc & Environm Criteria, Tianjin 300350, Peoples R China. [Zhang, Zhenhua] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Haibei Natl Field Res Stn Alpine Grassland, Xining 810008, Peoples R China. [Zhang, Zhenhua] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Yang, Yunfeng] Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Cont, Beijing 100084, Peoples R China. [Liu, Jie] 222 TianShui Rd South, Lanzhou, Gansu, Peoples R China. RP Liu, J (通讯作者)，222 TianShui Rd South, Lanzhou, Gansu, Peoples R China. EM jieliu@lzu.edu.cn TC 0 Z9 0 PD APR 1 PY 2023 VL 222 AR 115333 DI 10.1016/j.envres.2023.115333 EA FEB 2023 UT WOS:000931592100001 DA 2023-03-23 ER PT J AU Gan, T Zhao, HW Ai, Y Zhang, SH Wen, YL Tian, LM Mipam, TD AF Gan, Tian Zhao, Hongwen Ai, Yi Zhang, Sihu Wen, Yongli Tian, Liming Mipam, Tserang Donko TI Spatial distribution and ecological risk assessment of heavy metals in alpine grasslands of the Zoige Basin, China SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Heavy metals elements are not only related to the functions of ecosystems but also affect human health. To understand the characteristics of heavy metals in the topsoil of the Zoige alpine basin, a total of 252 grass and topsoil samples were collected in May and September 2014. The results showed that only Cd and Pb highly exceeded their background values (BV); in May and September, Cd was 2.02- and 1.55-fold higher than its BV, respectively, and Pb was 2.35- and 2.17-fold above its BV, respectively. The sources of Cd and Pb were homologous. In addition, the comprehensive potential ecological risk index was less than 150, indicating that heavy metal pollution in the study area is currently low. The spatial interpolation indicated that Cd and Pb pollution might be related to tourism and transportation, but the low biological absorption coefficient for all heavy metals showed that heavy metal absorption ability of forage was low and would not impact yak breeding. Finally, the soil was lightly contaminated by Cd and Pb due to the rapid development of the animal husbandry and tourism. The spatial variation of heavy metal in the basin is dominated by structural factors, and the random factors also have an effect on spatial distribution of As, Cd, Cu and Ni. The random factors such as overgrazing can exert an influence on physical structure and the circulation of nutrient substances of meadow soil through livestock grazing and trampling, ultimately affecting the content and distribution of soil heavy metals. C1 [Gan, Tian; Ai, Yi; Zhang, Sihu; Wen, Yongli; Mipam, Tserang Donko] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Sichuan Zoige Alpine Wetland Ecosyst Natl Observat, Chengdu, Peoples R China. [Zhao, Hongwen] Sichuan Acad Grassland Sci, Chengdu, Peoples R China. [Tian, Liming] Sichuan Univ, Coll Life Sci, Sichuan Zoige Alpine Wetland Ecosyst Natl Observat, Chengdu, Peoples R China. [Tian, Liming] Sichuan Univ, Coll Life Sci, Key Lab Bioresource & Ecoenvironm, Minist Educ, Chengdu, Peoples R China. RP Mipam, TD (通讯作者)，Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Sichuan Zoige Alpine Wetland Ecosyst Natl Observat, Chengdu, Peoples R China. EM tdmipam@163.com TC 0 Z9 0 PD JAN 27 PY 2023 VL 11 AR 1093823 DI 10.3389/fevo.2023.1093823 UT WOS:000929011400001 DA 2023-03-23 ER PT J AU Wang, L Ma, WM Zhou, D Chen, Q Liu, L Li, L AF Wang, Li Ma, Wenmei Zhou, Dan Chen, Qi Liu, Lu Li, Long TI Bioclimatic drivers of forage growth and cover in alpine rangelands SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Context: Climate change and human activities have significant impacts on the Qinghai-Tibetan Plateau; the alpine ecosystem in this region has been degraded. A decline in forage yield reduces the livestock carrying capacity, but an unmitigated increase may lead to overfeeding and damage to vegetation. These changes have eventually led to grassland degradation and a series of ecological problems. Therefore, it is essential to examine bioclimatic factors that affect forage growth in grasslands.Objective: To identify bioclimatic factors associated with forage growth and coverage in the Qinghai-Tibetan Plateau.Methods: We examined how forage growth and coverage are affected by 35 bioclimatic indicators published in a global database (CMCC-BioClimInd).Results and conclusions: We comprehensively considered the relationship between 35 indicators and forage yield and coverage and found that the combination of temperature and precipitation indicators had a very high correlation with yield and coverage. When we evaluated the relationship between each index and forage yield, forage yield was found to be significantly correlated with 16 bioclimatic indices. Forage yield was positively correlated with yearly positive precipitation (R-2 = 0.49, p < 0.05), annual precipitation (R-2 = 0.48, p < 0.05), and precipitation of driest quarter (R-2 = 0.47, p < 0.05), and negatively correlated with temperature seasonality (R-2 = 0.52, p < 0.05), precipitation seasonality (R-2 = 0.39, p < 0.05), and simplified continentality index (R-2 = 0.48). Forage coverage was significantly correlated with 15 bioclimatic indicators. It showed positive correlations with precipitation of driest quarter (R-2 = 0.36, p < 0.05), precipitation of driest month (R-2 = 0.33, p < 0.05), and annual precipitation (R-2 = 0.31, p < 0.05), and negative correlations with temperature seasonality (R-2 = 0.415, p < 0.05), annual temperature range, precipitation seasonality, and simplified continentality index (R-2 = 0.37, p < 0.05).Significance: We identified bioclimatic indicators that affect forage growth in the northeastern Qinghai-Tibetan Plateau, and explored the physiological and ecological mechanisms underlying forage growth. Our results provide a scientific basis for future forage management, early determination of livestock carrying capacity, rational management of animal husbandry practices, and ecological protection and restoration efforts. C1 [Wang, Li] Inst Meteorol Sci Res Qinghai Prov, Meteorol Bur Qinghai Prov, Xining, Peoples R China. [Ma, Wenmei; Zhou, Dan; Chen, Qi; Liu, Lu] Meteorol Serv Ctr Qinghai Prov, Meteorol Bur Qinghai Prov, Xining, Peoples R China. [Li, Long] Qinghai Normal Univ, Sch Geog Sci, Xining, Peoples R China. [Li, Long] QingHai Remote Sensing Ctr Nat Resources, Xining, Peoples R China. RP Ma, WM (通讯作者)，Meteorol Serv Ctr Qinghai Prov, Meteorol Bur Qinghai Prov, Xining, Peoples R China. EM maxiaolu0607@126.com TC 0 Z9 0 PD JAN 26 PY 2023 VL 10 AR 1076005 DI 10.3389/fevo.2022.1076005 UT WOS:000934244300001 DA 2023-03-23 ER PT J AU Wang, YC Dang, N Feng, K Wang, JB Jin, X Yao, ST Wang, LL Gu, SS Zheng, H Lu, GX Deng, Y AF Wang, Yingcheng Dang, Ning Feng, Kai Wang, Junbang Jin, Xin Yao, Shiting Wang, Linlin Gu, Songsong Zheng, Hua Lu, Guangxin Deng, Ye TI Grass-microbial inter-domain ecological networks associated with alpine grassland productivity SO FRONTIERS IN MICROBIOLOGY DT Article AB Associations between grasses and soil microorganisms can strongly influence plant community structures. However, the associations between grass productivity and diversity and soil microbes, as well as the patterns of co-occurrence between grass and microbes remain unclear. Here, we surveyed grass productivity and diversity, determined soil physicochemical, and sequenced soil archaea, bacteria and fungi by metabarcoding technology at 16 alpine grasslands. Using the Distance-decay relationship, Inter-Domain Ecological Network (IDEN), and Mantel tests, we investigated the relationship between grass productivity, diversity and microbial diversity, and the patterns of co-occurrence between grass and microbial inter-domain network in alpine grassland. We found the archaea richness, bacteria richness and Shannon, and fungi alpha-diversity were significantly negatively correlation with grass diversity, but archaea and bacteria diversity were positively correlation with grass productivity. Moreover, an increase in microbial beta-diversity was observed along with increased discrepancy in grass diversity and productivity and soil variables. Variance partitioning analysis suggested that the contribution of grass productivity on microbial community was higher than that of soil variables and grass diversity, which implies that microbial community was more related to grass productivity. Inter-Domain Ecological Network showed that the grass species formed complex and stable ecological networks with some bacterial, archaeal, and fungal species, and the grass-fungal ecological networks showed the highest robustness, which indicated that soil fungi could better co-coexist with aboveground grass in alpine grasslands. Besides, the connectivity degrees of the grass-microbial network were significantly positively correlated with grass productivity, suggesting that the coexistence pattern of grasses and microbes had a positive feedback effect on the grass productivity. The results are important for establishing the regulatory mechanisms between plants and microorganisms in alpine grassland ecosystems. C1 [Wang, Yingcheng; Jin, Xin; Yao, Shiting; Lu, Guangxin] Qinghai Univ, Collage Agr & Anim Husb, Xining, Peoples R China. [Wang, Yingcheng; Feng, Kai; Wang, Linlin; Gu, Songsong; Deng, Ye] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, CAS Key Lab Environm Biotechnol, Beijing, Peoples R China. [Dang, Ning] Chinese Acad Sci, Inst Appl Ecol, Shenyang, Peoples R China. [Dang, Ning; Deng, Ye] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Wang, Junbang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Natl Ecosyst Sci Data Ctr, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China. [Wang, Linlin] Shandong Univ, Inst Marine Sci & Technol, Qingdao, Peoples R China. [Zheng, Hua] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing, Peoples R China. RP Lu, GX (通讯作者)，Qinghai Univ, Collage Agr & Anim Husb, Xining, Peoples R China.; Deng, Y (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, CAS Key Lab Environm Biotechnol, Beijing, Peoples R China.; Deng, Y (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. EM lugx74@qq.com; yedeng@rcees.ac.cn TC 0 Z9 0 PD JAN 25 PY 2023 VL 14 AR 1109128 DI 10.3389/fmicb.2023.1109128 UT WOS:000928595800001 DA 2023-03-23 ER PT J AU Jia, YL Chen, SY Wu, MH Gu, YZ Wei, PJ Wu, TH Shang, ZH Wang, SJ Yu, HY AF Jia, Yinglan Chen, Shengyun Wu, Minghui Gu, Yuzheng Wei, Peijie Wu, Tonghua Shang, Zhanhuan Wang, Shijin Yu, Hongyan TI Improved permafrost stability by revegetation in extremely degraded grassland of the Qinghai-Tibetan Plateau SO GEODERMA DT Article AB Revegetation is an effective approach for restoring extremely degraded grassland (DG) in the Qinghai-Tibetan Plateau (QTP). However, little is known about its effects on permafrost stability. Our study investigated changes in the characteristics of DG and revegetated grassland (RG) in alpine permafrost regions of the QTP by means of in situ monitoring and sampling. Compared with DG, soil temperature was lower in warm months and slightly higher in cool months both at 2 and 10 cm depths after revegetation, while soil moisture generally decreased. Revegetation advanced the onset and increased the duration of completely frozen stage. The number of freeze-thaw days decreased at 2 cm but increased at 10 cm depth. The freeze-thaw strength weakened at 2 cm depth in spring and autumn, and at 10 cm depth in autumn, but increased at 10 cm depth in spring. The thawing index at the two depths and active layer thickness in RG were also significantly lower than those in DG. Revegetation significantly affected the particle size distribution and stability of soil aggregates by increasing the proportion of large macroaggregates. Thus, revegetation can effectively improve the permafrost stability of degraded grassland in the QTP and enhance the service functions of alpine grassland ecosystems. C1 [Jia, Yinglan; Chen, Shengyun; Wu, Minghui; Gu, Yuzheng; Wei, Peijie; Wu, Tonghua] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere & Ecoenvironm Res Stn Shule River Headw, Lanzhou 730000, Gansu, Peoples R China. [Chen, Shengyun; Shang, Zhanhuan] Lanzhou Univ, Coll Ecol, State Key Lab Grassland & Agroecosystems, Lanzhou 730000, Gansu, Peoples R China. [Wang, Shijin] Natl Field Sci Observat & Res Stn Yulong Snow Mt C, Lanzhou 730000, Gansu, Peoples R China. [Chen, Shengyun; Yu, Hongyan] Long Term Natl Sci Res Base Qilian Mt Natl Pk, Xining 810000, Qinghai, Peoples R China. [Jia, Yinglan; Wu, Minghui; Wei, Peijie] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Chen, SY (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere & Ecoenvironm Res Stn Shule River Headw, Lanzhou 730000, Gansu, Peoples R China. EM sychen@lzb.ac.cn TC 0 Z9 0 PD FEB PY 2023 VL 430 AR 116350 DI 10.1016/j.geoderma.2023.116350 EA JAN 2023 UT WOS:000926308800001 DA 2023-03-23 ER PT J AU Wei, WR Yao, X Zhang, Y Zhen, QY Qin, MS Tang, ZM Oosthuizen, MK Zhang, WG AF Wei, Wanrong Yao, Xiao Zhang, Yan Zhen, Qiaoyan Qin, Minsen Tang, Zhongmin Oosthuizen, Maria K. K. Zhang, Weiguo TI Vegetation restoration measures: Increasing plant height suppresses population densities of plateau pikas SO LAND DEGRADATION & DEVELOPMENT DT Article; Early Access AB Plateau pikas (Ochotona curzoniae) are often regarded as pests when their population densities exceed a certain threshold. Vegetation restoration measures are commonly used for the ecological control of pikas. Nevertheless, it is not known how effective these measures are, and if effective, which factors are responsible for the decline in pika densities. Four commonly used grassland restoration measures: exclosure [E], exclosure/fertilized [EF], exclosure/overseeding [EO], exclosure/fertilization/over-seeding [EOF], were implemented in grasslands degraded by high densities of pikas, and the pika density (PD) and vegetation traits in each treatment plot were monitored for 4 consecutive years. Neither the PD nor the vegetation composition was affected by any of the vegetation restoration measures within the first year. From the second year onwards, all the vegetation restoration measures had a significant effect on the vegetation composition and structure, such as an increase in the height, cover, and biomass. All the vegetation restoration measures, except E, had a significant suppressive effect on pika densities as time progressed, with the combination EOF measure having the largest effect. The stepwise regression analysis indicated that the vegetation height is the main factor that determines the PD. Similarly, structural equation modelling showed that vegetation restoration measures reduce PD primarily by increasing vegetation height. This may be because the height of the vegetation is closely correlated to the predation risk of pikas. Our results highlight the importance of vegetation height in pika management, suggesting that the key to successful pika management is to find a sustainable grazing system, which is beneficial to the growth of the dominant graminoids and maintains a high plant diversity for the sustainability of grassland ecosystems. C1 [Wei, Wanrong; Zhen, Qiaoyan; Qin, Minsen] China West Normal Univ, Coll life Sci, Key Lab Southwest China Wildlife Resources Conserv, Nanchong, Peoples R China. [Wei, Wanrong; Zhang, Yan; Zhang, Weiguo] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. [Yao, Xiao] Jiangsu Prov & Chinese Acad Sci, Inst Bot, Nanjing, Peoples R China. [Tang, Zhongmin] Gannan Grassland Workstat Gansu Prov, Hezuo, Peoples R China. [Oosthuizen, Maria K. K.] Univ Pretoria, Mammal Res Inst, Hatfield, South Africa. [Wei, Wanrong; Zhang, Weiguo] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730200, Peoples R China. RP Wei, WR; Zhang, WG (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730200, Peoples R China. EM weiwr18@126.com; weizhang12332@163.com TC 0 Z9 0 DI 10.1002/ldr.4600 EA JAN 2023 UT WOS:000919701200001 DA 2023-03-23 ER PT J AU Zhang, YC Hong, SB Liu, D Piao, SL AF Zhang, Yichen Hong, Songbai Liu, Dan Piao, Shilong TI Susceptibility of vegetation low-growth to climate extremes on Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Both intensity and frequency of climate extreme events have significantly increased over the past decades, which triggered exceptional responses in terrestrial ecosystems. Resolving the responses of vegetation growth to climate extremes are essential but challenging. The Tibetan Plateau (TP), home to fragile alpine ecosystems, is sensitive to increased climatic variabilities and thus an ideal region to characterize various ecosystem response to climate extremes. In this study, we employed event coincidence analysis to detect the susceptibility (quantified by coincidence rate) of vegetation low-growth to four climate extremes (drought, extreme wet, extreme hot and cold) using Normalized Difference Vegetation Index (NDVI) and solar-induced chlorophyll fluorescence (SIF) over TP for the period 2001 to 2018. We found notable changes in the susceptibility of vegetation low-growth to climate extremes along climate gradients, with higher susceptibility to extreme hot generally being found in warmer regions, while higher susceptibility to extreme cold in colder regions. Meanwhile, susceptibility to drought decreased while that to extreme wet increased with increasing precipitation. We also found higher susceptibility of herbaceous plants for drought and extreme hot than woody plants, but their susceptibility to extreme wet and cold was relatively lower. The varied vegetation susceptibility to climate extremes along climate gradient and among different vegetation types were due to the sensitivity of vegetation to climate variability, rather than the intensity or frequency of climate extremes. This study identified the ecological sensitive regions under climate extreme events, and highlighted the risk of decline in vegetation growth under warm-droughts in spite of a wetting climate over Tibetan Plateau. C1 [Zhang, Yichen; Hong, Songbai; Piao, Shilong] Peking Univ, Sino French Inst Earth Syst Sci, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. [Liu, Dan; Piao, Shilong] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Piao, Shilong] Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. RP Hong, SB (通讯作者)，Peking Univ, Sino French Inst Earth Syst Sci, Coll Urban & Environm Sci, Beijing 100871, Peoples R China.; Liu, D (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. EM songbaih@pku.edu.cn; liu.dan@itpcas.ac.cn TC 0 Z9 0 PD MAR 15 PY 2023 VL 331 AR 109323 DI 10.1016/j.agrformet.2023.109323 EA JAN 2023 UT WOS:000922463900001 DA 2023-03-23 ER PT J AU Zhang, ZC Zhao, YR Lin, H Li, YP Fu, JM Wang, YX Sun, J Zhao, YH AF Zhang, Zhenchao Zhao, Yiran Lin, Hao Li, Yanpeng Fu, Jinmin Wang, Yingxin Sun, Juan Zhao, Yanhua TI Comprehensive analysis of grazing intensity impacts alpine grasslands across the Qinghai-Tibetan Plateau: A meta-analysis SO FRONTIERS IN PLANT SCIENCE DT Article AB Livestock grazing is a dominant practice in alpine grasslands and plays a crucial role in the ecosystem service of the Qinghai-Tibetan Plateau. The effects of grazing on alpine grasslands highly depends on grazing intensity. Up to now, we still lack comprehensive understanding of the general responses of alpine grasslands to different grazing intensities over broad geographic scales across the Qinghai-Tibetan Plateau. Here, we conducted a meta-analysis to explore the responses of plant characteristics and soil properties to grazing intensity in alpine grasslands of the Qinghai-Tibetan Plateau based on 52 peer-reviewed literatures. The results showed that grazing did not change the belowground biomass, while significantly increased the ratio of root to shoot (P< 0.05). Light grazing exhibited no significant effects on the plant richness, Shannon-Wiener diversity, soil water content, soil bulk density, nutrients, microbial biomass carbon, and microbial biomass nitrogen (P > 0.05). Moderate grazing significantly increased the plant richness and Shannon-Wiener diversity, while significantly decreased the soil organic carbon and total nitrogen (P< 0.05). Heavy grazing significantly decreased the plant richness, Shannon-Wiener diversity, water content, soil organic carbon, total nitrogen, microbial biomass carbon, and microbial biomass nitrogen, and significantly increased the soil bulk density (P< 0.05). These findings suggest that overgrazing is closely associated with grassland degradation, and moderate grazing is a sustainable practice to provide animal production and simultaneously maintain ecological functions for alpine grasslands on the Qinghai-Tibetan Plateau. C1 [Zhang, Zhenchao; Zhao, Yiran; Lin, Hao; Fu, Jinmin; Sun, Juan; Zhao, Yanhua] Qingdao Agr Univ, Coll Grassland Sci, Key Lab, Natl Forestry & Grassland Adm Grassland Resources, Qingdao, Shandong, Peoples R China. [Li, Yanpeng] Jiangxi Coll Appl Technol, Sch Mapping & Geog Informat, Ganzhou, Peoples R China. [Wang, Yingxin] Chinese Acad Forestry, Res Inst Ecol Conservat & Restorat, Grassland Res Ctr, Natl Forestry & Grassland Adm, Beijing, Peoples R China. RP Fu, JM; Zhao, YH (通讯作者)，Qingdao Agr Univ, Coll Grassland Sci, Key Lab, Natl Forestry & Grassland Adm Grassland Resources, Qingdao, Shandong, Peoples R China. EM turfcn@qq.com; zhaoyanhua@qau.edu.cn TC 0 Z9 0 PD JAN 17 PY 2023 VL 13 AR 1083709 DI 10.3389/fpls.2022.1083709 UT WOS:000919464400001 DA 2023-03-23 ER PT J AU Wang, J Zhang, CY Luo, P Yang, H Luo, C AF Wang, Jun Zhang, Chunyan Luo, Peng Yang, Hao Luo, Chuan TI Water yield response to plant community conversion caused by vegetation degradation and improvement in an alpine meadow on the northeastern Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Water provision is an important ecological function of alpine meadows on the Tibetan Plateau. Quantitative assess-ment of the effects of vegetation change induced by vegetation degradation and improvement on water yield (WY) in alpine meadows is urgent for rational water and grassland resources conservation and management. Previous stud-ies mainly focused on the effects of vegetation coverage. What is less clear is how the WY of alpine meadow changes under plant community conversion caused by vegetation degradation and improvement. To test the hypotheses that lysimeter drainage (LD) decreases in the vegetation-degraded meadow and recovers in the vegetation-improved meadow, and the LD decreases as the stress tolerance of dominant strategy decreases, in situ lysimeters with intact monoliths of well-vegetated alpine meadows subjected to vegetation intact (sedge-dominated), degraded (forb-domi-nated) and improved (fast-growing grass-dominated) were employed, and then plant communities among treatments were compared based on the quantitative competitor, stress tolerator, and ruderal (CSR) theory. Compared to the vegetation-intact monoliths, the LD of vegetation-degraded monoliths was 59 % lower owing to the deeper roots and greater aboveground growth. The LD of vegetation-improved monoliths was 83 % higher than that of vegetation-degraded monoliths due to the shallower roots but was 25 % lower than that of vegetation-intact monoliths due to the greater aboveground growth. The LD decreased along a plant community conversion gradient in which the S-selection of the dominance strategy decreased (R2 = 0.34, P = 0.022) and the C-selection increased (R2 = 0.71, P < 0.001), likely due to the significant covariation between community-weighted CSR strategy with eco-hydrological plant and soil properties. These results indicated that the community conversion caused by vegetation degradation reduces the WY of alpine meadows, and sowing fast-growing grasses can only partly restore this function. Application of stress-tolerant plants for vegetation improvement may be more efficient in recovering the WY of de-graded meadows, especially in flat meadows under humid climate. C1 [Wang, Jun] China West Normal Univ, Inst Environm Sci, Nanchong, Sichuan, Peoples R China. [Zhang, Chunyan] China West Normal Univ, Key Lab Southwest China Wildlife Resources Conserv, Minist Educ, Nanchong, Sichuan, Peoples R China. [Luo, Peng; Yang, Hao; Luo, Chuan] Chinese Acad Sci, Chengdu Inst Biol, Chengdu, Sichuan, Peoples R China. RP Wang, J (通讯作者)，China West Normal Univ, Inst Environm Sci, Nanchong, Sichuan, Peoples R China. EM wangjun@cwnu.edu.cn TC 1 Z9 1 PD JAN 15 PY 2023 VL 856 AR 159174 DI 10.1016/j.scitotenv.2022.159174 PN 2 UT WOS:000878989400011 DA 2023-03-23 ER PT J AU Tian, LH Yang, W Ji-Shi, A Ma, YH Zhao, WX Chen, YJ Zhou, QP Qu, GP Zhao, JX Wu, GL AF Tian, Lihua Yang, Wen Ji-Shi, Awei Ma, Yunhe Zhao, Wenxue Chen, Youjun Zhou, Qingping Qu, Guangpeng Zhao, Jingxue Wu, Gao-Lin TI Artificial reseeding improves multiple ecosystem functions in an alpine sandy meadow of the eastern Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article; Early Access AB Desertification in alpine grasslands is exacerbated by rapid climate change and intensive anthropogenic activity, which will substantially threaten the structure and function of alpine grassland ecosystems. Artificial reseeding was a widely used strategy for the restoration of alpine sandy grasslands. However, it is still unclear whether reseeding restoration can improve multiple ecosystem functions of sandy meadows. To narrow these knowledge gaps, we evaluated the changes in plant communities, soil conditions, and ecosystem multifunctionality (EMF) across native meadow, sandy meadow, and restored meadow on the eastern Tibetan Plateau, and further identified the links between individual and multiple ecosystem functions. Artificial reseeding had contributed to the promotion of plant diversity, productivity, soil fertility, and soil carbon and nitrogen sequestrations. However, the recovery levels of plant diversity, productivity, and soil fertility in the restored meadow were still far lower than that in the native meadow. The results revealed that the EMF index of the restored meadow increased greatly compared with the sandy meadow, but it did not recover to that of the native meadow level. In addition, short-term reseeding improved the aboveground EMF index more than the belowground EMF index. The EMF indexes and most individual ecosystem functions showed positive correlations with plant diversity and productivity. These findings indicated an important role of artificial reseeding in the restoration of ecosystem functions in the alpine sandy meadow, and it had critical implications for the regional ecological security and sustainable development of alpine grasslands. C1 [Tian, Lihua; Ji-Shi, Awei; Zhao, Wenxue; Chen, Youjun; Zhou, Qingping] Southwest Minzu Univ, Sichuan Zoige Alpine Wetland Ecosyst Natl Observat, Chengdu, Peoples R China. [Tian, Lihua; Ji-Shi, Awei; Zhao, Wenxue; Chen, Youjun; Zhou, Qingping] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu, Peoples R China. [Yang, Wen; Ma, Yunhe; Zhao, Jingxue] Lanzhou Univ, State Key Lab Herbage Improvement & Grassland Agro, Lanzhou, Peoples R China. [Yang, Wen; Ma, Yunhe; Zhao, Jingxue] Lanzhou Univ, Coll Ecol, Lanzhou, Peoples R China. [Zhao, Jingxue] Tibet Acad Agr & Anim Husb Sci, Grassland Sci Inst, State Key Lab Hulless Barley & Yak Germplasm Resou, Lhasa, Peoples R China. [Wu, Gao-Lin] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, Yangling, Peoples R China. [Zhao, Jingxue] Lanzhou Univ, Coll Ecol, State Key Lab Herbage Improvement & Grassland Agro, Lanzhou 730000, Peoples R China. [Zhao, Jingxue] Lanzhou Univ, Coll Ecol, Lanzhou 730000, Peoples R China. [Wu, Gao-Lin] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, Yangling 712100, Shaanxi, Peoples R China. RP Zhao, JX (通讯作者)，Lanzhou Univ, Coll Ecol, State Key Lab Herbage Improvement & Grassland Agro, Lanzhou 730000, Peoples R China.; Zhao, JX (通讯作者)，Lanzhou Univ, Coll Ecol, Lanzhou 730000, Peoples R China.; Wu, GL (通讯作者)，Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, Yangling 712100, Shaanxi, Peoples R China. EM zjx@lzu.edu.cn; wugaolin@nwsuaf.edu.cn TC 0 Z9 0 DI 10.1002/ldr.4588 EA JAN 2023 UT WOS:000915372700001 DA 2023-03-23 ER PT J AU Yandi, S Tao, M Huakun, Z Honglin, L Zhonghua, Z Li, M Ruimin, Q Hongye, S Tao, C Jingjing, W Xue, H AF Yandi, She Tao, Ma Huakun, Zhou Honglin, Li Zhonghua, Zhang Li, Ma Ruimin, Qin Hongye, Su Tao, Chang Jingjing, Wei Xue, Hu TI Characterization of the Plant-Soil feedback index in alpine meadow degradation and recovery: A field experiment SO FRONTIERS IN ENVIRONMENTAL SCIENCE DT Article AB Most plant-soil feedback studies have been conducted on the mechanism by which soil directly influences plant growth performance and mostly in indoor pot experiments; however, it is unclear how plant-soil feedback is influenced by plant, soil and microbial diversity in grassland ecosystems in alpine meadows with high plant diversity. In this study, plant-soil feedback patterns were investigated by analyzing plant, soil and microbial characteristics across seven gradients in the time series from light degradation to 10-years of recovery, classified into three categories: ecosystem multifunctionality, biotic and abiotic factors, and comparing the strength and magnitude of plant-soil feedback in alpine meadows of degradation stages and years of recovery. The results showed that the plant-soil feedback relationships in alpine meadows differed significantly in three aspects: ecosystem multifunctionality, biotic and abiotic factors in the degradation stage and recovery years, and under the degradation gradient, ecosystem multifunctionality decreased from 0.34 to -0.99 with the deepening of degradation, biotic factors increased from -0.17 to 0.09, and abiotic factors increased from -0.17 to 0.15, while in the recovery gradient, ecosystem multifunctionality showed a trend of increasing and then decreasing with increasing recovery years, while biotic and abiotic factors showed fluctuating changes. The plant-soil feedback index indicated that the strength and direction of plant-soil interactions during degradation and recovery were different, and the positive feedback effect was 0.34 and 0.38 in the early stage of degradation and recovery, respectively, which were greater than the negative feedback effect. With the deepening of degradation, the negative feedback effect became more and more obvious, and at the stage of extreme degradation, the negative feedback effect reached -0.99, which was much larger than the positive feedback effect. However, with the increase of the recovery years, the positive feedback effect gradually weakened, and finally all of them were negative feedback effects at 10-years of recovery. This study provides a scientific basis for understanding plant-soil feedback in alpine meadow ecosystems and indicates the direction for the next scientific recovery of alpine meadows. C1 [Yandi, She; Huakun, Zhou; Zhonghua, Zhang; Li, Ma; Ruimin, Qin; Hongye, Su; Tao, Chang; Jingjing, Wei; Xue, Hu] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining, Peoples R China. [Yandi, She; Tao, Ma] Qinghai Univ, Coll Agr & Anim Husb, Xining, Peoples R China. [Honglin, Li] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. Qinghai Normal Univ, Xining, Qinghai, Peoples R China. RP Huakun, Z (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining, Peoples R China. EM hkzhou@nwipb.cas.cn TC 0 Z9 0 PD JAN 10 PY 2023 VL 10 AR 1097030 DI 10.3389/fenvs.2022.1097030 UT WOS:000921840500001 DA 2023-03-23 ER PT J AU Fan, QS Ren, JF Ma, ZW Hou, FJ AF Fan, Qingshan Ren, Jingfei Ma, Zhouwen Hou, Fujiang TI Taste agents as modulators of the feeding behaviour of grazing yaks in alpine meadows SO ANIMAL DT Article AB Feeding behaviour plays a significant role in promoting good animal health and welfare. It is also reflec-tive of the quality and quantity of available feed. In fact, grazing livestock do not select their feed ran-domly, rather their behaviour is influenced by the texture, taste, and smell of each pasture species. Although taste agents are often used to modify feed intake for captive livestock, the effect on the feeding behaviour of grazing livestock has not yet been extensively evaluated in native grasslands. To address this gap in knowledge, herein, we sprayed three types of taste agents-salty (SA), sweet (SW), and bitter (BT)-on alpine meadows to investigate their effect on the grazing behaviour of yaks (Bos Grunniens) on the Qinghai-Tibetan Plateau (QTP). Behavioural observations showed that grazing was concentrated primarily in the morning and afternoon, while ruminating/resting peaked at noon; however, the diurnal behavioural patterns of grazing yaks were not affected by the taste agents. Application of the SA agent significantly increased the yaks' grazing time, bites per minute, bites per step, time per feeding station, and steps per feeding station, while significantly reducing walking time, steps per minute, and number of feeding stations per minute. Meanwhile, application of the SW agent significantly increased the yaks' time per feeding station, however, significantly reduced the steps per minute and number of feeding sta-tions per minute. In contrast, the BT agent significantly increased the yaks' walking time, steps per min-ute, and number of feeding stations per minute, while significantly reducing grazing time, bites per minute, bites per step, and time per feeding station. Application of the SA agent also significantly increased the intake of favoured, edible, and inedible forage, while the SW agent improved inedible for-age intake, however, had a more subtle effect on favoured and edible forage intake. Meanwhile, the BT agent had an inhibitory effect on grazing intake. Hence, the structural equation model suggested that taste agents may directly or indirectly influence grazing behaviour by regulating feeding behaviour. Our findings provide a theoretical basis for using taste agents in grasslands to control the grazing beha-viour of livestock and provide a method to promote the stability of grassland communities, while miti-gating the degradation of grasslands in the QTP.CO 2022 The Author(s). Published by Elsevier B.V. on behalf of The Animal Consortium. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). C1 [Fan, Qingshan; Ren, Jingfei; Ma, Zhouwen; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat,Minist Agr, Lanzhou 730020, Peoples R China. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat,Minist Agr, Lanzhou 730020, Peoples R China. EM cyhoufj@lzu.edu.cn TC 0 Z9 0 PD FEB PY 2023 VL 17 IS 2 AR 100703 DI 10.1016/j.animal.2022.100703 EA JAN 2023 UT WOS:000921548900001 DA 2023-03-23 ER PT J AU Shen, CM Liu, KB Tang, LY Peng, JL AF Shen, Caiming Liu, Kam-biu Tang, Lingyu Peng, Jinlan TI Holocene vegetational and climatic history of the Xuguo Co catchment in the central Tibetan Plateau SO FRONTIERS IN EARTH SCIENCE DT Article AB A 101-cm core was taken from a large lake in the central Tibetan Plateau. Its pollen and loss-on-ignition analyses provide a Holocene vegetational, climatic, and environmental history of the lake catchment. Pollen analysis shows that: dense steppe dominated regional vegetation in the early Holocene (9,200-8,000 cal. yr BP); regional vegetation coverage gradually decreased in the middle Holocene (8,000-4,100 cal. yr BP); and marsh meadow grew on the lake edge and sparse steppe occupied the lake catchment after 4,100 cal. yr BP. Our result also reveals that: 9,200-8,000 cal. yr BP witnessed summer temperature, monsoonal rainfall, and lake-level maxima, as well as few winter and spring aeolian activities and frequent wildfires; 8,000-4,100 cal. yr BP saw a nonlinear decline in temperature, rainfall, lake level, and wildfires; and modern climatic and environmental conditions were established after 4,100 cal. yr BP. Three major monsoon-weakening events at ca. 6,700, 5,800, and 4,100 cal. yr BP were detected by pollen signals and proxies of the climate and environment. C1 [Shen, Caiming] Yunnan Normal Univ, Fac Geog, Yunnan Key Lab Plateau Geog Proc & Environm Change, Kunming, Peoples R China. [Shen, Caiming; Liu, Kam-biu] Louisiana State Univ, Coll Coast & Environm, Dept Oceanog & Coastal Sci, Baton Rouge, LA 70803 USA. [Shen, Caiming; Tang, Lingyu; Peng, Jinlan] Chinese Acad Sci, Nanjing Inst Geol & Paleontol, Nanjing, Peoples R China. RP Shen, CM (通讯作者)，Yunnan Normal Univ, Fac Geog, Yunnan Key Lab Plateau Geog Proc & Environm Change, Kunming, Peoples R China.; Shen, CM (通讯作者)，Louisiana State Univ, Coll Coast & Environm, Dept Oceanog & Coastal Sci, Baton Rouge, LA 70803 USA.; Shen, CM (通讯作者)，Chinese Acad Sci, Nanjing Inst Geol & Paleontol, Nanjing, Peoples R China. EM cmshen@hotmail.com TC 0 Z9 0 PD JAN 5 PY 2023 VL 10 AR 1025552 DI 10.3389/feart.2022.1025552 UT WOS:000919318000001 DA 2023-03-23 ER PT J AU Ling, Y Yuan, S Xiong, YL Chen, SM Feng, JJ Zhao, JM Zhang, CL Lei, X You, MH Bai, SQ Ma, X AF Ling, Yao Yuan, Shuai Xiong, Yanli Chen, Shuming Feng, Junjie Zhao, Junming Zhang, Chenglin Lei, Xiong You, Minghong Bai, Shiqie Ma, Xiao TI Effect of Harvest Time on the Seed Yield and Quality of Kengyilia melanthera SO AGRONOMY-BASEL DT Article AB Kengyilia melanthera is one of the most important forages, and has received significant attention as a desirable ecological pioneer grass for conserving grasslands and mitigating degradation pressure in a region. It is widely distributed in the alpine sandy meadow zone of the Eastern Qinghai-Tibet Plateau (QTP). Therefore, determining the optimal harvest time of this species is critical. A two-year field experiment (2016-2017) was utilized in this study to evaluate the impact of eight harvest times on the seed yield and quality of K. melanthera 'Aba'. The results show that the fresh weight (FW), dry weight (DW), seed yield (SY), thousand-grain weight (TGW), accelerated aging germination percentage (AAGP), and dehydrogenase activity (DA) of seeds increased with the extension of harvest time in two trial years, while the water content (WC) of seeds decreased. In both trial years, the germination percentage (GEP), germination potential (GP), and acid phosphatase activity (APA) of seeds increased initially and then decreased with the extension of harvest time. The comprehensive evaluation of the membership function and hierarchical clustering revealed that the 30th day after peak anthesis was the optimal harvest time for both 2016 and 2017. During this time, FW, DW, SY, TGW, AAGP, DA, WC, GEP, GP, and APA reached their optimal value, with 0.815 g, 0.518 g, 1773.67 kg center dot hm(-2), 143.81%, 66%, 16.23 mu g center dot mL(-1), 36.01%, 87%, 85%, and 2.50 nmol center dot min(-1) in 2016 and 0.805 g, 0.515 g, 1847.42 kg center dot hm(-2), 133.96%, 65%, 16.52 mu g center dot mL(-1), 36.04%, 86.5%, 83.5%, and 2.55 nmol center dot min(-1) in 2017, respectively. This study uncovers several high-efficiency and long-term technological solutions for cultivating high yields and quality production of K. melanthera in East QTP. C1 [Ling, Yao; Yuan, Shuai; Xiong, Yanli; Chen, Shuming; Feng, Junjie; Zhao, Junming; Zhang, Chenglin; Ma, Xiao] Sichuan Agr Univ, Coll Grassland Sci & Technol, Chengdu 611130, Peoples R China. [Yuan, Shuai; Lei, Xiong; You, Minghong; Bai, Shiqie] Sichuan Acad Grassland Sci, Chengdu 611743, Peoples R China. RP Ma, X (通讯作者)，Sichuan Agr Univ, Coll Grassland Sci & Technol, Chengdu 611130, Peoples R China. EM maroar@126.com TC 0 Z9 0 PD JAN PY 2023 VL 13 IS 1 AR 55 DI 10.3390/agronomy13010055 UT WOS:000916637500001 DA 2023-03-23 ER PT J AU Mou, XM Shi, Y Yu, YW Degen, A AF Mou, Xiao Ming Shi, Ying Yu, Ying Wen Degen, Allan TI Age Structure and Self-Thinning of Four Poisonous Forbs in Alpine Meadows on the Qinghai-Tibetan Plateau SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB Age structure and self-thinning indicate the development of plant species and their adaptability to the environment, and the proportion of poisonous plants could reflect the status of grasslands degradation. Little is known about age structure and self-thinning of poisonous dicotyledonous forbs in the alpine meadows on the Tibetan Plateau. We selected four poisonous dicotyledonous species, namely Anaphalis lacteal, Stellera chamaejasme, Pedicularis kansuensis, and Gentiana straminea, and determined their age structures by using number of branches, crown diameters, and plant heights and their self-thinning by using dry weights and different components (branches, leaves, and inflorescences). The populations of the four species were pyramid shaped with a rich seedling and juvenile base, which demonstrated a strong ability to increase in number rapidly and adapt to the environment. The Godron index indicated that the stability of age structures of the four species were A. lacteal > S. chamaejasme > G. straminea > P. kansuensis. Significant self-thinning was exhibited by branches of A. lacteal, branches and leaves of S. chamaejasme, and inflorescences of P. kansuensis. The self-thinning exponents from the allometric relationships between biomass and density differed at the level of branches, leaves, and inflorescences in the four poisonous forbs. We concluded that the populations of the four poisonous species were stable and able to increase in number rapidly on the Qinghai-Tibetan Plateau. (c) 2022 The Society for Range Management. Published by Elsevier Inc. All rights reserved. C1 [Mou, Xiao Ming; Shi, Ying; Yu, Ying Wen] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Herbage Improvement & Grassland Agr, Lanzhou 730020, Peoples R China. [Degen, Allan] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, IL-84105 Beer Sheva, Israel. RP Yu, YW (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Herbage Improvement & Grassland Agr, Lanzhou 730020, Peoples R China. EM yuyw@lzu.edu.cn TC 0 Z9 0 PD JAN PY 2023 VL 86 BP 1 EP 8 DI 10.1016/j.rama.2022.10.003 UT WOS:000912490400001 DA 2023-03-23 ER PT J AU Peng, F Lai, CM Li, CY Ji, C Zhang, PF Sun, JB Chen, XJ You, QG Xue, X AF Peng, Fei Lai, Chimin Li, Chengyang Ji, Chen Zhang, Pengfei Sun, Jianbo Chen, Xiaojie You, Quangang Xue, Xian TI Plasticity in over-compensatory growth along an alpine meadow degradation gradient on the Qinghai-Tibetan Plateau SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Over-compensatory growth of plants after disturbance is generally preferred by grassland users and managers because of more forage. How the grassland productivity and the plant growth condition before disturbance affect the compensatory growth are important for grazing management and the understanding of grassland degradation, yet they are not well understood. A clipping experiment was conducted on the Qinghai-Tibetan Plateau to understand the compensatory growth and conditions for the occurrence of over-compensatory at alpine meadows with different degradation status. Results showed the competition for light constrains the plant growth post-clipping at non-degraded and slightly degraded alpine meadows, while the reduction of soil nitrogen limits it at heavily degraded alpine meadow. The biomass accumulated post-clipping was positively correlated with the growing season biomass in unclipped plots and the biomass at clipping in clipped plots. When the aboveground biomass at clipping was less than 40.10 g m(-2) and the growing season biomass was between 38 and 97 g m(-2), the over-compensatory growth of alpine meadow could occur. Higher clipping rate is required for the alpine meadow with high productivity but the maximum clipping rate should be less than 0.71 to induce the over-compensatory growth. Equal-compensatory occurred at non-degraded and slightly degraded, while over-compensatory growth was observed at moderately degraded and a marginally significant over-compensatory growth at heavily degraded alpine meadow. The over-compensatory growth occurred at moderately degraded alpine meadow is mainly due to the performance of forbs. Our results suggest that grazing at moderately degraded alpine meadow may induce the over-compensatory growth at the community level, but the over-compensatory growth of forbs at moderately degraded alpine meadow may aggravate the alpine meadow degradation. C1 [Peng, Fei; Lai, Chimin; Sun, Jianbo; Chen, Xiaojie; You, Quangang; Xue, Xian] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Beijing, Peoples R China. [Lai, Chimin; Sun, Jianbo; You, Quangang; Xue, Xian] Univ Chinese Acad Sci, Beijing, Peoples R China. [Li, Chengyang] Lingnan Normal Univ, Dept Geog, Zhanjiang, Peoples R China. [Ji, Chen] Chinese Acad Sci, Beiluhe Observat & Res Stn Frozen Soil Engn & Envi, Beijing, Peoples R China. [Zhang, Pengfei] Lanzhou Univ, Sch Life Sci, Lanzhou, Peoples R China. RP Peng, F (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Beijing, Peoples R China. EM pengfei@lzb.ac.cn TC 0 Z9 0 PD JAN 1 PY 2023 VL 325 AR 116499 DI 10.1016/j.jenvman.2022.116499 PN A UT WOS:000877488700003 DA 2023-03-23 ER PT J AU Wang, YB Liu, X Lv, MX Zhang, ZY AF Wang, Yibo Liu, Xin Lv, Mingxia Zhang, Zhongyang TI Mechanisms and influencing factors of hydrothermal processes in active layer soils on the Qinghai-Tibet Plateau under freeze-thaw action SO CATENA DT Article AB The Qinghai-Tibet Plateau (QTP) is a region with an extensive area of permafrost that is very sensitive to climate change. In this study, soil water and thermal dynamic processes in the active layer of the QTP permafrost area at the profile and slope scales were investigated. The results showed that the hydrothermal process in the active layer soil was strongly affected by freezing and thawing processes and external weather conditions. The tem-perature of the active layer fluctuated in tandem with air temperature. The soil water content was more stable during the freezing period and showed a "double-hump" trend during the thawing period. The correlation co-efficient between soil and air temperature decreased with depth, from 0.896 in the surface soil layer to 0.082 in the deep soil layer; and the correlation coefficient between unfrozen water content and soil temperature during the freezing period showed an overall increasing trend with depth. The soil layers at different depths at the top and bottom of slope profiles differed in their hydrothermal processes due to the physicochemical properties and texture of the soil and vegetation types. The water-heat exchange of the surface soil is more frequent than that of the deep soil, and the frequency is more at the bottom than at the top of the slope. The soil water content at a depth of 0.25 m was the highest in the profile in association with a higher organic matter content and the blocking effect of dense roots. The changes of soil hydrothermal process in the active layer accelerated the hydrological cycle and the spatial-temporal variability in water resources in the frozen soil area. These effects might lead to a series of ecological and environmental problems, such as permafrost degradation and deserti-fication in the QTP alpine meadow ecosystem. C1 [Wang, Yibo; Liu, Xin; Lv, Mingxia; Zhang, Zhongyang] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou, Peoples R China. RP Wang, YB (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou, Peoples R China. EM wangyib@lzu.edu.cn TC 0 Z9 0 PD JAN PY 2023 VL 220 AR 106694 DI 10.1016/j.catena.2022.106694 PN A UT WOS:000877826900002 DA 2023-03-23 ER PT J AU Ma, CH Xie, YW Duan, SB Qin, WH Guo, ZC Xi, GL Zhang, XY Bie, Q Duan, HM He, L AF Ma, Changhui Xie, Yaowen Duan, Si-Bo Qin, Wenhua Guo, Zecheng Xi, Guilin Zhang, Xueyuan Bie, Qiang Duan, Hanming He, Lei TI Characterization of spatio-temporal patterns of grassland utilization intensity in the Selinco watershed of the Qinghai-Tibetan Plateau from 2001 to 2019 based on multisource remote sensing and artificial intelligence algorithms SO GISCIENCE & REMOTE SENSING DT Article AB Due to the limitations of spatial quantification methods, the spatio-temporal patterns of grassland utilization intensity (GUI) in the Selinco watershed (SLCW), the core region of ecological security on the Qinghai-Tibetan Plateau, is unclear under multiple utilization modes. This paper quantified GUI by constructing the association between the potential and actual Enhanced Vegetation Index (EVI) of grasslands in terms of interannual variability. To obtain an accurate spatio-temporal dataset of potential EVI, the following two components were considered on. Firstly, the temporal lag effects of each raw climate factor were investigated to determine the optimal climate variables affecting vegetation productivity. Secondly, four machine learning (ML) algorithms, including an artificial neural network, random forest, support vector machine, and gradient boosting regression tree combined with the Bayesian model average, were used to construct grassland potential EVI models involving EVI, grassland type, and environmental factors (topography, soil, raw climate, and bioclimatic). Meanwhile, to maximize the performance of ML models, variable selection, variable transformation, and hyperparameter optimization were systematically implemented, where the hyperparameter optimization algorithms employ the grid search algorithm, Bayesian optimization, genetic algorithm, and particle swarm optimization. Then, the spatio-temporal dataset of GUI in the SLCW from 2001 to 2019 was established by using the above quantification method based on multisource remote sensing and artificial intelligence algorithms. The analysis of spatio-temporal variation in GUI showed that the implementation of ecological restoration projects leads to a significant and rapid decline in the overall GUI of the SLCW after 2010 (declining by 4.8%), which is more obvious in the non-nature reserve (declining by 9.3%). In the Qiangtang Nature Reserve within the SLCW, although the GUI shows a declining trend after 2010 because of the implementation of ecological restoration projects, it shows an insignificant increase from 2001 to 2019 due to the recovery increase of wildlife populations in recent decades. Besides, by exploring the effects of elevation and slope on the GUI, it is found that grasslands on higher slopes at lower elevations are at a greater risk of degradation due to more intensive grassland utilization. C1 [Ma, Changhui; Xie, Yaowen; Qin, Wenhua; Guo, Zecheng; Xi, Guilin; Zhang, Xueyuan; He, Lei] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Peoples R China. [Duan, Si-Bo] Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Key Lab Agr Remote Sensing, Minist Agr, Beijing 100081, Peoples R China. [Bie, Qiang] Lanzhou Jiaotong Univ, Fac Geomat, Lanzhou 730070, Peoples R China. [Duan, Hanming] Neijiang Normal Univ, Sch Geog & Resource Sci, Neijiang 641100, Peoples R China. [Xie, Yaowen] Lanzhou Univ, Coll Earth & Environm Sci, South Tianshui Rd, Lanzhou 730000, Peoples R China. RP Xie, YW (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, South Tianshui Rd, Lanzhou 730000, Peoples R China. EM xieyw@lzu.edu.cn TC 0 Z9 0 PD DEC 31 PY 2022 VL 59 IS 1 BP 2217 EP 2246 DI 10.1080/15481603.2022.2153447 UT WOS:000898306000001 DA 2023-03-23 ER PT J AU Li, CM Zhang, DR Xu, GC Yan, R Huang, Y Feng, LQ Yi, J Xue, XY Liu, HX AF Li, Chunming Zhang, Derong Xu, Gengchun Yan, Rui Huang, Yang Feng, Liuqing Yi, Jin Xue, Xiangyu Liu, Huixia TI Effects of Alpine Grassland Degradation on Soil Microbial Communities in Qilian Mountains of China SO JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION DT Article; Early Access AB Soil microbial community composition is sensitive to environmental changes and can be used as a predictor of grassland degradation. However, the response of microbial communities to alpine grassland degradation has not been well elucidated. Illumina MiSeq high-throughput sequencing technology was used to analyze the composition and diversity of soil microbial communities in three degraded grassland types, namely, non-degradation, moderate degradation, and severe degradation, in the alpine grasslands of Qilian Mountains. With the deterioration of alpine grasslands, soil pH increased significantly (P < 0.01). Soil water content (SWC), soil organic matter (SOC), total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), and available phosphorus (AP) showed a significant decreasing trend (P < 0.01). Soil microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), and microbial biomass phosphorus (MBP) significantly decreased (P < 0.01). Alpine grassland degradation significantly changed the community composition, and beta-diversity of soil bacteria and fungi changed significantly, but their alpha-diversity did not change significantly. Soil pH, SWC, AN, and MBN were the key factors limiting the changes in soil bacterial and fungal community composition. Alpine grassland degradation has changed soil microbial community composition, which should be the future focus of alpine grassland degradation restoration management. C1 [Li, Chunming; Zhang, Derong; Xu, Gengchun; Yan, Rui; Huang, Yang; Feng, Liuqing; Yi, Jin; Xue, Xiangyu; Liu, Huixia] Northwest Minzu Univ, Coll Life Sci & Engn, Lanzhou 730030, Peoples R China. RP Liu, HX (通讯作者)，Northwest Minzu Univ, Coll Life Sci & Engn, Lanzhou 730030, Peoples R China. EM liuhuixia2@aliyun.com TC 0 Z9 0 DI 10.1007/s42729-022-01092-4 EA DEC 2022 UT WOS:000905049000001 DA 2023-03-23 ER PT J AU Xi, GL Ma, CH Xie, YW Guo, ZC Bao, TA Zhang, XY Liu, YY Wang, HR AF Xi, Guilin Ma, Changhui Xie, Yaowen Guo, Zecheng Bao, Tana Zhang, Xueyuan Liu, Yiyang Wang, Haoran TI Spatialization method of monitoring grazing intensity: A case-study of the Tibet Selinco basin, Qinghai-Tibet Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article; Early Access AB The problem of grassland degradation induced by livestock production at the expense of local grasses has become a serious ecological problem worldwide. To maintain livestock production and sustainable grassland development, the extent and intensity of grassland utilization needs to be better understood. In this study, a model was developed to monitor the intensity of grazing in a typical grazing area (Tibet Selinco basin) of the Qinghai-Tibet Plateau. Combining the number of livestock at the township scale with their matching livestock habitat area and location, the biomass consumed by livestock was assigned to a productivity supply map (NPP) using a mathematical iterative algorithm from the perspective of different foraging habits of different livestock. The objective was to accurately measure the overall grazing pressure on the pasture as well as to estimate livestock pasture utilization. The model confirmed distinct spatial differences in the intensity of grassland utilization in the Tibet Selinco basin, in which the overall intensity was significantly low except in the southwestern region. The overall grazing area was found to be 150,000 km(2), of which moderate grazing area occupied 130,000 km(2) and overgrazing area occupied 20,000 km(2), accounting for 87% and 13% of the total grazing area, respectively. The proposed model can quantify human activities spatially and provide a reliable and accurate scientific basis for livestock production development and ecological environment management. C1 [Xi, Guilin; Ma, Changhui; Xie, Yaowen; Guo, Zecheng; Zhang, Xueyuan; Liu, Yiyang; Wang, Haoran] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou, Peoples R China. [Bao, Tana] Inner Mongolia Univ, Sch Ecol & Environm, Hohhot, Peoples R China. [Xie, Yaowen] Lanzhou Univ, Coll Earth & Environm Sci, 222 South Tianshui Rd, Lanzhou 730000, Peoples R China. RP Xie, YW (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, 222 South Tianshui Rd, Lanzhou 730000, Peoples R China. EM xieyw@lzu.edu.cn TC 0 Z9 0 DI 10.1002/ldr.4534 EA DEC 2022 UT WOS:000901512300001 DA 2023-03-23 ER PT J AU Ye, LF Liu, HY Deng, HD Zheng, YP Han, YW Gao, XT Abbott, LK Zhao, CM Li, JH AF Ye, Lu Feng Liu, Hong Yan Deng, Hao Dan Zheng, Yu Ping Han, Yong Wei Gao, Xin Ting Abbott, Lynette K. Zhao, Chang Ming Li, Jin Hua TI Effects of decadal nitrogen and phosphorus fertilization on microbial taxonomic and functional attributes associated with soil organic carbon decomposition and concentration in an alpine meadow SO ECOLOGICAL INDICATORS DT Article AB Microorganisms drive many important soil processes and ecosystem functioning; however, the soil microbial community can respond to environmental change, which can alter decomposition and storage of soil organic carbon (SOC). We assessed soil microbial taxonomic and functional attributes linked to SOC decomposition and concentration based on a grassland experiment fertilized with nitrogen (N) and phosphorus (P). There were divergent responses at both the taxonomic and functional level to fertilization, with a greater quantitative response in terms of the taxonomic attributes of bacteria and fungi than the abundance of SOC degradation genes. There was a negative correlation between SOC concentration and the abundance of SOC degradation genes. This indicated that N and P fertilization had the potential to stimulate SOC decomposition through modification of the soil microbial community, particularly by increasing the abundance of SOC degradation genes. Redundancy and variation partitioning analyses, as well as structural equation models revealed that soil total P was a pivotal factor shaping the microbial community both for taxonomic and functional gene attributes in the alpine meadow. The abundance of SOC degrading genes had stronger effects on SOC concentrations than did taxonomic attributes. Quantification of the abundance of SOC degradation genes can provide more direct and effective understanding of SOC decomposition processes and prediction of shifts in soil function as organic C pool in grasslands than a focus on the taxonomy of microbial communities. Given the important role of microbial community in regulating SOC decomposition and lower SOC concentrations under N and P fertilization, we recommend that the alpine meadow should be protected from mineral fertilizers, particularly P alone fertilization, to sustain high grassland ecosystem function as SOC sink in this region. C1 [Ye, Lu Feng; Liu, Hong Yan; Deng, Hao Dan; Zheng, Yu Ping; Zhao, Chang Ming; Li, Jin Hua] Lanzhou Univ, Coll Ecol, State Key Lab Herbage Improvement & Grassland Agro, Lanzhou 730000, Peoples R China. [Ye, Lu Feng; Deng, Hao Dan; Zheng, Yu Ping; Han, Yong Wei; Gao, Xin Ting] Chinese Res Inst Environm Sci, Beijing 100012, Peoples R China. [Abbott, Lynette K.] Univ Western Australia, UWA Sch Agr & Environm, Perth, WA 6000, Australia. [Abbott, Lynette K.] Univ Western Australia, UWA Inst Agr, Perth, WA 6000, Australia. [Zhao, Chang Ming; Li, Jin Hua] Gansu Prov Field Sci Observat & Res Stn Mt Ecosyst, Lanzhou 730000, Peoples R China. RP Li, JH (通讯作者)，Lanzhou Univ, Coll Ecol, State Key Lab Herbage Improvement & Grassland Agro, Lanzhou 730000, Peoples R China.; Abbott, LK (通讯作者)，Univ Western Australia, UWA Sch Agr & Environm, Perth, WA 6000, Australia.; Abbott, LK (通讯作者)，Univ Western Australia, UWA Inst Agr, Perth, WA 6000, Australia. EM lynette.abbott@uwa.edu.au; lijinhuap@sohu.com TC 0 Z9 0 PD FEB PY 2023 VL 146 AR 109790 DI 10.1016/j.ecolind.2022.109790 EA DEC 2022 UT WOS:000900174200002 DA 2023-03-23 ER PT J AU Liu, ZG Chen, Z Yu, GR Yang, M Zhang, WK Zhang, TY Han, L AF Liu, Zhaogang Chen, Zhi Yu, Guirui Yang, Meng Zhang, Weikang Zhang, Tianyou Han, Lang TI Ecosystem carbon use efficiency in ecologically vulnerable areas in China: Variation and influencing factors SO FRONTIERS IN PLANT SCIENCE DT Article AB Ecologically vulnerable areas (EVAs) are regions with ecosystems that are fragile and vulnerable to degradation under external disturbances, e.g., environmental changes and human activities. A comprehensive understanding of the climate change characteristics of EVAs in China is of great guiding significance for ecological protection and economic development. The ecosystem carbon use efficiency (CUEe) can be defined as the ratio of the net ecosystem productivity (NEP) to gross primary productivity (GPP), one of the most important ecological indicators of ecosystems, representing the capacity for carbon transfer from the atmosphere to a potential ecosystem carbon sink. Understanding the variation in the CUEe and its controlling factors is paramount for regional carbon budget evaluation. Although many CUEe studies have been performed, the spatial variation characteristics and influencing factors of the CUEe are still unclear, especially in EVAs in China. In this study, we synthesized 55 field measurements (3 forestland sites, 37 grassland sites, 6 cropland sites, 9 wetland sites) of the CUEe to examine its variation and influencing factors in EVAs in China. The results showed that the CUEe in EVAs in China ranged from -0.39 to 0.67 with a mean value of 0.20. There were no significant differences in the CUEe among different vegetation types, but there were significant differences in CUEe among the different EVAs (agro-pastoral ecotones < Tibetan Plateau < arid and semiarid areas < Loess Plateau). The CUEe first decreased and then increased with increasing mean annual temperature (MAT), soil pH and soil organic carbon (SOC) and decreased with increasing mean annual precipitation (MAP). The most important factors affecting the CUEe were biotic factors (NEP, GPP, and leaf area index (LAI)). Biotic factors directly affected the CUEe, while climate (MAT and MAP) and soil factors (soil pH and SOC) exerted indirect effects. The results illustrated the comprehensive effect of environmental factors and ecosystem attributes on CUEe variation, which is of great value for the evaluation of regional ecosystem functions. C1 [Liu, Zhaogang; Chen, Zhi; Yu, Guirui; Yang, Meng; Zhang, Weikang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China. [Liu, Zhaogang; Chen, Zhi; Yu, Guirui; Zhang, Weikang] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Chen, Zhi; Yu, Guirui] Univ Chinese Acad Sci, Yanshan Earth Crit Zone & Surface Fluxes Res Stn, Beijing, Peoples R China. [Zhang, Tianyou] Northwest A&F Univ, Coll Grassland Agr, Yangling, Peoples R China. [Han, Lang] Tianjin Univ, Inst Surface Earth Syst Sci, Sch Earth Syst Sci, Tianjin, Peoples R China. RP Chen, Z; Yu, GR (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China.; Chen, Z; Yu, GR (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China.; Chen, Z; Yu, GR (通讯作者)，Univ Chinese Acad Sci, Yanshan Earth Crit Zone & Surface Fluxes Res Stn, Beijing, Peoples R China. EM chenz@igsnrr.ac.cn; yugr@igsnrr.ac.cn TC 0 Z9 0 PD DEC 12 PY 2022 VL 13 AR 1062055 DI 10.3389/fpls.2022.1062055 UT WOS:000903681000001 DA 2023-03-23 ER PT J AU Ran, R Ni, ZX Hua, L Li, TR AF Ran, Rong Ni, Zhengxing Hua, Lei Li, Tingrou TI Does China's poverty alleviation policy improve the quality of the ecological environment in poverty-stricken areas? SO FRONTIERS IN ENVIRONMENTAL SCIENCE DT Article AB Poverty eradication and environmental protection as the two global goals of sustainable development. China's poverty alleviation policy attempts to achieve green development in poverty-stricken areas by eliminating poverty while also promoting environmental protection. Since the Poverty-stricken counties on the Qinghai-Tibet Plateau also have the dual attributes of ecological degradation and ecological fragility, it is of great significance to study the impact of poverty alleviation policy on their environment. In this research, taking poverty alleviation policy as the entry point, based on panel data and Remote Sensing Ecological Index for poverty-stricken counties on the Qinghai-Tibet Plateau from 2011 to 2019, and using the difference-in-differences (DID) method to verify the impact of policy on environmental quality. The main findings of the study were: 1) The poverty alleviation policy has a significant improvement effect on the ecological environment quality of counties in the Qinghai-Tibet Plateau region, and this conclusion still holds in a series of robustness tests using methods including the changing sample size method and the variable replacement method. Moreover, the policy effect has a certain time lag and its effect persists in the long term; 2) It is mainly due to the increased level of government public expenditure and the easing of government financial pressure that has contributed to the improvement of environmental quality in poverty-stricken areas; 3) Policy heterogeneity suggests that industrial poverty eradication policies are more conducive to promoting synergistic economic and environmental development in poverty-stricken areas. C1 [Ran, Rong; Ni, Zhengxing; Hua, Lei; Li, Tingrou] Chongqing Univ, Sch Publ Policy & Adm, Chongqing, Peoples R China. RP Hua, L (通讯作者)，Chongqing Univ, Sch Publ Policy & Adm, Chongqing, Peoples R China. EM Leihua@cqu.edu.cn TC 2 Z9 2 PD DEC 12 PY 2022 VL 10 AR 1067339 DI 10.3389/fenvs.2022.1067339 UT WOS:000902069000001 DA 2023-03-23 ER PT J AU Wang, K Xue, K Wang, ZS Liu, WJ Zhao, RC Wu, WC Tang, L Zhang, B Zhou, ST Hao, YB Cui, XY Jiang, LL Wang, SP Wang, YF AF Wang, Kui Xue, Kai Wang, Zongsong Liu, Wenjing Zhao, Runchen Wu, Wenchao Tang, Li Zhang, Biao Zhou, Shutong Hao, Yanbin Cui, Xiaoyong Jiang, Lili Wang, Shiping Wang, Yanfen TI Accelerated temporal turnover of the soil nematode community under alpine grassland degradation SO LAND DEGRADATION & DEVELOPMENT DT Article AB Soil nematodes play pivotal roles in the soil food web. However, the trophic regulation on nematodes in the soil micro-food web and its temporal dynamics are less explored. Here, we investigated the seasonal dynamics of soil nematode community in an alpine grassland on the Qinghai-Tibet Plateau at non-degraded (ND), moderately degraded (MD) and severely degraded (SD) stages, either under open-top chamber warming (W) or not (NW). Nematode richness was higher in SD than in MD and ND that did not differ, accompanied by a clear shift from the bottom-up regulation via belowground productivity in ND to the top-down regulation via omnivore and predator nematodes in SD. The intensified top-down regulation in SD was explained by increased proportions of predator and omnivore nematodes, likely induced by the expanded soil pore size in SD. As a result, accelerated temporal turnover of nematode community was observed under grassland degradation, which were 0.006 (slope, p = 0.78), 0.045 (p = 0.07), and 0.077 (p = 0.001) in ND, MD, and SD, respectively. Moreover, grassland degradation strengthened the association between nematode density and ecosystem respiration, whose slope was higher in SD (0.0025, p < 0.05) than in MD (0.0008, p < 0.01) or ND (insignificant). In contrast, warming did not affect the temporal turnover of the nematode community, richness, nor its role in ecosystem respiration. Overall, we revealed the accelerated temporal turnover of nematode community and its strengthened role in determining ecosystem respiration under alpine grassland degradation, suggesting that trophic cascade changes under ecosystem degradation may alter the ecosystem functioning. C1 [Wang, Kui; Wang, Zongsong; Wu, Wenchao; Hao, Yanbin] Univ Chinese Acad Sci, Coll Life Sci, Beijing, Peoples R China. [Xue, Kai; Liu, Wenjing; Zhao, Runchen; Tang, Li; Zhang, Biao; Zhou, Shutong; Wang, Yanfen] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Xue, Kai; Cui, Xiaoyong; Wang, Yanfen] Univ Chinese Acad Sci, Beijing Yanshan Earth Crit Zone Natl Res Stn, Beijing, Peoples R China. [Xue, Kai] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. [Xue, Kai] Weiqiao UCAS Sci & Technol Pk, Binzhou Inst Technol, Binzhou, Shandong, Peoples R China. [Jiang, Lili; Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing, Peoples R China. [Wang, Yanfen] State Key Lab Tibetan Plateau Earth Syst Sci LATPE, Beijing, Peoples R China. [Wang, Yanfen] Univ Chinese Acad Sci, 19 A Yuquan Rd, Beijing 100049, Peoples R China. RP Wang, YF (通讯作者)，Univ Chinese Acad Sci, 19 A Yuquan Rd, Beijing 100049, Peoples R China. EM yfwang@ucas.ac.cn TC 0 Z9 0 PD FEB 28 PY 2023 VL 34 IS 4 BP 1171 EP 1181 DI 10.1002/ldr.4524 EA DEC 2022 UT WOS:000897584300001 DA 2023-03-23 ER PT J AU Chen, DH Hou, HY Zhou, ST Zhang, S Liu, D Pang, Z Hu, JM Xue, K Du, JQ Cui, XY Wang, YF Che, RX AF Chen, Danhong Hou, Haiyan Zhou, Shutong Zhang, Song Liu, Dong Pang, Zhe Hu, Jinming Xue, Kai Du, Jianqing Cui, Xiaoyong Wang, Yanfen Che, Rongxiao TI Soil diazotrophic abundance, diversity, and community assembly mechanisms significantly differ between glacier riparian wetlands and their adjacent alpine meadows SO FRONTIERS IN MICROBIOLOGY DT Article AB Global warming can trigger dramatic glacier area shrinkage and change the flux of glacial runoff, leading to the expansion and subsequent retreat of riparian wetlands. This elicits the interconversion of riparian wetlands and their adjacent ecosystems (e.g., alpine meadows), probably significantly impacting ecosystem nitrogen input by changing soil diazotrophic communities. However, the soil diazotrophic community differences between glacial riparian wetlands and their adjacent ecosystems remain largely unexplored. Here, soils were collected from riparian wetlands and their adjacent alpine meadows at six locations from glacier foreland to lake mouth along a typical Tibetan glacial river in the Namtso watershed. The abundance and diversity of soil diazotrophs were determined by real-time PCR and amplicon sequencing based on nifH gene. The soil diazotrophic community assembly mechanisms were analyzed via iCAMP, a recently developed null model-based method. The results showed that compared with the riparian wetlands, the abundance and diversity of the diazotrophs in the alpine meadow soils significantly decreased. The soil diazotrophic community profiles also significantly differed between the riparian wetlands and alpine meadows. For example, compared with the alpine meadows, the relative abundance of chemoheterotrophic and sulfate-respiration diazotrophs was significantly higher in the riparian wetland soils. In contrast, the diazotrophs related to ureolysis, photoautotrophy, and denitrification were significantly enriched in the alpine meadow soils. The iCAMP analysis showed that the assembly of soil diazotrophic community was mainly controlled by drift and dispersal limitation. Compared with the riparian wetlands, the assembly of the alpine meadow soil diazotrophic community was more affected by dispersal limitation and homogeneous selection. These findings suggest that the conversion of riparian wetlands and alpine meadows can significantly alter soil diazotrophic community and probably the ecosystem nitrogen input mechanisms, highlighting the enormous effects of climate change on alpine ecosystems. C1 [Chen, Danhong; Zhang, Song; Hu, Jinming; Che, Rongxiao] Yunnan Univ, Inst Int Rivers & Ecosecur, Yunnan Key Lab Int Rivers & Transboundary Ecosecur, Kunming, Peoples R China. [Hou, Haiyan] Yunnan Univ, Sch Ecol & Environm Sci, Kunming, Peoples R China. [Zhou, Shutong; Pang, Zhe; Xue, Kai; Du, Jianqing; Cui, Xiaoyong; Wang, Yanfen] Univ Chinese Acad Sci, Coll Life Sci, Beijing, Peoples R China. [Zhang, Song] Nanjing Univ, Sch Environm, State Key Lab Pollut Control & Resource Reuse, Nanjing, Peoples R China. [Liu, Dong] Yunnan Univ, Sch Life Sci, Yunnan Key Lab Plateau Mt Ecol & Restorat Degraded, Kunming, Peoples R China. RP Che, RX (通讯作者)，Yunnan Univ, Inst Int Rivers & Ecosecur, Yunnan Key Lab Int Rivers & Transboundary Ecosecur, Kunming, Peoples R China. EM cherongxiao@ynu.edu.cn TC 0 Z9 0 PD DEC 8 PY 2022 VL 13 AR 1063027 DI 10.3389/fmicb.2022.1063027 UT WOS:000901623900001 DA 2023-03-23 ER PT J AU Guo, CR Wesche, K Margarint, MC Nowak, A Dembicz, I Wu, JS AF Guo, Chenrui Wesche, Karsten Margarint, Mihai Ciprian Nowak, Arkadiusz Dembicz, Iwona Wu, Jianshuang TI Climate overrides fencing and soil mineral nutrients to affect plant diversity and biomass of alpine grasslands across North Tibet SO FRONTIERS IN PLANT SCIENCE DT Article AB IntroductionOvergrazing and warming are thought to be responsible for the loss of species diversity, declined ecosystem productivity and soil nutrient availability of degraded grasslands on the Tibetan Plateau. Mineral elements in soils critically regulate plant individual's growth, performance, reproduction, and survival. However, it is still unclear whether plant species diversity and biomass production can be improved indirectly via the recovery of mineral element availability at topsoils of degraded grasslands, via grazing exclusion by fencing for years. MethodsTo answer this question, we measured plant species richness, Shannow-Wiener index, aboveground biomass, and mineral element contents of Ca, Cu, Fe, Mg, Mn, Zn, K and P at the top-layer (0 - 10 cm) soils at 15 pairs of fenced vs grazed matched sites from alpine meadows (n = 5), alpine steppes (n = 6), and desert-steppes (n = 4) across North Tibet. ResultsOur results showed that fencing only reduced the Shannon-Wiener index of alpine meadows, and did not alter aboveground biomass, species richness, and soil mineral contents within each grassland type, compared to adjacent open sites grazed by domestic livestock. Aboveground biomass first decreased and then increased along with the gradient of increasing Ca content but did not show any clear relationship with other mineral elements across the three different alpine grassland types. More than 45% of the variance in plant diversity indices and aboveground biomass across North Tibet can be explained by the sum precipitation during plant growing months. Structural equation modelling also confirmed that climatic variables could regulate biomass production directly and indirectly via soil mineral element (Ca) and plant diversity indices. DiscussionOverall, the community structure and biomass production of alpine grasslands across North Tibet was weakly affected by fencing, compared to the robst climatic control. Therefore, medium-term livestock exclusion by fencing might have limited contribution to the recovery of ecosystem structure and functions of degraded alpine grasslands. C1 [Guo, Chenrui; Wu, Jianshuang] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. [Guo, Chenrui] Hebei Univ Sci & Technol, Sch Environm Sci & Engn, Shijiazhuang, Peoples R China. [Wesche, Karsten] Senckenberg Museum Nat Hist Gorlitz, Dept Bot, Gorlitz, Germany. [Wesche, Karsten] Tech Univ Dresden, Int Inst IHI Zittau, Zittau, Germany. [Wesche, Karsten] German Ctr Integrat Biodivers Res iDiv, Leipzig, Germany. [Margarint, Mihai Ciprian; Wu, Jianshuang] Alexandru Ioan Cuza Univ, Geog & Geol Fac, Dept Geog, Iasi, Romania. [Nowak, Arkadiusz] Polish Acad Sci, Bot Garden Ctr Biol Divers Conservat Powsin, Warsaw, Poland. [Nowak, Arkadiusz] Univ Opole, Inst Biol, Opole, Poland. [Dembicz, Iwona] Univ Warsaw, Inst Environm Biol, Fac Biol, Dept Ecol & Environm Conservat, Warsaw, Poland. RP Wu, JS (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China.; Wu, JS (通讯作者)，Alexandru Ioan Cuza Univ, Geog & Geol Fac, Dept Geog, Iasi, Romania. EM wujianshuang@caas.cn TC 0 Z9 0 PD DEC 8 PY 2022 VL 13 AR 1024954 DI 10.3389/fpls.2022.1024954 UT WOS:000902013600001 DA 2023-03-23 ER PT J AU Zhang, ZC Zhan, TY Li, YP Wang, Y Yu, T Sun, J AF Zhang, Zhenchao Zhan, Tianyu Li, Yanpeng Wang, Yi Yu, Ting Sun, Juan TI Soil organic carbon stock responded more sensitively to degradation in alpine meadows than in alpine steppes on the Qinghai-Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Grassland degradation is commonly thought to cause soil organic carbon (SOC) change, and the response of SOC stock to degradation is highly dependent on grassland type. However, the effects of grassland type on changes in SOC stocks with grassland degradation over broad geographic scales remain unclear. Here, we explored the probably different responses of SOC stocks to grassland degradation for alpine meadows and alpine steppes based on 58 peer-reviewed publications regarding the Qinghai-Tibetan Plateau. The results showed that SOC stock consistently decreased with increasing degradation levels in both alpine meadows and steppes, whereas the magnitudes of reduction of SOC stock in alpine meadows were significantly larger than those in alpine steppes (p < 0.05). The variations in SOC stock were significantly positively correlated with variations in aboveground biomass in the alpine steppes only (p < 0.05) but were significantly positively correlated with variations in belowground biomass in both alpine meadows and alpine steppes (p < 0.01). The relationships between change rates of SOC stock with initial SOC stock and mean annual precipitation were both significantly negative during the lightly and moderately degraded stages, while the negative relationship became nonsignificant for the heavily degraded stage (p > 0.05). These findings suggest that soil organic carbon stock responded more sensitively to degradation in alpine meadows with higher initial SOC stock and annual mean precipitation than in alpine steppes. Our study might have significant implications for future sustainable management practices for carbon sequestration of alpine grasslands on the Qinghai-Tibetan Plateau. C1 [Zhang, Zhenchao; Zhan, Tianyu; Sun, Juan] Qingdao Agr Univ, Coll Grassland Sci, Key Lab, Natl Forestry Grassland Adm Grassland Resources &, Qingdao 266109, Shandong, Peoples R China. [Zhang, Zhenchao; Yu, Ting] Northwest A&F Univ, Inst Soil & Water Conservat, Key Lab Soil Eros & Dryland Farming Loess Plateau, Yangling, Peoples R China. [Zhan, Tianyu] Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing, Peoples R China. [Li, Yanpeng] China Univ Min & Technol, Sch Environm & Spatial Informat, Xuzhou, Peoples R China. [Li, Yanpeng] Jiangxi Coll Appl Technol, Sch Mapping & Geog Informat, Ganzhou, Peoples R China. [Wang, Yi] Sun Yat sen Univ, Sch Life Sci, Guangzhou, Peoples R China. RP Sun, J (通讯作者)，Qingdao Agr Univ, Coll Grassland Sci, Key Lab, Natl Forestry Grassland Adm Grassland Resources &, Qingdao 266109, Shandong, Peoples R China. EM sunjuan@qau.edu.cn TC 0 Z9 0 PD JAN 30 PY 2023 VL 34 IS 2 BP 353 EP 361 DI 10.1002/ldr.4463 EA DEC 2022 UT WOS:000914276800001 DA 2023-03-23 ER PT J AU Ma, L Zhang, ZH Shi, GX Su, HY Qin, RM Chang, T Wei, JJ Zhou, CY Hu, X Shao, XQ Sun, J Zhou, HK AF Ma, Li Zhang, Zhonghua Shi, Guoxi Su, Hongye Qin, Ruimin Chang, Tao Wei, Jingjing Zhou, Chenyu Hu, Xue Shao, Xinqing Sun, Jian Zhou, Huakun TI Warming changed the relationship between species diversity and primary productivity of alpine meadow on the Tibetan Plateau SO ECOLOGICAL INDICATORS DT Article AB Climate warming are supposed to have irreversible effects on the biodiversity and ecosystem functions of grassland. Alpine meadow is the predominant ecosystem in Qinghai-Tibet Plateau, which has attracted much attention because of its sensitivity to global changes. However, there is still no unified understanding of the impact of warming on the relationship between diversity and productivity of alpine meadows. In this study, we conducted multi-gradient warming, used fiberglass open-top chambers (OTCs) to raise the temperature, based on the investigation of community structure and productivity, we evaluated the effect of field simulated warming on the relationship of species diversity-primary productivity. Our result showed that gradient warming reduced species richness, diversity and dominance, inhibited the accumulation of above-ground biomass (AGB) and below-ground biomass (BGB), which was more significant under higher warming (P < 0.05). AGB had a significant linear positive correlation with Margalef index (R) and Shannon-Wiener index (H) (P < 0.05), but was weakly dependent on Simpson index (H') and Pielou index(E), while BGB was not affected by species diversity during the experiment. Our results revealed that simulated warming weakened the dependence of AGB on species diversity, and aggravated the negative correlation between BGB and species diversity (P < 0.05), which was mainly caused by the decrease of R, H, H' after warming. Functional group level, we found the AGB of Forbs increased significantly with the increase of species richness (P < 0.05), but warming had little effect on the relationship between them, while the relationship between species richness and AGB of Poaceae was significantly strengthened under warming. It concludes that the interaction between Poaceae and Forbs leads to a gradual decrease in above-ground biomass at the community level with the increase of species richness under warming. Our work provides an experimental data source for BEF research and verification under climate change scenarios, and an important reference for predicting and dealing with the impact of global climate change on adaptive management and grassland protection. C1 [Ma, Li; Zhang, Zhonghua; Su, Hongye; Qin, Ruimin; Chang, Tao; Hu, Xue; Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, 23 Xinning Rd, Xining 810008, Qinghai, Peoples R China. [Shi, Guoxi] Tianshui Normal Univ, Gansu Prov Key Lab Resource Utilizat Agr Solid Wa, Tianshui 741000, Peoples R China. [Wei, Jingjing; Zhou, Chenyu] Qinghai Normal Univ, Xining 810016, Peoples R China. [Shao, Xinqing] China Agr Univ, Beijing 100083, Peoples R China. [Sun, Jian] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. RP Zhou, HK (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, 23 Xinning Rd, Xining 810008, Qinghai, Peoples R China. EM hkzhou@nwipb.cas.cn TC 0 Z9 0 PD DEC PY 2022 VL 145 DI 10.1016/j.ecolind.2022.109691 UT WOS:000934000800008 DA 2023-03-23 ER PT J AU Meng, HM Yang, JR Sun, WJ Xiao, LJ Wang, GC AF Meng, Huimei Yang, Jingrui Sun, Wenjuan Xiao, Liujun Wang, Guocheng TI Aboveground Biomass in China's Managed Grasslands and Their Responses to Environmental and Management Variations SO AGRONOMY-BASEL DT Article AB Aboveground biomass (AGB) in managed grasslands can vary across a suite of environmental and management conditions; however, there lacks a quantitative assessment at the national scale of China. Although the potential effects of individual drivers (e.g., species, nutrient fertilization, and water management) have been examined in China's managed grasslands, no attempts have been made to comprehensively assess the effects of multiple variables on AGB. Using a meta-data analysis approach, we created a database composed of AGB and associated attributes of managed grasslands in China. The database was used to assess the responses of AGB to anthropogenic factors, in addition to a suite of natural variables including climate, soil, and topography. The average AGB in managed grasslands of China is approximately 630 g m(-2) of dry matter, ranging from 55 to 2172 g m(-2) (95% confidence interval). Medicago sativa is the most widely planted species in China's managed grasslands, followed by Elymus dahuricus and Bromus japonicus. The national average AGB of these three species was around 692, 530, and 856 g m(-2), respectively. For each species, AGB shows a large discrepancy across different places. In general, grassland AGB depends substantially on species, environments, and management practices. The dependence can be well described by a linear mixed-effects regression in which a series of biotic and abiotic factors are used as predictors. We highlight that establishing managed grassland can potentially contribute to not only AGB enhancement, but also grassland restoration on degraded natural grasslands. C1 [Meng, Huimei] Tibet Univ, Coll Sci, Lhasa 850000, Peoples R China. [Yang, Jingrui] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Peoples R China. [Yang, Jingrui] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Sun, Wenjuan] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Xiao, Liujun] Zhejiang Univ, Inst Agr Remote Sensing & Informat Technol, Coll Environm Resource Sci, Hangzhou 310058, Peoples R China. [Wang, Guocheng] Chinese Acad Sci, Inst Atmospher Phys, LAPC, Beijing 100029, Peoples R China. [Wang, Guocheng] Key Lab Agr Remote Sensing & Informat Syst, Hangzhou 310058, Peoples R China. RP Wang, GC (通讯作者)，Chinese Acad Sci, Inst Atmospher Phys, LAPC, Beijing 100029, Peoples R China.; Wang, GC (通讯作者)，Key Lab Agr Remote Sensing & Informat Syst, Hangzhou 310058, Peoples R China. EM wanggc@mail.iap.ac.cn TC 0 Z9 0 PD DEC PY 2022 VL 12 IS 12 AR 2913 DI 10.3390/agronomy12122913 UT WOS:000902058700001 DA 2023-03-23 ER PT J AU Wang, CW Liu, ZK Yu, WY Ye, XH Ma, LN Wang, RZ Huang, ZY Liu, GF AF Wang, Congwen Liu, Zhangkai Yu, Wanying Ye, Xuehua Ma, Linna Wang, Renzhong Huang, Zhenying Liu, Guofang TI Grassland Degradation Has Stronger Effects on Soil Fungal Community Than Bacterial Community across the Semi-Arid Region of Northern China SO PLANTS-BASEL DT Article AB Soil microbes play crucial roles in grassland ecosystem functions, such as soil carbon (C) pool and nutrient cycle. Soil microbes in grasslands are susceptible to the degradation mediated by climate change and anthropogenic disturbance. However, research on how the degradation influences the diversity and community structure of different soil microbial taxa is relatively scarce. We conducted a large-scale field survey to describe the effects of four degradation levels (PD: potential degradation, LD: light degradation, MD: moderate degradation, and SD: severe degradation) on soil bacterial and fungal community in the semi-arid grasslands of northern China. We found that soil moisture, nutrients, and clay content decreased, but soil sand content increased along the increasing degradation gradient. However, the degradation had no effects on soil pH and the C:N ratio. Grassland degradation had non-significant effect on soil bacterial diversity, but it significantly affected soil bacterial community structure. The degradation decreased soil fungal diversity and had a relatively larger influence on the community structure of soil fungi than that of bacteria. The community composition and structure of soil fungi were mainly affected by soil nutrients and texture, while those of soil bacteria were mainly affected by soil pH. These results indicate that changes in soil properties induced by grassland degradation mainly drive the variation in the soil fungal community and have less effect on the soil bacterial community. This study reveals the sensitivity of soil fungal community to grassland degradation, highlighting the priority of soil fungal community for the management and restoration of degraded grasslands. C1 [Wang, Congwen; Liu, Zhangkai; Yu, Wanying; Ye, Xuehua; Ma, Linna; Wang, Renzhong; Huang, Zhenying; Liu, Guofang] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Wang, Congwen; Liu, Zhangkai; Wang, Renzhong] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Yu, Wanying] Northeast Normal Univ, Inst Grassland Sci, Key Lab Vegetat Ecol, Minist Educ, Changchun 130024, Peoples R China. RP Huang, ZY; Liu, GF (通讯作者)，Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. EM zhenying@ibcas.ac.cn; liugf@ibcas.ac.cn TC 0 Z9 0 PD DEC PY 2022 VL 11 IS 24 AR 3488 DI 10.3390/plants11243488 UT WOS:000903035400001 DA 2023-03-23 ER PT J AU Yang, JH Wu, GL Jiao, JY Dyck, M He, HL AF Yang, Jiahui Wu, Gaolin Jiao, Juying Dyck, Miles He, Hailong TI Freeze-thaw induced landslides on grasslands in cold regions SO CATENA DT Article AB Landslides induced by freeze-thaw processes on grasslands are one of the major geohazards, and their scale and frequency are increasing as the global warms. Freeze-thaw induced landslides degrade surface vegetation and soil properties, reduce biodiversity, intensify landscape fragmentation, and lead to losses in economy, human and animal lives. Despite substantial progress in research on landslides, there has been little study focused on how ground freeze-thaw events affect landslides. By critically analyzing previous studies, this paper proposes a conceptual framework for the forms and types, development, dominant factors, monitoring techniques, and impact mechanisms of freeze-thaw induced landslides. Landslides are controlled by soil characteristics and topographic slope, which are major intrinsic determinants. Increased rainfall, rising temperatures, and thickening active layer due to climate change are all direct drivers of freeze-thaw induced landslides. Vegetation conditions, animal behavior interference, and wind erosion all affect the occurrence and development process of landslides by modifying vegetation cover, soil physical and chemical properties, and structure. Currently, landslide monitoring techniques have evolved rapidly with improved efficiency and accuracy, but with only few applications for freeze-thaw induced landslides. There are a variety of prediction models for landslides, but few consider freeze-thaw effects and lack field validation. The new perspective on the occurring types and dominant factors enhances theoretical understanding of the formation mechanisms, which helps further monitor and analysis of freeze-thaw induced landslides. Future studies should concentrate on the coupling mechanism of multiple factors and the development of an accurate prediction system, which will greatly benefit the understanding and early detection of freeze-thaw induced landslides. C1 [Yang, Jiahui; Wu, Gaolin; He, Hailong] Northwest A&F Univ, Coll Nat Resources & Environm, Yangling 712100, Shaanxi, Peoples R China. [Yang, Jiahui; He, Hailong] Northwest A&F Univ, Key Lab Plant Nutr & Agrienvironm Northwest China, Minist Agr, Yangling 712100, Shaanxi, Peoples R China. [Wu, Gaolin; Jiao, Juying; He, Hailong] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, Yangling 712100, Shaanxi, Peoples R China. [Dyck, Miles] Univ Alberta, Dept Renewable Resources, Edmonton, AB T6G 2H1, Canada. RP He, HL (通讯作者)，Northwest A&F Univ, Coll Nat Resources & Environm, Yangling 712100, Shaanxi, Peoples R China. EM jiahui.yang@nwafu.edu.cn; wugaolin@nwsuaf.edu.cn; jyjiao@ms.iswc.ac.cn; miles.dyck@ualberta.ca; hailong.he@hotmail.com TC 2 Z9 2 PD DEC PY 2022 VL 219 AR 106650 DI 10.1016/j.catena.2022.106650 UT WOS:000864646700004 DA 2023-03-23 ER PT J AU Yao, XX Li, CH Ahmad, AA Tariq, A Degen, AA Bai, YF AF Yao, Xixi Li, Changhui Ahmad, Anum Ali Tariq, Akash Degen, A. Allan Bai, Yanfu TI An increase in livestock density increases forage nutritional value but decreases net primary production and annual forage nutritional yield in the alpine grassland of the Qinghai-Tibetan Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB Pasture biomass and quality are dependent on herbivore grazing and precipitation, but the responses of vegetation to the interactive effects of climate and grazing regimes remain unclear. We conducted an eight-year sheep grazing experiment with 4 stocking rates (0, 3.5, 5.5, and 7.5 sheep/ha) in an alpine meadow of the northeastern Tibetan Plateau. The above-ground net primary productivity (ANPP) and forage nutritional value (FNV) of four dominant species (Poa annua, Kobresia humilis, Astragalus adsurgens and Potentilla fruticosa) were measured during a wet year (360 mm rainfall) and a drought year (216 mm rainfall). The FNV was used as indicator of forage quality and was calculated from the crude protein (CP) content, in vitro true dry matter digestibility (IVTD), metabolic energy (ME) yield, and neutral detergent fiber (NDF) content of the plant. The stocking rate explained a minimum of 76% of the variations of ANPP, and the precipitation sub-additive effect for ANPP ranged from 5% to 12%. The interaction of sheep stocking rate and precipitation affected ANPP of the 4 species, except for P. fruticosa. The FNV of the pasture increased with increasing grazing pressure, but ANPP and forage nutritional yield (FNY) decreased. In calculating FNY, the increase in FNV did not compensate for the decrease in ANPP. In non-grazed plots, the CP yield declined sharply (18%-55%) in response to drought, but there was no effect on ME yield. The interaction between stocking rate and precipitation affected forage quality of the 4 plant species differently. The grassland ANPP and FNY could be maintained at a grazing intensity of 3.5 sheep/ha in wet and dry years. Our results highlight that stocking density affects pasture ANPP and FNV, and is contingent on rainfall. C1 [Yao, Xixi; Li, Changhui] Qinghai Univ, Coll Agr & Anim Husb, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Ahmad, Anum Ali] Chinese Acad Agr Sci, Lanzhou Inst Husb & Pharmaceut Sci, Lanzhou, Peoples R China. [Tariq, Akash] Chinese Acad Sci, Xinjiang Inst Ecol & Geog, Xinjiang Key Lab Desert Plant Roots Ecol & Vegetat, Urumqi, Peoples R China. [Degen, A. Allan] Beng Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, Beer Sheva, Israel. [Bai, Yanfu] Sichuan Agr Univ, Coll Grassland Sci & Technol, Chengdu, Peoples R China. RP Li, CH (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China.; Bai, YF (通讯作者)，Sichuan Agr Univ, Coll Grassland Sci & Technol, Chengdu, Peoples R China. EM 746886595@qq.com; baiyf@sicau.edu.cn TC 0 Z9 0 PD NOV 24 PY 2022 VL 13 AR 1020033 DI 10.3389/fpls.2022.1020033 UT WOS:000894112800001 DA 2023-03-23 ER PT J AU Hu, Y Gou, XW Tsunekawa, A Cheng, YX Hou, FJ AF Hu, Yi Gou, Xiaowei Tsunekawa, Atsushi Cheng, Yunxiang Hou, Fujiang TI Assessment of the vegetation sensitivity index in alpine meadows with a high coverage and toxic weed invasion under grazing disturbance SO FRONTIERS IN PLANT SCIENCE DT Article AB Maintaining healthy ecosystems is essential to ensure sustainable socio-economic development. Studies combining remote sensing data with grassland health assessments, extensively performed at different scales, are important for monitoring grassland health from a spatiotemporal perspective to enable scientific grazing management. However, most studies only use quantitative grassland degradation indices, such as grassland cover; this is done despite the fact that some degraded grasslands maintain a high level of cover solely by virtue of the proliferation of toxic weeds. Thus, seeking indices that are a more accurate representation of the health status of grassland vegetation is of utmost importance. Therefore, in order to accurately characterize the ecological integrity of grasslands (i.e., while limiting the impact of confounding variables such as weeds), we chose the grassland health comprehensive evaluation index VOR (vigor, organization, and resilience) to assess the health of grasslands on the Tibetan Plateau. We applied the VOR evaluation indices to two rangelands with different grazing intensity on the Tibetan Plateau, and extracted 11 commonly used vegetation indices based on remote sensing images of rangelands,then modeled them with the data from field surveys. Our results show that the FVC, PS, and VOR were higher in lightly grazed pastures than in heavily grazed pastures in the 2017 and 2018 growing seasons. At the beginning of the sampling period, Poaceae accounted for a greater proportion in the HG pasture. However, by August 2018, the proportion of Poaceae in the LG pasture exceeded that in the HG pasture. the proportion of Forbs in the HG pasture was significantly greater than that in the LG pasture. This indicates that vegetation response to grazing disturbance is not only a volume reduction but also a vegetation composition change. The ratio vegetation index was the most sensitive to the vegetation health response, enabling the quantification and prediction of regional vegetation health and objectively reflecting the actual condition of the grassland ecosystem. According to a multiple regression analysis, the main climatic limiting factor in the region is precipitation, which positively correlated with VOR; whereas, grazing disturbance is an important driving factor, and it is inversely correlated with VOR. C1 [Hu, Yi; Tsunekawa, Atsushi; Cheng, Yunxiang] Inner Mongolia Univ, Sch Ecol & Environm, Hohhot, Peoples R China. [Hu, Yi; Tsunekawa, Atsushi; Cheng, Yunxiang] Minist Educ China, Key Lab Ecol & Resource Use Mongolian Plateau, Hohhot, Peoples R China. [Gou, Xiaowei; Tsunekawa, Atsushi] China Agr Univ, Coll Grassland Sci & Technol, Dept Grassland Resource & Ecol, Beijing, Peoples R China. [Tsunekawa, Atsushi] Tottori Univ, Arid Land Res Ctr, Hamasaka, Tottori, Japan. [Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou, Peoples R China. RP Cheng, YX (通讯作者)，Inner Mongolia Univ, Sch Ecol & Environm, Hohhot, Peoples R China.; Cheng, YX (通讯作者)，Minist Educ China, Key Lab Ecol & Resource Use Mongolian Plateau, Hohhot, Peoples R China. EM chengyx@imu.edu.cn TC 0 Z9 0 PD NOV 23 PY 2022 VL 13 AR 1068941 DI 10.3389/fpls.2022.1068941 UT WOS:000893815500001 DA 2023-03-23 ER PT J AU Lai, CM Peng, F Sun, JB Zhou, J Li, CY Xu, XL Chen, XJ You, QG Sun, HY Sun, J Xue, X Lambers, H AF Lai, Chimin Peng, Fei Sun, Jianbo Zhou, Jun Li, Chengyang Xu, Xingliang Chen, Xiaojie You, Quangang Sun, Hongyang Sun, Jian Xue, Xian Lambers, Hans TI Niche differentiation and higher uptake of available nitrogen maintained the productivity of alpine meadow at early degradation SO BIOLOGY AND FERTILITY OF SOILS DT Article AB A short-term in situ (15) N labeling experiment was conducted to investigate whether the N uptake and preference for different forms of available soil N for dominant plant species and soil microorganisms relate to the plant community productivity change at the no degradation stage, early stage of degradation, and late stage of degradation in an alpine meadow on the Qinghai-Tibetan Plateau. At the early stage of degradation in the alpine meadow, aboveground net primary productivity decreased, while belowground net primary productivity increased. As a result, the total net primary productivity was unchanged at the early stage of degradation. Both aboveground and belowground net primary productivity significantly decreased at the late stage of degradation compared with the non-degraded meadows. Plants and microorganisms mainly absorbed inorganic N and preferred NH4+ at the non-degraded meadows where available soil N (the total concentration of exchangeable NH4+, NO3-, and dissolved organic N) was maintained at a high level of 60.9 mu g N g(-1) dry soil, indicating an N-use chemical niche overlap. Plants and microorganisms showed a niche differentiation at the early stage of degradation where available soil N decreased to a medium level of 44.6 mu g N g(-1) dry soil; plants preferred NO3-, while microorganisms took up more NH4+. In contrast, microorganisms increased their uptake of organic N, while plants assimilated more inorganic N, indicating that plants and microorganisms showed a niche differentiation where available soil N decreased to a low level of 26.6 mu g N g(-1) dry soil at the late stage of degradation. The higher N uptake (30% increase of N uptake compared with non-degraded meadows) of dominant plant species and niche differentiation in using available soil N between plants and microorganisms are two mechanisms maintaining the total community net primary productivity, even when available soil N decreased at the early stage of degradation. Plants and microorganisms also showed a niche differentiation when available N declined further at the late stage of degradation. However, the N uptake by dominant plant species greatly declined at the late stage of degradation (76% reduction of N uptake compared with non-degraded meadows), which might explain the community net primary productivity reduction (78% lower compared with non-degraded meadows). C1 [Lai, Chimin; Peng, Fei; Sun, Jianbo; Chen, Xiaojie; You, Quangang; Xue, Xian] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou, Peoples R China. [Lai, Chimin; Sun, Jianbo; Chen, Xiaojie] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Peng, Fei] Chinese Acad Sci, Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Lanzhou, Peoples R China. [Zhou, Jun; Sun, Hongyang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu, Peoples R China. [Li, Chengyang] Lingnan Normal Univ, Dept Geog, Zhanjiang, Peoples R China. [Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China. [Sun, Jian] Chinese Acad Sci, Inst Tibetan Plateau Res, Stake Key Lab Earth Syst Resources & Environm Tib, Beijing, Peoples R China. [Lambers, Hans] Univ Western Australia, Sch Biol Sci, Perth, WA, Australia. [Lambers, Hans] Univ Western Australia, Inst Agr, Perth, WA, Australia. RP Peng, F; Xue, X (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou, Peoples R China.; Peng, F (通讯作者)，Chinese Acad Sci, Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Lanzhou, Peoples R China. EM pengfei@lzb.ac.cn; xianxue@lzb.ac.cn TC 0 Z9 0 PD JAN PY 2023 VL 59 IS 1 BP 35 EP 49 DI 10.1007/s00374-022-01679-0 EA NOV 2022 UT WOS:000880512200001 DA 2023-03-23 ER PT J AU Yang, YT Sun, Y Niu, B Feng, YF Han, FS Li, M AF Yang, Yuting Sun, Yi Niu, Ben Feng, Yunfei Han, Fusong Li, Meng TI Increasing connections among temporal invariability, resistance and resilience of alpine grasslands on the Tibetan Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB Ecological stability contains multiple components, such as temporal invariability, resistance and resilience. Understanding the response of stability components to perturbations is beneficial for optimizing the management of biodiversity and ecosystem functioning. Although previous studies have investigated the effects of multiple perturbations on each stability component, few studies simultaneously measure the multiple stability components and their relationships. Alpine grasslands on the Tibetan Plateau are exposed to co-occurring perturbations, including climate change and human activities. Here, we quantified three stability components (temporal invariability, resistance, and resilience) of alpine grasslands on the Tibetan Plateau during periods of high (2000-2008) and low (2009-2017) human activity intensity, respectively. We focused on the effects of climate variables (temperature, precipitation, radiation) and human activities (grazing intensity) on covariation among stability components. The results show that (1) for periods of high and low human activity, temporal invariability was positively correlated with resistance and resilience, while resistance was independent of resilience; (2) the dimensionality of alpine grasslands decreased by almost 10%, from 0.61 in the first period to 0.55 in the second period, suggesting the increasing connections among temporal invariability, resistance and resilience of alpine grasslands; and (3) temperature but not grazing intensity dominated the changes in the dimensionality of stability. These findings improve our understanding of multi-dimensional stability and highlight the importance of climate variability on alpine grassland stability on the Tibetan Plateau. C1 [Yang, Yuting; Sun, Yi; Li, Meng] Nantong Univ, Sch Geog Sci, Nantong, Peoples R China. [Niu, Ben; Han, Fusong] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, Beijing, Peoples R China. [Feng, Yunfei] Tangshan Normal Univ, Dept Resource Management, Tangshan, Peoples R China. RP Li, M (通讯作者)，Nantong Univ, Sch Geog Sci, Nantong, Peoples R China.; Han, FS (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, Beijing, Peoples R China. EM hanfs.17b@igsnrr.ac.cn; limeng@ntu.edu.cn TC 0 Z9 0 PD NOV 9 PY 2022 VL 13 AR 1026731 DI 10.3389/fpls.2022.1026731 UT WOS:000887353900001 DA 2023-03-23 ER PT J AU Cuo, L Zhang, YX Li, N AF Cuo, Lan Zhang, Yongxin Li, Ning TI Historical and Future Vegetation Changes in the Degraded Frozen Soil and the Entire Tibetan Plateau and Climate Drivers SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES DT Article AB About 99% of the Tibetan Plateau (TP) is covered by frozen soils and degradation of frozen soils will certainly impact TP's ecosystems. Here, we investigate decadal changes of frozen soils and net primary productivity (NPP, representing vegetation) in the degraded frozen soil zones and the TP during 1982-2014 and 2015-2100 using a dynamic vegetation model, historical records and the latest CMIP6 projections, as well as observation-based soil temperature thresholds. In 1982-2014, degraded permafrost soil zones were in the range of 316,975-455,402 km(2), with mean annual NPP staying around 84.9 gCm(-2) and annual NPP showing a significant reduction at -1.71 gCm(-2)/year due primarily to warming air. Seasonally frozen soil also degraded by 15,636 km(2) in the southeast TP, with mean annual NPP staying around 620.0 gCm(-2) and annual NPP showing a significant increase at 11.00 gCm(-2)/year. In the future, frozen soil continues to degrade and the degradation accelerates toward the end of the century such that only 2.7% of permafrost soil in 2014 is left by 2080-2100 under the shared socioeconomic pathway SSP5-8.5. Mean annual NPP in the permafrost soil degraded zones in 2015-2100 is about half of that for 1982-2014, with spatially mixed decrease and increase trends in the near-, mid-, and long-term periods. Over the seasonally frozen soil degraded zones and the entire TP, more positive than negative annual NPP changes are seen in 2015-2100, especially in the southeast of the TP, due to improved growing conditions and the expansion of primarily subtropical and temperate scrubland. C1 [Cuo, Lan; Li, Ning] Chinese Acad Sci, Key Lab Tibetan Environm Changes & Land Surface P, Inst Tibetan Plateau Res, Beijing, Peoples R China. [Cuo, Lan] Univ Chinese Acad Sci, Beijing, Peoples R China. [Cuo, Lan; Li, Ning] Chinese Acad Sci, State Key Lab Tibetan Plateau Earth Syst & Resour, Inst Tibetan Plateau Res, Beijing, Peoples R China. [Zhang, Yongxin] Natl Ctr Atmospher Res, Res Applicat Lab, Boulder, CO USA. RP Cuo, L (通讯作者)，Chinese Acad Sci, Key Lab Tibetan Environm Changes & Land Surface P, Inst Tibetan Plateau Res, Beijing, Peoples R China.; Cuo, L (通讯作者)，Univ Chinese Acad Sci, Beijing, Peoples R China.; Cuo, L (通讯作者)，Chinese Acad Sci, State Key Lab Tibetan Plateau Earth Syst & Resour, Inst Tibetan Plateau Res, Beijing, Peoples R China. EM lancuo@itpcas.ac.cn TC 1 Z9 1 PD NOV PY 2022 VL 127 IS 11 AR e2022JG006987 DI 10.1029/2022JG006987 UT WOS:000888176300001 DA 2023-03-23 ER PT J AU Guo, HN Wang, SY He, XB Ding, YJ Fan, YW Fu, H Hong, XF AF Guo, Haonan Wang, Shaoyong He, Xiaobo Ding, Yongjian Fan, Yawei Fu, Hui Hong, Xiaofeng TI Characteristics of Evapotranspiration and Crop Coefficient Correction at a Permafrost Swamp Meadow in Dongkemadi Watershed, the Source of Yangtze River in Interior Qinghai-Tibet Plateau SO WATER DT Article AB The Qinghai-Tibet Plateau (QTP), known as the Earth's third pole, is highly sensitive to climate change. Various environmental degradation has occurred due to the effects of climate warming such as the degradation of permafrost and the thickening of active layers. Evapotranspiration, as a key element of hydrothermal coupling, has become a key factor of the plateau environment for deciphering deterioration, and the FAO P-M model has a good physical foundation and simple model data requirements as a primary tool to study the plateau evapotranspiration. There has been a large research base, but the estimation of evapotranspiration in alpine regions is still subject to many uncertainties. This is reflected in the fact that the classification of underlying surface types has not been sufficiently detailed and the evapotranspiration characteristics of some special underlying surface types are still unclear. Therefore, in this work, we modified the FAO P-M coefficients based on the characteristics of actual evapotranspiration measured by the Eddy covariance system and the key influencing factors to better simulate the actual evapotranspiration in alpine swamp meadow. The results were as follows: (1) Both ETa measured by the Eddy covariance system and ET0 calculated by FAO P-M showed the same trend at the daily and annual scales and hysteresis was confirmed to exist, so the error caused by hysteresis should be considered in further research. (2) The annual ETa was 566.97 mm and annual ETa/P was 0.76, and about 11.19% of ETa occurred during the night. The ETa was 2.15 during the non-growing seasons, implying that a large amount of soil water was released into the air by evapotranspiration. (3) The evapotranspiration characteristics of alpine swamp meadow are formed under the following conditions: control of net radiation (R-n) affected by VPD during the growing season and affected by soil temperature and humidity during the non-growing season. Precipitation and soil water content are no longer the main controlling factors of evapotranspiration during the growing season at the alpine swamp meadow as the volume soil water content tends to saturate. (4) The basic corrected K-c was 1.14 during the initial and mid-growing season, 1.05 during the subsequent growing season, and 0-0.25 during the non-growing season, and the correction factor process can also provide ideas for correcting the K-c of other vegetation. C1 [Guo, Haonan; Wang, Shaoyong; He, Xiaobo; Ding, Yongjian] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China. [Guo, Haonan; Wang, Shaoyong; Fan, Yawei] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Fan, Yawei] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. [Fu, Hui] China Inst Water Resources & Hydropower Res, Beijing 100049, Peoples R China. [Hong, Xiaofeng] Yangtze River Sci Res Inst, Water Resources Dept, Wuhan 430010, Peoples R China. RP He, XB (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China. EM hxb@lzb.ac.cn TC 0 Z9 0 PD NOV PY 2022 VL 14 IS 21 AR 3578 DI 10.3390/w14213578 UT WOS:000883978300001 DA 2023-03-23 ER PT J AU Ma, ZW Qin, WP Wang, ZQ Han, CL Liu, X Huang, XT AF Ma, Zhiwen Qin, Wenping Wang, Zhaoqi Han, Chenglong Liu, Xiang Huang, Xiaotao TI A Meta-Analysis of Soil Organic Carbon Response to Livestock Grazing in Grassland of the Tibetan Plateau SO SUSTAINABILITY DT Article AB Known as the "roof of the world", the Tibetan Plateau hosts the largest pastoral alpine ecosystem in the world. Nevertheless, there is currently no consensus on how soil organic carbon (SOC) stock changes after livestock grazing on the grassland of this region. Here, a meta-analysis was performed based on 55 published studies to quantify the livestock grazing-induced changes in SOC stock (0-30 cm) in grassland on the Tibetan Plateau. The results showed that livestock grazing significantly increased bulk density by an average of 11.5%, indicating that significant soil compaction was caused by livestock grazing. In contrast, SOC content and stock significantly decreased by 14.4% and 11.9% after livestock grazing, respectively. The decline rate of SOC stock was higher in alpine meadow (-12.4%) than that in alpine steppe (-8.8%), but there was no significant difference between the two rates. The SOC stocks decreased by 10.1%, 6.2% and 20.1% under light grazing, moderate grazing and heavy grazing, respectively. The decline rate of SOC stock under moderate grazing was significantly lower than that under heavy grazing. For different livestock types, it was observed that yak grazing significantly decreased SOC stock by 15.3%. Although the decline rate induced by yak grazing was higher than those induced by Tibetan sheep grazing and mixed grazing, no significant difference was detected among them. Similarly, the grazing-induced SOC declines also did not differ significantly among subgroups of grazing season. The positive relationships between SOC stock and plant biomass indicated that the decreased plant biomass was a likely reason for the declined SOC stock under grazing condition. The findings suggested that moderate grazing with Tibetan sheep in the warm season may minimize SOC losses from grazing activities in alpine grassland on the Tibetan Plateau. C1 [Ma, Zhiwen; Qin, Wenping; Wang, Zhaoqi; Han, Chenglong; Liu, Xiang] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Huang, Xiaotao] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Reg Lab Qinghai, Xining 810008, Peoples R China. [Huang, Xiaotao] Chinese Acad Sci, Key Lab Adapt & Evolut Plateau Biota, Xining 810008, Peoples R China. RP Liu, X (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China.; Huang, XT (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Reg Lab Qinghai, Xining 810008, Peoples R China.; Huang, XT (通讯作者)，Chinese Acad Sci, Key Lab Adapt & Evolut Plateau Biota, Xining 810008, Peoples R China. EM xiangliu@qhu.edu.cn; xthuang@nwipb.cas.cn TC 0 Z9 0 PD NOV PY 2022 VL 14 IS 21 AR 14065 DI 10.3390/su142114065 UT WOS:000881635900001 DA 2023-03-23 ER PT J AU Wang, J Zhang, CY Luo, P Yang, H Mou, CX Mo, L AF Wang, Jun Zhang, Chunyan Luo, Peng Yang, Hao Mou, Chengxiang Mo, Li TI Does stress alleviation always intensify plant-plant competition? A case study from alpine meadows with simulation of both climate warming and nitrogen deposition SO ECOLOGICAL INDICATORS DT Article AB The effects of neighboring vegetation are important for plant fitness and community assembly under global change. What is less clear is how plant-plant interactions would change along the stress gradient. Our aim is to test the hypothesis that the abiotic stress alleviation induced by nitrogen (N) deposition and climate warming intensified the competitive effects of neighboring vegetation on two degradation indicator species of alpine meadows (i.e., Potentilla anserine and Ligularia virgaurea), as predicted by the popular "stress-gradient hypothesis" (SGH). A neighbor removal experiment was conducted with either N addition or artificial warming as treatments at both an alpine mesophytic meadows site (MESms) and a semi-hydric marsh meadows site (SHMms) on the southeastern Tibetan Plateau. The net neighbor effects on both P. anserine and L. virgaurea were extreme and moderate competition in MESms, respectively, but were mild facilitation in SHMms. In line with the SGH, both N addition and warming intensified the neighbor competitive effects on L. virgaurea in MESms and weakened the neighbor facilitative effects on L. virgaurea in SHMms. However, in contrast to the SGH, the neighbor competitive effects on P. anserine in MESms were weakened by both N addition and warming. Furthermore, the neighbor facilitative effects on P. anserine in SHMms were weakened by N addition but were not changed by warming. These diverse plant interaction-environmental gradient relationships were likely induced by the joint effects of stress type, plant strategy in response to stress and natural intensity of neighbor effects. It may be helpful to take these factors into consideration for further refinement of the SGH. C1 [Wang, Jun] China West Normal Univ, Inst Environm Sci, Nanchong, Sichuan, Peoples R China. [Zhang, Chunyan] West Normal Univ, Key Lab Southwest China Wildlife Resources Conserv, Minist Educ China, Nanchong, Sichuan, Peoples R China. [Wang, Jun; Luo, Peng; Yang, Hao] Chinese Acad Sci, Chengdu Inst Biol, Chengdu, Sichuan, Peoples R China. [Mou, Chengxiang] Chengdu Normal Univ, Coll Chem & Life Sci, Sichuan Prov Key Lab Dev & Utilizat Characterist H, Chengdu, Sichuan, Peoples R China. [Mo, Li] Sichuan Key Lab Conservat Biol Endangered Wildlife, Chengdu Res Base Giant Panda Breeding, Chengdu, Sichuan, Peoples R China. RP Zhang, CY (通讯作者)，West Normal Univ, Key Lab Southwest China Wildlife Resources Conserv, Minist Educ China, Nanchong, Sichuan, Peoples R China.; Luo, P (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Chengdu, Sichuan, Peoples R China. EM zhangchunyan1988@163.com; Luopeng@cib.ac.cn TC 0 Z9 0 PD NOV PY 2022 VL 144 AR 109510 DI 10.1016/j.ecolind.2022.109510 UT WOS:000870515000001 DA 2023-03-23 ER PT J AU Wang, Q Wan, J Li, HD Liu, B Tao, K Jin, H Hou, TP AF Wang, Qi Wan, Jun Li, Haodong Liu, Bo Tao, Ke Jin, Hong Hou, Taiping TI Effects of disturbances by plateau pikas on soil microbial communities in an alpine ecosystem of the southeast Qinghai-Tibetan plateau, China SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB Small burrowing herbivores often disturb the grassland soil. Although the plateau pika (Ochotona curzoniae) is widespread in alpine meadows in the Qinghai-Tibet Plateau, their detailed effects on ecosystem properties are not well-established. In this study, we investigated the effects of the densities of plateau pikas on plant char-acteristics, soil properties, and the composition and diversity of soil microbial communities. Plant coverage, height, aboveground biomass, and belowground biomass decreased with an increase in the densities of active plateau pika burrows. Additionally, pika disturbances led to distinct changes in soil moisture, soil bulk density (SBD), total phosphorus (TP), NH4+-N, available phosphorus (AP), and available potassium (AK) contents. Soil moisture, TP and AK contents were highest under moderate plateau pika disturbance levels, whereas the SBD and AP content were highest under the highest active burrow density. However, soil microbial diversity, as deter-mined by high-throughput sequencing, did not differ significantly among pika disturbance levels. Linear discriminant analysis Effect Size revealed that biomarker bacteria for various levels of disturbances belong to Proteobacteria, Bacteroidetes, and Firmicutes, and most biomarker bacteria were found at moderate disturbance level (D2), while biomarker fungi belong to Ascomycota and Basidiomycota, and most biomarker fungi were found in the highest plateau pika disturbance level (D4). Pika disturbances significantly influenced the microbial community, possibly via alterations in the belowground biomass, SBD, AK and TP contents. Thus, plateau pika disturbances significantly influenced the plant and soil properties and microbial community structure. C1 [Wang, Qi; Wan, Jun; Li, Haodong; Liu, Bo; Tao, Ke; Jin, Hong; Hou, Taiping] Sichuan Univ, Coll Life Sci, Key Lab Bioresource & Eco Environm, Minist Educ, Chengdu 610065, Sichuan, Peoples R China. RP Jin, H; Hou, TP (通讯作者)，Sichuan Univ, Coll Life Sci, Key Lab Bioresource & Eco Environm, Minist Educ, Chengdu 610065, Sichuan, Peoples R China. EM jinhong@scu.edu.cn; houtplab@scu.edu.cn TC 0 Z9 0 PD NOV-DEC PY 2022 VL 113 AR 103442 DI 10.1016/j.ejsobi.2022.103442 UT WOS:000866413200001 DA 2023-03-23 ER PT J AU Yang, J Zhang, M Wang, XT AF Yang, Jun Zhang, Min Wang, Xiang-tao TI Response of under-ground bud bank to degradation in an alpine meadows on the Qinghai-Tibet Plateau, China SO FRONTIERS IN PLANT SCIENCE DT Article AB Exploring the diversity and formation mechanism of under-ground bud banks is essential for understanding the renewal of plant populations and community succession. However, there are few studies on the response of bud bank size and composition to different degradation gradients in alpine meadows. In view of this, we investigated the size and composition of bud bank under four degradation gradients (non-degraded:ND, lightly degraded:LD, moderately degraded:MD, and heavily degraded:HD) caused by overgrazing in a typical alpine meadow in Tibet, China, using a unit area excavation sampling method, and analyzed the correlation between above-ground plant community composition and bud bank density. Our results showed that: (i) in the ND alpine meadow, rhizome buds were dominant, in the LD, tiller buds were dominant, and in the MD, root-sprouting buds were dominant; (ii) total bud bank and cyperaceae bud density decreased with increasing degradation gradient, the density of leguminosae was insignificant in each degradation gradient, and the density of gramineae and forb were dominant in LD and MD meadows, respectively; (iii) total bud bank density was significantly and positively correlated with total above-ground biomass in the LD gradient, tiller bud density was significantly positively correlated with the species diversity index of above-ground vegetation under the ND gradient, rhizome bud density was significantly and positively correlated with total above-ground biomass in the LD gradient, and root-sprouting density was significantly negatively correlated with total above-ground biomass in ND meadows, but was significantly positively correlated with the species diversity index of the LD gradient. Therefore, our research shows that rhizome buds are more important in ND meadow habitats, tiller buds are more important in LD meadow habitats, and root-sprouting buds are more important in MD meadows. The response of bud banks to degradation gradient varies with different types of bud banks and different functional groups of plants, and the survival strategy of bud banks is of great value for community restoration and regeneration, which should be paid more attention to in subsequent alpine meadow research. C1 [Yang, Jun] Chinese Acad Sci, Chongqing Inst Green & Intelligent Technol, Chongqing, Peoples R China. [Yang, Jun] Univ Chinese Acad Sci, Beijing, Peoples R China. [Yang, Jun; Wang, Xiang-tao] Tibet Agr & Anim Husb Univ, Coll Anim Sci, Nyingchi, Peoples R China. [Zhang, Min] China West Normal Univ, Coll Life Sci, Nanchong, Peoples R China. [Wang, Xiang-tao] Lanzhou Univ, Qiangtang Alpine Grassland Ecosyst Res Stn, Tibet Agr & Anim Husb Univ, Nyingchi, Peoples R China. [Wang, Xiang-tao] Collaborat Innovat Ctr Ecol Grassland Anim Husb Ti, Nyingchi, Peoples R China. RP Wang, XT (通讯作者)，Tibet Agr & Anim Husb Univ, Coll Anim Sci, Nyingchi, Peoples R China.; Wang, XT (通讯作者)，Lanzhou Univ, Qiangtang Alpine Grassland Ecosyst Res Stn, Tibet Agr & Anim Husb Univ, Nyingchi, Peoples R China.; Wang, XT (通讯作者)，Collaborat Innovat Ctr Ecol Grassland Anim Husb Ti, Nyingchi, Peoples R China. EM wangxt@xza.edu.cn TC 0 Z9 0 PD NOV 1 PY 2022 VL 13 AR 1013331 DI 10.3389/fpls.2022.1013331 UT WOS:000885201700001 DA 2023-03-23 ER PT J AU Zhao, P Xu, XY Tang, JN Jiang, SX AF Zhao, Peng Xu, Xianying Tang, Jinnian Jiang, Shengxiu TI Relationship between species distribution of sandy alpine grasslands and microtopography in the source regions of Yangtze river SO FRONTIERS IN ENVIRONMENTAL SCIENCE DT Article AB Dynamic of sandy alpine grasslands affect the progress and reversal of desertification in source regions of the Yangtse Rivers. To understand geomorphic driving mechanism of species distribution pattern, we examined the species compositions and delineated the most important landform factors influencing species distribution of sandy alpine grassland using two-way indicator species analysis (TWINSPAN), detrended correspondence analysis (DCA), and canonical correspondence analysis (CCA). Field survey were conducted in summer of 2016 using stratified random methods in hilly sloped lands, floodplains, foothills, and valley land of study region. In total, 29 plant species grouped into 27 genera and 16 families were identified. Leymus secalinus, Elymus dahuricus and Corispermum declinatum are the dominant species of sandy alpine grassland communities in different microtopography. The present vegetation reflected xerosere character, which indicated that desertification of alpine grassland is in progress. Standard frequency distribution of species varied with different microtopography, the proportion of dominant species was generally lower than rare species, and the vegetation community was in a highly successional stage. Seven groups were distinguished through TWINSPAN, distribution of which in the DCA ordination graph showed species with similar ecotype is clustered together. The results of the CCA ordination revealed that slope and aspect are the dominant factors among microtopography determining the species distribution of sandy alpine grassland. C1 [Zhao, Peng; Xu, Xianying; Jiang, Shengxiu] Gansu Desert Control Res Inst, State Key Lab Breeding Base Desertificat & Aeolian, Lanzhou, Peoples R China. [Zhao, Peng] Chinese Acad Sci, Key Lab Desert & Desertificat, Lanzhou, Peoples R China. [Zhao, Peng] Lanzhou Univ, Collaborat Innovat Ctr Western Ecol Safety, Lanzhou, Peoples R China. [Xu, Xianying; Tang, Jinnian] Gansu Minqin Natl Field Observat & Res Stn Ecosyst, Minqin, Peoples R China. RP Xu, XY (通讯作者)，Gansu Desert Control Res Inst, State Key Lab Breeding Base Desertificat & Aeolian, Lanzhou, Peoples R China.; Xu, XY (通讯作者)，Gansu Minqin Natl Field Observat & Res Stn Ecosyst, Minqin, Peoples R China. EM xyingxu@163.com TC 0 Z9 0 PD OCT 31 PY 2022 VL 10 AR 934483 DI 10.3389/fenvs.2022.934483 UT WOS:000885061100001 DA 2023-03-23 ER PT J AU Pan, JX Wang, JS Tian, DS Zhang, RY Li, Y Song, L Yang, JM Wei, CX Niu, SL AF Pan, Junxiao Wang, Jinsong Tian, Dashuan Zhang, Ruiyang Li, Yang Song, Lei Yang, Jiaming Wei, Chunxue Niu, Shuli TI Biotic factors dominantly determine soil inorganic carbon stock across Tibetan alpine grasslands SO SOIL DT Article AB The soil inorganic carbon (SIC) pool is a major component of soil carbon (C) pools, and clarifying the predictors of SIC stock is urgent for decreasing soil C losses and maintaining soil health and ecosystem functions. However, the drivers and their relative effects on the SIC stock at different soil depths remain largely unexplored. Here, we conducted a large-scale sampling to investigate the effects and relative contributions of abiotic (climate and soil) and biotic (plant and microbe) drivers on the SIC stock between topsoils (0-10 cm) and subsoils (20-30 cm) across Tibetan alpine grasslands. Results showed that the SIC stock had no significant differences between the topsoil and subsoil. The SIC stock showed a significant increase with altitude, pH and sand proportion, but declined with mean annual precipitation (MAP), plant aboveground biomass (PAB), plant coverage (PC), root biomass (RB), available nitrogen (AN), microbial biomass carbon (MBC), and bacterial abundance (BA) and fungal gene abundance (FA). For both soil layers, biotic factors had larger effects on the SIC stock than abiotic factors did. However, the relative importance of these determinants varied with soil depth, with the effects of plant and microbial variables on SIC stock weakening with soil depth, whereas the importance of climatic and edaphic variables increased with soil depth. Specifically, BA, FA and PC played dominant roles in regulating SIC stock in the topsoil, while soil pH contributed largely to the variation of SIC stock in the subsoil. Our findings highlight differential drivers over SIC stock with soil depth, which should be considered in biogeochemical models for better simulating and predicting SIC dynamics and its feedbacks to environmental changes. C1 [Pan, Junxiao; Wang, Jinsong; Tian, Dashuan; Zhang, Ruiyang; Li, Yang; Song, Lei; Yang, Jiaming; Wei, Chunxue; Niu, Shuli] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Song, Lei; Niu, Shuli] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. RP Wang, JS; Niu, SL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China.; Niu, SL (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM wangjinsong@igsnrr.ac.cn; sniu@igsnrr.ac.cn TC 1 Z9 1 PD OCT 28 PY 2022 VL 8 IS 2 BP 687 EP 698 DI 10.5194/soil-8-687-2022 UT WOS:000876078300001 DA 2023-03-23 ER PT J AU Wei, WR Zhang, Y Tang, ZM An, SH Zhen, QY Qin, MS He, JD Oosthuizen, MK AF Wei, Wanrong Zhang, Yan Tang, Zhongmin An, Shenghui Zhen, Qiaoyan Qin, Mingsen He, Jundong Oosthuizen, Maria K. TI Suitable grazing during the regrowth period promotes plant diversity in winter pastures in the Qinghai-Tibetan plateau SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Vegetation is a crucial component of any ecosystem and to preserve the health and stability of grassland ecosystems, species diversity is important. The primary form of grassland use globally is livestock grazing, hence many studies focus on how plant diversity is affected by the grazing intensity, differential use of grazing time and livestock species. Nevertheless, the impact of the grazing time on plant diversity remains largely unexplored. We performed a field survey on the winter pastures in alpine meadows of the Qinghai-Tibetan Plateau (QTP) to examine the effects of grazing time on the vegetation traits. Livestock species, grazing stocking rates and the initiation time of the grazing were similar, but termination times of the grazing differed. The grazing termination time has a significant effect on most of the vegetation traits in the winter pastures. The vegetation height, above-ground biomass, and the Graminoids biomass was negatively related to the grazing termination time in the winter pastures. In contrast, vegetation cover and plant diversity initially increased and subsequently decreased again as the grazing termination time was extended. An extension of the grazing time did not have any effect on the biomass of forbs. Our study is the first to investigate the effects of grazing during the regrowth period on vegetation traits and imply that the plant diversity is mediated by the grazing termination time during the regrowth period in winter pastures. These findings could be used to improve the guidelines for livestock grazing management and policies of summer and winter pasture grazing of family pastures on the QTP from the perspective of plant diversity protection. C1 [Wei, Wanrong; Zhen, Qiaoyan; Qin, Mingsen] China West Normal Univ, Coll Life Sci, Key Lab Southwest China Wildlife Resources Conserv, Nanchong, Peoples R China. [Zhang, Yan] Lanzhou Univ, Natl Demonstrat Ctr Expt Grassland Sci Educ, Lanzhou, Peoples R China. [Zhang, Yan] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou, Peoples R China. [Tang, Zhongmin; An, Shenghui] Gannan Grassland Workstat Gansu Prov, Hezuo, Peoples R China. [He, Jundong] China West Normal Univ, Inst Ecol, Nanchong, Peoples R China. [He, Jundong] Adm Bur Jiuzhaigou Natl Nat Reserve, Jiuzhaigou, Peoples R China. [Oosthuizen, Maria K.] Univ Pretoria, Dept Zool & Entomol, Hatfield, South Africa. [Oosthuizen, Maria K.] Univ Pretoria, Mammal Res Inst, Hatfield, South Africa. RP He, JD (通讯作者)，China West Normal Univ, Inst Ecol, Nanchong, Peoples R China.; He, JD (通讯作者)，Adm Bur Jiuzhaigou Natl Nat Reserve, Jiuzhaigou, Peoples R China.; Oosthuizen, MK (通讯作者)，Univ Pretoria, Dept Zool & Entomol, Hatfield, South Africa.; Oosthuizen, MK (通讯作者)，Univ Pretoria, Mammal Res Inst, Hatfield, South Africa. EM jundhe@163.com; moosthuizen@zoology.up.ac.za TC 0 Z9 0 PD OCT 18 PY 2022 VL 10 AR 991967 DI 10.3389/fevo.2022.991967 UT WOS:000878353700001 DA 2023-03-23 ER PT J AU Cui, K Qin, XT AF Cui, Kai Qin, Xiaotong TI Landslide risk assessment of frozen soil slope in Qinghai Tibet Plateau during spring thawing period under the coupling effect of moisture and heat SO NATURAL HAZARDS DT Article AB In recent years, with the global warming, the unfrozen water content of permafrost slope increases year by year. The decrease of slope stability is a great threat to the engineering construction in permafrost area. In this study, the south piedmont slope of Bayan Kara Mountain is taken as the research object. Through the field water and temperature monitoring of different positions and depths of the slope, the seasonal and interannual water change characteristics of the slope were analyzed. Combined with indoor shear strength test, numerical simulation and monitoring data, the moisture, temperature and stability of frozen soil slope in spring thawing period were analyzed. The analysis results show that: Water content and freeze-thaw cycles have great influence on the shear strength parameters at the interface. The slope moisture change in the region is divided into four stages, the water decline stage, the low water content stage, the water rise stage and the high water content stage. The freeze-thaw cycle and precipitation are the main reasons for the water change in each stage. From the middle of May to the middle of June is the high risk period of slope instability. The spring thaw landslide is dominated by shallow surface landslide, and the sliding surface is shallow. C1 [Cui, Kai] Chengdu Univ Technol, State Key Lab Geohazard Prevent & Geoenvironm Pro, Chengdu, Sichuan, Peoples R China. [Cui, Kai] Southwest Jiaotong Univ, Key Lab High Speed Railway Engn, Minist Educ, Chengdu, Sichuan, Peoples R China. [Qin, Xiaotong] Southwest Jiaotong Univ, Sch Civil Engn, Chengdu, Sichuan, Peoples R China. RP Cui, K (通讯作者)，Chengdu Univ Technol, State Key Lab Geohazard Prevent & Geoenvironm Pro, Chengdu, Sichuan, Peoples R China.; Cui, K (通讯作者)，Southwest Jiaotong Univ, Key Lab High Speed Railway Engn, Minist Educ, Chengdu, Sichuan, Peoples R China. EM cuikai@swjtu.edu.cn TC 1 Z9 1 PD FEB PY 2023 VL 115 IS 3 BP 2399 EP 2416 DI 10.1007/s11069-022-05646-8 EA OCT 2022 UT WOS:000866300500003 DA 2023-03-23 ER PT J AU Ehlers, TA Chen, DL Appel, E Bolch, T Chen, FH Diekmann, B Dippold, MA Giese, M Guggenberger, G Lai, HW Li, X Liu, JG Liu, YQ Ma, YM Miehe, G Mosbrugger, V Mulch, A Piao, SL Schwalb, A Thompson, LG Su, ZB Sun, H Yao, TD Yang, XX Yang, K Zhu, LP AF Ehlers, Todd A. Chen, Deliang Appel, Erwin Bolch, Tobias Chen, Fahu Diekmann, Bernhard Dippold, Michaela A. Giese, Markus Guggenberger, Georg Lai, Hui -Wen Li, Xin Liu, Junguo Liu, Yongqin Ma, Yaoming Miehe, Georg Mosbrugger, Volker Mulch, Andreas Piao, Shilong Schwalb, Antje Thompson, Lonnie G. Su, Zhongbo Sun, Hang Yao, Tandong Yang, Xiaoxin Yang, Kun Zhu, Liping TI Past, present, and future geo-biosphere interactions on the Tibetan Plateau and implications for permafrost SO EARTH-SCIENCE REVIEWS DT Article AB Interactions between the atmosphere, biosphere, cryosphere, hydrosphere, and geosphere are most active in the critical zone, a region extending from the tops of trees to the top of unweathered bedrock. Changes in one or more of these spheres can result in a cascade of changes throughout the system in ways that are often poorly understood. Here we investigate how past and present climate change have impacted permafrost, hydrology, and ecosystems on the Tibetan Plateau. We do this by compiling existing climate, hydrologic, cryosphere, biosphere, and geologic studies documenting change over decadal to glacial-interglacial timescales and longer. Our emphasis is on showing present-day trends in environmental change and how plateau ecosystems have largely flourished under warmer and wetter periods in the geologic past. We identify two future pathways that could lead to either a favorable greening or unfavorable degradation and desiccation of plateau ecosystems. Both paths are plausible given the available evidence. We contend that the key to which pathway future generations experience lies in what, if any, human intervention measures are implemented. We conclude with suggested management strategies that can be implemented to facilitate a future greening of the Tibetan Plateau. C1 [Ehlers, Todd A.; Appel, Erwin; Dippold, Michaela A.] Univ Tubingen, Dept Geosci, D-72076 Tubingen, Germany. [Chen, Deliang; Giese, Markus; Lai, Hui -Wen] Univ Gothenburg, Dept Earth Sci, S-40530 Gothenburg, Sweden. [Bolch, Tobias] Univ St Andrews, Sch Geog & Sustainable Dev, St Andrews KY16 9AL, Scotland. [Chen, Fahu] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst, Grp Alpine Paleoecol & Human Adaptat ALPHA, Beijing 100101, Peoples R China. [Diekmann, Bernhard] Alfred Wegener Inst Helmholtz, Zent Polar und Meeresforschung, Telegrafenberg A45, D-14473 Potsdam, Germany. [Guggenberger, Georg] Leibniz Univ Hannover, Inst Soil Sci, Herrenhauser Str 2, D-30419 Hannover, Germany. [Li, Xin; Zhu, Liping] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. [Liu, Junguo] Southern Univ Sci & Technol, Sch Environm Sci & Engn, Shenzhen 518055, Peoples R China. [Liu, Yongqin] Lanzhou Univ, Ctr Pan Pole Environm 3, Lanzhou 730000, Peoples R China. [Ma, Yaoming] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst, Land Atmosphere Interact & its Climat Effects Grp, Beijing 100101, Peoples R China. [Ma, Yaoming] Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China. [Ma, Yaoming] Lanzhou Univ, Coll Atmospher Sci, Lanzhou 730000, Peoples R China. [Miehe, Georg] Marburg Univ, Fac Geog, Deutschhausstr 10, D-35032 Marburg, Germany. [Mosbrugger, Volker] Senckenberg Gesell Nat Forsch, Senckenberganlage 25, D-60325 Frankfurt, Germany. [Mulch, Andreas] Senckenberg Biodivers & Climate Res Ctr, Senckenberganlage 25, D-60325 Frankfurt, Germany. [Piao, Shilong] Peking Univ, Sino French Inst Earth Syst Sci, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. [Schwalb, Antje] Tech Univ Carolo Wilhelmina Braunschweig, Inst Geosyst & Bioindicat, D-38106 Braunschweig, Germany. [Thompson, Lonnie G.] Ohio State Univ, Climate Res Ctr, Sch Earth Sci & Byrd Polar, Columbus, OH 43210 USA. [Su, Zhongbo] Univ Twente, Fac Geoinformat Sci & Earth Observat ITC, Enschede, Netherlands. [Sun, Hang] Chinese Acad Sci, Kunming Inst Bot, CAS Key Lab Plant Divers & Biogeog East Asia, Kunming 650201, Peoples R China. [Yao, Tandong] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst, Resources & Environm, Beijing, Peoples R China. [Yang, Xiaoxin] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. [Yang, Kun] Tsinghua Univ, Inst Global Change Studies, Dept Earth Syst Sci, Minist Educ Key Lab Earth Syst Modeling, Beijing, Peoples R China. [Mulch, Andreas] Goethe Univ Frankfurt, Inst Geosci, D-60438 Frankfurt, Germany. RP Ehlers, TA (通讯作者)，Univ Tubingen, Dept Geosci, D-72076 Tubingen, Germany. EM todd.ehlers@uni-tuebingen.de; deliang@gvc.gu.se; erwin.appel@uni-tuebingen.de; tobias.bolch@st-andrews.ac.uk; fhchen@itpcas.ac.cn; bernhard.diekmann@awi.de; michaela.dippold@uni-tuebingen.de; markus.giese@gu.se; guggenberger@ifbk.uni-hannover.de; hui-wen.lai@gu.se; xinli@itpcas.ac.cn; liujg@sustech.edu.cn; yql@lzu.edu.cn; ymma@itpcas.ac.cn; miehe@staff.uni-marburg.de; vj.mosbrugger@senckenberg.de; andreas.mulch@senckenberg.de; slpiao@pku.edu.cn; antje.schwalb@tu-braunschweig.de; thomson.3@osu.edu; z.su@utwente.nl; sunhang@mail.kib.ac.cn; tdyao@itpcas.ac.cn; yangk@tsinghua.edu.cn; yangk@tsinghua.edu.cn; lpzhu@itpcas.ac.cn TC 1 Z9 1 PD NOV PY 2022 VL 234 AR 104197 DI 10.1016/j.earscirev.2022.104197 EA OCT 2022 UT WOS:000879068000001 DA 2023-03-23 ER PT J AU Li, B Jia, GB Wen, DX Zhao, XX Zhang, JX Xu, Q Zhao, XL Jiang, N Liu, ZJ Wang, YC AF Li, Bin Jia, Gaobin Wen, Dongxu Zhao, Xiuxin Zhang, Junxing Xu, Qing Zhao, Xialing Jiang, Nan Liu, Zhenjiang Wang, Yachun TI Rumen microbiota of indigenous and introduced ruminants and their adaptation to the Qinghai-Tibetan plateau SO FRONTIERS IN MICROBIOLOGY DT Review AB The grassland in the Qinghai-Tibetan plateau provide habitat for many indigenous and introduced ruminants which perform important ecological functions that impact the whole Qinghai-Tibetan plateau ecosystem. These indigenous Tibetan ruminants have evolved several adaptive traits to withstand the severe environmental conditions, especially cold, low oxygen partial pressure, high altitude, strong UV radiation, and poor forage availability on the alpine rangelands. Despite the challenges to husbandry associated with the need for enhanced adaptation, several domesticated ruminants have also been successfully introduced to the alpine pasture regions to survive in the harsh environment. For ruminants, these challenging conditions affect not only the host, but also their commensal microbiota, especially the diversity and composition of the rumen microbiota; multiple studies have described tripartite interactions among host-environment-rumen microbiota. Thus, there are significant benefits to understanding the role of rumen microbiota in the indigenous and introduced ruminants of the Qinghai-Tibetan plateau, which has co-evolved with the host to ensure the availability of specific metabolic functions required for host survival, health, growth, and development. In this report, we systemically reviewed the dynamics of rumen microbiota in both indigenous and introduced ruminants (including gut microbiota of wild ruminants) as well as their structure, functions, and interactions with changing environmental conditions, especially low food availability, that enable survival at high altitudes. We summarized that three predominant driving factors including increased VFA production, enhanced fiber degradation, and lower methane production as indicators of higher efficiency energy harvest and nutrient utilization by microbiota that can sustain the host during nutrient deficit. These cumulative studies suggested alteration of rumen microbiota structure and functional taxa with genes that encode cellulolytic enzymes to potentially enhance nutrient and energy harvesting in response to low quality and quantity forage and cold environment. Future progress toward understanding ruminant adaptation to high altitudes will require the integration of phenotypic data with multi-omics analyses to identify host-microbiota co-evolutionary adaptations enabling survival on the Qinghai-Tibetan plateau. C1 [Li, Bin; Jia, Gaobin; Wen, Dongxu; Zhao, Xialing] Tibet Acad Agr & Anim Husb Sci, Inst Anim Husb & Vet, Lhasa, Peoples R China. [Li, Bin; Zhao, Xiuxin; Zhang, Junxing; Wang, Yachun] Ningxia Univ, Agr Coll, Yinchuan, Peoples R China. [Jia, Gaobin; Jiang, Nan] Dalian Univ, Coll Life Sci & Technol, Dalian Econ Technol Dev Zone, Dalian, Peoples R China. [Xu, Qing] Beijing Jiaotong Univ, Inst Life Sci & Bioengn, Beijing, Peoples R China. [Liu, Zhenjiang] Jilin Univ, Sch Life Sci, Natl Engn Lab AIDS Vaccine, Changchun, Peoples R China. [Wang, Yachun] China Agr Univ, Coll Anim Sci & Technol, Lab Anim Genet Breeding & Reprod, Natl Engn Lab Anim Breeding, Beijing, Peoples R China. RP Li, B (通讯作者)，Tibet Acad Agr & Anim Husb Sci, Inst Anim Husb & Vet, Lhasa, Peoples R China.; Li, B; Wang, YC (通讯作者)，Ningxia Univ, Agr Coll, Yinchuan, Peoples R China.; Liu, ZJ (通讯作者)，Jilin Univ, Sch Life Sci, Natl Engn Lab AIDS Vaccine, Changchun, Peoples R China.; Wang, YC (通讯作者)，China Agr Univ, Coll Anim Sci & Technol, Lab Anim Genet Breeding & Reprod, Natl Engn Lab Anim Breeding, Beijing, Peoples R China. EM xukesuolibin@163.com; zhenjliu@jlu.edu.cn; wangyachun@cau.edu.cn TC 0 Z9 0 PD OCT 10 PY 2022 VL 13 AR 1027138 DI 10.3389/fmicb.2022.1027138 UT WOS:000874605900001 DA 2023-03-23 ER PT J AU Wang, XY Cao, ZY Wang, CY Xu, L Zong, N Zhang, JJ He, NP AF Wang, Xinyu Cao, Zhiyuan Wang, Chuanyu Xu, Li Zong, Ning Zhang, Jinjing He, Nianpeng TI Influence of simulated warming on soil nitrogen fractions in a Tibetan alpine meadow SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Purpose Tibetan Plateau is ecologically fragile and sensitive region to global climate change. However, the impacts of climate change on nitrogen (N) cycling in soil remain unclear, which have restricted our knowledge of how N cycling in alpine ecosystems responds to climate change in the future. Methods In this study, a 5-year field simulated warming experiment using open top chambers was performed in a Tibetan alpine meadow to explore the impacts of winter warming (WW) and year-round warming (YW) on total N and N fractions in soil. The relationships between N fractions and environmental factors were evaluated. Results Relative to unwarmed control (CK), WW and YW did not significantly affect total N, NH4+-N, NO3--N, and total organic N contents. The alkali-hydrolyzable N and acid-hydrolyzable N (ammonia N, amino acid N, amino sugar N, and hydrolyzable unknown N) contents were significantly lower while acid-insoluble N content was significantly higher in WW and YW than in CK. Redundancy analysis showed that plant aboveground biomass was the most significant factor in shaping total N and N fractions. Structural equation modeling showed that fungi had direct negative effect but actinomycetes exhibited direct positive effect on hydrolyzable unknown N, which exhibited direct positive effect on plant aboveground biomass. Conclusion Our results suggested that climate warming promoted accumulation of highly stable organic N fraction, which may cause the decline of soil N supplying capacity. This study provides a novel understanding about the responses of alpine grassland to future climate change in terms of N cycling. C1 [Wang, Xinyu; Cao, Zhiyuan; Wang, Chuanyu; Zhang, Jinjing] Jilin Agr Univ, Coll Resource & Environm Sci, Key Lab Soil Resource Sustainable Utilizat Jilin, Changchun 130118, Peoples R China. [Xu, Li; Zong, Ning; He, Nianpeng] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [He, Nianpeng] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [He, Nianpeng] Northeast Forestry Univ, Ctr Ecol Res, Harbin 150040, Peoples R China. RP Zhang, JJ (通讯作者)，Jilin Agr Univ, Coll Resource & Environm Sci, Key Lab Soil Resource Sustainable Utilizat Jilin, Changchun 130118, Peoples R China.; He, NP (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China.; He, NP (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China.; He, NP (通讯作者)，Northeast Forestry Univ, Ctr Ecol Res, Harbin 150040, Peoples R China. EM zhangjinjing@126.com; henp@igsnrr.ac.cn TC 0 Z9 0 PD FEB PY 2023 VL 23 IS 2 BP 646 EP 656 DI 10.1007/s11368-022-03350-5 EA OCT 2022 UT WOS:000864973000002 DA 2023-03-23 ER PT J AU Duan, CW Li, XL Li, CY Yang, PN Shi, Y Chai, Y Xu, WY AF Duan, Chengwei Li, Xilai Li, Chengyi Yang, Pengnian Shi, Yan Chai, Yu Xu, Wenyin TI Analysis on the soil physical, chemical, and microbial community properties of different alpine meadow patches in the Source Zone of the Yellow West China SO ECOLOGICAL INDICATORS DT Article AB Severe degradation of alpine meadow in the Source Zone of the Yellow River (SZYR) seriously affects the stability and sustainability of the local grassland ecosystem. Although some progress has been made in understanding the degradation process, mechanism and restoration, existing restoration technologies do not target at topographic and hydrothermal conditions, resulting in instability and poor sustainability of the restored ecosystem. This study quantified the effects of grassland degradation severity (non-degraded patch (NP), vegetated patch (VP), bare patch (BP)) on the soil physical, chemical properties and microbial community composition and their in-teractions in the alpine meadow in the SZYR on the Eastern Qinghai-Tibet Plateau, West China. Results showed that as the degradation severity worsens from NP to BP, soil moisture, total porosity, electrical conductivity, and root biomass decreased significantly, while soil bulk density and permeability increased significantly. The contents of soil organic carbon, total nitrogen and total phosphorus decreased significantly with the enlargement of meadow patches. There were significant differences in community structure and functional microorganisms of soil bacteria and fungi in different meadow patches. In conclusion, strategies such as replanting local grass species, adding organic fertilizer and microbial fertilizers and increasing soil compaction intensity of patches to maintain soil moisture, should be considered for restoring the degraded meadow patches. C1 [Duan, Chengwei; Li, Xilai; Li, Chengyi; Yang, Pengnian; Chai, Yu; Xu, Wenyin] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. [Duan, Chengwei; Li, Xilai; Li, Chengyi; Yang, Pengnian; Chai, Yu; Xu, Wenyin] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Qinghai, Peoples R China. [Shi, Yan] Univ Auckland, Sch Environm, Auckland 1010, New Zealand. [Li, Xilai] Qinghai Univ, Coll Agr & Anim Husb, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. RP Li, XL (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. EM xilai-li@163.com TC 0 Z9 0 PD NOV PY 2022 VL 144 AR 109531 DI 10.1016/j.ecolind.2022.109531 EA OCT 2022 UT WOS:000873987400006 DA 2023-03-23 ER PT J AU Qi, Q Zhao, JS Tian, RM Zeng, YF Xie, CY Gao, Q Dai, TJ Wang, H He, JS Konstantinidis, KT Yang, YF Zhou, JZ Guo, X AF Qi, Qi Zhao, Jianshu Tian, Renmao Zeng, Yufei Xie, Changyi Gao, Qun Dai, Tianjiao Wang, Hao He, Jin-Sheng Konstantinidis, Konstantinos T. Yang, Yunfeng Zhou, Jizhong Guo, Xue TI Microbially enhanced methane uptake under warming enlarges ecosystem carbon sink in a Tibetan alpine grassland SO GLOBAL CHANGE BIOLOGY DT Article AB The alpine grasslands of the Tibetan Plateau store 23.2 Pg soil organic carbon, which becomes susceptible to microbial degradation with climate warming. However, accurate prediction of how the soil carbon stock changes under future climate warming is hampered by our limited understanding of belowground complex microbial communities. Here, we show that 4 years of warming strongly stimulated methane (CH4) uptake by 93.8% and aerobic respiration (CO2) by 11.3% in the soils of alpine grassland ecosystem. Due to no significant effects of warming on net ecosystem CO2 exchange (NEE), the warming-stimulated CH4 uptake enlarged the carbon sink capacity of whole ecosystem. Furthermore, precipitation alternation did not alter such warming effects, despite the significant effects of precipitation on NEE and soil CH4 fluxes were observed. Metagenomic sequencing revealed that warming led to significant shifts in the overall microbial community structure and the abundances of functional genes, which contrasted to no detectable changes after 2 years of warming. Carbohydrate utilization genes were significantly increased by warming, corresponding with significant increases in soil aerobic respiration. Increased methanotrophic genes and decreased methanogenic genes were observed under warming, which significantly (R-2 = .59, p < .001) correlated with warming-enhanced CH4 uptakes. Furthermore, 212 metagenome-assembled genomes were recovered, including many populations involved in the degradation of various organic matter and a highly abundant methylotrophic population of the Methyloceanibacter genus. Collectively, our results provide compelling evidence that specific microbial functional traits for CH4 and CO2 cycling processes respond to climate warming with differential effects on soil greenhouse gas emissions. Alpine grasslands may play huge roles in mitigating climate warming through such microbially enhanced CH4 uptake. C1 [Qi, Qi; Zeng, Yufei; Xie, Changyi; Gao, Qun; Dai, Tianjiao; Yang, Yunfeng; Guo, Xue] Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing, Peoples R China. [Zhao, Jianshu; Konstantinidis, Konstantinos T.] Georgia Inst Technol, Sch Civil & Environm Engn, Atlanta, GA 30332 USA. [Zhao, Jianshu; Konstantinidis, Konstantinos T.] Georgia Inst Technol, Sch Biol Sci, Atlanta, GA 30332 USA. [Tian, Renmao] IIT, Inst Food Safety & Hlth, Chicago, IL 60616 USA. [Wang, Hao] Lanzhou Univ, Coll Ecol, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. [He, Jin-Sheng] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. [He, Jin-Sheng] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou, Peoples R China. [He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Beijing, Peoples R China. [He, Jin-Sheng] Peking Univ, Inst Ecol, Key Lab Earth Surface Proc, Minist Educ, Beijing, Peoples R China. [Zhou, Jizhong] Univ Oklahoma, Inst Environm Genom, Norman, OK 73019 USA. [Zhou, Jizhong] Univ Oklahoma, Dept Microbiol & Plant Biol, Norman, OK 73019 USA. [Zhou, Jizhong] Lawrence Berkeley Natl Lab, Earth & Environm Sci Div, Berkeley, CA USA. RP Guo, X (通讯作者)，Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing, Peoples R China. EM guoxue0601@tsinghua.edu.cn TC 0 Z9 0 PD DEC PY 2022 VL 28 IS 23 BP 6906 EP 6920 DI 10.1111/gcb.16444 EA OCT 2022 UT WOS:000863393800001 DA 2023-03-23 ER PT J AU Qiu, DD Zhu, YP Zhang, H Fu, MD Ren, YH Li, JS AF Qiu, Dongdong Zhu, Yanpeng Zhang, Hua Fu, Mengdi Ren, Yueheng Li, Junsheng TI Strong earthquake results in regional die-off and degradation of alpine wetlands in the Qinghai-Tibet Plateau: Implications for management and restoration SO ECOLOGICAL INDICATORS DT Article AB Strong earthquakes can have negative effects on various ecosystems, including farmlands, grasslands, and coasts. However, reports of how strong earthquakes affect the biodiversity and ecosystem functions of alpine wetlands are lacking. In the present study, investigations of soil and aquatic plants and snails were conducted to determine if and how the strong M7.4 Maduo earthquake in 2021 affected the alpine wetlands in the Qinghai-Tibet Plateau. Our results demonstrated that the Maduo earthquake resulted in the infiltration of surface water in many alpine marshes or pools near the earthquake fissures, and the ability of these alpine wetlands to restore the rainwater or meltwater declined or was even lost. The long-time disappearance of surface water directly changed the envi-ronmental conditions, decreased the contents of soil moisture and various soil nutrients and increased the soil hardness and salinity, which resulted in the die-off of aquatic plants and snails, decrease in the abundance of water birds, and finally habitat degradation. The densities of alive aquatic plants and snails were positively related to the soil moisture content and some nutrient indices, and negatively related to the soil salinity. The density of alive aquatic snails was also positively related to the density of alive aquatic plants. Additionally, in the future, these dried and degraded alpine wetlands could become a potential source or sink of soil desertifi-cation. This study also provided scientific implications for the ecosystem management and restoration of alpine wetlands after strong earthquakes. The restoration and filling of adjacent earthquake fissures and the supple-mentation of surface water, plants, and macrobenthos need to be carried out after a strong earthquake to protect the biodiversity and restore the alpine wetlands. C1 [Qiu, Dongdong; Zhu, Yanpeng; Zhang, Hua; Fu, Mengdi; Ren, Yueheng; Li, Junsheng] Chinese Res Inst Environm Sci, State Key Lab Environm Criteria & Risk Assessment, Beijing 100012, Peoples R China. [Qiu, Dongdong; Zhu, Yanpeng; Zhang, Hua; Fu, Mengdi; Ren, Yueheng; Li, Junsheng] Chinese Res Inst Environm Sci, State Environm Protect Key Lab Reg Ecoproc & Funct, Beijing 100012, Peoples R China. RP Zhu, YP; Li, JS (通讯作者)，Chinese Res Inst Environm Sci, State Key Lab Environm Criteria & Risk Assessment, Beijing 100012, Peoples R China. EM zhuyp@craes.org.cn; lijsh@craes.org.cn TC 0 Z9 0 PD NOV PY 2022 VL 144 AR 109503 DI 10.1016/j.ecolind.2022.109503 EA OCT 2022 UT WOS:000874217700002 DA 2023-03-23 ER PT J AU An, H Baskin, CC Ma, MJ AF An, Hang Baskin, Carol C. Ma, Miaojun TI Nonlinear response of the soil seed bank and its role in plant community regeneration with increased grazing disturbance SO JOURNAL OF APPLIED ECOLOGY DT Article AB The soil seed bank represents valuable rebuilding capital that may rescue an ecosystem from state transition once vegetation has crossed an apparent threshold from the desired to degraded state. However, almost no research has explored the response of transient and persistent seed banks and their role in plant community regeneration along a gradient of wetlands from intact to a seriously degraded state due to increased grazing disturbance. Seven grazing disturbance levels from nondisturbed to highly degraded alpine marsh ecosystems were selected on the eastern Tibetan Plateau. Akaike information criterion (AIC) was used to select the best-fit model to predict the response of the plant community, soil seed bank and Bray-Curtis dissimilarity index to increased grazing disturbance. Both the plant community and seed bank showed a nonlinear change with increasing grazing disturbance. Species richness and seed density of the transient seed bank first decreased and then increased with increased disturbance, but the persistent seed bank showed a reverse trend, with an obvious threshold. Species composition of the persistent and transient seed banks exhibited little change compared to the plant community as disturbance increased. Similarities between both the persistent and transient seed banks and plant community also showed a nonlinear change with increased disturbance, while the persistent seed bank had a higher similarity with the plant community than the transient seed bank. Synthesis: At high grazing disturbance, persistent seed banks are more important than transient seed banks in plant community regeneration. Alpine wetland ecosystems have intrinsic resilience because the persistent seed bank has a pool of species above the threshold. However, ecosystem resilience declines if the species pool of the persistent seed bank is depleted below the threshold. The restoration potential of the seed bank has limits, and it will gradually be exhausted when species losses due to increased grazing intensity exceed the threshold of state transition. C1 [An, Hang; Ma, Miaojun] Lanzhou Univ, Coll Ecol, State Key Lab Grassland & Agroecosyst, Lanzhou, Peoples R China. [Baskin, Carol C.] Univ Kentucky, Dept Biol, Lexington, KY USA. [Baskin, Carol C.] Univ Kentucky, Dept Plant & Soil Sci, Lexington, KY USA. RP Ma, MJ (通讯作者)，Lanzhou Univ, Coll Ecol, State Key Lab Grassland & Agroecosyst, Lanzhou, Peoples R China. EM mjma@lzu.edu.cn TC 2 Z9 2 PD OCT PY 2022 VL 59 IS 10 BP 2593 EP 2603 DI 10.1111/1365-2664.14259 UT WOS:000863005700014 DA 2023-03-23 ER PT J AU Chen, T Xu, HJ Qi, XL Shan, SY Chen, SY Deng, YF AF Chen, Tian Xu, Hao-jie Qi, Xiao-lian Shan, Shu-yao Chen, Sheng-yun Deng, Yan-fang TI Temporal dynamics of satellite-derived vegetation pattern and growth in an arid inland river basin, Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Exploring alpine vegetation dynamics and its driving factors help to predict changes in hydrothermal circulations at high elevations in the future. Currently, there is a lack of systematic research on this topic in the permafrost regions at a basin scale. Spatiotemporal variations of vegetation pattern and growth estimated from satellite remote sensing images at a 30 m spatial resolution on the Google Earth Engine cloud platform were investigated in the Shule River headwater region from 2000 to 2021. The results showed shrinking trends in alpine grassland (AG) and wetland (AW) area, while an expanding trend in alpine desert (AD) area. AD moved to lower altitudes and occupied AG and AW area, possibly owing to mountain permafrost degradation and extreme precipitation. Vegetation patches became fragmented and complex, reflected by increases in patch number and shape index. Vegetation growth, as approximated by the normalized difference vegetation index (NDVI), increased significantly in 42 % of the vegetated area (p < 0.05), particularly in river valleys. In addition, NDVI was negatively correlated with solar radiation over 30 % of the vegetated area (p < 0.05). At the regional scale, vegetation NDVI was positively correlated with root-zone soil moisture and grazing intensity (p < 0.05). The findings suggested that AG and AW at their upper limit of distribution were vulnerable to soil erosion, and the inter-annual variation of vegetation growth was affected by soil moisture and grazing. Moreover, future climate warming may cause alpine vegetation decline by increasing active layer thickness in the absence of adequate precipitation supply. C1 [Chen, Tian; Xu, Hao-jie; Qi, Xiao-lian; Shan, Shu-yao] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. [Chen, Tian; Xu, Hao-jie; Qi, Xiao-lian; Shan, Shu-yao] Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China. [Chen, Tian; Xu, Hao-jie; Qi, Xiao-lian; Shan, Shu-yao] Lanzhou Univ, Engn Res Ctr Grassland Ind, Minist Educ, Lanzhou 730020, Peoples R China. [Chen, Tian; Xu, Hao-jie; Qi, Xiao-lian; Shan, Shu-yao] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. [Chen, Sheng-yun] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere & Ecoenvironm Res Stn Shule River Head, Lanzhou 730000, Peoples R China. [Chen, Sheng-yun; Deng, Yan-fang] Long Term Natl Sci Res Base Qilian Mt Natl Pk, Xining 810000, Peoples R China. RP Xu, HJ (通讯作者)，Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China.; Xu, HJ (通讯作者)，Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China.; Xu, HJ (通讯作者)，Lanzhou Univ, Engn Res Ctr Grassland Ind, Minist Educ, Lanzhou 730020, Peoples R China.; Xu, HJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. EM xuhaojie@lzu.edu.cn TC 0 Z9 0 PD OCT PY 2022 VL 38 AR e02262 DI 10.1016/j.gecco.2022.e02262 UT WOS:000889121500008 DA 2023-03-23 ER PT J AU He, CY Yan, F Wang, YJ Lu, Q AF He, Chenyang Yan, Feng Wang, Yanjiao Lu, Qi TI Spatiotemporal Variation in Vegetation Growth Status and Its Response to Climate in the Three-River Headwaters Region, China SO REMOTE SENSING DT Article AB The Three-River Headwaters Region (TRHR), located in the hinterland of the Qinghai-Tibet Plateau (QTP), is an important water-conservation and ecological-function reserve in China. Studies of the growth of vegetation in the TRHR and its response to climate under the background of global warming are of great relevance for ecological protection of the QTP. In this study, based on MOD13Q1 Enhanced Vegetation Index (EVI) data and ERA5-Land climate data, the ensemble empirical mode decomposition method, random forest algorithm, and Hurst exponent were used to detect the spatiotemporal dynamics and response to climate change in TRHR vegetation during 2000-2021. The results indicated the following. (1) Comparatively, the condition of vegetation growth was better in 2021, 2010, and 2018 and poorer in 2015, 2003, and 2008. The EVI gradually decreased from the southeast to the northwest, and the area of improved vegetation growth was larger than the area of degraded vegetation growth. (2) The area of zones with either monotonous greening or monotonous browning of vegetation was 30.30% and 6.30%, respectively, and the trend of reversed vegetation change occurred in 63.40% of the areas. The area of future degradation of vegetation in the TRHR was larger than the area of future improvement, and the risk of vegetation degradation was higher. (3) Precipitation and soil temperature are the main and secondary driving factors of vegetation change in the TRHR, respectively. Warming and humidification of the QTP climate play major roles in the improvement of vegetation growth in the TRHR. C1 [He, Chenyang; Yan, Feng; Lu, Qi] Chinese Acad Forestry, Inst Ecol Conservat & Restorat, Beijing 100091, Peoples R China. [Yan, Feng; Lu, Qi] Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. [Wang, Yanjiao] China Meteorol Adm, Natl Climate Ctr, Beijing 100081, Peoples R China. RP Yan, F (通讯作者)，Chinese Acad Forestry, Inst Ecol Conservat & Restorat, Beijing 100091, Peoples R China.; Yan, F (通讯作者)，Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. EM fyan@caf.ac.cn TC 1 Z9 1 PD OCT PY 2022 VL 14 IS 19 AR 5041 DI 10.3390/rs14195041 UT WOS:000867245200001 DA 2023-03-23 ER PT J AU Jia, YL Chen, SY Wei, PJ AF Jia, Yinglan Chen, Shengyun Wei, Peijie TI Effect of Revegetation in Extremely Degraded Grassland on Carbon Density in Alpine Permafrost Regions SO SUSTAINABILITY DT Article AB Revegetation has been proposed as an effective approach to restoring the extremely degraded grassland in the Qinghai-Tibetan Plateau (QTP). However, little is known about the effect of revegetation on ecosystem carbon density (ECD), especially in alpine permafrost regions. We compared aboveground biomass carbon density (ABCD), belowground biomass carbon density (BBCD), soil organic carbon density (SOCD), and ECD in intact alpine meadow, extremely degraded, and revegetated grasslands, as well as their influencing factors. Our results indicated that (1) ABCD, BBCD, SOCD, and ECD were significantly lower in extremely degraded grassland than in intact alpine meadow; (2) ABCD, SOCD, and ECD in revegetated grassland significantly increased by 93.46%, 16.88%, and 19.22%, respectively; (3) stepwise regression indicated that BBCD was mainly influenced by soil special gravity, and SOCD and ECD were controlled by freeze-thaw strength and soil temperature, respectively. This study provides a comprehensive survey of ECD and basic data for assessing ecosystem service functions in revegetated grassland of the alpine permafrost regions in the QTP. C1 [Jia, Yinglan; Chen, Shengyun; Wei, Peijie] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere & Ecoenvironm Res Stn Shule River Head, Lanzhou 730000, Peoples R China. [Jia, Yinglan; Wei, Peijie] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Chen, Shengyun] Qinghai Normal Univ, Acad Plateau Sci & Sustainabil, Sch Geog Sci, Xining 810008, Peoples R China. [Chen, Shengyun] Long Term Natl Sci Res Base Qilian Mt Natl Pk, Xining 810000, Peoples R China. RP Chen, SY (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere & Ecoenvironm Res Stn Shule River Head, Lanzhou 730000, Peoples R China.; Chen, SY (通讯作者)，Qinghai Normal Univ, Acad Plateau Sci & Sustainabil, Sch Geog Sci, Xining 810008, Peoples R China.; Chen, SY (通讯作者)，Long Term Natl Sci Res Base Qilian Mt Natl Pk, Xining 810000, Peoples R China. EM sychen@lzb.ac.cn TC 1 Z9 1 PD OCT PY 2022 VL 14 IS 19 AR 12575 DI 10.3390/su141912575 UT WOS:000867352900001 DA 2023-03-23 ER PT J AU Li, T Cui, LZ Lv, WC Song, XF Cui, XY Tang, L AF Li, Tong Cui, Lizhen Lv, Wencong Song, Xiufang Cui, Xiaoyong Tang, Li TI Exploring the frontiers of sustainable livelihoods research within grassland ecosystem: A scientometric analysis SO HELIYON DT Article AB Grassland degradation has become a global social-ecological problem, which seriously limits the sustainability of indigenous people's livelihoods. Bibliometrics, a type of analysis based on the Science Citation Index-Expanded (SCI-E), was therefore performed to explore the research trends and focus areas of studies on sustainable liveli-hoods (SLs). We conducted an in-depth analysis of 489 research publications and their 25,144 references from 1991 to 2020. The results show that only few papers have been published, but the number of countries and research institutions involved shows an overall imbalance. We identified eight main clusters based on keyword co-occurrence, these being studies the content of which is an important representation of current research directions in this topic. The document co-citation analysis revealed 10 research clusters, representing the frontiers of research. Clusters included the following topics: NPP (Net Primary Productivity) dynamics, global change, ecological restoration, risk indicators, livelihood strategies, smallholder systems, drought relief, sustainable land management and common pool resources. We reviewed and interpreted these clusters in depth with a view to provide an up-to-date account of the dynamics of this research. As the first scientometric evaluation of research on sustainable livelihoods in grassland ecosystems, this study provides several theoretical and practical implications for global poverty eradication research, which are of great scientific value for global sustainable development. C1 [Li, Tong; Tang, Li] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Li, Tong; Tang, Li] Griffith Univ, Ctr Planetary Hlth & Food Secur, Sch Environm & Sci, Brisbane, Qld 4111, Australia. [Cui, Lizhen; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Lv, Wencong] Univ Chinese Acad Sci, Sino Danish Coll, Sino Danish Ctr Educ & Res, Beijing 100049, Peoples R China. [Song, Xiufang] Chinese Acad Sci, Natl Sci Lib, Beijing 100190, Peoples R China. [Cui, Xiaoyong] Univ Chinese Acad Sci, Beijing Yanshan Earth Crit Zone Natl Res Stn, Beijing 101408, Peoples R China. RP Tang, L (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China.; Tang, L (通讯作者)，Griffith Univ, Ctr Planetary Hlth & Food Secur, Sch Environm & Sci, Brisbane, Qld 4111, Australia.; Cui, XY (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China.; Cui, XY (通讯作者)，Univ Chinese Acad Sci, Beijing Yanshan Earth Crit Zone Natl Res Stn, Beijing 101408, Peoples R China. EM cuixy@ucas.ac.cn; tangli@ucas.ac.cn TC 1 Z9 1 PD OCT PY 2022 VL 8 IS 10 AR e10704 DI 10.1016/j.heliyon.2022.e10704 EA OCT 2022 UT WOS:000870514600007 DA 2023-03-23 ER PT J AU Li, Y He, M Du, YZ Wang, XP Zhang, H Dai, ZC Wan, JSH Su, JQ Wang, CY Du, DL AF Li, Yan He, Min Du, Yizhou Wang, Xiupu Zhang, Hui Dai, Zhicong Wan, Justin S. H. Su, Jiquan Wang, Congyan Du, Daolin TI Indigenous PGPB Inoculant from Qinghai-Tibetan Plateau Soil Confer Drought-Stress Tolerance to Local Grass Poa annua SO INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH DT Article AB Grassland degradation in Qinghai-Tibetan Plateau (QTP) is becoming a serious environmental problem which has attracted widespread public attention. Application of plant growth promoting bacteria (PGPB) inoculant is considered as a potential strategy in helping plants cope with environmental stress. This study aimed to explore an effective functional microbial inoculant for the restoration of degenerated grasslands. Three PGPB strains (i.e., Paenibacillus tundrae TS19, Bacillus mycoides TS26 and Brevibacterium frigoritolerans TS22) characterized by outstanding osmotic tolerance, siderophore production, and plant growth promotion capacity were isolated from QTP grassland. The influence of single and mixed inoculations of three strains on the growth of Poa annua were evaluated. The results showed that water deficiency significantly inhibited plant growth and led to increased reactive oxygen species (ROS), superoxide dismutase (SOD) activity, and proline content in plant. The inoculation of PGPB could alleviate the drought stress by modifying root morphology and activating SOD activity. It is interesting that mixed inoculation of P. tundrae TS19 and B. mycoides TS26 was more effective under low and moderate drought stress, while single inoculation of P. tundrae TS19 had the best performance under high drought stress. The suitable inoculant-combination should be chosen according to the drought stress level and drought-tolerant capacity of inoculant. This study provides valuable microbial resources and guidance of inoculants selection for remediation of degraded grassland in QTP. C1 [Li, Yan; He, Min; Wang, Xiupu; Zhang, Hui; Dai, Zhicong; Wan, Justin S. H.; Wang, Congyan; Du, Daolin] Jiangsu Univ, Sch Environm & Safety Engn, Inst Environm Hlth & Ecol Secur, Zhenjiang 212013, Jiangsu, Peoples R China. [Li, Yan] Suzhou Univ Sci & Technol, Jiangsu Collaborat Innovat Ctr Technol & Mat Wate, Suzhou 215009, Jiangsu, Peoples R China. [Du, Yizhou] Univ Sydney, Fac Engn, Sch Comp Sci, J12-1 Cleveland St, Darlington, NSW 2008, Australia. [Su, Jiquan] Inner Mongolia Univ, Sch Ecol & Environm, Lab Microbial Resources, Hohhot 010021, Peoples R China. RP Dai, ZC; Du, DL (通讯作者)，Jiangsu Univ, Sch Environm & Safety Engn, Inst Environm Hlth & Ecol Secur, Zhenjiang 212013, Jiangsu, Peoples R China. EM daizhicong@163.com; ddl@ujs.edu.cn TC 0 Z9 0 PD OCT PY 2022 VL 16 IS 5 AR 85 DI 10.1007/s41742-022-00470-1 UT WOS:000852427400001 DA 2023-03-23 ER PT J AU Niu, KC Suonan, J Badingqiuying Smith, AT Lechowicz, MJ AF Niu, Kechang Suonan, Ji Badingqiuying Smith, Andrew T. Lechowicz, Martin J. TI Embedding trait-based ecology within indigenous knowledge to advance sustainable management of Tibetan rangeland SO APPLIED VEGETATION SCIENCE DT Article AB Questions Traditional pastoralists attribute high numbers of plateau pikas (Ochotona curzoniae) to impoverished soils that favor more and better forage for pika, suggesting a bottom-up control of pika density. Conversely, government policies focus on excessive numbers of this small mammalian herbivore as the primary top-down cause of degradation in Tibetan rangeland. Despite concerted campaigns to reduce pika abundance in recent decades, the sustainability of Tibetan rangelands remains uncertain. Location Alpine meadows on the Tibetan Plateau. Methods We proposed a conceptual model based on indigenous knowledge that predicted pika numbers from soil condition and plant traits. At three alpine meadow sites lightly grazed by livestock, we tested whether spatial variation in pika burrow density could be explained by changes in the functional composition of the plant community attributable to species turnover and intraspecific trait variation associated with changes in soil fertility. Results Due primarily to intraspecific trait variation, changes in the functional composition of the meadow community accounted for 56%-68% of the spatial variation in pika density, changes in the proportion of plant functional groups for 62%-74%, and changes in edaphic conditions for 71%-82%. Greater pika density was associated with a decline in soil phosphorus availability and a lower-growing vegetation profile enriched in both the quantity and quality of forage preferred by pikas. Conclusions These results, which are in accord with indigenous knowledge, suggest that compensating soil phosphorus losses and maintaining a well-calibrated grazing rotation can better manage pika populations and improve the sustainability of Tibetan rangelands. By combining trait-based ecology and traditional knowledge, our study provides new insight into both understanding the dynamic complexity of grazing regimes and managing rangeland sustainability. C1 [Niu, Kechang] Nanjing Univ, Sch Life Sci, Nanjing 210023, Peoples R China. [Suonan, Ji] Qinghai Normal Univ, Coll Life Sci, Xining, Peoples R China. [Badingqiuying] Qinghai Normal Univ, Coll Geog Sci, Xining, Peoples R China. [Smith, Andrew T.] Arizona State Univ, Sch Life Sci, Tempe, AZ USA. [Lechowicz, Martin J.] McGill Univ, Dept Biol, Montreal, PQ, Canada. RP Niu, KC (通讯作者)，Nanjing Univ, Sch Life Sci, Nanjing 210023, Peoples R China. EM kechangniu@nju.edu.cn TC 0 Z9 0 PD OCT PY 2022 VL 25 IS 4 AR e12687 DI 10.1111/avsc.12687 UT WOS:000878063800001 DA 2023-03-23 ER PT J AU Wang, RJ Wang, YJ Yan, F AF Wang, Ruijie Wang, Yanjiao Yan, Feng TI Vegetation Growth Status and Topographic Effects in Frozen Soil Regions on the Qinghai-Tibet Plateau SO REMOTE SENSING DT Article AB The Qinghai-Tibet Plateau (QTP), which is known as Earth's "Third Pole", is a driver of global climate change, and long-term monitoring of QTP vegetation can reveal changes attributable to climatic and human influences. Previous research monitoring vegetation on the QTP focused primarily on spatiotemporal variations of vegetation indices, while few studies have considered fractional vegetation cover (FVC) in relation to topographic and frozen soil factors. We used MODIS-EVI, digital elevation models, and frozen soil data to investigate topographic effects on vegetation growth status in different soil types on the QTP during 2000-2020. (1) FVC showed a trend of increase during 2000-2020, and the FVC on the QTP decreased from the southeast to the northwest in spatial distribution. FVC in permafrost regions was the lowest, followed by seasonal frozen soil areas; FVC in unfrozen areas was the highest. (2) With increasing elevation, FVC of permafrost, seasonal frozen, and unfrozen soil areas showed downward trends for each aspect. In seasonal frozen soil areas, at elevation <= 4000 m (>4000 m), FVC of sunny (shady) slopes was greater than that of shady (sunny) slopes. In permafrost regions, except at elevations of 3000-4000 m, FVC of shady slopes was greater than that of sunny slopes. In unfrozen soil areas, at elevation >4000 m, FVC of sunny slopes was obviously greater than that of shady slopes. (3) With increasing slope, FVC in seasonal frozen and permafrost soil (unfrozen soil) regions showed a trend of increase (decrease). In seasonal frozen soil areas, FVC of sunny (shady) slopes was greater than that of shady (sunny) slopes on slopes <= 6 degrees (>6 degrees). In permafrost regions, FVC of sunny slopes was less than that of shady slopes. With increasing slope, the influence of aspect became more obvious. In unfrozen soil areas, FVC of sunny slopes was slightly greater than that of shady slopes. Topographic effects especially the elevation and slope effects might significantly affect the spatiotemporal variations of vegetation growth status in frozen soil regions on the QTP. C1 [Wang, Ruijie] Northeastern Univ, Sch Resources & Mat, Qinhuangdao Branch, Qinhuangdao 066004, Hebei, Peoples R China. [Wang, Yanjiao] China Meteorol Adm, Natl Climate Ctr, Beijing 100081, Peoples R China. [Yan, Feng] Chinese Acad Forestry, Inst Ecol Conservat & Restorat, Beijing 100091, Peoples R China. [Yan, Feng] Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. RP Yan, F (通讯作者)，Chinese Acad Forestry, Inst Ecol Conservat & Restorat, Beijing 100091, Peoples R China.; Yan, F (通讯作者)，Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. EM fyan@caf.ac.cn TC 0 Z9 0 PD OCT PY 2022 VL 14 IS 19 AR 4830 DI 10.3390/rs14194830 UT WOS:000868060100001 DA 2023-03-23 ER PT J AU Zhang, ZW Han, JH Yin, HY Xue, J Jia, LZ Zhen, X Chang, JJ Wang, SK Yu, B AF Zhang, Zhiwei Han, Jiahua Yin, Huiyan Xue, Jie Jia, Lizhi Zhen, Xing Chang, Jingjing Wang, Shunke Yu, Bo TI Assessing the effects of different long-term ecological engineering enclosures on soil quality in an alpine desert grassland area SO ECOLOGICAL INDICATORS DT Article AB The soil quality assessment is the basis for evaluating the soil quality restoration status of degraded grassland and improving soil management in the enclosure areas. However, the evaluation of the effects of different long-term ecological engineering enclosures on soil quality in alpine grassland areas is still lacking. This study took soil samples of alpine grassland from the Tibet Plateau to examine the soil quality of alpine grassland and analyze the main influencing factors of soil quality under different enclosure years. Based on the soil samples from different and corresponding control plots for 10, 11, and 12 years, principal component analysis was used to screen the minimum data set (MDS) of the 12 physical and chemical properties of the soil samples. The soil quality index (SQI) was constructed to quantitatively evaluate the soil quality by the MDS with different closure years. Results show: (1) The respective grades of the soil fertility levels of nitrogen in the sample plots fenced for 10, 11, and 12 years were 4, 5, and 5. The soil fertility level of the other indicators was grade 6. (2) The 12 soil indicators had medium and low degrees of variation. Only the available phosphorus was at a strong variation level in the sample plots for 12 years. (3) The soil quality in the different enclosure years compared with the corresponding control plots became better. The different enclosure years indicated SQI (0.59 +/- 0.11) of 10 years SQI (0.50 +/- 0.04) of 12 years > SQI (0.44 +/- 0.05) of 11 years. (4) The MDS of soil quality assessment was composed of total nitrogen, total potassium, silt and total porosity. Compared with the full data set, the MDS could better replace the full data set for soil quality assessment (P < 0.01). This study found that the long-term ecological engineering enclosures have improved the soil quality of alpine grasslands. Total nitrogen and total potassium, total potassium and silt, and total potassium and silt were the main factor affecting the soil quality in 10, 11 and 12 enclosure years, respectively. C1 [Zhang, Zhiwei; Han, Jiahua; Yin, Huiyan; Zhen, Xing; Yu, Bo] Tibet Agr & Anim Husb Univ, Coll Resources & Environm Sci, Key Lab Forest Ecol Tibet Plateau, Nyingchi 860000, Peoples R China. [Xue, Jie; Wang, Shunke] Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China. [Jia, Lizhi] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. [Xue, Jie; Wang, Shunke] Cele Natl Stn Observat & Res Desert Grassland Eco, Cele 848300, Hetian, Peoples R China. [Xue, Jie; Wang, Shunke] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Zhiwei] Tibet Agr & Anim Husb Univ, Res Ctr Soil & Water Conservat Alpine Cold Reg, Nyingchi 860000, Peoples R China. [Chang, Jingjing] Xinjiang Univ, Coll Ecol & Environm, Urumqi 830017, Peoples R China. RP Xue, J (通讯作者)，Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China.; Jia, LZ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China.; Xue, J (通讯作者)，Cele Natl Stn Observat & Res Desert Grassland Eco, Cele 848300, Hetian, Peoples R China.; Xue, J (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM xuejie11@ms.xjb.ac.cn; jializhi10000@126.com TC 0 Z9 0 PD OCT PY 2022 VL 143 AR 109426 DI 10.1016/j.ecolind.2022.109426 UT WOS:000911784200006 DA 2023-03-23 ER PT J AU Zhao, JY Jiang, CL Liu, WH Ding, YY Li, GR AF Zhao, Jianyun Jiang, Chuanli Liu, Wenhui Ding, Yuanyuan Li, Guorong TI Pika disturbance intensity observation system via multidimensional stereoscopic surveying for monitoring alpine meadow SO JOURNAL OF APPLIED REMOTE SENSING DT Article AB Plateau pika (Ochotona curzoniae) is a key species of alpine meadow ecosystem in Qinghai-Tibet Plateau. In this study, an observation and classification system of plateau pika disturbance intensity was constructed by multidimensional stereoscopic surveying, visual interpretation, geostatistics, principal component analysis, and clustering analysis, which can monitor and evaluate the disturbance of plateau pika activities comprehensively, scientifically, and efficiently in the head-water region of the Yellow River. The results show that (1) digital elevation model, digital orthophoto model, and three-dimensional real scene model can extract the surface morphology information changed by pika activities such as the number of pika holes and molehills, the area and volume of molehills, the elevation variation coefficient, the surface relief, and roughness; (2) The main load factors of the plateau pika disturbance intensity index (PPDII) are the surface roughness, the area and number of the molehills, and the number of mousehole; (3) The kappa value of PPDII clustering verification was 0.866, and the clustering analysis results were consistent with reality characteristics of plateau pika activity and distribution; (4) The disturbance in Laji Mountain is mainly slight and mild, accounting for 47.6% of sampling area, and the disturbance in Henan County is mainly medium and severe, accounting for 42.6% of sampling area. The results can provide reference data for the restoration and management of alpine meadow degradation in the head-water region of the Yellow River. (c) 2022 Society of Photo-Optical Instrumentation Engineers (SPIE) C1 [Zhao, Jianyun; Jiang, Chuanli; Liu, Wenhui; Ding, Yuanyuan; Li, Guorong] Qinghai Univ, Dept Geol Engn, Xining, Peoples R China. [Zhao, Jianyun; Li, Guorong] Key Lab Cenozo Resource & Environm North Margin Q, Xining, Peoples R China. RP Zhao, JY (通讯作者)，Qinghai Univ, Dept Geol Engn, Xining, Peoples R China.; Zhao, JY (通讯作者)，Key Lab Cenozo Resource & Environm North Margin Q, Xining, Peoples R China. EM zhaojianyun1981@163.com TC 0 Z9 0 PD OCT PY 2022 VL 16 IS 4 AR 044524 DI 10.1117/1.JRS.16.044524 UT WOS:000917345800026 DA 2023-03-23 ER PT J AU Chen, H Ju, PJ Zhu, Q Xu, XL Wu, N Gao, YH Feng, XJ Tian, JQ Niu, SL Zhang, YJ Peng, CH Wang, YF AF Chen, Huai Ju, Peijun Zhu, Qiuan Xu, Xingliang Wu, Ning Gao, Yongheng Feng, Xiaojuan Tian, Jianqing Niu, Shuli Zhang, Yangjian Peng, Changhui Wang, Yanfen TI Carbon and nitrogen cycling on the Qinghai-Tibetan Plateau SO NATURE REVIEWS EARTH & ENVIRONMENT DT Review AB The Qinghai-Tibetan Plateau (QTP) has experienced atmospheric warming, cryosphere thaw and intensified human activities since the 1970s. These changes have had sometimes striking impacts on the hydrology, ecosystems and biogeochemistry of the region. In this Review, we describe carbon and nitrogen cycling on the QTP. Overall, the QTP has been a net carbon sink (with a net carbon balance of similar to 44 million tons of carbon uptake peryear) and a methane source (similar to 0.96 trillion grams per year of carbon in the form of methane, TgCH(4)-Cyr(-1)) since the 2000s. Rising temperatures, precipitation and nitrogen availability drive primary productivity increases, leading to increased carbon uptake. Conversely, these factors also increase greenhouse gas emissions, soil respiration rates and permafrost carbon mobilization, increasing carbon loss. Anthropogenic activities such as overgrazing and construction decrease plant production and soil carbon and nitrogen stocks, but restoration efforts on the QTP drive regional increases in these stocks. On balance, these changes are complex but largely offset each other. In the future, the QTP is predicted to still function as a net carbon sink, despite ongoing severe permafrost degradation. Moreover, nitrogen stocks are expected to remain relatively stable, partly related to potential future decreases in nitrogen deposition. C1 [Chen, Huai; Ju, Peijun; Wu, Ning; Gao, Yongheng] Chinese Acad Sci, Chengdu Inst Biol, Chengdu, Peoples R China. [Ju, Peijun] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhu, Qiuan] Hohai Univ, Coll Hydrol & Water Resources, Nanjing, Peoples R China. [Xu, Xingliang; Niu, Shuli; Zhang, Yangjian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China. [Gao, Yongheng; Feng, Xiaojuan] Chinese Acad Sci, Inst Bot, Beijing, Peoples R China. [Peng, Changhui] Hunan Normal Univ, Sch Geog Sci, Changsha, Peoples R China. [Peng, Changhui] Univ Quebec, Inst Environm Sci, Montreal, PQ, Canada. [Wang, Yanfen] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Wang, Yanfen] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing, Peoples R China. RP Chen, H (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Chengdu, Peoples R China.; Wang, YF (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China.; Wang, YF (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing, Peoples R China. EM chenhuai@cib.ac.cn; yfwang@ucas.ac.cn TC 3 Z9 3 PD OCT PY 2022 VL 3 IS 10 BP 701 EP 716 DI 10.1038/s43017-022-00344-2 EA SEP 2022 UT WOS:000860371500001 DA 2023-03-23 ER PT J AU Luo, QY Ma, YG Chen, Z Xie, HC Wang, YL Zhou, LY Ma, YS AF Luo, Qiaoyu Ma, Yonggui Chen, Zhi Xie, Huichun Wang, Yanlong Zhou, Lianyu Ma, Yushou TI Biochemical responses of hairgrass (Deschampsia caespitosa) to hydrological change SO FRONTIERS IN PLANT SCIENCE DT Article AB Plant growth and development are closely related to water availability. Water deficit and water excess are detrimental to plants, causing a series of damage to plant morphology, physiological and biochemical processes. In the long evolutionary process, plants have evolved an array of complex mechanisms to combat against stressful conditions. In the present study, the duration-dependent changes in ascorbate (AsA) and glutathione (GSH) contents and activities of enzymes involved in the AsA-GSH cycle in hairgrass (Deschampsia caespitosa) in response to water stress was investigated in a pot trial using a complete random block design. The treatments were as follows: (1) heavily waterlogging, (2) moderate waterlogging, (3) light waterlogging, (4) light drought, (5) moderate drought, (6) heavily drought, and (7) a control (CK) with plant be maintained at optimum water availability. The hairgrass plants were subjected to waterlogging or drought for 7, 14, 21 and 28 days and data were measured following treatment. Results revealed that hairgrass subjected to water stress can stimulate enzymatic activities of ascorbate peroxidase (APX), glutathione peroxidase (GPX), glutathione reductase (GR), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR) and L-galactono-1, 4-lactone dehydrogenase (GalLDH), switched on the ascorbate-glutathione (AsA-GSH) cycle and the L-galactose synthesis, up-regulated the contents of AsA and GSH, and maintained higher ratios of ascorbate to dehydroascorbate (AsA/DHA) and reduced glutathione to oxidized glutathione (GSH/GSSG) to alleviate potential oxidative damage. However, the light waterlogging did not induce hairgrass under stress to switch on the AsA-GSH pathway. In general, the critic substances and enzyme activities in AsA-GSH metabolic pathway increased as the increase of water stress intensity. As the increase of exposure duration, the critic antioxidant substances content and enzyme activities increased first and then maintained a relatively stable higher level. Our findings provide comprehensive information on biochemical responses of hairgrass to hydrological change, which would be a major step for accelerating ecological restoration of degradation alpine marshes in the Qinghai-Tibetan Plateau. C1 [Luo, Qiaoyu; Ma, Yonggui; Chen, Zhi; Xie, Huichun; Zhou, Lianyu] Qinghai Normal Univ, Sch Life Sci, Xining, Peoples R China. [Luo, Qiaoyu; Ma, Yonggui; Chen, Zhi; Xie, Huichun; Zhou, Lianyu] Qinghai Normal Univ, Qinghai Prov Key Lab Med Plant & Anim Resources Qi, Xining, Peoples R China. [Luo, Qiaoyu; Ma, Yonggui; Chen, Zhi; Xie, Huichun; Zhou, Lianyu] Qinghai Normal Univ, Acad Plateau Sci & Sustainabil, Xining, Peoples R China. [Luo, Qiaoyu; Wang, Yanlong; Ma, Yushou] Qinghai Univ, Coll Agr & Anim Husb, Xining, Peoples R China. RP Ma, YS (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining, Peoples R China. EM mayushou@sina.com TC 0 Z9 0 PD SEP 26 PY 2022 VL 13 AR 987845 DI 10.3389/fpls.2022.987845 UT WOS:000866462000001 DA 2023-03-23 ER PT J AU Chen, YY Yang, H Bao, GS Pang, XP Guo, ZG AF Chen, Ying Ying Yang, Huan Bao, Gen Sheng Pang, Xiao Pan Guo, Zheng Gang TI Effect of the presence of plateau pikas on the ecosystem services of alpine meadows SO BIOGEOSCIENCES DT Article AB The activity of small mammalian herbivores influences grassland ecosystem services in arid and semi-arid regions. Plateau pika (Ochotona curzoniae) was considered to be a focal organism to investigate the effect of small mammalian herbivores on meadow ecosystem services in alpine regions. In this study, a home-range scale was used to measure the forage available to livestock, water conservation, carbon sequestration and soil nutrient maintenance (total nitrogen, phosphorus and potassium) in the topsoil layer, and a quadrat scale was used to assess the biodiversity conservation of alpine meadows. This study showed that the forage available to livestock and water conservation was 19% and 16% lower in the presence of plateau pikas than in their absence, and biodiversity conservation, carbon sequestration, soil nitrogen and phosphorus maintenance was 15 %, 29 %, 10% and 8.9% higher in the presence of plateau pikas than in their absence. In contrast, it had no impact on soil potassium maintenance of meadow ecosystems in alpine regions. The forage available to livestock, biodiversity conservation and soil nutrient maintenance of meadow ecosystems in alpine regions had maximum values as the disturbance intensity of plateau pikas increased; the water conservation tended to decrease linearly with the increasing disturbance intensity of plateau pikas. These results present a pattern of plateau pikas influencing the ecosystem services of meadow ecosystems in alpine regions, enriching our understanding of the small mammalian herbivores in relation to grassland ecosystem service. C1 [Chen, Ying Ying; Yang, Huan; Pang, Xiao Pan; Guo, Zheng Gang] Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China. [Chen, Ying Ying; Yang, Huan; Pang, Xiao Pan; Guo, Zheng Gang] Lanzhou Univ, Engn Res Ctr Grassland Ind, Minist Educ, Lanzhou 730020, Peoples R China. [Chen, Ying Ying; Yang, Huan; Pang, Xiao Pan; Guo, Zheng Gang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. [Bao, Gen Sheng] Qinghai Univ, Acad Anim & Vet Sci, Qinghai Acad Anim & Vet Sci, Xining 810016, Peoples R China. RP Guo, ZG (通讯作者)，Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China.; Guo, ZG (通讯作者)，Lanzhou Univ, Engn Res Ctr Grassland Ind, Minist Educ, Lanzhou 730020, Peoples R China.; Guo, ZG (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. EM chenyy2019@lzu.edu.cn; guozhg@lzu.edu.cn TC 0 Z9 0 PD SEP 19 PY 2022 VL 19 IS 18 BP 4521 EP 4532 DI 10.5194/bg-19-4521-2022 UT WOS:000855019100001 DA 2023-03-23 ER PT J AU Liu, X Huang, XT Qin, WP Li, XA Ma, ZW Li, HX Li, LH Li, CZ AF Liu, Xiang Huang, Xiaotao Qin, Wenping Li, Xiaoan Ma, Zhiwen Li, Hongxian Li, Lanhai Li, Changzhong TI Effects of establishing cultivated grassland on soil organic carbon fractions in a degraded alpine meadow on the Tibetan Plateau SO PEERJ DT Article AB Background. The degradation of alpine meadows has induced substantial losses of soil organic carbon (SOC) on the Tibetan Plateau. A commonly-used method for rehabilitating degraded alpine meadows in this region is establishing cultivated grasslands through sowing seed mixtures, but its impact on the biochemical stability of SOC has remained inadequately explored. Methods. In this study, a total of 20 composited 0-20 cm soil samples were collected from a heavily degraded alpine meadow (DM) and three adjacent cultivated grasslands established for 3 years (CG3), 12 years (CG12), and 17 years (CG17) on the eastern Tibetan Plateau, and the SOC pool was separated into labile C pool I (LOC I), labile C pool II (LOC II), and recalcitrant C pool (ROC) in order to investigate changes in contents of SOC fractions that have different biochemical stabilities after the establishment of cultivated grassland. Results. Although the establishment of cultivated grasslands led to increases in soil total organic C content, the increase was only significant in samples with 17 years of cultivation. We found that the contents of the three SOC fractions were higher at CG3 and CG12 compared with those in the DM, and the differences were only significant for soil LOC II. By comparison, 17 years of cultivation led to significant increases in all of the SOC fraction contents. The results implied that different cultivation years had distinct impacts on SOC fractions in cultivated grasslands, and longer cultivation years contributed to accumulated soil ROC. The recalcitrance index of SOC in the DM was higher than that at CG3 and CG12, but lower than that at CG17. This was possibly due to the generally low litter quality of cultivated grasslands, which led to a slow release of complex compounds to soils. Moreover, it was observed that soil C:N ratio was a potential in dicator of SOC biochemical stability because of their close correlation. Conclusions. Our findings suggest that the long-term establishment of cultivated grasslands on DM is a promising solution to recovering both the quantity and stability of SOC on the Tibetan Plateau. C1 [Liu, Xiang; Qin, Wenping] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Huang, Xiaotao] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Reg Lab Qinghai, Xining, Peoples R China. [Huang, Xiaotao] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. [Qin, Wenping; Li, Xiaoan; Ma, Zhiwen; Li, Changzhong] Qinghai Univ, Coll Ecoenvironm Engn, Xining, Peoples R China. [Li, Hongxian] Chinese Acad Agr Sci, Inst Grassland Res, Hohhot, Peoples R China. [Li, Hongxian] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Xining, Peoples R China. [Li, Lanhai] Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi, Peoples R China. [Li, Lanhai] CAS Res Ctr Ecol & Environm Cent Asia, Urumqi, Peoples R China. RP Huang, XT (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Reg Lab Qinghai, Xining, Peoples R China.; Huang, XT (通讯作者)，Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China.; Li, CZ (通讯作者)，Qinghai Univ, Coll Ecoenvironm Engn, Xining, Peoples R China. EM xthuang@nwipb.cas.cn; lichangzhongqh@163.com TC 0 Z9 0 PD SEP 13 PY 2022 VL 10 AR e14012 DI 10.7717/peerj.140122/18 UT WOS:000879070500002 DA 2023-03-23 ER PT J AU Liu, YX Liu, SL Wang, FF Liu, H Li, MQ Sun, YX Wang, QB Yu, L AF Liu, Yixuan Liu, Shiliang Wang, Fangfang Liu, Hua Li, Mingqi Sun, Yongxiu Wang, Qingbo Yu, Lu TI Identification of key priority areas under different ecological restoration scenarios on the Qinghai-Tibet Plateau SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB With the intensification of climate warming and human activities, the ecosystems on the Qinghai-Tibet Plateau (QTP) are facing increasing threats which leads to extensive ecological degradation. Ecological restoration measures need to be implemented to improve biodiversity and ecosystem services to mitigate the impact of climate change and human disturbances. However, the key priority areas (KPAs) for ecological restoration are not clear on the QTP, and the benefits of ecosystem services for ecological restoration are often ignored. In this study, we are the first to identify the KPAs based on the quantitative evaluation method and multicriteria optimization algorithm under five restoration scenarios aiming at ecosystem service improvement on the QTP. Results showed that: (1) The benefits of ecological restoration for climate change mitigation and associated costs under different scenarios showed generally similar spatial variability, exhibiting higher in the south and lower in the west, which were different from those for biodiversity. (2) The restoration priorities in Sichuan and Yunnan were generally higher under scenarios II and V, while in Xinjiang, Sichuan, Yunnan, and western and southern Tibet were higher under scenarios I, III and IV. (3) For different ecosystems, the similarities lied in that the restoration priorities of wetland ecosystem were the highest, while those of desert ecosystem were the lowest under five restoration scenarios. (4) When the restoration area requirement was 25% of the total degraded area, the highest restoration priority levels under scenarios I, III and IV were mainly distributed in Guinan, Renbu, Nierong and Chayu counties, and under scenarios II and V were mainly distributed in Renbu, Lang and Guinan counties. When the restoration area requirements were 50% and 75% of the total degraded area, the counties with higher restoration priority levels under scenario II were different from those under other four scenarios. This study identified the KPAs under different restoration scenarios, which provided references for the restoration measures implementation on the QTP. C1 [Liu, Yixuan; Liu, Shiliang; Wang, Fangfang; Liu, Hua; Li, Mingqi; Sun, Yongxiu; Wang, Qingbo; Yu, Lu] Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. RP Liu, SL (通讯作者)，Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM shiliangliu@bnu.edu.cn TC 2 Z9 2 PD DEC 1 PY 2022 VL 323 AR 116174 DI 10.1016/j.jenvman.2022.116174 EA SEP 2022 UT WOS:000858366200001 DA 2023-03-23 ER PT J AU Cui, Z Liu, YF Liu, Y Leite, PAM Shi, JJ Shi, ZH Wu, GL AF Cui, Zeng Liu, Yi-Fan Liu, Yu Leite, Pedro A. M. Shi, Jianjun Shi, Zhi-Hua Wu, Gao-Lin TI Fragmentation alters the soil water conservation capacity of hillside alpine meadows on the Qinghai-Tibetan Plateau SO GEODERMA DT Article AB The Qinghai-Tibetan Plateau-known as the roof of the world and the water tower of Asia-is facing serious degradation of its ecosystems, with alpine meadows being particularly threatened. However, little is known about how the loss of mattic epipedon (the characteristic topsoil of alpine meadows) alters the water conservation capacity of the region. Here we examined the effects of different mattic epipedon coverages on surface runoff, evapotranspiration, and soil water storage under different rainfall conditions. Our results showed that the surface runoff was significantly higher under moderate rain conditions (P > 10 mm day(-1)) than under light rain conditions (P < 10 mm day(-1)), and that declining coverage significantly increased surface runoff, especially under moderate rain conditions. The average evapotranspiration at 90 %, 60 %, and 30 % mattic epipedon coverages were 5.38 mm, 5.88 mm, and 6.38 mm under non-rainfall conditions, and 0.97 mm, 1.60 mm, and 2.24 mm under moderate rain conditions. Meanwhile, mattic epipedon coverage had a positive effect on the supplementation of soil water under moderate rainfall and on the conservation of soil water under non-rainfall conditions. Overall, alpine meadows with higher mattic epipedon coverage were more effective at maintaining surface runoff and improving soil water conservation. These findings highlight the importance of conserving and restoring alpine meadows to improve the water security in the Qinghai-Tibetan Plateau and other downstream regions. C1 [Cui, Zeng; Liu, Yi-Fan; Liu, Yu; Shi, Zhi-Hua; Wu, Gao-Lin] Chinese Acad Sci, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, Minist Water Resource, Beijing 712100, Shaanxi, Peoples R China. [Cui, Zeng; Liu, Yi-Fan; Liu, Yu; Wu, Gao-Lin] Northwest A&F Univ, Inst Soil & Water Conservat, Xianyang 712100, Peoples R China. [Cui, Zeng; Liu, Yu; Wu, Gao-Lin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Leite, Pedro A. M.] Texas A&M Univ, Dept Ecol & Conservat Biol, College Stn, TX USA. [Shi, Jianjun; Wu, Gao-Lin] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Qinghai Prov Key Lab Adapt Management Alpine Grass, Xining 810016, Peoples R China. [Shi, Zhi-Hua; Wu, Gao-Lin] CAS Ctr Excellence Quaternary Sci & Global Change, Xian 710061, Peoples R China. RP Wu, GL (通讯作者)，Chinese Acad Sci, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, Minist Water Resource, Beijing 712100, Shaanxi, Peoples R China. EM wugaolin@nwsuaf.edu.cn TC 0 Z9 0 PD DEC 15 PY 2022 VL 428 AR 116133 DI 10.1016/j.geoderma.2022.116133 EA SEP 2022 UT WOS:000874918500005 DA 2023-03-23 ER PT J AU Zhang, CJ Kang, YK Yao, BH An, K Pu, QS Wang, ZC Sun, XM Su, JH AF Zhang, Caijun Kang, Yukun Yao, Baohui An, Kang Pu, Qiangsheng Wang, Zhicheng Sun, Xiaomei Su, Junhu TI Increased availability of preferred food and decreased foraging costs from degraded grasslands lead to rodent pests in the Qinghai-Tibet Plateau SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB The increased population density of rodent species during ongoing grassland degradation further deteriorates its conditions. Understanding the effects of grassland degradation on rodent feeding habits is of great value for optimizing grassland management strategies. In this study, lightly degraded (LD), moderately degraded (MD), severely degraded (SD), and reseeded grassland (RG) were selected and their plant resources and soil physical properties were investigated. In addition, the study used ITS2 barcode combined with the Illumina MiSeq sequencing method to analyze the food composition and proportion of plateau zokors in different grassland conditions. The results showed that, with grassland degradation, plant biomass decreased, but the relative proportion of forbs increased (LD: 32.05 +/- 3.89%; MD: 28.97 +/- 2.78%; SD: 49.16 +/- 4.67% and RG: 10.93 +/- 1.53%). Forbs were the main food of the plateau zokor, accounting for more than 90% of their diet, and the animal had a clear preference for Potentilla species; the soil compaction of feeding habits showed a decreasing trend in the 10-25 cm soil layer, suggesting a decreased foraging cost. Nutritional analysis showed that the stomach content of crude protein in zokors feeding on MD grassland was significantly higher than that of animals feeding on the other grassland types. Structural equation modeling showed that soil physical properties and the relative biomass of forbs had significant (P < 0.05) and extremely significant (P < 0.001) impacts on the population density of plateau zokors, with direct impact contribution rates of 0.20 and 0.63. As the severity of grassland degradation increased, although the aboveground and underground biomass of the plants decreased, the proportion of food preferred by the plateau zokor increased, and the corresponding changes in the feeding environment resulted in decreased foraging energy expenditure, thereby increasing the suitability of the degraded grassland for the plateau zokor. Compared with degraded grassland, the food diversity and evenness of zokors increased, the food niche width enlarged, and the proportion of weeds decreased in RG, which increased the difficulty of obtaining food. Reseeding in grassland management is therefore an effective way to control plateau zokors. C1 [Zhang, Caijun; Kang, Yukun; Yao, Baohui; An, Kang; Pu, Qiangsheng; Wang, Zhicheng; Su, Junhu] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou, Peoples R China. [Zhang, Caijun; Kang, Yukun; Yao, Baohui; An, Kang; Pu, Qiangsheng; Wang, Zhicheng; Sun, Xiaomei; Su, Junhu] Gansu Agr Univ, Massey Univ Res Ctr Grassland Biodivers, Lanzhou, Peoples R China. [Sun, Xiaomei] Gansu Agr Univ, Coll Resource & Environm Sci, Lanzhou, Peoples R China. RP Su, JH (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou, Peoples R China.; Su, JH (通讯作者)，Gansu Agr Univ, Massey Univ Res Ctr Grassland Biodivers, Lanzhou, Peoples R China. EM sujh@gsau.edu.cn TC 0 Z9 0 PD SEP 8 PY 2022 VL 10 AR 971429 DI 10.3389/fevo.2022.971429 UT WOS:000856751500001 DA 2023-03-23 ER PT J AU Wang, YF Lv, WW Xue, K Wang, SP Zhang, LR Hu, RH Zeng, H Xu, XL Li, YM Jiang, LL Hao, YB Du, JQ Sun, JP Dorji, T Piao, SL Wang, CH Luo, CY Zhang, ZH Chang, XF Zhang, MM Hu, YG Wu, TH Wang, JZ Li, BW Liu, PP Zhou, Y Wang, A Dong, SK Zhang, XZ Gao, QZ Zhou, HK Shen, MG Wilkes, A Miehe, G Zhao, XQ Niu, HS AF Wang, Yanfen Lv, Wangwang Xue, Kai Wang, Shiping Zhang, Lirong Hu, Ronghai Zeng, Hong Xu, Xingliang Li, Yaoming Jiang, Lili Hao, Yanbin Du, Jianqing Sun, Jianping Dorji, Tsechoe Piao, Shilong Wang, Changhui Luo, Caiyun Zhang, Zhenhua Chang, Xiaofeng Zhang, Mingming Hu, Yigang Wu, Tonghua Wang, Jinzhi Li, Bowen Liu, Peipei Zhou, Yang Wang, A. Dong, Shikui Zhang, Xianzhou Gao, Qingzhu Zhou, Huakun Shen, Miaogen Wilkes, Andreas Miehe, Georg Zhao, Xinquan Niu, Haishan TI Grassland changes and adaptive management on the Qinghai-Tibetan Plateau SO NATURE REVIEWS EARTH & ENVIRONMENT DT Review AB Climate change and anthropogenic activities are altering grasslands on the Qinghai-Tibetan Plateau. This Review examines vegetation and soil changes, and the role of various drivers in affecting them. Grasslands on the Qinghai-Tibetan Plateau (QTP) foster biodiversity, store carbon, maintain productivity and support pastoral livelihoods. These systems are being altered by climate change and anthropogenic activities, but the relative importance of these drivers are still debated. This Review examines QTP grassland changes since the 1980s and discusses the impacts of global change on plant communities and soil properties. The normalized difference vegetation index (NDVI) (which can be used to track vegetation greenness) has generally increased since the 1980s, but with substantial spatial variability and some local decreases. Rising temperatures were key in driving the NDVI increases, but also likely exacerbated water deficiency in areas with little precipitation (<100 mm year(-1)), accounting for some of the spatial variability in trends. Intense livestock grazing negatively affects vegetation and soil when stocking rates are higher than grassland carrying capacity, causing grassland degradation. Degraded grassland can be effectively restored by management policies that minimize or exclude grazing and by adaptive management; these practices became important drivers of net primary production increases after 2000. However, better management of grasslands under a future of increasing temperatures and settlement requires a deeper understanding of the large-scale plant species composition shifts and the combined effects of climate change and anthropogenic activities. C1 [Wang, Yanfen; Lv, Wangwang; Wang, Shiping; Zhang, Lirong; Jiang, Lili; Sun, Jianping; Dorji, Tsechoe; Piao, Shilong; Li, Bowen; Liu, Peipei; Zhou, Yang; Wang, A.] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing, Peoples R China. [Wang, Yanfen; Lv, Wangwang; Xue, Kai; Hu, Ronghai; Zeng, Hong; Du, Jianqing; Sun, Jianping; Li, Bowen; Liu, Peipei; Zhou, Yang; Wang, A.; Niu, Haishan] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Zhang, Lirong; Zhang, Xianzhou] Hebei Normal Univ Nationalities, Dept Resources & Environm, Chengde, Peoples R China. [Xu, Xingliang; Dong, Shikui] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing, Peoples R China. [Li, Yaoming] Beijing Forestry Univ, Coll Grassland Sci, Beijing, Peoples R China. [Hao, Yanbin] Univ Chinese Acad Sci, Coll Life Sci, Beijing, Peoples R China. [Wang, Changhui] Shanxi Agr Univ, Coll Grassland Sci, Taigu, Peoples R China. [Luo, Caiyun; Zhang, Zhenhua; Zhou, Huakun; Zhao, Xinquan] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. [Chang, Xiaofeng] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryl & Farming Loess Pl, Yangling, Shaanxi, Peoples R China. [Zhang, Mingming] Minist Agr & Rural Affairs, Biogas Inst, Team Strategy & Policy Rural Biomass Energy & Liv, Chengdu, Peoples R China. [Hu, Yigang; Wu, Tonghua] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, Lanzhou, Peoples R China. [Wang, Jinzhi] Chinese Acad Forestry, Wetland Inst, Beijing, Peoples R China. [Gao, Qingzhu] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. [Shen, Miaogen] Beijing Normal Univ, Fac GeographicalSci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing, Peoples R China. [Wilkes, Andreas] Values Dev Ltd, Bury St Edmunds, Suffolk, England. [Miehe, Georg] Philipps Univ Marburg, Fac Geog, Marburg, Germany. RP Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing, Peoples R China. EM wangsp@itpcas.ac.cn TC 8 Z9 8 PD OCT PY 2022 VL 3 IS 10 BP 668 EP 683 DI 10.1038/s43017-022-00330-8 EA SEP 2022 UT WOS:000850429300001 DA 2023-03-23 ER PT J AU Ning, J Liu, SS Kamran, M Sun, Y Xu, L Wang, H Zhang, ML Chang, SH West, CP Hou, FJ AF Ning, Jiao Liu, Shengsheng Kamran, Muhammad Sun, Yi Xu, Lei Wang, Hua Zhang, Minglei Chang, Shenghua West, Charles P. Hou, Fujiang TI Trace elements apportionment in forage, soil, and livestock in rangeland ecosystems along climatic gradients SO ENVIRONMENTAL RESEARCH DT Article AB Background: Alpine meadows, typical steppes, and deserts are among the globally important rangeland types that are generally distributed along temperature and precipitation gradients. Mineral losses caused by grazing are one of the key factors that can lead to instability or even degradation of these rangeland ecosystems.Methods: We examined the concentrations of Cu, Fe, Mn, and Zn in soil, forage, and livestock dungs from diverse rangeland types in northwest China, to determine the relationships between these trace elements (TEs) con-centrations and climatic factors (i.e., temperature, precipitation, and humidity), and to evaluate the potential risks of TEs deficiencies or excesses in these rangeland ecosystems.Results: Forage Zn concentrations in forage of all three types of rangeland, and Cu concentrations in forage of the alpine meadow did not meet the growth requirements of grazing livestock. Concentrations of Cu, Fe, and Mn in forage and Fe, Mn, and Zn in livestock dungs had quadratic parabola relationships with temperature, precipi-tation, and humidity, but the relationships between climate factors and Cu, Fe, and Mn concentrations in soil were not significant. In addition, the abilities of the plant to absorb Cu, Fe, and Zn from soil were stronger in the typical steppe than that in the alpine meadows and desert. Also, the abilities of livestock to return TEs to soil were stronger in the alpine meadow than that in the typical steppe and desert.Conclusion: We derived a conceptual mode that the ratio of TE concentrations of the plant to soil and of livestock dung to forage represents the abilities of plants to absorb TEs from the soil matrix and livestock to return TEs to soil or to absorb TEs from forage, respectively. Results indicate potentially more serious risks of TEs deficiencies, especially that of Zn than previously considered in typical steppes and desert rangelands. C1 [Ning, Jiao; Liu, Shengsheng; Kamran, Muhammad; Sun, Yi; Xu, Lei; Wang, Hua; Zhang, Minglei; Chang, Shenghua; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agro Eco Syst, Minist Lab, Lanzhou 730020, Gansu, Peoples R China. [West, Charles P.] Texas Tech Univ, Dept Plant & Soil Sci, Lubbock, TX 79409 USA. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agro Eco Syst, Minist Lab, Lanzhou 730020, Gansu, Peoples R China. EM cyhoufj@lzu.edu.cn TC 0 Z9 0 PD DEC PY 2022 VL 215 AR 114222 DI 10.1016/j.envres.2022.114222 EA SEP 2022 PN 1 UT WOS:000860482400002 DA 2023-03-23 ER PT J AU Zou, SB Qian, JK Xu, BR Tu, ZY Zhang, WY Ma, XL Liang, Y AF Zou, Songbing Qian, Jikun Xu, Baorong Tu, Zhenyu Zhang, Wenyong Ma, Xuanlong Liang, Yu TI Spatiotemporal changes of ecosystem health and their driving mechanisms in alpine regions on the northeastern Tibetan Plateau SO ECOLOGICAL INDICATORS DT Article AB Ecosystem health plays a vital role in the development of regional ecological environment. Gannan Plateau, an important water conservation area in the upper reaches of the Yellow River, is located at the northeastern margin of the Qinghai-Tibet Plateau. Due to the importance of the region, understanding the spatiotemporal patterns of the ecosystem health within this region is particularly critical. Previous studies on regional ecosystem health assessment mainly focused on single ecosystem type such as wetland, forest, and grassland, while there are relatively few studies that comprehensively assessed ecosystem health at high-spatial resolution in Gannan alpine areas. In this study, 11 counties and cities in Gannan Tibetan and Linxia Hui Autonomous Prefecture of the Gansu Province, China were used as the study area. We evaluated the ecosystem health of 154 township units from 2000 to 2020 with methods of Pressure-State-Response model (PSR) and Analytic Hierarchy Process (AHP), using a combination of satellite remote sensing data, social statistics data, meteorological data, and other geospatial data sources. The results showed that overall ecosystems in the southwestern part of the study area exhibited healthier condition than those located in the northeastern part, which is mainly due to the combination of the natural environment and the intensity of human activities in different regions. Over the past 20 years, due to the active implementation of relevant ecological protection and restoration policies by various regional governments and the improvement of the natural environment, the average ecosystem health status of Gannan Plateau has increased by 15.04 %, showing an improving trend in varying degrees or being stable, no declining trend was observed except for a small town. Our results implied that management should take different measures according to the differences of regional ecosystem health level, also pay more attention to areas where the ecosystem health status has not improved. C1 [Zou, Songbing; Qian, Jikun; Xu, Baorong; Tu, Zhenyu; Zhang, Wenyong; Ma, Xuanlong; Liang, Yu] Lanzhou Univ, Minist Educ, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Peoples R China. RP Qian, JK (通讯作者)，Lanzhou Univ, Minist Educ, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Peoples R China. EM qianjk20@lzu.edu.cn TC 0 Z9 0 PD OCT PY 2022 VL 143 AR 109396 DI 10.1016/j.ecolind.2022.109396 EA SEP 2022 UT WOS:000862267300006 DA 2023-03-23 ER PT J AU Liu, M Yu, CL Zhu, TB Xu, XL Wang, YF AF Liu, Min Yu, Chengling Zhu, Tongbin Xu, Xingliang Wang, Yanfen TI Restoration of degraded alpine grasslands alters plant-microbial competition for nitrogen SO BIOLOGY AND FERTILITY OF SOILS DT Article AB Plant-microbial interaction for nitrogen (N) is important in plant growth, soil fertility, and function of grasslands. However, it remains unclear how plant-microbial competition for N changes after the restoration of degraded alpine grasslands. This study aimed to explore the dynamics of plant-microbial competition for N in restoration chronosequences (i.e., short-, medium-, and long-term) in an alpine meadow and an alpine steppe on the Qinghai-Tibetan Plateau. Two inorganic forms of N (ammonium (NH4+ ) and nitrate (NO3-)) and one organic N (glycine) were used for the in situ N-15 labeling experiments. The competition between microorganisms and plants (i.e., ratios) for N increased by 4.8 times after medium- than short-term restoration in the alpine meadow and remained stable after each restoration. Compared to short-term restoration, medium-term restoration increased the N uptake of microorganisms by 2.4 times in alpine meadow and 4.3 times in alpine steppe. Microorganisms and plants showed chemical niche differentiation between NH4+ and NO3- uptake in both alpine ecosystems after medium-term restoration, with microorganisms taking up more NH4+ but plants taking up more NO3-. Competition between microorganisms and plants decreased after long-term compared with medium-term restoration, maintaining the microbial to plant N uptake ratio > 1. Long-term restoration increased plant N uptake in the alpine meadow, while decreased the microbial N uptake in the alpine steppe. Neither microorganisms nor plants showed a preference for glycine, but glycine uptake by microorganisms was higher than plants after medium- and long-term restorations. These findings provide valuable insights into the restoration of degraded alpine grasslands from the perspective of plant-microbial competition for available N in soil, which may be useful for developing sustainable grassland management practices. C1 [Liu, Min; Yu, Chengling; Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, 11A Datun Rd, Beijing 100101, Peoples R China. [Liu, Min; Yu, Chengling] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 101408, Peoples R China. [Zhu, Tongbin] Chinese Acad Geol Sci, Inst Karst Geol, Karst Dynam Lab, MLR & Guangxi, Guilin 541004, Peoples R China. [Wang, Yanfen] Univ Chinese Acad Sci, Coll Life Sci, Beijing 101408, Peoples R China. RP Xu, XL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, 11A Datun Rd, Beijing 100101, Peoples R China.; Wang, YF (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 101408, Peoples R China. EM xuxingl@hotmail.com; yfwang@ucas.ac.cn TC 1 Z9 1 PD OCT PY 2022 VL 58 IS 7 BP 803 EP 814 DI 10.1007/s00374-022-01660-x EA SEP 2022 UT WOS:000849472800002 DA 2023-03-23 ER PT J AU Abalori, TA Cao, WX Weobong, CAA Sam, FE Li, W Osei, R Wang, SL AF Abalori, Theophilus Atio Cao, Wenxia Weobong, Conrad Atogi-Akwoa Sam, Faisal Eudes Li, Wen Osei, Richard Wang, Shilin TI Effects of vegetation patchiness on ecosystem carbon and nitrogen storage in the alpine grassland of the Qilian Mountains SO FRONTIERS IN ENVIRONMENTAL SCIENCE DT Article AB Vegetation patchiness is common in degraded grasslands. Vegetation patchiness enhances the spatial variability of grassland soil organic carbon and total nitrogen. Stripped vegetation patches have a great impact on ecosystem carbon (C) and nitrogen (N) storage. Using field surveys, we examined the effects of patches on the ecosystem carbon and nitrogen storage of four typical alpine grass species patches (viz: Leymus secalinus, Koeleria pers, Stipa aliena, and Leontopodium nanum). The results indicated that ecosystem C, N, and respiration were significantly higher in intact vegetation patches than in stripped vegetation patches. Also, stripped vegetation patches recorded higher quantities of soil gravel content than the intact patches. In Leymus secalinus and Koeleria pers species patches, soil approximately contributed about 62% and vegetation about 38% to ecosystem carbon and nitrogen storage, whereas in Stipa aliena and Leontopodium nanum species patches, close to 80% of ecosystem carbon and nitrogen were found in the soil while close to 20% were stored in the vegetation. Soil total phosphorus (TP), total potassium (TK), available phosphorus (AP), soil microbial biomass carbon (MBC), and soil microbial biomass nitrogen (MBN) were higher in intact vegetation patches than in the stripped vegetation patches. Ecosystem carbon and nitrogen were observed to have a significant correlation with soil gravel content and vegetation productivity. Stripped vegetation patches resulted in decreased plant biomass input and an increased rate of soil erosion. We conclude that grassland patchiness resulted in the decline of ecosystem carbon and nitrogen storage due to a reduction in vegetation input and an increase in soil erosion. Grasslands are likely to have a higher possibility of serving as a C sink if the input of organic matter exceeds its output via sustainable management practices. C1 [Abalori, Theophilus Atio; Cao, Wenxia; Wang, Shilin] Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Grassland Ecosyst Key Lab, Minist Educ,Grassland Sci Coll, Lanzhou, Peoples R China. [Weobong, Conrad Atogi-Akwoa] Univ Dev Studies, Fac Nat Resources & Environm, Tamale, Ghana. [Sam, Faisal Eudes] Gansu Agr Univ, Coll Food Sci & Engn, Lanzhou, Peoples R China. [Li, Wen] Qinghai Univ, Qinghai Acad Anim Sci & Vet Med, Key Lab Dev Forage Germplasm Qinghai Tibetan Plate, Xining, Peoples R China. [Osei, Richard] Gansu Agr Univ, Coll Plant Protect, Lanzhou, Peoples R China. RP Cao, WX (通讯作者)，Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Grassland Ecosyst Key Lab, Minist Educ,Grassland Sci Coll, Lanzhou, Peoples R China. EM caowenxia@foxmail.com TC 0 Z9 0 PD SEP 1 PY 2022 VL 10 AR 879717 DI 10.3389/fenvs.2022.879717 UT WOS:000891286900001 DA 2023-03-23 ER PT J AU Brierley, G Li, XL Fryirs, K Gao, A Shi, Y Perry, GLW Cullum, C AF Brierley, Gary Li Xi-lai Fryirs, Kirstie Gao Jay Shi Yan Perry, George L. W. Cullum, Carola TI Degradation and recovery of alpine meadow catenas in the source zone of the Yellow River, Western China SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Process interactions on catenas have supported grazing adapted ecosystems and sustained biodiversity values in the source zone of the Yellow River in western China for millennia. In recent decades, anthropogenic disturbance and climate change have threatened the integrity of these systems, impacting upon environmental values and their capacity to sustain local livelihoods. Collaborations between local experts and a team of international researchers during a workshop and field excursion to this area in July 2019 developed a cross-disciplinary, process-based model of alpine meadow catenas. This paper relates the contemporary health of these grassland-wetland systems to their 'best achievable state' under prevailing boundary conditions, differentiating stages of degradation and recovery in relation to climate and land use changes. Recovery is underway for alpine meadow catenas at Maqin. Reduced land use pressures (stocking rates) and longer growing seasons have enhanced grassland-wetland conditions. However, recovery prospects are limited for local areas of extremely degraded grasslands (heitutan), as breached abiotic thresholds have resulted in soil and nutrient loss and reduced capacity for water retention. While lagomorphs and rodents act as ecosystem engineers when alpine meadows are in a healthy state, irruptions locally increase the proportion of bare ground and inhibit recovery potential. Management options that support recovery of alpine meadows are presented for differing stages of degradation. C1 [Brierley, Gary; Gao Jay; Shi Yan; Perry, George L. W.; Cullum, Carola] Univ Auckland, Sch Environm, Private Bag 92019, Auckland 1081, Aotearoa, New Zealand. [Li Xi-lai] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Fryirs, Kirstie] Macquarie Univ, Dept Earth & Environm Sci, N Ryde, NSW 2019, Australia. RP Brierley, G (通讯作者)，Univ Auckland, Sch Environm, Private Bag 92019, Auckland 1081, Aotearoa, New Zealand. EM g.brierley@auckland.ac.nz; xilai-li@163.com; kirstie.fryirs@mq.edu.au; jg.gao@auckland.ac.nz; yshi917@aucklanduni.ac.nz; george.perry@auckland.ac.nz; carolacullum@gmail.com TC 1 Z9 1 PD SEP PY 2022 VL 19 IS 9 BP 2487 EP 2505 DI 10.1007/s11629-021-7139-y UT WOS:000857902500003 DA 2023-03-23 ER PT J AU Liu, JF Lu, YQ AF Liu, Jiafeng Lu, Yaqiong TI How Well Do CMIP6 Models Simulate the Greening of the Tibetan Plateau? SO REMOTE SENSING DT Article AB The "warm-humid" climate change across the Tibetan Plateau (TP) has promoted grassland growth and an overall greening trend has been observed by remote sensing products. Many of the current generations of Earth System Models (ESMs) incorporate advanced process-based vegetation growth in the land surface module that can simulate vegetation growth, but the evaluation of their performance has not received much attention, especially over hot spots where projections of the future climate and vegetation growth are greatly needed. In this study, we compare the leaf area index (LAI) simulations of 35 ESMs that participated in CMIP6 to a remote-sensing-derived LAI product (GLASS LAI). The results show that about 40% of the models overestimated the Tibetan Plateau's greening, 48% of the models underestimated the greening, and 11% of the models showed a declining LAI trend. The CMIP6 models generally produced poor simulations of the spatial distribution of LAI trend, and overestimated the LAI trend of alpine vegetation, grassland, and forest, but underestimated meadow and shrub. Compared with other vegetation types, simulations of the forest LAI trend were the worst, the declining trend in forest pixels on the TP was generally underestimated, and the greening of the meadow was underestimated as well. However, the greening of the grassland, was greatly overestimated. For the Tibetan Plateau's averaged LAI, more than 70% of the models overestimated this during the growing seasons of 1981-2014. Similar to the forest LAI trend, the performance of the forest LAI simulation was the worst among the different vegetation types, and the forest LAI was underestimated as well. C1 [Liu, Jiafeng; Lu, Yaqiong] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610299, Peoples R China. [Liu, Jiafeng] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Lu, YQ (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610299, Peoples R China. EM yaqiong@imde.ac.cn TC 2 Z9 2 PD SEP PY 2022 VL 14 IS 18 AR 4633 DI 10.3390/rs14184633 UT WOS:000857632500001 DA 2023-03-23 ER PT J AU Yang, Y Wang, GX Lin, S Yang, Y Zhang, TZ Yu, H Lu, YQ Liu, BT Sun, JY AF Yang, Yi Wang, Genxu Lin, Shan Yang, Yan Zhang, Tongzuo Yu, Hui Lu, Yaqiong Liu, Bintao Sun, Juying TI How much aboveground net primary production can be used for human activities in the alpine grasslands in the Three Rivers Source Region (TRSR), China? SO ENVIRONMENTAL RESEARCH LETTERS DT Article AB Sustainable management of grasslands has always been an urgent issue for policy-makers. The three rivers source region (TRSR) contains widely distributed natural grasslands and is sensitive to climate warming. To enable the sustainable development of the human-nature system in the TRSR, we propose a novel indicator based on the allocation of aboveground net primary production (ANPP). The indicator we proposed is the ANPP that can be used for human activities (UANPP). In the study, we simulated the spatial and temporal patterns of the UANPP in the alpine grasslands in the TRSR during 1979-2016 and explored the main driving factors of the UANPP. The results revealed that (a) the annual total UANPP in the TRSR was 13.22 TgC, approximately accounting for 47% of total ANPP. (b) The areas with negative UANPP values accounted for 16% of the entire TRSR, and they were primarily located within the Nature Reserve of the Yangtze and Yellow river source regions, while three-quarters of the area exhibited improvement trends. (c) The regional mean UANPP significantly increased during 1979-2016, at a rate of 0.28 gC m(-2) yr(-1) (p < 0.01). In the entire TRSR, 87% of the area exhibited increasing trends. (d) The UANPP in most areas of the TRSR was strongly correlated with precipitation, and the effect of human activities on the UANNP increased slightly during the 38 year study period. The UANPP represents the upper limit of human use of nature. These findings provide a reference for policy-makers to make decisions toward human-nature system sustainability while meeting human needs for grassland resources. ANPP allocation between nature and human system is a potentially important tool from the standpoint of sustainable development. C1 [Yang, Yi; Yang, Yan; Yu, Hui; Lu, Yaqiong; Liu, Bintao] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Wang, Genxu; Lin, Shan; Sun, Juying] Sichuan Univ, Coll Water Resource & Hydropower, State Key Lab Hydraul & Mt River Engn, Chengdu 610065, Peoples R China. [Zhang, Tongzuo] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. [Yang, Yi] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Wang, GX (通讯作者)，Sichuan Univ, Coll Water Resource & Hydropower, State Key Lab Hydraul & Mt River Engn, Chengdu 610065, Peoples R China. EM wanggx@scu.edu.cn TC 0 Z9 0 PD SEP 1 PY 2022 VL 17 IS 9 AR 094047 DI 10.1088/1748-9326/ac8ec3 UT WOS:000853751700001 DA 2023-03-23 ER PT J AU Xia, ZX Huang, LC Fan, CY Jia, SC Lin, ZJ Liu, L Luo, J Niu, FJ Zhang, TJ AF Xia, Zhuoxuan Huang, Lingcao Fan, Chengyan Jia, Shichao Lin, Zhanjun Liu, Lin Luo, Jing Niu, Fujun Zhang, Tingjun TI Retrogressive thaw slumps along the Qinghai-Tibet Engineering Corridor: a comprehensive inventory and their distribution characteristics SO EARTH SYSTEM SCIENCE DATA DT Article; Data Paper AB The important Qinghai-Tibet Engineering Corridor (QTEC) covers the part of the Highway and Railway underlain by permafrost. The permafrost on the QTEC is sensitive to climate warming and human disturbance and suffers accelerating degradation. Retrogressive thaw slumps (RTSs) are slope failures due to the thawing of ice-rich permafrost. They typically retreat and expand at high rates, damaging infrastructure, and releasing carbon preserved in frozen ground. Along the critical and essential corridor, RTSs are commonly distributed but remain poorly investigated. To compile the first comprehensive inventory of RTSs, this study uses an iteratively semi-automatic method built on deep learning to delineate thaw slumps in the 2019 PlanetScope CubeSat images over a similar to 54 000 km(2) corridor area. The method effectively assesses every image pixel using DeepLabv3 C with limited training samples and manually inspects the deep-learningidentified thaw slumps based on their geomorphic features and temporal changes. The inventory includes 875 RTSs, of which 474 are clustered in the Beiluhe region, and 38 are near roads or railway lines. The dataset is available at https://doi.org/10.5281/zenodo.6397029 (Xia et al., 2021a), with the Chinese version at DOI: https://doi.org/10.11888/Cryos.tpdc.272672 (Xia et al. 2021b). These RTSs tend to be located on north-facing slopes with gradients of 1.2-18.1(o) and distributed at medium elevations ranging from 4511 to 5212ma.s.l. They prefer to develop on land receiving relatively low annual solar radiation (from 2900 to 3200 kWhm(-2)), alpine meadow covered, and loam underlay. Our results provide a significant and fundamental benchmark dataset for quantifying thaw slump changes in this vulnerable region undergoing strong climatic warming and extensive human activities. C1 [Xia, Zhuoxuan; Huang, Lingcao; Liu, Lin] Chinese Univ Hong Kong, Earth Syst Sci Programme, Fac Sci, Hong Kong, Peoples R China. [Fan, Chengyan; Jia, Shichao; Zhang, Tingjun] Lanzhou Univ, Coll Earth & Environm Sci, Key Lab West Chinas Environm DOE, Lanzhou, Peoples R China. [Lin, Zhanjun; Luo, Jing; Niu, Fujun] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou, Peoples R China. [Huang, Lingcao] Univ Colorado, Cooperat Inst Res Environm Sci, Earth Sci & Observat Ctr, Boulder, CO 80309 USA. RP Huang, LC (通讯作者)，Chinese Univ Hong Kong, Earth Syst Sci Programme, Fac Sci, Hong Kong, Peoples R China. EM huanglingcao@link.cuhk.edu.hk TC 2 Z9 2 PD AUG 31 PY 2022 VL 14 IS 9 BP 3875 EP 3887 DI 10.5194/essd-14-3875-2022 UT WOS:000847717200001 DA 2023-03-23 ER PT J AU Jize, Z Zhuoga, D Xiaoqing, Z Na, T Jiacuo, G Cuicheng, L Bandan, P AF Jize, Zhang Zhuoga, Deqing Xiaoqing, Zhang Na, Ta Jiacuo, Gesang Cuicheng, Luosang Bandan, Pingcuo TI Different feeding strategies can affect growth performance and rumen functions in Gangba sheep as revealed by integrated transcriptome and microbiome analyses SO FRONTIERS IN MICROBIOLOGY DT Article AB Due to the harsh environment in the Tibetan Plateau, traditional grazing greatly limits the growth potential of local animals and causes severe ecosystem degradation. This is an urgent issue to be solved, which requires alternative strategies for grazing animals in the Tibetan alpine pastoral livestock systems. This study aimed to investigate the effects of different feeding strategies on growth performance and ruminal microbiota-host interactions in the local breed of sheep (Gangba sheep). Thirty 9-month old Gangba sheep (n = 10 per group) were assigned to natural grazing (G), semi-grazing with supplementation (T), and barn feeding (F) groups (supplementation of concentrate and oat hay) based on body weight. At the end of the experiment (75 d), all sheep were weighed, rumen fluid was obtained from six sheep per group, and ruminal epithelium was obtained from 3 sheep per group. The results showed that: (1) Compared with the G and T groups, the F group significantly increased dry matter intake, average daily gain, and feed conversion ratio of animals. Additionally, Gangba sheep in the F group had higher concentrations of ruminal short-chain volatile fatty acids (VFAs), especially propionate and butyrate (P <0.05) than sheep in the G and T groups. (2) The principal coordinates analysis indicated a significant difference in bacterial composition among different feed strategies. More specifically, the relative abundance of propionate (unidentified F082 and Succiniclasticum) and butyrate-producing (Eubacterium_coprostanoligenes_group) genera were also observed to be increased in the F group, in which unidentified F082 was identified as a differential biomarker among the three groups according to linear discriminant analysis effect size analysis. (3) The dynamics of the rumen epithelial transcriptome revealed that ECM-receptor interactions, focal adhesion, and PI3K-Akt signaling pathways, which are critical in mediating many aspects of cellular functions such as cell proliferation and motility, were upregulated in the F group. In conclusion, under harsh conditions in the Tibetan alpine meadow, barn feeding increased ruminal VFAs concentrations (especially propionate and butyrate), which stimulated gene expression related to cell proliferation in rumen epithelium, appearing to be superior to natural grazing and semi-grazing in gaining body weight of the local Gangba sheep. C1 [Jize, Zhang; Xiaoqing, Zhang; Na, Ta] Chinese Acad Agr Sci, Inst Grassland Res, Hohhot, Peoples R China. [Zhuoga, Deqing; Jiacuo, Gesang; Cuicheng, Luosang; Bandan, Pingcuo] Tibet Acad Agr & Anim Husb Sci, Inst Livestock Res, Lhasa, Peoples R China. RP Xiaoqing, Z (通讯作者)，Chinese Acad Agr Sci, Inst Grassland Res, Hohhot, Peoples R China. EM zhangxiaoqing@caas.cn TC 1 Z9 1 PD AUG 24 PY 2022 VL 13 AR 908326 DI 10.3389/fmicb.2022.908326 UT WOS:000850734300001 DA 2023-03-23 ER PT J AU Deng, YH Li, XY Shi, FZ Chai, LN Zhao, SJ Ding, MK Liao, QW AF Deng, Yuanhong Li, Xiaoyan Shi, Fangzhong Chai, Linna Zhao, Shaojie Ding, Mengkai Liao, Qiwen TI Nonlinear effects of thermokarst lakes on peripheral vegetation greenness across the Qinghai-Tibet Plateau using stable isotopes and satellite detection SO REMOTE SENSING OF ENVIRONMENT DT Article AB Thermokarst lakes (TLs) widespread in thawing permafrost can degrade vegetation through thermomechanical erosion and waterlogging. However, whether TLs change water sources and alleviate water stress for plants is unknown, and previous knowledge about regional TL effects on surrounding vegetation greenness is rare. Here, we synthesized field investigations, stable isotopes, and remote sensing images from an unmanned aerial vehicle and Sentinel-2 to determine the effects of over 160,000 TLs on their surrounding growing-season normalized difference vegetation index (NDVI) in the Qinghai-Tibet Plateau. The results are as follows: 1) With the largest water source shifting from 0 to 10 cm soil water to lake water, TL-affected plants can grow better than TL-unaffected plants, which is associated with soil texture and the development stage of the lake. 2) Overall, the median affecting distances of TLs on surrounding surface moisture (tasseled cap wetness, TCW) and NDVI were 50 m with their 25th-75th percentiles of 40-70 m and 40-60 m, respectively; compared with the unaffected areas, TLs increased peripheral TCW but reduced NDVI with their median change rates of 19.84% and -10.42%, respectively. 3) However, the nonlinear response of NDVI to the TCW gradient was dominant, which was featured by a local peak NDVI due to the coexistence of the physical destruction and improved water availability, and both TCW and NDVI at the peak area were explicitly larger than those at the unaffected area. 4) Along southeast-northwest environmental gradients (topographic, climatic, and edaphic factors), the affected range and degradation ratio of NDVI were greater under drier climate, larger lake area, sand-richer soil, fewer soil nutrients, and worse vegetation type (e.g., alpine desert). Briefly, the net adverse consequence on NDVI suggests that TLs primarily represent permafrost-supported ecosystems deteriorating, but the clear nonlinear effects advance the knowledge of this landscape; additionally, these local vegetation changes can help interpret the regional greening/browning and promote the research on the biogeochemical interaction among TL, soil, and plants under climate warming and permafrost thawing. C1 [Deng, Yuanhong; Li, Xiaoyan; Shi, Fangzhong; Chai, Linna; Zhao, Shaojie; Ding, Mengkai; Liao, Qiwen] Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Deng, Yuanhong; Li, Xiaoyan; Shi, Fangzhong; Chai, Linna; Ding, Mengkai; Liao, Qiwen] Beijing Normal Univ, Fac Geog Sci, Sch Nat Resources, Beijing 100875, Peoples R China. [Li, Xiaoyan] Qinghai Normal Univ, Key Lab Tibetan Plateau Land Surface Proc & Ecol C, Minist Educ, Xining 810016, Peoples R China. [Li, Xiaoyan] Qinghai Normal Univ, Acad Plateau Sci & Sustainabil, Xining 810016, Peoples R China. RP Li, XY (通讯作者)，Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. EM xyli@bnu.edu.cn TC 0 Z9 0 PD OCT PY 2022 VL 280 AR 113215 DI 10.1016/j.rse.2022.113215 EA AUG 2022 UT WOS:000844040200002 DA 2023-03-23 ER PT J AU Yang, A Kang, XM Li, Y Zhang, XD Zhang, KR Kang, EZ Yan, ZQ Li, M Wang, XD Niu, YC Yan, L AF Yang, Ao Kang, Xiaoming Li, Yong Zhang, Xiaodong Zhang, Kerou Kang, Enze Yan, Zhongqing Li, Meng Wang, Xiaodong Niu, Yuechuan Yan, Liang TI Alpine wetland degradation reduces carbon sequestration in the Zoige Plateau, China SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Alpine wetland plays an important role in the global carbon balance but are experiencing severe degradation under climate change and human activities. With the aim to clarify the effect of alpine wetland degradation on carbon fluxes (including net ecosystem CO2 exchange, NEE; ecosystem respiration, ER; gross ecosystem productivity, GEP, and CH4 flux), we investigated 12 sites and measured carbon fluxes using the static chamber method in the Zoige alpine wetland during August 2018, including undegraded wetland (UD), lightly degraded wetland (LD), moderately degraded wetland (MD), and severely degraded wetland (SD). The results showed that carbon sink strengths differ among the Zoige wetlands with different degradation stages during the growing season. From UD to LD, the rate of carbon sequestration (mean value of NEE) increased by 25.70%; however, from LD to SD, it decreased by 81.67%. Wetland degradation significantly reduced soil water content (SWC), soil organic carbon (SOC), microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN). NEE was significantly correlated with MBC and MBN, while ER was positively correlated with ST but negatively correlated with SOC (P < 0.01). Among all measured environmental factors, GEP was positively correlated with pH (P < 0.01), while CH4 flux was most closely correlated with SOC, SWC, MBC, MBN, and ST (P < 0.001), and was also affected by pH and NO3- content (P < 0.01). These results suggest that the capacity of carbon sequestration in the Zoige wetlands reduced with intensification of the degradation. This study provides a reference for sustainably managing and utilizing degraded wetlands under climate change. C1 [Yang, Ao; Kang, Xiaoming; Li, Yong; Zhang, Xiaodong; Zhang, Kerou; Yan, Zhongqing; Li, Meng; Wang, Xiaodong; Yan, Liang] Chinese Acad Forestry, Inst Ecol Conservat & Restorat, Wetland Res Ctr, Beijing, Peoples R China. [Yang, Ao; Kang, Xiaoming; Li, Yong; Zhang, Xiaodong; Zhang, Kerou; Yan, Zhongqing; Li, Meng; Wang, Xiaodong; Yan, Liang] Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China. [Yang, Ao; Kang, Xiaoming; Li, Yong; Zhang, Xiaodong; Zhang, Kerou; Yan, Zhongqing; Li, Meng; Wang, Xiaodong; Yan, Liang] Sichuan Zoige Wetland Ecosyst Res Stn, Aba, Sichuan, Peoples R China. [Kang, Enze] Univ Chinese Acad Sci, Beijing, Peoples R China. [Kang, Enze] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. [Niu, Yuechuan] Univ Chinese Acad Sci, Coll Life Sci, Beijing, Peoples R China. RP Yan, L (通讯作者)，Chinese Acad Forestry, Inst Ecol Conservat & Restorat, Wetland Res Ctr, Beijing, Peoples R China.; Yan, L (通讯作者)，Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China.; Yan, L (通讯作者)，Sichuan Zoige Wetland Ecosyst Res Stn, Aba, Sichuan, Peoples R China. EM yanliang@caf.ac.cn TC 0 Z9 0 PD AUG 16 PY 2022 VL 10 AR 980441 DI 10.3389/fevo.2022.980441 UT WOS:000847327700001 DA 2023-03-23 ER PT J AU Duan, C Shi, PL Zong, N Zhang, XZ Yu, CQ AF Duan, Cheng Shi, Peili Zong, Ning Zhang, Xianzhou Yu, Chengqun TI Assessing Rangeland Sensitivity to Degradation in North Tibet SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB Rangelands are the dominant ecosystems in the Tibetan Plateau and the most critical livestock production resources. However, a large quantity of rangelands has degraded in North Tibet, with declined forage yield and invaded unpalatable weeds. Thus, identifying potential degradation is essential to manage rangelands sustainably in the future. In this study, we aimed to use an environmentally sensitive area index (ESAI) that integrated the conditions of vegetation, soil, climate, and management to assess rangeland degradation in North Tibet and identify the major drivers of degradation by the random forest model. The ESAI contained 16 indicators of the selected four categories, which were input by layers from geographic information system data. The results revealed that 33% of the study area was susceptive to rangeland degradation, in which alpine desert-steppes in the west, with the highest mean ESAI scores of 1.38, were the most sensitive areas. According to the degrees of degradation, only 9% of rangelands in the east had low mean values of ESAI (< 1.22), which were mostly located in the alpine meadow. The importance ranking for rangeland degradation based on the random forest model indicated that the highest importance was vegetation cover type, followed by grazing intensity and aridity with more than 60% mean decrease accuracy. Besides, field measurements showed that the adjusted correlation coefficient of multiple regression of four vegetation degradation indicators was 0.86, illustrating that the assessment as a proxy for rangeland degradation sensitivity is feasible. This study provides an important approach to evaluating potential rangeland degradation. Therefore, the assessment model is recommended for regional-level decision makers to manage rangeland degradation with full consideration of local physical conditions. (C) 2022 The Society for Range Management. Published by Elsevier Inc. All rights reserved. C1 [Duan, Cheng; Shi, Peili; Zong, Ning; Zhang, Xianzhou; Yu, Chengqun] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Duan, Cheng; Shi, Peili; Zhang, Xianzhou] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. EM shipl@igsnrr.ac.cn TC 2 Z9 2 PD SEP PY 2022 VL 84 IS 1 BP 86 EP 97 DI 10.1016/j.rama.2022.07.001 EA AUG 2022 UT WOS:000860454200009 DA 2023-03-23 ER PT J AU Li, CY Li, XL Yang, YW Shi, Y Li, HL AF Li, Chengyi Li, Xilai Yang, Yuanwu Shi, Yan Li, Honglin TI Degradation reduces the diversity of nitrogen-fixing bacteria in the alpine wetland on the Qinghai-Tibet Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB Biological nitrogen fixation is a key process in the nitrogen cycle and the main source of soil available nitrogen. The number and diversity of nitrogen-fixing bacteria directly reflect the efficiency of soil nitrogen fixation. The alpine wetland on the Qinghai-Tibet Plateau (QTP) is degrading increasingly, with a succession toward alpine meadows. Significant changes in soil physicochemical properties accompany this process. However, it is unclear how does the soil nitrogen-fixing bacteria change during the degradation processes, and what is the relationship between these changes and soil physicochemical properties. In this study, the nifH gene was used as a molecular marker to further investigate the diversity of nitrogen-fixing bacteria at different stages of degradation (none, light, and severe degeneration) in the alpine wetland. The results showed that wetland degradation significantly reduced the diversity, altered the community composition of nitrogen-fixing bacteria, decreased the relative abundance of Proteobacteria, and increased the relative abundance of Actinobacteria. In addition to the dominant phylum, the class, order, family, and genus of nitrogen-fixing bacteria had significant changes in relative abundance. Analysis of Mantel test showed that most soil factors (such as pH, soil water content (SWC), the organic carbon (TOC), total nitrogen (TN), and soil C:P ratio) and abundance had a significant positive correlation. TOC, TN, total phosphorus (TP), soil C:P ratio and Shannon had a significant positive correlation with each other. The RDA ranking further revealed that TOC, SWC, and TN were the main environmental factors influencing the community composition of nitrogen-fixing bacteria. It is found that the degradation of the alpine wetland inhibited the growth of nitrogen-fixing bacteria to a certain extent, leading to the decline of their nitrogen-fixing function. C1 [Li, Chengyi; Li, Xilai; Yang, Yuanwu] Qinghai Univ, Coll Agr & Anim Husb, Xining, Peoples R China. [Li, Xilai; Li, Honglin] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Shi, Yan] Univ Auckland, Sch Environm, Auckland, New Zealand. RP Li, XL (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining, Peoples R China.; Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. EM xilai-li@163.com TC 2 Z9 2 PD AUG 4 PY 2022 VL 13 AR 939762 DI 10.3389/fpls.2022.939762 UT WOS:000843547900001 DA 2023-03-23 ER PT J AU Ma, F Peng, PH AF Ma, Fei Peng, Pei-hao TI Spatial-temporal dynamics of alpine grassland coverage and its response to climate warming in Mt. Qomolangma Nature Preserve during 2000-2019 SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB The Qinghai-Tibet Plateau (QTP) has the largest and highest alpine grassland ecosystem in the world, which is considered to be the most sensitive and vulnerable ecosystem to climate change. Its dynamic changes and driving mechanism have always been widely researched. The Qomolangma National Nature Preserve (QNNP), with the largest altitude difference in the world, was selected as the study area to analyse the spatial-temporal dynamics of grassland coverage and the different characteristics of elevation gradients at the southern slope (SS) and northern slope (NS) with MODIS MOD13Q1 NDVI and MOD11A2 land surface temperature data from 2000 to 2019 using the Mann-Kendall trend test and Theil-Sen slope methods. Further, the response mechanism of grassland coverage to climate warming is discussed. The results revealed that from 2000 to 2019, the grassland coverage change in the study area is mainly stable. The increased area proportion of grassland coverage on the southern slope is significantly higher than that on the northern slope, and the decreased area proportion of grassland coverage on the northern slope is significantly greater than that on the southern slope. The change characteristics of grassland coverage in the QNNP exhibit an obvious elevation gradient; the higher the elevation, the greater the increased area proportion of grassland coverage, particularly on the SS. The land surface temperature can be used as a proxy for analysing the temporal and spatial variation trends of air temperature in the QNNP. With the increase of the altitude, the land surface temperature rise rate on both the southern slope and northern slope exhibited an increasing trend, and the sensitivity of grassland coverage to temperature rise was higher on the northern slope. The water condition was the decisive factor for the horizontal and vertical spatial heterogeneity of the dynamic change of grassland coverage, and the melting of glaciers and thawing of permafrost were important sources of water for grassland growth in the QNNP. Climate warming promotes the growth of grassland in areas with a sufficient water supply, but adversely affects the growth of grassland in areas with insufficient water supplies, which will be further intensified by human activities. C1 [Ma, Fei; Peng, Pei-hao] Chengdu Univ Technol, Coll Earth Sci, Chengdu 610059, Peoples R China. RP Peng, PH (通讯作者)，Chengdu Univ Technol, Coll Earth Sci, Chengdu 610059, Peoples R China. EM mafei0701@163.com; peihaop@163.com TC 0 Z9 0 PD AUG PY 2022 VL 19 IS 8 BP 2297 EP 2311 DI 10.1007/s11629-021-7110-y EA AUG 2022 UT WOS:000836131300002 DA 2023-03-23 ER PT J AU Ma, KK Xu, CL Yu, XJ Liu, YY Yang, H Wei, KT Jing, YY Jiang, JC Wang, H AF Ma, Kaikai Xu, Changlin Yu, Xiaojun Liu, Yuanyuan Yang, Hang Wei, Kongtao Jing, Yuanyuan Jiang, Jiachang Wang, Hui TI Rest grazing start from the critical period of soil thawing optimizes plant community characteristics and grassland grazing capacity in alpine meadows SO ECOLOGICAL ENGINEERING DT Article AB The grazing management of alpine meadows is very important for grassland health. In order to explore the optimal rest grazing period in cold season pasture of alpine meadows of the Qinghai-Tibet Plateau (QTP), the critical period of soil thawing-grass withering period (RP1), the later period of soil thawing-grass withering period (RP2), the initial period of grass regreening-grass withering period (RP3), the later period of grass regreening-grass withering period (RP4) and local traditional rest grazing (dominant plant height 5 cm-grass withering period) (RP5) was set in the Tianzhu alpine meadow on the eastern edge of the QTP. RP1 improved Gramineae and Cyperaceae coverage 140% and 37.80%, respectively, Cyperaceae aboveground biomass 58.52%, the total aboveground biomass 22.86%, and poisonous plants aboveground biomass was lower 29.39% than that in RP3. The Richness index and Shannon-Wiener index for the RP1 plant community were 12.12-24.72% and 2.46-19.75% higher than those in other rest grazing periods, respectively. The Simpson diversity index was 1.10% higher in RP1 than that in RP3, and the Pielou evenness index was 3.30% higher in RP1 than that in RP5. The neutral detergent fiber and acid detergent fiber contents of the plant increased with advanced rest grazing periods, being the highest in RP2. Crude protein, crude fat, and crude ash contents were the highest in RP5. The amount and digestible protein grazing capacities in RP1 were higher by 1.67-4.49 and 3.61-8.36 sheep units.ha(-1), respectively, than those in other rest grazing periods. RP1 rest grazing optimized the plant community structure, improved grassland productivity and plant community diversity, with a more stable plant community structure and higher grazing capacity. Therefore, the cold season pastures should be managed with a rest grazing in RP1 for the sustainable utilization of grassland ecosystem. C1 [Ma, Kaikai; Xu, Changlin; Yu, Xiaojun; Liu, Yuanyuan; Yang, Hang; Wei, Kongtao; Jing, Yuanyuan] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst,Pratacultural Engn Lab, Minist Educ Sino,US Ctr Grazing Land Ecosyst Sust, Lanzhou 730070, Peoples R China. [Jiang, Jiachang; Wang, Hui] Grassland Tech Extens Stn Gansu Prov, Lanzhou 730070, Gansu, Peoples R China. RP Yu, XJ (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst,Pratacultural Engn Lab, Minist Educ Sino,US Ctr Grazing Land Ecosyst Sust, Lanzhou 730070, Peoples R China. EM yuxj@gsau.edu.cn TC 0 Z9 0 PD OCT PY 2022 VL 183 AR 106763 DI 10.1016/j.ecoleng.2022.106763 EA AUG 2022 UT WOS:000877297500007 DA 2023-03-23 ER PT J AU Wang, HW Jin, HJ Li, XY He, RX Serban, RD Jin, XY Yang, X Serban, M Yang, SQ Wang, WH AF Wang, Hongwei Jin, Huijun Li, Xiaoying He, Ruixia Serban, Raul-D. Jin, Xiaoying Yang, Xue Serban, Mihaela Yang, Suiqiao Wang, Wenhui TI Land use and cover change in Northeast China and its impacts on the Xing'an permafrost in 1980s-2010s SO LAND DEGRADATION & DEVELOPMENT DT Article AB Boreal forest and wetland have important influences on the development and protection of the ecosystem-dominated Xing'an permafrost. However, the responses of different ecosystems to climate change and the impacts on the underlying permafrost are still unclear. Here, based on the multi-period land use/land cover (LULC) data and long-time series of air temperature, combined with the ordinary least squares (OLS) and ordinary kriging (OK) methods, the effects of land use and cover change (LUCC) on the distribution of mean annual air temperature (MAAT) and permafrost in Northeast China were analyzed. From 1980s to 2010s, MAAT showed an upward trend (0.025 degrees C per yr) and extents of permafrost showed a decreasing trend (-3668 km(2)yr(-1)) in Northeast China. Permafrost degradation mainly occurred in forested land and grassland, with areal reductions of 4.0106 x 10(4) and 3.8754 x 10(4) km(2), respectively. The transformation of LULC aggravates the degradation of permafrost. The conversions of forested land and grassland to cultivated land and forested land to grassland resulted in the shrinkage of permafrost extent by 6233 km(2) from 1980s to 2010s . Our results confirm the significant impacts of LUCC on the Xing'an permafrost resulting in its degradation. Additionally, they can provide a scientific basis for ecological environment protection and restoration and sustainable development of boreal forest and wetland ecosystems in permafrost regions of Northeast China. C1 [Wang, Hongwei; He, Ruixia] Chinese Acad Sci, Northwest Inst Eco Environm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou, Peoples R China. [Wang, Hongwei; Jin, Huijun; Li, Xiaoying; Jin, Xiaoying; Yang, Xue; Yang, Suiqiao; Wang, Wenhui] Northeast Forestry Univ, Sch Civil Engn, Inst Cold Reg Sci & Engn, Harbin, Peoples R China. [Wang, Hongwei; Jin, Huijun; Li, Xiaoying; Jin, Xiaoying; Yang, Xue; Yang, Suiqiao; Wang, Wenhui] Northeast Forestry Univ, Minist Educ Observ, Observat & Res Stn Permafrost Geo Environm Northe, Harbin, Peoples R China. [Jin, Huijun; Li, Xiaoying] Northeast Forestry Univ, Sch Forestry, Key Lab Sustainable Forest Ecosyst Management, Minist Educ, Harbin, Peoples R China. [Serban, Raul-D.] Eurac Res, Inst Alpine Environm, Bozen Bolzano, Italy. [Serban, Mihaela] West Univ Timisoara, Dept Geog, Appl Geomorphol & Interdisciplinary Res Ctr, Timis, Romania. RP Jin, HJ (通讯作者)，Northeast Forestry Univ, Sch Civil Engn, Harbin 150040, Peoples R China.; Li, XY (通讯作者)，Northeast Forestry Univ, Sch Forestry, Harbin 150040, Peoples R China. EM hjjin@nefu.edu.cn; lixiaoying@nefu.edu.cn TC 0 Z9 0 PD OCT PY 2022 VL 33 IS 16 BP 3133 EP 3149 DI 10.1002/ldr.4377 EA AUG 2022 UT WOS:000836003900001 DA 2023-03-23 ER PT J AU Wei, YQ Wang, WW Tang, XJ Li, H Hu, HW Wang, XF AF Wei, Yanqiang Wang, Wenwen Tang, Xuejie Li, Hui Hu, Huawei Wang, Xufeng TI Classification of Alpine Grasslands in Cold and High Altitudes Based on Multispectral Landsat-8 Images: A Case Study in Sanjiangyuan National Park, China SO REMOTE SENSING DT Article AB Land-use-cover change (LUCC)/vegetation cover plays a critical role in Earth system science and is a reflection of human activities and environmental changes. LUCC will affect the structure and function of ecosystems and a series of other terrestrial surface processes, such as energy exchange, water circulation, biogeochemical circulation, and vegetation productivity. Therefore, accurate LUCC mapping and vegetation cover monitoring are the bases for simulating the global carbon and hydrological cycles, studying the interactions of the land surface and climate, and assessing land degradation. Based on field GPS surveys and UAV data, with cloud-free and snow/glacier algorithms and the SVM classifier to train and model alpine grassland, the alpine grassland and LUCC were extracted by using Landsat-8 OLI satellite images in Sanjiangyuan National Park in this paper. The latest datasets of vegetation types with 30 m x 30 m spatial resolution in the three parks were prepared and formed. The classification results show that the SVM classifier could better distinguish the major land-use types, and the overall classification accuracy was very high. However, in the alpine grassland subcategories, the classification accuracies of the four typical grasslands were relatively low, especially between desert steppes and alpine meadows, and desert steppes and alpine steppes. It manifests the limitations of Landsat-8 multispectral remote sensing imageries in finer-resolution grassland classifications of high-altitude alpine mountains. The method can be utilized for other multispectral satellite imageries with the same band matching, such as Landsat 7, Landsat 9, Sentinel-2, etc. The method described in this paper can rapidly and efficiently process annual alpine grassland maps of the source areas of the Yellow River, the Yangtze River, and the Lancang River. It can provide timely and high-spatial-resolution datasets for supporting scientific decisions for the sustainable management of Sanjiangyuan National Park. C1 [Wei, Yanqiang; Tang, Xuejie; Hu, Huawei; Wang, Xufeng] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou 730000, Peoples R China. [Wang, Wenwen] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Tang, Xuejie] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Li, Hui] Chinese Acad Sci, Lanzhou Informat Ctr, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. [Hu, Huawei] Qinghai Normal Univ, Coll Geosci, Xining 810008, Peoples R China. RP Wang, XF (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou 730000, Peoples R China. EM weiyq@lzb.ac.cn; wangwenwen@ucas.ac.cn; sixyearstang@163.com; lih@llas.ac.cn; huhuawei19840618@163.com; wangxufeng@lzb.ac.cn TC 3 Z9 3 PD AUG PY 2022 VL 14 IS 15 AR 3714 DI 10.3390/rs14153714 UT WOS:000839878400001 DA 2023-03-23 ER PT J AU Xu, DH Mou, WB Wang, XJ Zhang, RY Gao, TP Ai, DXC Yuan, JL Zhang, RY Fang, XW AF Xu, Danghui Mou, Wenbo Wang, Xiejun Zhang, Ruiying Gao, Tianpeng Ai, Dexiecuo Yuan, Jianli Zhang, Renyi Fang, Xiangwen TI Consistent responses of ecosystem CO2 exchange to grassland degradation in alpine meadow of the Qinghai-Tibetan Plateau SO ECOLOGICAL INDICATORS DT Article AB The effect of grassland degeneration on the emissions and sinks of carbon dioxide (CO2) received extensive attention because of the increase of degraded area and the degeneration level in alpine meadow. To quantify its effect, we investigated net ecosystem exchange (NEE), gross primary productivity (GPP), ecosystem respiration (Reco), plant respiration (Rplant) and heterotrophic respiration (Rh), as well as environmental variability (soil water content (SWC), soil total carbon (STC), soil total nitrogen content (STN) and aboveground biomass (AGB)) from different degraded grasslands and non-degraded (ND) grassland in alpine meadow, Qinghai-Tibetan Plateau in growing season. The results indicated that compared with ND grassland, land degradation significantly decreased net CO2 uptake (-NEE), GPP, Reco, Rplant and Rh by 60.61%, 63.22%, 67.53% 78.82% and 43.56%, respectively in extremely degraded (ED) grassland. These consistent responses suggested that the ecosystem CO2 fluxes were very sensitive to grassland degradation. Degradation also decreased Rplant/Reco and Rplant/GPP by 16.8% and 8.1%, respectively, while increased Rh/Reco, Rh/Rplant and Rh/GPP by 16.8%, 41.4% and 3.8%, respectively, suggested that grassland degradation could eventually shifted Reco from autotrophic dominated to heterotrophic dominated. Four structural equation models (SEM) indicated that decline in NEE, GPP and Reco directly related to AGB and STC and decline in Rplant directly related to AGB, and indirectly related to SWC and STN. Our study highlighted that the consistent responses of CO2 fluxes to grassland degradation could alter the ecosystem's carbon balance, and further would be influence carbon-climate feedbacks under deterioration of ecological environment. C1 [Xu, Danghui; Mou, Wenbo; Wang, Xiejun; Zhang, Ruiying; Ai, Dexiecuo; Yuan, Jianli; Zhang, Renyi; Fang, Xiangwen] Lanzhou Univ, Coll Ecol, State Key Lab Grassland Agroecosystems, 222, South Tianshui Rd, Lanzhou 730000, Gansu, Peoples R China. [Gao, Tianpeng] Lanzhou City Univ, Engn Res Ctr Min Pollut Treatment & Ecol Restorat, Lanzhou 730070, Peoples R China. [Gao, Tianpeng] Xian Univ, Sch Biol & Environm Engn, Xian 710065, Peoples R China. RP Xu, DH (通讯作者)，Lanzhou Univ, Coll Ecol, State Key Lab Grassland Agroecosystems, 222, South Tianshui Rd, Lanzhou 730000, Gansu, Peoples R China. EM dhxu@lzu.edu.cn TC 1 Z9 1 PD AUG PY 2022 VL 141 AR 109036 DI 10.1016/j.ecolind.2022.109036 UT WOS:000818657000006 DA 2023-03-23 ER PT J AU Wang, SR Jiao, CC Zhao, DY Zeng, J Xing, P Liu, YQ Wu, QL AF Wang, Shuren Jiao, Congcong Zhao, Dayong Zeng, Jin Xing, Peng Liu, Yongqin Wu, Qinglong L. TI Disentangling the assembly mechanisms of bacterial communities in a transition zone between the alpine steppe and alpine meadow ecosystems on the Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Alpine meadows and alpine steppes are two major grassland types distributed on the Tibetan Plateau. Due in large part to the differences in hydrothermal and nutrient conditions following the thawing of lakeshore permafrost, alpine meadows and alpine steppes which are characterized by disparate above- and below-ground biomass, could emerge together in the grassland transition zone between meadows and steppes of the Tibetan Plateau. Bacterial communities are essential components of alpine grassland ecosystems and respond rapidly to environmental changes. Despite their ecological significance, it remains poorly elucidated whether and how the assembly patterns of bacterial communities differed between alpine meadows and alpine steppes. Here, to disentangle the assembly mechanisms of bacterial communities from alpine meadows and alpine steppes, we collected samples from three diverse habitats (i.e., sediments, rhizosphere soils and bulk soils) in both alpine meadow and steppe ecosystems on the Tibetan Plateau. Our results indicated that in both meadows and steppes, rhizosphere bacterial communities exhibited higher alpha-diversity but lower beta-diversity compared to the bacterial communities in sediments and bulk soils. However, the close relationships of bacterial communities between different habitats weakened from meadows to steppes. Null model analysis indicated that the importance of environmental selection shaping bacterial community assemblages in all habitats decreased from meadows to steppes, whereas the role of dispersal limitation showed an opposite pattern. Moreover, pH was the primary driver of phylogenetic turnover of bacterial communities in the steppes across all habitats, whereas the dominant drivers of phylogenetic turnover of bacterial communities in meadows varied with habitat types. Overall, our findings provide novel insights into understanding the differences in microbial communities between meadows and steppes in the grassland transition zone on the Tibetan Plateau. C1 [Wang, Shuren; Jiao, Congcong; Zhao, Dayong] Hohai Univ, Joint Int Res Lab Global Change & Water Cycle, State Key Lab Hydrol Water Resources & Hydraul En, Nanjing, Peoples R China. [Wang, Shuren; Jiao, Congcong; Zeng, Jin; Xing, Peng; Wu, Qinglong L.] Chinese Acad Sci, Nanjing Inst Geog & Limnol, State Key Lab Lake Sci & Environm, Nanjing, Peoples R China. [Liu, Yongqin] Lanzhou Univ, Ctr Pan third Pole Environm, Lanzhou, Peoples R China. [Liu, Yongqin] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing, Peoples R China. [Wu, Qinglong L.] Univ Chinese Acad Sci, Sino Danish Ctr Educ & Res, Beijing, Peoples R China. [Zeng, Jin] Chinese Acad Sci, Nanjing Inst Geog & Limnol, 73 East Beijing Rd, Nanjing 210008, Peoples R China. RP Zeng, J (通讯作者)，Chinese Acad Sci, Nanjing Inst Geog & Limnol, 73 East Beijing Rd, Nanjing 210008, Peoples R China. EM jzeng@niglas.ac.cn TC 0 Z9 0 PD NOV 15 PY 2022 VL 847 AR 157446 DI 10.1016/j.scitotenv.2022.157446 EA JUL 2022 UT WOS:000882803300002 DA 2023-03-23 ER PT J AU Ma, N Zhang, YQ AF Ma, Ning Zhang, Yongqiang TI Contrasting Trends in Water Use Efficiency of the Alpine Grassland in Tibetan Plateau SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES DT Article AB Alpine grassland is the dominant land cover type of the Tibetan Plateau (TP). Previous studies suggested that TP's climate and vegetation condition have changed substantially in past few decades. However, the impacts of such changes on ecosystem water use efficiency (WUE), a vital index for depicting the tradeoff between water loss and carbon gain, of alpine grassland remain poorly understood. This study used a water-carbon coupled model, Penman-Monteith-Leuning Version 2 (PML_V2), to investigate the variation in WUE of alpine grassland in the TP during 1982-2016 and its drivers. PML_V2 performs well in estimating WUE at nine eddy-covariance flux sites, noticeably better than other main-stream products. The long-term mean WUE decreases from the southeastern to the northwestern TP, generally following the spatial pattens of surface greenness and climatic condition. During 1982-2016, WUE increased in most parts (71%) of alpine grassland but declined in certain regions of western TP. At the ecosystem scale, contrasting trends in WUE emerged between alpine meadow and alpine steppe over the last 35 years. The former's significant increasing WUE was primarily driven by increased leaf area index (LAI) and CO2 concentration (eCO(2)). While greening also occurred in the latter, its WUE remained stable because (a) the large negative effect of precipitation offset the positive effect of LAI on WUE, and; (b) the enhancement of photosynthesis resulted from elevated eCO(2) was weaker because of low LAI. Our results are of importance for understanding the dynamics and mechanisms of water-carbon coupling in high-elevation ecosystems under a changing climate. C1 [Ma, Ning; Zhang, Yongqiang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Water Cycle & Related Land Surface Proc, Beijing, Peoples R China. RP Ma, N; Zhang, YQ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Water Cycle & Related Land Surface Proc, Beijing, Peoples R China. EM ningma@igsnrr.ac.cn; zhangyq@igsnrr.ac.cn TC 0 Z9 0 PD JUL 27 PY 2022 VL 127 IS 14 AR e2022JD036919 DI 10.1029/2022JD036919 UT WOS:000827885900001 DA 2023-03-23 ER PT J AU Pan, Y Zhu, J Zhang, YJ Li, ZN Wu, JX AF Pan, Ying Zhu, Jin Zhang, Yanjie Li, Zhennan Wu, Junxi TI Poverty eradication and ecological resource security in development of the Tibetan Plateau SO RESOURCES CONSERVATION AND RECYCLING DT Article AB In 2021, China announced the elimination of extreme poverty nationally. One region of extreme poverty in China was the Tibetan Plateau, which provides crucial ecosystem services. It is important that measures intended to eradicate poverty on the Tibetan Plateau do not sacrifice ecological resource security and cause ecosystem degradation. In this study, the variations of the relationships between poverty eradication and ecological resource security were analyzed by defining the relationships into four patterns of poverty traps, economic development with ecological resource deficit, poverty with reserve ecological resources, and sustainable development. The variations of the four patterns during the previous three decades were analyzed and future variations were estimated under different scenarios of ecological resource consumption. Results showed that consumption of the ecological resources of the Tibetan Plateau increased during the previous three decades, with the average value changing from 119.0 to 180.8 g C m(-2) a(-1). Most counties in poverty with reserve ecological resources have become counties with sustainable development, and ecological restoration has benefitted ecological security substantially. However, it has been difficult for counties in poverty traps and with ecological deficit to become counties with sustainable development because the ecological deficit could not be reversed owing to the ever-increasing consumption of ecological resources associated with improved living standards. Scenario simulations revealed that many counties currently exhibiting sustainable development would slip back into ecological deficit in coming decades if consumption of ecological resources associated with production and personal living standards continued increasing, or even remained constant at the average level of the previous decade. Therefore, to support long-lasting sustainable development of the Tibetan Plateau, policies should be proposed that simultaneously enhance ecological restoration and break the link between ecological resource use and economic development. C1 [Pan, Ying; Zhu, Jin; Li, Zhennan; Wu, Junxi] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Zhu, Jin; Li, Zhennan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Yanjie] Dali Univ, Coll Agr & Biol Sci, Dali 671003, Peoples R China. [Pan, Ying] Inst Geog Sci, Nat Resources Res Chinese Acad Sci, 11A, Datun Rd,Chaoyang Dist, Beijing 100101, Peoples R China. RP Pan, Y (通讯作者)，Inst Geog Sci, Nat Resources Res Chinese Acad Sci, 11A, Datun Rd,Chaoyang Dist, Beijing 100101, Peoples R China. EM panying@igsnrr.ac.cn TC 3 Z9 3 PD NOV PY 2022 VL 186 AR 106552 DI 10.1016/j.resconrec.2022.106552 EA JUL 2022 UT WOS:000835495800009 DA 2023-03-23 ER PT J AU Wang, LL Ren, F Zhang, C Huang, XJ Zhang, ZH He, JS Yang, YP Duan, YW AF Wang, Lin-Lin Ren, Fei Zhang, Chan Huang, Xiao-Juan Zhang, Zhen-Hua He, Jin-Sheng Yang, Yong-Ping Duan, Yuan-Wen TI The effects of changes in flowering plant composition caused by nitrogen and phosphorus enrichment on plant-pollinator interactions in a Tibetan alpine grassland SO FRONTIERS IN PLANT SCIENCE DT Article AB Soil eutrophication from atmospheric deposition and fertilization threatens biodiversity and the functioning of terrestrial ecosystems worldwide. Increases in soil nitrogen (N) and phosphorus (P) content can alter the biomass and structure of plant communities in grassland ecosystems; however, the impact of these changes on plant-pollinator interactions is not yet clear. In this study, we tested how changes in flowering plant diversity and composition due to N and P enrichment affected pollinator communities and pollination interactions. Our experiments, conducted in a Tibetan alpine grassland, included four fertilization treatments: N (10 g N m(-2) year(-1)), P (5 g P m(-2) year(-1)), a combination of N and P (N + P), and control. We found that changes in flowering plant composition and diversity under the N and P treatments did not alter the pollinator richness or abundance. The N and P treatments also had limited effects on the plant-pollinator interactions, including the interaction numbers, visit numbers, plant and pollinator species dissimilarity, plant-pollinator interaction dissimilarity, average number of pollinator species attracted by each plant species (vulnerability), and average number of plant species visited by each pollinator species (generality). However, the N + P treatment increased the species and interaction dissimilarity in flowering plant and pollinator communities and decreased the generality in plant-pollinator interactions. These data highlight that changes in flowering plants caused by N + P enrichment alter pollination interactions between flowering plants and pollinators. Owing to changes in flowering plant communities, the plant-pollinator interactions could be sensitive to the changing environment in alpine regions. C1 [Wang, Lin-Lin; Yang, Yong-Ping; Duan, Yuan-Wen] Kunming Inst Bot, Chinese Acad Sci, Germplasm Bank Wild Species, Kunming, Peoples R China. [Wang, Lin-Lin; Yang, Yong-Ping; Duan, Yuan-Wen] Inst Tibetan Plateau Res Kunming, Kunming Inst Bot, Chinese Acad Sci, Kunming, Peoples R China. [Ren, Fei] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Zhang, Chan] Henan Normal Univ, Coll Life Sci, Xinxiang, Peoples R China. [Huang, Xiao-Juan] Northwest Univ, Coll Life Sci, Xian, Peoples R China. [Huang, Xiao-Juan] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhang, Zhen-Hua] Northwest Inst Plateau Biol, Chinese Acad Sci, Key Lab Adaptat & Evolutionof Plateau Biota, Haibei Alpine Grassland Ecosyst Res Stn, Xining, Peoples R China. [He, Jin-Sheng] Peking Univ, Dept Ecol, Minist Educ, Key Lab Earth Surface Proc, Beijing, Peoples R China. [He, Jin-Sheng] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. RP Yang, YP; Duan, YW (通讯作者)，Kunming Inst Bot, Chinese Acad Sci, Germplasm Bank Wild Species, Kunming, Peoples R China.; Yang, YP; Duan, YW (通讯作者)，Inst Tibetan Plateau Res Kunming, Kunming Inst Bot, Chinese Acad Sci, Kunming, Peoples R China.; He, JS (通讯作者)，Peking Univ, Dept Ecol, Minist Educ, Key Lab Earth Surface Proc, Beijing, Peoples R China.; He, JS (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. EM jshe@pku.edu.cn; yangyp@mail.kib.ac.cn; duanyw@mail.kib.ac.cn TC 0 Z9 0 PD JUL 25 PY 2022 VL 13 AR 964109 DI 10.3389/fpls.2022.964109 UT WOS:000891358400001 DA 2023-03-23 ER PT J AU Yang, JW Wang, SJ Su, WH Yu, QL Wang, XC Han, Q Zheng, YT Qu, JP Li, XZ Li, H AF Yang, Jiawei Wang, Sijie Su, Wanghong Yu, Qiaoling Wang, Xiaochen Han, Qian Zheng, Yuting Qu, Jiapeng Li, Xiangzhen Li, Huan TI Animal Activities of the Key Herbivore Plateau Pika (Ochotona curzoniae) on the Qinghai-Tibetan Plateau Affect Grassland Microbial Networks and Ecosystem Functions SO FRONTIERS IN MICROBIOLOGY DT Article AB Plateau pikas (Ochotona curzoniae) are high-altitude model animals and famous "ecosystem engineers" on the Qinghai-Tibet Plateau. Pika activities may accelerate the degradation of alpine meadows. Nevertheless, little is known about the responses of bacterial, fungal, and archaeal communities, and ecosystem multifunctionality to pika perturbations. To address this question, we studied the impacts of only pika disturbance and combined disturbance (pika disturbance and grazing) on ecological networks of soil microbial communities and ecosystem multifunctionality. Our results demonstrated that Proteobacteria, Ascomycota, and Crenarchaeota were dominant in bacteria, fungi, and archaea, respectively. Bacteria, fungi, and archaea were all influenced by the combined disturbance of grazing and pika. Most fungal communities became convergent, while bacterial and archaeal communities became differentiated during the succession of surface types. In particular, the bacterial and fungal networks were less stable than archaeal networks. In response to the interference, cross-domain cooperation between bacterial and fungal communities increased, while competitive interactions between bacterial and archaeal communities increased. Pika disturbance at high intensity significantly reduced the ecosystem multifunctionality. However, the mixed effects of grazing and pika weakened such influences. This study revealed how pika activities affected microbial networks and ecosystem multifunctionality. These results provide insights to designing reasonable ecological management strategies for alpine grassland ecosystems. C1 [Yang, Jiawei; Wang, Sijie; Su, Wanghong; Yu, Qiaoling; Wang, Xiaochen; Han, Qian; Li, Huan] Lanzhou Univ, Sch Publ Hlth, Lanzhou, Peoples R China. [Zheng, Yuting] Changsha Cent South Forestry Survey Planning & Des, Changsha, Peoples R China. [Qu, Jiapeng] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining, Peoples R China. [Qu, Jiapeng; Li, Huan] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. [Li, Xiangzhen] Chinese Acad Sci, Chengdu Inst Biol, Key Lab Environm & Appl Microbiol, Environm Microbiol Key Lab Sichuan Prov, Chengdu, Peoples R China. [Li, Huan] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Ctr Grassland Microbiome, State Key Lab Grassland Agroecosystems, Lanzhou, Peoples R China. RP Li, H (通讯作者)，Lanzhou Univ, Sch Publ Hlth, Lanzhou, Peoples R China.; Qu, JP (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining, Peoples R China.; Qu, JP; Li, H (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China.; Li, XZ (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Key Lab Environm & Appl Microbiol, Environm Microbiol Key Lab Sichuan Prov, Chengdu, Peoples R China.; Li, H (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Ctr Grassland Microbiome, State Key Lab Grassland Agroecosystems, Lanzhou, Peoples R China. EM jpqu@nwipb.cas.cn; lixz@cib.ac.cn; lihuanzky@163.com TC 0 Z9 0 PD JUL 6 PY 2022 VL 13 AR 950811 DI 10.3389/fmicb.2022.950811 UT WOS:000829417700001 DA 2023-03-23 ER PT J AU Liu, LK Zhao, GJ An, ZF Mu, XM Jiao, JY An, SS Tian, P AF Liu, Likun Zhao, Guangju An, Zhengfeng Mu, Xingmin Jiao, Juying An, Shaoshan Tian, Peng TI Effect of grazing intensity on alpine meadow soil quality in the eastern Qinghai-Tibet Plateau, China SO ECOLOGICAL INDICATORS DT Article AB Grazing plays a critical role in the sustainable development of grassland. It has been convinced that grazing affects grassland productivity, however, researches on the relationship between grazing intensity and grassland soil quality remain inadequate in the alpine environment. This study compared ten soil quality indexes (SQIs) to quantitative assess the effect of different grazing intensities [no grazing (NG); light grazing (LG); moderate grazing (MG); heavy grazing (HG)] on the soil quality of alpine meadow in the 0-10 cm and 10-20 cm soil layers. Principal component analysis (PCA) and minimum data set (MDS) were applied to indicator selection and weight assignment. The fitting relationship and correlation between SQI-TDS and SQI-MDSs and the sensitivity index (SI) of ten SQIs were used to select the optimal SQI method. Our results showed that compared with NG and LG, HG and MG significantly decreased soil organic matter (SOM), total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), and cation exchange capacity (CEC) (p < 0.05), whereas increased bulk density (BD) and pH. Besides, TN, TP, TK, SOM, Sand content, soil phosphatase activity (PHO), soil sucrase activity (SUC), and soil catalase activity (CAT) could well replace the TDS method to evaluate soil quality. The SQI calculated by the MDS4 with the non-linear scoring method (SQI-NL-MDS4) had the best performance in soil quality evaluation among ten SQIs. Compared with NG and LG, HG had a stronger negative effect on alpine meadow soil quality, especially in the 0-10 cm soil layer, which potentially aggravated leading to aggravating grassland degradation. We propose that reasonable grazing intensity management should be advocated to maintain the sustainable development of alpine meadow productivity. C1 [Liu, Likun; Zhao, Guangju; Mu, Xingmin; Jiao, Juying; An, Shaoshan] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, 26 Xinong Rd, Yangling 712100, Shaanxi, Peoples R China. [Zhao, Guangju; Mu, Xingmin; Jiao, Juying; An, Shaoshan] Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, Xinong Rd 26, Yangling 712100, Shaanxi, Peoples R China. [An, Zhengfeng] Univ Alberta, Dept Renewable Resources, 442 Earth Sci Bldg, Edmonton, AB, Canada. [Tian, Peng] Northwest A&F Univ, Coll Nat Resources & Environm, 26 Xinong Rd, Yangling 712100, Shaanxi, Peoples R China. [Zhao, Guangju] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, 26 Xinong Rd, Yangling 712100, Shaanxi, Peoples R China. RP Zhao, GJ (通讯作者)，Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess Pl, 26 Xinong Rd, Yangling 712100, Shaanxi, Peoples R China. EM gjzhao@ms.iswc.ac.cn TC 4 Z9 4 PD AUG PY 2022 VL 141 AR 109111 DI 10.1016/j.ecolind.2022.109111 EA JUL 2022 UT WOS:000856110100003 DA 2023-03-23 ER PT J AU Hao, XH Yang, JJ Dong, SK Shen, H He, FC Zhi, YL Kwaku, EA Tu, DJ Dou, SY Zhou, XL Yang, ZR AF Hao, Xinghai Yang, Juejie Dong, Shikui Shen, Hao He, Fengcai Zhi, Yangliu Kwaku, Emmanuella A. Tu, Danjia Dou, Shengyun Zhou, Xueli Yang, Zhengrong TI Impacts of Short-Term Grazing Intensity on the Plant Diversity and Ecosystem Function of Alpine Steppe on the Qinghai-Tibetan Plateau SO PLANTS-BASEL DT Article AB Livestock grazing is the primary land use of grasslands worldwide. Grazing has been asserted to alter grassland ecosystem functions, such as productivity, nutrient cycling, and biodiversity conservation. However, few studies have focused on the impact of grazing intensity on the ecosystem multifunctionality (EMF) of alpine grasslands. We conducted a field experiment of manipulating sheep grazing intensity effects on alpine steppe by surveying plant community characteristics and ecosystem functions. Our results showed that plant community composition was altered with increasing grazing intensity, and the dominant species shifted from grasses and sedges to forbs. EMF was the highest under no grazing (CK) and the lowest under heavy grazing (HG), but there was insignificant difference between CK and HG. HG significantly decreased some indicators that reflected nutrient cycling functions, such as soil available nitrogen, plant leaf nitrogen (PN) and phosphorus content (PP). Furthermore, plant diversity had strong correlations with SOC, total nitrogen (TN), and PN. The results could provide scientific bases for biodiversity conservation and sustainable grazing management of alpine steppe. C1 [Hao, Xinghai; Yang, Juejie; Dong, Shikui; Shen, Hao; He, Fengcai] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. [Dong, Shikui; Zhi, Yangliu; Kwaku, Emmanuella A.] Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. [Tu, Danjia; Dou, Shengyun; Zhou, Xueli; Yang, Zhengrong] Grassland Improvement Expt Stn Qinghai Prov, Gonghe 813099, Peoples R China. RP Yang, JJ; Dong, SK (通讯作者)，Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China.; Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. EM hxh199801@163.com; yangjuejie@bjfu.edu.cn; dongshikui@bjfu.edu.cn; shenhao2222@gmail.com; fengcai_he0327@163.com; yangliu_zhi@163.com; emmkwaku.17@gmail.com; tdjqh2022@163.com; tiebujiacaoye@126.com; zhouxuelia@163.com; 18609716488@163.com TC 1 Z9 1 PD JUL PY 2022 VL 11 IS 14 AR 1889 DI 10.3390/plants11141889 UT WOS:000832395000001 DA 2023-03-23 ER PT J AU Lan, TL Luo, XX Ma, QG Jiang, WT Xia, HX AF Lan, Tianli Luo, Xiaoxiao Ma, Qinguo Jiang, Wangtao Xia, Huxi TI Desertification Caused by Embankment Construction in Permafrost Environment on the Qinghai-Tibetan Plateau SO ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING DT Article; Early Access AB Desertification is a process of land degradation embodied in soil water reduction, soil deterioration and vegetation degradation. As an important factor to evaluate the desertification degree, the water content of shallow soil will infiltrate downward when permafrost degrades on the Qinghai-Tibet Plateau (QTP). With the development of transportation facilities on the QTP, embankment construction, which will directly change the surface cover and reduces the water content of shallow soil by degrading the permafrost. In this study, an embankment construction in the permafrost region of the QTP was selected and a hydro-thermo-vapor coupling model for the embankment-permafrost system was established. The mechanism and process of desertification caused by permafrost degradation were analyzed by the variations of geotemperature and soil water. The results show that: (1) embankment construction has increased the heat flowing into the ground, warmed the underlying permafrost and deepened the permafrost table by more than 10 m during 50 years. (2) Accompanied with the permafrost degradation, the shallow soil water migrates downward and accumulates near the deepening permafrost table, showing a funnel-shaped distribution. The average water content of shallow soil under the changed surface has decreased by 5-6% during 50 years, indicating the intensification of desertification. (3) Desertification and permafrost degradation on the QTP is interconnected by the redistribution of soil water. Desertification and permafrost degradation are the mutual promotion process on the QTP. C1 [Lan, Tianli; Luo, Xiaoxiao; Ma, Qinguo; Jiang, Wangtao; Xia, Huxi] South China Univ Technol, State Key Lab Subtrop Bldg Sci, Guangzhou 510641, Guangdong, Peoples R China. [Ma, Qinguo] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. RP Ma, QG (通讯作者)，South China Univ Technol, State Key Lab Subtrop Bldg Sci, Guangzhou 510641, Guangdong, Peoples R China.; Ma, QG (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. EM maqg@scut.edu.cn TC 0 Z9 0 DI 10.1007/s13369-022-06988-y EA JUL 2022 UT WOS:000819699100001 DA 2023-03-23 ER PT J AU Yang, T Li, Q Zou, Q Hamdi, R Cui, FQ Li, LH AF Yang, Tao Li, Qian Zou, Qiang Hamdi, Rafiq Cui, Fengqi Li, Lanhai TI Impact of Snowpack on the Land Surface Phenology in the Tianshan Mountains, Central Asia SO REMOTE SENSING DT Article AB The accumulation and ablation processes of seasonal snow significantly affect the land surface phenology in a mountainous ecosystem. However, the ability of snow to regulate the alpine land surface phenology in the arid regions is not well described in the context of climate change. The impact of snowpack changes on land surface phenology and its driving factors were investigated in the Tianshan Mountains using the land surface phenology metrics derived from satellited products and a snow dataset from downscaled regional climate model simulations covering the period from 1983 to 2015. The results demonstrated that the annual mean start of growing season (SOS) and length of growing season (LOS) experienced a significant (p < 0.05) decrease and increase with a rate of -2.45 days/decade and 2.98 days/decade, respectively. The significantly advanced SOS and increased LOS were mainly seen in the Western Tianshan Mountains and Ili Valley regions with elevations from 2500 to 3500 m a.s.l and below 3000 m a.s.l, respectively. During the early spring, the significant decline in snow cover fraction (SCF) could advance the SOS. In contrast, snowmelt amount and annual maximum snow water equivalent (SWE) have an almost equally substantial positive correlation with annual maximum vegetation greenness. In particular, the SOS of grassland was the most sensitive to variations of snow cover fraction during early spring than that of other vegetation types, and their strong relationship was mainly located at elevations from 1500 to 2500 m a.s.l. Its greenness was significantly controlled by the annual maximum snow water equivalent in all elevation bands. Both decreased SCF and increased temperature in the early spring caused a significant advance of the SOS, consequently prolonging the LOS. Meanwhile, more SWE and snowmelt amount could significantly promote vegetation greenness by regulating the soil moisture. The results can improve the understanding of the snow ecosystem services in the alpine regions under climate change. C1 [Yang, Tao; Zou, Qiang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Hazards & Surface Proc, Chengdu 610041, Peoples R China. [Li, Qian; Li, Lanhai] Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China. [Li, Qian; Li, Lanhai] Chinese Acad Sci, Ili Stn Watershed Ecosyst Res, Yili 835800, Peoples R China. [Hamdi, Rafiq] Royal Meteorol Inst, Meteorol & Climatol Res Dept, B-1180 Brussels, Belgium. [Cui, Fengqi] Univ Ghent, Dept Geog, B-9000 Ghent, Belgium. [Li, Lanhai] Chinese Acad Sci, Res Ctr Ecol & Environm Cent Asia, Urumqi 830011, Peoples R China. RP Li, LH (通讯作者)，Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China.; Li, LH (通讯作者)，Chinese Acad Sci, Ili Stn Watershed Ecosyst Res, Yili 835800, Peoples R China.; Li, LH (通讯作者)，Chinese Acad Sci, Res Ctr Ecol & Environm Cent Asia, Urumqi 830011, Peoples R China. EM yangtao@imde.ac.cn; liqian@ms.xjb.ac.cn; zouqiang@imde.ac.cn; rafiq.hamdi@meteo.be; fengqi.cui@ugent.be; lilh@ms.xjb.ac.cn TC 3 Z9 3 PD JUL PY 2022 VL 14 IS 14 AR 3462 DI 10.3390/rs14143462 UT WOS:000833259900001 DA 2023-03-23 ER PT J AU Liu, M Zhu, TB Tian, YQ Xu, XL Wang, YF AF Liu, Min Zhu, Tongbin Tian, Yuqiang Xu, Xingliang Wang, Yanfen TI Plant functional groups shift their nitrogen uptake during restoration of degraded alpine grasslands SO LAND DEGRADATION & DEVELOPMENT DT Article AB Alpine grasslands are undergoing severe degradation and are mainly restored through fencing. Numerous studies have explored the patterns, processes, and mechanisms of plant and soil during degradation, but few have been conducted on nitrogen (N) uptake by plant functional groups during restoration. An alpine meadow and an alpine steppe on the Tibetan Plateau were chosen to carry out in situ N-15 labelling experiments in the forms of NH4+, NO3-, and glycine during restoration. Short-, moderate-, and long-term restoration periods were explored, and plants were classified by functional groups into grasses, sedges, and forbs. Our results found biomass of grasses increased and that of sedges decreased with restoration in alpine meadow. In alpine steppe, forbs gradually became dominant in the community biomass by 58% during restoration. Long-term restoration increased NH4+ uptake by grasses in alpine meadow. The total N uptake rates by grasses increased, but by forbs decreased during restoration in alpine meadow. Restoration decreased the total N uptake rates of grasses and forbs in alpine steppe. Chemical niche in N uptake was discovered during long-term restoration in alpine meadow and during moderate-term restoration in alpine steppe. We conclude that restoration alters the biomass composition of grasses, sedges, and forbs in alpine grasslands and shifts N uptake partitions. Chemical niche in N uptake by different functional groups in grasslands during restoration can decrease the fierce competition for N. Our results provide a synthesis for plant N utilization from soil during restoration of degraded grasslands from the perspective of shifting N uptake strategies. C1 [Liu, Min; Xu, Xingliang] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, 11A,Datun Rd, Beijing 100101, Peoples R China. [Liu, Min] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 101408, Peoples R China. [Zhu, Tongbin] Chinese Acad Geol Sci, Karst Dynam Lab, MLR & Guangxi, Inst Karst Geol, Guilin 541004, Peoples R China. [Tian, Yuqiang] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Tian, Yuqiang] Beijing Normal Univ, Fac Geog Sci, Sch Nat Resources, Beijing 100875, Peoples R China. [Wang, Yanfen] Univ Chinese Acad Sci, Coll Life Sci, Beijing 101408, Peoples R China. RP Xu, XL (通讯作者)，Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, 11A,Datun Rd, Beijing 100101, Peoples R China.; Wang, YF (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 101408, Peoples R China. EM xuxl@igsnrr.ac.cn; yfwang@ucas.ac.cn TC 0 Z9 0 PD SEP PY 2022 VL 33 IS 15 BP 2898 EP 2910 DI 10.1002/ldr.4363 EA JUN 2022 UT WOS:000817786400001 DA 2023-03-23 ER PT J AU Wang, L Jing, YY Xu, CL Yu, XJ AF Wang, Lin Jing, Yuanyuan Xu, Changlin Yu, Xiaojun TI Effect of Grazing Treatments on Phenotypic and Reproductive Plasticity of Kobresia humilis in Alpine Meadows of the Qinghai-Tibet Plateau SO FRONTIERS IN ENVIRONMENTAL SCIENCE DT Article AB Plant phenotypic and reproductive plasticity is strongly influenced by long-term grazing activities. It is important to understand the life history of dominant plant species, such as Kobresia humilis of alpine meadow, for the stability and sustainable grazing administration meadow on the Qinghai-Tibetan Plateau (QTP). We compared the effects of different grazing treatments (grazing yak, Y; grazing Tibetan sheep, S; and grazing Tibetan sheep and yak, S+Y) on the reproductive and phenotypic plasticity of K. humilis in an alpine meadows on the northeastern margin of the Qilian Mountains in China. The results showed that different grazing treatments had significantly effects on the K. humilis phenotype and reproductive plasticity. The Y treatment significantly reduced the plant height, crown width and K. humilis biomass, but increased the density, which was 1.27 and 1.53 times higher than that in the S+Y and S treatments, respectively. Further, the S+Y treatment significantly increased the crown width, biomass, and future life expectancy of K. humilis. Whereas the S treatment increased the height of K. humilis significantly, which was 1.57 and 1.10 times higher than that in the Y and S+Y treatments, respectively. Both Y and S treatments significantly increased the sexual reproduction efficacy of K. humilis but reduced the storage efficacy. The storage efficacy at S+Y treatment was highest among these treatments. Further, grazing treatments did not change the resource allocation strategy of K. humilis, while the sexual reproductive efficacy was significantly higher than the vegetative reproduction efficacy. The storage efficacy was significantly higher than the growth efficacy among the different grazing treatments. The increase of Cyperaceae indicates the degradation of Cyperaceae-Poaceae meadows. This study showed that grazing Tibetan sheep is a more sustainable grazing method in cold season pastures of alpine meadows on the QTP. C1 [Wang, Lin; Jing, Yuanyuan; Xu, Changlin; Yu, Xiaojun] Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Minist Educ, Grassland Sci Coll,Grassland Ecosyst Key Lab, Lanzhou, Peoples R China. RP Yu, XJ (通讯作者)，Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Minist Educ, Grassland Sci Coll,Grassland Ecosyst Key Lab, Lanzhou, Peoples R China. EM yuxj@gsau.edu.cn TC 0 Z9 0 PD JUN 24 PY 2022 VL 10 AR 903763 DI 10.3389/fenvs.2022.903763 UT WOS:000827492400001 DA 2023-03-23 ER PT J AU Maurischat, P Lehnert, L Zerres, VHD Tran, TV Kalbitz, K Rinnan, A Li, XG Dorji, T Guggenberger, G AF Maurischat, Philipp Lehnert, Lukas Zerres, Vinzenz H. D. Tran, Tuong Vi Kalbitz, Karsten Rinnan, Asmund Li, Xiao Gang Dorji, Tsechoe Guggenberger, Georg TI The glacial-terrestrial-fluvial pathway: A multiparametrical analysis of spatiotemporal dissolved organic matter variation in three catchments of Lake Nam Co, Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The Tibetan Plateau (TP) is a sensitive alpine environment of global importance, being Asia's water tower, featuring vast ice masses and comprising the world's largest alpine grasslands. Intensified land-use and pronounced global climate change have put pressure on the environment of the TP. We studied the tempo-spatial variability of dissolved organic matter (DOM) to better understand the fluxes of nutrients and energy from terrestrial to aquatic ecosystems in the TP. We used a multiparametrical approach, based on inorganic water chemistry, dissolved organic carbon (DOC) concentration, dissolved organic matter (DOM) characteristics (chromophoric DOM, fluorescence DOM and delta C-13 of DOM) in stream samples of three catchments of the Nam Co watershed and the lake itself. Satellite based plant cover estimates were used to link biogeochemical data to the structure and degradation of vegetation zones in the catchments. Catchment streams showed site-specific DOM signatures inherited fromglaciers, wetlands, groundwater, and Kobresia pygmaea pastures. By comparing streamand lake samples, we found DOM processing and unification by loss of chromophoric DOM-signatures and a change towards an autochthonous source of lake DOM. DOM-diversity was largest in the headwaters of the catchments and heavily modified in terminal aquatic systems. Seasonality was characterized by a minor influence of freshet and by a very strong impact of the Indian summermonsoon onDOMcomposition, with more microbial DOM sources. The DOM of Lake NamCo differed chemically fromstreamwater samples, indicating the lake to be a quasi-marine environment in regards to the degree of chemical modification and sources of DOM. DOM-proved to be a powerful marker to elucidate consequences of land use and climatic change on biogeochemical processes in High Asian alpine ecosystems. C1 [Maurischat, Philipp; Guggenberger, Georg] Leibniz Univ Hannover, Inst Soil Sci, Hannover, Germany. [Lehnert, Lukas; Zerres, Vinzenz H. D.] Ludwig Maximilians Univ Munchen, Dept Geog, Munich, Germany. [Tran, Tuong Vi] Leibniz Univ Hannover, Inst Fluid Mech & Environm Phys Civil Engn, Hannover, Germany. [Kalbitz, Karsten] Tech Univ Dresden, Inst Soil Sci & Site Ecol, Dresden, Germany. [Rinnan, Asmund] Univ Copenhagen, Dept Food Sci, Copenhagen, Denmark. [Li, Xiao Gang] Lanzhou Univ, Sch Life Sci, Lanzhou, Peoples R China. [Dorji, Tsechoe] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Lhasa, Tibet Autonomou, Peoples R China. RP Maurischat, P (通讯作者)，Leibniz Univ Hannover, Inst Soil Sci, Hannover, Germany. EM maurischat@ifbk.uni-hannover.de TC 0 Z9 0 PD SEP 10 PY 2022 VL 838 AR 156542 DI 10.1016/j.scitotenv.2022.156542 EA JUN 2022 PN 4 UT WOS:000865767900009 DA 2023-03-23 ER PT J AU Huang, YZ Xin, ZB Dor-ji, T Wang, YF AF Huang, Yanzhang Xin, Zhongbao Dor-ji, Tsechoe Wang, Yafeng TI Tibetan Plateau greening driven by warming-wetting climate change and ecological restoration in the 21st century SO LAND DEGRADATION & DEVELOPMENT DT Article AB High altitude areas play an essential role in the global climate system, and their fragile ecosystems sensitively respond to climate change and human activities. An improved understanding of the influences of multiple factors on the spatiotemporal dynamics of vegetation is needed. This study aimed to understand further the impacts of climate, geography, and human on vegetation and disentangle the contributions of climate and humans to vegetation changes using the MOD13Q1 enhanced vegetation index (EVI, 2000-2019). Greening was detected for 70% of the Tibetan Plateau under increased warming and wetting in the 21st century. A rise in temperature of up to 0.66 +/- 0.49 degrees C decade(-1) occurred over 2/3 of the Tibetan Plateau, while precipitation increased slightly. In particular, significant greening covered 1/4 of the Tibetan Plateau and occurred within the steppe and desert on the northern due to wetting and ecological protection. Browning depended on urbanization, overgrazing, and lake expansion in 1.9% of the total area. Orbicular browning around lakes accounted for 18.4% of significant browning, and significant browning trends were also detected in densely populated cities situated at low-altitude and flat areas. The EVI was more strongly positively correlated with the annual mean minimum temperature than the annual mean temperature and maximum temperature and was sensitive to extreme low precipitation events. Residual analysis showed that the relative contribution of climate change was 34%, and that of human activities was 66%. A comprehensive description of the vegetation changes on the Tibetan Plateau will help humans to cope with climate change and ecosystem evolution in high altitude. C1 [Huang, Yanzhang; Xin, Zhongbao] Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing 100083, Peoples R China. [Huang, Yanzhang; Xin, Zhongbao] Beijing Forestry Univ, Sch Soil & Water Conservat, CNERN, Jixian Natl Forest Ecosyst Observat & Res Stn, Beijing, Peoples R China. [Dor-ji, Tsechoe] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing, Peoples R China. [Dor-ji, Tsechoe; Wang, Yafeng] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. RP Xin, ZB (通讯作者)，Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing 100083, Peoples R China. EM xinzhongbao@126.com TC 3 Z9 3 PD AUG 30 PY 2022 VL 33 IS 14 BP 2407 EP 2422 DI 10.1002/ldr.4319 EA JUN 2022 UT WOS:000806737000001 DA 2023-03-23 ER PT J AU Yang, QW Pei, XJ Fu, C AF Yang, Qingwen Pei, Xiangjun Fu, Cheng TI Effect of Polymer Mixtures on Physical-Chemical Properties of Sandy Soil and Plant Growth SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Serious desertification problems were found in alpine grassland of the Qinghai-Tibet Plateau, China. The rehabilitation progress of degraded grassland is slow under natural conditions that have low rainfall and large evaporation. Organic agent-solidified soil is one of the most important measurements that limit desertification and grassland conservation-restoration. However, the characteristics of vegetation growth and development in solidified soil need to be studied in depth. This research is based on the modified carboxymethyl cellulose (MCMC) of independent development. Based on the sand soil taken from moving sandy land of Zoige, potted plants were tested in the environmental chamber at the laboratory. The physical, chemical, and biological characteristics of root soil were monitored for more than 7 months. As a result, the plant biomass in the experimental group increased, lodging rate decreased, drought tolerance and survival rate increased, and the number of plant roots and root surface area index, root cross-sectional area ratio, and root volume ratio increased compared with the matched group. It is shown that MCMC can effectively promote plant root development and improve plant drought tolerance and lodging resistance. We also found that, compared with the matched group, the values of the rhizosphere soil mass, root soil mass, and soil crust layer thickness of the experimental group were much higher, meaning that MCMC has strengthened the root soil-fixation ability and soil-crusting ability of plants. The soil nutrient indexes and bioactivity of the experimental group were higher than the matched group, indicating that MCMC has a positive influence on soil maturation. The quantitative description model of soil aging enhancement of MCMC material during root growth and development was established to explore the soil-fixation mechanism of MCMC plant root succession and provided an important scientific basis and technical support for the conservation and restoration of alpine grassland desertification grassland. C1 [Yang, Qingwen; Pei, Xiangjun] Chengdu Univ Technol, State Key Lab Geohazard Prevent & Geoenvironm Prot, Chengdu, Peoples R China. [Yang, Qingwen] Chengdu Univ Technol, Postdoc Res Stn Civil Engn, Chengdu, Peoples R China. [Fu, Cheng] Chengdu Univ Technol, Coll Environm & Civil Engn, Chengdu, Peoples R China. RP Pei, XJ (通讯作者)，Chengdu Univ Technol, State Key Lab Geohazard Prevent & Geoenvironm Prot, Chengdu, Peoples R China.; Fu, C (通讯作者)，Chengdu Univ Technol, Coll Environm & Civil Engn, Chengdu, Peoples R China. EM Peixj0119@tom.com; Fucheng18482175722@163.com TC 0 Z9 0 PD JUN 6 PY 2022 VL 10 AR 889357 DI 10.3389/fevo.2022.889357 UT WOS:000813213800001 DA 2023-03-23 ER PT J AU Abalori, TA Cao, WX Weobong, CAA Li, W Wang, SL Deng, XX AF Abalori, Theophilus Atio Cao, Wenxia Weobong, Conrad Atogi-Akwoa Li, Wen Wang, Shilin Deng, Xiuxia TI Spatial Vegetation Patch Patterns and Their Relation to Environmental Factors in the Alpine Grasslands of the Qilian Mountains SO SUSTAINABILITY DT Article AB Globally, grasslands are affected by climate change and unsustainable management practices which usually leads to transitions from stable, degraded and then to desertification. Spatial vegetation patch configurations are regarded as key indicators of such transitions. Understanding the relationships between this grass-land vegetation and its environment is key to vegetation restoration projects. Spatial vegetation patch patterns were chosen across different soil and topographic conditions. Patch numbers, perimeter, and cover of each patch were measured along transects of each patch type. Using field surveys and multivariate statistical analysis, we investigated the differences in vegetation biomass and distribution and soil properties of four typical alpine plant species patches along with a range of environmental and topographic conditions. It was found that topographic conditions and soil properties, particularly soil moisture explained most of the variation in spatial patch vegetation characteristics and thus control vegetation restoration in the alpine grassland. The Kobresia humilis, Blysmus sinocompressus and Iris lactea patches under the drylands recorded small patch sizes, large patch numbers, low connectivity, and large total perimeter per unit area. Generally, species within the high moisture sites recorded small patch numbers, a large fraction of vegetation cover and a small total perimeter per m(2). Patches in limited soil moisture areas recorded patch configurations indicating they are unstable and undergoing degradation and therefore need urgent restoration attention to forestall their further degradation and its resultant effect of desertification. These results would provide quantitative easy-to-use indicators for vegetation degradation and help in vegetation restoration projects. C1 [Abalori, Theophilus Atio; Cao, Wenxia; Wang, Shilin; Deng, Xiuxia] Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Grassland Ecosyst Key Lab, Minist Educ,Grassland Sci Coll, Lanzhou 730070, Peoples R China. [Weobong, Conrad Atogi-Akwoa] Univ Dev Studies, Fac Nat Resources & Environm, POB 1882, Tamale, Ghana. [Li, Wen] Qinghai Univ, Key Lab Dev Forage Germplasm Qinghai Tibetan Plat, Qinghai Acad Anim Sci & Vet Med, Xining 810003, Peoples R China. RP Cao, WX (通讯作者)，Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Grassland Ecosyst Key Lab, Minist Educ,Grassland Sci Coll, Lanzhou 730070, Peoples R China. EM abalorit@yahoo.com; caowenxia@foxmail.com; conradweobong@yahoo.com; fosuaama994@yahoo.com; mroseirichard@yahoo.com; nanasei2000@gmail.com TC 0 Z9 0 PD JUN PY 2022 VL 14 IS 11 AR 6738 DI 10.3390/su14116738 UT WOS:000808722800001 DA 2023-03-23 ER PT J AU Cao, JJ Jiao, YM Che, RX Holden, NM Zhang, XF Biswas, A Feng, Q AF Cao, Jianjun Jiao, Yumeng Che, Rongxiao Holden, Nicholas M. Zhang, Xiaofang Biswas, Asim Feng, Qi TI The effects of grazer exclosure duration on soilmicrobial communities on the Qinghai-Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB While determining the response of soil microbes to grazer exclosure duration is critical to understanding ecosystem restoration processes, few studies have focused on this issue. With seasonal grazing as a control, microbes of alpine grassland soils under 5, 13, 22, and 39 years of grazer exclosure situated in the eastern part of the Qinghai-Tibetan Plateau, were examined. Microbial diversity was determined through Illumina high-throughput sequencing of the 16S rRNA gene and an internal transcription spacer (ITS). We found that soil bacterial a-diversity showed insignificant differences between seasonal grazing and grazer exclosure and among the grazer exclosures of different durations, while fungal a-diversity under the 5-year grazer exclosure was significantly different from those under the other treatments. Soil microbial community profiles under the 13-, 22-, and 39-year grazer exclosures were significantly different compared to those under the seasonal grazing or 5-year grazer exclosure. Briefly, longer exclosure durations led to a higher relative abundance of multiple copiotrophic microbial lineages (e.g., beta-Proteobacteria, Rhizobiales, and Frankiales), whereas several oligotrophic microbial lineages (e.g., Chloroflexi, Leotiomycetes, and Xylariales) gradually and significantly decreased. Functional predictions suggest that as grazer exclosure duration was extended, the relative abundance of nitrogen fixers increased, while the proportions of plant pathogenic fungi decreased. This indicates that long-term grazer exclosure duration may contribute to enhanced soil nitrogen fixation and grassland health by maintaining plant growth and decreasing the risk of plant disease. However, this may have a resource cost as plant productivity and soil organic carbon both decreased with the extension of grazer exclosure duration. Therefore, the agroecology effect of grazer exclosure duration on the diversity and abundance of soil nitrogen fixing bacteria and plant pathogen fungi, should be given more attention in the cold and humid portion of the Qinghai-Tibetan Plateau. C1 [Cao, Jianjun; Jiao, Yumeng] Northwest Normal Univ, Coll Geog & Environm Sci, Lanzhou 730070, Peoples R China. [Cao, Jianjun] Northwest Normal Univ, Key Lab Ecofunct Polymer Mat, Minist Educ, Lanzhou 730070, Peoples R China. [Cao, Jianjun] Northwest Normal Univ, Coll Geog & Environm Sci, Key Lab Resource Environm & Sustainable Dev Oasis, Lanzhou 730070, Peoples R China. [Che, Rongxiao] Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming 650091, Peoples R China. [Holden, Nicholas M.] Univ Coll Dublin, Agr & Food Sci Ctr, UCD Sch Biosyst & Food Engn, Dublin 4, Ireland. [Zhang, Xiaofang; Feng, Qi] Chinese Acad Sci, Northwest Inst Ecol & Environm Resources, Key Lab Ecohydrol Inland River Basin, Alashan Desert Ecohydrol Expt Res Stn, Lanzhou 730000, Peoples R China. [Zhang, Xiaofang] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Biswas, Asim] Univ Guelph, Sch Environm Sci, 50 Stone Rd East, Guelph, ON N1G 2W1, Canada. RP Che, RX (通讯作者)，Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming 650091, Peoples R China.; Feng, Q (通讯作者)，Chinese Acad Sci, Northwest Inst Ecol & Environm Resources, Key Lab Ecohydrol Inland River Basin, Alashan Desert Ecohydrol Expt Res Stn, Lanzhou 730000, Peoples R China. EM cherongxiao@ynu.edu.cn; qifeng@lzb.ac.cn TC 2 Z9 2 PD SEP 15 PY 2022 VL 839 AR 156238 DI 10.1016/j.scitotenv.2022.156238 EA MAY 2022 UT WOS:000833542600011 DA 2023-03-23 ER PT J AU Teng, YM Zhan, JY Liu, SL Agyemanga, FB Li, ZH Wang, C Liu, W AF Teng, Yanmin Zhan, Jinyan Liu, Shiliang Agyemanga, Frank Boappeah Li, Zhihui Wang, Chao Liu, Wei TI Integrating ecological and social vulnerability assessment in Qinghai Province, China SO PHYSICS AND CHEMISTRY OF THE EARTH DT Article AB Vulnerability assessment has become a critical issue and an important approach for regional sustainable development research. Qinghai Province, which located in the northeast part of the Qinghai-Tibet Plateau, suffers a severe grassland degradation caused by human activities. Grassland degradation constrains the development of local animal husbandry and further affects the vulnerability of social system. In this study, based on the vulnerability assessment framework of exposure-sensitivity-adaptability, two index systems were established including ecological and social aspects. The entropy weight method was used to determine the index weight. The variations of ecological vulnerability (EV) and social vulnerability (SV) of Qinghai Province were assessed from 1995 to 2015. Results showed that EV in Qinghai Province increased from east to west, and decreased from north to south, while SV showed an opposite trend. Key ecologically fragile areas were mainly located in the Qaidam Basin and western Three-River Headwaters Region, while key SV areas were mainly distributed in the Qilian Mountains and eastern Three-River Headwaters Region. The overall EV showed a decreasing trend through time, but increased in several local areas. SV dropped significantly during study period, especially in the eastern part of Qinghai Province. The results will help to identify key vulnerable areas of Qinghai Province and provide a reference for the region to formulate sustainable development strategies. C1 [Teng, Yanmin; Zhan, Jinyan; Liu, Shiliang; Agyemanga, Frank Boappeah; Wang, Chao; Liu, Wei] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Li, Zhihui] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. RP Zhan, JY (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM zhanjy@bnu.edu.cn TC 6 Z9 6 PD JUN PY 2022 VL 126 AR 103115 DI 10.1016/j.pce.2022.103115 EA MAY 2022 UT WOS:000807375700002 DA 2023-03-23 ER PT J AU Li, T Cui, LZ Scotton, M Dong, JF Xu, ZH Che, RX Tang, L Cai, SH Wu, WC Andreatta, D Wang, YF Song, XF Hao, YB Cui, XY AF Li, Tong Cui, Lizhen Scotton, Michele Dong, Junfu Xu, Zhihong Che, Rongxiao Tang, Li Cai, Shuohao Wu, Wenchao Andreatta, Davide Wang, Yanfen Song, Xiufang Hao, Yanbin Cui, Xiaoyong TI Characteristics and trends of grassland degradation research SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Purpose Grasslands are the largest type of terrestrial ecosystem on the earth, providing rich and unique ecosystem services. However, climate change and human activities have triggered a global degradation of grasslands, which has become a major ecological crisis. In this study, a scientometric analysis was performed to explore the hotspots and frontiers of global grassland degradation research. Materials and methods Two methods involving visualization were used to analyze these data: document co-citation analysis and burst analysis based on the papers indexed in the Web of Science (WOS) during 1970-2020. Results and discussion A total of 3580 research papers related to grassland degradation research and 54,666 references were included. The results showed that Harris's paper in 2010 had the strongest burst value of 26.2, far larger than any other, which shows that this paper was a turning point in the research process. The document co-citation network was divided into 14 main theme clusters. The most influential and emerging research theme clusters were including alpine meadow, grazing exclusion, alpine region, and human activities. Alpine meadow was the largest cluster lasting from 2010 to 2020, indicating that this topic is still active in grassland degradation research. Furthermore, research focus has transferred toward grasslands in Qinghai-Tibetan Plateau. The topic of grazing exclusion is both classic and currently active as it lasted as a research hotspot for 15 years (2004-2018). However, the extent and state of grazing effects research are unclear. Conclusions As the first scientometric review on grassland degradation research, our study identified the research hotspots and their shifts over the past 50 years, pointing to some potential research frontiers in the future. The scientometric analysis is a useful tool for a quantitative evaluation of research hotspots and trends of global grassland degradation. C1 [Li, Tong; Dong, Junfu; Tang, Li; Cai, Shuohao; Wang, Yanfen] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Li, Tong; Xu, Zhihong; Tang, Li] Griffith Univ, Sch Environm & Sci, Ctr Planetary Hlth & Food Secur, Nathan, Qld 4111, Australia. [Li, Tong; Cui, Lizhen; Tang, Li; Wu, Wenchao; Hao, Yanbin; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Scotton, Michele; Andreatta, Davide] Univ Padua, Dept Agron Anim & Environm, Nat Resources, I-35020 Foodlegnaro, Italy. [Dong, Junfu] Shandong Univ, Inst Marine Sci & Technol, Qingdao 266237, Peoples R China. [Che, Rongxiao] Yunnan Univ, Inst Int Rivers & Eco Secur, Kunming 650091, Yunnan, Peoples R China. [Wang, Yanfen; Hao, Yanbin; Cui, Xiaoyong] Beijing Yanshan Earth Crit Zone Natl Res Stn, Beijing 100049, Peoples R China. [Song, Xiufang] Chinese Acad Sci, Natl Sci Lib, Beijing 100190, Peoples R China. RP Xu, ZH (通讯作者)，Griffith Univ, Sch Environm & Sci, Ctr Planetary Hlth & Food Secur, Nathan, Qld 4111, Australia.; Cui, XY (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China.; Cui, XY (通讯作者)，Beijing Yanshan Earth Crit Zone Natl Res Stn, Beijing 100049, Peoples R China. EM zhihong.xu@griffith.edu.au; cuixy@ucas.ac.cn TC 4 Z9 4 PD JUL PY 2022 VL 22 IS 7 BP 1901 EP 1912 DI 10.1007/s11368-022-03209-9 EA MAY 2022 UT WOS:000803118200001 DA 2023-03-23 ER PT J AU Li, T Cai, SH Singh, RK Cui, LZ Fava, F Tang, L Xu, ZH Li, CJ Cui, XY Du, JQ Hao, YB Liu, YX Wang, YF AF Li, Tong Cai, Shuohao Singh, Ranjay K. Cui, Lizhen Fava, Francesco Tang, Li Xu, Zhihong Li, Congjia Cui, Xiaoyong Du, Jianqing Hao, Yanbin Liu, Yuexian Wang, Yanfen TI Livelihood resilience in pastoral communities: Methodological and field insights from Qinghai-Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB as the Qinghai Tibetan Plateau (QTP). This research aimed to fill the gap of assessing herders' livelihood resilience using more inclusive method. Using survey data from 758 pastoralists, complemented with focus group discussions and transect walks in the Three River Headwater Region (TRHR) on the QTP, we first developed a livelihood resilience evaluation index comprising dimensions of buffer capacity, self-organization and learning capacity. The method of entropy-TOPSIS was then applied to assess the livelihood resilience of local herders, and the spatial patterns were analyzed by spatial autocorrelation method. The results showed the overall level of pastoral livelihood resilience resulted weak, with an east to west spatial gradient toward lower livelihood resilience. Self-organization was the most important dimensions of livelihood resilience, with social cohesion being a dominant factor. Buffer capacity resulted the less important, but the natural capital was significantly higher than the other four livelihood capitals. Furthermore, the northeastern region was a hotspot, while the northwestern region was a cold spot of livelihood resilience. While pastoral populations in the TRHR had high self-organization abilities and potentially high learning capacities, the overall low buffer capacity and livelihood capital limited the improvement of their livelihood resilience. The key findings C1 [Li, Tong; Cai, Shuohao; Tang, Li; Du, Jianqing; Liu, Yuexian; Wang, Yanfen] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Li, Tong; Tang, Li; Xu, Zhihong] Griffith Univ, Ctr Planetary Hlth & Food Secur, Sch Environm & Sci, Brisbane, Qld 4111, Australia. [Singh, Ranjay K.] Cent Soil Salin Res Inst, ICAR, Karnal 132001, Haryana, India. [Cui, Lizhen; Li, Congjia; Cui, Xiaoyong; Hao, Yanbin] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Singh, Ranjay K.] Univ Milan, Dept Environm Sci & Policy, Festa Perdono 7, I-20122 Milan, Italy. [Cui, Xiaoyong; Hao, Yanbin; Wang, Yanfen] Beijing Yanshan Earth Crit Zone Natl Res Stn, Beijing 100409, Peoples R China. [Cui, Xiaoyong; Hao, Yanbin; Wang, Yanfen] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. RP Wang, YF (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China.; Cui, XY (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. EM cuixy@ucas.ac.cn; jqdu@ucas.ac.cn; ybhao@ucas.ac.cn; liuyuexian@ucas.ac.cn; yfwang@ucas.ac.cn TC 4 Z9 4 PD SEP 10 PY 2022 VL 838 AR 155960 DI 10.1016/j.scitotenv.2022.155960 EA MAY 2022 PN 2 UT WOS:000806355600014 DA 2023-03-23 ER PT J AU Zhang, ZC Liu, YF Cui, Z Huang, Z Liu, Y Leite, PAM Zhao, JX Wu, GL AF Zhang, Zhenchao Liu, Yi-Fan Cui, Zeng Huang, Ze Liu, Yu Leite, Pedro A. M. Zhao, Jingxue Wu, Gao-Lin TI Shrub encroachment impaired the structure and functioning of alpine meadow communities on the Qinghai-Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Shrub encroachment has been rapidly occurring due to climate change, with profound ecological consequences for the alpine meadows of the Qinghai-Tibetan Plateau. Here, we conducted field surveys along a shrub coverage gradient to examine the effects of shrub encroachment on the structure and functioning of alpine meadows' plant communities. Our results showed that the overall coverage, density, aboveground biomass, species richness, and diversity of meadow community gradually declined with increasing levels of shrub encroachment, especially when shrub coverage exceeded 60%. Aboveground ecosystem multifunctionality also decreased along the shrub coverage gradient. With 90% shrub coverage, the relative importance value of the forbs functional group significantly increased while the Cyperaceae functional group showed the opposite trend: the originally dominant sedges Carex moorcroftii and Kobresia myosuroides were replaced by the forbs Androsace umbellate and Polygonum sparsipilosum. Additionally, shrub encroachment had a strong effect on nonrandom herb species extinction and colonization. At shrub coverages higher than 60%, there were 9 herb species absent and 18 new species colonizing-7 of which were only observed in meadows with 90% shrub coverage. Rare species and those with lower stature were more likely to go extinct, while taller and shade-tolerant species tended to colonize areas with increasing shrub coverage. Overall, our results indicate that shrub encroachment negatively affects herbaceous community structure and functioning, which has important implications for the management of alpine meadows of the Qinghai-Tibetan Plateau under ongoing climate change. C1 [Zhang, Zhenchao; Liu, Yi-Fan; Cui, Zeng; Huang, Ze; Liu, Yu; Wu, Gao-Lin] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China. [Zhang, Zhenchao; Liu, Yi-Fan; Cui, Zeng; Huang, Ze; Liu, Yu; Wu, Gao-Lin] Chinese Acad Sci & Minist Water Resource, Inst Soil & Water Conservat, Yangling, Peoples R China. [Wu, Gao-Lin] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Qinghai Prov Key Lab Adapt Management Alpine Gras, Xining, Peoples R China. [Wu, Gao-Lin] Texas A&M Univ, Dept Ecol & Conservat Biol, College Stn, TX USA. [Zhao, Jingxue] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou, PR, Peoples R China. [Zhao, Jingxue] Lanzhou Univ, Coll Ecol, Lanzhou, Peoples R China. [Wu, Gao-Lin] CAS Ctr Excellence Quaternary Sci & Global Change, Xian, Peoples R China. RP Wu, GL (通讯作者)，Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China. EM wugaolin@nwsuaf.edu.cn TC 0 Z9 0 PD AUG 30 PY 2022 VL 33 IS 14 BP 2454 EP 2463 DI 10.1002/ldr.4323 EA MAY 2022 UT WOS:000799505100001 DA 2023-03-23 ER PT J AU Breidenbach, A Schleuss, PM Liu, SB Schneider, D Dippold, MA de la Haye, T Miehe, G Heitkamp, F Seeber, E Mason-Jones, K Xu, XL Huanming, Y Xu, JC Dorji, T Gube, M Norf, H Meier, J Guggenberger, G Kuzyakov, Y Spielvogel, S AF Breidenbach, Andreas Schleuss, Per-Marten Liu, Shibin Schneider, Dominik Dippold, Michaela A. de la Haye, Tilman Miehe, Georg Heitkamp, Felix Seeber, Elke Mason-Jones, Kyle Xu, Xingliang Huanming, Yang Xu, Jianchu Dorji, Tsechoe Gube, Matthias Norf, Helge Meier, Jutta Guggenberger, Georg Kuzyakov, Yakov Spielvogel, Sandra TI Microbial functional changes mark irreversible course of Tibetan grassland degradation SO NATURE COMMUNICATIONS DT Article AB The Tibetan Plateau's Kobresia pastures store 2.5% of the world's soil organic carbon (SOC). Climate change and overgrazing render their topsoils vulnerable to degradation, with SOC stocks declining by 42% and nitrogen (N) by 33% at severely degraded sites. We resolved these losses into erosion accounting for two-thirds, and decreased carbon (C) input and increased SOC mineralization accounting for the other third, and confirmed these results by comparison with a meta-analysis of 594 observations. The microbial community responded to the degradation through altered taxonomic composition and enzymatic activities. Hydrolytic enzyme activities were reduced, while degradation of the remaining recalcitrant soil organic matter by oxidative enzymes was accelerated, demonstrating a severe shift in microbial functioning. This may irreversibly alter the world ' s largest alpine pastoral ecosystem by diminishing its C sink function and nutrient cycling dynamics, negatively impacting local food security, regional water quality and climate. The Tibetan Kobresia pastures store 2.5% of the world's soil organic carbon. Here the authors show that soil degradation and microbial shifts may irreversibly diminish the carbon sink function and accelerate nutrient losses. C1 [Breidenbach, Andreas; Dippold, Michaela A.] Univ Goettingen, Dept Crop Sci, Biogeochem Agroecosyst, Buesgenweg 2, D-37077 Gottingen, Germany. [Breidenbach, Andreas; Dippold, Michaela A.] Univ Tubingen, Dept Geosci, Geobiosphere Interact, Schnarrenbergstr 94-96, D-72076 Tubingen, Germany. [Schleuss, Per-Marten] Univ Bayreuth, Dept Soil Ecol, Dr Hans Frisch Str 1-3, D-95448 Bayreuth, Germany. [Liu, Shibin] Chengdu Univ Technol, Inst Ecol Environm, Chengdu 610059, Peoples R China. [Schneider, Dominik] Univ Goettingen, Inst Microbiol & Genet, Grisebachstr 8, D-37077 Gottingen, Germany. [Schneider, Dominik] Univ Goettingen, Goettingen Genom Lab, Grisebachstr 8, D-37077 Gottingen, Germany. [de la Haye, Tilman; Spielvogel, Sandra] Univ Kiel, Dept Soil Sci, Hermann Rodewald Str 2, D-24118 Kiel, Germany. [Miehe, Georg] Univ Marburg, Fac Geog, Deutschhausstr 10, D-35032 Marburg, Germany. [Heitkamp, Felix] Northwest German Forest Res Inst, Environm Control, Graetzelstr 2, D-37079 Gottingen, Germany. [Seeber, Elke] Senckenberg Museum Nat Hist Goerlitz, Dept Bot, D-02806 Goerlitz, Germany. [Mason-Jones, Kyle] Netherlands Inst Ecol, Dept Terr Ecol, Postbus 50, NL-6700 AB Wageningen, Netherlands. [Xu, Xingliang] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. [Xu, Xingliang; Dorji, Tsechoe] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Huanming, Yang] Beijing Genom Inst, BGI Pk 21 Hongan 3rd St, Shenzhen 518083, Peoples R China. [Xu, Jianchu] Chinese Acad Sci, Kunming Inst Bot, Ctr Mt Futures, Kunming 650201, Yunnan, Peoples R China. [Dorji, Tsechoe] Chinese Acad Sci, Inst Tibetan Plateau Res, 16 Lincui Rd, Beijing 100101, Peoples R China. [Gube, Matthias] Univ Goettingen, Soil Sci Temperate Ecosyst, Buesgenweg 2, D-37077 Gottingen, Germany. [Norf, Helge] Helmholtz Ctr Environm Res GmbH UFZ, Dept River Ecol, Dept Aquat Ecosyst Anal & Management, Brueckstr 3a, D-39114 Magdeburg, Germany. [Meier, Jutta] Univ Koblenz Landau, Inst Integrated Nat Sci, Univ Str 1, D-56070 Koblenz, Germany. [Guggenberger, Georg] Leibniz Univ Hannover, Inst Soil Sci, Herrenhauser Str 2, D-30419 Hannover, Germany. [Kuzyakov, Yakov] Univ Goettingen, Agr Soil Sci, Buesgenweg 2, D-37077 Gottingen, Germany. RP Spielvogel, S (通讯作者)，Univ Kiel, Dept Soil Sci, Hermann Rodewald Str 2, D-24118 Kiel, Germany. EM s.spielvogel@soils.uni-kiel.de TC 9 Z9 9 PD MAY 13 PY 2022 VL 13 IS 1 AR 2681 DI 10.1038/s41467-022-30047-7 UT WOS:000795204200008 DA 2023-03-23 ER PT J AU Li, YJ Chen, KL Liu, ZF Cao, GC AF Li, Yuejin Chen, Kelong Liu, Zhifeng Cao, Guangchao TI Short-term impacts of trampling on selected soil and vegetation properties of alpine grassland in Qilian Mountain National Park, China SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Understanding the impacts of human trampling on ecological environment is necessary for the utilization and management of recreational areas. Qilian Mountain National Park is one of the first pilot areas of the national park system in China, which is also the most popular tourist destinations suitable for hiking and camping. However, there have been very few studies on human trampling in the Qilian Mountains region. We conducted a controlled trampling experiment to explore the short-term impacts of different trampling intensities (0, 50, 200, 500, and 1000 passes) on soil and vegetation in a grassland in the park. At 0-5, 5-10 and 10-20 cm soil depth, some selected soil properties were measured. Human trampling had negative impacts on surface soil properties, aboveground plant cover and height in the study area. At 0-5 cm soil depth, compared to the control site, bulk density, soil organic matter and soil penetration resistance respectively increased from 0.66 to 0.79 g/cm3, 5.5-6.5% and 9.64-13.7 kg/cm2 after 1000 passes. Soil saturated hydraulic conductivity, water holding capacity and total porosity decreased from 0.29 to 0.23 mm/min, 31.62-24.07% and 46.22-34.67%, respectively. Soil properties were degraded both on the topsoil(0-5 cm) and midsoil(5-10 cm), with the greatest degradation occurring at 1000 passes, followed by 500 passes. The total vegetation cover and mean vegetation height decreased significantly with increasing trampling intensities. After different passes, the relative vegetation cover and height showed a curvilinear decrease. A reasonable threshold of visitors should be controlled between 500 and 1000 passes to ensure the quality of the landscape. Our findings suggest that human trampling of highly sensitive and fragile alpine grasslands has a significant impact and may further impede their function. Therefore, it is urgent to protect the ecological environment of alpine grasslands. C1 [Li, Yuejin; Chen, Kelong; Cao, Guangchao] Qinghai Normal Univ, Coll Geog Sci, Qinghai Prov Key Lab Phys Geog & Environm Proc, Xining 810008, Peoples R China. [Li, Yuejin; Chen, Kelong; Cao, Guangchao] Qinghai Normal Univ, Key Lab Tibetan Plateau Land Surface Proc & Ecol C, Minist Educ, Xining 810008, Peoples R China. [Li, Yuejin; Chen, Kelong; Cao, Guangchao] Peoples Govt Qinghai Prov & Beijing Normal Univ, Acad Plateau Sci & Sustainabil, Xining 810008, Peoples R China. [Li, Yuejin] Jiangsu Univ Technol, Fac Humanities & Social Sci, Changzhou 213001, Peoples R China. [Liu, Zhifeng] Beijing Normal Univ, Fac Geog Sci, Beijing 100875, Peoples R China. RP Cao, GC (通讯作者)，Qinghai Normal Univ, Key Lab Tibetan Plateau Land Surface Proc & Ecol C, Minist Educ, Xining 810008, Peoples R China. EM tourtool@163.com; ckl7813@163.com; zhifeng.liu@bnu.edu.cn; caoguangchao@qhnu.edu.cn TC 1 Z9 1 PD AUG PY 2022 VL 36 AR e02148 DI 10.1016/j.gecco.2022.e02148 EA MAY 2022 UT WOS:000799042300002 DA 2023-03-23 ER PT J AU Cong, J Cong, W Lu, H Zhang, YG AF Cong, Jing Cong, Wei Lu, Hui Zhang, Yuguang TI Distinct Elevational Patterns and Their Linkages of Soil Bacteria and Plant Community in An Alpine Meadow of the Qinghai-Tibetan Plateau SO MICROORGANISMS DT Article AB Soil microbes play important roles in determining plant community composition and terrestrial ecosystem functions, as well as the direction and extent of terrestrial ecosystem feedback to environmental changes. Understanding the distribution patterns of plant and soil microbiota along elevation gradients is necessary to shed light on important ecosystem functions. In this study, soil bacteria along an elevation gradient in an alpine meadow ecosystem of the Qinghai-Tibetan Plateau were investigated using Illumina sequencing and GeoChip technologies. The community structure of the soil bacteria and plants presented a continuous trend along the elevation gradient, and their alpha diversity displayed different distribution patterns; however, there were no linkages between them. Beta diversity of the soil bacteria and plants was significantly influenced by elevational distance changes (p < 0.05). Functional gene categories involved in nitrogen and phosphorus cycling had faster changes than those involved in carbon degradation, and functional genes involved in labile carbon degradation also had faster variations than those involved in recalcitrant carbon degradation with elevational changes. According to Pearson's correlation, partial Mantel test analysis, and canonical correspondence analysis, soil pH and mean annual precipitation were important environmental variables in influencing soil bacterial diversity. Soil bacterial diversity and plant diversity had different distribution patterns along the elevation gradient. C1 [Cong, Jing] Qingdao Univ Sci Technol, Coll Marine Sci & Biol Engn, Qingdao 266042, Peoples R China. [Cong, Wei; Lu, Hui; Zhang, Yuguang] Chinese Acad Forestry, Inst Forest Ecol Environm & Protect, Beijing 100091, Peoples R China. [Cong, Wei; Lu, Hui; Zhang, Yuguang] State Forestry Adm, Key Lab Biol Conservat, Beijing 100091, Peoples R China. RP Zhang, YG (通讯作者)，Chinese Acad Forestry, Inst Forest Ecol Environm & Protect, Beijing 100091, Peoples R China.; Zhang, YG (通讯作者)，State Forestry Adm, Key Lab Biol Conservat, Beijing 100091, Peoples R China. EM yqdh77@163.com; cong0915wei@163.com; susanluhui@163.com; yugzhang@sina.com.cn TC 0 Z9 0 PD MAY PY 2022 VL 10 IS 5 AR 1049 DI 10.3390/microorganisms10051049 UT WOS:000802394600001 DA 2023-03-23 ER PT J AU Wang, HW Qi, Y Zhang, J Zhang, JL Yang, R Guo, JY Luo, DL Wu, JC Zhou, SM AF Wang, Hongwei Qi, Yuan Zhang, Juan Zhang, Jinlong Yang, Rui Guo, Junyu Luo, Dongliang Wu, Jichun Zhou, Shengming TI Influence of Open-Pit Coal Mining on Ground Surface Deformation of Permafrost in the Muli Region in the Qinghai-Tibet Plateau, China SO REMOTE SENSING DT Article AB The Qinghai-Tibet Plateau (QTP) is the largest mid-to low latitude and high-altitude permafrost. Open-pit coal mining and other activities have caused serious damage to the alpine ecological environment and have accelerated the degradation of permafrost on the QTP. In this study, the influence of open-pit coal mining on the time series ground surface deformation of the permafrost in the Muli region of the QTP was analyzed from 19 January 2018 to 22 December 2020 based on Landsat, Gaofen, and Sentinel remote sensing data. The primary methods include human-computer interactive visual interpretation and the small baseline subsets interferometric synthetic aperture radar (SBAS-InSAR) method. The results showed that the spatial distribution of displacement velocity exhibits a considerably different pattern in the Muli region. Alpine meadow is the main land use/land cover (LULC) in the Muli region, and the surface displacement was mainly subsidence. The surface subsidence trend in alpine marsh meadows was obvious, with a subsidence displacement velocity of 10-30 mm/a. Under the influence of changes in temperature, the permafrost surface displacement was characteristics of regular thaw subsidence and freeze uplift. Surface deformation of the mining area is relatively severe, with maximum uplift displacement velocity of 74.31 mm/a and maximum subsidence displacement velocity of 167.51 mm/a. Open-pit coal mining had resulted in the destruction of 48.73 km(2) of natural landscape in the Muli region. Mining development in the Muli region had increased the soil moisture of the alpine marsh meadow around the mining area, resulting in considerable cumulative displacement near the mining area and the acceleration of permafrost degradation. C1 [Wang, Hongwei; Qi, Yuan; Zhang, Juan; Zhang, Jinlong; Yang, Rui; Guo, Junyu; Zhou, Shengming] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou 730000, Peoples R China. [Wang, Hongwei] Northeast Forestry Univ, Sch Civil Engn, Harbin 150040, Peoples R China. [Luo, Dongliang; Wu, Jichun] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. RP Qi, Y (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou 730000, Peoples R China. EM wanghw@lzb.ac.cn; qiyuan@lzb.ac.cn; westgfdc@lzb.ac.cn; zjinlong@lzb.ac.cn; yangrui@lzb.ac.cn; guojunyu@nieer.ac.cn; luodongliang@lzb.ac.cn; wujichun@lzb.ac.cn; zhoushengming@nieer.ac.cn TC 2 Z9 2 PD MAY PY 2022 VL 14 IS 10 AR 2352 DI 10.3390/rs14102352 UT WOS:000803494100001 DA 2023-03-23 ER PT J AU Wei, YQ Lu, HY Wang, JN Wang, XF Sun, J AF Wei, Yanqiang Lu, Haiyan Wang, Jinniu Wang, Xufeng Sun, Jian TI Dual Influence of Climate Change and Anthropogenic Activities on the Spatiotemporal Vegetation Dynamics Over the Qinghai-Tibetan Plateau From 1981 to 2015 SO EARTHS FUTURE DT Article AB Climate change and human activities have already caused degradation in a large fraction of vegetation on the Qinghai-Tibetan Plateau (QTP). Many studies report that climate variability instead of overgrazing has been the primary cause for large-scale vegetation cover changes on the QTP, for example, Lehnert et al., 2016, . However, it remains unclear how human activities (mainly livestock grazing) regulate vegetation dynamics under climate change. This paper takes the AVHRR/GIMMS Normalized Difference Vegetation Index (NDVI) as an indicator to analyze the growth status of vegetation zones in the QTP, which has highly sensitive to climate change. The spatiotemporal dynamics of vegetation growth between 1981 and 2015 were analyzed. The dual effects of climate change and human activities were examined by correlation analyses of data from 87 meteorological stations and economic statistical data of the QTP. Results show that: (a) The vegetation in central and southwestern QTP with high altitudes was improving due to the warm-humid climate trend. An increase in temperature and a reduction in the harsh frigid climate at high altitudes due to global warming has resulted in expansions of the vegetated areas, with the NDVI showing a concordant increase. (b) The degraded areas were mainly confined to the northern and eastern QTP, which have high human and livestock population densities. In comparison to gently changing climate regimes, anthropogenic activities such as chronic concentration of population and livestock in the valleys with a less harsh climate exerts a much stronger pressure on vegetation. The study indicates that the anthropogenic pressures are much more intensive than the impact of climate change and are critical for the conservation and sustainable management of the QTP vegetation. C1 [Wei, Yanqiang; Wang, Xufeng] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou, Peoples R China. [Lu, Haiyan] Lanzhou Univ Finance & Econ, Sch Accountancy, Lanzhou, Peoples R China. [Lu, Haiyan] Lanzhou Univ, Sch Econ, Lanzhou, Peoples R China. [Wang, Jinniu] Chinese Acad Sci, Chengdu Inst Biol, Chengdu, Peoples R China. [Wang, Jinniu] Chinese Acad Sci, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu, Peoples R China. [Sun, Jian] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing, Peoples R China. RP Wei, YQ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou, Peoples R China. EM weiyq@lzb.ac.cn TC 9 Z9 10 PD MAY PY 2022 VL 10 IS 5 AR e2021EF002566 DI 10.1029/2021EF002566 UT WOS:000798080000001 DA 2023-03-23 ER PT J AU Zhao, ZY Zhang, YL Sun, SQ Li, T Lu, YH Jiang, W Wu, X AF Zhao, Zhengyuan Zhang, Yunlong Sun, Siqi Li, Ting Lu, Yihe Jiang, Wei Wu, Xing TI Spatiotemporal Variations in Grassland Vulnerability on the Qinghai-Tibet Plateau Based on a Comprehensive Framework SO SUSTAINABILITY DT Article AB Grasslands are globally important for providing essential ecosystem services and maintaining ecological security. Monitoring and assessing grassland vulnerability are critical for developing long-term grassland management policies and strategies. The grassland vulnerability on the Qinghai-Tibet Plateau (QTP) is considered high, but its spatial and temporal variations in response to human activities and climate change are not well understood. In this study, a comprehensive grassland vulnerability index (GVI), which includes natural factors (VNF), environmental disturbances (VED), and socioeconomic impacts (VSI), was developed by using the analytic hierarchy process (AHP), principal component analysis (PCA), and environmental vulnerability distance index (EVDI). Our results showed that the spatial distribution of GVI had obvious heterogeneity, decreasing from northwest to southeast; the regions with serious and extreme vulnerability were mainly concentrated in the north-western alpine steppe and desert steppe. From 2000 to 2018, GVI decreased from 0.61 in 2000 to 0.60 in 2010 and then to 0.59 in 2018, demonstrating a healthy tendency. The normalized difference vegetation index (NDVI), land desertification, and population were the factors that had the most significant impact on VNF, VED, and VSI, respectively. The global Moran's I index of grassland vulnerability was greater than 0, with a significant positive spatial correlation. The number of High-High and Low-Low units decreased, indicating that the High-High and Low-Low cluster regions tended to be discrete. Moreover, our results suggest that understanding the variations in grassland vulnerability on the QTP is important for regional sustainable development in the context of intensified climate change and human disturbances. C1 [Zhao, Zhengyuan; Zhang, Yunlong; Sun, Siqi; Li, Ting; Lu, Yihe; Jiang, Wei; Wu, Xing] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China. [Zhao, Zhengyuan; Sun, Siqi; Li, Ting; Lu, Yihe; Wu, Xing] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. RP Wu, X (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China.; Wu, X (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM zhaozhengyuan1999@163.com; yunlongzhang@rcees.ac.cn; m15510761127@163.com; 18811600716@163.com; lyh@rcees.ac.cn; weijiang@rcees.ac.cn; xingwu@rcees.ac.cn TC 1 Z9 1 PD MAY PY 2022 VL 14 IS 9 AR 4912 DI 10.3390/su14094912 UT WOS:000795296300001 DA 2023-03-23 ER PT J AU Zhao, YF Wang, X Li, J Xiao, JJ Hao, ZG Wang, KC Jiang, SL Zhou, XH Liu, HY AF Zhao, YunFei Wang, Xia Li, Jia Xiao, JinJin Hao, ZhiGuo Wang, KaiChang Jiang, SiLong Zhou, XiaoHe Liu, HuiYing TI Variation of delta C-13 and soil organic carbon under different precipitation gradients in alpine grassland on the Qinghai-Tibetan Plateau SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Purpose Soil organic carbon (SOC) dynamics strongly affect the terrestrial carbon balance, and stable isotopic measurements provide detailed information about SOC cycling. However, the response of delta C-13 and SOC to climatic factors is still not well known in high alpine regions. Methods In this study, soil delta C-13 and SOC in vertical soil profiles were analysed at alpine grassland sites along four precipitation gradients (350-400, 450-500, 550-600, and 650-700 mm) on the eastern Qinghai-Tibetan Plateau. The p value is defined by the slope of the linear regression relating soil delta C-13 to the logarithm of SOC, and the higher p values represent slower SOC turnover. Results The SOC concentration tended to decline with increasing soil depth from 0 to 40 cm, while delta C-13 was enriched in alpine grassland on the eastern Qinghai-Tibetan Plateau. The delta C-13 values in the 650-700-mm class were relatively depleted compared with other precipitation classes. Redundancy analysis (RDA) showed that altitude was the most important factor-explaining 20.9% of the variation in C-13 in surface soil (0-10 cm), followed by mean annual air temperature (MAT) (17.1%) and mean annual precipitation (MAP) (16.9%). MAT and altitude were the main factors controlling delta C-13 and p values. MAP did not significantly affect SOC distribution, but lower delta C-13 and p values occurred with higher precipitation. Correlations between SOC content and MAT increased significantly after removing relationships with MAP. Conclusions The results indicate that faster SOC decomposition may not necessarily lead to SOC losses on the eastern Tibetan Plateau given current conditions. Future research should consider the effects of interactions between warmer and wetter conditions (predicted under climate change) on SOC content and turnover. C1 [Zhao, YunFei; Wang, Xia; Li, Jia; Xiao, JinJin; Hao, ZhiGuo; Wang, KaiChang; Jiang, SiLong; Zhou, XiaoHe; Liu, HuiYing] Lanzhou Univ, Coll Earth & Environm Sci, Gansu Key Lab Environm Pollut Predict & Control, Lanzhou 730000, Peoples R China. [Wang, Xia] Minist Nat Resources, Key Lab Strateg Mineral Resources Upper Yellow Ri, Lanzhou 730000, Peoples R China. [Zhao, YunFei; Li, Jia] Minist Educ, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Peoples R China. RP Wang, X (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, Gansu Key Lab Environm Pollut Predict & Control, Lanzhou 730000, Peoples R China.; Wang, X (通讯作者)，Minist Nat Resources, Key Lab Strateg Mineral Resources Upper Yellow Ri, Lanzhou 730000, Peoples R China. EM wangxia@lzu.edu.cn TC 1 Z9 1 PD AUG PY 2022 VL 22 IS 8 BP 2219 EP 2228 DI 10.1007/s11368-022-03223-x EA APR 2022 UT WOS:000788927100002 DA 2023-03-23 ER PT J AU Ma, J Qin, JR Ma, HB Zhou, Y Shen, Y Xie, YZ Xu, DM AF Ma, Jing Qin, Jianrong Ma, Hongbin Zhou, Yao Shen, Yan Xie, Yingzhong Xu, Dongmei TI Soil characteristic changes and quality evaluation of degraded desert steppe in arid windy sandy areas SO PEERJ DT Article AB Grassland degradation has become a serious problem in some areas, making it necessary to quantitatively evaluate this process and its related factors. The study area was the arid windy sandy area in eastern Ningxia. The purpose of this study was to explore how soil properties and quality change during the process of grassland degradation in arid windy sandy areas. We looked at undegraded, lightly degraded, moderately degraded, and severely degraded desert steppe to study the physical, chemical, and biological changes at 0-5 cm, 5-15 cm, and 15-30 cm soil depths at different degradation degrees. We also analyzed the correlations across soil factors, established the minimum data set, and used the soil quality index (SQI) to evaluate the soil quality of grassland at different degradation degrees. The results showed that with grassland degradation, the soil bulk density increased; the soil clay, moisture, organic matter, total nitrogen, and available potassium content decreased; and the number of soil bacteria, actinomycetes, and fungi, as well as the activity of urease, polyphenol oxidase, protease, phosphatase, and sucrase, decreased. As soil depth increased, soil bulk density increased; the soil moisture, organic matter, available potassium, and available phosphorus content decreased; and soil microorganisms accumulated in the upper soil of undegraded, lightly, and moderately degraded grassland. There was also a positive correlation among the soil clay content, moisture content, organic matter content, total nitrogen content, available potassium content, microorganism quantity, and enzyme activity, while soil bulk density was negatively correlated with the above factors. The minimum data set for the soil quality evaluation of the degraded desert steppe was comprised of soil organic matter content, soil total nitrogen content, soil available phosphorus content, and phosphatase activity. Based on the minimum data set, we calculated the SQI of the grassland at different degradation degrees and found that the ranking based on overall soil quality was undegraded >lightly degraded >moderately degraded >severely degraded grassland. The results showed that the degradation of desert steppe in arid windy sandy areas had relatively consistent effects on the physical, chemical, and biological traits of the soil. The minimum data set can be used to replace the total data set when evaluating the soil quality of the desert steppe at different degrees of degradation. C1 [Ma, Jing; Ma, Hongbin; Zhou, Yao; Shen, Yan; Xie, Yingzhong; Xu, Dongmei] Ningxia Univ, Sch Agr, Yinchuan, Ningxia, Peoples R China. [Ma, Jing] Ningxia Acad Agr & Forestry Sci, Agr Econ & Informat Technol Res Inst, Yinchuan, Ningxia, Peoples R China. [Qin, Jianrong] Chengdu Pk City Construct & Dev Res Inst, Chengdu, Peoples R China. RP Ma, HB (通讯作者)，Ningxia Univ, Sch Agr, Yinchuan, Ningxia, Peoples R China. EM ma_hb@nxu.edu.cn TC 1 Z9 1 PD APR 28 PY 2022 VL 10 AR e13100 DI 10.7717/peerj.13100 UT WOS:000796546400002 DA 2023-03-23 ER PT J AU Peng, JL Ma, FF Quan, Q Chen, XL Wang, JS Yan, YJ Zhou, QP Niu, SL AF Peng, Jinlong Ma, Fangfang Quan, Quan Chen, Xinli Wang, Jinsong Yan, Yingjie Zhou, Qingping Niu, Shuli TI Nitrogen enrichment alters climate sensitivity of biodiversity and productivity differentially and reverses the relationship between them in an alpine meadow SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Biodiversity and productivity that highly determine ecosystem services are varying largely under global change. However, the climate sensitivity of them and their relationship are not well understood, especially in the context of increasing nitrogen (N) deposition. Here, based on a six-year N manipulation experiment in an alpine meadow, we quantified inter annual climate sensitivity of species richness (SR) and above-ground net primary productivity (ANPP) as well as SR-ANPP relationship as affected by six N addition rate (N-rate) gradients. We found that interannual variations in ANPP and SR were mainly driven by temperature instead of precipitation. In the plots without N addition, higher temperature substantially increased ANPP but reduced SR across years, thus resulting in a negative SR-ANPP relationship. However, the negative and positive responses of SR and ANPP to temperature increased and declined significantly with increasing N-rate, respectively, leading to a shift of the negative relationship between SR and ANPP into a positive one under high N-rate.Moreover, the adverse influence of drought on SR and ANPP would be aggravated by N fertilization, as indicated by the increased positive effect of precipitation on them under N enrichment. Our findings indicate that climate sensitivity of productivity and biodiversity may be misestimated if the impact of N deposition is not considered, and the importance of biodiversity to maintain productivity would enhance as N deposition increases. This study provides a new insight to explain variation of biodiversity-productivity relationship along with environmental changes. C1 [Peng, Jinlong; Ma, Fangfang; Quan, Quan; Wang, Jinsong; Yan, Yingjie; Niu, Shuli] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, 11A,Datun Rd, Beijing 100101, Peoples R China. [Peng, Jinlong; Ma, Fangfang; Quan, Quan; Yan, Yingjie; Niu, Shuli] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Chen, Xinli] Lakehead Univ, Fac Nat Resources Management, Thunder Bay, ON, Canada. [Zhou, Qingping] Southwest Univ Nationalities, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. RP Niu, SL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, 11A,Datun Rd, Beijing 100101, Peoples R China. EM sniu@igsnrr.ac.cn TC 0 Z9 0 PD AUG 20 PY 2022 VL 835 AR 155418 DI 10.1016/j.scitotenv.2022.155418 EA APR 2022 UT WOS:000796616500012 DA 2023-03-23 ER PT J AU Wang, HY Wu, JQ Li, G Yan, LJ Wei, XX Ma, WW AF Wang, Haiyan Wu, Jiangqi Li, Guang Yan, Lijuan Wei, Xingxing Ma, Weiwei TI Effects of Simulated Nitrogen Deposition on Soil Active Carbon Fractions in a Wet Meadow in the Qinghai-Tibet Plateau SO JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION DT Article AB Purpose Atmospheric nitrogen (N) deposition may break the original carbon (C) and N balance in the ecosystems. The effects of N deposition on terrestrial ecosystems, especially in Qinghai-Tibet Plateau (QTP) regions have become a major research topic. However, the responses of soil active carbon fractions to N deposition in the QTP remain unknown. Methods We conducted a 2-year field experiment with four N addition levels (0, 5, 10, and 15 g m(-2) a(-1)) in the QTP and collected soil samples from three soil layers (0-10, 10-20, and 20-40 cm) to study how N deposition affects soil carbon components (soil organic carbon, SOC; microbial biomass carbon, MBC; dissolved organic carbon, DOC) and their relationships. Results N deposition significantly increased the SOC content in the 0-10-cm layer (P < 0.01), MBC content firstly increased, and then decreased with the increase of N deposition, the MBC content in the 0-10-cm layer changed the most significantly, and the DOC content decreased significantly with the increase of N addition level. The SOC, DOC, and MBC content had obvious seasonal variation, and the variation trend was not consistent. Pearson correlation analysis indicated that soil bulk density (BD) and aboveground biomass were significantly related to different SOC fractions. Conclusions Our results showed that atmospheric N deposition reduces the active carbon content by affecting aboveground biomass, resulting in the increase of SOC storage. Therefore, N deposition may negatively affect the active organic carbon and may change the C pool function of the wet meadow soil on the QTP. C1 [Wang, Haiyan; Wu, Jiangqi; Li, Guang; Wei, Xingxing; Ma, Weiwei] Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China. [Yan, Lijuan] Gansu Agr Univ, Coll Agron, Lanzhou 730070, Peoples R China. RP Li, G (通讯作者)，Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China. EM liggsau@foxmail.com TC 0 Z9 0 PD SEP PY 2022 VL 22 IS 3 BP 2943 EP 2954 DI 10.1007/s42729-022-00858-0 EA APR 2022 UT WOS:000794901200001 DA 2023-03-23 ER PT J AU Hua, T Zhao, WW Pereira, P AF Hua, Ting Zhao, Wenwu Pereira, Paulo TI Opinionated Views on Grassland Restoration Programs on the Qinghai-Tibetan Plateau SO FRONTIERS IN PLANT SCIENCE DT Article C1 [Hua, Ting; Zhao, Wenwu] Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing, Peoples R China. [Hua, Ting; Zhao, Wenwu] Beijing Normal Univ, Fac Geog Sci, Inst Land Surface Syst & Sustainable Dev, Beijing, Peoples R China. [Pereira, Paulo] Mykolas Romeris Univ, Environm Management Ctr, Vilnius, Lithuania. RP Zhao, WW (通讯作者)，Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing, Peoples R China.; Zhao, WW (通讯作者)，Beijing Normal Univ, Fac Geog Sci, Inst Land Surface Syst & Sustainable Dev, Beijing, Peoples R China. EM zhaoww@bnu.edu.cn TC 5 Z9 5 PD APR 26 PY 2022 VL 13 AR 861200 DI 10.3389/fpls.2022.861200 UT WOS:000886907300001 DA 2023-03-23 ER PT J AU Wu, MH Xue, K Wei, PJ Jia, YL Zhang, Y Chen, SY AF Wu, Ming-Hui Xue, Kai Wei, Pei-Jie Jia, Ying-Lan Zhang, Yu Chen, Sheng-Yun TI Soil microbial distribution and assembly are related to vegetation biomass in the alpine permafrost regions of the Qinghai-Tibet Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB It is generally believed that there is a vegetation succession sequence from alpine marsh meadow to desert in the alpine ecosystem of the Qinghai-Tibet Plateau. However, we still have a limited understanding about distribution patterns and community assemblies of microorganisms' response to such vegetation changes. Hence, across a gradient represented by three types of alpine vegetation from swamp meadow to meadow to steppe, the soil bacterial, fungal and archaeal diversity was evaluated and then associated with their assembly processes, and glacier foreland vegetation was also surveyed as a case out of this gradient. Vegetation biomass was found to decrease significantly along the vegetation gradient. In contrast to irregular shifts in alpha diversity, bacterial and fungal beta diversities that were dominated by species replacement components (71.07-9.08%) significantly increased with the decreasing gradient in vegetation biomass (P < 0.05). These trends of increase were also found in the extent of stochastic bacterial and fungal assembly. Moreover, an increase in microbial beta diversity but a decrease in beta nearest taxon index were observed along with increased discrepancy in vegetation biomass (P < 0.001). Stepwise regression analyses and structural equation models suggested that vegetation biomass was the major variable that was related to microbial distribution and community assembly, and there might be associations between the dominance of species replacements and stochastic assembly. These findings enhanced our recognition of the relationship between vegetation and soil microorganisms and would facilitate the development of vegetation-microbe feedback models in alpine ecosystems. C1 [Wu, Ming-Hui; Wei, Pei-Jie; Jia, Ying-Lan; Chen, Sheng-Yun] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Natl Field Sci Observat & Res Stn Yulong Snow Mt, State Key Lab Cryospher Sci,Cryosphere & Ecoenvir, Lanzhou 730000, Gansu, Peoples R China. [Wu, Ming-Hui; Xue, Kai; Wei, Pei-Jie; Jia, Ying-Lan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Yu; Chen, Sheng-Yun] Long Term Natl Sci Res Base Qilian Mt Natl Pk, Xining 810000, Qinghai, Peoples R China. RP Chen, SY (通讯作者)，320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. EM sychen@lzb.ac.cn TC 7 Z9 8 PD AUG 15 PY 2022 VL 834 AR 155259 DI 10.1016/j.scitotenv.2022.155259 EA APR 2022 UT WOS:000832996700005 DA 2023-03-23 ER PT J AU Huang, XM Lu, XR Zhou, GY Shi, YF Zhang, DG Zhang, WJ Bai, SH AF Huang, Xiaomin Lu, Xuanrui Zhou, Guiyao Shi, Yafei Zhang, Degang Zhang, Weijian Bai, Shahla Hosseini TI How land-use change affects soil respiration in an alpine agro-pastoral ecotone SO CATENA DT Article AB Land-use change alters soil carbon (C) storage in terrestrial ecosystem through affecting soil respirations (Rs). However, the long-term effects of land-use change on Rs are poorly understood. We undertook a field experiment to examine the effects of long-term land-use change on Rs. The land-use types included grazed grassland (GGL), enclosed grassland (EGL), continuous cropland (CCL), rotation cropland (RCL) and abandoned cropland (ACL) in an alpine agro-pastoral ecotone in Qinghai-Tibetan Plateau in China. Our results showed that the accumulative Rs was shown a decreasing order of EGL > CCL > RCL > GGL > ACL, with the highest value of 12.2 t CO2 ha-1 and the lowest value of 5.3 t CO2 ha-1. Soil bulk density, moisture, pH and C/N ratio were the key factors regulating Rs with land-use change in Tianzhu alpine agro-pastoral ecotone. Soil pH and C/N ratio regulated Rs indirectly by affecting bacterial diversity, while soil moisture had indirect impacts on Rs mainly by regulating microbial biomass. The net effects of soil bulk density on Rs was mainly through the direct pathway. Considering the soil C stocks showed an increasing order of ACL < RCL < CCL < GGL < EGL, even though ACL had the lowest Rs, grasslands probably the favorable land-use type in alpine agro-pastoral ecotone. Our findings highlight the importance of the land-use change on Rs, which may need to be incorporated into regional and global models for better predicting C-climate feedbacks. C1 [Huang, Xiaomin; Lu, Xuanrui] Agr Coll Yangzhou Univ, Jiangsu Key Lab Crop Genet & Physiol, Jiangsu Key Lab Crop Cultivat & Physiol, Yangzhou 225009, Peoples R China. [Huang, Xiaomin; Lu, Xuanrui] Yangzhou Univ, Jiangsu Coinnovat Ctr Modern Prod Technol Grain Cr, Yangzhou 225009, Peoples R China. [Zhou, Guiyao] East China Normal Univ, Sch Ecol & Environm Sci, Zhejiang Tiantong Forest Ecosyst Natl Observat & R, Shanghai 200062, Peoples R China. [Shi, Yafei] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Shapotou Desert Res & Expt Stn, Lanzhou 730000, Peoples R China. [Zhang, Degang] Gansu Agr Univ, Lanzhou 730070, Peoples R China. [Zhang, Weijian] Chinese Acad Agr Sci, Inst Crop Sci, Key Lab Crop Physiol & Ecol, Minist Agr, Beijing 100081, Peoples R China. [Bai, Shahla Hosseini] Griffith Univ, Ctr Planetary Hlth & Food Secur, Sch Environm & Sci, Nathan, Qld 4111, Australia. RP Huang, XM (通讯作者)，Agr Coll Yangzhou Univ, Jiangsu Key Lab Crop Genet & Physiol, Jiangsu Key Lab Crop Cultivat & Physiol, Yangzhou 225009, Peoples R China.; Zhang, WJ (通讯作者)，Chinese Acad Agr Sci, Inst Crop Sci, Key Lab Crop Physiol & Ecol, Minist Agr, Beijing 100081, Peoples R China. EM hxm2020@yzu.edu.cn; zhangweijian@caas.cn TC 2 Z9 2 PD JUL PY 2022 VL 214 AR 106291 DI 10.1016/j.catena.2022.106291 EA APR 2022 UT WOS:000797993300001 DA 2023-03-23 ER PT J AU Nie, XQ Wang, D Ren, LN Ma, KL Chen, YZ Yang, LC Du, YG Zhou, GY AF Nie, Xiuqing Wang, Dong Ren, Lining Ma, Kaili Chen, Yongzhe Yang, Lucun Du, Yangong Zhou, Guoying TI Distribution Characteristics and Controlling Factors of Soil Total Nitrogen: Phosphorus Ratio Across the Northeast Tibetan Plateau Shrublands SO FRONTIERS IN PLANT SCIENCE DT Article AB Nitrogen (N) and phosphorus (P) stoichiometry have significant effects on nutrient cycles in terrestrial ecosystems. However, our understanding of the patterns and the driving factors of soil N:P ratios in the Tibetan Plateau shrublands remains limited. Our study aimed to quantify the distribution of soil N:P ratio and its controlling factors based on soil, plant, and climate factors from 59 sites in shrublands across the northeast Tibetan Plateau. The kriging interpolation method was used to quantify the soil N:P distribution. Spatially, the soil N:P ratio was higher in the south than in the north and lower in the west than in the east. The soil N:P ratio in the northeast Tibetan Plateau shrublands was mainly explained by edaphic factors, which also played an important role in regulating the effects of plant and climate factors on soil N:P ratios. Mean annual precipitation, instead of mean annual temperature, significantly controlled the soil N:P ratios, and its effect on the pattern of soil N:P ratios differed between alpine shrublands and desert shrublands. The N:P ratios of different organs in shrublands also played different roles in shaping the soil N:P ratios in alpine and desert shrublands. These results provide support for the hypothesis that edaphic factors were the dominant drivers of spatial variation in soil N:P ratios across the northeast Tibetan Plateau shrublands, and our study contributes to a deeper understanding of biogeochemical cycling at high altitudes. C1 [Nie, Xiuqing; Wang, Dong; Chen, Yongzhe] Chinese Acad Forestry, Ecol & Nat Conservat Inst, Key Lab Forest Ecol Environm, Natl Forestry Grassland Adm Ecol, Beijing, Peoples R China. [Nie, Xiuqing; Yang, Lucun; Du, Yangong; Zhou, Guoying] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Peoples R China. [Ren, Lining] Chinese Acad Forestry, Res Inst Forestry, Beijing, Peoples R China. [Ma, Kaili] Monitoring & Evaluat Ctr Qinghai Natl Pk, Xining, Peoples R China. RP Nie, XQ; Wang, D (通讯作者)，Chinese Acad Forestry, Ecol & Nat Conservat Inst, Key Lab Forest Ecol Environm, Natl Forestry Grassland Adm Ecol, Beijing, Peoples R China.; Nie, XQ; Zhou, GY (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Peoples R China. EM niexiuqing@caf.ac.cn; dwang@caf.ac.cn; zhougy@nwipb.cas.cn TC 2 Z9 2 PD APR 12 PY 2022 VL 13 AR 825817 DI 10.3389/fpls.2022.825817 UT WOS:000791686900001 DA 2023-03-23 ER PT J AU Huang, Q Zeng, K Chen, DM Li, Q Gu, R Bai, YF Sun, FD Zhou, JQ Gao, WC Ran, ZY Peng, Y Zhao, JM Ma, X Bai, SQ Liu, L AF Huang, Qian Zeng, Kai Chen, Dongming Li, Qi Gu, Rui Bai, Yanfu Sun, Feida Zhou, Jiqiong Gao, Wuchao Ran, Zhuoya Peng, Yan Zhao, Junming Ma, Xiao Bai, Shiqie Liu, Lin TI Selecting suitable shrub and herb species to revegetation from the perspective of root exudates: An implication for ecological restoration of desertification in an alpine meadow of the eastern Tibetan Plateau SO RHIZOSPHERE DT Article AB Till now, the lack of research regard to root exudates is still serious in the restoration process of desertification alpine meadow in the eastern Tibetan plateau, although recovery of desertification land resulted from overgrazing and climate change is known to be shaped by the rhizosphere. Therefore, we measured root carbon (C) exudate rates of Kengyilia rigidula (Keng) S. L. Chen., Rhodiola kirilowii (Regel) Maxim., Elymus nutans Griseb., Hippophae rhamnoides L. and Salix cupularis Rehd. by sampling root exudates in situ in a desertification alpine meadow, as well as determined the volatile components using GC-MS. The results showed that 1) Root C exudate rates were as follows: R. kirilowii > K. rigidula > E. nutans > S. cupularis > H. rhamnoides, and R. kirilowii was significantly higher than H. rhamnoides (p < 0.05). 2) Common volatile substances of the five plants mainly contained hydrocarbons (above 13.16%), esters (above 11.83%) and phenols (above 6.27%), and the relative amounts of hydrocarbons and phenols were the highest in R. kirilowii respectively, while esters were the highest in S. cupularis among the five plant species. Thereinto, 2-hydroxy-1-(hydroxymethyl) ethyl ester was the highest content in R. kirilowii while 2,4-di-tert-butyl phenol was the highest content in S. cupularis. 3) As the specific allelochemical components of herbs and shrubs, heptadecane was the highest content in R. kirilowii among the three herb species while pentacosane was relatively high content in S. cupularis between the two shrubs, and the relative amount of palmitic acid in R. kirilowii was about twice that in H. rhamnoides and S. cupularis, accounting for 1.64%. Collectively, our results suggest that S. cupularis and R. kirilowii should be regarded as the better choice of pioneer plant species to be applied to ecological restoration of desertification alpine meadow. C1 [Huang, Qian; Zeng, Kai; Chen, Dongming; Li, Qi; Bai, Yanfu; Sun, Feida; Zhou, Jiqiong; Gao, Wuchao; Ran, Zhuoya; Peng, Yan; Zhao, Junming; Ma, Xiao; Liu, Lin] Sichuan Agr Univ, Coll Grassland Sci & Technol, 211 Huimin Rd, Chengdu 611130, Peoples R China. [Zeng, Kai] Sun Yat Sen Univ, Coll Agr, Guangzhou 510275, Guangdong, Peoples R China. [Li, Qi] Sichuan Grassland Gen Work Stn, Chengdu 610081, Sichuan, Peoples R China. [Gu, Rui] Chengdu Univ Tradit Chinese Med, Coll Med, Chengdu 611137, Sichuan, Peoples R China. [Bai, Shiqie] Sichuan Acad Grassland Sci, Chengdu 611731, Sichuan, Peoples R China. RP Liu, L (通讯作者)，Sichuan Agr Univ, Coll Grassland Sci & Technol, 211 Huimin Rd, Chengdu 611130, Peoples R China. EM liulinsky@126.com TC 0 Z9 0 PD JUN PY 2022 VL 22 AR 100506 DI 10.1016/j.rhisph.2022.100506 EA APR 2022 UT WOS:000832791600009 DA 2023-03-23 ER PT J AU Wang, DJ Zhou, HK Zuo, J Chen, P She, YD Yao, BQ Dong, SK Wu, JS Li, F Njoroge, DM Shi, GX Mao, XF Ma, L Zhang, ZH Mao, Z AF Wang, Dangjun Zhou, Huakun Zuo, Juan Chen, Peng She, Yandi Yao, Buqing Dong, Shikui Wu, Jianshuang Li, Fan Njoroge, Denis Mburu Shi, Guoxi Mao, Xufeng Ma, Li Zhang, Zhonghua Mao, Zhun TI Responses of Soil Microbial Metabolic Activity and Community Structure to Different Degraded and Restored Grassland Gradients of the Tibetan Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB Climate change and land-use disturbances are supposed to have severely affected the degraded alpine grasslands on the Tibetan Plateau. Artificial grassland establishment has been implemented as a restoration tool against grassland degradation. However, the impact of such degradation and restoration processes on soil microbial communities and soil quality is not clearly understood. Here, we aim to investigate how the dynamics of microbial community and soil quality of alpine grasslands respond to a gradient of degradation and that of restoration, respectively. We conducted a randomised experiment with four degradation stages (light, moderate, heavy, and extreme degradation) and three restoration stages (artificial restoration for 1, 5, and 10 years). We analysed the abundance and diversity of soil bacteria and fungi, and measured soil nutrients, enzymatic activity and microbial biomass. The concentration of soil nitrogen (TN), soil organic matter (OM) in heavy degraded grassland decreased significantly by 37.4 and 45.08% compared with that in light degraded grassland. TN and OM in 10-years restored grassland also increased significantly by 33.10 and 30.42% compared to that in 1-year restored grassland. Four soil enzymatic activity indicators related to microbial biomass decreased with degradation gradient and increased with recovery time (i.e., restoration gradient). Both bacterial and fungal community structure was significantly different among grassland degradation or restoration successional stages. The LEfSe analysis revealed that 29 fungal clades and 9 bacterial clades were susceptible to degraded succession, while16 fungal clades and 5 bacterial clades were susceptible to restoration succession. We conclude that soil quality (TN, OM, and enzymatic activity) deteriorated significantly in heavy degraded alpine grassland. Soil microbial community structure of alpine is profoundly impacted by both degradation and restoration processes, fungal communities are more sensitive to grassland succession than bacterial communities. Artificial grasslands can be used as an effective method of restoring degraded grassland, but the soil functions of artificial grassland, even after 10 years of recovery, cannot be restored to the original state of alpine grassland. C1 [Wang, Dangjun; Zuo, Juan; Chen, Peng; Li, Fan; Njoroge, Denis Mburu] Chinese Acad Sci, Key Lab Aquat Bot & Watershed Ecol, Wuhan Bot Garden, Wuhan, Peoples R China. [Wang, Dangjun; Zhou, Huakun; She, Yandi; Yao, Buqing; Ma, Li; Zhang, Zhonghua] Chinese Acad Sci, Key Lab Cold Reg Restorat Ecol, Northwest Inst Plateau Biol, Xining, Qinghai, Peoples R China. [Wang, Dangjun; Njoroge, Denis Mburu] Chinese Acad Sci, Sino Africa Joint Res Ctr, Wuhan, Peoples R China. [Wang, Dangjun; She, Yandi; Li, Fan; Njoroge, Denis Mburu; Ma, Li; Zhang, Zhonghua] Univ Chinese Acad Sci, Beijing, Peoples R China. [Dong, Shikui] Beijing Forestry Univ, Sch Grassland Sci, Beijing, Peoples R China. [Wu, Jianshuang] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. [Shi, Guoxi] Tianshui Normal Univ, Coll Bioengn & Biotechnol, Key Lab Utilizat Agr Solid Waste Resources, Tianshui, Peoples R China. [Mao, Xufeng] Qinghai Normal Univ, Sch Geog Sci, Xining, Peoples R China. [Mao, Zhun] Univ Montpellier, AMAP, CIRAD, CNRS,INRAE,IRD, Montpellier, France. RP Zhou, HK (通讯作者)，Chinese Acad Sci, Key Lab Cold Reg Restorat Ecol, Northwest Inst Plateau Biol, Xining, Qinghai, Peoples R China. EM hkzhou@nwipb.cas.cn TC 3 Z9 3 PD APR 8 PY 2022 VL 13 AR 770315 DI 10.3389/fpls.2022.770315 UT WOS:000792388100001 DA 2023-03-23 ER PT J AU Dai, LC Fu, RY Guo, XW Du, YG Zhang, FW Cao, GM AF Dai, Licong Fu, Ruiyu Guo, Xiaowei Du, Yangong Zhang, Fawei Cao, Guangmin TI Soil Moisture Variations in Response to Precipitation Across Different Vegetation Types on the Northeastern Qinghai-Tibet Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB An understanding of soil moisture conditions is crucial for hydrological modeling and hydrological processes. However, few studies have compared the differences between the dynamics of soil moisture content and soil moisture response to precipitation infiltration under different types of vegetation on the Qinghai-Tibet Plateau (QTP). In this study, a soil moisture sensor was used for continuous volumetric soil moisture measurements during 2015 and 2016, with the aim of exploring variations in soil moisture and its response to precipitation infiltration across two vegetation types (alpine meadow and alpine shrub). Our results showed that temporal variations in soil moisture at the surface (0-20 cm) and middle soil layers (40-60 cm) were consistent with precipitation patterns for both vegetation types. However, there was a clear lag in the soil moisture response to precipitation for the deep soil layers (80-100 cm). Soil moisture content was found to be significantly positively related to precipitation and negatively related to air temperature. Aboveground biomass was significantly negatively associated with the surface soil moisture content (0-20 cm) during the growing season. Statistically significant differences were observed between the soil water content of the surface, middle, and deep soil layers for the two vegetation types (p < 0.05). Soil moisture (19.81%) in the surface soil layer was significantly lower than that in the deep soil layer (24.75%) for alpine shrubs, and the opposite trend was observed for alpine meadows. The maximum infiltration depth of alpine shrubs was greater than that of alpine meadows under extremely high-precipitation events, which indicates that alpine shrubs might be less susceptible to surface runoff under extreme precipitation events. Furthermore, low precipitation amounts did not affect precipitation infiltration for either vegetation type, whereas the infiltration depth increased with precipitation for both vegetation types. Our results suggest that a series of small precipitation events may not have the same effect on soil moisture as a single large precipitation event that produces the equivalent total rainfall. C1 [Dai, Licong] Hainan Univ, Coll Ecol & Environm, Haikou, Hainan, Peoples R China. [Dai, Licong; Guo, Xiaowei; Du, Yangong; Zhang, Fawei; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining, Peoples R China. [Dai, Licong; Guo, Xiaowei; Du, Yangong; Zhang, Fawei; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. [Fu, Ruiyu] Hainan Acad Forestry, Haikou, Hainan, Peoples R China. RP Guo, XW (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining, Peoples R China.; Guo, XW (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. EM xwguo1206@163.com TC 3 Z9 3 PD APR 6 PY 2022 VL 13 AR 854152 DI 10.3389/fpls.2022.854152 UT WOS:000807683600001 DA 2023-03-23 ER PT J AU Yang, C Deng, W Yuan, QZ Zhang, SY AF Yang, Cai Deng, Wei Yuan, Quanzhi Zhang, Shaoyao TI Changes in Landscape Pattern and an Ecological Risk Assessment of the Changshagongma Wetland Nature Reserve SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB The Changshagongma wetlands is the Chinese National Nature Reserve were listed as a Ramsar Wetland of International Importance in 2018. Here, we examined four periods (1992, 2002, 2013, and 2020) of remote sensing image data to analyze the changes in wetland landscape patterns and the ecological risk in Changshagongma Wetland Nature Reserve over the past 30 years. The results showed that wetlands account for approximately 30% of the study area, and swamp meadows were the main type of wetland, accounting for approximately 95% of the total wetland area. In terms of landscape patterns, wetland fragmentation declined, wetland patch shapes became less complicated, and spatial connectivity increased. The landscape fragmentation of non-wetland alpine meadows was reduced. The patches of sandy grasslands tended to be regular, and their spatial connectivity was reduced. The wetland regions of high ecological risk are concentrated in the central and southern parts of the Changshagongma Wetland Nature Reserve. Low-risk regions are mainly concentrated in the contiguous swamp meadows in the northwest and wetlands in the southwest. From 1992 to 2020, the level of ecological risk of the Changshagongma Wetland Nature Reserve showed a "perpendicular to"-shaped trend, with the highest risk in 2002 and the lowest risk in 2020. Among the selected indicators, climate conditions constituted the main factor affecting the ecological risk of the Changshagongma Wetland Nature Reserve, followed by topographical conditions, and human activities were the least influential. Over the past 30 years, the temperature and precipitation in the study area increased significantly. The climate in the study area can be roughly divided into two periods bounding 2002, and the climate has been changing from cold and dry to warm and wet. The ecological environment of the study area is affected by natural and human activities. Cold and dry climatic conditions and uncontrolled grazing accelerate the destruction of the wetland ecological environment, and warm and wet climatic conditions and ecological conservation policies are conducive to the ecological restoration of wetlands. In general, the wetland landscape structure in the study area has become less complex, landscape heterogeneity has decreased, and ecological quality has improved. C1 [Yang, Cai; Deng, Wei; Yuan, Quanzhi; Zhang, Shaoyao] Sichuan Normal Univ, Sch Geog & Resource Sci, Chengdu, Peoples R China. [Deng, Wei; Yuan, Quanzhi; Zhang, Shaoyao] Res Ctr Resource Environm & Sustainable Dev West, Chengdu, Peoples R China. RP Deng, W (通讯作者)，Sichuan Normal Univ, Sch Geog & Resource Sci, Chengdu, Peoples R China.; Deng, W (通讯作者)，Res Ctr Resource Environm & Sustainable Dev West, Chengdu, Peoples R China. EM dengwei@sicnu.edu.cn TC 1 Z9 1 PD APR 6 PY 2022 VL 10 AR 843714 DI 10.3389/fevo.2022.843714 UT WOS:000808930100001 DA 2023-03-23 ER PT J AU Cui, HW Wagg, C Wang, XT Liu, ZY Liu, K Chen, SY Chen, JW Song, HX Meng, LH Wang, JJ Yang, XL Kou, X Wang, YJ Wang, Y Jin, MH Xiao, S AF Cui, Hanwen Wagg, Cameron Wang, Xiangtai Liu, Ziyang Liu, Kun Chen, Shuyan Chen, Jingwei Song, Hongxian Meng, Lihua Wang, Jiajia Yang, Xiaoli Kou, Xi Wang, Yajun Wang, Yang Jin, Menghuan Xiao, Sa TI The loss of above- and belowground biodiversity in degraded grasslands drives the decline of ecosystem multifunctionality SO APPLIED SOIL ECOLOGY DT Article AB It is well established that grassland degradation negatively affects ecosystem functioning. Many studies have explored the changes of individual functions involved with grassland degradation, while fewer considered an ecosystem multifunctionality (EMF) summarizing the multiple simultaneous changes in the response of ecosystem functions to grassland degradation. Further, how changes in multiple ecosystem functions with grassland degradation in relation to above-and belowground biodiversity has been rarely explored. Here we assessed the effects of grassland degradation on nutrient cycling, biological productivity and overall EMF in a Tibetan Plateau alpine grassland. We quantified both the direct effect of grassland degradation and indirect effects mediated by changes in plant richness, soil biodiversity and abiotic factors, on EMF. We found that 1) there were negative effects of grassland degradation on EMF, plant richness and soil biodiversity; 2) EMF was positively related to plant richness, soil biodiversity and soil moisture, but not with soil pH; 3) grassland degradation had a strong negative direct effect on EMF and the positive interaction between aboveground and belowground biodiversity enhanced the negative effects on EMF, especially, through plant richness. Our study reveals how grassland degradation affects EMF directly and indirectly through biotic and abiotic pathways and highlights the importance of both above-and belowground biodiversity for maintaining multiple ecosystem functions. Protecting belowground diversity is as important as preserving aboveground diversity for maintaining ecosystem functioning and the restoration of degraded grassland ecosystem. C1 [Cui, Hanwen; Wang, Xiangtai; Liu, Ziyang; Liu, Kun; Chen, Shuyan; Chen, Jingwei; Song, Hongxian; Meng, Lihua; Wang, Jiajia; Yang, Xiaoli; Kou, Xi; Wang, Yajun; Wang, Yang; Jin, Menghuan; Xiao, Sa] Lanzhou Univ, Sch Life Sci, Tianshui Rd 222, Lanzhou, Gansu, Peoples R China. [Wagg, Cameron] Agr & Agri Food Canada, Fredericton Res & Dev Ctr, Lincoln Rd 850, Fredericton, NB, Canada. [Wagg, Cameron] Univ Zurich, Dept Evolutionary Biol & Environm Studies, Winterthurerstr 190, CH-8057 Zurich, Switzerland. RP Xiao, S (通讯作者)，Lanzhou Univ, Sch Life Sci, Tianshui Rd 222, Lanzhou, Gansu, Peoples R China. EM xiaos@lzu.edu.cn TC 4 Z9 4 PD APR PY 2022 VL 172 AR 104370 DI 10.1016/j.apsoil.2021.104370 UT WOS:000777765300008 DA 2023-03-23 ER PT J AU Li, CH Sun, H Liu, LH Dou, TB Zhou, M Li, WP Wu, XD AF Li, Chuanhua Sun, Hao Liu, Lihui Dou, Tianbao Zhou, Min Li, Wangping Wu, Xiaodong TI The importance of permafrost in the steady and fast increase in net primary production of the grassland on the Qinghai-Tibet Plateau SO CATENA DT Article AB Permafrost affects soil water and soil temperature regimes; however, its effects on net primary production (NPP) remain unknown. Here, we examined temporal-spatial changes in grassland NPP during 2000-2018 in perma-frost and permafrost-free areas on the Qinghai-Tibetan Plateau using the random forest (RF) and radial basis function artificial neural network (RBF-ANN). Our results indicated that the areas that showed increasing, decreasing, and non-significant trends for NPP accounted for 13.88%, 1.90%, and 84.22% of the permafrost area, respectively. For the permafrost-free areas, these NPP trends accounted for 22.25%, 2.68%, and 75.07% of the permafrost-free area, respectively. The mean NPP in the permafrost regions showed a faster and steadier (1.520 g C/m(2)/yr, p < 0.05) increase than in non-permafrost regions (1.224 g C/m(2)/yr, p < 0.05). The Biome-BGC model confirmed that these spatial NPP patterns could be attributed to differences in soil water and soil temperature between permafrost and permafrost-free areas. Both the soil temperature and soil water content in permafrost sites exhibited relatively lower variance than in permafrost-free sites. Although many factors may be attributed to these patterns, our results suggest that there is a possibility that the relatively stable change in permafrost NPP can be explained by the fact that permafrost can regulate soil water and temperature regimes. Therefore, climate warming can increase NPP in cold regions, and permafrost degradation may destabilize the grassland ecosystem, which may cause NPP values to exhibit greater interannual changes in the future. C1 [Li, Chuanhua; Sun, Hao; Liu, Lihui; Dou, Tianbao; Zhou, Min] Northwest Normal Univ, Coll Geog & Environm Sci, Key Lab Resource Environm & Sustainable Dev Oasis, Lanzhou 730070, Peoples R China. [Li, Chuanhua; Wu, Xiaodong] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou 730070, Peoples R China. [Sun, Hao] Qinghai Inst Geol Environm Monitoring, Xining 810000, Peoples R China. [Li, Wangping] Lanzhou Univ Technol, Sch Civil Engn, Lanzhou 730050, Peoples R China. [Wu, Xiaodong] Univ Chinese Acad Sci, Beijing 100039, Peoples R China. RP Wu, XD (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou 730070, Peoples R China. EM wuxd@lzb.ac.cn TC 2 Z9 2 PD APR PY 2022 VL 211 AR 105964 DI 10.1016/j.catena.2021.105964 UT WOS:000790468400003 DA 2023-03-23 ER PT J AU Liu, YX Liu, SL Sun, YX Sun, J Wang, FF Li, MQ AF Liu, Yixuan Liu, Shiliang Sun, Yongxiu Sun, Jian Wang, Fangfang Li, Mingqi TI Effect of grazing exclusion on ecosystem services dynamics, trade-offs and synergies in Northern Tibet SO ECOLOGICAL ENGINEERING DT Article AB The relationships between different ecosystem services are key to regional ecological stability and security, and their trade-offs and synergies are affected by many factors, especially on the Qinghai-Tibet Plateau (QTP), which is susceptible to human activities. Norther Tibet, located on the QTP, has built fences for grazing exclusion in recent years. However, how grazing exclusion affect the ecosystem service variability and their mechanism remains still unclear. Based on the net primary productivity (NPP) quantitative index method, hotspot analysis, geographically weighted regression (GWR) model, this study analyzed the effects of grazing exclusion with fencing on ecosystem services dynamics, trade-offs and synergies. Results showed that the values of biodiversity conservation, water conservation and soil conservation were all higher in the fencing region than in the nonfencing region. Most counties experienced increasing trends in the fencing region with higher biodiversity conservation, water conservation in the fencing region than that in the non-fencing region from 2006 to 2015. Except for the relationship between soil conservation and water conservation in the non-fencing region in Cuoqin county in 2015, the relationships among all ecosystem services were synergistic, and the overall trends were weakening. The county number percentage with higher synergistic relationships in the fencing region than that in the non-fencing region showed gradually increasing trends. Land use intensity, grazing intensity, precipitation and altitude were the main factors that affecting spatial heterogeneity of three ecosystem services in the nonfencing region, while distance to road, distance to town, land use intensity and temperature were the main influencing factors in the fencing region. This study contributes to exploring the effect of grazing exclusion on ecosystem services and their relationships, thus providing guidance for the formulation of grassland restoration measures C1 [Liu, Yixuan; Liu, Shiliang; Sun, Yongxiu; Wang, Fangfang; Li, Mingqi] Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. [Sun, Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. RP Liu, SL (通讯作者)，Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM shiliangliu@bnu.edu.cn TC 4 Z9 5 PD JUN PY 2022 VL 179 AR 106638 DI 10.1016/j.ecoleng.2022.106638 EA MAR 2022 UT WOS:000792902500001 DA 2023-03-23 ER PT J AU Zhou, HC Ma, AZ Zhou, XR Chen, XK Zhang, JJ Zhang, QW Qi, XN Liu, GH Zhuang, GQ AF Zhou, Hanchang Ma, Anzhou Zhou, Xiaorong Chen, Xianke Zhang, Jiejie Zhang, Qinwei Qi, Xiangning Liu, Guohua Zhuang, Guoqiang TI Phosphorus Shapes Soil Microbial Community Composition and Network Properties During Grassland Expansion Into Shrubs in Tibetan Dry Valleys SO FRONTIERS IN PLANT SCIENCE DT Article AB Alpine ecosystem stability and biodiversity of the Tibetan plateau are facing threat from dry valley vegetation uplift expansion, a process which is highly connected to variations in the soil microbial community and soil nutrients. However, the variation of microbial community properties and their relationship to soil nutrients have scarcely been explored in Tibetan dry valleys, which is a gap that hampers understanding the dry valley ecosystem's response to vegetation change. In this study, we sampled grasslands (G), a grass-shrub transition area (T), and shrublands (S) along an uplift expansion gradient and investigated the link between microbial community properties and soil nutrients. The results showed that shrub degradation by grass expansion in Tibetan dry valley was accompanied by increasing relative phosphorus (P) limitation, which was the main driver for bacterial and fungal composition variation as it offered highest total effect on PC1 (0.38 and 0.63, respectively). Total phosphorus (TP) was in the center module of bacterial and fungal network under shrub soil and even acted as key nodes in fungal networks. During the replacement by grass, TP was gradually marginalized from both bacterial and fungal center network module and finally disappeared in networks, with ammonia and nitrate gradually appearing in the bacterial network. However, TC and total nitrogen (TN) were always present in the center modules of both fungal and bacterial network. These support that a TP variation-induced compositional and network functional shift in the microbial community was a potential reason for vegetation uplift expansion in Tibetan dry valley. This study highlighted the effect of TP on microbial community properties during dry valley vegetation uplift expansion and offered basic information on Tibetan alpine dry valley ecosystem's response to climate change. C1 [Zhou, Hanchang; Ma, Anzhou; Zhou, Xiaorong; Chen, Xianke; Zhang, Jiejie; Zhang, Qinwei; Qi, Xiangning; Liu, Guohua; Zhuang, Guoqiang] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, Beijing, Peoples R China. [Zhou, Hanchang; Ma, Anzhou; Zhou, Xiaorong; Chen, Xianke; Zhang, Jiejie; Zhang, Qinwei; Qi, Xiangning; Liu, Guohua; Zhuang, Guoqiang] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. RP Ma, AZ; Zhuang, GQ (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, Beijing, Peoples R China.; Ma, AZ; Zhuang, GQ (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. EM azma@rcees.ac.cn; gqzhuang@rcees.ac.cn TC 1 Z9 1 PD MAR 23 PY 2022 VL 13 AR 848691 DI 10.3389/fpls.2022.848691 UT WOS:000780192300001 DA 2023-03-23 ER PT J AU Wu, SN Wen, L Dong, SK Gao, XX Xu, YD Li, S Dong, QM Wessell, K AF Wu, Shengnan Wen, Lu Dong, Shikui Gao, Xiaoxia Xu, Yudan Li, Shuai Dong, Quanming Wessell, Kelly TI The Plant Interspecific Association in the Revegetated Alpine Grasslands Determines the Productivity Stability of Plant Community Across Restoration Time on Qinghai-Tibetan Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB Grassland cultivation is the key measure for restoring "Black Beach," the extremely degraded alpine meadow in the Three River Headwater Area of the Qinghai-Tibetan Plateau. In this study, we examined the inter-specific relationship in the vegetation community of cultivated grasslands with different restoration times through the network analysis method. The results showed that with the extension of restoration time, the development of cultivated grassland would lead to increasing neutral interactions among the plant species. The proportion of species with positive and negative associations in the community decreased, while the number of species-independent pairs increased significantly. The complexity of plant interspecific association (species network density) had more influence on community stability with the extension of recovery time, which can be used to quantify the characteristics of community structure. C1 [Wu, Shengnan; Dong, Shikui] Beijing Forestry Univ, Sch Grassland Sci, Beijing, Peoples R China. [Wen, Lu] Inner Mongolia Univ, Sch Ecol & Environm, Minist Educ, Key Lab Ecol & Resource Use Mongolian Plateau, Hohhot, Peoples R China. [Wen, Lu] Inner Mongolia Univ, Sch Ecol & Environm, Inner Mongolia Key Lab Grassland Ecol, Hohhot, Peoples R China. [Gao, Xiaoxia] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. [Xu, Yudan] Shanxi Agr Univ, Coll Grassland Sci, Jinzhong, Peoples R China. [Li, Shuai] Shanxi Agr Univ, Coll Resources & Environm, Jinzhong, Peoples R China. [Dong, Quanming] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Xining, Peoples R China. [Wessell, Kelly] Tompkins Cortland Community Coll, Dryden, NY USA. RP Dong, SK (通讯作者)，Beijing Forestry Univ, Sch Grassland Sci, Beijing, Peoples R China.; Wen, L (通讯作者)，Inner Mongolia Univ, Sch Ecol & Environm, Minist Educ, Key Lab Ecol & Resource Use Mongolian Plateau, Hohhot, Peoples R China.; Wen, L (通讯作者)，Inner Mongolia Univ, Sch Ecol & Environm, Inner Mongolia Key Lab Grassland Ecol, Hohhot, Peoples R China. EM wenlu5210@126.com; dongshikui@bjfu.edu.cn TC 4 Z9 4 PD MAR 21 PY 2022 VL 13 AR 850854 DI 10.3389/fpls.2022.850854 UT WOS:000782136100001 DA 2023-03-23 ER PT J AU Jin, XY Jin, HJ Luo, DL Sheng, Y Wu, QB Wu, JC Wang, WH Huang, S Li, XY Liang, SH Wang, QF He, RX Serban, RD Ma, Q Gao, SH Li, Y AF Jin, Xiaoying Jin, Huijun Luo, Dongliang Sheng, Yu Wu, Qingbai Wu, Jichun Wang, Wenhui Huang, Shuai Li, Xiaoying Liang, Sihai Wang, Qingfeng He, Ruixia Serban, Raul D. Ma, Qiang Gao, Shuhui Li, Yan TI Impacts of Permafrost Degradation on Hydrology and Vegetation in the Source Area of the Yellow River on Northeastern Qinghai-Tibet Plateau, Southwest China SO FRONTIERS IN EARTH SCIENCE DT Article AB Under a persistent warming climate and increasing human activities, permafrost in the Source Area of the Yellow River (SAYR) has been degrading regionally, resulting in many eco-environmental problems. This paper reviews the changes in air temperature and precipitation over the past 60 years and presents the distribution and degradation of alpine permafrost in the SAYR. The review is focused on the permafrost degradation-induced changes in hydrology, wetlands, thermokarst lakes, ponds, and vegetation. Mean annual air temperatures have been rising at an average rate of 0.4 degrees C/10a over the past 60 years, while precipitation has increased only slightly (16 mm/10a). Borehole temperature monitoring at the depth of 15 m shows the permafrost warming rates of 0.01-0.21 degrees C/10a in the Headwater Aera of the Yellow River. As a result of permafrost thaw, the amount of surface waters has declined while groundwater storage has increased. Due to permafrost degradation, the supra-permafrost water table lowers gradually, resulting in a reduction in areal extents of wetlands and lakes in the SAYR. We further renamed the concept of the burial depth of the ecologically-safe supra-permafrost water table, the minimum depth of the groundwater table for sustaining the normal growth of alpine grassland vegetation, for the SAYR to describe the relationship between the lowering permafrost table and succeeding alpine vegetation. Furthermore, we recommended more studies focusing on snow cover and carbon stock and emissions related to permafrost degradation under a warming climate. We also advised to timely establish the long-term monitoring networks for the rapidly changing mountain cryosphere, alpine ecology, alpine hydrology, eco-hydrology, cryo-hydrogeology, and carbon fluxes. Moreover, process-based models should be developed and improved to better simulate and predict the responses of alpine ecosystem changes to the interacting cryospheric and other environmental variables and their ecological and ecohydrological impacts in the SAYR and downstream Yellow River basins. This study can help better manage the ecological and hydrological environments in the Upper Yellow River that are sensitive to changes in the alpine climate and cryosphere. C1 [Jin, Xiaoying; Jin, Huijun; Wang, Wenhui; Huang, Shuai] Northeast Forestry Univ, Sch Civil Engn, Harbin, Peoples R China. [Jin, Xiaoying; Jin, Huijun] Northeast Forestry Univ, Inst Cold Reg Sci & Engn, Harbin, Peoples R China. [Jin, Huijun; Luo, Dongliang; Sheng, Yu; Wu, Qingbai; Wu, Jichun; Wang, Qingfeng; He, Ruixia; Serban, Raul D.; Ma, Qiang; Gao, Shuhui; Li, Yan] Chinese Acad Sci, Northwest Inst Ecoenvironm & Engn, State Key Lab Frozen Soils Engn, Lanzhou, Peoples R China. [Li, Xiaoying] Northeast Forestry Univ, Sch Forestry, Harbin, Peoples R China. [Liang, Sihai] China Univ Geosci, Sch Water Resources & Environm, Beijing, Peoples R China. [Serban, Raul D.] Eurac Res, Inst Alpine Environm, Bolzano, Italy. [Gao, Shuhui] Lanzhou Jiaotong Univ, Sch Civil Engn, Lanzhou, Peoples R China. RP Jin, HJ (通讯作者)，Northeast Forestry Univ, Sch Civil Engn, Harbin, Peoples R China.; Jin, HJ (通讯作者)，Northeast Forestry Univ, Inst Cold Reg Sci & Engn, Harbin, Peoples R China.; Jin, HJ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Engn, State Key Lab Frozen Soils Engn, Lanzhou, Peoples R China. EM hjjin@lzb.ac.cn TC 9 Z9 9 PD MAR 15 PY 2022 VL 10 AR 845824 DI 10.3389/feart.2022.845824 UT WOS:000777752800001 DA 2023-03-23 ER PT J AU Liu, MK Huang, LH Li, XS Liu, F Zhang, W Wang, Z Xu, Y Ke, RH He, HP Lou, YH AF Liu, Mingkai Huang, Longhua Li, Xiaoshuang Liu, Fei Zhang, Wei Wang, Zhe Xu, Yan Ke, Runhui He, Hongping Lou, Yinghua TI Occurrence and distribution of polyhalogenated carbazoles in eastern Tibetan Plateau soils along the slope of Mt. Qionglai SO CHEMOSPHERE DT Article AB Polyhalogenated carbazoles (PHCZs), are considered as potential persistent organic pollutants (POPs), which have been frequently detected in the environment. However, the altitudinal distribution characteristics and possible sources of PHCZs in high mountain soils are still unknown. The present study was the first to analyze PHCZs in soil samples collected along the eastern slope of Mt. Qionglai (MQ), the east edge of the Tibetan Plateau. The concentration of sigma PHCZs (based on dry weight) ranges from 14.4 to 107 ng/g (median value of 40.9), which was at high end of the range reported in soils and sediments to date in the literature. The composition profiles of PHCZs in the soils of MQ were dominated by 3,6-dichlorocarbazole (36-CCZ), 3-chlorocarbazole (3-CCZ), and 2-bromocarbazole (2-BCZ). The mean TOC-normalized concentrations of sigma PHCZs in soil samples from below-treeline (2092 ng/g TOC) were higher than those from alpine meadow (1124 ng/g TOC), probably due to the forest filter effect. The decreasing trend of the PHCZs TOC-normalized concentrations with altitude shows that accumulation of PHCZs from the alpine meadow samples was not affected by the mountain cold-trapping effect. Significantly positive correlations were observed between the concentrations of more than half of detected PHCZ congeners and TOC. In addition, PHCZs show the potential to represent a class of POPs with the frequent occurrence and wide distribution, as the abundance and environmental behavior of PHCZs are similar to some POPs in MQ. C1 [Liu, Mingkai; Li, Xiaoshuang; Liu, Fei; Zhang, Wei; Wang, Zhe; Xu, Yan; Lou, Yinghua] Qingdao Univ, Coll Environm Sci & Engn, Qingdao 266071, Peoples R China. [Huang, Longhua] Qingdao Univ, Coll Text Clothing, Qingdao 266071, Peoples R China. [Ke, Runhui] China Natl Res Inst Food Fermentat Ind, Beijing 10001, Peoples R China. [He, Hongping] Shenzhen Univ, Coll Chem & Environm Engn, Shenzhen 518060, Peoples R China. RP Lou, YH (通讯作者)，Qingdao Univ, Coll Environm Sci & Engn, Qingdao 266071, Peoples R China.; He, HP (通讯作者)，Shenzhen Univ, Coll Chem & Environm Engn, Shenzhen 518060, Peoples R China. EM hehp@szu.edu.cn; yinghualou@qdu.edu.cn TC 2 Z9 2 PD JUL PY 2022 VL 298 AR 134200 DI 10.1016/j.chemosphere.2022.134200 EA MAR 2022 UT WOS:000778171900004 DA 2023-03-23 ER PT J AU Brierley, G Li, XL Fryirs, K Gao, J Shi, Y Perry, GLW Cullum, C AF Brierley, Gary Li, Xilai Fryirs, Kirstie Gao, Jay Shi, Yan Perry, George L. W. Cullum, Carola TI Development of place-based catenal models for grassland ecosystems of the Upper Yellow River, Western China SO CATENA DT Article AB Careful development of place-based catenal models and their application as transferable archetypes provides an integrative and generalisable framework for scientifically-informed approaches to environmental management. A workshop and field excursion to the Source Zone of the Yellow River in western China in July 2019 brought together local experts and a team of international researchers to co-develop cross-disciplinary, process-based catenal models that summarise controls on the character and behaviour of grassland environments in alpine meadow (3800 m asl) and alpine steppe (4200 m asl) landscapes. Water, sediment and nutrient fluxes, soil material properties, ground cover (especially percentage bare ground) and the role of small mammals (especially pika) are critical drivers of process linkages in the catenal models. Geologic, climatic and anthropogenic controls on these drivers vary in alpine steppe and alpine meadow settings. While these process interactions have supported grazing adapted ecosystems and sustained biodiversity values in this area for millennia, anthropogenic and climate change disturbances threaten the integrity of these landscapes and their capacity to provide ecosystem services and sustain livelihoods into the future. The place-based catenal models presented in this paper can be used to support applications that appropriately target key attributes, linkages and fluxes that may require conservation, maintenance or treatment in the management of alpine steppe and alpine meadow landscapes. C1 [Brierley, Gary; Gao, Jay; Shi, Yan; Perry, George L. W.; Cullum, Carola] Univ Auckland, Sch Environm, Private Bag 92019, Auckland 1081, New Zealand. [Li, Xilai] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Fryirs, Kirstie] Macquarie Univ, Sch Nat Sci, N Ryde, NSW 2019, Australia. RP Brierley, G (通讯作者)，Univ Auckland, Sch Environm, Private Bag 92019, Auckland 1081, New Zealand. EM g.brierley@auckland.ac.nz TC 3 Z9 3 PD JUN PY 2022 VL 213 AR 106193 DI 10.1016/j.catena.2022.106193 EA MAR 2022 UT WOS:000790435800002 DA 2023-03-23 ER PT J AU Yan, H Ran, QW Hu, RH Xue, K Zhang, BA Zhou, ST Zhang, ZP Tang, L Che, RX Pang, Z Wang, F Wang, D Zhang, J Jiang, LL Qian, Z Zhang, SG Guo, TD Du, JQ Hao, YB Cui, XY Wang, YF AF Yan, Han Ran, Qinwei Hu, Ronghai Xue, Kai Zhang, Biao Zhou, Shutong Zhang, Zuopei Tang, Li Che, Rongxiao Pang, Zhe Wang, Fang Wang, Di Zhang, Jing Jiang, Lili Qian, Zhi Zhang, Sanguo Guo, Tiande Du, Jianqing Hao, Yanbin Cui, Xiaoyong Wang, Yanfen TI Machine learning-based prediction for grassland degradation using geographic, meteorological, plant and microbial data SO ECOLOGICAL INDICATORS DT Article AB Extensive grassland degradation under climate change and intensified human activities has threatened ecological security and caused a variety of environmental problems. However, it is still challenging to predict the grassland degradation status on a large scale because it is a multi-factorial phenomenon with complex changes in ecosystem structure and function, which is hard to be fully characterized through mechanism models. The emergence of machine learning algorithms provides a potential to model complex systems and mine information from multi-source data without elucidating underlying mechanisms. Here, we utilized random forest and neural network algorithms to predict the grassland degradation represented by the net primary productivity (NPP) changing rate based on multi-source data including geographic, meteorological, plant traits, land use type and microbial variables in the Chinese Northern grassland. Particularly, the microbial roles in determining the degradation status were concerned. Results show that a high prediction precision was achieved by random forest model, rather than by neural network model, with a mean relative error of 16.9% and a mean square error of 9.273e-05. Besides identified longitude, arid index and current NPP state, specific soil microbial groups, mainly Solirubrobacter, were screened as credible biomarkers. Regarding model fitting, geographic, meteorological and plant variables explained 61.8% of the total variance, which was enhanced up to 72.8% by the rest microbial markers. These findings provide a theoretical basis to establish a pre-warning system for grassland management and policy-making. C1 [Yan, Han; Hu, Ronghai; Xue, Kai; Zhang, Biao; Zhang, Zuopei; Tang, Li; Pang, Zhe; Qian, Zhi; Du, Jianqing; Wang, Yanfen] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Ran, Qinwei; Zhou, Shutong; Wang, Fang; Hao, Yanbin; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Hu, Ronghai; Xue, Kai; Du, Jianqing; Hao, Yanbin; Cui, Xiaoyong; Wang, Yanfen] Univ Chinese Acad Sci, Yanshan Earth Crit Zone & Surface Fluxes Res Stn, Beijing 100049, Peoples R China. [Xue, Kai] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. [Che, Rongxiao] Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming 650091, Yunnan, Peoples R China. [Wang, Di] Chinese Acad Sci, Inst Biophys, Beijing 100101, Peoples R China. [Zhang, Jing] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100049, Peoples R China. [Jiang, Lili] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Zhang, Sanguo; Guo, Tiande] Univ Chinese Acad Sci, Sch Math Sci, Beijing 100049, Peoples R China. [Wang, Yanfen] State Key Lab Tibetan Plateau Earth Syst Sci LATP, Beijing 100101, Peoples R China. RP Wang, YF (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM yfwang@ucas.ac.cn TC 3 Z9 3 PD APR PY 2022 VL 137 AR 108738 DI 10.1016/j.ecolind.2022.108738 EA MAR 2022 UT WOS:000780227000005 DA 2023-03-23 ER PT J AU Qi, J Liu, WH Hamblin, A Che, MM AF Qi, Juan Liu, Wen-Hui Hamblin, Ann Che, Meimei TI Zinc and Cadmium Tolerance in Different Ecotypes of Elymus Nutans from Alpine Grassland of Qinghai-Tibet Plateau SO COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS DT Article AB Qinghai-Tibet Plateau was a clean environment in the past. Zinc (Zn) and cadmium (Cd) present in soils now. We postulated that the dominant native grass Elymus nutans is tolerant to Zn and Cd. We investigated the effects of Cd-Zn interactions on seed germination, seedling growth, physiological stress, and their uptake in plants of E. nutans. Two ecotypes, Population1 (POP1, altitude 2450 m) and Population2 (POP2, 3300 m), were selected from alpine grassland of Qinghai-Tibet Plateau. Germination and growth parameters were measured after Cd as CdSO4 center dot 8H(2)O (15-100 mg l(-1)) and Zn as ZnSO4 center dot 7H(2)O (40-300 mg l(-1)) were applied. Zn and Cd affected the germination and early seedling growth of both ecotypes. Below 50 mg l(-1), Zn promoted seed germination and plant growth, while 300 mg l(-1) Zn significantly inhibited it. All levels of Cd had an inhibitory effect. Zn and Cd affected the POP2 above-ground dry weight more than POP1 and reduced root growth more than shoot growth. The measurement of metal accumulation showed that Zn application suppressed Cd accumulation in plants under the lower Cd (< 20 mg l(-1)) treatments, while above 20 mg l(-1), Cd had an antagonistic effect on Zn uptake. Cadmium and Zn alone or in combination induced oxidative stress. The results suggest that responses to Cd and Zn and their interactions vary with concentration: moderate levels of heavy metals activated the species' protective system, but higher concentrations destroyed it. We concluded that this species has differing abilities to tolerate Zn and Cd related to their original habitats. C1 [Qi, Juan; Che, Meimei] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou, Gansu, Peoples R China. [Liu, Wen-Hui] Qinghai Univ, Qinghai Acad Anim Sci & Vet Med, Xining, Qinghai, Peoples R China. [Hamblin, Ann] Univ Western Australia, Dept Agr & Environm Sci, Perth, WA, Australia. RP Qi, J (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, 1 Yingmen Village, Lanzhou 730070, Gansu, Peoples R China. EM qijuan0622@163.com TC 0 Z9 0 PD MAY 15 PY 2022 VL 53 IS 9 BP 1158 EP 1175 DI 10.1080/00103624.2022.2043346 EA MAR 2022 UT WOS:000764947700001 DA 2023-03-23 ER PT J AU Cui, Z Yang, WS Cheng, Z Zhang, ZC Li, SX Zhao, JX Lopez-Vicente, M Wu, GL AF Cui, Zeng Yang, Wen-Shan Cheng, Zhen Zhang, Zhenchao Li, Shixiong Zhao, Jingxue Lopez-Vicente, Manuel Wu, Gao-Lin TI Top-down degradation of alpine meadow in the Qinghai-Tibetan Plateau: Gravelization initiate hillside surface aridity and meadow community disappearance SO CATENA DT Article AB Alpine gravelization by glacier melting may subsequently cause degradation of downstream vegetation. The thinning rates of glaciers outside ice sheet peripheries in some regions has doubled over the past 20 years. However, no study is available about the effects of alpine gravelization on alpine meadow ecosystem. Here, by investigating and measuring the community characteristics, soil moisture, and soil temperature of alpine meadows under three different gravel coverage levels (No gravel covered meadow, half gravel covered meadow, and fully gravel covered meadow), we examine the response of surface microhabitats and community to gravel cover on a typical hillside alpine meadow. Results showed that gravel cover significantly decreased soil/gravel ratio and topsoil moisture. Topsoil water content of the half-covered and the fully-covered gravel meadow was outstandingly low and reached<8% and 5%, respectively. Meanwhile, the larger decrease rates for coverage (-72.53%), above-and below-ground biomass (-76.61% and-94.09%), community density (-81.76%), species richness (-77.75%) and diversity (-55.98%) were found after gravel cover. Gravel cover induced the changes of the dominant species composition from Kobresia pygmaea to Setaria viridis, and ultimately to Trigonotis peduncularis and Ranunculus pedatifidus. Cyperaceae functional group species almost disappeared with increasing gravel coverage. In general, the increase in gravel coverage caused a decrease in soil water content, coverage, above-ground and under-ground biomass, community density, species richness, and the disappearance of Cyperaceae functional group species. Our results provide a new insight into the effect of alpine gravelization on soil water environment and alpine meadow degradation. C1 [Cui, Zeng; Yang, Wen-Shan; Cheng, Zhen; Zhang, Zhenchao; Wu, Gao-Lin] Chinese Acad Sci & Minist Water Resource, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Cui, Zeng; Yang, Wen-Shan; Cheng, Zhen; Zhang, Zhenchao; Wu, Gao-Lin] Northwest A&F Univ, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. [Cui, Zeng; Wu, Gao-Lin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Li, Shixiong; Wu, Gao-Lin] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Qinghai Prov Key Lab Adapt Management Alpine Gras, Xining 810016, Peoples R China. [Zhao, Jingxue] Lanzhou Univ, Inst Innovat Ecol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Zhao, Jingxue] Lanzhou Univ, Coll Life Sci, Lanzhou 730000, Peoples R China. [Lopez-Vicente, Manuel] Univ A Coruna, Adv Sci Res Ctr, Grp Aquaterra, As Carballeiras S-N,Campus Elvina, La Coruna 15071, Spain. [Wu, Gao-Lin] CAS Ctr Excellence Quaternary Sci & Global Change, Xian 710061, Peoples R China. RP Wu, GL (通讯作者)，Chinese Acad Sci & Minist Water Resource, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. EM wugaolin@nwsuaf.edu.cn TC 2 Z9 2 PD MAR PY 2022 VL 210 AR 105933 DI 10.1016/j.catena.2021.105933 UT WOS:000788531100005 DA 2023-03-23 ER PT J AU Du, CJ Zhou, GY Gao, YH AF Du, Chenjun Zhou, Guoying Gao, Yongheng TI Grazing exclusion alters carbon flux of alpine meadow in the Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Grasslands contain a large global pool of soil organic carbon (C), but the carbon flux in response to grazing exclusion and the affecting factors are still under debate. In this study, a manipulative experiment was conducted in alpine meadow of the eastern Tibetan Plateau. The sites were: 9 years grazing exclusion, GE9; 5 years grazing exclusion, GE5; and free grazing, FG in degraded alpine meadow. Results showed that there had been a significant increase in soil respiration (SR) and net ecosystem exchange (NEE) with fencing duration. However, no significant difference of ecosystem respiration (ER) was found between grazing and fencing sites. Though, carbon sink occurred in all three sites during the growing season, only the site for 9 years fencing increased gross ecosystem productivity (GEP). Remarkably, temperature sensitivity (Q(10)) of both soil and ecosystem respiration raised in GE5 but declined in GE9. These findings indicated that grazing exclusion could be a promising measure to CO2 sequestration in alpine meadow. Of the governing factors, exponential relationships among SR, ER and soil temperature and significant relationships among NEE, GEP and plant biomass were found. Besides, our results showed that plant nitrogen (N), phosphorus (P) content exhibited significant effects on SR, NEE, respectively. While soil C and N were significant explanatory factors for ER. These results indicated that C, N, and P content of plant and soil could provide a new insight for understanding carbon flux in alpine meadow. Together, the findings are not only vital to improve understanding of C cycle in grasslands, but also to provide scientific data for assessing the ecological effect and carbon budget of grazing exclusion. C1 [Du, Chenjun] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Du, Chenjun] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhou, Guoying] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Chengdu Inst Biol, CAS Key Lab Mt Ecol Restorat & Bioresource Utiliz, Chengdu 610041, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat & Biodivers Conservat Key Lab Sichu, Chengdu 610041, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. RP Gao, YH (通讯作者)，Chengdu Inst Biol, South Renmin Rd, Chengdu 610041, Peoples R China. EM gaoyh@cib.cas.cn TC 0 Z9 0 PD MAR 1 PY 2022 VL 314 AR 108774 DI 10.1016/j.agrformet.2021.108774 UT WOS:000819806600002 DA 2023-03-23 ER PT J AU Li, J Zhang, FW Si, MK Lan, YT Li, BC Lin, L Du, YG Cao, GM Guo, XW AF Li, Jing Zhang, Fawei Si, Mengke Lan, Yuting Li, Bencuo Lin, Li Du, Yangong Cao, Guangmin Guo, Xiaowei TI Response of Soil Water Storage to Meteorological Factors in Alpine Shrub Meadow on Northeastern Qinghai-Tibetan Plateau SO DIVERSITY-BASEL DT Article AB The Qinghai-Tibet Plateau (QTP) has an important function in ensuring the water ecological security of China, even Asia, and the soil water storage of alpine grassland is an important part of the ecosystem water. Grassland degradation directly affects the soil water storage capacity. However, the impact of degradation on specific soil storage capacity, especially alpine shrubs, is rarely studied. Here, we chose two plots of alpine non-degraded shrub and degraded shrub, using the automatic soil moisture monitoring system to study the change process of soil moisture storage, and then adopted the boosted regression tree (BRT) model to quantitatively evaluate the relative influence of environmental variables on soil water storage. Our results show: (1) The soil water storage in the growing season (May-September) is higher than that in the non-growing season (January-April and October-December), and the soil water storage reaches its highest in mid-July. (2) During the growing season, the 100 cm soil temperature was the most important factor affecting the seasonal variation in soil water storage, accounting for 51% of the total variation. During the non-growing season, the 40 cm soil temperature was the most important factor affecting the variation in soil water storage, accounting for 80% of the total variation. (3) The soil water storage of non-degraded Potentilla fruticosa shrub meadow increased by 6-25%, compared with degraded grassland shrub meadow during growing-season. (4) Various meteorological factors have a weak impact on soil water storage. C1 [Li, Jing; Zhang, Fawei; Si, Mengke; Lan, Yuting; Li, Bencuo; Lin, Li; Du, Yangong; Cao, Guangmin; Guo, Xiaowei] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. [Li, Jing] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100043, Peoples R China. [Zhang, Fawei; Si, Mengke; Lan, Yuting; Li, Bencuo; Lin, Li; Du, Yangong; Cao, Guangmin; Guo, Xiaowei] Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810001, Peoples R China. RP Cao, GM; Guo, XW (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China.; Cao, GM; Guo, XW (通讯作者)，Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810001, Peoples R China. EM lijing@nwipb.cas.cn; fwzhang@nwipb.cas.cn; simengke@nwipb.cas.cn; lanyt@nwipb.cas.cn; libencuo@nwipb.cas.cn; lil@nwipb.cas.cn; ygdu@nwipb.cas.cn; caogm@nwipb.cas.cn; guoxw@nwipb.cas.cn TC 1 Z9 1 PD MAR PY 2022 VL 14 IS 3 AR 185 DI 10.3390/d14030185 UT WOS:000775449000001 DA 2023-03-23 ER PT J AU Lin, L Cao, GM Xu, XL Li, CL Fan, B Li, BC Lan, YT Si, MK Dai, LC AF Lin, Li Cao, Guangmin Xu, Xingliang Li, Chunli Fan, Bo Li, Bencuo Lan, Yuting Si, Mengke Dai, Licong TI Changes and Relationships between Components in the Plant-Soil System and the Dominant Plant Functional Groups in Alpine Kobresia Meadows Due to Overgrazing SO DIVERSITY-BASEL DT Article AB In the last several decades, overgrazing has led to various changes in the plant communities, soil nutrients and soil microbial communities in alpine Kobresia meadows, which contain various plant communities coexisting on the Qinghai-Tibet Plateau. Investigating the variations in the biomass and concentration of nutrients in the plant-soil system in these communities may improve understanding of the biochemical responses and adaptation strategies they use to resist disturbances due to overgrazing. We therefore assessed 12 factors across four grazing intensities in alpine Kobresia meadows to explore the following three questions. (1) What the responses are in alpine Kobresia meadows to overgrazing. (2) How they affect plant-soil systems in alpine Kobresia meadows under overgrazing. (3) What factors can be used to evaluate the effects of overgrazing on the ecosystem health status of alpine Kobresia meadows. The results gave the following answers to the above questions. (1) Overgrazing caused the total aboveground biomass to decrease from 333.2 +/- 17.4 g/m(2) to 217.4 +/- 30.2 g/m(2), the coverage of plant functional groups of Gramineae and Cyperaceae to decrease from 74.2 +/- 3% to 22.5 +/- 1.9%, and the total belowground biomass to increase from 4028.5 +/- 7.3 g/m(2) to 6325.6 +/- 24.8 g/m(2). (2) Overgrazing resulted in variations in plant-soil systems at three levels. The concentrations of carbon (C) in soil nutrients and plant communities, explained 50.9% of the variation of biomass in plant functional groups; the concentration of soil available nutrients, explained 22.2% of the variation; and the ratio of C and N in shoots and soil total N, explained 11.0% of the variation. (3) The variations in C/N stoichiometry in total soil nutrients and soil microorganisms were 3.4-8.4% and 2.0-3.0%, respectively, and the load of (ammonium-nitrogen (NH4+-N) + nitrate-nitrogen (NO3--N)) to growth of roots tissue increased from 84.1 +/- 5.0 g/m(2)/(mg/kg) via 99.0 +/- 1.3 g/m(2)/(mg/kg) to 86.1 +/- 2.1 g/m(2)/(mg/kg) at 0 to 40 cm soil in an alpine meadow with grazing intensities rising. Overgrazing would thus increase the deficit of those two kinds of inorganic N on roots growing by 11.4%, 17.7% and 2.4% as grazing rates increased by 93.3%, 126.7% and 213.3%, respectively, compared to a meadow grazed at the lowest rate in the research. We concluded that the alpine meadow changed its distribution of biomass in the plant community, which increased the limiting nutrient deficit on production and altered the concentration and ratio of C and N. This destroyed the original balance to enable the plant community to resist overgrazing. Plot "KH"-a pasture with a grazing intensity next to the lowest one-was the key state in which persistent overgrazing could increase the limiting nutrient load on plant community production, change the dominant position of functional plant groups and species, and lead to plant community degradation. Using ratio of Gramineae to Cyperaceae or Kobresia humilis to K. pygmaea to monitor plant community succession could indirectly estimate these limiting nutrients deficit and balance, and their strategy for incorporating matter into roots and shoots. However how to use those outward characteristics to assess the ecosystem health requires further studies. C1 [Lin, Li; Cao, Guangmin; Fan, Bo; Li, Bencuo; Lan, Yuting; Si, Mengke] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Peoples R China. [Lin, Li] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 130028, Peoples R China. [Li, Chunli] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Dai, Licong] Hainan Univ, Coll Ecol & Environm, Haikou 570228, Hainan, Peoples R China. RP Cao, GM (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Peoples R China.; Xu, XL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 130028, Peoples R China. EM hanxiao2000_00@126.com; caogm@nwipb.cas.cn; xuxingl@hotmail.com; lclmiss@163.com; fanbo@nwipb.cas.cn; libencuo@nwipb.cas.cn; lanyt@nwipb.cas.cn; simengke@nwipb.cas.cn; licongdai1993@163.com TC 4 Z9 4 PD MAR PY 2022 VL 14 IS 3 AR 183 DI 10.3390/d14030183 UT WOS:000775514300001 DA 2023-03-23 ER PT J AU Lu, XM Liang, EY Babst, F Camarero, JJ Buntgen, U AF Lu, Xiaoming Liang, Eryuan Babst, Flurin Julio Camarero, J. Buentgen, Ulf TI Warming-induced tipping points of Arctic and alpine shrub recruitment SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA DT Article AB Shrub recruitment, a key component of vegetation dynamics beyond forests, is a highly sensitive indicator of climate and environmental change. Warming-induced tipping points in Arctic and alpine treeless ecosystems are, however, little understood. Here, we compare two long-term recruitment datasets of 2,770 shrubs from coastal East Greenland and from the Tibetan Plateau against atmospheric circulation patterns between 1871 and 2010 Common Era. Increasing rates of shrub recruitment since 1871 reached critical tipping points in the 1930s and 1960s on the Tibetan Plateau and in East Greenland, respectively. A recent decline in shrub recruitment in both datasets was likely related to warmer and drier climates, with a stronger May to July El Nino Southern Oscillation over the Tibetan Plateau and a stronger June to July Atlantic Multidecadal Oscillation over Greenland. Exceeding the thermal optimum of shrub recruitment, the recent warming trend may cause soil moisture deficit. Our findings suggest that changes in atmospheric circulation explain regional climate dynamics and associated response patterns in Arctic and alpine shrub communities, knowledge that should be considered to protect vulnerable high-elevation and high-latitude ecosystems from the cascading effects of anthropogenic warming. C1 [Lu, Xiaoming; Liang, Eryuan] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing 100101, Peoples R China. [Babst, Flurin] Univ Arizona, Sch Nat Resources & Environm, Tucson, AZ 85721 USA. [Babst, Flurin] Univ Arizona, Lab Tree Ring Res, Tucson, AZ 85721 USA. [Julio Camarero, J.] Consejo Super Invest Cient IPE CSIC, Inst Pirenaico Ecol, Zaragoza 50059, Spain. [Buentgen, Ulf] Univ Cambridge, Dept Geog, Cambridge CB2 3EN, England. [Buentgen, Ulf] Swiss Fed Res Inst, CH-8903 Birmensdorf, Switzerland. [Buentgen, Ulf] Czech Acad Sci CzechGlobe, Global Change Res Inst, Brno 60300, Czech Republic. [Buentgen, Ulf] Masaryk Univ, Fac Sci, Dept Geog, Brno 61300, Czech Republic. RP Liang, EY (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing 100101, Peoples R China. EM liangey@itpcas.ac.cn TC 7 Z9 7 PD MAR 1 PY 2022 VL 119 IS 9 AR e2118120119 DI 10.1073/pnas.2118120119 UT WOS:000766704900006 DA 2023-03-23 ER PT J AU Lv, MX Wang, YB Gao, ZY AF Lv, Mingxia Wang, Yibo Gao, Zeyong TI The change process of soil hydrological properties in the permafrost active layer of the Qinghai-Tibet Plateau SO CATENA DT Article AB The hydrological properties of the active soil layer are the key parameters that regulate soil water-heat-solute migration and alter hydrologic cycles in a permafrost region. To date, much remains unknown about the interaction mechanism between permafrost degradation and eco-hydrological processes in the permafrost regions of the Qinghai-Tibet Plateau (QTP). In this study, the soil texture, soil hydrological properties, the soil moisture status, and the hydrothermal processes were measured and analyzed in different degradation degrees of alpine meadow soils on the QTP. The results showed a close relationship between soil hydrological properties and soil physicochemical properties. Freeze-thaw cycles changed the physicochemical and hydrological properties, that is, frequent freeze-thaw cycles promote to permafrost degradation in terms of soil basis properties of active layer. In addition, vegetation on the ground delayed the degradation of frozen soil. The actual available soil water content (SWC) in the root layer was a key factor in the ecohydrological process. The actual effective SWC in the root layers of different alpine meadows was ranked as follows: non-degraded meadow (NDM) > moderately-degraded meadow (MDM) > seriously degraded meadow (SDM) (1.8-5.0% at NDM and 0.0-4.2% at SDM). In addition, the weak soilpermeability in an SDM intensified the deficiency of the available SWC, thereby increasingthe difficulty of ecological restoration. This study provides a basis for ecological environmental protection in permafrost regions and provides a hydrological process model for cold regions under future climate change scenarios. C1 [Lv, Mingxia; Wang, Yibo] Lanzhou Univ, Coll Earth & Environm Sci, 222 Tianshui South Rd, Lanzhou 730000, Gansu, Peoples R China. [Wang, Yibo; Gao, Zeyong] Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, CAS, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. RP Wang, YB (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, 222 Tianshui South Rd, Lanzhou 730000, Gansu, Peoples R China.; Wang, YB (通讯作者)，Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, CAS, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. EM wangyib@lzu.edu.cn TC 2 Z9 2 PD MAR PY 2022 VL 210 AR 105938 DI 10.1016/j.catena.2021.105938 UT WOS:000787584100003 DA 2023-03-23 ER PT J AU Shi, Y Gao, J Li, XL Li, JX Brierley, G AF Shi, Yan Gao, Jay Li, Xilai Li, Jiexia Brierley, Gary TI Effects of disturbances on aboveground biomass of alpine meadow in the Yellow River Source Zone, Western China SO ECOLOGY AND EVOLUTION DT Article AB A field experiment quantifies the impacts of two external disturbances (mowing-simulated grazing and number of pika) on aboveground biomass (AGB) in the Yellow River Source Zone from 2018 to 2020. AGB was estimated from drone images for 27 plots subject to three levels of each disturbance (none, moderate, and severe). The three mowing severities bear a close relationship with AGB and its annual change. The effects of pika disturbance on AGB change were overwhelmed by the significantly different AGB at different mowing severities (-.471 r < -.368), but can still be identified by inspecting each mowing intensity (-.884 r < -.626). The impact of severe mowing on AGB loss was more profound than that of severe pika disturbance in heavily disturbed plots, and the joint effects of both severe disturbances had the most impacts on AGB loss. However, pika disturbance made little difference to AGB change in the moderate and non-mowed plots. Mowing intensity weakens the relationship between pika population and AGB change, but pika disturbance hardly affects the relationship between mowing severity and AGB change. The effects of both disturbances on AGB were further complexified by the change in monthly mean temperature. Results indicate that reducing mowing intensity is more effective than controlling pika population in efforts to achieve sustainable grazing of heavily disturbed grassland. C1 [Shi, Yan; Gao, Jay; Brierley, Gary] Univ Auckland, Sch Environm, Auckland, New Zealand. [Li, Xilai; Li, Jiexia] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. RP Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. EM xilai-li@163.com TC 3 Z9 3 PD MAR PY 2022 VL 12 IS 3 AR e8640 DI 10.1002/ece3.8640 UT WOS:000774771100001 DA 2023-03-23 ER PT J AU Xu, YQ Xiao, FJ Liao, YM AF Xu, Yuqing Xiao, Fengjin Liao, Yaoming TI Assessment of Grassland Ecosystem Service Value in Response to Climate Change in China SO DIVERSITY-BASEL DT Article AB The assessment of ecosystem services provides an intuitive source of information on the benefits humans derive from ecosystems. The equivalent factor method was applied to calculate the ecosystem service value (ESV) in combination with net primary productivity (NPP) calculated by the process-based Carnegie-Ames-Stanford approach (CASA) model. This study evaluated grassland ESV and its spatial evolution characteristics in China from 2001 to 2020 and revealed the impact of climate factors. For 2001-2020, the annual grassland ESV ranged from 1.17 x 10(12) to 1.51 x 10(12) yuan (renminbi, China yuan-the same below; $0.15 x 10(12)-$0.20 x 10(12), US dollar), with an average of 1.37 x 10(12) yuan ($0.18 x 10(12)). The spatial pattern of ESV per unit area of grassland was notably characterized by an increase from northwest to southeast. However, the value of grassland ecosystem services was relatively large (exceeding 10 x 10(6) yuan; $1.30 x 10(6)) in northern and western provinces and was the lowest (less than 0.2 x 10(6) yuan; $0.03 x 10(6)) in eastern and southern provinces. In the last 20 years, grassland ESV has increased in most areas of China and has decreased only in some western and northern areas. Compared with the first 10 years, the average ESV of grassland in most areas increased in the last 10 years, usually by less than 20%. However, it decreased in the western and northern parts of China, mainly concentrated in the alpine meadow and alpine grassland of the Qinghai-Tibet Plateau and the grassland around the Yili region of Xinjiang. Precipitation was the main regulating factor of grassland ESV and had a positive impact in 79% grassland areas, especially in northern China. Evapotranspiration and sunshine hours exhibited a marginal impact on ESV, but temperature and relative humidity had no significant effect. Overall, this study contributes to exploring the spatiotemporal patterns of grassland ecosystem service value and the impact of climate factors in China, thereby providing reliable guidance for grassland ecosystem management. C1 [Xu, Yuqing; Xiao, Fengjin; Liao, Yaoming] China Meteorol Adm, Natl Climate Ctr, Beijing 100081, Peoples R China. RP Xu, YQ (通讯作者)，China Meteorol Adm, Natl Climate Ctr, Beijing 100081, Peoples R China. EM xuyq@cma.gov.cn; xiaofj@cma.gov.cn; lymzxr@cma.gov.cn TC 5 Z9 5 PD MAR PY 2022 VL 14 IS 3 AR 160 DI 10.3390/d14030160 UT WOS:000775596900001 DA 2023-03-23 ER PT J AU Zhao, L Liu, ZH Hu, YM Zhou, W Peng, YP Ma, T Liu, L Li, SH Wang, LY Mao, XY AF Zhao, Li Liu, Zhenhua Hu, Yueming Zhou, Wu Peng, Yiping Ma, Tao Liu, Luo Li, Shihua Wang, Liya Mao, Xiaoyun TI Evaluation of Reasonable Stocking Rate Based on the Relative Contribution of Climate Change and Grazing Activities to the Productivity of Alpine Grasslands in Qinghai Province SO REMOTE SENSING DT Article AB An accurate assessment of the stocking rate is crucial for maintaining the stable function and the sustainable use of the alpine grassland ecosystem. A new scenario design method to evaluate the reasonable stocking rate is presented in the current work. First, climate change is quantified by potential net primary productivity (NPPp) and measured by adopting the Zhou Guangsheng model, and the NPP generated by anthropogenic activities (NPPh) is estimated by the distinction between NPPp and actual NPP (NPPa) calculated with the application of the Carnegie-Ames-Stanford Approach (CASA) model. Second, using the NPPh and actual grassland productivity consumed by livestock (NPPac), the reasonable stocking rate is obtained. Finally, the driving factors of NPP change in alpine grassland and the reasonable stocking rate are clarified in Qinghai Province during 2005-2018. The results reveal that the temperature of alpine grassland in Qinghai Province has a slight upward trend from 2005 to 2018, and precipitation displays a downward trend. The overall NPPp of alpine grassland demonstrated a downward trend, and precipitation is regarded as the major influencing factor. In addition, the overall NPPh of alpine grassland exhibited a downward trend. The NPPa demonstrated an overall upward trend, where 58.32% of the regional NPPa is in a state of growth, and 41.68% of the regional NPPa is in a state of degradation. According to contribution analysis, anthropogenic activities provided the primary driving factor to promote the restoration of alpine grassland in Qinghai Province. Moreover, the stocking rate must be reduced in 60.77% of the alpine grasslands in Qinghai Province, mostly situated in the eastern and southwestern parts of Qinghai Province, and the other areas must not increase future stocking rates. The current study can theoretically and technically support the construction of Qinghai as the green organic agricultural and livestock product demonstration province and the creation of an ecological civilization highland. C1 [Zhao, Li; Liu, Zhenhua; Zhou, Wu; Peng, Yiping; Liu, Luo; Mao, Xiaoyun] South China Agr Univ, Coll Nat Resources & Environm, Guangzhou 510642, Peoples R China. [Hu, Yueming] Hainan Univ, Coll Trop Crops, Haikou 570228, Hainan, Peoples R China. [Hu, Yueming; Ma, Tao] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Hu, Yueming; Ma, Tao] South China Acad Nat Resources Sci & Technol, Guangzhou 510642, Peoples R China. [Li, Shihua] Univ Elect Sci & Technol China, Sch Resources & Environm, Chengdu 611731, Peoples R China. [Wang, Liya] Nat Resources Comprehens Invest & Monitoring Inst, Xining 810000, Peoples R China. RP Hu, YM (通讯作者)，Hainan Univ, Coll Trop Crops, Haikou 570228, Hainan, Peoples R China.; Hu, YM (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China.; Hu, YM (通讯作者)，South China Acad Nat Resources Sci & Technol, Guangzhou 510642, Peoples R China. EM zhaoli@stu.scau.edu.cn; zhenhua@scau.edu.cn; ymhu@scau.edu.cn; wuzhou@stu.scau.edu.cn; pengyp@stu.scau.edu.cn; 1989990003@qhu.edu.cn; liuluo@scau.edu.cn; lishihua@uestc.edu.cn; wt@stu.scau.edu.cn; xymao@scau.edu.cn TC 4 Z9 4 PD MAR PY 2022 VL 14 IS 6 AR 1455 DI 10.3390/rs14061455 UT WOS:000774401700001 DA 2023-03-23 ER PT J AU Zhou, W Li, HR Wen, SY Xie, LJ Wang, T Tian, YZ Yu, WP AF Zhou, Wei Li, Haoran Wen, Shiya Xie, Lijuan Wang, Ting Tian, Yongzhong Yu, Wenping TI Simulation of Soil Organic Carbon Content Based on Laboratory Spectrum in the Three-Rivers Source Region of China SO REMOTE SENSING DT Article AB Soil organic carbon (SOC) changes affect the land carbon cycle and are also closely related to climate change. Visible-near infrared spectroscopy (Vis-NIRS) has proven to be an effective tool in predicting soil properties. Spectral transformations are necessary to reduce noise and ensemble learning methods can improve the estimation accuracy of SOC. Yet, it is still unclear which is the optimal ensemble learning method exploiting the results of spectral transformations to accurately simulate SOC content changes in the Three-Rivers Source Region of China. In this study, 272 soil samples were collected and used to build the Vis-NIRS simulation models for SOC content. The ensemble learning was conducted by the building of stack models. Sixteen combinations were produced by eight spectral transformations (S-G, LR, MSC, CR, FD, LRFD, MSCFD and CRFD) and two machine learning models of RF and XGBoost. Then, the prediction results of these 16 combinations were used to build the first-step stack models (Stack1, Stack2, Stack3). The next-step stack models (Stack4, Stack5, Stack6) were then made after the input variables were optimized based on the threshold of the feature importance of the first-step stack models (importance > 0.05). The results in this study showed that the stack models method obtained higher accuracy than the single model and transformations method. Among the six stack models, Stack 6 (5 selected combinations + XGBoost) showed the best simulation performance (RMSE = 7.3511, R-2 = 0.8963, and RPD = 3.0139, RPIQ = 3.339), and obtained higher accuracy than Stack3 (16 combinations + XGBoost). Overall, our results suggested that the ensemble learning of spectral transformations and simulation models can improve the estimation accuracy of the SOC content. This study can provide useful suggestions for the high-precision estimation of SOC in the alpine ecosystem. C1 [Zhou, Wei; Li, Haoran; Wen, Shiya; Wang, Ting; Tian, Yongzhong; Yu, Wenping] Southwest Univ, Sch Geog Sci, Chongqing Jinfo Mt Karst Ecosyst Natl Observat &, Chongqing 400715, Peoples R China. [Zhou, Wei] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China. [Li, Haoran; Xie, Lijuan] Chongqing Jiaotong Univ, Dept Geog & Land & Resources, Chongqing 400074, Peoples R China. RP Li, HR (通讯作者)，Southwest Univ, Sch Geog Sci, Chongqing Jinfo Mt Karst Ecosyst Natl Observat &, Chongqing 400715, Peoples R China.; Li, HR (通讯作者)，Chongqing Jiaotong Univ, Dept Geog & Land & Resources, Chongqing 400074, Peoples R China. EM zw20201109@swu.edu.cn; lhr97@mails.cqjtu.edu.cn; meinwsy@email.swu.edu.cn; xielijuan@piesat.cn; swuwt230@email.swu.edu.cn; tyzlf@swu.edu.cn; ywpgis2005@swu.edu.cn TC 1 Z9 1 PD MAR PY 2022 VL 14 IS 6 AR 1521 DI 10.3390/rs14061521 UT WOS:000774654600001 DA 2023-03-23 ER PT J AU Shi, GX Yang, Y Liu, YJ Uwamungu, JY Liu, YM Wang, YB Feng, HY Yao, BQ Zhou, HK AF Shi, Guoxi Yang, Yue Liu, Yongjun Uwamungu, Jean Yves Liu, Yanmei Wang, Yibo Feng, Huyuan Yao, Buqing Zhou, Huakun TI Effect of Elymus nutans on the assemblage of arbuscular mycorrhizal fungal communities enhanced by soil available nitrogen in the restoration succession of revegetated grassland on the Qinghai-Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB The succession of arbuscular mycorrhizal fungi (AMF) communities during ecosystem development has received widespread attention, but the ecological mechanism that drives the succession of AMF communities during the restoration process in alpine meadow ecosystems remains unclear. Here, we treated 'Black Beach' (severely degraded alpine meadow) as the baseline for restoration (0 year), and selected the revegetated grassland of Elymus nutans with different planting times (3, 7, 10, and 14 years) to analyze the species composition of the AMF community in mixed roots (at the whole-plant-community scale) and in E. nutans roots (at the single-plant-species scale). A total of 46 AMF phylotypes (mixed roots: 44; E. nutans roots: 46) were identified in both root systems, predominantly belonging to Glomeraceae. AMF species richness showed a single-peak curve change across the restoration time and reached its peak at 3 years in both root systems. In mixed roots, the soil available nitrogen not only directly changed the AMF species composition but also indirectly changed the AMF species composition through plant richness. In the E. nutans roots, only the soil available nitrogen drove changes in AMF species composition through changes in plant richness. Our results indicate that E. nutans, a key species in the restoration process of revegetated grassland, can enhance its regulation to assemble the AMF community through soil available nitrogen at the two research scales, suggesting that the scientific management of soil nitrogen availability during restoration succession could strengthen the mutual symbiosis of 'plant-AMF,' thereby retarding the occurrence of secondary degradation of revegetated grassland. C1 [Shi, Guoxi; Uwamungu, Jean Yves; Liu, Yanmei; Wang, Yibo] Tianshui Normal Univ, Coll Bioengn & Biotechnol, Key Lab Utilizat Agr Solid Waste Resources, Tianshui, Peoples R China. [Shi, Guoxi; Yao, Buqing; Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining, Peoples R China. [Yang, Yue; Liu, Yongjun; Feng, Huyuan] Lanzhou Univ, Sch Life Sci, MOE Key Lab Cell Act & Stress Adaptat, Lanzhou, Peoples R China. RP Yao, BQ; Zhou, HK (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xinning Rd 23, Xining 810008, Peoples R China. EM bqyao@nwipb.cas.cn; hkzhou@nwipb.cas.cn TC 2 Z9 2 PD APR 15 PY 2022 VL 33 IS 6 BP 931 EP 944 DI 10.1002/ldr.4201 EA FEB 2022 UT WOS:000762017200001 DA 2023-03-23 ER PT J AU Cao, PX Liu, YX Ma, HM Zhao, N Chen, ST Xu, GQ Liu, X AF Cao, Peng-xi Liu, Yixuan Ma, Hong-mei Zhao, Ning Chen, Shu-ting Xu, Guo-qi Liu, Xing TI Fungal Diversity in the Soil of the Oxytropis glacialis Root System on the Qinghai-Tibet Plateau SO FRONTIERS IN MICROBIOLOGY DT Article AB Because of swainonine-producing endophytic fungal, Oxytropis glacialis is one of the main poisonous weeds in the alpine grassland and desert grassland of the Qinghai-Tibet Plateau (QTP). It has a severe impact on grassland degradation on the QTP. In this manuscript, the Internally Transcribed Spacer (ITS) region of fungal communities in the soil of the O. glacialis root system was sequenced by high-throughput sequencing and analyzed by bioinformatics methods. The physical and chemical properties of the soil samples were analyzed in combination with the fungal diversity and its relationship with the soil physical and chemical factors. The results showed that the soil fungal community in the O. glacialis root system are rich in diversity in different ecological environments and are most affected by the soil pH value and organic matter. The swainonine-producing fungal Embellisia oxytropis was first detected in the soil of the O. glacialis root system. This finding provides data to support the next step in demonstrating the horizontal spread of swainone-producing fungal from O. glacialis to soil. In addition, a stable network of core flora has a facilitating effect on the formation of O. glacialis as a dominant species in alpine ecosystems. C1 [Cao, Peng-xi; Liu, Yixuan; Ma, Hong-mei; Zhao, Ning; Chen, Shu-ting; Xu, Guo-qi; Liu, Xing] Tibet Univ, Res Ctr Ecol, Ecol Field Stn Real Time Monitoring Ctr, Lhasa, Peoples R China. [Cao, Peng-xi; Liu, Yixuan; Ma, Hong-mei; Zhao, Ning; Chen, Shu-ting; Xu, Guo-qi; Liu, Xing] Tibet Univ, Res Ctr Ecol & Environm Qinghai Tibetan Plateau, Lab Adaptat & Evolut Plateau Biota Extreme Enviro, Lhasa, Peoples R China. [Cao, Peng-xi; Liu, Yixuan; Liu, Xing] Wuhan Univ, Coll Life Sci, Wuhan, Peoples R China. RP Liu, YX; Liu, X (通讯作者)，Tibet Univ, Res Ctr Ecol, Ecol Field Stn Real Time Monitoring Ctr, Lhasa, Peoples R China.; Liu, YX; Liu, X (通讯作者)，Tibet Univ, Res Ctr Ecol & Environm Qinghai Tibetan Plateau, Lab Adaptat & Evolut Plateau Biota Extreme Enviro, Lhasa, Peoples R China.; Liu, YX; Liu, X (通讯作者)，Wuhan Univ, Coll Life Sci, Wuhan, Peoples R China. EM yixuan.liu@foxmail.com; xingliu@whu.edu.cn TC 0 Z9 0 PD FEB 24 PY 2022 VL 13 AR 831783 DI 10.3389/fmicb.2022.831783 UT WOS:000766678200001 DA 2023-03-23 ER PT J AU Wang, XY He, XC Price, M He, QY Zhang, P Ran, JH Wu, YJ AF Wang, Xiaoyi He, Xingcheng Price, Megan He, Qianyun Zhang, Pei Ran, Jianghong Wu, Yongjie TI Epigeic arthropod community changes in response to livestock-caused alpine grassland degradation on the eastern Qinghai-Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB As one of the most important ecosystems, grassland ecosystems maintain an abundance of flora and fauna, and provide humans with rich resources. The structure and function of most grassland ecosystems around the world have been significantly affected by human activity. The overgrazing of livestock and their feces has caused grassland degradation and flora and fauna losses. However, we know little about the relationship between grassland degradation, livestock feces and the arthropod community. In this study, we conducted surveys of the epigeic arthropod community in alpine grassland of the Zoige wetlands in eastern Qinghai-Tibetan Plateau, China. We used ANOVA, multiple linear regression and model-averaging to explore how grassland degradation and livestock feces affected epigeic arthropods community. We found that together grassland degradation and season differently affected taxonomic richness, abundance and different feeding groups of the epigeic arthropod community. Because of the influence of temperature on the epigeic arthropod, the taxonomic richness and abundance of epigeic arthropod community fluctuated dramatically among seasons. Epigeic arthropod community diversity had a significant positive correlation with plant height of all species and Compositae percentage cover in most levels of degradation. The amount of sheep feces had a significant negative correlation with taxonomic richness and abundance of the epigeic arthropod community, because overgrazing sheep reduces the availability of resources and the suitability of micro-habitats for epigeic arthropods. Our study found that moderate levels of disturbance can increase the richness and abundance of epigeic arthropod community over a short period of time. C1 [Wang, Xiaoyi; He, Xingcheng; Price, Megan; He, Qianyun; Zhang, Pei; Ran, Jianghong; Wu, Yongjie] Sichuan Univ, Coll Life Sci, Minist Educ, Key Lab Bioresources & Ecoenvironm, Chengdu 610064, Sichuan, Peoples R China. [Wang, Xiaoyi; He, Xingcheng; Price, Megan; He, Qianyun; Zhang, Pei; Ran, Jianghong; Wu, Yongjie] Sichuan Univ, Coll Life Sci, Sichuan Key Lab Conservat Biol Endangered Wildlif, Chengdu 610064, Sichuan, Peoples R China. RP Wu, YJ (通讯作者)，Sichuan Univ, Coll Life Sci, Minist Educ, Key Lab Bioresources & Ecoenvironm, Chengdu 610064, Sichuan, Peoples R China. EM may1992@aliyun.com; hexingcheng@outlook.com; meganprice@scu.edu.cn; 987801367@qq.com; ritazhang1991@gmail.com; rjhong-01@163.com; wuyongjie@scu.edu.cn TC 0 Z9 1 PD JUN PY 2022 VL 35 AR e02062 DI 10.1016/j.gecco.2022.e02062 EA FEB 2022 UT WOS:000761018100002 DA 2023-03-23 ER PT J AU Wang, PY Wang, JS Elberling, B Yang, L Chen, WN Song, L Yan, YJ Wang, S Pan, JX He, YL Niu, SL AF Wang, Peiyan Wang, Jinsong Elberling, Bo Yang, Lu Chen, Weinan Song, Lei Yan, Yingjie Wang, Song Pan, Junxiao He, Yunlong Niu, Shuli TI Increased annual methane uptake driven by warmer winters in an alpine meadow SO GLOBAL CHANGE BIOLOGY DT Article AB Pronounced nongrowing season warming and changes in soil freeze-thaw (F-T) cycles can dramatically alter net methane (CH4) exchange rates between soils and the atmosphere. However, the magnitudes and drivers of warming impacts on CH4 uptake in different stages of the F-T cycle are poorly understood in cold alpine ecosystems, which have been found to be a net sink of atmospheric CH4. Here, we reported a year-round ecosystem daily CH4 uptake in an alpine meadow on the Qinghai-Tibetan Plateau after a 5-year warming experiment that included a control, a low-level warming treatment (+2.4celcius at 5 cm soil depth), and a high-level warming treatment (+4.5celcius at 5 cm soil depth). We found that warming shortened the F-T cycle under the low-level warming and soils did not freeze under the high-level warming. Although both warming treatments increased the mean CH4 uptake rate, only the high-level warming significantly increased annual CH4 uptake compared to the control. The warming-induced stimulation of CH4 uptake mainly occurred in the cold season, which was mostly during spring thaw under low-level warming and during the frozen winter under high-level warming due to a longer period with thawed soil. We also found that warming significantly stimulated daily CH4 uptake mainly by reducing near-surface soil water content in the warm season, whereas both soil water content and temperature controlled daily CH4 uptake in different ways during the autumn freeze, frozen winter, and spring thaw periods of the control. Our study revealed a strong warming effect on CH4 uptake during the entire F-T cycle in the alpine meadow, especially the unfrozen winter. Our results also suggested the important roles of soil pH, available phosphorus, and methanotroph abundance in regulating annual CH4 uptake in response to warming, which should be incorporated into biogeochemical models for accurately forecasting CH4 fluxes under future climate scenarios. C1 [Wang, Peiyan; Wang, Jinsong; Yang, Lu; Chen, Weinan; Song, Lei; Yan, Yingjie; Wang, Song; Pan, Junxiao; He, Yunlong; Niu, Shuli] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Elberling, Bo] Univ Copenhagen, Dept Geosci & Nat Resource Management, Ctr Permafrost CENPERM, Copenhagen, Denmark. [Chen, Weinan; Song, Lei; Yan, Yingjie; Wang, Song; Niu, Shuli] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. RP Wang, JS; Niu, SL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. EM wangjinsong@igsnrr.ac.cn; sniu@igsnrr.ac.cn TC 3 Z9 3 PD MAY PY 2022 VL 28 IS 10 BP 3246 EP 3259 DI 10.1111/gcb.16120 EA FEB 2022 UT WOS:000759240100001 DA 2023-03-23 ER PT J AU Pan, DR Yan, HW Li, Q Liu, DY Liu, XN Zhang, DG Han, TH Sun, B Jiang, JC AF Pan Dongrong Yan Haowen Li Qiang Liu Danyang Liu Xiaoni Zhang Degang Han Tianhu Sun Bin Jiang Jiachang TI Loss of grassland ecosystem service values based on potential vegetation in China SO RANGELAND JOURNAL DT Article AB Grassland resources in China have diverse categories and span extensive areas. Existing studies have estimated the value of ecosystem services in China at different scales, but there are few reports on the potential loss of grassland ecosystem services in China. On the basis of the class-level compatibility of the two existing grassland classification systems, this study separately estimated the ecosystem service valves (ESVs) of Chinese potential grassland ecosystems (Comprehensive Sequential Classification System, CSCS) and existing grassland ecosystems (Vegetation Habitatology Classification System, VHCS). In addition, we also calculated the loss of ESVs between the two grassland classification systems and further analysed the reasons for the loss. The results are as follows: (1) the total amount of ESVs provided by the existing grassland in China was 64 929.87 x 10(8) Ren Min Bi (RMB) per year, in which lowland meadow and alpine meadow provide higher ESVs than the other 16 grassland classes; (2) the total ESV of Chinese potential grasslands was 83 632.88 x 10(8) RMB per year, of which IE29 (frigid temperate humid tundra, alpine meadow) and IF36 (frigid perhumid rain tundra, alpine meadow) contributed most to the total ESV (16.9%); (3) the ESVs of grassland in China decreased by 18 703.01 x 10(8) RMB per year compared with the potential value; the ESV loss mainly occurred in areas where the original grassland decreased and the secondary grassland increased; and (4) anthropogenic disturbances such as grazing, felling and indiscriminate cultivation and climate change are the main reasons for loss of ESV owing to grassland degradation. C1 [Pan Dongrong; Yan Haowen] Lanzhou Jiaotong Univ, Fac Geomat, Lanzhou 730070, Peoples R China. [Li Qiang; Liu Danyang; Liu Xiaoni; Zhang Degang] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Peoples R China. [Pan Dongrong; Han Tianhu; Sun Bin; Jiang Jiachang] Gansu Grassland Tech Extens Stn, Lanzhou 730010, Peoples R China. RP Liu, XN (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Peoples R China. EM liuxn@gsau.edu.cn TC 0 Z9 0 PY 2021 VL 43 IS 6 BP 363 EP 375 DI 10.1071/RJ20118 EA FEB 2022 UT WOS:000755550800001 DA 2023-03-23 ER PT J AU Hu, JA Nan, ZT Ji, HL AF Hu, Jianan Nan, Zhuotong Ji, Hailong TI Spatiotemporal Characteristics of NPP Changes in Frozen Ground Areas of the Three-River Headwaters Region, China: A Regional Modeling Perspective SO FRONTIERS IN EARTH SCIENCE DT Article AB Permafrost degradation triggered by climate warming can disturb alpine ecosystem stability and further influence net primary productivity (NPP). Known as the "water tower of China", the Three-River Headwaters Region (TRHR) on the eastern Qinghai-Tibet plateau (QTP), is characterized by a fragile alpine meadow ecosystem underlain by large areas of unstable permafrost and has been subject to rapid climate change in recent decades. Despite some site-specific studies, the spatial and temporal changes in NPP in the different frozen ground zones across the TRHR associated with climate change remain poorly understood. In this study, a physically explicit Noah land surface model with multi-parameterization options (Noah-MP) was employed to simulate NPP changes on the TRHR during 1989-2018. The simulation was performed with a spatial resolution of 0.1 degrees and a temporal resolution of 3h, and validated at two sites with meteorological and flux observations. The results show that the average NPP was estimated to be 299.7 g C m(-2) yr(-1) in the seasonally frozen ground (SFG) zone and 198.5 g C m(-2) yr(-1) in the permafrost zone. NPP in the TRHR increased at a rate of 1.09 g C m(-2) yr(-2) during 1989-2018, increasing in 1989-2003 and then decreasing in subsequent years. The NPP in permafrost area increased at a rate of 1.43 g C m(-2) yr(-2) during 1989-2018, which is much higher than the rate of change in NPP in the SFG area (0.67 g C m(-2) yr(-2)). Permafrost degradation has complicated ecosystem implications. In areas where permafrost degradation has occurred, both increasing and decreasing changes in NPP have been observed. C1 [Hu, Jianan; Nan, Zhuotong; Ji, Hailong] Nanjing Normal Univ, Key Lab, Minist Educ Virtual Geog Environm, Nanjing, Peoples R China. [Nan, Zhuotong] Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing, Peoples R China. RP Nan, ZT (通讯作者)，Nanjing Normal Univ, Key Lab, Minist Educ Virtual Geog Environm, Nanjing, Peoples R China.; Nan, ZT (通讯作者)，Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing, Peoples R China. EM nanzt@njnu.edu.cn TC 2 Z9 2 PD FEB 14 PY 2022 VL 10 AR 838558 DI 10.3389/feart.2022.838558 UT WOS:000762002500001 DA 2023-03-23 ER PT J AU Wei, JQ Li, XY Liu, L Christensen, TR Jiang, ZY Ma, YJ Wu, XC Yao, HY Lopez-Blanco, E AF Wei, Junqi Li, Xiaoyan Liu, Lei Christensen, Torben Rojle Jiang, Zhiyun Ma, Yujun Wu, Xiuchen Yao, Hongyun Lopez-Blanco, Efren TI Radiation, soil water content, and temperature effects on carbon cycling in an alpine swamp meadow of the northeastern Qinghai-Tibetan Plateau SO BIOGEOSCIENCES DT Article AB Predicted intensified climate warming will likely alter the ecosystem net carbon (C) uptake of the Qinghai-Tibetan Plateau (QTP). Variations in C sink-source responses to climate warming have been linked to water availability; however, the mechanisms by which net C uptake responds to soil water content in saturated swamp meadow ecosystems remain unclear. To explore how soil moisture and other environmental drivers modulate net C uptake in the QTP, field measurements were conducted using the eddy covariance technique in 2014, 2015, 2017, and 2018. The alpine swamp meadow presented in this study was a persistent and strong C sink of CO2 (-168.0 +/- 62.5 g C m(-2) yr(-1), average +/- standard deviation) across the entire 4-year study period. A random forest machine-learning analysis suggested that the diurnal and seasonal variations of net ecosystem exchange (NEE) and gross primary productivity (GPP) were regulated by temperature and net radiation. Ecosystem respiration (Re), however, was found mainly regulated by the variability of soil water content (SWC) at different temporal aggregations, followed by temperature, the second contributing driver. We further explored how Re is controlled by nearly saturated soil moisture and temperature comparing two different periods featuring almost identical temperatures and significant differences on SWC and vice versa. Our data suggest that, despite the relatively abundant water supply, periods with a substantial decrease in SWC or increase in temperature produced higher Re and therefore weakened the C sink strength. Our results reveal that nearly saturated soil conditions during the growing seasons can help maintain lower ecosystem respiration rates and thus enhance the overall C sequestration capacity in this alpine swamp meadow. We argue that soil respiration and subsequent ecosystem C sink magnitude in alpine swamp meadows could likely be affected by future changes in soil hydrological conditions caused by permafrost degradation or accelerated thawing-freezing cycling due to climate warming. C1 [Wei, Junqi; Li, Xiaoyan; Wu, Xiuchen; Yao, Hongyun] Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Wei, Junqi; Li, Xiaoyan; Wu, Xiuchen; Yao, Hongyun] Beijing Normal Univ, Fac Geog Sci, Sch Nat Resources, Beijing 100875, Peoples R China. [Li, Xiaoyan] Peoples Govt Qinghai Prov, Acad Plateau Sci & Sustainabil, Xining 810008, Peoples R China. [Li, Xiaoyan] Beijing Normal Univ, Xining 810008, Peoples R China. [Li, Xiaoyan] Qinghai Normal Univ, Xining 810008, Peoples R China. [Li, Xiaoyan] Qinghai Normal Univ, Key Lab Tibetan Plateau Land Surface Proc & Ecol, Minist Educ, Xining 810016, Peoples R China. [Liu, Lei] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Liu, Lei] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Christensen, Torben Rojle; Lopez-Blanco, Efren] Aarhus Univ, Arctic Res Ctr, Dept Ecosci, DK-4000 Roskilde, Denmark. [Christensen, Torben Rojle] Univ Oulu, Oulanka Res Stn, Oulu, Finland. [Jiang, Zhiyun] South China Normal Univ, Sch Geog, Guangzhou 510631, Peoples R China. [Ma, Yujun] Sun Yat Sen Univ, Sch Geog & Planning, Guangzhou 510275, Peoples R China. [Lopez-Blanco, Efren] Greenland Inst Nat Resources, Dept Environm & Minerals, Nuuk 3900, Greenland. RP Li, XY (通讯作者)，Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China.; Li, XY (通讯作者)，Beijing Normal Univ, Fac Geog Sci, Sch Nat Resources, Beijing 100875, Peoples R China.; Li, XY (通讯作者)，Peoples Govt Qinghai Prov, Acad Plateau Sci & Sustainabil, Xining 810008, Peoples R China.; Li, XY (通讯作者)，Beijing Normal Univ, Xining 810008, Peoples R China.; Li, XY (通讯作者)，Qinghai Normal Univ, Xining 810008, Peoples R China.; Li, XY (通讯作者)，Qinghai Normal Univ, Key Lab Tibetan Plateau Land Surface Proc & Ecol, Minist Educ, Xining 810016, Peoples R China. EM xyli@bnu.edu.cn TC 2 Z9 2 PD FEB 10 PY 2022 VL 19 IS 3 BP 861 EP 875 DI 10.5194/bg-19-861-2022 UT WOS:000758151400001 DA 2023-03-23 ER PT J AU Li, CY Li, XL Su, XX Yang, YW Li, HL AF Li, C. Y. Li, X. L. Su, X. X. Yang, Y. W. Li, H. L. TI Effects of Alpine Wetland Degradation on Soil Microbial Structure and Diversity on the Qinghai Tibet Plateau SO EURASIAN SOIL SCIENCE DT Article AB The characteristics of microbial structure in different soil degradation stages caused by the drought processes from wetland to meadow on the Qinghai Tibet Plateau were analyzed. The composition and diversity of soil bacteria and fungi were also analyzed by using high-throughput sequencing technology. The results showed that Proteobacteria was the highest abundance among bacteria, and Ascomycota was the highest among fungi. The degradation transition from alpine wetland to alpine meadow had insignificantly affected on the dominant bacteria, but had significantly affected on Gracilibacteriae and Ignavibacteriae bacterial phyla (P < 0.05), which characterized low abundance. The relative abundance of the dominant, fungal phyla Mortierellomycota (P < 0.05) significantly increased in soils along the degradation gradient. There was no significant difference between soil bacteria and fungi for Alpha diversity in different soil degradation stages. Beta diversity was found to be significant difference in soil bacterial structure for alpine swamp wetland and alpine meadow. Soil pH, water content, total organic carbon (TOC), total nitrogen (TN) decreased significantly (P < 0.05) with the degradation stages. RDA analysis showed that TN and TOC achieved the highest effect on the bacteria number expressed as operational taxonomic units and their Shannon index, moreover soil water content significantly affected on fungi number and Shannon index. TN and bacterial number had a significant positive correlation (P < 0.05). The relative abundance of Gracilibacteriae, Ignavibacteriae and Elusimicrobiae, which are beneficial to soil C and N contents and that Gemmatimonadetes are beneficial to N fixation, decreased in the drought processes of alpine wetland. This result could increase the relative abundance of the fungi phylum of Mortierellomycota, and might decrease the soil microbial diversity. C1 [Li, C. Y.; Li, X. L.; Yang, Y. W.; Li, H. L.] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Li, C. Y.; Li, X. L.; Su, X. X.; Yang, Y. W.] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Li, X. L.] Qinghai Univ, Qinghai Guangdong Joint Lab Nat Resources Monitor, Xining 810016, Peoples R China. RP Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China.; Li, XL (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China.; Li, XL (通讯作者)，Qinghai Univ, Qinghai Guangdong Joint Lab Nat Resources Monitor, Xining 810016, Peoples R China. EM xilai-li@163.com TC 4 Z9 4 PD DEC PY 2021 VL 54 IS SUPPL 1 SU 1 BP S33 EP S41 DI 10.1134/S1064229322030097 EA FEB 2022 UT WOS:000753739700004 DA 2023-03-23 ER PT J AU Li, JY Charles, LS Yang, ZL Du, GZ Fu, SL AF Li, Junyong Charles, Lachlan S. Yang, Zhongling Du, Guozhen Fu, Shenglei TI Differential Mechanisms Drive Species Loss Under Artificial Shade and Fertilization in the Alpine Meadow of the Tibetan Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB Fertilization is an effective management strategy to promote community biomass but can simultaneously reduce species diversity in many grassland systems. Shifts in competition for resources have been proposed to explain the decline in plant species diversity due to fertilization, yet the underlying mechanism driving species loss remains controversial. This uncertainty may be driven by variation in aboveground and belowground resource availability. However, experiments simultaneously manipulating both light availability and soil nutrients are rare. Using a 6-year field experiment to manipulate light availability (via shade cloth) and soil nutrients (via fertilizer addition), we tested this resource competition hypothesis in a species-rich alpine meadow by examining the variation of species traits associated with the capacity of light acquisition within these treatments. Our results showed that artificial shade decreased community biomass accumulation whereas fertilization increased it. In contrast, both shade and fertilization reduced species diversity. Extinction of non-Gramineae species (e.g., Fabaceae and Cyperaceae) was the main reason for species diversity decline. Species loss can be explained by the limitation of light availability and predicted by species traits associated with light acquisition capability under fertilization and low light tolerance under artificial shade. Specifically, fertilization eliminated species with lower stature and artificial shade exterminated species with the higher light compensation point (LCP). The findings suggest that light availability is consistently important for plant growth and that low competitiveness for light under fertilization and intolerance of low light conditions under artificial shade trigger species loss process in the alpine meadow. Our experiment helps clarify the mechanisms of how artificial shade and fertilization decreased species diversity and highlight that LCP, which tends to be neglected by most of the studies, is one of the vital drivers in determining species coexistence. C1 [Li, Junyong; Fu, Shenglei] Henan Univ, Dabieshan Natl Observat & Res Field Stn Forest Ec, Kaifeng, Peoples R China. [Li, Junyong; Fu, Shenglei] Henan Univ, Coll Geog & Environm Sci, Kaifeng, Peoples R China. [Li, Junyong; Yang, Zhongling] Henan Univ, Sch Life Sci, Kaifeng, Peoples R China. [Charles, Lachlan S.] Terr Ecosyst Res Network, Indooroopilly, Qld, Australia. [Du, Guozhen] Lanzhou Univ, Sch Life Sci, Lanzhou, Peoples R China. RP Fu, SL (通讯作者)，Henan Univ, Dabieshan Natl Observat & Res Field Stn Forest Ec, Kaifeng, Peoples R China.; Fu, SL (通讯作者)，Henan Univ, Coll Geog & Environm Sci, Kaifeng, Peoples R China.; Yang, ZL (通讯作者)，Henan Univ, Sch Life Sci, Kaifeng, Peoples R China. EM yang_zhl06@126.com; fsl@henu.edu.cn TC 14 Z9 14 PD FEB 8 PY 2022 VL 13 AR 832473 DI 10.3389/fpls.2022.832473 UT WOS:000760482400001 DA 2023-03-23 ER PT J AU Han, WY Chen, L Su, XK Liu, D Jin, TT Shi, SL Li, T Liu, GH AF Han, Wangya Chen, Li Su, Xukun Liu, Dan Jin, Tiantian Shi, Songlin Li, Tao Liu, Guohua TI Effects of Soil Physico-Chemical Properties on Plant Species Diversity Along an Elevation Gradient Over Alpine Grassland on the Qinghai-Tibetan Plateau, China SO FRONTIERS IN PLANT SCIENCE DT Article AB Elevation gradient can reflect the effects of soil physico-chemical properties on plant species diversity. Alpine grassland on the QTP has suffered from a serious decline in plant species diversity. In this study, we investigated 112 sites recording plant community characteristics and collecting soil samples along an elevation gradient (3,500-5,200 m asl) in alpine meadow on the QTP. We analyzed the effects of soil physico-chemical properties on plant species composition and diversity by canonical ordination and spatial regression along an elevation gradient. The results showed that species richness of the overall plant communities decreased with the increasing elevation, and the Simpson dissimilarity index (beta(sim)) had a maximum at low elevation (3,500-4,000 m) with the value of 0.37. Soil available nitrogen content was the primary soil parameter affecting plant species composition and diversity in alpine grassland. The effect of soil available nitrogen content on plant species richness varied at different elevations. For Gramineae plants (G), plant species richness declined with the increase in soil available nitrogen content at low elevation (3,500-4,000 m), but rose at middle elevation (4,000-4,500 m). Soil available nitrogen content had a more significant limiting effect on species richness at high elevation (>4,500 m). These findings increase our understanding about the drivers of plant species diversity changes in alpine grassland on the QTP, and will provide insights into grassland restoration and sustainable management. C1 [Han, Wangya] Nanjing Univ Informat Sci & Technol, Sch Appl Meteorol, Inst Ecol, Jiangsu Key Lab Agr Meteorol, Nanjing, Peoples R China. [Han, Wangya; Chen, Li; Su, Xukun; Li, Tao; Liu, Guohua] Chinese Acad Sci, State Key Lab Urban & Reg Ecol, Res Ctr Ecoenvironm Sci, Beijing, Peoples R China. [Chen, Li] Minist Sci & Technol, Torch High Technol Ind Dev Ctr, Beijing, Peoples R China. [Su, Xukun; Li, Tao; Liu, Guohua] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Liu, Dan] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu, Peoples R China. [Jin, Tiantian] China Inst Water Resources & Hydropower Res, Beijing, Peoples R China. [Shi, Songlin] Chengdu Univ Technol, Coll Tourism & Urban Rural Planning, Chengdu, Peoples R China. RP Liu, GH (通讯作者)，Chinese Acad Sci, State Key Lab Urban & Reg Ecol, Res Ctr Ecoenvironm Sci, Beijing, Peoples R China.; Liu, GH (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. EM ghliu@rcees.ac.cn TC 5 Z9 5 PD FEB 4 PY 2022 VL 13 AR 822268 DI 10.3389/fpls.2022.822268 UT WOS:000760224300001 DA 2023-03-23 ER PT J AU Zhang, Y Zheng, QZ Gao, XX Ma, YD Liang, KM Yue, HT Huang, XX Wu, KT Wang, XR AF Zhang, Yong Zheng, Qiuzhu Gao, Xiaoxia Ma, Yandan Liang, Kemin Yue, Haitao Huang, Xiaoxia Wu, Kaiting Wang, Xiaorong TI Land Degradation Changes the Role of Above- and Belowground Competition in Regulating Plant Biomass Allocation in an Alpine Meadow SO FRONTIERS IN PLANT SCIENCE DT Article AB The allocation pattern of plant biomass presents the strategy of the plant community to adopt environmental changes, while the driver of biomass allocation is still unclear in degraded alpine grassland ecosystems. To explore the issue, this study investigated the shoot-to-root (R/S) ratio, plant aboveground traits, and root competition of three functional groups (i.e., grasses, sedges, and forbs) at three degradation levels (i.e., no obvious degradation, ND; moderate degradation, MD; and severe degradation, SD) in an alpine meadow in the eastern Qinghai-Tibetan Plateau. The relationships among plant aboveground traits, root competition, and R/S ratio were tested using the structural equation model (SEM). The results showed that the shoot and root biomass tended to decrease, but the R/S ratio of the plant community did not change along the degradation gradient. Plant height, lateral spread, and leaf length of most plant functional groups reduced, while leaf width and leaf area of most plant functional groups did not change along the degradation gradients. The root competition ability (presented as the fraction of root biomass in total biomass) of sedges in MD was the lowest, while that of grasses was the highest. The effects of aboveground competition on the R/S ratio were non-linear because of the different roles of plant height, lateral spread, and leaf area in regulating the R/S ratio along the degradation gradient. In contrast, the effects of belowground competition on the R/S ratio were linear because belowground competition promoted the R/S ratio, and the strength of this effect reduced along the degradation gradient. These results indicate that plant competition might be a critical factor to maintain the high R/S ratio in degraded alpine meadows. C1 [Zhang, Yong; Zheng, Qiuzhu; Ma, Yandan; Liang, Kemin; Yue, Haitao; Wu, Kaiting; Wang, Xiaorong] Southwest Forestry Univ, Yunnan Key Lab Plateau Wetland Conservat Restorat, Coll Wetlands, Kunming, Yunnan, Peoples R China. [Zhang, Yong; Zheng, Qiuzhu; Ma, Yandan; Liang, Kemin; Yue, Haitao; Wu, Kaiting; Wang, Xiaorong] Southwest Forestry Univ, Natl Plateau Wetlands Res Ctr, Kunming, Yunnan, Peoples R China. [Gao, Xiaoxia] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. [Huang, Xiaoxia] Yunnan Univ, Sch Earth Sci, Kunming, Yunnan, Peoples R China. RP Zhang, Y (通讯作者)，Southwest Forestry Univ, Yunnan Key Lab Plateau Wetland Conservat Restorat, Coll Wetlands, Kunming, Yunnan, Peoples R China.; Zhang, Y (通讯作者)，Southwest Forestry Univ, Natl Plateau Wetlands Res Ctr, Kunming, Yunnan, Peoples R China. EM zhy1902@126.com TC 2 Z9 2 PD FEB 3 PY 2022 VL 13 AR 822594 DI 10.3389/fpls.2022.822594 UT WOS:000759866000001 DA 2023-03-23 ER PT J AU Li, M Zhang, KR Yan, ZQ Liu, L Kang, EZ Kang, XM AF Li, Meng Zhang, Kerou Yan, Zhongqing Liu, Liang Kang, Enze Kang, Xiaoming TI Soil Water Content Shapes Microbial Community Along Gradients of Wetland Degradation on the Tibetan Plateau SO FRONTIERS IN MICROBIOLOGY DT Article AB Soil microbes are important components in element cycling and nutrient supply for the development of alpine ecosystems. However, the development of microbial community compositions and networks in the context of alpine wetland degradation is unclear. We applied high-throughput 16S rRNA gene amplicon sequencing to track changes in microbial communities along degradation gradients from typical alpine wetland (W), to wet meadow (WM), to typical meadow (M), to grassland (G), and to desert (D) in the Zoige alpine wetland region on the Tibetan Plateau. Soil water content (SWC) decreased as wetland degradation progressed (79.4 and 9.3% in W and D soils, respectively). Total organic carbon (TOC), total nitrogen (TN), and total phosphorus (TP) increased in the soils of WM, and then decreased with alpine wetlands degradation from WM to the soils of M, G, and D, respectively. Wetland degradation did not affect microbial community richness and diversity from W soils to WM, M, and G soils, but did affect richness and diversity in D soils. Microbial community structure was strongly affected by wetland degradation, mainly due to changes in SWC, TOC, TN, and TP. SWC was the primary soil physicochemical property influencing microbial community compositions and networks. In wetland degradation areas, Actinobacteriota, Acidobacteriota, Cholorflexi, and Proteovacteria closely interacted in the microbial network. Compared to soils of W, WM, and M, Actinobacteriota played an important role in the microbial co-occurrence network of the G and D soils. This research contributes to our understanding of how microbial community composition and networks change with varied soil properties during degradation of different alpine wetlands. C1 [Li, Meng; Zhang, Kerou; Yan, Zhongqing; Kang, Enze; Kang, Xiaoming] Chinese Acad Forestry, Inst Wetland Res, Beijing, Peoples R China. [Li, Meng; Zhang, Kerou; Yan, Zhongqing; Kang, Enze; Kang, Xiaoming] Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China. [Li, Meng; Zhang, Kerou; Yan, Zhongqing; Kang, Enze; Kang, Xiaoming] Tibetan Autonomous Prefecture Aba, Sichuan Zoige Wetland Ecosyst Res Stn, Ngawa, Sichuan, Peoples R China. [Liu, Liang] Natl Disaster Reduct Ctr China, Minist Emergency Management, Beijing, Peoples R China. [Liu, Liang] Satellite Applicat Ctr Disaster Reduct, Minist Emergency Management, Beijing, Peoples R China. RP Kang, XM (通讯作者)，Chinese Acad Forestry, Inst Wetland Res, Beijing, Peoples R China.; Kang, XM (通讯作者)，Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China.; Kang, XM (通讯作者)，Tibetan Autonomous Prefecture Aba, Sichuan Zoige Wetland Ecosyst Res Stn, Ngawa, Sichuan, Peoples R China. EM xmkang@ucas.ac.cn TC 5 Z9 5 PD FEB 2 PY 2022 VL 13 AR 824267 DI 10.3389/fmicb.2022.824267 UT WOS:000759469500001 DA 2023-03-23 ER PT J AU Liu, L Zhuang, QL Zhao, DS Zheng, D Kou, D Yang, YH AF Liu, Lei Zhuang, Qianlai Zhao, Dongsheng Zheng, Du Kou, Dan Yang, Yuanhe TI Permafrost Degradation Diminishes Terrestrial Ecosystem Carbon Sequestration Capacity on the Qinghai-Tibetan Plateau SO GLOBAL BIOGEOCHEMICAL CYCLES DT Article AB Effects of permafrost degradation on carbon (C) and nitrogen (N) cycling on the Qinghai-Tibetan Plateau (QTP) have rarely been analyzed. This study used a revised process-based biogeochemical model to quantify the effects in the region during the 21st century. We found that permafrost degradation would expose 0.61 +/- 0.26 (mean +/- SD) and 1.50 +/- 0.15 Pg C of soil organic carbon under the representative concentration pathway (RCP) 4.5 and the RCP 8.5, respectively. Among them, more than 20% will be decomposed, enhancing heterotrophic respiration by 8.62 +/- 4.51 (RCP 4.5) and 33.66 +/- 14.03 (RCP 8.5) Tg C/yr in 2099. Deep soil N supply due to thawed permafrost is not accessible to plants, only stimulating net primary production by 7.15 +/- 4.83 (RCP 4.5) and 24.27 +/- 9.19 (RCP 8.5) Tg C/yr in 2099. As a result, the single effect of permafrost degradation would cumulatively weaken the regional C sink by 209.44 +/- 137.49 (RCP 4.5) and 371.06 +/- 151.70 (RCP 8.5) Tg C during 2020-2099. However, when factors of climate change, CO2 increasing and permafrost degradation are all considered, the permafrost region on the QTP would be a stronger C sink in the 21st century. Permafrost degradation has a greater influence on C balance of alpine meadows than alpine steppes on the QTP. The shallower active layer, higher soil C and N stocks, and wetter environment in alpine meadows are responsible for its stronger response to permafrost degradation. This study highlights that permafrost degradation could continue to release large amounts of C to the atmosphere irrespective of potentially more nitrogen available from deep soils. C1 [Liu, Lei; Zhao, Dongsheng; Zheng, Du] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing, Peoples R China. [Liu, Lei; Zheng, Du; Yang, Yuanhe] Univ Chinese Acad Sci, Beijing, Peoples R China. [Liu, Lei; Zhuang, Qianlai; Kou, Dan] Purdue Univ, Dept Earth Atmospher & Planetary Sci, W Lafayette, IN 47907 USA. [Kou, Dan] Univ Eastern Finland, Dept Environm & Biol Sci, Biogeochem Res Grp, Kuopio, Finland. [Yang, Yuanhe] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. RP Zhao, DS (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing, Peoples R China. EM zhaods@igsnrr.ac.cn TC 3 Z9 3 PD FEB PY 2022 VL 36 IS 2 AR e2021GB007068 DI 10.1029/2021GB007068 UT WOS:000765649200007 DA 2023-03-23 ER PT J AU Liu, QH Wang, XH Zhang, YL Li, SC AF Liu, Qionghuan Wang, Xiuhong Zhang, Yili Li, Shicheng TI Complex Ecosystem Impact of Rapid Expansion of Industrial and Mining Land on the Tibetan Plateau SO REMOTE SENSING DT Article AB The ecological security of the Tibetan Plateau is vital for sustainable development. In recent years, biodiversity loss and ecosystem degradation caused by industrial and mining activities have attracted wide attention. However, a synthesis assessment of the impacts of industrial and mining land (IML) on the ecosystem is currently lacking. In this study, based on the land cover data and normalized differential vegetation index, we used the landscape ecological index, Theil-Sen trend analysis and equivalent value factors method to evaluate the change in IML and its ecosystem impact on the TP. The results demonstrated that the area of IML expanded by 3.3 times (228.56%) during 1990-2020, and reached 968.95 km(2) in 2020. Within this area, the newly added, stable, and reduced areas were 842.71, 126.26, and 168.65 km(2), respectively. Simultaneously, IML expansion made the landscape more fragmented during 1990-2020. The number of patches, splitting index, and landscape shape index in 2020 increased by 3.59-, 2.70-, and 1.90-fold compared to those in 1990, respectively. Furthermore, the difference in the vegetation change between the IML and its 10 km buffer zone was significant. About 77.34% of the vegetation in the IML area showed a trend of decrease, while about 76.51% of the vegetation in the buffer zone of IML showed a trend of increase. In addition, the expansion of IML also reduced the total ecological services value by USD 6969.31 million (0.66%) from 1990 to 2020. However, the lowered value was USD 8649.50 million (0.82%) in the newly added IML. This study highlights the rapid expansion of IML and reveals the ecosystem structure, ecosystem quality, and ecosystem service impact on the TP, which helps guide ecosystem protection and the sustainable development of mining. C1 [Liu, Qionghuan] Shenzhen Univ, Res Inst Smart Cities, Sch Architecture & Urban Planning, Shenzhen 518060, Peoples R China. [Liu, Qionghuan; Wang, Xiuhong; Zhang, Yili] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Zhang, Yili] State Key Lab Tibetan Plateau Earth Syst Resource, Beijing 100101, Peoples R China. [Zhang, Yili] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Li, Shicheng] China Univ Geosci, Sch Publ Adm, Dept Land Resource Management, Wuhan 430074, Peoples R China. RP Zhang, YL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China.; Zhang, YL (通讯作者)，State Key Lab Tibetan Plateau Earth Syst Resource, Beijing 100101, Peoples R China.; Zhang, YL (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM liuqh.16b@igsnrr.ac.cn; wangxh@igsnrr.ac.cn; zhangyl@igsnrr.ac.cn; lisc@cug.edu.cn TC 1 Z9 1 PD FEB PY 2022 VL 14 IS 4 AR 872 DI 10.3390/rs14040872 UT WOS:000765117900001 DA 2023-03-23 ER PT J AU Wang, F Kong, WD Ji, MK Zhao, K Chen, H Yue, LY Dong, XB AF Wang, Fei Kong, Weidong Ji, Mukan Zhao, Kang Chen, Hao Yue, Linyan Dong, Xiaobin TI Grazing greatly reduces the temporal stability of soil cellulolytic fungal community in a steppe on the Tibetan Plateau SO JOURNAL OF ENVIRONMENTAL SCIENCES DT Article AB Excessive livestock grazing degrades grasslands ecosystem stability and sustainability by reducing soil organic matter and plant productivity. However, the effects of grazing on soil cellulolytic fungi, an important indicator of the degradation process for soil organic matter, remain less well understood. Using T-RFLP and sequencing methods, we investigated the effects of grazing on the temporal changes of cellulolytic fungal abundance and community structure in dry steppe soils during the growing months from May to September, on the Tibetan Plateau using T-RFLP and sequencing methods. The results demonstrated that the abundance of soil cellulolytic fungi under grazing treatment changed significantly from month to month, and was positively correlated with dissolved organic carbon (DOC) and soil temperature, but negatively correlated with soil pH. Contrastingly, cellulolytic fungal abundance did not change within the fencing treatment (ungrazed conditions). Cellulolytic fungal community structure changed significantly in the growing months in grazed soils, but did not change in fenced soils. Grazing played a key role in determining the community structure of soil cellulolytic fungi by explaining 8.1% of the variation, while pH and DOC explained 4.1% and 4.0%, respectively. Phylogenetically, the cellulolytic fungi were primarily affiliated with Ascomycota (69.65% in relative abundance) and Basidiomycota (30.35%). Therefore, grazing substantially reduced the stability of soil cellulolytic fungal abundance and community structure, as compared with the fencing treatment. Our finding provides a new insight into the responses of organic matter-decomposing microbes for grassland managements. (C) 2022 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. C1 [Wang, Fei; Kong, Weidong; Ji, Mukan; Zhao, Kang; Chen, Hao; Yue, Linyan] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Wang, Fei; Kong, Weidong; Ji, Mukan; Chen, Hao; Yue, Linyan] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100039, Peoples R China. [Kong, Weidong] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhao, Kang] Shanxi Normal Univ, Sch Life Sci, Linfen 041004, Shanxi, Peoples R China. [Dong, Xiaobin] Beijing Normal Univ, Coll Resources Sci & Technol, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. RP Kong, WD (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China.; Kong, WD (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100039, Peoples R China.; Kong, WD (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. EM wdkong@itpcas.ac.cn TC 2 Z9 2 PD NOV PY 2022 VL 121 BP 48 EP 57 DI 10.1016/j.jes.2021.09.023 EA FEB 2022 UT WOS:000800545000006 DA 2023-03-23 ER PT J AU Wang, SJ Wei, YQ AF Wang, Shijin Wei, Yanqiang TI Qinghai-Tibetan Plateau Greening and Human Well-Being Improving: The Role of Ecological Policies SO SUSTAINABILITY DT Article AB Appropriate human activities can have significantly positive effects on vegetation dynamics. In the past 50 years, various ecological policies have improved both ecological change and human well-being in the Qinghai-Tibetan Plateau (QTP), efficiently achieving multiple Sustainable Development Goals (SDGs) of the United Nations' 2030 Agenda for Sustainable Development. During 1981-2017, the annual mean normalized difference vegetation index (NDVI) of the protected areas (PAs) tended to increase significantly at a rate of 2.93 x 10(-4)/a (p < 0.01), while non-PAs only increased by 0.6 x 10(-4)/a (p < 0.5). Improvement in the NDVI of the PAs is more obvious than that of non-PAs. Specifically, the earlier the establishment of the Pas is, the more significant the greening effect will be. Moreover, ecological protection has not slowed improvements in human welfare; on the contrary, the Human Development Index (HDI) has nearly doubled in the past 40 years. In terms of global ecological construction, the Chinese government has demonstrated the responsibilities of a large country in global ecological governance. Chinese initiatives can guide other nations in contributing to the global sustainability aspirations embodied in the 2030 SDGs Agenda. This study can be used as a reference for other countries in the world to coordinate the development of ecological protection and well-being. C1 [Wang, Shijin] Chinese Acad Sci, Yulong Snow Mt Cryosphere & Sustainable Dev Obser, State Key Lab Cryospher Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. [Wei, Yanqiang] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou 730000, Peoples R China. RP Wang, SJ (通讯作者)，Chinese Acad Sci, Yulong Snow Mt Cryosphere & Sustainable Dev Obser, State Key Lab Cryospher Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China.; Wei, YQ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Lanzhou 730000, Peoples R China. EM wangshijin@lzb.ac.cn; weiyq@lzb.ac.cn TC 2 Z9 2 PD FEB PY 2022 VL 14 IS 3 AR 1652 DI 10.3390/su14031652 UT WOS:000755281800001 DA 2023-03-23 ER PT J AU Qian, DW Li, Q Fan, B Guo, XW Du, YG Cao, GM AF Qian, Dawen Li, Qian Fan, Bo Guo, Xiaowei Du, Yangong Cao, Guangmin TI Landscape pattern changes across alpine shrub meadows gradient in warm-season pastures on the Qinghai-Tibet Plateau SO ECOLOGICAL COMPLEXITY DT Article AB Grassland degradation has been one of the major ecological concerns on the Qinghai-Tibet Plateau (QTP) in recent years, but the degradation of alpine shrub meadows, and in particular the changes in its surface landscape pattern, has been less well assessed. This study selected a warm-season pasture on the QTP as a study area, and used an unmanned aerial vehicle (UAV) to collect aerial photographs along the degradation gradient from late June to early July 2018. We then classified the surface landscape as alpine shrub, alpine meadow, bare soil and plateau pika hole and analyzed the landscape pattern changes at different degradation levels. The results showed that the alpine shrub and alpine meadow dominated landscape degraded to a pattern of alpine meadow and bare soil dominance and pika hole pervasiveness, during which vegetation cover declined and the overall landscape pattern tended to fragment. Landscape pattern characteristics related to the area, density, connectivity and boundaries respond more clearly to the shrub degradation, with moderate degradation being the key stage at which the surface landscape pattern changes dramatically. Our study demonstrates a potential application of UAV technology in the study of grassland degradation. Future research should focus on the status, mechanisms and ecological effects of alpine shrub meadows degradation and the quantitative relationships between surface landscape patterns and ecological functions. C1 [Qian, Dawen; Li, Qian; Fan, Bo; Guo, Xiaowei; Du, Yangong; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, Xining, Qinghai, Peoples R China. [Qian, Dawen; Li, Qian; Fan, Bo; Guo, Xiaowei; Du, Yangong; Cao, Guangmin] 23 Xinning Rd, Xining 810008, Qinghai, Peoples R China. RP Qian, DW (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, Xining, Qinghai, Peoples R China.; Qian, DW (通讯作者)，23 Xinning Rd, Xining 810008, Qinghai, Peoples R China. EM dwqian@nwipb.cas.cn; liqian@nwipb.cas.cn; fanbo@nwipb.cas.cn; guoxw@nwipb.cas.cn; ygdu@nwipb.cas.cn; caogm@nwipb.cas.cn TC 0 Z9 0 PD MAR PY 2022 VL 49 AR 100979 DI 10.1016/j.ecocom.2022.100979 EA JAN 2022 UT WOS:000777817500002 DA 2023-03-23 ER PT J AU Zhang, YR Li, YQ Liu, LN Wang, NN Cao, XY AF Zhang, Yanrong Li, Yunqing Liu, Lina Wang, Nannan Cao, Xianyong TI No evidence of human disturbance to vegetation in the Zoige Region (north-eastern Tibetan Plateau) in the last millennium until recent decades SO PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY DT Article AB A high-resolution record (-5-20 years per sample) of pollen, charcoal, total organic carbon (TOC), and total nitrogen (TN) was analysed from a core obtained from a small lake (Xing Co) on the northeastern Tibetan Plateau. Findings shed light on vegetation change and its driving forces over the last-1440 years and the impact of recent human activities. Between ca. 580 and 1300 CE, vegetation was alpine meadow, dominated by Cyperaceae with low percentages of Poaceae and Artemisia. Pollen spectra indicate that vegetation shifted to dry alpine steppe dominated by Poaceae and Artemisia between 1300 and 1470 CE, possibly as a response to reduced precipitation and cooler temperatures linked to the transition from the Medieval Warm Period (MWP) to the Little Ice Age (LIA). A further significant increase of Poaceae from 1770 to 1910 CE indicates consolidation of the alpine steppe. However, after 1910 CE, pollen spectra are characterized by decreasing Poaceae abundance and increasing abundances of Artemisia, Cyperaceae, Ranunculaceae, Thalictrum, and Polygonaceae, with high pollen richness and evenness. These recent vegetation changes are probably caused, at least in part, by enhanced human impacts. Furthermore, our analysis also shows an significant increase in percentages of Pediastrum and Potamogeton together with a sharp increase in TN after ca. 1990 CE, suggesting eutrophication of the lake water. Therefore, our record suggests that human activities did not have any significant impact on the composition of the vegetation until recent decades at Xing Co. C1 [Zhang, Yanrong; Liu, Lina; Wang, Nannan; Cao, Xianyong] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Grp Alpine Paleoecol & Human Adaptat ALPHA, Beijing 100101, Peoples R China. [Zhang, Yanrong; Liu, Lina; Wang, Nannan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Li, Yunqing] Capital Normal Univ, Coll Resource Environm & Tourism, Beijing, Peoples R China. RP Cao, XY (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Grp Alpine Paleoecol & Human Adaptat ALPHA, Beijing 100101, Peoples R China. EM xcao@itpcas.ac.cn TC 2 Z9 2 PD MAR 1 PY 2022 VL 589 AR 110843 DI 10.1016/j.palaeo.2022.110843 EA JAN 2022 UT WOS:000789221000003 DA 2023-03-23 ER PT J AU Li, M Hao, YB Yan, ZQ Kang, EZ Wang, JZ Zhang, KR Li, Y Wu, HD Kang, XM AF Li, Meng Hao, Yanbin Yan, Zhongqing Kang, Enze Wang, Jinzhi Zhang, Kerou Li, Yong Wu, Haidong Kang, Xiaoming TI Long-term degradation from marshes into meadows shifts microbial functional diversity of soil phosphorus cycling in an alpine wetland of the Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Soil microbes greatly contribute to the regulating of phosphorus (P) cycling, which plays a significant role in maintaining wetland ecosystem processes and function. The microbial functional diversity of soil P cycling in response to wetland degradation, however, remains largely unknown. We used metagenomic sequencing to investigate the microbial community and genes related to soil P cycling in un-degraded marshes and meadows derived from long-term marsh degradation in the Lalu alpine wetland of the Tibetan Plateau. When the marsh degraded into meadow, organic P (OP) mineralization genes increased while genes related to P-starvation response regulation decreased. Proteobacteria (20.5-74.3%) and Actinobacteria (5.6-59.7%) were the dominant phyla in soils and were also the main contributors (39.7-84.1% in total) to soil P-cycling genes. Soil pH was the primary factor influencing the P-cycling functional genes. Soil pH negatively affected the genes related to the P-uptake and transport system and had negative effects on the genes related to P-starvation response regulation, OP mineralization, and inorganic P solubilization. These findings may deepen our understanding of the biogeochemical process of soil OP and may be beneficial for wetland management. C1 [Li, Meng; Yan, Zhongqing; Kang, Enze; Wang, Jinzhi; Zhang, Kerou; Li, Yong; Wu, Haidong; Kang, Xiaoming] Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China. [Li, Meng; Yan, Zhongqing; Kang, Enze; Wang, Jinzhi; Zhang, Kerou; Li, Yong; Wu, Haidong; Kang, Xiaoming] Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China. [Li, Meng; Yan, Zhongqing; Kang, Enze; Wang, Jinzhi; Zhang, Kerou; Li, Yong; Wu, Haidong; Kang, Xiaoming] Sichuan Zoige Wetland Ecosyst Res Stn, Tibetan Autonomous Prefe, Peoples R China. [Hao, Yanbin] Univ Chinese Acad Sci, Coll Life Sci, Beijing, Peoples R China. [Wu, Haidong] Minist Ecol & Environm, Informat Ctr, Beijing, Peoples R China. RP Kang, XM (通讯作者)，Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China. EM xmkang@ucas.ac.cn TC 3 Z9 3 PD FEB 28 PY 2022 VL 33 IS 4 BP 628 EP 637 DI 10.1002/ldr.4180 EA JAN 2022 UT WOS:000742076100001 DA 2023-03-23 ER PT J AU Wang, JL Li, W Cao, WX Wang, SL AF Wang, Jinlan Li, Wen Cao, Wenxia Wang, Shilin TI Effects of different intensities of long-term grazing on plant diversity, biomass and carbon stock in alpine shrubland on the Qinghai-Tibetan Plateau SO PEERJ DT Article AB Grazing is the main grassland management strategy applied in alpine shrubland ecosystems on the Qinghai-Tibetan Plateau. However, how different intensities of long-term grazing affect plant diversity, biomass accumulation and carbon (C) stock in these ecosystems is poorly understood. In this study, alpine shrubland with different longterm (more than 30 years) grazing intensities (excluded from grazing for 5 years (EX), light grazing (LG), moderate grazing (MG) and heavy grazing (HG)) on the Qinghai-Tibetan Plateau were selected to study changes in plant diversity, aboveground biomass and C accumulation, as well as distribution of C stock among biomass components and soil depths. A structural equation model was used to illustrate the impact of grazing on the soil carbon stock (SOC). The results showed that the Shannon-Wiener diversity index and richness index of herbaceous plants, shrubs, and communities first significantly increased and then decreased with increasing grazing intensity, reaching maxima at the LG site. The aboveground and belowground and litter biomass of understory herbaceous plants, shrubs and communities decreased with increasing grazing intensity, reaching maxima at the EX site. The aboveground and belowground biomass C storage decreased with increasing grazing intensity, reaching maxima at the EX site. The SOC stock and total ecosystem C stock decreased with increasing grazing intensity, reaching maxima at the EX and LG sites. A structural equation model showed that grazing-induced changes in the belowground biomass of understory herbaceous plants greatly contributed to the SOC stock decrease. Thus, considering the utilization and renewal of grassland resources, as well as local economic benefits and ecological effects, LG may be a more rational grazing intensity for species diversity conservation and ecosystem C sequestration in alpine shrubland. Our results provide new insights for incorporating grazing intensity into shrub ecosystem C stock and optimizing grazing management and grassland ecosystem C management. C1 [Wang, Jinlan; Cao, Wenxia; Wang, Shilin] Gansu Agr Univ, Grassland Sci Coll, Lanzhou, Gansu, Peoples R China. [Li, Wen] Qinghai Univ, Qinghai Acad Anim Sci & Vet Med, Xining, Qinghai, Peoples R China. RP Cao, WX (通讯作者)，Gansu Agr Univ, Grassland Sci Coll, Lanzhou, Gansu, Peoples R China. EM caowx@gsau.edu.cn TC 3 Z9 3 PD JAN 12 PY 2022 VL 10 AR e12771 DI 10.7717/peerj.12771 UT WOS:000759251800004 DA 2023-03-23 ER PT J AU Zhang, LN Zhang, HQ Xu, EQ AF Zhang, Lina Zhang, Hongqi Xu, Erqi TI Information entropy and elasticity analysis of the land use structure change influencing eco-environmental quality in Qinghai-Tibet Plateau from 1990 to 2015 SO ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH DT Review AB Regional land use change affects eco-environmental quality by altering ecosystem structure and function. The primitive ecosystem and environment of the Qinghai-Tibet Plateau (QTP) occupies a special position in the world, but it is very fragile. Although land use activities on the plateau have increased gradually in past decades, its effects on eco-environmental quality and the underlying mechanisms of regional heterogeneity remain unclear. In this study, an eco-environmental quality assessment index system was established to characterize the QTP, and the information entropy and elasticity methods were introduced to quantify the impact of land use dynamic trajectory on the eco-environmental quality. It provides a statistical measurement of system structure and more information than the traditional methods to reveal the land use change. The area change in land use on QTP was small from 1990 to 2015. The unused land and forest decreased, but those of grassland, water body, built-up land, and cultivated land increased. The overall eco-environmental quality on the QTP was low, and increased at a rate of 9.39% over the past 25 years, presenting a distribution of decreasing from southeast to northwest. The improvement in eco-environmental quality attributed to land use change was mainly due to the conversion of unused land into grassland, and ecological conservation projects also improved the local ecological environment. Conversely, the expansion of built-up land and land degradation contributed to decline in local eco-environmental quality in the Hengduan Mountains, northeastern plateau, and Qaidam Basin. The results indicated that under the influence of climate change, the changes in land use and eco-environmental quality were inconsistent in part regions, mainly including the central and southern Tibet and the border zone. Regions in which eco-environmental quality has been degraded by unreasonable land use are urgent to optimize land use management. C1 [Zhang, Lina; Zhang, Hongqi; Xu, Erqi] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Zhang, Lina] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Xu, EQ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM zhanghq@igsnrr.ac.cn; xueq@igsnrr.ac.cn TC 8 Z9 8 PD MAR PY 2022 VL 29 IS 13 BP 18348 EP 18364 DI 10.1007/s11356-021-17978-2 EA JAN 2022 UT WOS:000741964500015 DA 2023-03-23 ER PT J AU Qian, DW Du, YG Li, Q Guo, XW Fan, B Cao, GM AF Qian, Dawen Du, Yangong Li, Qian Guo, Xiaowei Fan, Bo Cao, Guangmin TI Impacts of alpine shrub-meadow degradation on its ecosystem services and spatial patterns in Qinghai-Tibetan Plateau SO ECOLOGICAL INDICATORS DT Article AB Alpine shrub-meadow is an important ecosystem type on the Qinghai-Tibetan Plateau, providing a variety of ecosystem services while supporting the livelihoods of pastoralists. However, there is a clear lack of understanding of the changes in spatial patterns and ecosystem services of alpine shrub-meadow degradation. This study combined aerial photography and ground surveys to investigate and analyse the impact of degradation on the spatial patterns of alpine shrub-meadow and their ecosystem services, and the relationships between the spatial patterns and ecosystem services. The results showed that degradation led to fragmentation and patchiness in alpine shrub-meadow, as evidenced by a decrease in the proportion of shrub and meadow area and average patch size, as well as the complexity of patch boundaries and shapes. Light and moderate degradation reduced all ecosystem services in alpine shrub-meadow, with carbon storage, nutrient supply and water retention services decreased by an average of 27.4%, 17.3% and 13.8% respectively, while forage supply services decreased by 65.2% at heavy degradation, and the reduction in alpine meadow ecosystem services was even greater. Regulating services increased again at heavy degradation due to the accumulation and slow decomposition of plant underground roots, and rodent activity. The spatial patterns of the meadow layer were more closely related to its ecosystem services than the shrub layer, and fragmentation and patchiness were positively related to ecosystem services. Our findings suggest that the impact of degradation on alpine shrub-meadow ecosystem services may be non-linear and that the relationships between spatial patterns and ecosystem services need to be interpreted with caution and should be analysed comprehensively with a wider range of influencing factors. Our results have implications for grassland restoration and ecosystem service management on the Qinghai-Tibetan Plateau. C1 [Qian, Dawen; Du, Yangong; Li, Qian; Guo, Xiaowei; Fan, Bo; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, 23 Xining Rd, Xining 810008, Qinghai, Peoples R China. RP Qian, DW (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, 23 Xining Rd, Xining 810008, Qinghai, Peoples R China. EM dwqian@nwipb.cas.cn TC 6 Z9 6 PD FEB PY 2022 VL 135 AR 108541 DI 10.1016/j.ecolind.2022.108541 EA JAN 2022 UT WOS:000761396700003 DA 2023-03-23 ER PT J AU Xu, YD Dong, SK Gao, XX Wu, SN Yang, MY Li, S Shen, H Xiao, JN Zhi, YL Zhao, XY Mu, ZY Liu, SL AF Xu, Yudan Dong, Shikui Gao, Xiaoxia Wu, Shengnan Yang, Mingyue Li, Shuai Shen, Hao Xiao, Jiannan Zhi, Yangliu Zhao, Xinyue Mu, Zhiyuan Liu, Shiliang TI Target species rather than plant community tell the success of ecological restoration for degraded alpine meadows SO ECOLOGICAL INDICATORS DT Article AB Ecological conservation and restoration projects in Three-river Headwater Region (TRHR) have been implemented to respond to the serious degradation of alpine meadow ecosystem. Compared with the substantial amount of studies on the recovery of plant communities, soil quality and ecosystem services, few studies have focused on the restoration performance of target species. Therefore, we conducted this study to analyze the dynamics and underlying mechanisms of species richness and aboveground biomass of plant communities and target species. The results showed that restoration actions (grassland cultivation and fencing) did not significantly improve the community aboveground biomass of the degraded alpine meadows, while the actions did significantly promote community species richness, target species richness and target species aboveground biomass. Community species richness (20%-45%) was significantly impacted by the restoration strategies, and community aboveground biomass (31%-53%) was impacted by the mean annual precipitation and mean annual temperature. The species richness (57%) and aboveground biomass (63%) of the target species were directly and indirectly impacted by restoration actions, climatic factors, biotic factors and soil factors. The implications of this study stress that target species should be highlighted in assessing the restoration success of degraded alpine meadows. Integrating climatic factors, target species and other biotic and abiotic indicators could help us better understand and evaluate restoration actions for degraded alpine meadows in the TRHR or other similar regions worldwide. C1 [Xu, Yudan] Shanxi Agr Univ, Coll Grassland Sci, Jinzhong 030801, Peoples R China. [Dong, Shikui; Wu, Shengnan; Shen, Hao] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. [Dong, Shikui; Yang, Mingyue; Xiao, Jiannan; Zhi, Yangliu; Zhao, Xinyue; Mu, Zhiyuan; Liu, Shiliang] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Gao, Xiaoxia] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Li, Shuai] Shanxi Agr Univ, Coll Resources & Environm, Jinzhong 030801, Peoples R China. RP Dong, SK (通讯作者)，Shanxi Agr Univ, Coll Grassland Sci, Jinzhong 030801, Peoples R China. EM dongshikui@sina.com TC 2 Z9 2 PD FEB PY 2022 VL 135 AR 108487 DI 10.1016/j.ecolind.2021.108487 EA JAN 2022 UT WOS:000761373600001 DA 2023-03-23 ER PT J AU Yu, JL Wan, LF Liu, GH Ma, KM Cheng, H Shen, Y Liu, YQ Su, XK AF Yu, Jiale Wan, Lingfan Liu, Guohua Ma, Keming Cheng, Hao Shen, Yu Liu, Yuqing Su, Xukun TI A Meta-Analysis on Degraded Alpine Grassland Mediated by Climate Factors: Enlightenment for Ecological Restoration SO FRONTIERS IN PLANT SCIENCE DT Article AB Alpine grassland is the main ecosystem on the Qinghai-Tibet Plateau (QTP). Degradation and restoration of alpine grassland are related to ecosystem function and production, livelihood, and wellbeing of local people. Although a large number of studies research degraded alpine grassland, there are debates about degradation patterns of alpine grassland in different areas and widely applicable ecological restoration schemes due to the huge area of the QTP. In this study, we used the meta-analysis method to synthesize 80 individual published studies which were conducted to examine aboveground and underground characteristics in non-degradation (ND), light degradation (LD), moderate degradation (MD), heavy degradation (HD), and extreme degradation (ED) of alpine grassland on the QTP. Results showed that aboveground biomass (AGB), belowground biomass (BGB), Shannon-Wiener index (H '), soil moisture (SM), soil organic carbon (SOC), soil total nitrogen (TN), and available nitrogen (AN) gradually decreased along the degradation gradient, whereas soil bulk density (BD) and soil pH gradually increased. In spite of a tendency to soil desertification, losses of other soil nutrients and reduction of enzymes, there was no linear relationship between the variations with degradation gradient. Moreover, the decreasing extent of TN was smaller in areas with higher precipitation and temperature, and the decreasing extent of AGB, SOC, and TN was larger in areas with a higher extent of corresponding variables in the stage of ND during alpine grassland degradation. These findings suggest that in areas with higher precipitation and temperature, reseeding and sward cleavage can be used for restoration on degraded alpine grassland. Fencing and fertilization can be used for alpine grassland restoration in areas with lower precipitation and temperature. Microbial enzymes should not be used to restore degraded alpine grassland on a large scale on the QTP without detailed investigation and analysis. Future studies should pay more attention to the effects of climate factors on degradation processes and specific ecological restoration strategies in different regions of the QTP. C1 [Yu, Jiale; Wan, Lingfan; Liu, Guohua; Ma, Keming; Cheng, Hao; Shen, Yu; Liu, Yuqing; Su, Xukun] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing, Peoples R China. [Yu, Jiale; Wan, Lingfan; Liu, Guohua; Ma, Keming; Cheng, Hao; Shen, Yu; Liu, Yuqing; Su, Xukun] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. RP Ma, KM; Su, XK (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing, Peoples R China.; Ma, KM; Su, XK (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. EM mkm@rcees.ac.cn; xksu@rcees.ac.cn TC 4 Z9 4 PD JAN 7 PY 2022 VL 12 AR 821954 DI 10.3389/fpls.2021.821954 UT WOS:000749825500001 DA 2023-03-23 ER PT J AU Lin, HL Zhao, YT AF Lin, Huilong Zhao, Yuting TI Soil Erosion Assessment of Alpine Grassland in the Source Park of the Yellow River on the Qinghai-Tibetan Plateau, China SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB The source park of the Yellow River (SPYR), as a vital ecological shelter on the Qinghai-Tibetan Plateau, is suffering different degrees of degradation and desertification, resulting in soil erosion in recent decades. Therefore, studying the mechanism, influencing factors and current situation of soil erosion in the alpine grassland ecosystems of the SPYR are significant for protecting the ecological and productive functions. Based on the Cs-137 element tracing technique and machine learning algorithms, five strategic variable selection algorithms based on machine learning algorithms are used to identify the minimal optimal set and analyze the main factors that influence soil erosion in the SPYR. The optimal model for estimating soil erosion in the SPYR is obtained by comparisons model outputs between the RUSLE and machine learning algorithms combined with variable selection models. We identify the spatial distribution pattern of soil erosion in the study area by the optimal model. The results indicated that: (1) A comprehensive set of variables is more objective than the RUSLE model. In terms of verification accuracy, the simulated annealing -Cubist model (R = 0.67, RMSD = 1,368 t km(-2) . a(-1)) simulation results represents the best while the RUSLE model (R = 0.49, RMSD = 1,769 t . km(-2) . a(-1)) goes on the worst. (2) The soil erosion is more severe in the north than the southeast of the SPYR. The average erosion modulus is 6,460.95 t . km(-2) . a(-1) and roughly 99% of the survey region has an intensive erosion modulus (5,000-8,000 t . km(-2) . a(-1)). (3) Total erosion loss is relatively 8.45 . 108 t . a(-1) in the SPYR, which is commonly 12.64 times greater than the allowable soil erosion loss. The economic monetization of SOC loss caused by soil erosion in the entire research area was almost $47.90 billion in 2014. These results will help provide scientific evidences not only for farmers and herdsmen but also for environmental science managers and administrators. In addition, a new ecological policy recommendation was proposed to balance grassland protection and animal husbandry economic production based on the value of soil erosion reclassification. C1 [Lin, Huilong; Zhao, Yuting] Lanzhou Univ, State Key Lab Grassland AgroEcosyst, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs,Coll Pastoral Agr Sci, Lanzhou, Peoples R China. RP Lin, HL (通讯作者)，Lanzhou Univ, State Key Lab Grassland AgroEcosyst, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs,Coll Pastoral Agr Sci, Lanzhou, Peoples R China. EM linhuilong@lzu.edu.cn TC 1 Z9 1 PD JAN 5 PY 2022 VL 9 AR 771439 DI 10.3389/fevo.2021.771439 UT WOS:000745174100001 DA 2023-03-23 ER PT J AU Zhang, L Wang, XT Wang, J Liao, LR Lei, SL Liu, GB Zhang, C AF Zhang, Lu Wang, Xiangtao Wang, Jie Liao, Lirong Lei, Shilong Liu, Guobin Zhang, Chao TI Alpine meadow degradation depresses soil nitrogen fixation by regulating plant functional groups and diazotrophic community composition SO PLANT AND SOIL DT Article AB Aims Biological nitrogen fixation (BNF), a function performed by diazotrophic microbes, plays an essential role in nitrogen (N) bioavailability in terrestrial ecosystems. However, little is known about the effects of meadow degradation on soil BNF and diazotrophic communities in alpine meadows. Methods We investigated changes in soil BNF and their potential drivers in alpine meadows along a degradation gradient on the Tibetan Plateau (non-degraded, lightly degraded, moderately degraded, and severely degraded meadows) using real-time quantitative PCR and amplicon sequencing. Results Soil BNF rates decreased significantly along the meadow degradation gradient with a range of 17.34-79.84 nmol C2H4 g(-1) dry soil d(-1) across all sites. The highest BNF rate in the non-degraded meadow was 1.5-4.6-fold higher than that in the degraded meadows. The abundance and diversity of diazotrophs measured by nifH abundance and Shannon diversity was also decreased in the degraded meadows, accompanied by decreases in plant biomass, soil moisture, and nutrient content (C, N). Soil BNF rate was correlated with plant biomass, soil nutrient content, and diazotrophic abundance (including Nostoc, Scytonema, Rhodopseudomonas, and unidentified genera within the Rhizobiales and Proteobacteria). The community composition of diazotrophs differed markedly among sites with different levels of degradation, with both autotrophic (Cyanobacteria) and heterotrophic (Proteobacteria) diazotrophs contributing significantly to BNF. The plant functional groups, particularly the sedge family, were the primary drivers of soil BNF rates via mediating soil moisture, nutrient content (dissolved organic C and N), nifH gene abundance, and diazotrophic community composition. Conclusions Our results reveal the main drivers of decreased BNF during alpine meadow degradation and emphasize the importance of plant functional groups in shaping the diazotrophic community and regulating the BNF rate. This information can be applied to the restoration of degraded meadow ecosystems. C1 [Zhang, Lu; Liao, Lirong; Liu, Guobin; Zhang, Chao] Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Zhang, Lu; Liao, Lirong] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Xiangtao] Xizang Agr & Anim Husb Coll, Dept Anim Sci, Linzhi 860000, Peoples R China. [Wang, Jie; Lei, Shilong; Liu, Guobin; Zhang, Chao] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. RP Zhang, C (通讯作者)，Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. EM zhangchaolynn@163.com TC 5 Z9 5 PD APR PY 2022 VL 473 IS 1-2 SI SI BP 319 EP 335 DI 10.1007/s11104-021-05287-z EA JAN 2022 UT WOS:000737724000001 DA 2023-03-23 ER PT J AU Zou, X Hou, SG Wu, SY Pang, HX Liu, K Zhang, WB Yu, JH Song, J Huang, RH Liu, YP AF Zou, Xiang Hou, Shugui Wu, Shuangye Pang, Hongxi Liu, Ke Zhang, Wangbin Yu, Jinhai Song, Jing Huang, Renhui Liu, Yaping TI Ice-core based assessment of nitrogen deposition in the central Tibetan Plateau over the last millennium SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Atmospheric nitrogen deposition is a unique source of bioavailable nitrogen for ecosystems in remote regions, and has vital impacts on ecological processes. Understanding variations of atmospheric nitrogen deposition in these regions remains challenging due to a lack of observations. Ice cores contain records of nitrogen species of nitrate (NO3-) and ammonium(NH4+), hence provide valuable long-termdata to study past variations of atmospheric nitrogen deposition. In this study, we present an annually resolved record of NH4+ and NO3- over the past millennium, derived from the Zangser Kangri (ZK) ice core in the central Tibetan Plateau. The concentration peaks of NH4+ and NO3- coincide with those of Ca2+ (a dust tracer), indicating that variation of nitrogen species in the ZK ice core is largely driven by dust activities. An EOF analysis for all chemical species (Cl-, SO42-, NO3-, Na+, NH4+, K+, Mg2+, Ca2+) reveals significant but separate loadings of NH4+ and NO3- on EOF 2, suggesting an additional source of nitrogen, likely from biogenic emissions of terrestrial ecosystems. Over the past millennium, the EOF 2 series has relatively high values around 1300 CE and 1600 CE, and has increased significantly since the Industrial Revolution. These variations are likely driven by temperature-dependent biogenic emissions on the Tibetan Plateau. Analyses of seasonal air mass backward trajectories and wind fields find that the chemical concentrations in the ZK ice core are mostly influenced by the westerly, but South Asia summer monsoon plays an important role in the transport of nitrogen species generated from biogenic emissions. This is further confirmed by the significant correlation between EOF 2 series and the South Asian summer monsoon index. This study provides new insight into the preindustrial sources, natural variabilities and major drivers of nitrogen deposition on the Tibetan Plateau. C1 [Zou, Xiang; Hou, Shugui; Pang, Hongxi; Liu, Ke; Zhang, Wangbin; Yu, Jinhai; Song, Jing; Huang, Renhui] Nanjing Univ, Sch Geog & Ocean Sci, Nanjing 210023, Peoples R China. [Hou, Shugui] Shanghai Jiao Tong Univ, Sch Oceanog, Shanghai 200240, Peoples R China. [Wu, Shuangye] Univ Dayton, Dept Geol & Environm Geosci, Dayton, OH 45469 USA. [Liu, Yaping] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Lanzhou, Peoples R China. RP Hou, SG (通讯作者)，Nanjing Univ, Sch Geog & Ocean Sci, Nanjing 210023, Peoples R China. EM shugui@nju.edu.cn TC 3 Z9 3 PD MAR 25 PY 2022 VL 814 AR 152692 DI 10.1016/j.scitotenv.2021.152692 EA JAN 2022 UT WOS:000743212500006 DA 2023-03-23 ER PT J AU Wang, RJ Feng, QS Jin, ZR Liang, TA AF Wang, Ruijing Feng, Qisheng Jin, Zheren Liang, Tiangang TI The Restoration Potential of the Grasslands on the Tibetan Plateau SO REMOTE SENSING DT Article AB While the alpine grassland ecosystems on the Tibetan Plateau (TP) have generally improved in recent years, some grasslands still suffer from varying degrees of degradation. Studying the restoration potential (R) of the grasslands on the TP is crucial to the conservation and restoration of its alpine grassland ecosystems. Few studies have assessed the restoration value of the alpine grasslands on the TP. We attempt to estimate the actual (ANPP) and potential net primary productivity (PNPP) of the grasslands on the TP. On this basis, we defined R as the "gap" between the current and highest achievable levels of restoration of a grassland. Then, R estimates were yielded for the alpine grasslands on the TP, which we used to analyze the restoration value of these grasslands. Specifically, based on the meteorological data for the period 2001-2019, in conjunction with remote-sensing imagery acquired by a moderate-resolution imaging spectroradiometer for the same period, the Carnegie-Ames-Stanford approach model was selected to produce ANPP estimates for the grasslands on the TP. Then, the Thornthwaite memorial model, the principle of similar habitats, and the Chikugo model, were employed to generate PNPP estimates for these grasslands. In addition, the R of these grasslands was then assessed based on the difference between their PNPP and ANPP. The main results are summarized as follows. (1) A multiyear mean R of 332.33 g C center dot m(-2) (81.59% of the ANPP) was determined for the grasslands on the TP over the period 2001-2019. A notable spatial distribution pattern of high Rs in the southwestern, eastern and middle parts of the TP, and low Rs in the northwestern part of the TP were also identified. Most of the grasslands in areas such as the southern part of Nagqu, the southwestern part of Ngari, Xigaze, Garze Tibetan Autonomous Prefecture, Aba Tibetan and Qiang Autonomous Prefecture, Gannan Tibetan Autonomous Prefecture, Huangnan Tibetan Autonomous Prefecture, Haibei Tibetan Autonomous Prefecture, Guoluo Tibetan Autonomous Prefecture and Yushu Tibetan Autonomous Prefecture were found to have high restoration value. (2) Grasslands with a stable R account were the highest proportion (76.13%) of all the grasslands on the TP, followed by those with a decreasing R (19.62%) and those with an increasing R (4.24%). Grasslands with an increasing R were mainly concentrated in the southern part of Xigaze, and parts of Yushu Tibetan Autonomous Prefecture, Guoluo Tibetan Autonomous Prefecture and Garze Tibetan Autonomous Prefecture. (3) Analysis based on the local conditions of the TP revealed a high restoration value for three types of grassland (i.e., alpine meadows, mountain meadows, and temperate meadow steppes), the grasslands distributed at altitudes of 3000-4000 m, and the grasslands located in the warm temperate zone. The results of this study are expected to provide scientific and theoretical support for the formulation of policies and measures aimed at conserving grasslands, as well as restoring ecosystems and degraded grasslands on the TP. C1 [Wang, Ruijing; Feng, Qisheng; Jin, Zheren; Liang, Tiangang] Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Engn Res Ctr Grassland Ind,Minist Educ,Coll Pasto, State Key Lab Grassland Agroecosyst,Minist Agr &, Lanzhou 730000, Peoples R China. RP Feng, QS (通讯作者)，Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Engn Res Ctr Grassland Ind,Minist Educ,Coll Pasto, State Key Lab Grassland Agroecosyst,Minist Agr &, Lanzhou 730000, Peoples R China. EM wangrj20@lzu.edu.cn; fengqsh@lzu.edu.cn; jinzhr20@lzu.edu.cn; tgliang@lzu.edu.cn TC 4 Z9 4 PD JAN PY 2022 VL 14 IS 1 AR 80 DI 10.3390/rs14010080 UT WOS:000751439000001 DA 2023-03-23 ER PT J AU Yun, HB Tang, J D'Imperio, L Wang, XB Qu, Y Liu, LC Zhuang, QL Zhang, WX Wu, QB Chen, AP Zhu, Q Chen, DL Elberling, B AF Yun, Hanbo Tang, Jing D'Imperio, Ludovica Wang, Xiaobo Qu, Yang Liu, Licheng Zhuang, Qianlai Zhang, Wenxin Wu, Qingbai Chen, Anping Zhu, Qing Chen, Deliang Elberling, Bo TI Warming and Increased Respiration Have Transformed an Alpine Steppe Ecosystem on the Tibetan Plateau From a Carbon Dioxide Sink Into a Source SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES DT Article AB Cold region ecosystems store vast amounts of soil organic carbon (C), which upon warming and decomposition can affect the C balance and potentially change these ecosystems from C sinks to carbon dioxide (CO2) sources. We quantified the decadal year-round CO2 flux from an alpine steppe-ecosystem on the Tibetan Plateau using eddy covariance and automatic chamber approaches during a period of significant warming (0.13 degrees C per 10 years; and 0.18 degrees C in the non-growing season alone: 1st October to next 30th April). The results showed that ongoing climate change, mainly warming within the topsoil layers, is the main reason for the site's change from a sink for to a source of CO2 in the atmosphere. Non-growing-season ecosystem respiration accounted for 51% of the annual ecosystem respiration and has increased significantly. The growing seasons (1st May to 30th September) were consistent CO2 sink periods without significant changes over the study period. Observations revealed high-emission events from the end of the non-growing season to early in the growing season (1st March to fifteenth May), which significantly (p < 0.01) increased at a rate of 22.6 g C m(-2) decade(-1), ranging from 14.6 +/- 10.7 g C m(-2) yr(-1) in 2012 to 35.3 +/- 12.1 g C m(-2) yr(-1) in 2017. Structural equation modeling suggested that active layer warming was the key factor in explaining changes in ecosystem respiration, leading to significant changes in net ecosystem exchange over the period 2011-2020 and indicated that these changes have already transformed the ecosystem from a CO2 sink into a source. These results can be used to improve our understanding of the sensitivity of ecosystem respiration to increased warming during the non-growing period. C1 [Yun, Hanbo; Wu, Qingbai] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, BeiLuHe Stn, Slate Key Lab Frozen Soil Engn, Lanzhou, Peoples R China. [Yun, Hanbo; D'Imperio, Ludovica; Zhang, Wenxin; Elberling, Bo] Univ Copenhagen, Dept Geosci & Nat Resource Management, Ctr Permafrost CENPERM, Copenhagen, Denmark. [Yun, Hanbo; Zhuang, Qianlai] Purdue Univ, Dept Earth Atmospher & Planetary Sci, W Lafayette, IN 47907 USA. [Tang, Jing; Zhang, Wenxin] Lund Univ, Dept Phys Geog & Ecosyst Sci, Lund, Sweden. [Wang, Xiaobo] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Ecohydrol Inland River Basin, Lanzhou, Peoples R China. [Qu, Yang] East China Normal Univ, Sch Urban & Reg Sci, Shanghai, Peoples R China. [Liu, Licheng] Univ Minnesota, Dept Bioprod & Biosyst Engn, St Paul, MN 55108 USA. [Chen, Anping] Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. [Chen, Anping] Colorado State Univ, Grad Degree Program Ecol, Ft Collins, CO 80523 USA. [Zhu, Qing] Lawrence Berkeley Natl Lab, Climate & Ecosyst Sci Div, Climate Sci Dept, Berkeley, CA USA. [Chen, Deliang] Univ Gothenburg, Dept Earth Sci, Gothenburg, Sweden. RP Wu, QB (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, BeiLuHe Stn, Slate Key Lab Frozen Soil Engn, Lanzhou, Peoples R China.; Elberling, B (通讯作者)，Univ Copenhagen, Dept Geosci & Nat Resource Management, Ctr Permafrost CENPERM, Copenhagen, Denmark.; Chen, AP (通讯作者)，Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. EM qbwu@lzb.ac.cn; apchen1111@gmail.com; be@ign.ku.dk TC 3 Z9 3 PD JAN PY 2022 VL 127 IS 1 AR e2021JG006406 DI 10.1029/2021JG006406 UT WOS:000751889000009 DA 2023-03-23 ER PT J AU Guo, XW Zhou, HK Dai, LC Li, J Zhang, FW Li, YK Lin, L Li, Q Qian, DW Fan, B Lan, YT Si, MK Li, BC Cao, GM Du, YG Wang, B AF Guo, Xiaowei Zhou, Huakun Dai, Licong Li, Jing Zhang, Fawei Li, Yikang Lin, Li Li, Qian Qian, Dawen Fan, Bo Lan, Yuting Si, Mengke Li, Bencuo Cao, Guangmin Du, Yangong Wang, Bin TI Restoration of Degraded Grassland Significantly Improves Water Storage in Alpine Grasslands in the Qinghai-Tibet Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB Alpine grassland has very important water conservation function. Grassland degradation seriously affects the water conservation function; moreover, there is little understanding of the change of water state during grassland restoration. Our study aims to bridge this gap and improve our understanding of changes in soil moisture during the restoration process. In this study, the water storage, vegetation, and meteorology of a non-degradation grassland (grazing intensity of 7.5 sheep/ha) and a severely degraded grassland (grazing intensity of 12-18 sheep/ha) were monitored in the Qinghai-Tibet Plateau for seven consecutive years. We used correlation, stepwise regression, and the boosted regression trees (BRT) model analyses, five environmental factors were considered to be the most important factors affecting water storage. The severely degraded grassland recovered by light grazing treatment for 7 years, with increases in biomass, litter, and vegetation cover, and a soil-water storage capacity 41.9% higher in 2018 compared to that in 2012. This increase in soil-water storage was primarily due to the increase in surface soil moisture content. The key factors that influenced water storage were listed in a decreasing order: air temperature, litter, soil heat flux, precipitation, and wind speed. Their percentage contributions to soil-water storage were 50.52, 24.02, 10.86, 7.82, and 6.77%, respectively. Current and future climate change threatens soil-water conservation in alpine grasslands; however, grassland restoration is an effective solution to improve the soil-water retention capacity in degraded grassland soils. C1 [Guo, Xiaowei; Zhou, Huakun; Li, Jing; Zhang, Fawei; Li, Yikang; Lin, Li; Li, Qian; Qian, Dawen; Fan, Bo; Lan, Yuting; Si, Mengke; Li, Bencuo; Cao, Guangmin; Du, Yangong; Wang, Bin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. [Dai, Licong] Hainan Univ, Coll Ecol & Environm, Haikou, Hainan, Peoples R China. [Wang, Bin] Wagga Wagga Agr Inst, New South Wales Dept Primary Ind, Wagga Wagga, NSW, Australia. RP Du, YG; Wang, B (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China.; Wang, B (通讯作者)，Wagga Wagga Agr Inst, New South Wales Dept Primary Ind, Wagga Wagga, NSW, Australia. EM duyangong@163.com; bin.a.wang@dpi.nsw.gov.au TC 8 Z9 8 PD DEC 16 PY 2021 VL 12 AR 778656 DI 10.3389/fpls.2021.778656 UT WOS:000738450400001 DA 2023-03-23 ER PT J AU Fan, JH Liu, TY Liao, Y Li, YY Yan, Y Lu, XY AF Fan, Jihui Liu, Tianyuan Liao, Ying Li, Yiying Yan, Yan Lu, Xuyang TI Distinguishing Stoichiometric Homeostasis of Soil Microbial Biomass in Alpine Grassland Ecosystems: Evidence From 5,000 km Belt Transect Across Qinghai-Tibet Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB The biogeographic characteristics of soil microbial biomass stoichiometry homeostasis and also its mechanisms are commonly thought to be key factors for the survival strategies and resource utilization of soil microbes under extreme habitat. In this work, we conducted a 5,000-km transect filed survey in alpine grassland across Qinghai-Tibet Plateau in 2015 to measure soil microbial biomass carbon (MBC) and nitrogen (MBN) across alpine steppe and meadow. Based on the differences of climate and soil conditions between alpine steppe and meadow, the variation coefficient was calculated to investigate the homeostatic degree of MBC to MBN. Furthermore, the "trade-off" model was utilized to deeply distinguish the homeostasis degree of MBC/MBN between alpine steppe and meadow, and the regression analysis was used to explore the variability of trade-off in response to environmental factors in the alpine grassland. The results showed that the coefficient of variation (CV) of MBC/MBN in alpine meadow (CV = 0.4) was lower than alpine steppe (CV = 0.7). According to the trade-off model, microbial turnover activity of soil N relative to soil C increased rapidly and then decreased slightly with soil organic carbon (SOC), soil total nitrogen (STN), and soil water content across alpine meadow. Nevertheless, in alpine steppe, SOC/STN had a positive effect on microbial turnover of soil N. These results suggested that water, heat, and soil nutrients availability were the key factors affecting the C:N stoichiometry homeostasis of soil microbial biomass in Qinghai-Tibet Plateau (QTP)'s alpine grassland. Since the difference of survival strategy of the trade-off demands between soil C and N resulting in different patterns and mechanism, the stoichiometry homeostasis of soil microbial biomass was more stable in alpine meadow than in alpine steppe. C1 [Fan, Jihui; Liao, Ying; Li, Yiying; Yan, Yan; Lu, Xuyang] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu, Peoples R China. [Liu, Tianyuan] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China. [Liu, Tianyuan; Liao, Ying; Li, Yiying] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. RP Yan, Y (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu, Peoples R China. EM yy@imde.ac.cn TC 1 Z9 1 PD DEC 2 PY 2021 VL 12 AR 781695 DI 10.3389/fpls.2021.781695 UT WOS:000730870400001 DA 2023-03-23 ER PT J AU Hu, Y Jiang, HM Chen, YC Wang, ZW Yan, Y Sun, P Lu, XY AF Hu, Yang Jiang, Hongmao Chen, Youchao Wang, Ziwei Yan, Yan Sun, Ping Lu, Xuyang TI Nitrogen addition altered the microbial functional potentials of carbon and nitrogen transformation in alpine steppe soils on the Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB The microbial-mediated functional potentials of soil can be reflected by the abundance of corresponding microbial functional genes (MFGs). Few studies have simultaneously examined the responses of multiple key MFGs involving soil carbon (C) and nitrogen (N) transformation to N deposition, particularly under multiple application levels. In this study, we treated the alpine soil from the Tibetan Plateau with N fertilization at six addition rates. Absolute quantitative analysis was used to detect the abundance of MFGs related to soil C process: carbon dioxide (CO2) fixation (cbbL), methane (CH4) oxidation (pmoA) and production (mcrA), and soil N process: ammonia oxidation (AOA-amoA: archaea amoA, AOB-amoA: bacterial amoA), hydroxylamine oxidation (hao), nitrate, nitrite, nitric oxide and nitrous oxide (N2O) reduction (narG/napA, nirS/nirK, norB, and nosZ). The abundance of MFGs involved in both the soil C and N transformation processes were reduced as N rates increased (except AOB-amoA gene). Specifically, the abundance of the mcrA, AOA-amoA, nirK, norB, and nosZ genes were decreased non-linearly (U-shape) with the increasing N rates (P < 0.05). The soil pH and dissolved organic C (DOC) concentration were positively correlated with the abundance of those MFGs, suggesting that the decreases in abundance of MFGs were more likely to be driven by changes of soil pH and DOC concentration. In contrast, the abundance of AOB-amoA gene increased linearly with the increasing N rates, which was strongly and positively correlated with soil nitrate-N (NO3--N) concentration (P < 0.001, r = 0.82). In addition, soil greenhouse gases emissions linked with the abundance of corresponding MFGs. Specifically, the soil CO2 and N2O emissions were strongly and positively correlated with the AOB-amoA gene abundance (P < 0.001, r = 0.78, r = 0.84), and the soil CH4 emissions were significantly correlated with the pmoA (P < 0.01, r = 0.60) and AOA-amoA (P < 0.001, r = 0.72) gene abundance. The above results showed that the AOB-amoA gene had a positive response to increasing N rates, which was different from other genes. Indicating that elevated N deposition may improve the ammonia-oxidation process in alpine steppe soil mediated by AOB communities, and AOB communities may play an important role in donating the soil-atmosphere C and N exchange via CO2 and N2O emissions. C1 [Hu, Yang; Jiang, Hongmao; Wang, Ziwei; Yan, Yan; Lu, Xuyang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Hu, Yang; Jiang, Hongmao; Wang, Ziwei] Univ Chinese Acad Sci, Beijing 100101, Peoples R China. [Chen, Youchao] Chinese Acad Sci, Key Lab Aquat Bot & Watershed Ecol, Wuhan Bot Garden, Wuhan 430074, Peoples R China. [Sun, Ping] Jinling Inst Technol, Nanjing 211169, Peoples R China. RP Lu, XY (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. EM xylu@imde.ac.cn TC 0 Z9 0 PD DEC PY 2021 VL 32 AR e01937 DI 10.1016/j.gecco.2021.e01937 UT WOS:000734884900006 DA 2023-03-23 ER PT J AU Liu, EQ Xiao, XM Shao, HY Yang, X Zhang, YL Yang, Y AF Liu, Enqin Xiao, Xiangming Shao, Huaiyong Yang, Xin Zhang, Yali Yang, Yang TI Climate Change and Livestock Management Drove Extensive Vegetation Recovery in the Qinghai-Tibet Plateau SO REMOTE SENSING DT Article AB The vegetation of the Qinghai-Tibet Plateau (QTP), China, is diverse and sensitive to climate change. Because of extensive grassland degradation in the QTP, several ecological restoration projects, which affect the livestock population, have been implemented in the QTP. Although many studies have reported the impacts of climate change on vegetation in the QTP, our knowledge on the impacts of both climate change and livestock on vegetation remains very limited. Here, we investigated the impacts of climate change and livestock population on vegetation growth by using the annual maximum normalized difference vegetation index (NDVImax) and growing-season climate data from 1981 to 2019. We analyzed the relationship between NDVImax and climate and livestock population using the modified Mann-Kendall trend Test and Pearson correlation analysis. For the entire QTP, NDVImax had a two-phase trend, with a slow rise during 1981-2000 and a rapid rise during 2000-2019. Overall, NDVImax in the QTP increased and decreased in 63.7% and 6.7% of the area in 2000-2019. In areas with significant changes in NDVImax, it was strongly correlated with relative humidity and vapor pressure. The small positive trend in NDVImax during 1981-2000 was influenced by warmer and wetter climate, and the overgrazing by a large population of livestock slowed down the rate of increase in NDVImax. Livestock population for Qinghai and Tibet in recent years has been lower than in the 1980s.The warmer and wetter climate and substantial drops in the livestock population contributed to large recovery in vegetation during 2001-2019. Vegetation degradation in Qinghai during 1981-2000 and central-northern Tibet during 2000-2019 was driven mainly by drier and hotter climatic. Although 63.7% of the area in the QTP became greener, the vegetation degradation in central-northern Tibet should not be ignored and more measures should be taken to alleviate the impact of warming and drying climate. Our findings provide a better understanding of the factors that drove changes in vegetation in the QTP. C1 [Liu, Enqin; Shao, Huaiyong; Yang, Xin; Zhang, Yali; Yang, Yang] Chengdu Univ Technol, Coll Earth Sci, Chengdu 610059, Peoples R China. [Xiao, Xiangming] Univ Oklahoma, Dept Microbiol & Plant Biol, Ctr Earth Observat & Modeling, Norman, OK 73019 USA. RP Xiao, XM (通讯作者)，Univ Oklahoma, Dept Microbiol & Plant Biol, Ctr Earth Observat & Modeling, Norman, OK 73019 USA. EM liuenqin13@mail.cdut.edu.cn; xiangming.xiao@ou.edu; shaohuaiyong@cdut.edu.cn; yangxin2012@cdut.edu.cn; zhangyali@stu.cdut.edu.cn; yy0404@stu.cdut.edu.cn TC 1 Z9 1 PD DEC PY 2021 VL 13 IS 23 AR 4808 DI 10.3390/rs13234808 UT WOS:000734690400001 DA 2023-03-23 ER PT J AU Liu, YM Zhao, F Wang, L He, W Liu, JH Long, YQ AF Liu, Yongmei Zhao, Fan Wang, Lei He, Wei Liu, Jianhong Long, Yongqing TI Spatial Distribution and Influencing Factors of Soil Fungi in a Degraded Alpine Meadow Invaded by Stellera chamaejasme SO AGRICULTURE-BASEL DT Article AB Alpine meadow degradation causes a notable decrease in palatable grasses and an increase in forbs and toxic plants in recent decades. Stellera chamaejasme is one of the most serious toxic weeds, which exerts an increasing threat on alpine meadow in Qinghai-Tibetan Plateau. Combined DNA sequencing with geostatistics was applied to analyze a typical degraded meadow invaded by S. chamaejasme in Qinghai Province, China. The study aimed to determine the spatial variation of soil fungi and its interrelationship with the plant-soil environment. Alpha diversity and relative abundance of fungal phyla and classes showed moderate or strong spatial dependency and were structured in patches of 19-318 m, and taxonomic composition exhibited much higher spatial variability than alpha diversity. Compared to plant cover, the matching of patch size showed a closer spatial link between soil properties and fungal community. Community coverage, SOM, TN, TP, and TK positively correlated to fungal diversity and taxonomic composition; no direct correlation was found between S. chamaejasme coverage and fungal community. The result suggested significant but weak association between plant-soil properties and soil fungal community at local scale. Patchy pattern of S. chamaejasme may disturb spatial variations of soil properties and fungal community, since S. chamaejasme in higher coverage corresponded to lower TK content, which contributed to a decrease in fungal diversity indirectly. C1 [Liu, Yongmei; Wang, Lei; Liu, Jianhong; Long, Yongqing] Northwest Univ, Coll Urban & Environm Sci, Xian 710127, Peoples R China. [Liu, Yongmei; Wang, Lei; Liu, Jianhong; Long, Yongqing] Shaanxi Key Lab Earth Surface Syst & Environm Car, Xian 710127, Peoples R China. [Zhao, Fan] Geovis Technol Co Ltd, Xian 710100, Peoples R China. [He, Wei] Northwest Univ, Coll Life Sci, Xian 710069, Peoples R China. RP Liu, YM (通讯作者)，Northwest Univ, Coll Urban & Environm Sci, Xian 710127, Peoples R China.; Liu, YM (通讯作者)，Shaanxi Key Lab Earth Surface Syst & Environm Car, Xian 710127, Peoples R China. EM liuym@nwu.edu.cn; zhaofan9652@163.com; montez@nwu.edu.cn; weihebio@nwu.edu.cn; jhliu@nwu.edu.cn; sjzxlyq@nwu.edu.cn TC 1 Z9 2 PD DEC PY 2021 VL 11 IS 12 AR 1280 DI 10.3390/agriculture11121280 UT WOS:000735179900001 DA 2023-03-23 ER PT J AU Dong, SK Shang, ZH Gao, JX Boone, R AF Dong, Shikui Shang, Zhanhuan Gao, Jixi Boone, Randall TI Enhancing the ecological services of the Qinghai-Tibetan Plateau's grasslands through sustainable restoration and management in era of global change SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Massive grasslands on the Qinghai-Tibetan Plateau(QTP) provide vital ecosystems services, which have been decreased by land degradation associated with global change. Effective efforts and actions of restoration and management are required to promote the sustainable development of these grassland ecosystems with global importance. This special issue collected numerous papers to address share the innovative theoretical foundations and practical approaches for restoring and protecting QTP's grassland ecosystems in the era of global change. The findings from the collected papers of this special issue stated that the ecosystems services of the QTP's grasslands are declining due to weakened interfaces among soil, plant and grazing animals in the QTP's grassland ecosystems by climate and land use changes. Applicable actions such as climate change mitigation and adaptation, close-to-nature restoration, rotational grazing regime with moderate grazing intensity should be taken to enhance the ecosystem services through rebuilding rational soil-plant-animal interfaces. C1 [Dong, Shikui] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. [Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Gao, Jixi] Minist Environm Protect, Nanjing Inst Environm Protect, Beijing, Peoples R China. [Boone, Randall] Colorado State Univ, Nat Resource Ecol Lab, Ft Collins, CO 80523 USA. RP Dong, SK (通讯作者)，Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. EM dongshikui@bjfu.edu.cn TC 14 Z9 14 PD MAR 1 PY 2022 VL 326 AR 107756 DI 10.1016/j.agee.2021.107756 EA NOV 2021 UT WOS:000744230900009 DA 2023-03-23 ER PT J AU Li, JS Zhao, YQ Shao, XQ Huang, D Shang, JY Li, H He, YX Liu, KS AF Li, Jinsheng Zhao, Yinquan Shao, Xinqing Huang, Ding Shang, Jianying Li, Hui He, Yixuan Liu, Kesi TI The Mixed Addition of Biochar and Nitrogen Improves Soil Properties and Microbial Structure of Moderate-Severe Degraded Alpine Grassland in Qinghai-Tibet Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB The degradation of the grassland system has severely threatened the safety of the ecological environment and animal husbandry. The supplement of key substances lost due to degradation is widely used to accelerate the restoration of the degraded grassland ecosystem. In this study, we investigated the effects of biochar and nitrogen addition on soil properties and microorganisms of degraded alpine grassland. The experimental treatments consisted of the control without any addition, only nitrogen addition (10 gN/m(2)), only biochar addition (4.00 kg/m(2) biochar), and the mixed addition of biochar and nitrogen (4.00 kg/m(2) biochar and 10 gN/m(2) nitrogen, respectively). Adding N alone did not significantly change the pH, total organic carbon (TOC), total nitrogen (TN), microbial biomass (MB), and the composition proportion of microbes of the soil, but increased the contents of soil water content (SWC), NH4+-N, NO3--N, available phosphorus (AP), and the biomass of bacteria and fungi. The addition of biochar or the mixture of biochar and nitrogen increased the contents of pH, TOC, TN, MB, SWC, NH4+-N, NO3--N, AP, bacteria, and fungi in the soil and changed the structure of the soil microbial community. The increasing intensity of AP, bacteria, and fungi under the addition of biochar or the mixture of biochar and nitrogen was significantly greater than that under N addition alone. These results indicated that the separated addition of nitrogen and biochar and the mixed addition of biochar and nitrogen all improved the soil condition of the moderate-severe degraded alpine grassland, but the mixed addition of biochar and nitrogen could be a better strategy to remediate the degraded alpine grassland. C1 [Li, Jinsheng; Shao, Xinqing; Huang, Ding; Li, Hui; He, Yixuan; Liu, Kesi] China Agr Univ, Coll Grassland Sci & Technol, Beijing, Peoples R China. [Zhao, Yinquan] Chengdu Univ Technol, Coll Tourism & Urban Planning, Chengdu, Peoples R China. [Shang, Jianying] China Agr Univ, Coll Land Sci & Technol, Beijing, Peoples R China. [Liu, Kesi] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining, Peoples R China. [Liu, Kesi] Natl Field Stn Grassland Ecosyst, Guyuan, Peoples R China. RP Liu, KS (通讯作者)，China Agr Univ, Coll Grassland Sci & Technol, Beijing, Peoples R China.; Liu, KS (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining, Peoples R China.; Liu, KS (通讯作者)，Natl Field Stn Grassland Ecosyst, Guyuan, Peoples R China. EM kliu@cau.edu.cn TC 4 Z9 4 PD NOV 22 PY 2021 VL 12 AR 765041 DI 10.3389/fpls.2021.765041 UT WOS:000726942100001 DA 2023-03-23 ER PT J AU Dai, LC Fu, RY Guo, XW Du, YG Hu, ZM Cao, GM AF Dai, Licong Fu, Ruiyu Guo, Xiaowei Du, Yangong Hu, Zhongmin Cao, Guangmin TI Alpine shrub had a stronger soil water retention capacity than the alpine meadow on the northeastern Qinghai-Tibetan Plateau SO ECOLOGICAL INDICATORS DT Article AB Soil water retention capacity is an essential component of the land surface processes and hydrological cycles. Although the effect of grassland degradation on soil water retention capacity have been well documented, few studies have focused on how soil hydrological properties vary between different vegetation types on the QinghaiTibet Plateau (QTP). This study selected three vegetation types: Potentilla fruticosa shrub (PFS), Kobresia pygmaca meadow (KPM), and Kobresia humilis meadow (KHM), and aimed to explore the variations and factors controlling soil water retention capacity across the three types. Results showed that the soil water retention capacity was higher in PFS than in KPM and KHM across 0-40 cm, whereas the 0-30 cm plant available water content was much lower in PFS than in KPM and KHM. Meanwhile, the soil properties within the different soil layers varied significantly between vegetation types. The 0-10 cm clay and silt contents were significantly higher in PFS than in the other two vegetation types, whereas the soil bulk density (BD) was lower in PFS than in KHM and KPM. Furthermore, the 0-50 cm soil capillary porosity (CP) was significantly higher in PFS than in KPM and KHM, except at 0-10 cm. Besides, the 0-10 cm soil organic matter (SOM) was significantly higher in KPM than in PFS and KHM, owing to its highest root biomass. Overall, the soil water retention capacity was most strongly influenced by CP, followed by BD, TP, SOM and root biomass, whereas the soil non-capillary porosity and soil particle size distribution exerted no significant impact on soil water retention capacity. Our results suggested that the alpine shrub had a stronger soil water retention capacity than the alpine meadow. C1 [Dai, Licong; Hu, Zhongmin] Hainan Univ, Coll Ecol & Environm, Haikou 570228, Hainan, Peoples R China. [Dai, Licong; Guo, Xiaowei; Du, Yangong; Cao, Guangmin] Chinese Acad Sci, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Northwest Inst Plateau Biol, Xining 810001, Peoples R China. [Dai, Licong; Guo, Xiaowei; Du, Yangong; Cao, Guangmin] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Northwest Inst Plateau Biol, Xining 810001, Qinghai, Peoples R China. [Fu, Ruiyu] Hainan Acad Mangrove, Hainan Acad Forestry, Haikou 571100, Hainan, Peoples R China. RP Dai, LC; Guo, XW (通讯作者)，Chinese Acad Sci, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Northwest Inst Plateau Biol, Xining 810001, Peoples R China. EM licongdai1993@163.com; xwguo1206@163.com TC 2 Z9 2 PD DEC PY 2021 VL 133 AR 108362 DI 10.1016/j.ecolind.2021.108362 EA NOV 2021 UT WOS:000719748000004 DA 2023-03-23 ER PT J AU Ma, CH Xie, YW Duan, HM Wang, XY Bie, Q Guo, ZC He, L Qin, WH AF Ma, Changhui Xie, Yaowen Duan, Hanming Wang, Xiaoyun Bie, Qiang Guo, Zecheng He, Lei Qin, Wenhua TI Spatial quantification method of grassland utilization intensity on the Qinghai-Tibetan Plateau: A case study on the Selinco basin SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Existing methods for spatial quantification of grassland utilization intensity cannot meet the demand for accurate detection of the spatial distribution of grassland utilization intensity in the Qinghai-Tibetan Plateau with high spatial resolution. In this paper, a method based on remote-sensing observations and simulations of grassland growth dynamics is proposed. The grassland enhanced vegetation index (EVI) time-series curve during the growing season characterizes the growth of grassland in the corresponding pixel; The deviation between the observed and potential EVI curves indicates the disturbance on grassland growth imposed by human activities, and it can characterize the grassland utilization intensity during the growing season. Based on the main idea described above, absolute and relative disturbances are calculated and used as quantitative indicators of grassland utilization intensity defined from different perspectives. Livestock amount at the pixel scale is obtained by pixel-by-pixel calculations based on the function relationship at the township scale between absolute disturbance and livestock density, which is specific quantitative indicator that considers the mode of grassland utilization. In simulating the potential EVI of grassland, the lag and accumulation effects of meteorological factors are investigated at the daily scale using a multi-objective genetic algorithm. Further, the nonlinear functions between multiple environmental factors (e.g., grassland type, topography, soil, meteorology) and the grassland EVI are established using an error back-propagation feedforward artificial neural network (ANN-BP) with parameter optimization. Finally, the potential EVIs of all grassland pixels are simulated on the basis of this model. The method is applied to the Selinco basin on the Qinghai-Tibetan Plateau and validated by examining the spatial consistency of the results with township-scale livestock density and grazing pressure. The final results indicate that the proposed method can accurately detect the spatial distribution of grassland utilization intensity which is appliable in the similar regions. C1 [Ma, Changhui; Xie, Yaowen; Duan, Hanming; Wang, Xiaoyun; Bie, Qiang; Guo, Zecheng; He, Lei; Qin, Wenhua] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Gansu, Peoples R China. [Duan, Hanming] China West Normal Univ, Sch Geog Sci, Nanchong 637002, Sichuan, Peoples R China. [Bie, Qiang] Lanzhou Jiaotong Univ, Fac Geomat, Lanzhou 730070, Gansu, Peoples R China. RP Xie, YW (通讯作者)，222 South Tianshui Rd, Lanzhou 730000, Peoples R China. EM mazhh18@lzu.edu.cn; xieyw@lzu.edu.cn TC 4 Z9 4 PD JAN 15 PY 2022 VL 302 AR 114073 DI 10.1016/j.jenvman.2021.114073 EA NOV 2021 PN B UT WOS:000719712200003 DA 2023-03-23 ER PT J AU Pei, JM Yan, D Li, JQ Qiong, L Yang, YW Fang, CM Wu, JH AF Pei, Junmin Yan, Dong Li, Jinquan Qiong, La Yang, Yuanwu Fang, Changming Wu, Jihua TI Alpine meadow degradation enhances the temperature sensitivity of soil carbon decomposition on the Qinghai-Tibetan plateau SO APPLIED SOIL ECOLOGY DT Article AB Grassland degradation is widespread globally, yet limited information is available on the effects and mechanisms of grassland degradation regarding the response of soil organic carbon (SOC) to temperature change. This is especially true for alpine regions, which can have high SOC storage and are extreme vulnerability to global warming. Here, we studied the temperature sensitivity of SOC decomposition (Q(10), proportional change in decomposition rate for a 10 degrees C difference in temperature) in both the topsoil (0-10 cm depth) and subsoil (20-30 cm) along an alpine meadow degradation gradient on the Qinghai-Tibetan plateau (QTP). Q(10) values were increased in response to alpine meadow degradation (severely degraded (2.42) > moderately degraded (2.20) > non-degraded (2.11)) and were higher in subsoil (2.34) than in topsoil (2.14) as a whole. Soil carbon quantity and quality and extracellular enzyme activities all decreased significantly with increasing degradation levels and soil depths. Among all the factors considered (soil texture; soil pH; carbon quantity, availability, and quality; and enzyme activities), Q(10) values were found to be primarily mediated by carbon quality and enzyme activities. This result supported the "carbon-quality temperature" hypothesis in degraded alpine grassland, and that considering soil carbon quality and enzyme activity could improve predictions of the feedbacks between soil carbon and global warming under grassland degradation. Our findings suggest that alpine meadow degradation will further increase the losses of SOC in a warming climate, making the ecosystem more vulnerable to climate change. C1 [Pei, Junmin; Yan, Dong; Li, Jinquan; Yang, Yuanwu; Fang, Changming; Wu, Jihua] Fudan Univ, Minist Educ, Key Lab Biodivers Sci & Ecol Engn,Inst Biodivers, Natl Observat & Res Stn Wetland Ecosyst Yangtze R, Shanghai 200438, Peoples R China. [Pei, Junmin; Yan, Dong; Li, Jinquan; Yang, Yuanwu; Fang, Changming; Wu, Jihua] Fudan Univ, Inst Ecochongming, Sch Life Sci, Shanghai 200438, Peoples R China. [Yan, Dong] China Qual Certificat Ctr, Guangzhou Branch, 161 Linhe West Rd, Guangzhou 510620, Peoples R China. [Qiong, La; Wu, Jihua] Tibet Univ, Res Ctr Ecol, Coll Sci, Tibet Univ Fudan Univ Joint Lab Biodivers & Globa, Lhasa 850000, Peoples R China. [Yang, Yuanwu] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. RP Wu, JH (通讯作者)，Fudan Univ, Sch Life Sci, Inst Biodivers Sci,Natl Observat & Res Stn Wetlan, Minist Educ,Key Lab Biodivers Sci & Ecol Engn, Shanghai 200438, Peoples R China. EM jihuawu@fudan.edu.cn TC 4 Z9 4 PD FEB PY 2022 VL 170 AR 104290 DI 10.1016/j.apsoil.2021.104290 EA NOV 2021 UT WOS:000718052200005 DA 2023-03-23 ER PT J AU Liu, YY Yang, PZ Zhang, ZX Zhang, W Wang, ZQ Zhang, ZY Ren, HY Zhou, RL Wen, ZM Hu, TM AF Liu, Yangyang Yang, Peizhi Zhang, Zhixin Zhang, Wei Wang, Zhenqian Zhang, Zhaoying Ren, Hanyu Zhou, Ronglei Wen, Zhongming Hu, Tianming TI Diverse responses of grassland dynamics to climatic and anthropogenic factors across the different time scale in China SO ECOLOGICAL INDICATORS DT Article AB An accurate quantification in the separation of the relative contributions of climate change and human activities on grassland dynamics is crucial for controlling grassland degradation. Here, we investigated grassland dynamics in China by using net primary productivity (NPP) as an evaluation indicator from 1982 to 2016. We calculated the human-induced grassland NPP (HNPP) by subtracting the potential NPP (PNPP) from the actual NPP (ANPP) to distinguish the climatic and anthropogenic effects on grassland NPP changes across different time scales. Results indicated that the change in grassland ANPP resulted from different dominated factors in the two periods of 1982-1999 and 2000-2016. An obvious increase of grassland ANPP was observed from 1982 to 1999, which mainly due to a slight increasing trend in grassland PNPP driven by a humid-warm climate and a slight decrease in grassland HNPP from weak human activities. An overall increase in ANPP (69.576%) over its decrease portion (30.424%) was observed from 1982 to 1999. Human activities-induced ANPP increase mainly occurred in Shaanxi, Qinghai and Gansu Provinces and Tibet Autonomous Region for the grassland types of Alpine subalpine meadow, Meadow and Slope grassland. Climate-dominated decrease mainly occurred in Shanxi, Shaanxi and Heilongjiang, especially for Plain and Slope grassland. However, an overall decreasing trend of grassland ANPP was observed from 2000 to 2016, mainly attributed to a decreasing trend in grassland HNPP by human intervention and a warm-dry climate-induced negative effect on grassland growth. Overall, the grassland underwent a decrease than increase in ANPP (58.826% vs 41.174%) during 2000-2016; the contributions of climate factors to grassland ANPP increase was relatively greater than that of human factors in Xinjiang, Qinghai and Inner Mongolia. Human activities-dominated ANPP decrease occupied 23.913%, obviously higher than the decrease dominated by climate change (9.248%), which mainly occurred in Alpine subalpine meadow, Desert grassland and Alpine subalpine grassland. Overall, these findings seem to demonstrate that there are great differences in the temporal and spatial effects of climate change and human activities on different regions and different grassland types in China before and after 1999, and contribute to providing location guidance for future grassland restoration. Meanwhile, this study is expected to improve the understanding of the driving mechanisms of grassland dynamics, and provide support for scientifically evaluating and adjusting ecological restoration policies in China. C1 [Liu, Yangyang; Yang, Peizhi; Zhang, Zhixin; Zhang, Wei; Ren, Hanyu; Zhou, Ronglei; Wen, Zhongming; Hu, Tianming] Northwest A&F Univ, Coll Grassland Agr, Yangling 712100, Shaanxi, Peoples R China. [Wang, Zhenqian] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Peoples R China. [Zhang, Zhaoying] Nanjing Univ, Jiangsu Prov Key Lab Geog Informat Sci & Technol, Int Inst Earth Syst Sci, Nanjing 210023, Peoples R China. RP Wen, ZM; Hu, TM (通讯作者)，Northwest A&F Univ, Coll Grassland Agr, Yangling 712100, Shaanxi, Peoples R China. EM zhaoying_zhang@163.com; zmwen@ms.iswc.ac.cn; hutianming@126.com TC 3 Z9 3 PD DEC PY 2021 VL 132 AR 108341 DI 10.1016/j.ecolind.2021.108341 EA NOV 2021 UT WOS:000719776000007 DA 2023-03-23 ER PT J AU Liu, N Ding, YX Peng, SZ AF Liu, Ning Ding, Yongxia Peng, Shouzhang TI Temporal effects of climate on vegetation trigger the response biases of vegetation to human activities SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Quantitatively distinguishing the effects of human activities and climate change on vegetation change is crucial for planning scientific vegetation management measures. Previous studies have employed the residual trend method (RESTREND) and remote sensing data to address this issue. However, the mathematical relationships between climate and remote sensing vegetation index under RESTREND are variable and not comprehensively described due to temporal effects of climate on vegetation. Using Tibetan Plateau (TP), this study investigated how the temporal effects of climate on vegetation trigger response biases of vegetation to human activities under four temporal effects (no temporal effect [No], temporal lag effect [Lag], temporal accumulation effect [Acc], and both temporal lag and temporal accumulation effects [Lagacc]). The results revealed the following. (1) The mean explanation degrees of climatic factors to vegetation growth over entire TP under No, Lag, Acc, and Lagacc effects were 0.41 +/- 0.02, 0.42 +/- 0.02, 0.44 +/- 0.02, and 0.47 +/- 0.02, respectively. Therefore, the Lagacc effect is the best temporal effect for establishing the vegetation-climate relationships. (2) Under the Lagacc effect, the temperature exhibited 1.60 +/- 0.13 months lag and 4.56 +/- 0.28 months accumulation on vegetation growth over entire the TP, whereas the precipitation exhibited 1.57 +/- 0.16 months lag and 4.99 +/- 0.31 months accumulation. Furthermore, the grids affected by the combined temporal lag and temporal accumulation effects of climatic factors accounted for 43.42-45.78% of the total grids. These indicated the temporal effects of climate on vegetation, and vegetation growth was largely affected by the combined temporal effects of climatic factors. (3) Under the Lagacc effect, 11.6% of the region experienced significant residual increase, and the slope of the residual was 22.2 x 10(-4), which was primarily distributed in the north and southeast of the TP. However, the area and slope of significant residual decrease were 1.3% and 24.0 x 10(-4), respectively, which were primarily distributed in the center of the TP. Furthermore, the average contributions of human activities on vegetation growth in the regions of residual significant increase and decrease were 54.5% and 55.5%, respectively. Therefore, the Lagacc effect exhibited the smallest influence area and the lowest influence degree for the contribution of human activities on vegetation growth. We thus suggest that the Lagacc effect should be fully considered when establishing the mathematical relationship between climatic factors and the vegetation index. C1 [Liu, Ning] Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. [Liu, Ning] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Ding, Yongxia] Baoji Univ Arts & Sci, Coll Geog & Environm, Shaanxi Key Lab Disasters Monitoring & Mech Simul, Baoji 721013, Peoples R China. [Peng, Shouzhang] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. RP Peng, SZ (通讯作者)，Inst Soil & Water Conservat, 26 Xinong Rd, Yangling 712100, Shaanxi, Peoples R China. EM szp@nwafu.edu.cn TC 6 Z9 6 PD NOV PY 2021 VL 31 AR e01827 DI 10.1016/j.gecco.2021.e01822 UT WOS:000697669600001 DA 2023-03-23 ER PT J AU Niu, YL Li, SY Liu, Y Shi, JJ Wang, YL Ma, YS Wu, GL AF Niu, Yali Li, Shuyuan Liu, Yu Shi, Jianjun Wang, Yanlong Ma, Yushou Wu, Gao-Lin TI Regulation of alpine meadow patch coverage on runoff and sediment under natural rainfall on the eastern Qinghai-Tibetan Plateau SO JOURNAL OF HYDROLOGY DT Article AB Soil and water conservation is the most important among ecological functions of alpine meadow on the Qinghai-Tibetan Plateau. Quantitative assessment of the effects of meadow patch coverage (MPC) on the runoff and sediment processes in alpine meadow is urgent for predicting the water conservation function of this special alpine ecosystem. Here, a field experiment was conducted to determine the effects of different meadow patch coverage through runoff and sediment processes in a typical alpine meadow on the eastern Qinghai-Tibetan Plateau. The results showed that runoff in 30% and 60% MPC plots were 39.4% and 37.9% less than in 90% MPC plot, respectively. The sediment yield in 60% and 90% MPC plots were 77.9% and 82.1% less than in 30% MPC plot, respectively. The sediment concentration in 30% MPC in heavy rainfall scenario is 4.34 times and 6.51 times higher than that in light rainfall scenario and moderate rainfall scenario, respectively. Our results indicated that MPC presented a greater impact on sediment yield than runoff volume, although runoff was greatly affected by rainfall. The higher MPC followed the greater runoff coefficient and the lower sediment concentration. The influences of MPC on runoff and sediment yield in light rainfall scenario and moderate rainfall scenario were weaker than those in heavy rainfall scenario. It is necessary to maintain surface runoff while controlling soil loss for realizing the sustainability of alpine meadow ecosystems. Therefore, these findings may conducive to offer a theoretical guidance to achieve the combined goal of soil erosion regulation during alpine meadow degradation on the Qinghai-Tibetan Plateau. C1 [Niu, Yali; Li, Shuyuan; Liu, Yu; Wu, Gao-Lin] Northwest A&F Univ, Coll Nat Resources & Environm, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Liu, Yu] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. [Liu, Yu; Shi, Jianjun; Wang, Yanlong; Ma, Yushou; Wu, Gao-Lin] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Qinghai Prov Key Lab Adapt Management Alpine Gras, Xining 810016, Peoples R China. RP Liu, Y; Wu, GL (通讯作者)，Northwest A&F Univ, Inst Soil & Water Conservat, 26 Xinong Rd, Yangling 712100, Shaanxi, Peoples R China. EM kingliuyu@nwafu.edu.cn; wugaolin@nwsuaf.edu.cn TC 10 Z9 10 PD DEC PY 2021 VL 603 AR 127101 DI 10.1016/j.jhydrol.2021.127101 EA OCT 2021 PN C UT WOS:000715326800031 DA 2023-03-23 ER PT J AU Gao, WL Sun, WM Xu, XL AF Gao, Wenlong Sun, Weimin Xu, Xingliang TI Permafrost response to temperature rise in carbon and nutrient cycling: Effects from habitat-specific conditions and factors of warming SO ECOLOGY AND EVOLUTION DT Article AB Permafrost is experiencing climate warming at a rate that is two times faster than the rest of the Earth's surface. However, it is still lack of a quantitative basis for predicting the functional stability of permafrost ecosystems in carbon (C) and nutrient cycling. We compiled the data of 708 observations from 89 air-warming experiments in the Northern Hemisphere and characterized the general effects of temperature increase on permafrost C exchange and balance, biomass production, microbial biomass, soil nutrients, and vegetation N dynamics through a meta-analysis. Also, an investigation was made on how responses might change with habitat-specific (e.g., plant functional groups and soil moisture status) conditions and warming variables (e.g., warming phases, levels, and timing). The net ecosystem C exchange (NEE) was found to be downregulated by warming as a result of a stronger sensitivity to warming in respiration (15.6%) than in photosynthesis (6.2%). Vegetation usually responded to warming by investing more C to the belowground, as belowground biomass increased much more (30.1%) than aboveground biomass (2.9%). Warming had a minor effect on microbial biomass. Warming increased soil ammonium and nitrate concentrations. What's more, a synthesis of 70 observations from 11 herbs and 9 shrubs revealed a 2.5% decline of N in green leaves. Compared with herbs, shrubs had a stronger response to respiration and had a decline in green leaf N to a greater extent. Not only in dry condition did green leaf N decline with warming but also in wet conditions. Warming in nongrowing seasons would negatively affect soil water, C uptake, and biomass production during growing seasons. Permafrost C loss and vegetation N decline may increase with warming levels and timing. Overall, these findings suggest that besides a positive C cycling-climate feedback, there will be a negative feedback between permafrost nutrient cycling and climate warming. C1 [Gao, Wenlong; Sun, Weimin] Guangdong Acad Sci, Natl Reg Joint Engn Res Ctr Soil Pollut Control &, Inst Ecoenvironm & Soil Sci, Guangdong Key Lab Integrated Agroenvironm Pollut, Guangzhou, Peoples R China. [Gao, Wenlong] Chinese Acad Trop Agr Sci, Environm & Plant Protect Inst, Hainan Key Lab Trop Ecocircular Agr, Haikou, Hainan, Peoples R China. [Gao, Wenlong] Hainan Danzhou Trop Agroecosyst Natl Observat & R, Danzhou, Peoples R China. [Sun, Weimin] Henan Normal Univ, Sch Environm, Xinxiang, Henan, Peoples R China. [Sun, Weimin] Minist Educ, Key Lab Yellow River & Huai River Water Environm, Beijing, Peoples R China. [Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. RP Xu, XL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. EM xuxingl@hotmail.com TC 2 Z9 2 PD NOV PY 2021 VL 11 IS 22 BP 16021 EP 16033 DI 10.1002/ece3.8271 EA OCT 2021 UT WOS:000711727200001 DA 2023-03-23 ER PT J AU Zhang, L Wang, XT Wang, J Wan, Q Liao, LR Liu, GB Zhang, C AF Zhang, Lu Wang, Xiangtao Wang, Jie Wan, Qian Liao, Lirong Liu, Guobin Zhang, Chao TI Effects of alpine meadow degradation on nitrifying and denitrifying microbial communities, and N2O emissions on the Tibetan Plateau SO SOIL RESEARCH DT Article AB Meadow degradation is often accompanied by significant changes in nitrogen (N)-cycling and nitrous oxide (N2O) emission potential, and leads to challenges in meadow management. However, the mechanisms of soil N-cycling and N2O emissions remain poorly understood, especially in alpine ecosystems. In this study, we investigated the soil N-cycling process in four alpine meadows on the Tibetan Plateau along a degradation gradient using real-time quantitative polymerase chain reaction and amplicon sequencing to elucidate the mechanisms. Compared to non-degraded meadows, meadow degradation reduced N2O emissions by 38.5-140.2%. Meadow degradation reduced the abundance of amoA of ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB), whereas light and moderate degradation increased the abundance of genes nirS, nirK, and nosZ. Lightly degraded meadow exhibited the highest alpha-diversity of both nitrifiers and denitrifiers, but this higher diversity was not accompanied by higher N2O emissions, with only 32.3% of the microbial taxa identified as predictors of N2O emissions, suggesting that functional redundancy exists in the N-cycling process in meadow ecosystems. Nitrosospira and Mesorhizobium from the AOB and nirK communities, respectively, were identified as the key taxa that may contribute to N2O emissions. Soil properties, especially N reaction substrates, including ammonium-N, nitrate-N, dissolved organic N, and total N, were the primary drivers for N2O emissions via mediation of the N-cycling community, especially nitrifiers. Our results emphasised the importance of environmental factors in shaping nitrifying, denitrifying, and N2O emissions, providing insights for the restoration of degraded meadow ecosystems. C1 [Zhang, Lu; Liao, Lirong; Liu, Guobin; Zhang, Chao] Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Zhang, Lu; Liao, Lirong] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Xiangtao] Xizang Agr & Anim Husb Coll, Dept Anim Sci, Linzhi 860000, Peoples R China. [Wang, Jie; Wan, Qian; Liu, Guobin; Zhang, Chao] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. RP Zhang, C (通讯作者)，Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. EM zhangchaolynn@163.com TC 1 Z9 1 PY 2022 VL 60 IS 2 BP 158 EP 172 DI 10.1071/SR21097 EA OCT 2021 UT WOS:000710422400001 DA 2023-03-23 ER PT J AU Ji, SN Cui, SJ Lv, WW Wang, WY Li, BW Liu, PP Huan, H Yang, Z Qi, W Jiang, LL Dorji, T Wang, SP AF Ji Suonan Cui, Shujuan Lv, Wangwang Wang, Wenying Li, Bowen Liu, Peipei Huan Hong Yang Zhou Qi Wang Jiang, Lili Dorji, Tsechoe Wang, Shiping TI Degradation rather than warming delays onset of reproductive phenology of annual Chenopodium glaucum on the Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB With degradation and desertification of alpine meadows due to climate warming and overgrazing, the distribution of annual plant species has greatly expanded on the Tibetan Plateau. Most phenological studies in the past decades have mainly focused on perennial plants, and few have studied the phenology of annual plants, despite their different life history. Lack of knowledge regarding how phenological sequences of annual plants respond to climatic warming in degraded areas limits our ability to restore and protect degraded alpine ecosystems under future warming. To study the independent and interactive effects of degradation and warming on the phenological sequences of the annual plant, Chenopodium glaucum, we conducted a two-factor control experiment (degradation: moderate and severe degradation; warming: non-warming and open-top chamber warming) on the Tibetan Plateau during 2014-2016. Our results indicated that out of six phenophases of the annual plant warming only delayed first fruit setting. However, degradation delayed the onset of reproductive phenology of the annual plant, which may cause by decreased soil nutrient, above-ground biomass and richness led by degradation. Furthermore, the independent and interactive effects of degradation and warming on phenological events showed significant interannual variation. Given the vital role of C. glaucum on colonizing desertified ground and promoting vegetation restoration, these mechanisms may be essential for the persistence of the species in the highly degraded alpine meadows on the Tibetan Plateau. C1 [Ji Suonan; Lv, Wangwang; Li, Bowen; Liu, Peipei; Huan Hong; Yang Zhou; Qi Wang; Jiang, Lili; Dorji, Tsechoe; Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Sci, Climate Change & Ecosyst Funct Grp, 16 Lincui Rd, Beijing 100101, Peoples R China. [Ji Suonan; Wang, Wenying] Qinghai Normal Univ, Coll Life Sci, Haihu Rd, Xining 810016, Peoples R China. [Ji Suonan; Wang, Wenying] Acad Plateau Sci & Sustainabil, Haihu Rd, Xining 810016, Peoples R China. [Cui, Shujuan] Anqing Normal Univ, Coll Resources & Environm, 1318 North Jixian Rd, Anqing 246133, Peoples R China. [Lv, Wangwang; Li, Bowen; Liu, Peipei; Huan Hong; Yang Zhou; Qi Wang; Jiang, Lili; Dorji, Tsechoe; Wang, Shiping] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Dorji, Tsechoe; Wang, Shiping] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Sci, Climate Change & Ecosyst Funct Grp, 16 Lincui Rd, Beijing 100101, Peoples R China.; Wang, SP (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China.; Wang, SP (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. EM wangsp@itpcas.ac.cn TC 0 Z9 0 PD DEC 15 PY 2021 VL 311 AR 108688 DI 10.1016/j.agrformet.2021.108688 EA OCT 2021 UT WOS:000710990900009 DA 2023-03-23 ER PT J AU He, MR Xin, CM Ma, MJ AF He, Mingrui Xin, Chunming Ma, Miaojun TI Change in grass hill size can signal species diversity changes and ecosystem state transitions during alpine wetland degradation SO ECOLOGICAL INDICATORS DT Article AB The prospect of likely catastrophic transitions in ecosystems requires the development of early warning indicators that will provide advance warnings for undesired transitions. A grass hill is a unique microtopography that plays a crucial role in the functioning of wetland ecosystems. However, it is unclear whether grass hill size could serve as an important warning indicator to predict vegetation dynamics and ecosystem transitions during wetland degradation. Six degradation levels were selected along a grazing gradient in the alpine wetlands on the eastern Tibetan Plateau. General linear and segment regression were used to analyze whether grass hill area (GHA) can be used as an important warning indicator to predict biotic and abiotic factors and ecosystem transitions from typical alpine wetlands to meadows. The species diversity and biomass of aboveground vegetation increased slowly before the threshold point but decreased sharply after the threshold point (GHA (grass hill area) = 0.13 m2). The species diversity of both persistent and transient seed banks and the seed density of persistent seed banks also increased slowly but increased sharply before and after the threshold point (GHA = 0.2 m2). Soil moisture (SM), soil organic carbon (SOC) and total nitrogen (TN) decreased slowly but decreased sharply before and after the threshold point (GHA > 0.2 m2). Surprisingly, we also found the same threshold point (GHA = 0.13-0.2 m2) for the ecosystem transition from alpine wetlands to meadows as that for the other factors. GHA accurately predicted biotic (species diversity of vegetation and seed bank) and abiotic (SM, SOC, and TN) changes and the ecosystem transition from alpine wetlands to meadows. Thus, grass hill area is an effective warning indicator that could be used in future alpine wetland restoration and management. C1 [He, Mingrui; Xin, Chunming; Ma, Miaojun] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. RP Ma, MJ (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. EM hemr18@lzu.edu.cn; xinchm17@lzu.edu.cn; mjma@lzu.edu.cn TC 2 Z9 2 PD DEC PY 2021 VL 132 AR 108302 DI 10.1016/j.ecolind.2021.108302 EA OCT 2021 UT WOS:000710621100002 DA 2023-03-23 ER PT J AU Hu, J Chen, GR Hassan, WM Lan, JN Si, WT Wang, W Li, GX Du, GZ AF Hu, Jing Chen, Guorong Hassan, Wail M. Lan, Jianbin Si, Wantong Wang, Wei Li, Guixin Du, Guozhen TI The impact of fertilization intensity on soil nematode communities in a Tibetan Plateau grassland ecosystem SO APPLIED SOIL ECOLOGY DT Article AB Tibetan Plateau grasslands embody an important ecosystem featuring vibrant biogeochemical cycles. Soil fauna, particularly nematodes, play an important role in maintaining the integrity, function, and homeostasis of such ecosystem. In the Tibetan Plateau, studies exploring the influence of frequent fertilization practices on nematode communities and subsequent repercussions impacting the entire ecosystem are scarce. To investigate the effect of long-term fertilization on nematode communities in the eastern Tibetan Plateau of China, we monitored such communities under fertilization treatments ranging from 0 to 120 g m(-2) year(-1). To gain broader insights into the dynamic interrelationships within the ecosystem, we also monitored plant communities and modeled their bidirectional relationships with soil nematodes. Our data show that with higher fertilization intensities, overall plant productivity increases. Such gains are accompanied by reduction in plant community richness and predominance of grasses on the expense of sedges, legumes, and forbs. Fertilization also impacted the abundance and species richness of nematode communities; this effect was manifest in a hump-shaped relationship with both abundance and species richness of nematode communities peaking at 60 g m(-2) year(-1). The relationship between nematode biodiversity and aboveground plant production also exhibited a predominantly hump-shaped trajectory. Our model suggests that soil acidity and the ratio of available nitrogen-to-available phosphorus had indirect, yet strong, effects on the nematode community abundance and species richness, indicating that the decline of nematode communities beyond a 60 g m(-2) year(-1) treatment could, at least in part, be attributed to unfavorable soil conditions. Our findings augment our understanding of the responses of soil fauna to nitrogen and phosphorus additions in alpine grasslands and provide scientific basis for future management of grassland fertilization. C1 [Hu, Jing; Lan, Jianbin; Wang, Wei] Chongqing Univ Arts & Sci, Inst Special Plants, Coll Landscape Architecture & Life Sci, Chongqing 402160, Peoples R China. [Hu, Jing; Li, Guixin; Du, Guozhen] Lanzhou Univ, Sch Life Sci, Lanzhou 730000, Peoples R China. [Chen, Guorong; Si, Wantong] Chongqing Univ Arts & Sci, Coll Chem & Environm Engn, Chongqing 402160, Peoples R China. [Hassan, Wail M.] Univ Missouri, Sch Med, Dept Biomed Sci, Kansas City, MO 64108 USA. RP Hu, J (通讯作者)，Chongqing Univ Arts & Sci, Inst Special Plants, Coll Landscape Architecture & Life Sci, Chongqing 402160, Peoples R China.; Hu, J; Du, GZ (通讯作者)，Lanzhou Univ, Sch Life Sci, Lanzhou 730000, Peoples R China. EM 20170008@cqwu.edu.cn; guozhendu@lzu.edu.cn TC 1 Z9 1 PD FEB PY 2022 VL 170 AR 104258 DI 10.1016/j.apsoil.2021.104258 EA OCT 2021 UT WOS:000711839700012 DA 2023-03-23 ER PT J AU Lai, CM Li, CY Peng, F Xue, X You, QG Zhang, WJ Ma, SX AF Lai, Chimin Li, Chengyang Peng, Fei Xue, Xian You, Quangang Zhang, Wenjuan Ma, Shaoxiu TI Plant community change mediated heterotrophic respiration increase explains soil organic carbon loss before moderate degradation of alpine meadow SO LAND DEGRADATION & DEVELOPMENT DT Article AB Alpine meadows on the Qinghai-Tibet Plateau (QTP) store a huge amount of plant and soil carbon (C). The degradation of the alpine meadow has led to a significant loss of soil organic C (SOC), which endangers its weak C sink. The change in heterotrophic respiration was hypothesized as one of the primary biological processes for the SOC loss alongside the degradation of alpine meadow. However, little is known about how land degradation impacts R-h due to changes in plant communities and consequent labile organic C inputs. R-h, vegetation productivity, plant community composition, plant lignin concentration, leaf C/N, SOC, and soil labile C (SLC) were measured for alpine meadow grasslands with five degradation levels in 2 years. Our results showed that the SOC of the surface layer (0-10 cm) gradually decreased with land degradation. The plant lignin concentration and C/N ratio gradually increased with land degradation due to the proportion of sedges decreased while that of forbs increased, which consequently led to the soil C quality (SLC) increased before the moderate degradation level (MD) while significantly reduced in severe and very severe degradation levels (SD and VSD). The structural equation modeling result (SEM) revealed that the degradation-induced change in soil C quality (SLC) due to an alteration in plant community composition relates to the R-h change with grassland degradation, and the R-h (C output) and aboveground biomass (AGB: C input) further mediated the loss of SOC alongside alpine meadow degradation. On average, R-h increased by 49% and 59% from the Intact to slight degradation level (SLD) and MD and reduced by 56% and 69% from MD to SD and VSD. The temperature sensitivity of R-h (Q(10)) was higher in the SLD (Q(10) = 2.84) and MD (Q(10) = 2.62) comparing with the Intact (Q(10) = 2.58) respectively, but it was lower in SD (Q(10) = 2.19) and VSD (Q(10) = 1.65). AGB and belowground net primary productivity (BNPP) had no significant change until the MD, while reduced by 60%-90% in SD and VSD. Our results suggest that R-h and its Q(10) change moderated by soil C quality alteration due to the plant community shifting could be one mechanism for the soil C loss before MD, but could not be the main pathway for the SOC loss at SD and VSD. C1 [Lai, Chimin; Li, Chengyang; Peng, Fei; Xue, Xian; You, Quangang; Ma, Shaoxiu] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. [Lai, Chimin; Li, Chengyang] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Peng, Fei] Tottori Univ, Int Platform Dryland Res & Educ, Tottori, Japan. [Zhang, Wenjuan] Lanzhou Univ Arts & Sci, Sch Tourism, Lanzhou, Peoples R China. RP Peng, F (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. EM pengfei@lzb.ac.cn TC 4 Z9 4 PD DEC PY 2021 VL 32 IS 18 BP 5322 EP 5333 DI 10.1002/ldr.4111 EA OCT 2021 UT WOS:000707194500001 DA 2023-03-23 ER PT J AU Qian, DW Li, Q Fan, B Lan, YT Cao, GM AF Qian, Dawen Li, Qian Fan, Bo Lan, Yuting Cao, Guangmin TI Characterization of the spatial distribution of plateau pika burrows along an alpine grassland degradation gradient on the Qinghai-Tibet Plateau SO ECOLOGY AND EVOLUTION DT Article AB Plateau pika burrows are common feature of degraded grassland in the Qinghai-Tibet Plateau (QTP) and serve as an important indicator of pika activity and grassland degradation. However, the current understanding of the spatial pattern changes of pika burrows and their critical thresholds across a degradation gradient in alpine grassland is deficient. In this study, we investigated and quantified changes in the spatial pattern of plateau pika burrows under typical degraded alpine shrub meadows in the northeastern QTP using an unmanned aerial vehicle and landscape pattern metrics. The degradation of the alpine shrub meadow leads to a change in landscape pattern from a two-layered structure of alpine shrub and alpine meadow to a mosaic of alpine meadow and bare soil, with plateau pika burrows scattered throughout. Moderate degradation is the tipping point for changes in surface landscape patterns, followed by the disappearance of alpine shrub, the retreat of alpine meadows and the encroachment of bare soil, and the increasing density and size of pika burrows. The area characteristics of alpine meadows have influenced changes in the spatial pattern of pika burrow, and maintaining its proportional area is a vital measure to control the threat of pika burrows to pastures. The results of this paper provide a methodological reference and guidance for the sustainable utilization of grassland on the QTP. C1 [Qian, Dawen; Li, Qian; Fan, Bo; Lan, Yuting; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, 23 Xinning Rd, Xining 810008, Qinghai, Peoples R China. RP Qian, DW (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, 23 Xinning Rd, Xining 810008, Qinghai, Peoples R China. EM dwqian@nwipb.cas.cn TC 1 Z9 1 PD NOV PY 2021 VL 11 IS 21 BP 14905 EP 14915 DI 10.1002/ece3.8176 EA OCT 2021 UT WOS:000704913400001 DA 2023-03-23 ER PT J AU Jiang, YS Zhang, DY Ostle, NJ Luo, CL Wang, Y Ding, P Cheng, ZN Shen, CD Zhang, G AF Jiang, Yishan Zhang, Dayi Ostle, Nicholas J. Luo, Chunling Wang, Yan Ding, Ping Cheng, Zhineng Shen, Chengde Zhang, Gan TI FLEXIBLE SOIL MICROBIAL CARBON METABOLISM ACROSS AN ASIAN ELEVATION GRADIENT SO RADIOCARBON DT Article AB The function and change of global soil carbon (C) reserves in natural ecosystems are key regulators of future carbon-climate coupling. Microbes play a critical role in soil carbon cycling and yet there is poor understanding of their roles and C metabolism flexibility in many ecosystems. We wanted to determine whether vegetation type and climate zone influence soil microbial community composition (fungi and bacteria) and carbon resource preference. We used a biomarker (phospholipid fatty acids, PLFAs), natural abundance C-13 and C-14 probing approach to measure soil microbial composition and C resource use, along a 1900-4167-m elevation gradient on Mount Gongga (7556 m asl), China. Mount Gongga has a vertical mean annual temperature gradient of 1.2-10.1 degrees C and a diversity of typical vegetation zones in the Tibetan Plateau. Soils were sampled at 10 locations along the gradient capturing distinct vegetation types and climate zones from lowland subtropical-forest to alpine-meadow. PLFA results showed that microbial communities were composed of 2.1-51.7% bacteria and 2.0-23.2% fungi across the elevation gradient. Microbial biomass was higher and the ratio of soil fungi to bacteria (F/B) was lower in forest soils compared to meadow soils. delta C-13 varied between -33 parts per thousand to -17 parts per thousand with C3 plant carbon sources dominant across the gradient. Soil organic carbon (SOC) turnover did not vary among three soils we measured from three forest types (i.e., evergreen broadleaved subtropical, mixed temperate, coniferous alpine) and dissolved organic carbon (DOC) turnover decreased with soil elevation. Forest soil microbial PLFA C-14 and delta C-13 measurements showed that forest type and climate were related to different microbial C use. The C-14 values of microbial PLFAs i15, a15, 16:1, br17 decreased with elevation while those of C16:0, cyC17, and cyC19 did not show much difference among three forest ecosystems. Bacteria and bacillus represented by C16:1 and brC17 showed considerable microbial C metabolism flexibility and tended to use ancient carbon at higher altitudes. Anaerobes represented by cyC17 and cyC19 showed stronger C metabolism selectivity. Our findings reveal specific C source differences between and within soil microbial groups along elevation gradients. C1 [Jiang, Yishan; Luo, Chunling; Cheng, Zhineng; Zhang, Gan] Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Organ Geochem, Guangzhou 510640, Peoples R China. [Jiang, Yishan; Luo, Chunling; Cheng, Zhineng; Zhang, Gan] Chinese Acad Sci, Guangzhou Inst Geochem, Guangdong Hong Kong Macao Joint Lab Environm Poll, Guangzhou 510640, Peoples R China. [Jiang, Yishan; Luo, Chunling; Ding, Ping; Cheng, Zhineng; Shen, Chengde; Zhang, Gan] CAS Ctr Excellence Deep Earth Sci, Guangzhou 510640, Peoples R China. [Jiang, Yishan] Wuhan Univ Sci & Technol, Acad Green Mfg Engn, Wuhan 430081, Peoples R China. [Zhang, Dayi] Tsinghua Univ, Sch Environm, Beijing 100084, Peoples R China. [Ostle, Nicholas J.] Univ Lancaster, Lancaster Environm Ctr, Lancaster LA1 4YQ, Lancs, England. [Luo, Chunling] South China Agr Univ, Coll Nat Resources & Environm, Guangzhou 510642, Peoples R China. [Wang, Yan] Dalian Univ Technol, Sch Environm Sci & Technol, Dalian 116024, Peoples R China. [Ding, Ping; Shen, Chengde] Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Peoples R China. RP Luo, CL; Zhang, G (通讯作者)，Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Organ Geochem, Guangzhou 510640, Peoples R China.; Luo, CL; Zhang, G (通讯作者)，Chinese Acad Sci, Guangzhou Inst Geochem, Guangdong Hong Kong Macao Joint Lab Environm Poll, Guangzhou 510640, Peoples R China.; Luo, CL; Zhang, G (通讯作者)，CAS Ctr Excellence Deep Earth Sci, Guangzhou 510640, Peoples R China.; Luo, CL (通讯作者)，South China Agr Univ, Coll Nat Resources & Environm, Guangzhou 510642, Peoples R China. EM clluo@gig.ac.cn; zhanggan@gig.ac.cn TC 0 Z9 0 PD OCT PY 2021 VL 63 IS 5 BP 1397 EP 1413 DI 10.1017/RDC.2021.57 UT WOS:000718989700003 DA 2023-03-23 ER PT J AU Xiang, ZY Bhatt, A Tang, ZB Peng, YS Wu, WF Zhang, JX Wang, JX Gallacher, D Zhou, SX AF Xiang, Zeyu Bhatt, Arvind Tang, Zhongbin Peng, Yansong Wu, Weifeng Zhang, Jiaxin Wang, Jingxuan Gallacher, David Zhou, Saixia TI Disturbance of plateau zokor-made mound stimulates plant community regeneration in the Qinghai-Tibetan Plateau, China SO JOURNAL OF ARID LAND DT Article AB Mounds constructed by plateau zokors, which is widely distributed in alpine meadows significantly modified plant community structure. However, the variations of plant community structure under the disturbance of plateau zokor-made mound are less concerned. Therefore, we investigated the responses of plant community on zokor-made mound of different years (1 a and 3-4 a), and compared with undisturbed sites (no mound) in an alpine meadow in the eastern Qinghai-Tibetan Plateau (QTP), China. Species richness, coverage and Simpson diversity index were all significantly reduced by the presence of zokor-made mound, but plant heights were significantly increased, particularly in grasses and sedges. Several perennial forage species showed an increased importance value and niche breadth, including Koeleria macrantha, Elymus nutans and Poa pratensis. The effect of zokor-made mound on niche overlap showed that more intense interspecific competition produced a greater utilization of environmental resources. And this interspecific niche overlap was strengthened as succession progressed. The bare mound created by zokor burrowing activities provided a colonizing opportunity for non-dominant forage species, resulting in abundant plant species and plant diversity during the succession period. We concluded that presence of zokor-made mound was conducive to regeneration and vitality of plant community in alpine meadows, thus improving their resilience to anthropogenic stress. C1 [Xiang, Zeyu; Bhatt, Arvind; Tang, Zhongbin; Peng, Yansong; Wu, Weifeng; Zhang, Jiaxin; Wang, Jingxuan; Zhou, Saixia] Chinese Acad Sci, Lushan Bot Garden, Jiujiang 332900, Peoples R China. [Gallacher, David] Univ Sydney, Sch Life & Environm Sci, Narrabri, NSW 2390, Australia. RP Zhou, SX (通讯作者)，Chinese Acad Sci, Lushan Bot Garden, Jiujiang 332900, Peoples R China. EM zhousx@lsbg.cn TC 0 Z9 0 PD OCT PY 2021 VL 13 IS 10 BP 1054 EP 1070 DI 10.1007/s40333-021-0020-6 UT WOS:000727300300006 DA 2023-03-23 ER PT J AU Sun, L Liu, YF Wang, XT Liu, Y Wu, GL AF Sun, Lei Liu, Yi-Fan Wang, Xiangtao Liu, Yu Wu, Gao-Lin TI Soil nutrient loss by gully erosion on sloping alpine steppe in the northern Qinghai-Tibetan Plateau SO CATENA DT Article AB Global warming and grazing activities have exacerbated soil erosion in alpine steppe. Gully erosion is a great threat to land degradation in alpine steppe ecosystem. Yet, little is known about the in-situ effects of gully erosion on soil properties at cross section and lengthwise position in alpine steppe ecosystem on the Qinghai-Tibetan Plateau. Here, we used a paired sampling method to compare the soil properties of two erosion gullies (shallow gully and deep gully) at cross section and lengthwise position. The results showed that gully erosion generally induced serious soil nutrient loss and differed between shallow gully and deep gully. However, available phosphorus variation (Delta AP) showed an increase both in shallow gully (from -0.86% to 17.17%) and deep gully (from 8.00% to 45.60%), and pH variation (Delta pH) showed an increase (from -3.40% to 9.01%) in the deep gully. Soil sand content and soil nutrient properties were more sensitive to gully erosion in different cross sections than that in different lengthwise positions, which indicated that the depth of erosion gullies largely determining soil nutrients loss in erosion gullies. Therefore, it is necessary to pay more attention to the ecological restoration of deep erosion gullies to control soil loss and reduce the loss of soil nutrients. These results may conducive to offer a theoretical guidance to achieve the combined goal of gully erosion regulation of alpine steppe ecosystem on the Qinghai-Tibetan Plateau. C1 [Sun, Lei; Wang, Xiangtao; Wu, Gao-Lin] Tibet Agr & Anim Husb Univ, Anim Sci Coll, Nyingchi 860000, Peoples R China. [Liu, Yi-Fan; Liu, Yu; Wu, Gao-Lin] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Liu, Yi-Fan; Liu, Yu; Wu, Gao-Lin] Chinese Acad Sci & Minist Water Resource, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. [Wu, Gao-Lin] CAS Ctr Excellence Quaternary Sci & Global Change, Xian 710061, Peoples R China. RP Wu, GL (通讯作者)，Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. EM wugaolin@nwsuaf.edu.cn TC 5 Z9 5 PD JAN PY 2022 VL 208 AR 105763 DI 10.1016/j.catena.2021.105763 EA SEP 2021 UT WOS:000708436100009 DA 2023-03-23 ER PT J AU Qi, XE Wang, C He, TJ Ding, F Zhang, XF An, LZ Xu, SJ AF Qi, Xing-e Wang, Chen He, Tianjiao Ding, Fan Zhang, Xinfang An, Lizhe Xu, Shijian TI Bacterial community changes and their responses to nitrogen addition among different alpine grassland types at the eastern edge of Qinghai-Tibetan Plateau SO ARCHIVES OF MICROBIOLOGY DT Article AB Soil microbes play a fundamental role in maintaining nutrient biogeochemical cycles. To understand the distribution of soil bacterial communities on grassland plateaus, high-throughput sequencing was used to compare bacterial communities in soils from swamp meadows (SM), alpine meadows (AM), alpine steppes (AS), and desert steppes (DS) at the eastern edge of the Qinghai-Tibetan Plateau (QTP) in China. We then compared response to nitrogen addition between SM and DS soils in microcosms. Bacterial alpha-diversity decreased from SM > AM > AS > DS. Variations in soil properties across grassland types was associated with different soil bacterial communities corresponding to bacterial species associated with nutrient cycles to those associated with degradation. Soil moisture, pH, and total phosphorus were the main drivers of these differences. Nitrogen addition decreased bacterial diversity but had inconsistent effects on soil bacterial communities in SM and DS, which may also indicate that different alpine grassland soil types have unique bacterial communities. Alpine grassland degradation significantly affects bacterial communities, and the response to nitrogen addition depends on the alpine grassland type. These results allow for better predictions of soil bacteria community-level responses to geochemical and environmental change in alpine areas. C1 [Qi, Xing-e; Wang, Chen; He, Tianjiao; Ding, Fan; Zhang, Xinfang; An, Lizhe; Xu, Shijian] Lanzhou Univ, Sch Life Sci, 222 Southern Tianshui Rd, Lanzhou 730000, Peoples R China. RP Zhang, XF (通讯作者)，Lanzhou Univ, Sch Life Sci, 222 Southern Tianshui Rd, Lanzhou 730000, Peoples R China. EM zhangxinfang@lzu.edu.cn TC 2 Z9 2 PD DEC PY 2021 VL 203 IS 10 BP 5963 EP 5974 DI 10.1007/s00203-021-02535-9 EA SEP 2021 UT WOS:000698576300001 DA 2023-03-23 ER PT J AU Zhao, DS Zhu, Y Wu, SH Lu, Q AF Zhao, Dongsheng Zhu, Yu Wu, Shaohong Lu, Qing TI Simulated response of soil organic carbon density to climate change in the Northern Tibet permafrost region SO GEODERMA DT Article AB Climate warming can enhance the decomposition of soil organic matter (SOM), thereby increasing the rate of carbon release from soils. In permafrost regions, climate warming alters the nature of freeze-thaw cycles by affecting sub-surface hydrology and soil temperature, thereby impacting the decomposition of SOM. However, this process is rarely considered in projections of the long-term dynamics of soil organic carbon (SOC) on the Tibetan Plateau (TP) in response to climate change. Here, we employ the CENTURY-FTC model, which implements a freeze-thaw module in the CENTURY model, to simulate the response of top soil organic carbon density (SOCD) at 0-20 cm depth to climate change in the permafrost region of Northern Tibet. Our findings suggest that (i) the average SOCD was 2.123 kg C m(-2) in 2015; (ii) the SOCD decreased at an average rate of 0.7 x 10(-3) kg C m(-2) year(-1) for the period 1961-2015; and (iii) SOCD decreases spatially from south to north across Northern Tibet. Under various climate scenarios, the SOCD is projected to decrease significantly throughout Northern Tibet from 2016 to 2050, with the decline being most pronounced under the representative concentration-pathway (RCP) 8.5 scenario, which projects an increase in global mean surface temperature of 4.5 degrees C by 2100. Superimposed on this pattern, regional differences might be driven by vegetation type, with the largest decrements occurring in southern, alpine-meadow-dominated areas and the smallest in the northern alpine desert. We propose that this declining trend will be enhanced as climate warming continues and might be amplified by the increase in freeze-thaw processes. The addition of a freeze-thaw module to the CENTURY model changes projections of SOCD change due to climate. Whereas the freeze-thaw cycle has had little impact during the baseline period, its influence is likely to increase as climate warming continues. By 2050, freeze-thaw processes are projected to contribute 3% to SOCD decline under the RCP2.6 scenario, which projects a rise in global mean surface temperature of 1.5 degrees C by 2100, and as much as 10% under the RCP8.5 scenario. In general, future warming is likely to result in declining SOCD throughout Northern Tibet and a reduction in the capacity of alpine soils to sequester carbon. C1 [Zhao, Dongsheng; Zhu, Yu; Wu, Shaohong] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, 11 A,Datun Rd, Beijing 100101, Peoples R China. [Zhu, Yu; Wu, Shaohong] Univ Chinese Acad Sci, 19A,Yuquan Rd, Beijing 100049, Peoples R China. [Lu, Qing] East China Univ Technol, Res Ctr Resource & Environm Strategies, Sch Geomat, 418 Guanglan Rd, Nanchang 330013, Jiangxi, Peoples R China. [Lu, Qing] NASG, Key Lab Watershed Ecol & Geog Environm Monitoring, Nanchang 330013, Jiangxi, Peoples R China. RP Zhao, DS (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, 11 A,Datun Rd, Beijing 100101, Peoples R China. EM zhaods@igsnrr.ac.cn TC 3 Z9 3 PD JAN 1 PY 2022 VL 405 AR 115455 DI 10.1016/j.geoderma.2021.115455 EA SEP 2021 UT WOS:000703712100038 DA 2023-03-23 ER PT J AU Dai, LC Fu, RY Guo, XW Ke, X Du, YG Zhang, FW Cao, GM AF Dai, Licong Fu, Ruiyu Guo, Xiaowei Ke, Xun Du, Yangong Zhang, Fawei Cao, Guangmin TI Effect of grazing management strategies on alpine grassland on the northeastern Qinghai-Tibet Plateau SO ECOLOGICAL ENGINEERING DT Article AB In recent decades, alpine grassland has been seriously degraded owing to overgrazing across the Qinghai Tibetan Plateau (QTP), although grazing exclusion has been widely adopted to restore degraded QTP grassland. It remains unknown whether such management approach is effective for all degraded alpine grasslands, and the effect of different grazing management strategies on grassland at varying levels of degradation needs to be assessed. In this study, plots with three grazing management treatments (free grazing, FG; reduced grazing, RG; grazing exclusion, GE) and four degradation stages (non-degradation, ND; light degradation, LD; moderate degradation, MD; heavy degradation, HD) were compared. Our results showed that the total aboveground biomass (AGB) and species richness (SR) under free grazing treatment were reduced with increasing degradation, whereas total belowground biomass (BGB) under free grazing treatment increased with increasing degradation. Furthermore, the responses of SR, AGB and BGB to grazing management varied with the degree of degradation. The total AGB in the LD, MD and HD stages increased significantly following RG and GE treatments, but there was no significant change of AGB in the ND stage. Meanwhile, SR reduced significantly following RG and GE treatments under all degradation stages except for HD. After RG and GE treatments, the total BGB increased significantly in the ND stage but decreased significantly under GE treatment in the MD and HD stages. Furthermore, the responses of plant functional groups to grazing management were varied. The Gramineae AGB increased significantly across all degradation levels under RG and GE treatments, whereas the sedges AGB decreased (except in the MD stage under GE management). Our results suggested that the effect of grazing management on alpine grassland depended on the degree of degradation. C1 [Dai, Licong] Hainan Univ, Coll Ecol & Environm, Haikou 570228, Hainan, Peoples R China. [Dai, Licong; Guo, Xiaowei; Ke, Xun; Du, Yangong; Zhang, Fawei; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810001, Peoples R China. [Fu, Ruiyu] Nanning Normal Univ, Sch Geog & Planning, Nanning 530001, Peoples R China. RP Guo, XW; Cao, GM (通讯作者)，Xinning Rd 23, Xining 810008, Peoples R China. EM guoxw@nwipb.cas.cn; caogm@nwipb.cas.cn TC 7 Z9 7 PD DEC PY 2021 VL 173 AR 106418 DI 10.1016/j.ecoleng.2021.106418 EA SEP 2021 UT WOS:000704979200005 DA 2023-03-23 ER PT J AU Liu, YY Ren, HY Zheng, C Zhou, RL Hu, TM Yang, PZ Zhang, W Wang, ZQ Li, Y Zhang, ZY Wen, ZM AF Liu, Yangyang Ren, Hanyu Zheng, Cheng Zhou, Ronglei Hu, Tianming Yang, Peizhi Zhang, Wei Wang, Zhenqian Li, Yan Zhang, Zhaoying Wen, Zhongming TI Untangling the effects of management measures, climate and land use cover change on grassland dynamics in the Qinghai-Tibet Plateau, China SO LAND DEGRADATION & DEVELOPMENT DT Article AB Multiple large-scale ecological conservation programmes have been launched by the Chinese Government to combat grassland degradation across the Qinghai-Tibet Plateau (QTP) since 1999. However, the mechanisms by which these ecological initiatives might affect grassland changes remains unknown. Here, we examined the land use cover change (LUCC) and net primary productivity (NPP) of the grassland in the QTP in 2001-2016. The effects of LUCC, management measures, and climate variation on grassland NPP were quantitatively evaluated. The grassland area had a net increase of 96,397 km(2), which could be attributed to the conversion of desert and forests. The total NPP of grassland increased by 154,073.7 GgC center dot yr(-1) in 2001-2016, of which the contribution of climate and human factors occupied 35.58% and 64.42%, respectively. Specifically, climate variation caused an overall increase of 54,823.24 GgC center dot yr(-1)in grassland total NPP. The climate-dominated NPP decrease was widely found in the eastern and southern QTP. The contribution of LUCC and management measures to the increase of grassland NPP was 62.78% and 37.22%, respectively. This increase was mostly found in the mid-east region of the QTP, which could sufficiently counteract the negative effect of climate variation on NPP. Overall, these findings seem to demonstrate that these ecological restoration programs have substantially promote the increase of grassland NPP and contribute to understanding the degree to which the grassland ecosystem may respond to the LUCC and management measures under the ecological restoration projects, which are essential to developing more effective ecological measures for future grassland restoration in the QTP. C1 [Liu, Yangyang; Ren, Hanyu; Zheng, Cheng; Zhou, Ronglei; Hu, Tianming; Yang, Peizhi; Zhang, Wei; Wen, Zhongming] Northwest A&F Univ, Coll Grassland Agr, Yangling 712100, Shaanxi, Peoples R China. [Wang, Zhenqian] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou, Peoples R China. [Li, Yan] Nanjing Forestry Univ, Coll Forestry, Nanjing, Peoples R China. [Zhang, Zhaoying] Nanjing Univ, Int Inst Earth Syst Sci, Jiangsu Prov Key Lab Geog Informat Sci & Technol, Nanjing 210023, Peoples R China. RP Wen, ZM (通讯作者)，Northwest A&F Univ, Coll Grassland Agr, Yangling 712100, Shaanxi, Peoples R China.; Zhang, ZY (通讯作者)，Nanjing Univ, Int Inst Earth Syst Sci, Jiangsu Prov Key Lab Geog Informat Sci & Technol, Nanjing 210023, Peoples R China. EM zhaoying_zhang@163.com; zmwen@ms.iswc.ac.cn TC 7 Z9 7 PD NOV PY 2021 VL 32 IS 17 BP 4974 EP 4987 DI 10.1002/ldr.4084 EA SEP 2021 UT WOS:000695942900001 DA 2023-03-23 ER PT J AU Qiu, J Ma, C Jia, YH Wang, JZ Cao, SK Li, FF AF Qiu, Jun Ma, Cang Jia, Ying-Hui Wang, Jin-Zhao Cao, Shou-Kai Li, Fang-Fang TI The distribution and behavioral characteristics of plateau pikas (Ochotona curzoniae) SO ZOOKEYS DT Article AB Plateau pikas (Ochotona curzoniae) are regarded as one of the main causes of the degradation of alpine meadows in the Qinghai-Tibet Plateau (QTP). The population density of plateau pikas is directly related to the degree of grassland damage. In this study, field observation was conducted for one week in the southeastern QTP in August 2019. A random encounter model (REM) was used to estimate the population density of plateau pikas from photographs and videos, and the frequencies of different behaviors were calculated. In addition, the effects of water-source distance and terrain on the distribution of plateau pikas and the frequencies of different pika behaviors under different population densities were explored. The observations and knowledge derived from this study provide a reference for the population control of plateau pikas. C1 [Qiu, Jun; Li, Fang-Fang] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Qiu, Jun] Tsinghua Univ, State Key Lab Hydrosci & Engn, Beijing 100084, Peoples R China. [Ma, Cang; Wang, Jin-Zhao; Cao, Shou-Kai] Qinghai Univ, Sch Water Resources & Elect Power, Xining 810016, Peoples R China. [Jia, Ying-Hui; Li, Fang-Fang] China Agr Univ, Coll Water Resources & Civil Engn, Beijing 100083, Peoples R China. RP Li, FF (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China.; Li, FF (通讯作者)，China Agr Univ, Coll Water Resources & Civil Engn, Beijing 100083, Peoples R China. EM liff@cau.edu.cn TC 2 Z9 2 PD SEP 14 PY 2021 IS 1059 BP 157 EP 171 DI 10.3897/zookeys.1059.63581 UT WOS:000704694000001 DA 2023-03-23 ER PT J AU Ade, L Millner, JP Hou, FJ AF Ade, Luji Millner, James P. Hou, Fujiang TI The dominance of Ligularia spp. related to significant changes in soil microenvironment SO ECOLOGICAL INDICATORS DT Article AB Exploring how plants adapt to and change the surrounding environment has become essential to understanding their survival strategies and co-evolution mechanisms. Ligularia virgaurea and Ligularia sagitta are the two most common species in the alpine grazing ecosystems of the eastern Qinghai-Tibetan Plateau (QTP) and becoming increasingly dominant. Studies have suggested that overgrazing has allowed Ligularia to gain a competitive advantage by changing plant community structure, which is often closely related to the soil environment. However, we don't fully understand the soil environment changes during this process, and the underlying mechanisms have not been explored. Therefore, we investigated plant community characteristics, soil fertility and soil microbial diversity in the L. virgaurea and L. sagitta communities on the eastern QTP. Ligularia spp. significantly changed the plant community by reducing biomass, vegetation coverage, abundance, and biodiversity, and the effect of L. sagitta on the plant community was stronger than that of L. virgaurea. In the plant communities dominated by L. virgaurea and L. sagitta, soil nutrients and soil microbial communities changed significantly. Aggregated boosted trees analysis revealed that soil Mg levels had the greatest relative influence on the structure and diversity of the soil microbial community. Our study provides data and a theoretical basis for revealing the survival strategies of L. sagitta and L. virgaurea and, provides a basis for weed management in grazed ecosystems. C1 [Ade, Luji; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Minist Agr,State Key Lab Grassland Argo Ecosyst, Lanzhou 730020, Peoples R China. [Millner, James P.] Massey Univ, Palmerston North 4474, New Zealand. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Minist Agr,State Key Lab Grassland Argo Ecosyst, Lanzhou 730020, Peoples R China. EM adlj19@lzu.edu.cn; J.P.Millner@massey.ac.nz; cyhoufj@lzu.edu.cn TC 2 Z9 3 PD NOV PY 2021 VL 131 AR 108183 DI 10.1016/j.ecolind.2021.108183 EA SEP 2021 UT WOS:000703312400006 DA 2023-03-23 ER PT J AU Liu, YC Li, Z Chen, YN AF Liu, Yongchang Li, Zhi Chen, Yaning TI Continuous warming shift greening towards browning in the Southeast and Northwest High Mountain Asia SO SCIENTIFIC REPORTS DT Article AB Remote sensing and ground vegetation observation data show that climate warming promotes global vegetation greening, and the increase in air temperature in High Mountain Asia (HMA) is more than twice the global average. Under such a drastic warming in climate, how have the vegetation dynamics in HMA changed? In this study, we use the Normalized Difference Vegetation Index (NDVI) from 1982 to 2015 to evaluate the latest changes in vegetation dynamics in HMA and their climate-driving mechanisms. The results show that over the past 30 years, HMA has generally followed a "warm-wet" trend, with temperatures charting a continuous rise. During 1982-1998 precipitation increased (1.16 mm yr(-1)), but depicted to reverse since 1998 (- 2.73 mm yr(-1)). Meanwhile, the NDVI in HMA increased (0.012 per decade) prior to 1998, after which the trend reversed and declined (- 0.005 per decade). The main reason for the browning of HMA vegetation is the dual effects of warming and precipitation changes. As mentioned, the increase in air temperature in HMA exceeds the global average. The increase of water vapor pressure deficit caused by global warming accelerates the loss and consumption of surface water, and also aggravates the soil water deficit. That is to say, the abnormal increase of land evapotranspiration far exceeds the precipitation, and the regional water shortage increases. Climate change is the primary factor driving these vegetation and water dynamics, with the largest proportion reaching 41.9%. C1 [Liu, Yongchang; Li, Zhi; Chen, Yaning] Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China. [Liu, Yongchang; Li, Zhi; Chen, Yaning] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Li, Z; Chen, YN (通讯作者)，Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China.; Li, Z; Chen, YN (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM liz@ms.xjb.ac.cn; chenyn@ms.xjb.ac.cn TC 9 Z9 9 PD SEP 9 PY 2021 VL 11 IS 1 AR 17920 DI 10.1038/s41598-021-97240-4 UT WOS:000695272000052 DA 2023-03-23 ER PT J AU Tang, R Zhao, YT Lin, HL AF Tang, Rong Zhao, Yuting Lin, Huilong TI Spatio-Temporal Variation Characteristics of Aboveground Biomass in the Headwater of the Yellow River Based on Machine Learning SO REMOTE SENSING DT Article AB Accurate estimation of the aboveground biomass (AGB) of grassland is a key link in understanding the regional carbon cycle. We used 501 aboveground measurements, 29 environmental variables, and machine learning algorithms to construct and verify a custom model of grassland biomass in the Headwater of the Yellow River (HYR) and selected the random forest model to analyze the temporal and spatial distribution characteristics and dynamic trends of the biomass in the HYR from 2001 to 2020. The research results show that: (1) the random forest model is superior to the other three models (R-val(2) = 0.56, RMSEval = 51.3 g/m(2)); (2) the aboveground biomass in the HYR decreases spatially from southeast to northwest, and the annual average value and total values are 176.8 g/m(2) and 20.73 Tg, respectively; (3) 69.51% of the area has shown an increasing trend and 30.14% of the area showed a downward trend, mainly concentrated in the southeast of Hongyuan County, the northeast of Aba County, and the north of Qumalai County. The research results can provide accurate spatial data and scientific basis for the protection of grassland resources in the HYR. C1 [Tang, Rong; Zhao, Yuting; Lin, Huilong] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Tang, Rong; Zhao, Yuting; Lin, Huilong] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730000, Peoples R China. RP Lin, HL (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China.; Lin, HL (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730000, Peoples R China. EM tangr19@lzu.edu.cn; zhaoyt14@lzu.edu.cn; linhuilong@lzu.edu.cn TC 8 Z9 9 PD SEP PY 2021 VL 13 IS 17 AR 3404 DI 10.3390/rs13173404 UT WOS:000694620800001 DA 2023-03-23 ER PT J AU Tang, ZS Jiang, YM Hua, R Zhou, JW Chu, B Ye, GH Hua, LM Tian, YL AF Tang, Zhuangsheng Jiang, Yongmei Hua, Rui Zhou, Jianwei Chu, Bin Ye, Guohui Hua, Limin Tian, Yongliang TI Study on Greenhouse Gas Emissions from the Mounds Produced by Plateau Zokor (Eospalax Baileyi) on Qinghai-Tibet Plateau SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB Plateau zokor (Eospalax baileyi) is a native subterranean rodent living in alpine rangeland on the Qinghai-Tibet Plateau. The zokors excavate soil in their tunnels and push it out to form the zokor mound, which is secondary bare land on the ground. In the alpine rangeland ecosystem, the bare lands emit greenhouse gases and reduce carbon sequestration. However, little is known about the greenhouse gas emissions from the zokor mounds with bare soil. In this study, we used a gas analyzer in situ combined with a closed static chamber to monitor the emissions of CO2 and CH4 from new mounds, seminew mounds, old mounds, and the pasture without mounds. The biomass bacteria, fungi, and actinomycetes in the 0- to 20-cm soil layer of the mounds and the pasture without mounds were simultaneously investigated. To explore the source of the CO2 and CH4 emissions, we compared the differences of CO2 and CH4 flux in the zokors' active tunnels, tunnel-free soil, and mound-free pasture. The results showed that 1) the highest flux of CO2 and CH4 emissions in the same month was from new mounds, followed by seminew mounds, old mounds, and the pasture without mounds; 2) CO2 and CH4 emissions from the different mounds in 4 mo were significantly influenced by months and mound types, although there was no significant interaction between these factors; and 3) the flux of CO2 and CH4 emissions from the zokor mounds were significantly positively correlated with their total biomass of microbes and the flux of CO2 and CH4 inside the zokor active tunnels. The CO2 and CH4 inside the zokor active tunnels had more contributions to CO2 and CH4 emissions from the zokor mounds than the soil microbes' biomass in the mounds. (C) 2021 The Society for Range Management. Published by Elsevier Inc. All rights reserved. C1 [Tang, Zhuangsheng; Hua, Rui; Zhou, Jianwei; Chu, Bin; Ye, Guohui; Hua, Limin] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst,Natl Forestry & Grassla, Minist Educ,Engn & Technol Res Ctr Alpine Rodent, Lanzhou 730070, Peoples R China. [Jiang, Yongmei] Sichuan Univ Arts & Sci, Dept Chem & Chem Engn, Dazhou 635000, Peoples R China. [Tian, Yongliang] Forage & Fodder Workstn Dazhou, Dazhou 635000, Peoples R China. RP Hua, LM; Tian, YL (通讯作者)，1 Yingmen Village, Lanzhou 730070, Gansu, Peoples R China. EM hualm@gsau.edu.cn; TYLtianyongliang@yeah.net TC 0 Z9 1 PD SEP PY 2021 VL 78 BP 36 EP 45 DI 10.1016/j.rama.2021.05.002 UT WOS:000752373800005 DA 2023-03-23 ER PT J AU Yuan, Q Yuan, QZ Ren, P AF Yuan Qin Yuan Quanzhi Ren Ping TI Coupled effect of climate change and human activities on the restoration/degradation of the Qinghai-Tibet Plateau grassland SO JOURNAL OF GEOGRAPHICAL SCIENCES DT Article AB Climate change (CC) and human activities (HA) are the main reasons for the restoration/degradation of the Qinghai-Tibet Plateau (QTP) grassland. Many related studies have been conducted thus far, but the impact mechanism of CC coupled with HA on QTP remains unclear. We summarized the two main coupling factors in recent years (specifically, in the past five years) and obtained the following conclusions. (1) CC and HA have positive and negative effects on the QTP grassland ecosystem. CC primarily affects grassland ecology through temperature, humidification, and extreme climate, and HA mainly affects ecosystems through primary, secondary, and tertiary industries and restoration measures. (2) CC coupled with HA affects soil, plants, animals, and fungi/microbes. CC makes the snow line rise by increasing the temperature, which expands the zone for HA. CC also restricts HA through hydrological changes, extreme climate, and outbreak of pikas and pests. Simultaneously, measures are implemented through HA to control and adapt to CC. Hence, the grassland ecosystem is comprehensively influenced by CC and HA. (3) The grassland ecosystem dynamically adapts to the disturbance caused by CC and HA by changing its physiological characteristics, distribution range, diet structure, community structure, and physical state. Simultaneously, it responds to environmental changes through desertification, poisonous weeds, rodent outbreak, release of harmful gases, and other means. This work can be used as a reference for the sustainable development of the QTP grassland. C1 [Yuan Qin; Yuan Quanzhi; Ren Ping] Sichuan Normal Univ, Inst Geog & Resources Sci, Chengdu 610101, Peoples R China. [Yuan Qin; Yuan Quanzhi] Sichuan Normal Univ, Sustainable Dev Res Ctr Resources & Environm West, Chengdu 610066, Peoples R China. [Ren Ping] Sichuan Normal Univ, Key Lab Land Resources Evaluat & Monitoring South, Minist Educ, Chengdu 610066, Peoples R China. RP Yuan, QZ (通讯作者)，Sichuan Normal Univ, Inst Geog & Resources Sci, Chengdu 610101, Peoples R China.; Yuan, QZ (通讯作者)，Sichuan Normal Univ, Sustainable Dev Res Ctr Resources & Environm West, Chengdu 610066, Peoples R China. EM yq190098829@163.com; yuanqz@sicnu.edu.cn TC 12 Z9 13 PD SEP PY 2021 VL 31 IS 9 BP 1299 EP 1327 DI 10.1007/s11442-021-1899-8 UT WOS:000692383300004 DA 2023-03-23 ER PT J AU Li, M Yu, HL Meng, BP Sun, Y Zhang, JG Zhang, HF Wu, JS Yi, SH AF Li, Meng Yu, Huilin Meng, Baoping Sun, Yi Zhang, Jianguo Zhang, Huifang Wu, Jianshuang Yi, Shuhua TI Drought reduces the effectiveness of ecological projects: Perspectives from the inter-annual variability of vegetation index SO ECOLOGICAL INDICATORS DT Article AB To alleviate grassland degradation and improve ecosystem functions, the Chinese government has implemented some ecological projects since 2004 across the Tibetan Plateau, such as 'Return Grazing Land to Grassland Project' and the 'Compensation and Rewards to Herders for Natural Grassland Conservation'. Meanwhile, the frequency and intensity of drought events have strengthened in this plateau. However, how grasslands respond to these projects and drought remains controversial. Here, taking the northern Tibetan Plateau (NTP) as the study area, we first quantified the spatiotemporal changes in the annual maximum grassland NDVI (NDVImax) after the implementation of the ecological projects (2005-2015). Then, we assessed the effects of drought (Standardized Precipitation-Evapotranspiration Index, SPEI) and ecological projects on the dynamics of NDVImax. The results showed that (1) the grazing intensity decreased significantly across the NTP after the start of ecological projects, but grassland NDVImax did not increase as expected. Statistically, 53.7% of grasslands showed a decreasing NDVImax, of which 5.7% had a significant decrease (P < 0.05), mainly in the central and eastern NTP. (2) NDVImax positively correlated with SPEI at the pixel, county, and regional scales, suggesting that drought was the driving force for the decreasing NDVImax. The severe and extreme drought events in 2015 contributed to 9.4% and 17.7% reduction of grassland NDVImax, respectively. (3) The residual analysis demonstrated that there were 4.4% of the grasslands experienced human-induced degradation. However, on the whole, the effects of ecological projects on vegetation changes of the NTP were positive. Our findings suggested that the positive effects of the ecological projects on vegetation growth were relatively mitigated or offset by drought. Thus, we question the validity of evaluating the effectiveness of ecological projects only according to the trend of vegetation productivity derived from remote-sensing based vegetation index. C1 [Li, Meng; Yu, Huilin; Meng, Baoping; Sun, Yi; Zhang, Jianguo; Zhang, Huifang; Yi, Shuhua] Nantong Univ, Sch Geog Sci, Nantong 226007, Peoples R China. [Wu, Jianshuang] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. RP Yi, SH (通讯作者)，Nantong Univ, Sch Geog Sci, Inst Fragile Ecosyst & Environm, 999 Tongjing Rd, Nantong 226007, Peoples R China.; Wu, JS (通讯作者)，Chinese Acad Agr Sci CAAS, Inst Environm & Sustainable Dev Agr, Zhongguancun South Str 12, Beijing 100081, Peoples R China. EM wujianshuang@caas.cn; yis@ntu.edu.cn TC 5 Z9 5 PD NOV PY 2021 VL 130 AR 108158 DI 10.1016/j.ecolind.2021.108158 EA AUG 2021 UT WOS:000692520000004 DA 2023-03-23 ER PT J AU Zhou, TC Sun, J Zong, N Hou, G Shi, PL AF Zhou, Tiancai Sun, Jian Zong, Ning Hou, Ge Shi, Peili TI Community species diversity mediates the trade-off between aboveground and belowground biomass for grasses and forbs in degraded alpine meadow, Tibetan Plateau SO ECOLOGY AND EVOLUTION DT Article AB Although many empirical experiments have shown that increasing degradation results in lower aboveground biomass (AGB), our knowledge of the magnitude of belowground biomass (BGB) for individual plants is a prerequisite for accurately revealing the biomass trade-off in degraded grasslands. Here, by linking the AGB and BGB of individual plants, species in the community, and soil properties, we explored the biomass partitioning patterns in different plant functional groups (grasses of Stipa capillacea and forbs of Anaphalis xylorhiza). Our results indicated that 81% and 60% of the biomass trade-off variations could be explained by environmental factors affecting grasses and forbs, respectively. The change in community species diversity dominated the biomass trade-off via either direct or indirect effects on soil properties and biomass. However, the community species diversity imparted divergent effects on the biomass trade-off for grasses (scored at -0.72) and forbs (scored at 0.59). Our findings suggest that plant communities have evolved two contrasting strategies of biomass allocation patterns in degraded grasslands. These are the "conservative" strategy in grasses, in which plants with larger BGB trade-off depends on gigantic roots for soil resources, and the "opportunistic" strategy in forbs, in which plants can adapt to degraded lands using high variation and optimal biomass allocation. C1 [Zhou, Tiancai; Zong, Ning; Hou, Ge; Shi, Peili] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing, Peoples R China. [Zhou, Tiancai; Hou, Ge; Shi, Peili] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Sun, Jian] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A,Datun Rd, Beijing 100101, Peoples R China. EM shipl@igsnrr.ac.cn TC 1 Z9 1 PD OCT PY 2021 VL 11 IS 19 BP 13259 EP 13267 DI 10.1002/ece3.8048 EA AUG 2021 UT WOS:000690791100001 DA 2023-03-23 ER PT J AU Quan, XL Qiao, YM Chen, MC Duan, ZH Shi, HL AF Quan, Xiaolong Qiao, Youming Chen, Mengci Duan, Zhonghua Shi, Huilan TI Comprehensive evaluation of the allelopathic potential of Elymus nutans SO ECOLOGY AND EVOLUTION DT Article AB Elymus nutans has been widely planted together with other perennial grasses for rebuilding degraded alpine meadow atop the Qinghai-Tibetan Plateau. However, the rebuilt sown pastures begin to decline a few years after establishing. One of the possible causes for the degradation of sown grassland may come from allelopathy of planted grasses. The purpose of this study was to examine allelopathic potential of Elymus nutans. Three types of aqueous extract from Elymus nutans and its root zone soil were prepared, and 5 highland crops and 5 perennial grasses were used as recipient plants. Elymus nutans exhibited strong allelopathic potential on germination and seedling growth of 5 crops, but different crops or perennial grasses respond to the extract differently. The pieces aqueous extract have stronger inhibition than whole plant extract and root zone soil extract. Hordeum vulgar var. nudum, Avena sativa, and Festuca sinensis were the most affected, while Chenopodium quinoa and Elymus sibiricus were the least affected. Elymus nutans presented less influence on Poa pratensis and Poa crymophylla than on Festuca sinensis. It is recommended that the species combination of mixture for restoration should be considered for allopathic effects on the coseeding to decrease the seeding rate ratio of Elymus nutans. The annual dicot crop seeds of Chenopodium quinoa and Brassica napus can be used as alternative subsequent crop for the seed field of Elymus nutans monoculture. C1 [Quan, Xiaolong; Qiao, Youming; Chen, Mengci; Duan, Zhonghua] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Shi, Huilan] Qinghai Univ, Coll Ecol Environm Engn, Xining, Peoples R China. RP Qiao, YM (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. EM ymqiao@aliyun.com TC 3 Z9 4 PD SEP PY 2021 VL 11 IS 18 BP 12389 EP 12400 DI 10.1002/ece3.7982 EA AUG 2021 UT WOS:000687870500001 DA 2023-03-23 ER PT J AU Wang, XM Han, C Lan, BR Wang, C Zhu, GB AF Wang, Xiaomin Han, Chang Lan, Bangrui Wang, Cheng Zhu, Guibing TI Antibiotic resistance genes on the Qinghai-Tibet Plateau above an elevation of 5,000 m SO ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH DT Article AB Antibiotic resistance genes (ARGs) widely occur in both anthropogenic and remote environments. Several studies have investigated the distribution of antibiotic resistance in natural environments. However, the occurrence and diversity of ARGs in remote environments at high elevations have not yet been well elucidated. Abundance, diversity, as well as influencing factors of ARGs in different ecosystems on the Qinghai-Tibet Plateau beyond elevation 5,000 m were explored, using high-throughput quantitative PCR. Totally, 197 ARGs and 12 mobile genetic elements (MGEs) were determined with abundances ranging from 3.75 x 10(6) to 2.39 x 10(7) and from 2.21 x 10(4) to 1.62 x 10(6) copies g(-1), respectively. Both the absolute and relative abundances of ARGs in farmland were lower than those in wetland and grassland. The diversity and dominant resistance mechanism of ARG profiles showed obvious differences among these ecosystems. Bacterial communities and MGEs significantly correlated with ARG profiles, while physico-chemical factors showed little impact. The high abundance and strong positive correlation between integron intI-1 and ARGs suggested a high potential horizontal ARG transfer. Based on the results, the Qinghai-Tibet Plateau can be regarded as a considerable ARG gene pool. This study provides insights into the provenance of ARGs at high elevations. C1 [Wang, Xiaomin; Han, Chang; Lan, Bangrui; Zhu, Guibing] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, Key Lab Drinking Water Sci & Technol, Beijing 100085, Peoples R China. [Wang, Xiaomin; Lan, Bangrui; Zhu, Guibing] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Cheng] Sun Yat Sen Univ, Southern Marine Sci & Engn Guangdong Lab Zhuhai, South China Sea Inst, Guangzhou 510006, Peoples R China. RP Zhu, GB (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, Key Lab Drinking Water Sci & Technol, Beijing 100085, Peoples R China.; Zhu, GB (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM gbzhu@rcees.ac.cn TC 3 Z9 2 PD JAN PY 2022 VL 29 IS 3 BP 4508 EP 4518 DI 10.1007/s11356-021-16007-6 EA AUG 2021 UT WOS:000686447400005 DA 2023-03-23 ER PT J AU Zhou, TC Hou, G Sun, J Zong, N Shi, PL AF Zhou, Tiancai Hou, Ge Sun, Jian Zong, Ning Shi, Peili TI Degradation shifts plant communities from S- to R-strategy in an alpine meadow, Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The replacement of dominant sedges/grasses with secondary forbs is common in alpine rangelands, but the un-derlying plant ecological strategies and their relevance to leaf traits and their variabilities of different plant func-tional groups remain largely unknown. Here, we measured key leaf traits and analyzed the competitor, stress-tolerator and ruderal (CSR) strategies of major species with different functional groups (sedges, grasses and forbs) in an alpine meadow along a degradation gradient on the Tibetan Plateau. Our results indicated that S-selected species were dominant in both non-degraded (C:S:R = 1:95:4%) and severely degraded (C:S:R = 2:87:11%) meadows. However, there was a shift from S-to R-strategy in the communities after rangeland degra-dation. More specifically, sedges and grasses with a "conservative" strategy maintained stronger S-strategy to tol-erate degraded and stressful conditions. In contrast, forbs with an "opportunistic" strategy (increase 9.5% in R-score) tended to adapt to degraded stages. Moreover, 51.1% and 23.9% of the increased R-scores in forbs were accounted by leaf mass per area and specific leaf area, respectively. Generally, higher leaf water and nitrogen con-tents coupled with larger variations in leaf traits and flexible SR strategies in forbs enabled them to capitalize on lower soil water and nutrient availability. Our findings highlighted that the contrasting strategies of plant species in response to the decrease in available resources might lead to niche expansion of secondary forbs and loss of diversity in the degraded alpine meadow. The emerging alternative stable states in the degraded rangelands might bring about a predicament for rangeland restoration. (c) 2021 Published by Elsevier B.V. C1 [Zhou, Tiancai; Hou, Ge; Zong, Ning; Shi, Peili] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Zhou, Tiancai; Hou, Ge; Zong, Ning; Shi, Peili] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. [Sun, Jian] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Resource, Beijing 100101, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. EM zhoutc.18b@igsnrr.ac.cn; sunjian@itpcas.ac.cn; zongning@igsnrr.ac.cn; shipl@igsnrr.ac.cn TC 10 Z9 11 PD DEC 15 PY 2021 VL 800 AR 149572 DI 10.1016/j.scitotenv.2021.149572 EA AUG 2021 UT WOS:000701792800009 DA 2023-03-23 ER PT J AU Li, WY Li, F Zeng, HJ Ma, L Qi, LY Wang, XC Wang, WY Peng, Z Degen, AA Bai, YF Zhang, T Huang, M Han, J Shang, ZH AF Li, Wenyan Li, Fei Zeng, Haijun Ma, Lin Qi, Lingyan Wang, Xiaochun Wang, Wenyin Peng, Zhen Degen, A. Allan Bai, Yanfu Zhang, Tao Huang, Mei Han, Jin Shang, Zhanhuan TI Diversity and Variation of Asymbiotic Nitrogen-Fixing Microorganisms in Alpine Grasslands on the Tibetan Plateau SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Asymbiotic nitrogen-fixing (ANF) bacteria contribute a substantial amount of nitrogen in ecosystems, especially in those with low symbiotic nitrogen fixation (SNF) capability. Degradation of alpine grassland is widespread on the Tibetan Plateau and sown grassland has become one of the main strategies for grassland restoration. However, the diversity and community structure of ANF bacteria in different grassland types remain unknown. The aim of this study was to fill this gap. Soil samples were obtained from 39 grassland plots selected from three counties in the eastern Tibetan Plateau. The plots were classified as natural grassland (NG), sown grassland (SG), lightly degraded grassland (LDG), and severely degraded grassland (SDG). ANF microbial communities of the four grassland types were compared at the level of community and species diversity by 16S rRNA high-throughput sequencing technology. The phylum Proteobacteria accounted for >72% of the ANF bacteria. The community structures of soil ANF bacteria differed significantly (p < 0.01) among grassland types. We concluded that: (1) planting gramineous forage could possibly mitigate the decrease in diversity of soil ANF bacteria caused by grassland degradation; and (2) the diversity of soil ANF bacteria in alpine grassland of the Tibetan Plateau is closely related to grassland degradation and restoration. C1 [Li, Wenyan; Li, Fei; Zeng, Haijun; Ma, Lin; Qi, Lingyan; Wang, Xiaochun; Wang, Wenyin; Peng, Zhen; Bai, Yanfu; Zhang, Tao; Huang, Mei; Han, Jin; Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. [Degen, A. Allan] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, Beer Sheva, Israel. [Shang, Zhanhuan] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Areas, Xining, Peoples R China. [Shang, Zhanhuan] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Qinghai Prov Key Lab Adapt Management Alpine Gras, Xining, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China.; Shang, ZH (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Areas, Xining, Peoples R China.; Shang, ZH (通讯作者)，Qinghai Univ, Qinghai Acad Anim & Vet Sci, Qinghai Prov Key Lab Adapt Management Alpine Gras, Xining, Peoples R China. EM shangzhh@lzu.edu.cn TC 0 Z9 0 PD AUG 13 PY 2021 VL 9 AR 702848 DI 10.3389/fevo.2021.702848 UT WOS:000692749500001 DA 2023-03-23 ER PT J AU Wang, Y Wang, XF Yin, LC Feng, XM Zhou, CW Han, L Lu, YH AF Wang, Yi Wang, Xiaofeng Yin, Lichang Feng, Xiaoming Zhou, Chaowei Han, Ling Lu, Yihe TI Determination of conservation priority areas in Qinghai Tibet Plateau based on ecosystem services SO ENVIRONMENTAL SCIENCE & POLICY DT Article AB Facing rapid ecological degradation in the Qinghai Tibet Plateau (QTP), the determination of priority areas for conservation (CPAs) based on ecosystem services (ESs) is a key step for nature conservation and sustainable development. However, the trade-off between services makes the plan of maintaining protected areas (PAs) a challenge. In this study, by quantifying a variety of essential ESs in the QTP from 2000 to 2015, we used the multi-criteria ordered weighted average method to balance the trade-offs and determine the key CPAs for ES conservation. We found that the multi-criteria based selection of CPAs leads to higher (1.35) and more balanced ES protection efficiency (PE) than the single strategy. The CPAs obtained based on the logical framework of this paper are mainly located in the southeastern QTP and cover an area of 12.78 % of the QTP (330,124.76 km2). The comprehensive PE of ES was 1.68, and the PE of carbon storage, water yield, soil conservation, and cultural service were 2.20, 2.17, 4.54, and 1.59, respectively. Additionally, compared with the existing PA settings, our results can increase the proportion of biodiversity of amphibians and birds by more than 12 %. The framework of CPAs selection in this paper can provide a reference for the government's growing nature conservation affairs, which will contribute to sustainable development. C1 [Wang, Yi; Wang, Xiaofeng; Han, Ling] Changan Univ, Coll Land Engn, 126 Yanta Rd, Xian 710054, Peoples R China. [Wang, Xiaofeng; Han, Ling] Changan Univ, Key Lab Shaanxi Land Consolidat Project, Xian 710054, Peoples R China. [Yin, Lichang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Feng, Xiaoming; Zhou, Chaowei; Lu, Yihe] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China. RP Wang, XF (通讯作者)，Changan Univ, Coll Land Engn, 126 Yanta Rd, Xian 710054, Peoples R China. EM wangxf@chd.edu.cn TC 10 Z9 10 PD OCT PY 2021 VL 124 BP 553 EP 566 DI 10.1016/j.envsci.2021.07.019 EA AUG 2021 UT WOS:000691599800006 DA 2023-03-23 ER PT J AU Das, A Samanta, GP AF Das, Amartya Samanta, G. P. TI Influence of environmental noises on a prey-predator species with predator-dependent carrying capacity in alpine meadow ecosystem SO MATHEMATICS AND COMPUTERS IN SIMULATION DT Article AB Degradation of carrying capacity due to any reason is a serious concern for ecosystem as well as for dynamical system. It is observed in alpine meadow ecosystem that carrying capacity of vegetation reduces due to digging holes, throwing out soils, piling up mounds by plateau pika. In this ecosystem, it is also observed that height of vegetation increases death rate of plateau pika. These two facts when considered with environmental fluctuation make it an interesting topic of discussion in dynamical system. This motivation leads us to a stochastic analysis of a prey-predator model in alpine meadow ecosystem. In this analysis, Gaussian White noise has been introduced to exhibit the influence of environmental fluctuations on prey's growth rate and predator's death rate. We have established positivity and boundedness of the system theoretically. Extinction scenario, persistence of the system and global attractivity of solutions are also established. Numerical simulation validates theoretical results. Moreover, the appropriateness of the model in numerical simulation has also been justified with the help of some field experimental data. In discussion section, another approach for formulating the model has also been discussed. (C) 2021 International Association for Mathematics and Computers in Simulation (IMACS). Published by Elsevier B.V. All rights reserved. C1 [Das, Amartya; Samanta, G. P.] Indian Inst Engn Sci & Technol, Dept Math, Sibpur 711103, Howrah, India. RP Samanta, GP (通讯作者)，Indian Inst Engn Sci & Technol, Dept Math, Sibpur 711103, Howrah, India. EM amartyadas92@gmail.com; g_p_samanta@yahoo.co.uk TC 2 Z9 2 PD DEC PY 2021 VL 190 BP 1294 EP 1316 DI 10.1016/j.matcom.2021.07.014 EA AUG 2021 UT WOS:000690877900001 DA 2023-03-23 ER PT J AU Sun, J Fu, BJ Zhao, WW Liu, SL Liu, GH Zhou, HK Shao, XQ Chen, YC Zhang, Y Deng, YF AF Sun, Jian Fu, Bojie Zhao, Wenwu Liu, Shiliang Liu, Guohua Zhou, Huakun Shao, Xinqing Chen, Youchao Zhang, Yu Deng, Yanfang TI Optimizing grazing exclusion practices to achieve Goal 15 of the sustainable development goals in the Tibetan Plateau SO SCIENCE BULLETIN DT Editorial Material C1 [Sun, Jian] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Fu, Bojie; Liu, Guohua] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China. [Fu, Bojie; Zhao, Wenwu] Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Liu, Shiliang] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Reg Qinghai, Xining 810008, Peoples R China. [Shao, Xinqing] China Agr Univ, Coll Grassland Sci & Technol, Beijing 100193, Peoples R China. [Chen, Youchao] Chinese Acad Sci, Key Lab Aquat Bot & Watershed Ecol, Wuhan Bot Garden, Wuhan 430074, Peoples R China. [Zhang, Yu; Deng, Yanfang] Qilian Mt Nat Reserve Bur Qinghai Prov, Xining 810008, Peoples R China. RP Fu, BJ (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China.; Fu, BJ (通讯作者)，Beijing Normal Univ, Fac Geog Sci, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. EM bfu@rcees.ac.cn TC 23 Z9 24 PD AUG 15 PY 2021 VL 66 IS 15 BP 1493 EP 1496 DI 10.1016/j.scib.2021.03.014 EA AUG 2021 UT WOS:000684396500004 DA 2023-03-23 ER PT J AU Wang, YC Lu, GX Yu, H Du, XF He, Q Yao, ST Zhao, LR Huang, CX Wen, XC Deng, Y AF Wang, Yingcheng Lu, Guangxin Yu, Hao Du, Xiongfeng He, Qing Yao, Shiting Zhao, Lirong Huang, Caixia Wen, Xiaocheng Deng, Ye TI Meadow degradation increases spatial turnover rates of the fungal community through both niche selection and dispersal limitation SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The alpine meadow ecosystem, as the main ecosystem of the Qinghai-Tibet Plateau, has been heavily degraded over the past several decades due to overgrazing and climate change. Although soil microorganisms play key roles in the stability and succession of grassland ecosystems, their response to grassland degradation has not been investigated at spatial scale. Here, we systematically analyzed the spatial turnover rates of soil prokaryotic and fungal communities in degraded and undegraded meadows through distance-decay relationship (DDR) and species area relationship (SAR), as well as the community assembly mechanisms behind them. Although the composition and structure of both fungal and prokaryotic communities showed significant changes between undegraded and degraded meadows, steeper spatial turnover rates were only observed in fungi (Degraded Alpine Meadow beta = 0.0142, Undegraded Alpine Meadow beta = 0.0077, P < 0.05). Mantel tests indicated that edaphic variables and vegetation factors showed significant correlations to the beta diversity of fungal community only in degraded meadow, suggesting soil and vegetation heterogeneity both contributed to the variation of fungal community in that system. Correspondingly, a novel phylogenetic null model analysis demonstrated that environmental selection was enhanced in the fungal community assembly process during meadow degradation. Interestingly, dispersal limitation was also enhanced for the fungal community in the degraded meadow, and its relative contribution to other assembly process (i.e. selection and drift) showed a significant linear increase with spatial distance, suggesting that dispersal limitation played a greater role as distance increased. Our findings indicated the spatial scaling of the fungal community is altered during meadow degradation by both niche selec-tion and dispersal limitation. This study provides a new perspective for the assessment of soil microbial responses to vegetation changes in alpine areas. (c) 2021 Elsevier B.V. All rights reserved. C1 [Wang, Yingcheng; Lu, Guangxin; Yao, Shiting; Zhao, Lirong; Huang, Caixia; Wen, Xiaocheng] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Wang, Yingcheng; Yu, Hao; Du, Xiongfeng; He, Qing; Deng, Ye] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, CAS Key Lab Environm Biotechnol, Beijing 100085, Peoples R China. [Du, Xiongfeng; He, Qing; Deng, Ye] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. [Yu, Hao] Liaoning Tech Univ, Coll Environm Sci & Engn, Fuxing 123000, Peoples R China. RP Deng, Y (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, CAS Key Lab Environm Biotechnol, Beijing 100085, Peoples R China. EM yedeng@rcees.ac.ar TC 8 Z9 8 PD DEC 1 PY 2021 VL 798 AR 149362 DI 10.1016/j.scitotenv.2021.149362 EA AUG 2021 UT WOS:000701768400007 DA 2023-03-23 ER PT J AU Liu, YY Zhou, RL Ren, HY Zhang, W Zhang, ZX Zhang, ZY Wen, ZM AF Liu, Yangyang Zhou, Ronglei Ren, Hanyu Zhang, Wei Zhang, Zhixin Zhang, Zhaoying Wen, Zhongming TI Evaluating the dynamics of grassland net primary productivity in response to climate change in China SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Net primary productivity (NPP) has been considered as a direct indicator to access the ter-restrial primary production. However, considerable uncertainties remain toward the response mechanism of NPP to climate change across annual and seasonal scales, especially for grassland ecosystems. In this study, the spatiotemporal dynamics of grassland NPP and its prominent climate-controlling factor were evaluated based on the CASA model and groundbased meteorological data across annual and seasonal scales in China from 1982 to 2016. Results showed that the annual mean grassland NPP was 294.58 gC.m(-2).a(-1) over the 35 years; the largest annual mean NPP was observed in Alpine sub-alpine meadow (235.72 +/- 13.21 gC.m(-2).a(-1)), while the smallest annual mean NPP value occurred in Desert grassland (97.27 +/- 9.64 gC.m(-2)a(-1)). Moreover, the multiyear mean grassland NPP showed a decreasing trend from the southeast to the northwest spatially. Temporally, grassland NPP exhibited a significant increasing trend (slope = 2.4 gC.m(-2).a(-1); p < 0.0001) over the whole study period; an abrupt change point across the grassland NPP time series was observed in 1999. Specially, 66.34% of the grassland area showed an increasing trend in NPP, and the areas with a significant increasing trend were concentrated in Qinghai-Tibet Plateau and the northern area of Xinjiang. Further climate factor analysis with NPP indicated that NPP positively correlated with precipitation and negatively correlated with temperature for the whole grassland area. In particular, the temperature was a dominant driver in NPP variations for Alpine sub-alpine meadow, Slope grassland and Alpine sub-alpine grassland, while precipitation controlled the most in NPP variations for Plain grassland and Desert grassland. The accumulation of grassland NPP in spring and autumn benefits from the increase in temperature, and precipitation promoted the accumulated NPP in summer and winter. (C) 2021 The Authors. Published by Elsevier B.V. C1 [Liu, Yangyang; Zhou, Ronglei; Ren, Hanyu; Zhang, Wei; Zhang, Zhixin; Wen, Zhongming] Northwest A&F Univ, Coll Grassland Agr, Xinong Rd 22, Yangling 712100, Shaanxi, Peoples R China. [Liu, Yangyang; Zhang, Zhaoying] Nanjing Univ, Int Inst Earth Syst Sci, Jiangsu Prov Key Lab Geog Informat Sci & Technol, Nanjing 210023, Peoples R China. RP Wen, ZM (通讯作者)，Northwest A&F Univ, Coll Grassland Agr, Xinong Rd 22, Yangling 712100, Shaanxi, Peoples R China.; Zhang, ZY (通讯作者)，Nanjing Univ, Int Inst Earth Syst Sci, Jiangsu Prov Key Lab Geog Informat Sci & Technol, Nanjing 210023, Peoples R China. EM Zhaoying_zhang@163.com; zmwen@ms.iswc.ac.cn TC 13 Z9 14 PD AUG PY 2021 VL 28 AR e01574 DI 10.1016/j.gecco.2021.e01574 UT WOS:000684552100001 DA 2023-03-23 ER PT J AU Zhang, LF Chen, ZG Zhang, X Zhao, L Li, Q Chen, DD Tang, YH Gu, S AF Zhang, Lifeng Chen, Zhiguang Zhang, Xiang Zhao, Liang Li, Qi Chen, Dongdong Tang, Yanhong Gu, Song TI Evapotranspiration and Its Partitioning in Alpine Meadow of Three-River Source Region on the Qinghai-Tibetan Plateau SO WATER DT Article AB The Qinghai-Tibetan Plateau (QTP) is generally considered to be the water source region for its surrounding lowlands. However, there have only been a few studies that have focused on quantifying alpine meadow evapotranspiration (ET) and its partitioning, which are important components of water balance. This paper used the Shuttleworth-Wallace (S-W) model to quantify soil evaporation (E) and plant transpiration (T) in a degraded alpine meadow (34 degrees 24 ' N, 100 degrees 24 ' E, 3963 m a.s.l) located at the QTP from September 2006 to December 2008. The results showed that the annual ET estimated by the S-W model (ETSW) was 511.5 mm (2007) and 499.8 mm (2008), while E estimated by the model (E-SW) was 306.0 mm and 281.7 mm for 2007 and 2008, respectively, which was 49% and 29% higher than plant transpiration (T-SW). Model analysis showed that ET, E, and T were mainly dominated by net radiation (R-n), while leaf area index (LAI) and soil water content at a 5 cm depth (SWC5cm) were the most important factors influencing ET partitioning. The study results suggest that meadow degradation may increase water loss through increasing E, and reduce the water conservation capability of the alpine meadow ecosystem. C1 [Zhang, Lifeng; Chen, Zhiguang; Gu, Song] NanKai Univ, Coll Life Sci, 94 Weijin Rd, Tianjin 300071, Peoples R China. [Zhang, Xiang] Cent South Univ Forestry & Technol, Inst Life Sci & Technol, 498 Shaoshannan Rd, Changsha 410004, Peoples R China. [Zhao, Liang; Li, Qi; Chen, Dongdong] Chinese Acad Sci, Northwest Inst Plateau Biol, 23 Xinning Rd, Xining 810008, Peoples R China. [Tang, Yanhong] Peking Univ, Coll Urban & Environm Sci, 5 Yiheyuan Rd, Beijing 100781, Peoples R China. RP Gu, S (通讯作者)，NanKai Univ, Coll Life Sci, 94 Weijin Rd, Tianjin 300071, Peoples R China. EM 1120170360@mail.nankai.edu.cn; ecomaxchen@gmail.com; t20192478@csuft.edu.cn; lzhao@nwipb.cas.cn; liqi@nwipb.cas.cn; chendd@nwipb.cas.cn; tangyh@pku.edu.cn; songgu@nankai.edu.cn TC 0 Z9 0 PD AUG PY 2021 VL 13 IS 15 AR 2061 DI 10.3390/w13152061 UT WOS:000682252500001 DA 2023-03-23 ER PT J AU Liu, WL Jiang, YL Wang, GX Su, Y Smoak, JM Liu, MY Duan, BL AF Liu, Weilong Jiang, Yonglei Wang, Genxu Su, Yan Smoak, Joseph M. Liu, Meiyu Duan, Baoli TI Effects of N addition and clipping on above and belowground plant biomass, soil microbial community structure, and function in an alpine meadow on the Qinghai-Tibetan Plateau SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB Nitrogen (N) enrichment and grazing are two factors that have profound effects on grassland ecosystem processes and functions. This study evaluated separate and combined effects of clipping and N addition on soil properties, soil microbial community structure, and soil extracellular enzyme activity within our experiment design which included three clipping intensities (i.e., unclipped, moderate, and heavy clipping) and two different N treatments (with and without N addition) in an alpine meadow ecosystem on the Qinghai-Tibetan Plateau, China. Results revealed that N addition alone did not significantly affect total soil organic carbon (TOC), total soil N (TN), dissolved organic carbon (DOC), microbial biomass carbon (MBC), and N (MBN) after 3 years of treatments. The moderate clipping alone increased root exudation rates whereas the heavy clipping decreased root exudation rates, TOC, TN, DOC, MBC and MBN, fungi biomass, and the ratio of fungi to bacteria. The effects of N addition were generally neutral or negative in the heavy clipping treatment. In contrast, N addition significantly increased aboveground biomass, MBC, MBN, DOC, and soil water content but decreased inorganic N in the moderate clipping. RDA analysis showed that N addition could stimulate soil microbial community structure in the moderate clipping treatment by impacting the availability of labile soil C. Our results improve the understanding of the role of N addition in regulating soil C storage among different grazing intensities in alpine meadows. C1 [Liu, Weilong; Su, Yan; Liu, Meiyu; Duan, Baoli] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Jiang, Yonglei] Yunnan Acad Tobacco Agr Sci, Kunming 650021, Yunnan, Peoples R China. [Wang, Genxu] Sichuan Univ, Coll Water Resource & Hydropower, State Key Lab Hydraul & Mt River Engn, Chengdu 610065, Peoples R China. [Smoak, Joseph M.] Univ S Florida, Sch Geosci, St Petersburg, FL 33701 USA. RP Wang, GX (通讯作者)，Sichuan Univ, Coll Water Resource & Hydropower, State Key Lab Hydraul & Mt River Engn, Chengdu 610065, Peoples R China.; Duan, BL (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. EM wanggx@scu.edu.cn; duanbl@imde.ac.cn TC 4 Z9 4 PD SEP-OCT PY 2021 VL 106 AR 103344 DI 10.1016/j.ejsobi.2021.103344 EA JUL 2021 UT WOS:000695236600008 DA 2023-03-23 ER PT J AU Wang, JL Li, W Cao, WX Abalori, TA Liu, YZ Xin, YQ Wang, SL Zhang, DG AF Wang, Jinlan Li, Wen Cao, Wenxia Abalori, Theophilus Atio Liu, Yuzhen Xin, Yuqiong Wang, Shilin Zhang, Degang TI Soil bacterial community responses to short-term grazing exclusion in a degraded alpine shrubland-grassland ecotone SO ECOLOGICAL INDICATORS DT Article AB Grazing exclusion by fencing is a common and effective grassland management strategy for degraded grassland restoration. Soil bacteria, the most important decomposers of soil organic matter, is the linkage between plant and soil. However, soil bacterial alpha-diversity and community composition in the recover process of degraded shrubland - grassland ecotone on the Qinghai-Tibet Plateau has not been well understood. Thus, in this research, lightly and heavily degraded shrubland - grassland ecotone and its adjacent communities (alpine shrubland and alpine meadow) during recover process on the Qinghai-Tibet Plateau were selected to study alpha-diversity and community composition of soil bacteria, as well as the relationships among soil bacterial community, plant community and soil properties. Our results demonstrated that: 1) Dominant taxa at the phylum and genera level in all samples were similar. Proteobacteria, Acidobacteria and Bacteroidetes were dominant phyla, RB41, H16 and Ferruginibacter were dominant genera. 2) Grazing exclusion had no effect on soil bacterial alpha-diversity. However, grazing exclusion significantly decreased relative abundance of the Chloroflexi phylum, but grazing exclusion significantly increased the Elusimicrobia phylum relative abundance in the alpine meadow plot. 3) There were no significant differences on soil bacterial alpha-diversity between the heavily and lightly degraded grassland. However, relative abundance of the Planctomycetes phylum, Deltaproteobacteria class and RB41 genus in the alpine meadow plot of heavily degraded grassland were significantly lower than those in the lightly degraded grassland. 4) The higher plant community alpha-diversity and soil nutrition of shrubland - grassland ecotone did not result in a higher soil bacterial alpha-diversity. However, relative abundances of Chloroflexi phylum, Deltaproteobacteria class and Nitrospira class in the shrubland - grassland ecotone were significantly higher than those in the alpine meadow and alpine shrubland plots inside fence of the lightly degraded grassland. 5) Structural equation model (SEM) showed that soil organic carbon and soil total nitrogen were dominant factors affecting soil bacterial alpha-diversity. 6) Redundancy analysis (RDA) indicated that soil nitrate nitrogen and soil total nitrogen were the main driving factors for soil bacterial community composition. Our research found that the changes of soil bacterial alpha-diversity is incongruous with plant community alpha-diversity, while soil bacterial community composition is paralleled with plant community alpha-diversity and soil characteristics, especially the soil chemical property. These findings can provide management support for the restoration of degraded alpine shrubland. C1 [Wang, Jinlan; Cao, Wenxia; Abalori, Theophilus Atio; Xin, Yuqiong; Wang, Shilin; Zhang, Degang] Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Grassland Ecosyst Key Lab, Grassland Sci Coll,Minist Educ, Lanzhou 730070, Peoples R China. [Li, Wen; Liu, Yuzhen] Qinghai Univ, Qinghai Acad Anim Sci & Vet Med, Key Lab Dev Forage Germplasm Qinghai Tibetan Plat, Xining 810003, Peoples R China. RP Cao, WX (通讯作者)，Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Grassland Ecosyst Key Lab, Grassland Sci Coll,Minist Educ, Lanzhou 730070, Peoples R China. EM caowenxia@foxmail.com TC 3 Z9 3 PD NOV PY 2021 VL 130 AR 108043 DI 10.1016/j.ecolind.2021.108043 EA JUL 2021 UT WOS:000692256500002 DA 2023-03-23 ER PT J AU Li, HL Li, TT Sun, WJ Zhang, W Zhang, Q Yu, LJ Qin, ZC Guo, B Liu, J Zha, XC AF Li, Hailing Li, Tingting Sun, Wenjuan Zhang, Wen Zhang, Qing Yu, Lijun Qin, Zhangcai Guo, Bin Liu, Jia Zha, Xingchu TI Degradation of wetlands on the Qinghai-Tibetan Plateau causing a loss in soil organic carbon in 1966-2016 SO PLANT AND SOIL DT Article AB Aims Reveal the soil organic carbon (SOC) stock change in the Qinghai-Tibetan Plateau (QTP) alpine wetlands in the past fifty years. The Qinghai-Tibetan Plateau (QTP) has a large area of alpine marshland and wet meadows. Artificial drainage, overgrazing and climate change have caused severe degradation of the alpine wetlands. However, little is known about the effects of wetland degradation on SOC stock, and studies only focused on the Zoige marshland, the biggest marshland of China. Direct SOC observations from the extensively distributed wet meadows remain scarce. Methods SOC in the soil surface layer (0-50 cm) were investigated at four wetland sites where degradation has continued for decades. One site is in marshland, and three are in wet meadows of the QTP. Using datasets from the literature and the field measurements of the present study, we estimated the loss of alpine wetland SOC. Results and conclusions Initially, marshland degradation to wet meadows prompted the accumulation of SOC; however, grazing in wet meadows reduced SOC accumulation. Wetland degradation to dried meadows led to a much greater SOC loss than that in the initial degradation stage, and grazing exacerbated the loss of SOC. An exponential decay rate of SOC was found in the grazed dried meadows. The wetlands of the QTP, have lost 141 +/- 25 Tg in 1966-2016, representing 15% of the SOC stock. C1 [Li, Hailing; Li, Tingting; Zhang, Wen; Zhang, Qing; Yu, Lijun] Chinese Acad Sci, Inst Atmospher Phys, LAPC, Beijing 100029, Peoples R China. [Li, Hailing; Sun, Wenjuan; Zhang, Wen] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Li, Tingting; Qin, Zhangcai] Southern Marine Sci & Engn Guangdong Lab Zhuhai, Zhuhai 519000, Peoples R China. [Sun, Wenjuan] Chinese Acad Sci, Inst Bot, LVEC, Beijing 100093, Peoples R China. [Sun, Wenjuan] Chinese Acad Sci, Inst Bot, Beijing 100093, Peoples R China. [Zhang, Wen] Chinese Acad Sci, Inst Atmospher Phys, Beijing 100029, Peoples R China. [Qin, Zhangcai] Sun Yat Sen Univ, Sch Atmospher Sci, Guangzhou 510245, Peoples R China. [Guo, Bin] Heavy Rain & Drought Flood Disasters Plateau & Ba, Chengdu 610072, Peoples R China. [Guo, Bin] Aba Prefecture Meteorol Stn, Maerkang 624000, Peoples R China. [Liu, Jia] Sichuan Climate Ctr, Chengdu 610071, Peoples R China. [Zha, Xingchu] Meteorol Bur Ruoergai, Ruoergai 624500, Peoples R China. RP Zhang, W (通讯作者)，Chinese Acad Sci, Inst Atmospher Phys, LAPC, Beijing 100029, Peoples R China.; Sun, WJ; Zhang, W (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China.; Sun, WJ (通讯作者)，Chinese Acad Sci, Inst Bot, LVEC, Beijing 100093, Peoples R China.; Sun, WJ (通讯作者)，Chinese Acad Sci, Inst Bot, Beijing 100093, Peoples R China.; Zhang, W (通讯作者)，Chinese Acad Sci, Inst Atmospher Phys, Beijing 100029, Peoples R China. EM sunwj@ibcas.ac.cn; zhw@mail.iap.ac.cn TC 6 Z9 6 PD OCT PY 2021 VL 467 IS 1-2 BP 253 EP 265 DI 10.1007/s11104-021-05086-6 EA JUL 2021 UT WOS:000677252900001 DA 2023-03-23 ER PT J AU You, Y Ren, JF Wu, J Ma, ZW Gu, YC Wang, YX Wang, ZF Bowatte, S Zhou, QP Hou, FJ AF You, Yang Ren, Jingfei Wu, Jing Ma, Zhouwen Gu, Yongchao Wang, Yingxin Wang, Zhaofeng Bowatte, Saman Zhou, Qingping Hou, Fujiang TI Forage taste agents modifying yak grazing decrease soil microbial diversity in alpine meadow SO APPLIED SOIL ECOLOGY DT Article AB Taste is a crucial sense of livestock for their selective feeding. As feed additives, taste agents such as salty and sweet agents are often added to livestock supplementary feed to increase feed intake, and bitter agents are commonly used as repellents to protect vegetation from browsing animals. Selective feeding of grazing livestock affects community structure and ecosystem function in natural grasslands. Regulating livestock feed intake by applying taste agents to pasture is a novel grazing management tool. However, the effects of these taste agents on the soil microbial community following selective feeding have so far not been fully evaluated. In this study, three different taste agents, Denatonium benzoate (bitter agent), NaCl (salty agent), and Sodium cyclamate (sweet agent), were sprayed onto alpine meadow pasture on the Qinghai-Tibet Plateau. Resulting evidence indicates that spray-application of taste agents to alpine pasture over three consecutive growing seasons, indirectly modifies soil bacterial diversity by stimulating appetite, and encouraging more selective feeding of pasture species. Compared with control, treatment with the salty agent increased both yak dry matter intake, and soil bulk density, but decreased plant diversity. Yet, increased forage uptake was accompanied by alterations to soil nutrient availability and bacterial community structure, including lower soil available nitrogen and bacterial a-diversity. Soil bulk density, NO3--N, soil moisture, aboveground biomass, and quantity of yak dung, were the main forces driving changes to soil bacterial diversity. Moreover, the structural equation model showed that applying taste agents to pasture affects soil bacterial diversity directly, and indirectly. This study further highlights that pastoral application of taste agents has impacts on the soil bacterial community, supporting the necessity to include bacterial components in evaluation of the consequences of using taste agents as a grazing management tool. C1 [You, Yang; Ren, Jingfei; Wu, Jing; Ma, Zhouwen; Gu, Yongchao; Wang, Yingxin; Wang, Zhaofeng; Bowatte, Saman; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat,Minist Ag, Lanzhou 730020, Peoples R China. [Zhou, Qingping] Southwest Univ Nationalities, Inst Qinghai Tibet Plateau, Chengdu 610041, Peoples R China. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat,Minist Ag, Lanzhou 730020, Peoples R China. EM cyhoufj@lzu.edu.cn TC 2 Z9 2 PD DEC PY 2021 VL 168 AR 104160 DI 10.1016/j.apsoil.2021.104160 EA JUL 2021 UT WOS:000701814300008 DA 2023-03-23 ER PT J AU Hu, L Zi, HB Luo, XP Lerdau, M Wang, CT AF Hu, Lei Zi, Hongbiao Luo, Xueping Lerdau, Manuel Wang, Changting TI Root dynamics along a restoration chronosequence of revegetated grasslands in degraded alpine meadows of the Qinghai-Tibetan Plateau, China SO LAND DEGRADATION & DEVELOPMENT DT Article AB Revegetation using perennial grass, such as Elymus nutans is an effective approach in abating grassland degradation on the Qinghai-Tibetan Plateau. However, knowledge of root dynamics along restoration chronosequences of revegetated grasslands are limited. To gain better insight into root dynamics, we used minirhizotrons to examine changes in root traits, including root standing crop, production, mortality, and turnover along a restoration chronosequence of three revegetated grasslands (cultivated in 2002, 2006, and 2010 corresponding to late, middle, and early recovery stage) in four consecutive growing seasons (2014, 2015, 2016, and 2017). We found that the aboveground plant biomass was higher in the middle recovery stage than that in the early and late recovery stages, while plant species richness showed an increasing trend from the early to late recovery stage. Similar with the plant biomass response, the belowground root standing crop and production were significantly higher in the middle recovery stage than in the early and late recovery stages. Root mortality was decreased and root turnover tend to be stable from the early to late recovery stage. Root turnover was positively correlated with soil NO3--N content and negatively correlated with aboveground plant biomass. Moreover, root standing crop and mortality increased from May to September across all growing seasons; however, root production decreased within this period. Our study highlighted significant links between aboveground and belowground plant parts that may help effectively manage revegetated grassland on the Qinghai-Tibetan Plateau. C1 [Hu, Lei; Zi, Hongbiao; Luo, Xueping; Wang, Changting] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau Res, Chengdu 610041, Peoples R China. [Lerdau, Manuel] Univ Virginia, Dept Environm Sci, Charlottesville, VA USA. RP Wang, CT (通讯作者)，Southwest Minzu Univ, Inst Qinghai Tibetan Plateau Res, Chengdu 610041, Peoples R China. EM hl007873@163.com; wangct@swun.edu.cn TC 0 Z9 0 PD AUG 15 PY 2021 VL 32 IS 13 BP 3561 EP 3572 DI 10.1002/ldr.3954 EA JUL 2021 UT WOS:000674036000001 DA 2023-03-23 ER PT J AU Zhang, ZC Liu, Y Sun, J Wu, GL AF Zhang, Zhenchao Liu, Yu Sun, Jian Wu, Gao-Lin TI Suitable duration of grazing exclusion for restoration of a degraded alpine meadow on the eastern Qinghai-Tibetan Plateau SO CATENA DT Article AB Grazing exclusion (GE) is a key national ecological restoration project widely applied to rehabilitate degraded grasslands. To date, there have been many debates on the effectiveness of GE for grassland recovery, and it is still poorly understood how degraded alpine meadows in the semi-humid area with relative rich rainfall in the Qinghai-Tibetan Plateau respond to GE with different durations. We selected a chronosequence of grazing-excluded alpine meadows to examine the dynamics of grassland functions. The results showed that the dominant functional group shifted from forbs to graminoids after 8 to 10 years GE and then returned to forbs. The plant population density increased significantly with GE time (P < 0.01). The total biomass, species richness, Shannon diversity index, and relative importance value of graminoids first increased and then decreased with increasing plant population density, whereas the relative importance value of forbs presented the opposite trend. All turning points were between 1350 and 1650 plants per m(2) which occurred from 8 to 10 years of GE. As the duration of GE increased, the ecosystem multifunctionality first dramatically increased and then became steady after 8 to 10 years of GE. These findings imply that GE is of great practical significance to prevent degradation in semi-humid regions of the Qinghai-Tibetan Plateau, where we recommend that GE should cease after approximately 8 to 10 years to restore degraded alpine meadows from the perspective of plant productivity, diversity, community structure, and ecosystem multifunctionality. C1 [Zhang, Zhenchao; Liu, Yu; Wu, Gao-Lin] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Zhang, Zhenchao; Sun, Jian] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Sci LATP, Beijing 100101, Peoples R China. [Liu, Yu; Wu, Gao-Lin] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Area, Xining 810008, Peoples R China. [Liu, Yu; Wu, Gao-Lin] Qinghai Univ, Qinghai Acad Anim & Vet Sci, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Sci LATP, Beijing 100101, Peoples R China. EM zhenchaozhang0626@163.com; kingliuyu@nwafu.edu.cn; sunjian@iptcas.ac.cn; wugaolin@nwsuaf.edu.cn TC 10 Z9 10 PD DEC PY 2021 VL 207 AR 105582 DI 10.1016/j.catena.2021.105582 EA JUL 2021 UT WOS:000703268900007 DA 2023-03-23 ER PT J AU Chen, N Song, CC Xu, XF Wang, XW Cong, N Jiang, PP Zu, JX Sun, L Song, YY Zuo, YJ Liu, JZ Zhang, T Xu, MJ Jiang, P Wang, ZP Huang, K AF Chen, Ning Song, Changchun Xu, Xiaofeng Wang, Xianwei Cong, Nan Jiang, Peipei Zu, Jiaxing Sun, Li Song, Yanyu Zuo, Yunjiang Liu, Jianzhao Zhang, Tao Xu, Mingjie Jiang, Peng Wang, Zhipeng Huang, Ke TI Divergent impacts of atmospheric water demand on gross primary productivity in three typical ecosystems in China SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Atmospheric water demand is practically characterized as vapor pressure deficit (VPD) and has been identified as a critical driver of ecosystem function, by affecting plant mortality, wildfires, and carbon loss. In this study, we used daily eddy covariance data across Chinese forest, grassland and shrubland ecosystems, in combination with remote sensing data, to investigate the impacts of VPD on gross primary productivity (GPP). We found divergent VPD impacts on GPP among grassland, shrubland and forest ecosystems. The VPD yielded substantial inhibitory impacts on GPP in grassland ecosystems and this suppressing impact was regulated by soil water content (SWC), showing that GPP declined with VPD under dry conditions but increased with VPD under wet conditions. This GPP variance was attributed to VPD, SWC and their interactions. More than 50% of the variability in GPP was explained by SWC in grassland ecosystems and by VPD in forest and shrubland ecosystems. Partial correlation analysis, random forest, and multiple linear regression revealed similar results when temperature, radiation and SWC were considered. Compared with shrubland and forest ecosystems, grassland has drier environmental conditions and poorer soil water-holding capacity that led to lower SWC and stronger negative impacts on VPD. Thus, GPP was susceptible to the negative impacts of higher VPD, especially under dryness stress. Our results highlight the need to comprehensively consider divergent VPD impacts for different ecosystems to more accurately assess climate impacts on ecosystem function. C1 [Chen, Ning; Song, Changchun; Wang, Xianwei; Sun, Li; Song, Yanyu; Zuo, Yunjiang; Liu, Jianzhao] Chinese Acad Sci, Northeast Inst Geog & Agroecol, Key Lab Wetland Ecol & Environm, Changchun 130102, Peoples R China. [Song, Changchun] Dalian Univ Technol, Sch Hydraul Engn, Dalian 116024, Peoples R China. [Cong, Nan; Wang, Zhipeng; Huang, Ke] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Xu, Xiaofeng] San Diego State Univ, Biol Dept, Ecol Modeling & Integrat Lab, San Diego, CA 92182 USA. [Jiang, Peipei] Shandong Normal Univ, Coll Life Sci, Key Lab Plant Stress Res, Jinan 250014, Peoples R China. [Zu, Jiaxing] Nanning Normal Univ, Minist Educ, Key Lab Environm Change & Resources Use Beibu Gul, Nanning 530001, Peoples R China. [Zhang, Tao; Xu, Mingjie] Shenyang Agr Univ, Coll Agron, Shenyang 110866, Peoples R China. [Jiang, Peng] China Meteorol Adm, Inst Liaoning Meteorol, Shenyang 110166, Peoples R China. RP Song, CC (通讯作者)，Chinese Acad Sci, Northeast Inst Geog & Agroecol, Key Lab Wetland Ecol & Environm, Changchun 130102, Peoples R China.; Song, CC (通讯作者)，Dalian Univ Technol, Sch Hydraul Engn, Dalian 116024, Peoples R China. EM songcc@iga.ac.cn TC 15 Z9 15 PD SEP 15 PY 2021 VL 307 AR 108527 DI 10.1016/j.agrformet.2021.108527 EA JUL 2021 UT WOS:000682515100037 DA 2023-03-23 ER PT J AU Li, M Zhang, XZ Wu, JS Ding, QN Niu, B He, YT AF Li, Meng Zhang, Xianzhou Wu, Jianshuang Ding, Qiannan Niu, Ben He, Yongtao TI Declining human activity intensity on alpine grasslands of the Tibetan Plateau SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Climate change and human activities have profoundly changed the structure and functioning of alpine grassland ecosystems on the Tibetan Plateau, the most critical ecological safety shelter for Asia. However, it remains unclear to what degree human activity intensity has impacted the alpine grasslands of the Tibetan Plateau. Here we quantify human activity intensity on alpine grasslands of the Tibetan Plateau based on the relationship between actual and potential net primary production. We found that human activity intensity decreased by 16.1% from 2000 to 2017 across the alpine grasslands, which might be driven by recent ecological conservation policies, especially reductions in livestock numbers. Critical thresholds, which show marked grassland responses to different levels of human disturbances, were identified for each ecozone. The net primary production of dry grasslands on the western ecozones was more resistant to human disturbances but with lower resilience than other alpine grasslands on the plateau. Our findings are beneficial to design practical countermeasures to adapt to climate change and recover damaged grasslands on Tibetan Plateau. C1 [Li, Meng; Zhang, Xianzhou; Niu, Ben; He, Yongtao] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, Beijing 100101, Peoples R China. [Li, Meng; Ding, Qiannan] Nantong Univ, Sch Geog Sci, Nantong 226007, Peoples R China. [Wu, Jianshuang] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Wu, Jianshuang] Free Univ Berlin, Inst Biol, Theoret Ecol, D-14195 Berlin, Germany. RP Zhang, XZ (通讯作者)，A11 Datun Rd, Beijing, Peoples R China. EM zhangxz@igsnrr.ac.cn TC 25 Z9 27 PD OCT 15 PY 2021 VL 296 AR 113198 DI 10.1016/j.jenvman.2021.113198 EA JUL 2021 UT WOS:000685353600004 DA 2023-03-23 ER PT J AU Chen, Y Zhang, YJ Chen, N Cong, N Zhu, JT Zhao, G Zu, JX Liu, YJ Zhu, YX Zheng, ZT Shen, RN Zhang, Y Huang, K Tang, Z AF Chen, Yao Zhang, Yangjian Chen, Ning Cong, Nan Zhu, Juntao Zhao, Guang Zu, Jiaxing Liu, Yaojie Zhu, Yixuan Zheng, Zhoutao Shen, Ruonan Zhang, Yu Huang, Ke Tang, Ze TI Nitrogen availability and precipitation variability regulated CO2 fertilization effects on carbon fluxes in an alpine grassland SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB It's generally believed that elevated CO2 (eCO(2)) could stimulate plant growth and the ecosystem carbon (C) sink. However, great uncertainties exist in terms of the CO2 fertilization effect (CFE) magnitude, and how it is regulated by other global change factors. The lack of experimental evidence from the Alpine Region also limits our cognition on the CFE. By conducting a five-year manipulative field experiment in a semi-arid grassland of the Tibetan Plateau, we are aimed to explore the behavior of ecosystem C exchange in response to eCO(2) and N availability under contrasting natural precipitation regimes. The experiment showed that eCO(2) stimulated both gross ecosystem productivity (GEP) and ecosystem respiration (ER), and resulted in a neutral effect on net ecosystem productivity (NEP). The reduction of leaf N concentration under eCO(2) constrained the eCO(2) effects on C fluxes, especially on GEP and NEP. As N addition replenishes N availability in soil and leaf, GEP benefited more from the N addition than the ER. The eCO(2) strengthened the C sink when exogenous N was added simultaneously. Furthermore, precipitation variability played an importance role in mediating the eCO(2) effect among growing seasons. The eCO(2) effects on C fluxes tended to decline with increased water availability. The CFE was suppressed with excessive precipitation when the water-use efficiency (WUE) response was weak and eCO(2)-induced water-saving disappeared. The negative impact of precipitation on the CFE may also be attributed to the short precipitation intervals and insufficient radiation caused by high-frequency precipitation. Our study demonstrates that eCO(2) only stimulates net C uptake under conditions of N addition or during drier periods. Given the widespread N limitation, the efficacy of terrestrial ecosystems in mitigating climate change under rising CO2 may be weaker than projected and is closely related to the precipitation variability. C1 [Chen, Yao; Zhang, Yangjian; Cong, Nan; Zhu, Juntao; Zhao, Guang; Zhu, Yixuan; Zheng, Zhoutao; Shen, Ruonan; Zhang, Yu; Huang, Ke; Tang, Ze] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Chen, Yao; Zhu, Yixuan; Shen, Ruonan; Zhang, Yu; Tang, Ze] Univ Chinese Acad Sci, Beijing 100190, Peoples R China. [Zhang, Yangjian] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhang, Yangjian] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. [Chen, Ning] Chinese Acad Sci, Northeast Inst Geog & Agroecol, Key Lab Wetland Ecol & Environm, Changchun 130102, Peoples R China. [Zu, Jiaxing] Nanning Normal Univ, Minist Educ, Key Lab Environm Change & Resources Use Beibu Gul, Nanning 530001, Peoples R China. [Zu, Jiaxing] Nanning Normal Univ, Guangxi Key Lab Earth Surface Proc & Intelligent, Nanning 530001, Peoples R China. [Liu, Yaojie] Nanjing Univ, Int Inst Earth Syst Sci, Nanjing 210093, Peoples R China. RP Zhang, YJ; Zhao, G (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11 Datun Rd, Beijing 100101, Peoples R China. EM zhangyj@igsnrr.ac.cn; zhaoguang@igsnrr.ac.cn TC 5 Z9 5 PD SEP 15 PY 2021 VL 307 AR 108524 DI 10.1016/j.agrformet.2021.108524 EA JUL 2021 UT WOS:000682515100038 DA 2023-03-23 ER PT J AU Meng, BP Yang, ZG Yu, HY Qin, Y Sun, Y Zhang, JG Chen, JJ Wang, ZW Zhang, W Li, M Lv, YY Yi, SH AF Meng, Baoping Yang, Zhigui Yu, Hongyan Qin, Yu Sun, Yi Zhang, Jianguo Chen, Jianjun Wang, Zhiwei Zhang, Wei Li, Meng Lv, Yanyan Yi, Shuhua TI Mapping of Kobresia pygmaea Community Based on Umanned Aerial Vehicle Technology and Gaofen Remote Sensing Data in Alpine Meadow Grassland: A Case Study in Eastern of Qinghai-Tibetan Plateau SO REMOTE SENSING DT Article AB The Kobresia pygmaea (KP) community is a key succession stage of alpine meadow degradation on the Qinghai-Tibet Plateau (QTP). However, most of the grassland classification and mapping studies have been performed at the grassland type level. The spatial distribution and impact factors of KP on the QTP are still unclear. In this study, field measurements of the grassland vegetation community in the eastern part of the QTP (Counties of Zeku, Henan and Maqu) from 2015 to 2019 were acquired using unmanned aerial vehicle (UAV) technology. The machine learning algorithms for grassland vegetation community classification were constructed by combining Gaofen satellite images and topographic indices. Then, the spatial distribution of KP community was mapped. The results showed that: (1) For all field observed sites, the alpine meadow vegetation communities demonstrated a considerable spatial heterogeneity. The traditional classification methods can hardly distinguish those communities due to the high similarity of their spectral characteristics. (2) The random forest method based on the combination of satellite vegetation indices, texture feature and topographic indices exhibited the best performance in three counties, with overall accuracy and Kappa coefficient ranged from 74.06% to 83.92% and 0.65 to 0.80, respectively. (3) As a whole, the area of KP community reached 1434.07 km(2), and accounted for 7.20% of the study area. We concluded that the combination of satellite remote sensing, UAV surveying and machine learning can be used for KP classification and mapping at community level. C1 [Meng, Baoping; Yang, Zhigui; Sun, Yi; Zhang, Jianguo; Li, Meng; Lv, Yanyan; Yi, Shuhua] Nantong Univ, Inst Fragile Ecoenvironm, Nantong 226007, Peoples R China. [Meng, Baoping; Yang, Zhigui; Sun, Yi; Zhang, Jianguo; Li, Meng; Lv, Yanyan; Yi, Shuhua] Nantong Univ, Sch Geog Sci, Nantong 226007, Peoples R China. [Yu, Hongyan] Qinghai Serv & Guarantee Ctr Qilian Mt Natl Pk, Xining 810001, Peoples R China. [Qin, Yu; Zhang, Wei] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, 320 Donggang West Rd, Lanzhou 730000, Peoples R China. [Chen, Jianjun] Guilin Univ Technol, Coll Geomat & Geoinformat, 12 Jiangan Rd, Guilin 541004, Peoples R China. [Wang, Zhiwei] Guizhou Acad Agr Sci, Guizhou Inst Prataculture, Guiyang 550006, Peoples R China. RP Yi, SH (通讯作者)，Nantong Univ, Inst Fragile Ecoenvironm, Nantong 226007, Peoples R China.; Yi, SH (通讯作者)，Nantong Univ, Sch Geog Sci, Nantong 226007, Peoples R China. EM mengbp09@lzu.edu.cn; 1822021025@stmail.ntu.edu.cn; 18909718038@189.cn; qiny@lzb.ac.cn; sunyi@ntu.edu.cn; sezjg@ntu.edu.cn; chenjj@lzb.ac.cn; wzw1206@lzb.ac.cn; zhangwei2015@lzb.ac.cn; limeng@ntu.edu.cn; lvyy09@lzu.edu.cn; yis@ntu.edu.cn TC 11 Z9 12 PD JUL PY 2021 VL 13 IS 13 AR 2483 DI 10.3390/rs13132483 UT WOS:000671163200001 DA 2023-03-23 ER PT J AU Zhang, Y Gao, QZ Ganjurjav, H Dong, SK Zheng, QZ Ma, YD Liang, KM AF Zhang, Yong Gao, Qingzhu Ganjurjav, Hasbagan Dong, Shikui Zheng, Qiuzhu Ma, Yandan Liang, Kemin TI Grazing Exclusion Changed the Complexity and Keystone Species of Alpine Meadows on the Qinghai-Tibetan Plateau SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Grazing exclusion is an effective approach to restore degraded grasslands. However, the effects of grazing exclusion on keystone species and the complexity of plant community were poorly investigated. Here, we conducted a field survey among different grazing exclusion durations, i.e., Grazing, grazing exclusion below 5 years, grazing exclusion with 5 years, grazing exclusion with 7 years, and grazing exclusion over 7 years, in alpine meadows on the central Qinghai-Tibetan Plateau (QTP). The complexity and keystone species of alpine meadows were analyzed by a network analysis. The results showed the following: (1) The species richness did not change, but aboveground biomass and the coverage of the plant community tended to increase with the extension of the grazing exclusion duration. (2) The soil nutrients, i.e., total nitrogen, total organic carbon, available nitrogen, and available potassium, remained stable, while the soil bulk density decreased under grazing exclusion conditions. (3) There was a hump-shaped change of the complexity (i.e., average connectivity and average clustering coefficient) of the plant community along with the extension of the grazing exclusion duration. Moreover, the keystone species were different among the grazing exclusion treatments. Based on the complexity of the plant community and the changes of keystone species, the optimum duration of grazing exclusion for alpine meadows should be between 5 and 7 years. Our results suggest that besides the productivity, the change of the complexity and keystone species of plant community should be considered when grazing exclusion is adopted to restore the degraded alpine meadows. C1 [Zhang, Yong; Dong, Shikui] Beijing Forestry Univ, Sch Grassland Sci, Beijing, Peoples R China. [Zhang, Yong; Zheng, Qiuzhu; Ma, Yandan; Liang, Kemin] Southwest Forestry Univ, Natl Plateau Wetlands Res Ctr, Coll Wetlands, Kunming, Yunnan, Peoples R China. [Gao, Qingzhu; Ganjurjav, Hasbagan] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. RP Ganjurjav, H (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. EM ganjurjav@foxmail.com TC 4 Z9 6 PD JUN 28 PY 2021 VL 9 AR 638157 DI 10.3389/fevo.2021.638157 UT WOS:000671834400001 DA 2023-03-23 ER PT J AU Yang, C Sun, J AF Yang, Chao Sun, Juan TI Impact of soil degradation on plant communities in an overgrazed Tibetan alpine meadow SO JOURNAL OF ARID ENVIRONMENTS DT Article AB Predicting the impact of overgrazing on soil properties, and thus on plant succession, in the Qinghai-Tibet Plateau (QTP) is one of the primary technical bottlenecks in alpine meadow conservation. Four degradation intensities, namely D1: light degradation, D2: moderate degradation, D3: high degradation, and a non-degraded site as the control (CK), were identified. The soil properties and plant community data were analyzed. With the increase in degradation intensity, the soil pH, conductivity (EC), and bulk density (BD) values significantly increased, while the soil water content, total carbon, total nitrogen, and C/N ratio significantly decreased (p < 0.05). Plant aboveground biomass and Shannon diversity significantly decreased with the increase in degradation intensity (p < 0.05). The dominant species changed from Poa pratensis (CK) to Potentilla multifida (D1), to Iris lactea (D2), and finally to Achnatherum splendens (D3). Overgrazing can lead to changes in soil properties, and changes in soil pH and BD are the primary factors that control the changes in plant community structure and composition with grassland degradation. Soil degradation is conducive to the growth of individual species such as A. splendens, which are associated with a reduction in plant diversity in an alpine meadow of the northeastern QTP. Future research should pay more attention to the key species and soil properties in degraded grasslands. C1 [Yang, Chao; Sun, Juan] Qingdao Agr Univ, Coll Grassland Sci, Grassland Agri Husb Res Ctr, Qingdao 266109, Peoples R China. RP Sun, J (通讯作者)，Qingdao Agr Univ, Coll Grassland Sci, Grassland Agri Husb Res Ctr, Qingdao 266109, Peoples R China. EM sunjuan@qau.edu.cn TC 5 Z9 6 PD OCT PY 2021 VL 193 AR 104586 DI 10.1016/j.jaridenv.2021.104586 EA JUN 2021 UT WOS:000681241200001 DA 2023-03-23 ER PT J AU Shen, H Dong, SK DiTommaso, A Xiao, JN Zhi, YL AF Shen, Hao Dong, Shikui DiTommaso, Antonio Xiao, Jiannan Zhi, Yangliu TI N deposition may accelerate grassland degradation succession from grasses-and sedges-dominated into forbs-dominated in overgrazed alpine grassland systems on Qinghai-Tibetan Plateau SO ECOLOGICAL INDICATORS DT Article AB Alpine grasslands are sensitive to grazing and atmospheric nitrogen (N) deposition. Despite increases in N deposition, few field studies have assessed the effects of grazing in conjunction with increased N deposition on alpine grassland vegetation. In this two-year field study, we examined the effects of overgrazing and overgrazing plus N deposition on ecophysiological processes of alpine grassland plants at the functional group level. We found that both overgrazing and overgrazing plus N deposition altered species composition and the dominance of three plant functional groups (grasses, sedges, and forbs) in an alpine meadow and alpine steppe. In the overgrazing and overgrazing plus N deposition treatments, forbs dominated the plant community. Grass and sedge dominance decreased substantially, relative to a ungrazed treatment. The underlying eco-physiological processes that led to the forb-dominated plant community differed between the overgrazing and overgrazing plus N deposition treatments. Overgrazing plus N deposition increased forb dominance both directly by selective herbivory and indirectly by enhancing forb photosynthetic rates. Our results suggest that overgrazing concomitant with increases in N deposition will likely shift the plant community composition of alpine grasslands on the Qinghai-Tibetan Plateau from grass/sedge communities to forb-dominated communities in the future. C1 [Shen, Hao; Dong, Shikui] Beijing Forestry Univ, Coll Grassland Sci, Beijing 100083, Peoples R China. [Shen, Hao; Dong, Shikui; Xiao, Jiannan; Zhi, Yangliu] Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. [Shen, Hao; DiTommaso, Antonio] Cornell Univ, Sch Integrat Plant Sci, Soil & Crop Sci, Ithaca, NY 14853 USA. RP Dong, SK (通讯作者)，Beijing Forestry Univ, Coll Grassland Sci, Beijing 100083, Peoples R China.; Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. EM dongshikui@sina.com; ad97@cornell.edu TC 4 Z9 5 PD OCT PY 2021 VL 129 AR 107898 DI 10.1016/j.ecolind.2021.107898 EA JUN 2021 UT WOS:000685517300002 DA 2023-03-23 ER PT J AU Li, HY Qiu, YZ Yao, T Han, DR Gao, YM Zhang, JG Ma, YC Zhang, HR Yang, XL AF Li, Haiyun Qiu, Yizhi Yao, Tuo Han, Dongrong Gao, Yamin Zhang, Jiangui Ma, Yachun Zhang, Huirong Yang, Xiaolei TI Nutrients available in the soil regulate the changes of soil microbial community alongside degradation of alpine meadows in the northeast of the Qinghai-Tibet Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The alpine meadow in the Qinghai-Tibet Plateau has been seriously degraded due to human activities and climate change in recent decades. Understanding the changes of the soil microbial community in response to the degradation process helps reveal the mechanism underlying the degradation process of alpine meadows. We surveyed and analyzed changes of the vegetation, soil physicochemical properties, and soil microbial community in three degradation levels, namely, non-degradation (ND), moderate degradation (MD), and severe degradation (SD), of the alpine meadows in the northeastern Qinghai-Tibet Plateau. We found that as the level of degradation increased, plant cover, plant density (PD), above-ground biomass (AGB), plant Shannon-Wiener index (PS), soil water content (SWC), soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), and available potassium (AK) decreased significantly, while the soil pH increased from 7.20 to 8.57. Alpine meadow degradation significantly changed the composition of soil bacterial and fungal communities but had no significant impact on the diversity of the microbial communities. Functional predictions indicated that meadow degradation increased the relative abundances of aerobic_chemoheterotrophy, undefined_saprotroph, and plant_pathogen, likely increasing the risk of plant diseases. Redundancy analysis revealed that in ND, the soil microbial community was mainly regulated by PS, PH, PD, SWC, and soil pH. In MD, the soil microbial community was regulated by the soil's available nutrients and SOC. In SD, the soil microbial community was not only regulated by the soil's available nutrients but also influ-enced by plant characteristics. These results indicate that during alpine meadow degradation, while the changes in the plants and soil environmental factors both affect the composition of the soil microbial community, the influence of soil factors is greater. The soil's available nutrients are the main driving factors regulating the change in the soil microbial community's composition alongside degradation levels. (c) 2021 Elsevier B.V. All rights reserved. C1 [Li, Haiyun] Lanzhou Univ, Collaborat Innovat Ctr Western Ecol Safety, Lanzhou 730000, Peoples R China. [Qiu, Yizhi] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Yao, Tuo; Han, Dongrong; Gao, Yamin; Zhang, Jiangui; Ma, Yachun; Zhang, Huirong; Yang, Xiaolei] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Peoples R China. RP Li, HY (通讯作者)，Lanzhou Univ, Collaborat Innovat Ctr Western Ecol Safety, Lanzhou 730000, Peoples R China. EM lihaiyun@lzu.edu.cn TC 19 Z9 19 PD OCT 20 PY 2021 VL 792 AR 148363 DI 10.1016/j.scitotenv.2021.148363 EA JUN 2021 UT WOS:000689486600004 DA 2023-03-23 ER PT J AU Zhou, TC Zong, N Sun, J Hou, G Shi, PL AF Zhou, Tiancai Zong, Ning Sun, Jian Hou, Ge Shi, Peili TI Plant nitrogen concentration is more sensitive in response to degradation than phosphorus concentration in alpine meadow SO ECOLOGICAL ENGINEERING DT Article AB Exploring the early warning signals of plant and soil characteristics in response to degradation is of great theoretical significance to illuminate the underlying driving mechanism of alpine meadow degradation. Here, in alpine meadow of Damxung County on the Tibetan Plateau, a field survey along degradation gradients was conducted to measure plant and soil properties: from non-degradation to severely degradation, simultaneous impairments in plant total biomass, plant coverage, plant N concentration, soil moisture, soil total C and N were detected, which significantly (P<0.05) decreased by 85.36%, 54.30%, 25.23%, 26.95%, 28.94% and 12.85% in sequence, while no significant change in plant P concentration was observed. As grassland degradation increased, a consistent decrease of plant N: P ratios (<14) not only demonstrated that N was a strong limiting factor for plants growth, but also supported our hypothesis that plant N concentration was more sensitive in response to degradation than plant P concentration. Path analyses further indicated that soil moisture and soil total nitrogen were the most critical factors that mediated the plant N: P in response to degradation. Although our findings suggested that N resorption efficiency was improved after grassland degradation, the increase in grassland degradation would enhance the N concentration decoupling from P concentration, which in turn might further exacerbate the N limitation and the degradation in alpine ecosystems. The early-warning signals of grassland degradation obtained here not only can improve the understanding of grassland degradation, but also can provide guidance for the restoration and management of degraded alpine meadow on the Tibetan Plateau. C1 [Zhou, Tiancai; Zong, Ning; Hou, Ge; Shi, Peili] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Zhou, Tiancai; Zong, Ning; Hou, Ge; Shi, Peili] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. [Sun, Jian] Chinese Acad Sci, Inst Tibetan Plateau Res, State Key Lab Tibetan Plateau Earth Syst Sci LAT, Beijing 100101, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. EM zhoutc.18b@igsnrr.ac.cn; zongning@igsnrr.ac.cn; sunjian@igsnrr.ac.cn; shipl@igsnrr.ac.cn TC 3 Z9 3 PD NOV 1 PY 2021 VL 169 AR 106323 DI 10.1016/j.ecoleng.2021.106323 EA JUN 2021 UT WOS:000674452700008 DA 2023-03-23 ER PT J AU Niu, YJ Yang, SW Zhu, HM Zhou, JW Chu, B Ma, SJ Hua, R Wang, T Hua, LM AF Niu, Yujie Yang, Siwei Zhu, Huimin Zhou, Jianwei Chu, Bin Ma, Sujie Hua, Rui Wang, Ting Hua, Limin TI Plant community distribution induced by microtopography due to soil cracks developed in overgrazed alpine meadows on the Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Microtopographic variation is a common feature of natural ecosystems. On the Tibetan Plateau, this variation includes soil cracking that influences the dynamics of soil nutrients and seed trapping, which further affect species distributions. Despite their importance, cracks in alpine meadows have rarely been reported, and the effects of cracks on soil properties and plant distribution are poorly understood. Therefore, we investigated the effects of microtopography induced by cracking on the soil properties, seed trapping, and plant community composition of crack mosaics in alpine meadows. The study focused on healed cracks that can recover from winter cracking and have not yet become irreversibly degraded. The results showed that the number of seeds in the healed cracks was significantly greater than that in the raised areas, by 2.37-times. The soil chemical parameters in the healed cracks were significantly higher than those in the raised areas. There were also significant differences in the soil physical parameters between these two positions of the mosaic. Differences in species richness and importance values, and their dynamics (2013-2018), were correlated with these two spatial positions in the crack mosaics. Soil physical and chemical parameters together explained 71% of the plant community composition on the crack mosaics, and the interaction effect explained 52.4%. To some extent, crack mosaics composed of microtopography units favour the conservation of water and nutrients in the healed-crack portion of the mosaic. We propose that cutting kobresia lawns will facilitate the repair of ecological processes and initiate a natural recovery in overgrazed alpine meadows. C1 [Niu, Yujie; Zhu, Huimin; Zhou, Jianwei; Chu, Bin; Hua, Rui; Wang, Ting; Hua, Limin] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Gansu, Peoples R China. [Niu, Yujie] Univ Bayreuth, BayCEER, Dept Disturbance Ecol, Bayreuth, Germany. [Yang, Siwei] Sichuan Acad Grassland Sci, Inst Grassland Ecol, Chengdu, Peoples R China. [Zhou, Jianwei; Chu, Bin; Hua, Rui; Hua, Limin] Gansu Agr Univ, Natl Forestry & Grassland Adm, Engn & Technol Res Ctr Alpine Rodent Pest Control, Lanzhou, Gansu, Peoples R China. [Ma, Sujie] Tibet Agr & Anim Husb Univ, Coll Anim Sci, Nyingchi, Peoples R China. RP Niu, YJ; Hua, LM (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Gansu, Peoples R China. EM yujie.niu@uni-bayreuth.de; hualm@gsau.edu.cn TC 1 Z9 1 PD JUL 15 PY 2021 VL 32 IS 11 BP 3167 EP 3179 DI 10.1002/ldr.3882 EA JUN 2021 UT WOS:000659738600001 DA 2023-03-23 ER PT J AU Wu, JQ Wang, HY Li, G Wu, JH Ma, WW AF Wu, Jiangqi Wang, Haiyan Li, Guang Wu, Jianghua Ma, Weiwei TI Vertical and seasonal changes in soil carbon pools to vegetation degradation in a wet meadow on the Qinghai-Tibet Plateau SO SCIENTIFIC REPORTS DT Article AB Wet meadows provide opportunities to decrease carbon dioxide (CO2) and methane (CH4) released into the atmosphere by increasing the soil organic carbon (SOC) stored in wetland systems. Although wet meadows serve as the most important and stable C sinks, there has been very few investigations on the seasonal distributions of SOC fractions in high-altitude wet meadows. Here, we studied the effects of four vegetation degradation levels, non-degraded (ND), lightly degraded (LD), moderately degraded (MD), and heavily degraded (HD), on the measured vertical and seasonal changes of SOC and its different fractions. Among these vegetation degradation levels, 0-10 and 10-20 cm soil depths in ND plots had significantly higher SOC contents than the other degradation levels had throughout the year. This is attributed to the relatively greater inputs of aboveground plant litter and richer fine-root biomass in ND plots. Particulate organic carbon (POC) and light fraction organic carbon (LFOC) showed similar vertical and seasonal variations in autumn, reaching a minimum. Moreover, microbial biomass (MBC) and easily oxidizable organic carbon (EOC) contents were highest in summer and the smallest in winter, while dissolved organic carbon (DOC) content was highest in spring and lowest in summer, and were mainly concentrated in the 0-20 cm layer. Pearson correlation analysis indicated that soil properties and aboveground biomass were significantly related to different SOC fractions. The results indicate that vegetation degradation reduces the accumulation of total SOC and its different fractions, which may reduce carbon sink capacity and soil quality of alpine wet meadows, and increase atmospheric environmental pressure. In addition, vegetation biomass and soil characteristics play a key role in the formation and transformation of soil carbon. These results strengthen our understanding of soil C dynamics, specifically related to the different C fractions as affected by vegetation degradation levels and soil depth, in wet meadow systems. C1 [Wu, Jiangqi; Wang, Haiyan; Li, Guang; Ma, Weiwei] Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China. [Wu, Jianghua] Mem Univ Newfoundland, Sch Sci & Environm, 20 Univ Dr, Corner Brook, NF A2H 5G4, Canada. RP Li, G (通讯作者)，Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China. EM liggsau@foxmail.com TC 5 Z9 5 PD JUN 10 PY 2021 VL 11 IS 1 AR 12268 DI 10.1038/s41598-021-90543-6 UT WOS:000663785600018 DA 2023-03-23 ER PT J AU Yuan, X Chen, Y Qin, WK Xu, TL Mao, YH Wang, Q Chen, KL Zhu, B AF Yuan, Xia Chen, Ying Qin, Wenkuan Xu, Tianle Mao, Yahui Wang, Qi Chen, Kelong Zhu, Biao TI Plant and microbial regulations of soil carbon dynamics under warming in two alpine swamp meadow ecosystems on the Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Increasing temperature plays important roles in affecting plant and soil microbial communities as well as ecological processes and functions in terrestrial ecosystems. However, mechanisms of warming influencing soil carbon dynamics associated with plant-microbe interactions remain unclear. In this study, open-top chambers (OTCs) experiments were carried out to detect the responses of plants, soil microbes, and SOC contents, physical fractions (by particle-size fractionation) and chemical composition (by solid-state C-13 NMR spectroscopy) to warming in two alpine swamp meadows (Kobresia humilis vs K. tibetica) on the Tibetan Plateau. Our results showed that four years of warming had significant influences on plant belowground biomass, microbial community and SOC contents in the K. humilis swamp meadow, but had much weaker or minor effects in the K. tibetica swamp meadow with water-logged status and lower level of warming. In the K. humilis swamp meadow, warming increased microbial biomass, C-hydrolysis gene abundance and N-acetylglucosaminidase enzyme activity. These positive effects of warming on microbial biomass and functions further increased soil dissolved inorganic nitrogen and alleviated the nitrogen limitation for plant growth, potentially leading to higher plant biomass. Therefore, increases in SOC and particulate organic carbon (POC) under warming were likely attributed to the higher C input with promoted plant biomass overweighting the simultaneous higher C degradation and release in the K. humilis swamp meadow. Conversely, warming marginally reduced soil alkyl C, which was likely associated with enhanced decomposition by fungi and gram-positive bacteria. Overall, the increases in unprotected POC and decreases in recalcitrant alkyl C demonstrate the sensitivity of SOC physical fractions as well as chemical composition to climate warming in the K. humilis alpine swamp meadow, and suggest that the overall stability of SOC might be lower despite the gain in the content of SOC after climate warming in this alpine swamp meadow. (c) 2021 Elsevier B.V. All rights reserved. C1 [Yuan, Xia; Chen, Ying; Qin, Wenkuan; Xu, Tianle; Zhu, Biao] Peking Univ, Key Lab Earth Surface Proc, Coll Urban & Environm Sci, Inst Ecol,Minist Educ, Beijing 100871, Peoples R China. [Mao, Yahui; Wang, Qi; Chen, Kelong] Qinghai Normal Univ, Coll Geog Sci, Xining 810008, Peoples R China. RP Zhu, B (通讯作者)，Peking Univ, Key Lab Earth Surface Proc, Coll Urban & Environm Sci, Inst Ecol,Minist Educ, Beijing 100871, Peoples R China. EM biaozhu@pku.edu.cn TC 12 Z9 13 PD OCT 10 PY 2021 VL 790 AR 148072 DI 10.1016/j.scitotenv.2021.148072 EA JUN 2021 UT WOS:000685282800010 DA 2023-03-23 ER PT J AU Dong, L Li, JJ Sun, J Yang, C AF Dong, Lin Li, Jingjing Sun, Juan Yang, Chao TI Soil degradation influences soil bacterial and fungal community diversity in overgrazed alpine meadows of the Qinghai-Tibet Plateau SO SCIENTIFIC REPORTS DT Article AB Over half of the alpine meadows in the Qinghai-Tibet Plateau (QTP) are degraded due to human activities. Soil degradation from overgrazing is the most direct cause of grassland degradation. It is thus important to synthesize the effects of multiple soil degradation indicators on the belowground biomass of plants and soil microorganisms in the degraded QTP. We studied the diversities and structures of soil bacterial and fungal communities using soil bacterial 16S rRNA and the fungal ITS gene under four degradation gradients, D1: lightly degraded, D2: moderately degraded, D3: highly degraded, and a non-degraded control site (CK). The bacterial Shannon diversity in D3 was significantly lower than that in D1 (p < 0.001), and the bacterial richness index in D3 was significantly lower than that in D1 (p < 0.001). There was no difference in soil fungal diversity among the different degradation levels; however, soil fungal richness decreased significantly from CK to D3. The phyla Actinobacteria, Acidobacteria and the genus Mortierella were differed significantly under the four degradation gradients. Plant litter mass and root C/N ratio were important factors associated with bacterial and fungal diversity and richness. These results indicated that alpine meadow degradation can lead to variations in both microbial diversity and the potential functioning of micro-organisms in the QTP. C1 [Dong, Lin; Li, Jingjing; Sun, Juan; Yang, Chao] Qingdao Agr Univ, Coll Grassland Sci, Grassland Agrihusb Res Ctr, Qingdao 266109, Peoples R China. RP Yang, C (通讯作者)，Qingdao Agr Univ, Coll Grassland Sci, Grassland Agrihusb Res Ctr, Qingdao 266109, Peoples R China. EM yangchao@qau.edu.cn TC 8 Z9 8 PD JUN 2 PY 2021 VL 11 IS 1 AR 11538 DI 10.1038/s41598-021-91182-7 UT WOS:000687322500100 DA 2023-03-23 ER PT J AU Liu, YX Liu, SL Wang, FF Sun, YX Li, MQ Wang, QB Yu, L AF Liu, Yixuan Liu, Shiliang Wang, Fangfang Sun, Yongxiu Li, Mingqi Wang, Qingbo Yu, Lu TI Responses of Habitat Quality and Animal Biodiversity to Grazing Activities on the Qinghai-Tibet Plateau SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Grazing activities perhaps lead to habitat quality degradation and animal biodiversity loss while the effects on the Qinghai-Tibet Plateau (QTP) is still relatively poorly studied. Based on the Integrated Valuation of Ecosystem Services and Tradeoffs model, geographical detector model and generalized linear mixed model, the responses of habitat quality and animal biodiversity to grazing activities at 5 km grid scale were analyzed. Results showed that the overall habitat quality on the QTP was high with 76.43% of the total area, and poor level accounted for 19.56%. High level habitat was mainly distributed in the southern part, while the poor level in the northern part. The mean grazing activity explanatory ability to habitat quality, bird species richness and mammal richness were 0.346, 0.430, and 0.354. The interaction effects between slope and grazing activities on habitat quality, bird species richness and mammal richness were the most important interaction effects, and the area affected by the interaction was 73.82, 46.00, and 46.17% of habitat quality, bird species richness and mammal richness, respectively. The interaction effects on habitat quality, bird species richness and mammal richness all showed "low in the northwest and high in the southeast". Grazing activities and habitat quality had a positive correlation while bird species richness, and mammal richness negative correlations. The spatial relationship of grazing activities of habitat quality was "higher in the middle and lower around the periphery", while the spatial distribution of grazing activities of bird species richness and mammal richness was "higher in the east and lower in the west". This study explicitly revealed the responses of habitat quality and animal biodiversity to grazing activities, thus providing references for biodiversity conservation on the QTP. C1 [Liu, Yixuan; Liu, Shiliang; Wang, Fangfang; Sun, Yongxiu; Li, Mingqi; Wang, Qingbo; Yu, Lu] Beijing Normal Univ, Sch Environm, Beijing, Peoples R China. RP Liu, SL (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing, Peoples R China. EM shiliangliu@bnu.edu.cn TC 6 Z9 6 PD JUN 2 PY 2021 VL 9 AR 681775 DI 10.3389/fevo.2021.681775 UT WOS:000661850000001 DA 2023-03-23 ER PT J AU Cai, SH Song, XN Hu, RH Guo, D AF Cai, Shuohao Song, Xiaoning Hu, Ronghai Guo, Da TI Ecosystem-Dependent Responses of Vegetation Coverage on the Tibetan Plateau to Climate Factors and Their Lag Periods SO ISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION DT Article AB The spatiotemporal variation characteristics of the Normalized Difference Vegetation Index (NDVI) and its climate response patterns are of significance in deepening our understanding of regional vegetation and climate change. The response of vegetation to climate factors varies spatially and may have lag periods. In this paper, we studied the spatiotemporal responses of vegetation to climatic factors on an ecosystem-dependent scale using GIMMS NDVI3g data and climatic parameters. Pure pixels with a single vegetation type were firstly extracted to reduce the influence of mixed vegetation types. Then, a lag correlation analysis was used to explore the lag effects of climatic parameters affecting NDVI. Finally, the stepwise regression method was adopted to calculate the regression equation for NDVI and meteorological data with the consideration of effect lag times. The results show that precipitation has significant lag effects on vegetation. Temperature is the main climatic factor that affects most vegetation types at the start of growing season. At the end of growing season, the temperate desert, temperate steppe, and temperate desert steppe are greatly affected by precipitation. Moreover, the alpine steppe, alpine desert, alpine meadow, and alpine sparse vegetation are greatly affected by temperature. The needleleaf forest, subalpine scrub, and broadleaf evergreen forest are sensitive to sunshine percentage during almost the whole growing season. These findings could contribute to a better understanding of the drivers and mechanisms of vegetation degradation on the Tibetan Plateau. C1 [Cai, Shuohao; Song, Xiaoning; Hu, Ronghai; Guo, Da] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. RP Song, XN (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM caishuohao19@mails.ucas.ac.cn; songxn@ucas.ac.cn; huronghai@ucas.ac.cn; guoda18@mails.ucas.ac.cn TC 5 Z9 5 PD JUN PY 2021 VL 10 IS 6 AR 394 DI 10.3390/ijgi10060394 UT WOS:000666956600001 DA 2023-03-23 ER PT J AU Guo, LM Chang, J Xu, HL Sun, WJ AF Guo Lin-mao Chang Juan Xu Hong-liang Sun Wen-jun TI Modelling plant canopy effects on water-heat exchange in the freezing-thawing processes of active layer on the Qinghai-Tibet Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB The effect of vegetation on the water-heat exchange in the freezing-thawing processes of active layer is one of the key issues in the study of land surface processes and in predicting the response of alpine ecosystems to climate change in permafrost regions. In this study, we used the simultaneous heat and water model to investigate the effects of plant canopy on surface and subsurface hydrothermal dynamics in the Fenghuoshan area of the Qinghai-Tibet Plateau by changing the leaf area index (LAI) and keeping other variables constant. Results showed that the sensible heat, latent heat and net radiation are increased with an increase in the LAI. However, the ground heat flux decreased with an increasing LAI. The annual total evapotranspiration and vegetation transpiration ranged from -16% to 9% and -100% to 15%, respectively, in response to extremes of doubled and zero LAI, respectively. There was a negative feedback between vegetation and the volumetric unfrozen water content at 0.2 m through changing evapotranspiration. The simulation results of soil temperature and moisture suggest that better vegetation conditions are conducive to maintaining the thermal stability of the underlying permafrost, and the advanced initial thawing time and increasing thawing rate of soil ice with the increase in the LAI may have a great influence on the timing and magnitude of supra-permafrost groundwater. This study quantifies the impact of vegetation change on surface and subsurface hydrothermal processes and provides a basic understanding for evaluating the impact of vegetation degradation on the water-heat exchange in permafrost regions under climate change. C1 [Guo Lin-mao; Chang Juan; Xu Hong-liang; Sun Wen-jun] Lanzhou Univ, Coll Earth & Environm Sci, Minist Educ, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Peoples R China. [Guo Lin-mao] Sichuan Univ, Coll Water Resource & Hydropower, State Key Lab Hydraul & Mt River Engn, Chengdu 610000, Peoples R China. RP Chang, J (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, Minist Educ, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Peoples R China. EM guolm17@lzu.edu.cn; changjuan@lzu.edu.cn; xuhl18@lzu.edu.cn; sunwj2019@lzu.edu.cn TC 1 Z9 1 PD JUN PY 2021 VL 18 IS 6 BP 1564 EP 1579 DI 10.1007/s11629-020-6335-5 UT WOS:000662311100011 DA 2023-03-23 ER PT J AU Hao, AH Duan, HC Wang, XF You, QG Peng, F Du, HQ Zhao, GH Liu, FY Li, CY Lai, CM Xue, X AF Hao, Aihua Duan, Hanchen Wang, Xufeng You, Quangang Peng, Fei Du, Heqiang Zhao, Guohui Liu, Feiyao Li, Chengyang Lai, Chimin Xue, Xian TI Different response of alpine meadow and alpine steppe to climatic and anthropogenic disturbance on the Qinghai-Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Climate change and anthropogenic disturbance are two main drivers for vegetation dynamics on the Qinghai-Tibetan Plateau (QTP). Alpine meadow and alpine steppe are the primary rangeland ecosystem types on the QTP. However, the vegetation trends of the two land cover types and the underlying mechanisms behind their variation remain under debate. In this study, we used Global Inventory Modeling and Mapping Studies (GIMMS) 3g Normalized Difference Vegetation Index (NDVI) (i.e., GIMMS NDVI3g) by coupling the Breaks for Additive Season and Trend (BFAST) model and the Boosted Regression Tree (BRT) model to analyze alpine meadow and alpine steppe vegetation trends on the QTP between 1982 and 2015. We also assessed vegetation variation response to climatic and anthropogenic indicators in conjunction with climatic and human footprint datasets. Results show that growing season NDVI (GSNDVI) values increased overall for both alpine meadow (0.0001 year-1, p = 0.33) and alpine steppe (0.0002 year-1, p < 0.05) throughout 1982-2015. Significant greening trends in both alpine meadow (0.0007 year-1; p < 0.05) and alpine steppe (0.0005 year-1; p < 0.05) ecosystems were obtained before 1998 and 2001, respectively. However, browning trends ascertained by GSNDVI (-0.0006 year-1; p = 0.12) in alpine meadows were observed throughout 1998-2015, while greening trends ascertained by GSNDVI (0.0002 year-1; p = 0.12) in alpine steppes were observed throughout during 2001-2015. Opposing trends in precipitation, solar radiation, and the Standardized Precipitation Evapotranspiration Index (SPEI) occurred before and after breakpoints in both ecosystems. For the alpine meadow ecosystem, adverse precipitation trends caused browning before 1998 followed by greening after 1998 in the Three-RiverSource National Park (TNP). Conversely, opposing changes in precipitation, solar radiation, and SPEI resulted in greening before 1998 followed by browning after 1998 in southern Tibet and the southeastern QTP. Alpine meadow vegetation trends were generally dominated by solar radiation before 1998 and jointly by precipitation and solar radiation after 1998. Prior to 2001 variation in alpine steppe greenness was controlled by precipitation, while after 2001 solar radiation dominated. Along with an increase in human footprint pressure (HFP) gradients, greenness trends gradually increased before 1998 but reversed after 1998 in the alpine meadow ecosystem. Additionally, greenness trends gradually decreased before 2001 but remained unchanged after 2001 for the alpine steppe ecosystem. These results highlight the different effects that climate change and anthropogenic disturbances have had on alpine meadow and alpine steppe ecosystems on the QTP over different time frames. (c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). C1 [Hao, Aihua; Duan, Hanchen; You, Quangang; Peng, Fei; Du, Heqiang; Liu, Feiyao; Li, Chengyang; Lai, Chimin; Xue, Xian] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. [Hao, Aihua; Liu, Feiyao; Li, Chengyang; Lai, Chimin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Xufeng] Chinese Acad Sci, Cold & Arid Regions Environm & Engn Res Inst, Heihe Remote Sensing Expt Res Stn, Key Lab Remote Sensing Gansu Prov, Lanzhou 730000, Peoples R China. [Wang, Xufeng] Univ New Hampshire, Earth Syst Res Ctr, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. [Zhao, Guohui] Chinese Acad Sci, Sci Big Data Ctr Cold & Arid Reg, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. [Peng, Fei] Tottori Univ, Arid Land Res Ctr, Int Platform Dryland Res & Educ, Hamasaka 1390, Tottori 6800001, Japan. RP Xue, X (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. EM xianxue@lzb.ac.cn TC 11 Z9 12 PD JUN PY 2021 VL 27 AR e01512 DI 10.1016/j.gecco.2021.e01512 UT WOS:000663455000011 DA 2023-03-23 ER PT J AU Sun, JJ Wang, PB Wang, HB Yu, XJ AF Sun, Jinjin Wang, Pengbin Wang, Haibo Yu, Xiaojun TI Changes in plant communities, soil characteristics, and microbial communities in alpine meadows degraded to different degrees by pika on the Qinghai-Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Alpine meadows, the main natural grassland on the Qinghai-Tibet Plateau, are the material basis of plateau meadow husbandry and ecological barrier. However, interference by pika (Ochotona curzoniae) has caused the degradation of alpine meadows to varying degrees. Knowledge about the vegetation, soil characteristics, and microbial community structure and function following degradation is limited. Thus, we studied the changes in vegetation, soil characteristics, and microbial communities in alpine meadows in Qinghai under different degrees of pika-induced degradation (non-degraded "CK"; lightly degraded "LD"; moderately degraded "MD"; and heavily degraded "HD"). The results showed coverage and biomass of the vegetation and species diversity decreased as the degree of degradation increased, and the dominant vegetation changed from members of the family Gramineae to poisonous plants. As the degree of degradation increased, total nitrogen (TN), available nitrogen (AN), and organic matter (OM) in the soil increased first and then decreased, while total potassium (TK), available potassium (AK), and available phosphorus (AP) increased. Among alpine meadows with different degrees of degradation, the alpha diversity of bacteria and fungi in the LD plot were significantly lower than that of CK, MD, and HD. Hierarchical clustering results showed that the composition of bacteria in the MD and HD plots was similar, and the classification of fungi among samples was more obvious. Results from a LEfSe showed that the majority of biomarker bacteria were found in the LD plot, but the majority of biomarker fungi were found in the MD plot. In addition, Tax4Fun and FUNGuild prediction analyses showed that compared with other plots, bacteria causing human infectious diseases were significantly higher in MD, there were more saprotrophic fungi in CK, and there was a significant increase in pathogenic fungi in MD and HD. Thus, pika-induced degradation affected vegetation, soil, and microbial community structure and function in the Qinghai-Tibetan Plateau, with fungal communities responding more strongly to the degradation than bacterial communities. (c) 2021 The Author(s). Published by Elsevier B.V. CC_BY_NC_ND_4.0 C1 [Sun, Jinjin; Wang, Pengbin; Yu, Xiaojun] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ,Sino US Ctr Grassland Ecosyst Susta, Lanzhou, Gansu 730070, Peoples R China. [Wang, Haibo] Grassland Working Stn Guoluo State, Qinghai 814000, Peoples R China. RP Yu, XJ (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ,Sino US Ctr Grassland Ecosyst Susta, Lanzhou, Gansu 730070, Peoples R China. EM yuxj@gsau.edu.cn TC 3 Z9 4 PD JUN PY 2021 VL 27 AR e01621 DI 10.1016/j.gecco.2021.e01621 UT WOS:000663455600006 DA 2023-03-23 ER PT J AU Wu, GL Cheng, Z Alatalo, JM Zhao, JX Liu, Y AF Wu, Gao-Lin Cheng, Zhen Alatalo, Juha Mikael Zhao, Jingxue Liu, Yu TI Climate Warming Consistently Reduces Grassland Ecosystem Productivity SO EARTHS FUTURE DT Article AB Future climate may profoundly impact the functioning of terrestrial ecosystems. However, we do not know well how the functioning of different types of grassland ecosystems is associated with variation in temperature and precipitation. Here, we used long-term field measurements to examine how climatic changes between the 1980s and the 2010s (i.e., growing season temperature, precipitation, habitat moisture index, solar radiation, and sunshine duration) have affected aboveground net primary productivity (ANPP) for all major grassland types in northern China. We found that ANPP consistently declined over the 30-year period across all types of grassland, on average by about 6.1%. Warming, associated with increased solar radiation and, hence, soil temperature, was the primary factor driving the decrease of ANPP. We further show that ANPP was more sensitive to climate change in alpine and lowland grasslands than in temperate grasslands. Together, our findings indicate that climate warming consistently reduces plant productivity of different types of grassland ecosystems, and emphasize the importance of soil temperature in driving the decline in grassland productivity under climate change. C1 [Wu, Gao-Lin; Cheng, Zhen; Zhao, Jingxue; Liu, Yu] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling, Shaanxi, Peoples R China. [Wu, Gao-Lin; Liu, Yu] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Area, Xining, Peoples R China. [Wu, Gao-Lin] CAS Ctr Excellence Quaternary Sci & Global Change, Xian, Peoples R China. [Alatalo, Juha Mikael] Qatar Univ, Coll Arts & Sci, Dept Biol & Environm Sci, Doha, Qatar. [Alatalo, Juha Mikael] Qatar Univ, Environm Sci Ctr, Doha, Qatar. [Zhao, Jingxue] Lanzhou Univ, Inst Innovat Ecol & Coll Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. RP Wu, GL (通讯作者)，Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling, Shaanxi, Peoples R China.; Wu, GL (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Area, Xining, Peoples R China.; Wu, GL (通讯作者)，CAS Ctr Excellence Quaternary Sci & Global Change, Xian, Peoples R China. EM gaolinwu@gmail.com TC 21 Z9 20 PD JUN PY 2021 VL 9 IS 6 AR e2020EF001837 DI 10.1029/2020EF001837 UT WOS:000666656400003 DA 2023-03-23 ER PT J AU Zhao, DS Zhu, Y Wu, SH Zheng, D AF Zhao, Dongsheng Zhu, Yu Wu, Shaohong Zheng, Du TI Projection of vegetation distribution to 1.5 degrees C and 2 degrees C of global warming on the Tibetan Plateau SO GLOBAL AND PLANETARY CHANGE DT Article AB Previous studies have identified vegetation shifts on the Tibetan Plateau in response to climate change. However, the speed and direction of these changes in alpine vegetation are not well understood. To quantify the responses of the distribution of alpine vegetation to global warming of 1.5 degrees C or 2 degrees C, BIOME4 was modified using the Penman-Monteith equation to estimate the reference evapotranspiration, and was run with projected climate data under the RCP4.5 and RCP8.5 scenarios. Gradients of temperature (1-5 degrees C) and precipitation (- 30%-30%) were used to examine the sensitivity of changes in the vegetation pattern to climate. This study suggests that forests on the Tibetan Plateau will expand northwestward with climate warming. Among all forest types, the distribution area of broad-leaved forests will show the greatest increase, whereas mixed needle-broad-leaved forests will show the greatest percentage decrease (similar to 45.5%) relative to the baseline period. Climate warming will result in alpine shrub expansion towards the interior of the Tibetan Plateau, with an average center shift of 309 km under the RCP4.5 scenario with a warming of 1.5 degrees C. A proportion of alpine meadow will be replaced by alpine shrub, causing it to shrink by similar to 6.8% under RCP4.5 with a warming of 1.5 degrees C and by similar to 15.5% under RCP8.5 with a warming of 2 degrees C. We conclude that all vegetation types on the Tibetan Plateau are susceptible to a warming climate. Increasing temperatures will move the vegetation boundaries northwestward and this trend will be enhanced by increases in precipitation. Understanding the response of vegetation patterns to warming will facilitate better strategies for carbon storage management. C1 [Zhao, Dongsheng; Zhu, Yu; Wu, Shaohong; Zheng, Du] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing, Peoples R China. [Zhu, Yu; Wu, Shaohong; Zheng, Du] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. RP Zhao, DS (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing, Peoples R China. EM zhaods@igsnrr.ac.cn TC 10 Z9 10 PD JUL PY 2021 VL 202 AR 103525 DI 10.1016/j.gloplacha.2021.103525 EA MAY 2021 UT WOS:000663732300003 DA 2023-03-23 ER PT J AU Xu, AC Zhong, MJ Tang, K Wang, XY Yang, C Xu, HG Yi, JF Liu, W Zhang, CL Hu, JH AF Xu, Aichun Zhong, Maojun Tang, Ke Wang, Xiaoyi Yang, Chen Xu, Haigen Yi, Jianfeng Liu, Wei Zhang, Chunlan Hu, Junhua TI Multidimensional diversity of bird communities across spatial variation of land cover in Zoige on the eastern Qinghai-Tibetan Plateau SO AVIAN RESEARCH DT Article AB Background Spatial variation of land cover can result in the changes of community similarities and biotic homogenization, whereby the increasing similarity would reduce the adaptive capacity of biotic assemblages to further disturbance, and degenerate ecosystem services they offer. However, it remains scarce to integrate multidimensional diversity for unveiling how variations in land cover may influence the patterns and processes of biotic homogenization in the Anthropocene. In this study, we examined how spatial variation of land cover could alter taxonomic, phylogenetic and functional homogenization of bird communities simultaneously in a compound ecosystem of Zoige Marsh on the eastern Qinghai-Tibetan Plateau. Acting as the largest alpine marsh and peatland in the world, Zoige Marsh has undergone great changes in the land cover pattern due to climate change and anthropogenic activities. Methods We conducted transect surveys for bird communities over six years (2014-2019) during breeding seasons in four main land cover types (meadow, woodland, village and marsh), representing the spatial variation of land covers in the study area. We compared multidimensional diversity (taxonomic, phylogenetic and functional diversity) among land covers to assess the effects of spatial variation in land cover type on bird communities, particularly whether this variation has homogenized biotic communities. Results Bird communities during breeding seasons were different and complementary in the four land covers. Taxonomic, phylogenetic and functional similarities were significantly lower in meadow than in the other three types, i.e. woodland, village and marsh. However, when we controlled for the effects of taxonomic similarities, the pattern of phylogenetic similarities almost reversed, with the highest standardized effect size (SES) phylogenetic similarity in meadow; and we found no significant difference in SES functional similarity among land covers. Conclusions Our results suggest that spatial variation of land cover can play a crucial role in regulating multiple dimensions of bird diversity in Zoige Marsh. The findings indicate that taxonomic, phylogenetic and functional homogenization of bird communities may differently response to the variation of land covers. It thus highlights not only the relative roles of different land covers in maintaining biodiversity and community structures of birds, but also the urgency of retarding ecosystem degradations on the eastern Qinghai-Tibetan Plateau. C1 [Xu, Aichun; Yang, Chen] China Jiliang Univ, Coll Life Sci, Hangzhou 310018, Peoples R China. [Zhong, Maojun; Tang, Ke; Wang, Xiaoyi; Hu, Junhua] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Xu, Haigen; Yi, Jianfeng; Liu, Wei] Nanjing Inst Environm Sci, Minist Ecol & Environm China, Nanjing 210042, Peoples R China. [Zhang, Chunlan] Guangdong Acad Sci, Guangdong Key Lab Anim Conservat & Resource Utili, Guangdong Publ Lab Wild Anim Conservat & Utilizat, Inst Zool, Guangzhou 510260, Peoples R China. RP Hu, JH (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China.; Zhang, CL (通讯作者)，Guangdong Acad Sci, Guangdong Key Lab Anim Conservat & Resource Utili, Guangdong Publ Lab Wild Anim Conservat & Utilizat, Inst Zool, Guangzhou 510260, Peoples R China. EM chunlanzh@qq.com; hujh@cib.ac.cn TC 2 Z9 2 PD MAY 22 PY 2021 VL 12 IS 1 AR 25 DI 10.1186/s40657-021-00259-4 UT WOS:000653025000001 DA 2023-03-23 ER PT J AU Liu, SS Kruse, S Scherler, D Ree, RH Zimmermann, HH Stoof-Leichsenring, KR Epp, LS Mischke, S Herzschuh, U AF Liu, Sisi Kruse, Stefan Scherler, Dirk Ree, Richard H. Zimmermann, Heike H. Stoof-Leichsenring, Kathleen R. Epp, Laura S. Mischke, Steffen Herzschuh, Ulrike TI Sedimentary ancient DNA reveals a threat of warming-induced alpine habitat loss to Tibetan Plateau plant diversity SO NATURE COMMUNICATIONS DT Article AB Studies along elevational gradients worldwide usually find the highest plant taxa richness in mid-elevation forest belts. Hence, an increase in upper elevation diversity is expected in the course of warming-related treeline rise. Here, we use a time-series approach to infer past taxa richness from sedimentary ancient DNA from the south-eastern Tibetan Plateau over the last similar to 18,000 years. We find the highest total plant taxa richness during the cool phase after glacier retreat when the area contained extensive and diverse alpine habitats (14-10 ka); followed by a decline when forests expanded during the warm early- to mid-Holocene (10-3.6 ka). Livestock grazing since 3.6 ka promoted plant taxa richness only weakly. Based on these inferred dependencies, our simulation yields a substantive decrease in plant taxa richness in response to warming-related alpine habitat loss over the next centuries. Accordingly, efforts of Tibetan biodiversity conservation should include conclusions from palaeoecological evidence. C1 [Liu, Sisi; Kruse, Stefan; Zimmermann, Heike H.; Stoof-Leichsenring, Kathleen R.; Epp, Laura S.; Herzschuh, Ulrike] Alfred Wegener Inst, Helmholtz Ctr Polar & Marine Res, Polar Terr Environm Syst, Potsdam, Germany. [Liu, Sisi; Herzschuh, Ulrike] Univ Potsdam, Inst Environm Sci & Geog, Potsdam, Germany. [Scherler, Dirk] GFZ German Res Ctr Geosci, Potsdam, Germany. [Scherler, Dirk] Free Univ Berlin, Inst Geol Sci, Berlin, Germany. [Ree, Richard H.] Field Museum, Dept Sci & Educ, Negaunee Integrat Res Ctr, Chicago, IL USA. [Mischke, Steffen] Univ Iceland, Inst Earth Sci, Reykjavik, Iceland. [Herzschuh, Ulrike] Univ Potsdam, Inst Biochem & Biol, Potsdam, Germany. RP Herzschuh, U (通讯作者)，Alfred Wegener Inst, Helmholtz Ctr Polar & Marine Res, Polar Terr Environm Syst, Potsdam, Germany.; Herzschuh, U (通讯作者)，Univ Potsdam, Inst Environm Sci & Geog, Potsdam, Germany.; Herzschuh, U (通讯作者)，Univ Potsdam, Inst Biochem & Biol, Potsdam, Germany. EM Ulrike.Herzschuh@awi.de TC 10 Z9 13 PD MAY 20 PY 2021 VL 12 IS 1 AR 2995 DI 10.1038/s41467-021-22986-4 UT WOS:000658762400005 DA 2023-03-23 ER PT J AU Shi, GX Yao, BQ Liu, YJ Pan, JB Jiang, SJ Wang, YB Wang, ZB Feng, HY Zhou, HK AF Shi, Guoxi Yao, Buqing Liu, Yongjun Pan, Jianbin Jiang, Shengjing Wang, Yibo Wang, Zhibo Feng, Huyuan Zhou, Huakun TI The effects of long-term warming on arbuscular mycorrhizal fungal communities depend on habitat type on the Qinghai-Tibet Plateau SO APPLIED SOIL ECOLOGY DT Article AB Arbuscular mycorrhizal fungi (AMF) are widespread root-associated microorganisms that participate in many ecosystem processes. However, the response of AMF communities to global warming still remains poorly understood, especially in high-altitude regions. This study investigated the responses of AMF communities to 17-year experimental warming with open top chambers in two habitat types (i.e., shrubland and meadow) of the alpine meadow ecosystem of the Qinghai-Tibet Plateau. For this, 454-pyrosequencing was used and the main ecological processes that structure AMF communities were inferred based on distributions of species abundance and phylogenetic patterns. A total of 110 different AMF phylotypes (shrubland habitat: 102; meadow habitat: 91) were identified in both habitats, predominantly belonging to Glomeraceae. Eighty AMF phylotypes were found in both habitats, and phylotypes affiliated with Acaulosporaceae and Archaeosporaceae were only found in the shrubland habitat. Warming did not affect AMF diversity or community composition in the shrubland habitat; however, in the meadow habitat, warming caused a decline of AMF species richness by 45.6%. Moreover, the taxon composition of AMF communities was changed via the negative influence of root biomass in the meadow habitat. Mandelbrot, based on the niche process, was the best-fitting model for all fungal data sets in both habitats, indicating that fungal community dynamics under warming treatments matched niche-based processes in both habitats. Moreover, the phylogenetic structure of AMF communities was always phylogenetically clustered regardless of warming in the shrubland habitat. However, the phylogenetic structure changed from phylogenetic clustering of the control treatment to random of warming treatment in the meadow habitat. This suggests that in the shrubland habitat, warming does not change the central ecological process that structures AMF communities, but rather, leads to the transformation of the central process from environmental filtration to the neutralization of habitat filtration and competition exclusion in the meadow habitat. In summary, these results indicate that the effect of long-term warming on the assemblage of AMF communities depends on the habitat type. This illustrates that maintaining a high habitat type complexity is conducive for the response of alpine meadow ecosystems to climate warming. C1 [Shi, Guoxi; Wang, Yibo; Wang, Zhibo] Tianshui Normal Univ, Coll Bioengn & Biotechnol, Key Lab Utilizat Agr Solid Waste Resources, Tianshui 741000, Peoples R China. [Shi, Guoxi; Yao, Buqing; Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining 810008, Peoples R China. [Liu, Yongjun; Pan, Jianbin; Jiang, Shengjing; Feng, Huyuan] Lanzhou Univ, Sch Life Sci, MOE Key Lab Cell Act & Stress Adaptat, Lanzhou 730000, Peoples R China. RP Feng, HY (通讯作者)，Lanzhou Univ, Room 408,Tianyan Bldg,Tianshui South Rd 222, Lanzhou 730000, Peoples R China.; Zhou, HK (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xinning Mad 23, Xining 810008, Peoples R China. EM bqyao@nwipb.cas.cn; fenghy@lzu.edu.cn; hkzhou@nwipb.cas.cn TC 4 Z9 5 PD NOV PY 2021 VL 167 AR 104030 DI 10.1016/j.apsoil.2021.104030 EA MAY 2021 UT WOS:000694919000012 DA 2023-03-23 ER PT J AU Li, Y Wang, GX Bing, HJ Wang, T Huang, KW Song, CL Chen, XP Hu, ZY Rui, PF Song, XY Chang, RY AF Li, Yang Wang, Genxu Bing, Haijian Wang, Tao Huang, Kewei Song, Chunlin Chen, Xiaopeng Hu, Zhaoyong Rui, Pengfei Song, Xiaoyan Chang, Ruiying TI Watershed scale patterns and controlling factors of ecosystem respiration and methane fluxes in a Tibetan alpine grassland SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Ecosystem respiration (Re) and methane (CH4) fluxes are two important soil-atmosphere carbon exchange processes that have been well documented at the local scale. However, the spatial patterns and controlling factors of these processes remain unclear in the Tibetan alpine permafrost region at the watershed scale. We conducted a two-year field monitoring study of Re and CH4 fluxes at three altitudinal positions on shady and sunny slopes in a Tibetan alpine grassland to determine the spatial variability in the two processes and to identify their underlying mechanisms. The microbial factor had a controlling effect on Re spatial variability in alpine grassland watersheds. The lower soil temperature and soil organic matter content at the upper slope positions on the shady slopes inhibited Re because they reduced the soil microbial activity. We found that the alpine grassland to be a net sink of atmospheric CH4, and the average CH4 flux rates exhibited large spatial variance ranging from 1.60 to 10.48 mu g CH4 m(-2) h(-1) within the watersheds. The spatial variability in soil volumetric water content explained 76% of the variation in CH4 fluxes within the watersheds. We suggest that the influence of permafrost on hydrologic conditions may increase the spatial variability of soil moisture (measured as soil volumetric water content and water-filled pore space) in alpine grassland watersheds, and generally form poorly drained landscape at the lower slope position where Re and CH4 uptake are inhibited. Our results highlight the indirect effects of terrain and permafrost on Re and CH4 fluxes through their effects on biophysiochemical factors. We recommend that the spatial variability in Re and CH4 fluxes at the watershed scale of Tibetan alpine grassland should be given more attention in earth system models, especially the variability of CH4 fluxes with altitudinal position. C1 [Li, Yang; Wang, Genxu; Song, Chunlin; Hu, Zhaoyong] Sichuan Univ, Coll Water Resource & Hydropower, State Key Lab Hydraul & Mt River Engn, Chengdu, Sichuan, Peoples R China. [Wang, Genxu; Bing, Haijian; Wang, Tao; Huang, Kewei; Chang, Ruiying] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Chen, Xiaopeng] Shanxi Agr Univ, Coll Grassland Sci, Taigu 030801, Peoples R China. [Rui, Pengfei] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Lanzhou 730000, Peoples R China. [Song, Xiaoyan] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. RP Chang, RY (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. EM changruiying@imde.ac.cn TC 0 Z9 0 PD AUG 15 PY 2021 VL 306 AR 108451 DI 10.1016/j.agrformet.2021.108451 EA MAY 2021 UT WOS:000659137200017 DA 2023-03-23 ER PT J AU Li, JX Li, XL Gao, J Shi, Y Ma, GL Ka-zhao-cai-rang AF Li, Jie-xia Li, Xi-lai Gao, Jay Shi, Yan Ma, Ge-liang Ka-zhao-cai-rang TI Influences of pika and simulated grazing disturbances on bare patches of alpine meadow in the Yellow River Source Zone SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Bare patches in alpine meadow are the main manifestation of its degradation. The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances caused by plateau pika (Ochotona curzoniae) population and simulated grazing via artificial mowing both independently and interactively. The disturbance was set at three levels of high, medium and no disturbance (control group). Bare patches were mapped by from unmanned aerial vehicle (UAV) images with fine resolution of 1 cm obtained in August 2018 and August 2019 in ArcGIS. The results showed that the total area of bare patches decreased by 112.05 m(2) in sub-plots devoid of pika disturbance but increased by 126.37 m(2) in other sub-plots. The highest rate of increase is 89.02%. The individual effect of pika exceeds the joint effect of pika and mowing disturbances. The sole effect of mowing is lower than the joint effect of pika disturbance and intensive mowing, but higher than the joint influence of pika disturbance and moderate mowing. Strong pika disturbance (14 per sub-plot) caused the influence of mowing from moderate to intensive to increase by five-fold. The area of bare patches treated with moderate mowing and no pika disturbance decreased at the highest pace (-37.22%). Intensive mowing and medium density pikas (100 pikas/ha) are considered the thresholds at which the bare patches start to expand. Even if the meadow is mowed at the medium and high intensity, the area of bare patches can be significantly reduced if plateau pika population is controlled to a low level. ANOVA analysis and long-term macro-scale satellite-derived results reveal that pika disturbance is more important in causing the bare patches to change than simulated grazing. Therefore, it is more important to control the number of pikas than to reduce grazing intensity to prevent the expansion of bare patches in the degraded alpine meadow in the study area. C1 [Li, Jie-xia; Li, Xi-lai] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Li, Jie-xia; Li, Xi-lai] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Li, Jie-xia; Gao, Jay; Shi, Yan] Univ Auckland, Sch Environm, Private Bag 92019, Auckland, New Zealand. [Ma, Ge-liang; Ka-zhao-cai-rang] Grassland Integrated Profess Team Mongolian Auton, Huangnan 811500, Peoples R China. RP Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China.; Li, XL (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China.; Gao, J (通讯作者)，Univ Auckland, Sch Environm, Private Bag 92019, Auckland, New Zealand. EM jiexia_li@163.com; xilai-li@163.com; jg.gao@auckland.ac.nz; yshi917@auckland.ac.nz; mgl13909731924@163.com; 411271941@qq.com TC 0 Z9 0 PD MAY PY 2021 VL 18 IS 5 BP 1307 EP 1320 DI 10.1007/s11629-020-6196-y UT WOS:000650209900013 DA 2023-03-23 ER PT J AU Li, Q Yang, JY Guan, WH Liu, ZG He, GX Zhang, DG Liu, XN AF Li, Qiang Yang, Junyin Guan, Wenhao Liu, Zhigang He, Guoxing Zhang, Degang Liu, Xiaoni TI Soil fertility evaluation and spatial distribution of grasslands in Qilian Mountains Nature Reserve of eastern Qinghai-Tibetan Plateau SO PEERJ DT Article AB The study assessed the overall soil characteristics of grasslands on Qilian Mountains and rated the soil nutrient status with classification standard of the second national soil survey of China. Nemerow index method was used to evaluate the soil fertility of different grassland types. GIS was used to analyze the spatial distribution of the soil nutrients and provided a database for the grassland's ecological protection and restoration. The study graded the soil organic matter (SOM), total N, and available K at level 2 (high) or above for most regions, available soil-P at level 4, while the soil bulk density, total porosity and pH were 0.77-1.32 g cm(-3), 35.36-58.83% and 7.63-8.54, respectively. The rank of comprehensive soil fertility index was temperate steppe (TS) > alpine meadow (AM) > alpine steppe (AS) > upland meadow (UM) > alpine desert (AD) > lowland meadow (LM) > temperate desert steppe (TDS) > temperate desert (TD). The areas with high, medium and low soil fertility accounted for 63.19%, 34.24% and 2.57% of the total grassland area. Soil fertility of different grassland types had different main limiting factors, for instance, the pH, total N and SOM were the main factors limiting soil fertility in LM, while pH and available P were the main factors limiting soil fertility in UM, AM, TS and AS. In summary, the grassland soil fertility was generally at the mid-upper level, and the main limiting factors were found in the different types of the grasslands and their spatial distributions were figured out. Our findings also indicated that the typical grasslands and meadows may require phosphorus application, while for desert grasslands, both nitrogen and phosphorus were required to improve their comprehensive soil fertility and grassland productivity. C1 [Li, Qiang; Yang, Junyin; Guan, Wenhao; Liu, Zhigang; He, Guoxing; Zhang, Degang; Liu, Xiaoni] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou, Peoples R China. RP Liu, XN (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou, Peoples R China. EM liuxn@gsau.edu.cn TC 3 Z9 7 PD APR 23 PY 2021 VL 9 AR e10986 DI 10.7717/peerj.10986 UT WOS:000643559200002 DA 2023-03-23 ER PT J AU Gao, ZY Niu, FJ Lin, ZJ Luo, J AF Gao, Zeyong Niu, Fujun Lin, Zhanju Luo, Jing TI Fractal and multifractal analysis of soil particle-size distribution and correlation with soil hydrological properties in active layer of Qinghai-Tibet Plateau, China SO CATENA DT Article AB The soil hydrological properties (HPs) in active layers regulate soil water migration and affect the evolution of permafrost and biogeochemical cycles. There is relatively little understanding of the changes in soil HPs as a result of soil particle-size distribution (PSD) in the permafrost regions of the Qinghai-Tibet Plateau. In this study, different land-cover types, namely alpine wet meadow (AWM), extremely degraded wet meadow (EDWM), alpine meadow (AM), degraded alpine meadow (DAM), alpine steppe (AS), and alpine desert (AD), were used to determine the relationships between soil PSD and HPs. Soil HPs were determined using borehole nuclear magnetic resonance, and soil PSD (0-2 mm) was analyzed using fractal and multifractal theory. The results showed that vegetation degradation caused coarse soil particle accumulation in the root zone, reflected by the soil single-fractal dimension (D-v: 2.12-2.50). The D-v, values showed significant positive correlations with soil clay and silt content as well as a negative correlation with sand content. Results from the generalized fractal and singularity spectra suggested an even distribution of soil particles in the root zone of the AWM, AM, and AD sites. Vegetation degradation increased the soil PSD capacity dimension (D-0), information dimension (D-1), correlation dimension, D-1/D-0 ratio, and Holder exponent of order zero. This was indicative of a narrow soil PSD range and non-uniform soil texture in the root zone. Although capillary water dominated the total soil water content in the alpine soils, soil water composition was also dependent on the vegetation type and soil stratigraphic distribution. Soil particle composition and multifractal dimensions were found to be effective parameters for forecasting soil HPs in the non-mot zone of alpine soils. However, the presence of vegetation weakens the relationship between soil PSD and HPs. This study contributes to the accurate evaluation of hydrological and biogeochemical cycles in permafrost regions. C1 [Gao, Zeyong; Niu, Fujun; Lin, Zhanju; Luo, Jing] Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. RP Niu, FJ (通讯作者)，Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. EM niufujun@lzh.ac.cn TC 10 Z9 10 PD AUG PY 2021 VL 203 AR 105373 DI 10.1016/j.catena.2021.105373 EA APR 2021 UT WOS:000654354000065 DA 2023-03-23 ER PT J AU Qi, XE Wang, C He, TJ Ding, F Li, AR Zhang, XF An, LZ Xu, SJ AF Qi, Xing-E Wang, Chen He, Tianjiao Ding, Fan Li, Aorui Zhang, Xinfang An, Lizhe Xu, Shijian TI Changes in alpine grassland type drive niche differentiation of nitrifying communities on the Qinghai-Tibetan Plateau SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB Nitrification is a critical process of nitrogen (N) cycling performed by ammonia-oxidizing archaea (AOA) and bacteria (AOB), nitrite-oxidizing bacteria (NOB), and complete ammonia oxidation (comammox). However, the performance of these nitrifying groups in alpine grasslands has rarely been documented. This study investigated their abundance and community structure in four alpine grasslands on the Qinghai-Tibetan Plateau with quantitative PCR and high-throughput sequencing. Potential ammonia oxidation (PAO) was measured and partitioned by inhibitor method. PAO was mainly dominated by AOA. PAO and potential nitrite oxidation (PNO) significantly decreased, while the apparent half-saturation constant (Km) had no significant change along a grassland degradation gradient. Phylogenetic analyses revealed that the predominant AOA, AOB, and NOB were Nitrososphaera, Nitrosospira, and Nitrospira lineages, respectively. Network analyses revealed that the alpine nitrifying co-occurrence network had a modular structure that was mainly shaped by taxonomic relatedness and environmental relationships, indicating different nitrifying species occupy disparate niches. Soil pH, ammonium, and moisture were the main drivers for variation in AOA, AOB, and NOB communities, respectively. Here, we provide evidence of niche differentiation in nitrifying communities with changes in grassland type. Moreover, these findings support a theoretical foundation for predicting the repercussions of grassland degradation on soil nitrifying communities in alpine ecosystems. C1 [Qi, Xing-E; Wang, Chen; He, Tianjiao; Ding, Fan; Li, Aorui; Zhang, Xinfang; An, Lizhe; Xu, Shijian] Lanzhou Univ, Sch Life Sci, 222 Southern Tianshui Rd, Lanzhou 730000, Peoples R China. RP Zhang, XF (通讯作者)，Lanzhou Univ, Sch Life Sci, 222 Southern Tianshui Rd, Lanzhou 730000, Peoples R China. EM zhangxinfang@lzu.edu.cn TC 0 Z9 1 PD MAY-JUN PY 2021 VL 104 AR 103316 DI 10.1016/j.ejsobi.2021.103316 EA APR 2021 UT WOS:000649263400004 DA 2023-03-23 ER PT J AU Gao, EL Wang, YX Bi, C Kaiser-Bunbury, CN Zhao, ZG AF Gao, Erliang Wang, Yuxian Bi, Cheng Kaiser-Bunbury, Christopher N. Zhao, Zhigang TI Restoration of Degraded Alpine Meadows Improves Pollination Network Robustness and Function in the Tibetan Plateau SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Ecological restoration is widely used to mitigate the negative impacts of anthropogenic activities. There is an increasing demand to identify suitable restoration management strategies for specific habitat and disturbance types to restore interactions between organisms of degraded habitats, such as pollination. In the Tibetan Plateau, alpine meadows have suffered severe degradation due to overgrazing and climate change. Protecting vegetation by fencing during the growing season is a widely applied management regime for restoration of degraded grasslands in this region. Here, we investigated the effect of this restoration strategy on plant-pollinator communities and plant reproduction in the eastern Tibetan Plateau. We collected interaction and seed set data monthly across three grazed (grazed all year) and three ungrazed (fenced during growing season) alpine meadows in growing seasons of two consecutive years. We found ungrazed meadows produced more flowers and attracted more pollinator visits. Many common network metrics, such as nestedness, connectance, network specialization, and modularity, did not differ between grazing treatments. However, plants in ungrazed meadows were more robust to secondary species extinction than those in grazed meadows. The observed changes in the networks corresponded with higher seed set of plants that rely on pollinators for reproduction. Our results indicate that protection from grazing in growing seasons improves pollination network stability and function and thus is a viable restoration approach for degraded meadows. C1 [Gao, Erliang; Wang, Yuxian; Bi, Cheng; Zhao, Zhigang] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou, Peoples R China. [Kaiser-Bunbury, Christopher N.] Univ Exeter, Coll Life & Environm Sci, Ctr Ecol & Conservat, Penryn, Cornwall, England. RP Zhao, ZG (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou, Peoples R China. EM zhaozhg@lzu.edu.cn TC 2 Z9 2 PD APR 13 PY 2021 VL 9 AR 632961 DI 10.3389/fevo.2021.632961 UT WOS:000644156900001 DA 2023-03-23 ER PT J AU Chen, QY Yuan, YL Hu, YL Wang, J Si, GC Xu, R Zhou, JZ Xi, CW Hu, A Zhang, GX AF Chen, Qiuyu Yuan, Yanli Hu, Yilun Wang, Jian Si, Guicai Xu, Ri Zhou, Jizhong Xi, Chuanwu Hu, Ang Zhang, Gengxin TI Excessive nitrogen addition accelerates N assimilation and P utilization by enhancing organic carbon decomposition in a Tibetan alpine steppe SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB High amounts of deposited nitrogen (N) dramatically influence the stability and functions of alpine ecosystems by changing soil microbial community functions, but the mechanism is still unclear. To investigate the impacts of increased N deposition on microbial community functions, a 2-year multilevel N addition (0, 10, 20, 40, 80 and 160 kg N ha(-1) year(-1)) field experiment was set up in an alpine steppe on the Tibetan Plateau. Soil microbial functional genes (GeoChip 4.6), together with soil enzyme activity, soil organic compounds and environmental variables, were used to explore the response of microbial community functions to N additions. The results showed that the N addition rate of 40 kg N ha(-1) year(-1) was the critical value for soil microbial functional genes in this alpine steppe. A small amount of added N (<= 40 kg N ha(-1) year(-1)) had no significant effects on the abundance of microbial functional genes, while high amounts of added N (>40 kg N ha(-1) year(-1)) significantly increased the abundance of soil organic carbon degradation genes. Additionally, the abundance of microbial functional genes associated with NH4+, including ammonification, N fixation and assimilatory nitrate reduction pathways, was significantly increased under high N additions. Further, high N additions also increased soil organic phosphorus utilization, which was indicated by the increase in the abundance of phytase genes and alkaline phosphatase activity. Plant richness, soil NO2-/NH4+ and WSOC/WSON were significantly correlated with the abundance of microbial functional genes, which drove the changes in microbial community functions under N additions. These findings help us to predict that increased N deposition in the future may alter soil microbial functional structure, which will lead to changes in microbially-mediated biogeochemical dynamics in alpine steppes on the Tibetan Plateau and will have extraordinary impacts on microbial C, N and P cycles. (C) 2020 Elsevier B.V. All rights reserved. C1 [Chen, Qiuyu; Yuan, Yanli; Hu, Yilun; Xu, Ri; Zhang, Gengxin] Chinese Acad Sci, Inst Tibetan Plateau Res, CAS Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Hu, Yilun] Univ Chinese Acad Sci, Beijing 100101, Peoples R China. [Wang, Jian] China West Normal Univ, Land & Resources Coll, Nanchong 637009, Sichuan, Peoples R China. [Si, Guicai] Chinese Acad Sci, Lanzhou Ctr Oil & Gas Resources, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. [Zhou, Jizhong] Univ Oklahoma, Inst Environm Genom, Norman, OK 73019 USA. [Zhou, Jizhong] Univ Oklahoma, Dept Microbiol & Plant Biol, Norman, OK 73019 USA. [Zhou, Jizhong] Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100084, Peoples R China. [Xi, Chuanwu] Univ Michigan, Sch Publ Hlth, Dept Environm Hlth Sci, Ann Arbor, MI 48109 USA. [Hu, Ang] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Peoples R China. [Zhang, Gengxin] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. RP Zhang, GX (通讯作者)，Chinese Acad Sci, CAS Key Lab Alpine Ecol, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. EM zhangg@itpcas.ac.cn TC 16 Z9 18 PD APR 10 PY 2021 VL 764 AR 142848 DI 10.1016/j.scitotenv.2020.142848 UT WOS:000614249600045 DA 2023-03-23 ER PT J AU Wang, J Wang, XT Liu, GB Wang, GL Zhang, C AF Wang, Jie Wang, Xiangtao Liu, Guobin Wang, Guoliang Zhang, Chao TI Grazing-to-fencing conversion affects soil microbial composition, functional profiles by altering plant functional groups in a Tibetan alpine meadow SO APPLIED SOIL ECOLOGY DT Article AB Information on the effect of anthropogenic activities on soil microbial communities can improve our ability to formulate restoration strategies in the Tibetan Plateau, where meadow degradation has been an increasing concern. In this study, we evaluated plant functional groups, soil properties, microbial communities, and their functional groups in four types of meadows (grazed, fenced, fenced + reseeded, and intact) in the Tibetan Plateau. Based on amplicon sequencing data, both the bacterial and fungal composition, their potential functions and their possible drivers have been investigated. Fencing was the most effective approach to restore degraded alpine meadows, characterized by higher aboveground biomass, soil nutrient levels, and microbial diversity. The soil carbon, ammonium nitrogen, and the above- and below-ground biomass (mainly sedge and grass groups) were closely related to the changes in bacterial and fungal composition, while the diversity of sedge, grass, legumes, and forbs was largely associated with N cycling and fungal functional guilds. Grazing-to-fencing conversion also caused changes in the microbial community composition, specifically resulting in a shift from oligotrophs to copiotrophs, an increased abundance of diazotrophs and plant pathogens, and a decreased abundance of nitrifiers. Our results revealed the effects of grazing-to-fencing conversion on an alpine meadow and can provide significant guidance for the sustainable management of degraded grassland ecosystems. C1 [Wang, Jie; Liu, Guobin; Wang, Guoliang; Zhang, Chao] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Wang, Xiangtao] Xizang Agr & Anim Husb Coll, Dept Anim Sci, Linzhi 860000, Peoples R China. [Liu, Guobin] Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. RP Zhang, C (通讯作者)，Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. EM zhangchao1985@nwafu.edu.cn TC 11 Z9 11 PD OCT PY 2021 VL 166 AR 104008 DI 10.1016/j.apsoil.2021.104008 EA APR 2021 UT WOS:000679311300013 DA 2023-03-23 ER PT J AU Li, T Cui, LZ Xu, ZH Hu, RH Joshi, PK Song, XF Tang, L Xia, AQ Wang, YF Guo, D Zhu, JP Hao, YB Song, L Cui, XY AF Li, Tong Cui, Lizhen Xu, Zhihong Hu, Ronghai Joshi, Pawan K. Song, Xiufang Tang, Li Xia, Anquan Wang, Yanfen Guo, Da Zhu, Jiapei Hao, Yanbin Song, Lan Cui, Xiaoyong TI Quantitative Analysis of the Research Trends and Areas in Grassland Remote Sensing: A Scientometrics Analysis of Web of Science from 1980 to 2020 SO REMOTE SENSING DT Article AB Grassland remote sensing (GRS) is an important research topic that applies remote sensing technology to grassland ecosystems, reflects the number of grassland resources and grassland health promptly, and provides inversion information used in sustainable development management. A scientometrics analysis based on Science Citation Index-Expanded (SCI-E) was performed to understand the research trends and areas of focus in GRS research studies. A total of 2692 papers related to GRS research studies and 82,208 references published from 1980 to 2020 were selected as the research objects. A comprehensive overview of the field based on the annual documents, research areas, institutions, influential journals, core authors, and temporal trends in keywords were presented in this study. The results showed that the annual number of documents increased exponentially, and more than 100 papers were published each year since 2010. Remote sensing, environmental sciences, and ecology were the most popular Web of Science research areas. The journal Remote Sensing was one of the most popular for researchers to publish documents and shows high development and publishing potential in GRS research studies. The institution with the greatest research documents and most citations was the Chinese Academy of Sciences. Guo X.L., Hill M.J., and Zhang L. were the most productive authors across the 40-year study period in terms of the number of articles published. Seven clusters of research areas were identified that generated contributions to this topic by keyword co-occurrence analysis. We also detected 17 main future directions of GRS research studies by document co-citation analysis. Emerging or underutilized methodologies and technologies, such as unmanned aerial systems (UASs), cloud computing, and deep learning, will continue to further enhance GRS research in the process of achieving sustainable development goals. These results can help related researchers better understand the past and future of GRS research studies. C1 [Li, Tong; Hu, Ronghai; Tang, Li; Guo, Da] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Li, Tong; Xu, Zhihong; Tang, Li] Griffith Univ, Sch Environm & Sci, Brisbane, Qld 4111, Australia. [Li, Tong; Cui, Lizhen; Hu, Ronghai; Tang, Li; Xia, Anquan; Wang, Yanfen; Zhu, Jiapei; Hao, Yanbin; Cui, Xiaoyong] Chinese Acad Sci, Yanshan Earth Crit Zone & Surface Fluxes Res Stn, Beijing 100049, Peoples R China. [Cui, Lizhen; Xia, Anquan; Wang, Yanfen; Hao, Yanbin; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Joshi, Pawan K.] Jawaharlal Nehru Univ, Sch Environm Sci, Special Ctr Disaster Res, New Delhi 110067, India. [Song, Xiufang] Chinese Acad Sci, Natl Sci Lib, Beijing 100190, Peoples R China. [Wang, Yanfen; Hao, Yanbin; Cui, Xiaoyong] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhu, Jiapei] Univ Chinese Acad Sci, Sino Danish Coll, Beijing 100049, Peoples R China. [Song, Lan] Southern Univ Sci & Technol, Sch Environm Sci & Engn, Shenzhen 518055, Peoples R China. RP Cui, XY (通讯作者)，Chinese Acad Sci, Yanshan Earth Crit Zone & Surface Fluxes Res Stn, Beijing 100049, Peoples R China.; Cui, XY (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China.; Cui, XY (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. EM tong.li7@griffithuni.edu.au; cuilizhen18@mails.ucas.ac.cn; zhihong.xu@griffith.edu.au; huronghai@ucas.ac.cn; pkjoshi@mail.jnu.ac.in; songxf@mail.las.ac.cn; tangli@ucas.ac.cn; xiaanquan17@mails.ucas.ac.cn; yfwang@ucas.ac.cn; guoda181@mails.ucas.ac.cn; zhujiapei18@mails.ucas.ac.cn; ybhao@ucas.ac.cn; songlan@sustech.edu.cn; cuixy@ucas.ac.cn TC 15 Z9 15 PD APR PY 2021 VL 13 IS 7 AR 1279 DI 10.3390/rs13071279 UT WOS:000638788200001 DA 2023-03-23 ER PT J AU Qi, L Qiao, YS Liu, ZX Peng, SS Cheng, Y Wang, Y Zhang, XJ Tian, MZ Yang, SB Bai, WB AF Qi Lin Qiao Yan-song Liu Zong-xiu Peng Sha-sha Cheng Yu Wang Yan Zhang Xu-jiao Tian Ming-zhong Yang Shuai-bin Bai Wen-bin TI Carbon isotope variations of modern soils in the eastern margin of the Tibetan Plateau and their controlling factors SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB The marginal areas of the Tibetan Plateau have great vertical altitude gradient and abundant vegetation, they are therefore the ideal places for investigating the relationships among carbon isotope composition (delta C-13) of modern soils, vegetation and environmental factors, which would be very useful for the reconstructions of both paleovegetation and paleoclimate. In this paper, modern soil samples collected in different vegetation vertical zones along 4 km elevation gradient in the eastern margin of the Tibetan Plateau were analyzed for their carbon isotope composition. The results show that the modern soils in different vegetation vertical zones show apparent difference of delta C-13 values, which get heavier in the sequence of mixed evergreen and deciduous broad-leaved forest (-27.28 parts per thousand on average), evergreen broad-leaved forest (-27.25 parts per thousand), subalpine shrub-meadow (-25.81 parts per thousand), subalpine coniferous forest (-25.81 parts per thousand), alpine bush-meadow (-25.16 parts per thousand), and drought-enduring shrub (-24.07 parts per thousand). 1800 m and 3500 m are two critical points for the delta C-13 values with respect to altitude. Specifically, the delta C-13 values decrease with increasing altitude below both points while increasing with increasing altitude above both points. Further analyses indicate that the declining delta C-13 values are mainly controlled by the decreasing proportion of C-4 plants with elevation and the increasing delta C-13 values are attributed to the plant physic-morphological adaptation to the alpine environment. In the absence of drought stress, temperature is the main controlling factor for the carbon isotopic variations with altitude gradient. C1 [Qi Lin; Qiao Yan-song; Liu Zong-xiu] Chinese Acad Geol Sci, Key Lab Neotecton Movement & Geohazard, Beijing 100081, Peoples R China. [Qi Lin; Qiao Yan-song; Liu Zong-xiu; Wang Yan; Yang Shuai-bin] Chinese Acad Geol Sci, Inst Geomech, Beijing 100081, Peoples R China. [Peng Sha-sha] Chinese Acad Sci, Guangzhou Inst Geochem, Guangzhou 510640, Peoples R China. [Cheng Yu] Inst Geol Survey Jiangsu Prov, Nanjing 210018, Peoples R China. [Zhang Xu-jiao; Tian Ming-zhong; Bai Wen-bin] China Univ Geosci, Sch Earth Sci & Resources, Beijing 100083, Peoples R China. RP Qiao, YS (通讯作者)，Chinese Acad Geol Sci, Key Lab Neotecton Movement & Geohazard, Beijing 100081, Peoples R China.; Qiao, YS (通讯作者)，Chinese Acad Geol Sci, Inst Geomech, Beijing 100081, Peoples R China. EM liuyingqilin@sina.com; yansongqiao66@163.com; tqwanliu@sina.com; pengsh@gig.ac.cn; ftchengyu@msn.com; wy6916@sina.com; zhangxj@cugb.edu.cn; tianmz@cugb.edu.cn; yangshuaibin1992@163.com; baibaoking@163.com TC 0 Z9 0 PD APR PY 2021 VL 18 IS 4 BP 878 EP 890 DI 10.1007/s11629-019-5863-3 UT WOS:000639495600005 DA 2023-03-23 ER PT J AU Tang, LY Chen, L Yang, ZA AF Tang, Liuyan Chen, Lin Yang, Zhen'an TI Artificial Measures Are Not Necessarily Better Than Natural Recovery for the Extremely Degraded Alpine Meadow: The Results of Simulated Degradation Restoration After Three Years SO JOURNAL OF BIOBASED MATERIALS AND BIOENERGY DT Article AB Natural and artificial restoration measures are widely used to restore degraded ecosystems, such as degraded alpine meadow. The objective of this research was to evaluate the advantages and disadvantages of natural and artificial measures for extremely degraded alpine meadows. We removed the surface soil (0-10 cm) of the alpine meadow to simulate the extremely degraded "black soil beach," and set artificial measures (planting Festuca sinensis (E) and Elymus sibircus L. cv. chuancao No. 1 (F)) and natural recovery (N) ( without any artificial auxiliary measures) in the northeastern part of the Qinghai-Tibet Plateau (QTP), China. After 3 years, we determined the characteristics of community and soil in the artificial and natural treatment. The results show that the species number, above-and below-ground biomass (AB, BB), root-shoot ratio (R/S) in N is significantly higher than that in artificial restoration (E and F); while the community coverage and concentration of soil total carbon, total nitrogen, microbial biomass carbon, microbial biomass nitrogen and microbial biomass phosphorus (TC, TN, MBC, MBN and MBP) in artificial restoration is significantly higher than that in N. In conclusion, compared with N, artificial measures (E and F) are not completely beneficial to the development of plant community diversity and the restoration of soil nutrients in the extremely degraded meadow. Thus, the establishment of artificial grassland is not necessarily better than natural recovery for the extremely degraded alpine meadow. C1 [Tang, Liuyan; Chen, Lin; Yang, Zhen'an] China West Normal Univ, Minist Educ, Key Lab Southwest China Wildlife Resources Conser, Nanchong 637009, Sichuan, Peoples R China. RP Yang, ZA (通讯作者)，China West Normal Univ, Minist Educ, Key Lab Southwest China Wildlife Resources Conser, Nanchong 637009, Sichuan, Peoples R China. EM yza2765@126.com TC 1 Z9 1 PD APR PY 2021 VL 15 IS 2 BP 224 EP 230 DI 10.1166/jbmb.2021.2041 UT WOS:000658255600012 DA 2023-03-23 ER PT J AU Zhang, JG Liu, DW Meng, BP Chen, JJ Wang, XY Jiang, H Yu, Y Yi, SH AF Zhang, Jianguo Liu, Dawei Meng, Baoping Chen, Jianjun Wang, Xiaoyun Jiang, Hui Yu, Yue Yi, Shuhua TI Using UAVs to assess the relationship between alpine meadow bare patches and disturbance by pikas in the source region of Yellow River on the Qinghai-Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Degradation of the alpine meadow has received increasing attention recently, and plateau pika (Ochotona curzoniae, hereafter pika) disturbance is considered as an important cause. Bare patches are the most obvious features indicating the degree of degradation. Previous studies mainly focus on bare patches' overall status, i.e., the fractional bare patches (or fractional vegetation cover). However, our understanding of individual bare patches' change rates and their relationship with pika disturbances is insufficient. In this study, aerial photos were taken by an unmanned aerial vehicle (UAV) within a typical alpine meadow ecosystem, over four monitoring sites with different area fraction of bare patches: almost no bare patches (NBP, < 5%), low bare patches (LBP, 5% -20%), moderate bare patches (MBP, 20% -60%) and high bare patches (HBP, > 60%) during 2015 and 2018. The relationship between the changes of pika disturbances and bare patches were analyzed based on these aerial photos. Results showed that: 1) changes of pika holes and bare patches were not significant (P > 0.05) at MBP and HBP, while they increased significantly (P < 0.05) at NBP, which suggested that the increase of bare patches could be ascribed to increase of pika holes. However, both pika holes and bare patches almost disappeared at LBP in three years, implying a high resilience of this site; 2) the differences in correlations between the pika hole density and the area fraction of bare patches were remarkable among different sites. Specifically, there were significant linear correlation at NBP (y = 642.01x + 506.52, R-2 = 0.91; P < 0.05) and HBP (y =-29.036x + 2983.9, R-2 = 0.72, P < 0.01), and a significant negative correlation in exponential form at MBP (y = 2632.3e-0.022x, R-2 = 0.50, P < 0.05), while no significant correlation was observed between the two at LBP. We concluded that the changes in bare patches and their relationship with pika disturbances were diverse over a short period. Therefore, long-term repeated aerial photographing over grasslands at different stages of degradation is required for further research, and UAV is a feasible tool to fulfill the task. (C) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). C1 [Zhang, Jianguo; Liu, Dawei; Meng, Baoping; Jiang, Hui; Yu, Yue; Yi, Shuhua] Nantong Univ, Sch Geog Sci, Inst Fragile Ecosyst & Environm, 999 Tongjing Rd, Nantong 226007, Jiangsu, Peoples R China. [Chen, Jianjun] Guilin Univ Technol, Coll Geomat & Geoinformat, 12 Jiangan St, Guilin 541006, Peoples R China. [Wang, Xiaoyun] Lanzhou Univ, Coll Earth & Environm Sci, Minist Educ, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Peoples R China. RP Yi, SH (通讯作者)，Nantong Univ, Sch Geog Sci, Inst Fragile Ecosyst & Environm, 999 Tongjing Rd, Nantong 226007, Jiangsu, Peoples R China. EM yis@ntu.edu.cn TC 9 Z9 12 PD APR PY 2021 VL 26 AR e01517 DI 10.1016/j.gecco.2021.e01517 UT WOS:000641411400001 DA 2023-03-23 ER PT J AU Qian, DW Du, YG Li, Q Guo, XW Cao, GM AF Qian, Dawen Du, Yangong Li, Qian Guo, Xiaowei Cao, Guangmin TI Alpine grassland management based on ecosystem service relationships on the southern slopes of the Qilian Mountains, China SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Grassland management is one of the most important means to address grassland degradation on the QinghaiTibet Plateau, but at present, the primary goal is still to improve grassland productivity, and little research has been conducted on grassland management based on its ecosystem service relationships. Based on remote sensing and meteorological data, we calculated and analyzed the spatial and temporal changes, trade-offs and synergistic relationships between livestock production and water retention services in alpine grassland on the southern slopes of the Qilian Mountains (SSQM), and designed a grazing management plan for sustainable development in the region. The results showed that the value of livestock production and water retention services of alpine grassland decreased from east to west, and their relationship is dominated by synergy and complemented by trade-offs. The synergistic relationships are concentrated in the Qinghai Lake Basin in the south and the river valleys in the north, while the trade-offs are scattered in the steeper terrain in the western and eastern parts of the study area. The scenario of preserving all water retention services and losing some livestock production services is sustainable. Based on this scenario we divided the alpine grassland of the study area into maintenance grazing, rotational grazing and grazing exclusion of 65.8%, 32.0% and 2.2%, respectively. Our study demonstrates that ecosystem service relationships have the potential to guide grassland management, and the results will provide new approaches to alpine grassland management. C1 [Qian, Dawen; Du, Yangong; Li, Qian; Guo, Xiaowei; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, Xining, Qinghai, Peoples R China. RP Qian, DW (通讯作者)，23 Xinning Rd, Xining 810008, Qinghai, Peoples R China. EM dwqian@nwipb.cas.cn; ygdu@nwipb.cas.cn; liqian@nwipb.cas.cn; guoxw@nwipb.cas.cn; caogm@nwipb.cas.cn TC 11 Z9 12 PD JUN 15 PY 2021 VL 288 AR 112447 DI 10.1016/j.jenvman.2021.112447 EA MAR 2021 UT WOS:000643642500004 DA 2023-03-23 ER PT J AU Wu, GL Li, XL Gao, J AF Wu, Guiling Li, Xilai Gao, Jay TI The evolution of hummock-depression micro-topography in an alpine marshy wetland in Sanjiangyuan as inferred from vegetation and soil characteristics SO ECOLOGY AND EVOLUTION DT Article AB The hummock-depression micro-topography characteristics of the alpine marshy wetland in Sanjiangyuan are indicative of wetland degradation and the process by which healthy wetlands are transformed into flat grasslands. The aim of the present study was to examine changes in plant community structure and soil characteristics in a hummock-depression micro-topography along a degradation gradient. We observed that: (a) the height and cover of dominant hydrophytes decreased gradually with an increase in degradation severity, leading to replacement by xerophytes; (b) with the transition from healthy to degraded wetlands, hummocks became sparser, shorter, and broader and became merged with nearby depressions; water reserves in the depressions shifted from perennial to seasonal, until they dried out completely; and (c) soil moisture content, porosity, hardness, and organic matter gradually decreased by 30.61%, 19.06%, 37.04%, and 73.27%, respectively, in hummocks and by 33.25%, 8.19%, 47.72%, and 76.79%, respectively, in depressions. Soil bulk density, soil electrical conductivity, and soil dry weight increased by 31%, 83.33%, and 105.44%, respectively, in hummocks, but by only 11.93%, 7.14%, and 97.72%, respectively, in depressions. The results show that hummock soils in healthy wetlands have strong water absorption properties, through which plant roots can penetrate easily. Wetland degradation reduces the water absorption capacity of hummock soil and soil saturation capacity of depressions, thus enhancing soil erosion potential and susceptibility to external factors. Soil moisture is a key environmental factor influencing wetland degradation, and grazing accelerates the process. Based on the changes observed in hummock morphology, vegetation, and soil properties along a degradation gradient, a conceptual model is proposed to illustrate the process of gradual degradation of marshy wetlands from healthy to transitional wetlands and finally to a degenerated state. Thus, our research provides insights into the degradation process of the alpine marshy wetland ecosystem in Sanjiangyuan. C1 [Wu, Guiling; Li, Xilai] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Wu, Guiling; Li, Xilai] Qinghai Univ, Coll Agr & Anim Husb, Xining, Peoples R China. [Gao, Jay] Univ Auckland, Sch Environm, Auckland, New Zealand. RP Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China.; Gao, J (通讯作者)，Univ Auckland, Sch Environm, Auckland, New Zealand. EM xilai-li@163.com; jg.gao@auckland.ac.nz TC 3 Z9 3 PD MAY PY 2021 VL 11 IS 9 BP 3901 EP 3916 DI 10.1002/ece3.7278 EA MAR 2021 UT WOS:000632675600001 DA 2023-03-23 ER PT J AU Zhuang, MH Lu, X Peng, W Wang, YF Wang, JX Nielsen, CP McElroy, MB AF Zhuang, Minghao Lu, Xi Peng, Wei Wang, Yanfen Wang, Jianxiao Nielsen, Chris P. McElroy, Michael B. TI Opportunities for household energy on the Qinghai-Tibet Plateau in line with United Nations' Sustainable Development Goals SO RENEWABLE & SUSTAINABLE ENERGY REVIEWS DT Article AB Approximately seven million population in the Qinghai-Tibet Plateau of China, a global climate sensitive region, still rely primarily on yak dung for household cooking and heating. The treatment and combustion of yak dung result in a variety of negative impacts in terms of local alpine grassland degradation, indoor air pollution, public health risk, as well as global climate change. There is an urgent need to explore alternative pathway for affordable and clean energy as indicated in the United Nations' Sustainable Development Goals for 2030. This perspective has analyzed the key challenges rooted in yak dung use on the Qinghai-Tibet Plateau region. Based on this, this perspective has further proposed a new complementary energy system to take advantage of locally available, clean and sustainable energy sources of wind and solar power, and have provided economic analyses. Meanwhile, this perspective has pointed out the potential barriers to promoting the new complementary energy system in the Qinghai-Tibet Plateau region due to traditional habits, economic factors and policies. Finally, strategies for transitioning from yak dung to the proposed alternative energy system is discussed at the end. Successful energy transition for the Qinghai-Tibet Plateau region offers an important option to achieving many other sustainable development goals related to climate change, economic development, and environment. The perspective is expected to shed light on the development of sustainable energy in other developing region or countries in the world to address multiple societal goals. C1 [Zhuang, Minghao; Lu, Xi] Tsinghua Univ, State Key Joint Lab Environm Simulat & Pollut Con, Sch Environm, Beijing, Peoples R China. [Zhuang, Minghao] China Agr Univ, Natl Acad Agr Green Dev, Coll Resources & Environm Sci, Key Lab Plant Soil Interact MOE, Beijing, Peoples R China. [Peng, Wei] Penn State Univ, Sch Int Affairs, University Pk, PA 16802 USA. [Peng, Wei] Penn State Univ, Dept Civil & Environm Engn, University Pk, PA 16802 USA. [Wang, Yanfen] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Wang, Yanfen] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Wang, Jianxiao] North China Elect Power Univ, Sch Elect & Elect Engn, Beijing, Peoples R China. [Nielsen, Chris P.; McElroy, Michael B.] Harvard Univ, Harvard John A Paulson Sch Engn & Appl Sci, Cambridge, MA 02138 USA. [McElroy, Michael B.] Harvard Univ, Dept Earth & Planetary Sci, 20 Oxford St, Cambridge, MA 02138 USA. RP Lu, X (通讯作者)，Tsinghua Univ, State Key Joint Lab Environm Simulat & Pollut Con, Sch Environm, Beijing, Peoples R China.; Wang, YF (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China.; Wang, YF (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. EM xilu@tsinghua.edu.cn; yfwang@ucas.ac.cn TC 4 Z9 4 PD JUL PY 2021 VL 144 AR 110982 DI 10.1016/j.rser.2021.110982 EA MAR 2021 UT WOS:000648860000005 DA 2023-03-23 ER PT J AU Wang, LY Jiang, GL Fu, ZT Liu, YL Gao, SR Zhao, HT Wu, QB AF Wang, Luyang Jiang, Guanli Fu, Ziteng Liu, Yali Gao, Siru Zhao, Hongting Wu, Qingbai TI A Study on the Hydrothermal Regime of Aeolian Sand and the Underlying Soil in the Frozen Soil Zone on the Qinghai-Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB The hydrothermal process within the aeolian sand layer on the Qinghai-Tibetan Plateau (QTP) plays a key role in understanding the interaction between desertification and underlying frozen soil. However, little is known about the hydrothermal dynamics of aeolian sand and underling soil layer in the frozen soil zone on the QTP. In this study, a sparse vegetation cover site and three aeolian sand cover sites with different sand thicknesses were established to study the hydrothermal dynamics within aeolian sand layer. The results show that the thickness of aeolian sand is critical in the soil hydrothermal process under sand cover. The increase in thickness of the aeolian sand layer resulted in an advance in the onset of the freezing and thawing of soil, and accelerated movement of the freezing and thawing front. In addition, the increase in sand thickness caused an increase in soil temperature during the thawing stage and the warming period of the thawed stage, whereas a decrease occurred during the cooling period of the thawed stage, the freezing stage and the frozen stage, which ultimately caused the enlargement of the annual range of ground temperature. Furthermore, in the study area, the actual evapotranspiration of sand-covered surface was larger than that of the naked surface. The water content also decreased with increasing sand thickness in different stages, which separately decreased the heat budget in both the warm and cold season because of the smaller thermal conductivity of aeolian sand with a lower water content. This study states that through the special hydrothermal process, have an adverse impact on the occurrence and formation of the frozen soil in the QTP. C1 [Wang, Luyang; Jiang, Guanli; Fu, Ziteng; Liu, Yali; Gao, Siru; Zhao, Hongting; Wu, Qingbai] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. [Wang, Luyang; Fu, Ziteng; Liu, Yali; Zhao, Hongting; Wu, Qingbai] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Luyang; Jiang, Guanli; Gao, Siru; Wu, Qingbai] Chinese Acad Sci, Beiluhe Observat Stn Frozen Soil Environm & Engn, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. RP Wu, QB (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, 320 West Donggang Rd, Lanzhou 730000, Peoples R China. EM wangluyang@nieer.ac.cn; atos@lzb.ac.cn; fuziteng@lzh.ac.cn; liuyali@lzb.ac.cn; gaosiru@lzb.ac.cn; zhaohongting@lzb.zc.cn; qbwu@lzb.ac.cn TC 4 Z9 4 PD MAR 15 PY 2021 VL 298 AR 108294 DI 10.1016/j.agrformet.2020.108294 UT WOS:000610797100016 DA 2023-03-23 ER PT J AU Li, CY Peng, F Lai, CM Xue, X You, QG Chen, XJ Liao, J Ma, SX Wang, T AF Li, Chengyang Peng, Fei Lai, Chimin Xue, Xian You, Quangang Chen, Xiaojie Liao, Jie Ma, Shaoxiu Wang, Tao TI Plant community changes determine the vegetation and soil delta C-13 and delta N-15 enrichment in degraded alpine grassland SO LAND DEGRADATION & DEVELOPMENT DT Article AB delta C-13 and delta N-15 are extensively used to understand the biogeochemical mechanisms that moderate ecosystem carbon (C) and nitrogen (N) processes. Little is known about the responses of delta C-13 and delta N-15 to alpine grassland degradation on the Qinghai-Tibetan Plateau (QTP), which prevents a full understanding of degradation-induced changes in C and N cycling there. We investigated the vegetation delta C-13 and delta N-15, soil delta C-13 and delta N-15, soil properties, and plant community composition of alpine grassland on the QTP that were in different states of degradation. Our results show that the vegetation delta C-13 and delta N-15, and soil delta C-13 and delta N-15, increased with the severity of degradation, whereas soil organic carbon (SOC) and total N content decreased as degradation became more severe. The aboveground biomass percentage of forbs was positively correlated with the soil C/N ratio, vegetation delta C-13, and soil delta C-13, and accounted for the largest proportion of the variance for both vegetation delta C-13 and soil delta C-13 (17.25 and 23.65%, respectively). The vegetation delta N-15 and soil delta N-15 were negatively correlated with the soil C/N ratio, which explained the largest proportion of the variance (18.01 and 25.81%, respectively). Our results suggest that C cycling is strongly moderated by plant community composition, because forbs species and C-4 species, were more prevalent in degraded alpine grassland. Meanwhile, N cycling is indirectly regulated by changes in community composition via its effect on the soil C/N as the degradation became more severe for alpine grassland on the QTP. C1 [Li, Chengyang; Peng, Fei; Lai, Chimin; Xue, Xian; You, Quangang; Chen, Xiaojie; Liao, Jie; Ma, Shaoxiu; Wang, Tao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. [Li, Chengyang; Lai, Chimin] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Peng, Fei] Int Platform Dryland Res & Educ, Tottori, Japan. [Peng, Fei] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Lanzhou, Peoples R China. RP Peng, F (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. EM pengfei@lzb.ac.cn TC 7 Z9 8 PD APR 30 PY 2021 VL 32 IS 7 BP 2371 EP 2382 DI 10.1002/ldr.3912 EA MAR 2021 UT WOS:000626534700001 DA 2023-03-23 ER PT J AU Li, M Wu, JS Feng, YF Niu, B He, YT Zhang, XZ AF Li, Meng Wu, Jianshuang Feng, Yunfei Niu, Ben He, Yongtao Zhang, Xianzhou TI Climate Variability Rather Than Livestock Grazing Dominates Changes in Alpine Grassland Productivity Across Tibet SO FRONTIERS IN ECOLOGY AND EVOLUTION DT Article AB Alpine grasslands on the Tibetan Plateau, being vulnerable to environmental and anthropogenic changes, have experienced dramatic climate change and intensive livestock grazing during the last half-century. Climate change, coupled with grazing activities, has profoundly altered alpine grassland function and structure and resulted in vast grassland degradation. To restore degraded grasslands, the Central Government of China has implemented the Ecological Security Barrier Protection and Construction Project since 2008 across the Tibetan Autonomous Region. However, the relative effect of climate change and grazing activities on the variation in alpine grassland productivity is still under debate. In this study, we quantified how aboveground net primary production (ANPP) varied before (2000-2008) and after (2009-2017) starting the project across different alpine grasslands and how much variance in ANPP could be attributed to climate change and grazing disturbance, in terms of temperature, precipitation, solar radiation, and grazing intensity. Our results revealed that Tibet's climate got warmer and wetter, and grazing intensity decreased after starting the project. Mean ANPP increased at approximately 81% of the sites, on average from 27.0 g C m(-2) during 2000-2008 to 28.4 g C m(-2) during 2009-2017. The ANPP positively correlated with annual temperature and precipitation, but negatively with grazing intensity for both periods. Random forest modeling indicated that grazing intensity (14.5%) had a much lower influence in controlling the dynamics of grassland ANPP than precipitation (29.0%), suggesting that precipitation variability was the key factor for alpine grassland ANPP increase across Tibet. C1 [Li, Meng] Nantong Univ, Sch Geog Sci, Nantong, Peoples R China. [Wu, Jianshuang] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. [Wu, Jianshuang] Free Univ Berlin, Theoret Ecol, Inst Biol, Berlin, Germany. [Feng, Yunfei] Tangshan Normal Univ, Dept Resource Management, Tangshan, Peoples R China. [Niu, Ben; He, Yongtao; Zhang, Xianzhou] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Natl Ecol Res Stn, Key Lab Ecosyst Network Observat & Modelling, Beijing, Peoples R China. RP Wu, JS (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China.; Wu, JS (通讯作者)，Free Univ Berlin, Theoret Ecol, Inst Biol, Berlin, Germany. EM wujianshuang@caas.cn TC 12 Z9 12 PD MAR 8 PY 2021 VL 9 AR 631024 DI 10.3389/fevo.2021.631024 UT WOS:000631067900001 DA 2023-03-23 ER PT J AU Cao, JJ Wei, C Adamowski, JF Biswas, A Li, YM Zhu, GF Liu, CF Feng, Q AF Cao, Jianjun Wei, Chen Adamowski, Jan F. Biswas, Asim Li, Yumei Zhu, Guofeng Liu, Chunfang Feng, Qi TI On China's Qinghai-Tibetan Plateau, duration of grazing exclosure alters R: S ratio, root morphology and attending root biomass SO SOIL & TILLAGE RESEARCH DT Article AB Unsustainable human actions and climate change have threatened global grasslands and lead to biodiversity loss and compromised ecosystem functions. Widely considered to be an effective approach to restore degraded grasslands, grazing exclosure (GE) likely affects biomass allocation and root morphology in the long-term, although their impacts are yet to be documented. The objective of this study was to investigate the effects of grazing exclosure durations of 5, 22, and 39 years (GE(5), GE(22), GE(39), respectively) on root:shoot biomass allocation (R:S ratio) and root morphology ? including root average diameter (RAD), root density (RD), specific root length (SRL), specific root area (SRA), and root length density (RLD) - in an alpine grassland on the Qinghai Tibetan Plateau. Seasonal grazing (SG) land served as a control. In the 0-0.30 m soil layer, the R:S ratios of the SG (1.27) and GE(5) sites (0.90) were significantly lower than that of the GE(39) site (2.14). However, there was no difference between the GE(22) (1.83) and GE(39) sites. The R:S ratio of the 0-0.15 m soil layer showed an increasing trend with duration of grazing exclosure and had a significantly greater value under GE(39) (1.89) than under GE(5) (0.76). However, the R:S ratios for the 0.15-0.30 m soil layer (0.14, 0.28 and 0.25 for GE(5), GE(22), and GE(39), respectively) showed no significant changes with grazing exclosure duration. In the 0-0.30 m soil layer across sampled sites, RAD remained constant, RD and RLD exhibited an increasing trend, while SRA and SRL displayed a slightly decreasing trend with grazing exclosure duration. Below-ground biomass (BGB) was most strongly related to RLD across all sites; to RD and RLD at the GE(5) and GE(22) sites, and to RAD and RLD at the GE(39) site. Both R:S ratio and root morphology were mainly influenced by soil nitrate nitrogen. Although long-term grazing exclosure enhanced BGB and R:S ratio, soil nutrients declined with increasing exclosure duration. Therefore, to achieve improved ecosystem functions, grazing exclosure should be used with caution in this area or other similar regions around the world. C1 [Cao, Jianjun; Wei, Chen; Li, Yumei; Zhu, Guofeng; Liu, Chunfang] Northwest Normal Univ, Coll Geog & Environm Sci, Lanzhou 730070, Peoples R China. [Cao, Jianjun] Northwest Normal Univ, Minist Educ, Key Lab Ecofunct Polymer Mat, Lanzhou 730070, Peoples R China. [Adamowski, Jan F.] McGill Univ, Fac Agr & Environm Sci, Dept Bioresource Engn, Ste Anne De Bellevue, PQ H9X 3V9, Canada. [Biswas, Asim] Univ Guelph, Sch Environm Sci, 50 Stone Rd East, Guelph, ON N1G 2W1, Canada. [Liu, Chunfang] Gansu Engn Res Centerof Land Utilizat & Comprehen, Lanzhou 730070, Peoples R China. [Feng, Qi] Chinese Acad Sci, Cold & Arid Reg Environm Engn Res Inst, Alashan Desert Ecohydrol Expt Res Stn, Key Lab Ecohydrol Inland River Basin, Lanzhou 73000, Peoples R China. RP Feng, Q (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm Engn Res Inst, Alashan Desert Ecohydrol Expt Res Stn, Key Lab Ecohydrol Inland River Basin, Lanzhou 73000, Peoples R China. EM qifeng@lzb.ac.cn TC 6 Z9 6 PD MAY PY 2021 VL 209 AR 104969 DI 10.1016/j.still.2021.104969 EA MAR 2021 UT WOS:000630768900001 DA 2023-03-23 ER PT J AU Han, S Meng, QK Liu, HC Peng, Y Han, JP Jin, SH Fan, SX Xin, BC He, LL Li, H AF Han, Shuai Meng, Qingkai Liu, Haocheng Peng, Ying Han, Jianping Jin, Shenghong Fan, Shixiong Xin, Bingchang He, Lili Li, Hao TI Refined land-cover classification mapping using a multi-scale transformation method from remote sensing, unmanned aerial vehicle, and field surveys in Sanjiangyuan National Park, China SO JOURNAL OF APPLIED REMOTE SENSING DT Article AB Mapping the refined land-cover classification mapping (RLCM) is a primary and essential strategy for evaluating the ecological change and understanding the ecosystem services. A common problem during the generation of RLCMis a scale mismatch between remote sensing (RS) data and field quadrat, which leads to inaccuracy of the classification result. A multi-scale transformation method was developed via integrating RS, unmanned aerial vehicle (UAV), and field surveys in Sanjiangyuan National Park (SNP). With the help of UAV, a large number of virtual biomass quadrats were resampled and interpolated, and the quantitative thresholds of different vegetation coverage in alpine meadow and steppe were determined to improve land-cover classification accuracy. Based on the spatial- temporal analysis of RLCM from 1990 to 2017, the whole ecological coverage was becoming better, and its driving factor was attributed to government policy and climate change. This study can provide a practical suggestion for the management and sustainable development in SNP. (C) 2021 Society of Photo-Optical Instrumentation Engineers (SPIE) C1 [Han, Shuai; Meng, Qingkai; Liu, Haocheng] Qinghai Univ, Sch Water Resources & Elect Power, Xining, Peoples R China. [Meng, Qingkai] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Peng, Ying] Chengdu Univ Technol, Coll Nucl Technol & Automat Engn, Chengdu, Peoples R China. [Han, Jianping; Jin, Shenghong; Xin, Bingchang] Prov Geomat Informat Ctr Qinghai, Xining, Peoples R China. [Fan, Shixiong] Yellow River Conservancy Commiss, Bur Hydrol & Water Resources Survey Xining, Xining, Peoples R China. [He, Lili] Qinghai Shangzhi Technol Co Ltd, Xining, Peoples R China. [Li, Hao] Shandong Jiankan Grp Co Ltd, Jinan, Peoples R China. RP Meng, QK (通讯作者)，Qinghai Univ, Sch Water Resources & Elect Power, Xining, Peoples R China.; Meng, QK (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. EM mengqk@qhu.edu.cn TC 2 Z9 2 PD MAR 2 PY 2021 VL 15 IS 1 AR 014513 DI 10.1117/1.JRS.15.014513 UT WOS:000628757100001 DA 2023-03-23 ER PT J AU Du, CJ Gao, YH AF Du, Chenjun Gao, Yongheng TI Grazing exclusion alters ecological stoichiometry of plant and soil in degraded alpine grassland SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Grazing exclusion is one of the most effective practices to recover the degraded alpine grasslands in Tibetan Plateau. In addition, ecological stoichiometry serves as a key regulator of ecosystem function and is also closely related to nutrient process. However, knowledge about the plant-soil interactions of stoichiometry throughout the growing season is still poorly understood. In this study, we examined how grazing exclusion affected the change of C-N-P stoichiometry of plant-soil by carrying out monthly sampling in three sites. The sites were: 9 years grazing exclusion, GE9; 5 years grazing exclusion, GE5; and free grazing, FG in degraded alpine meadow. Plant and soil samples were collected five times during the growing season (May-September) to analyze plant biomass and ecological stoichiometry. Across plots, profound fencing changed plant biomass and ecological stoichiometry. Specifically, increases in green, litter and root biomass were observed under grazing exclusion. Fencing increased plant C content, C:N, C:P, N:P ratios but declined N and P contents. In contrast to the plant, there was an increasing concentrations of soil C, N and P. Our study highlighted, under grazing exclusion, grasslands advanced soil C not only by greater biomass input but also higher plant C content. Greater soil N was mainly fixed by plant production, while enhancement of soil P was mainly due to plant production recovery to stop water erosion. With a continuous improvement of nutrient pools under short-term (< 9 years) grazing exclusion, our results showed that a long-term fencing practice effect ought to be monitored to recovery degraded alpine grassland. These findings also indicated that ecological stoichiometry provides a new insight for better understanding of the mechanisms of grazing exclusion effects on nutrient process. C1 [Du, Chenjun] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Du, Chenjun] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Chengdu Inst Biol, CAS Key Lab Mt Ecol Restorat & Bioresource Utiliz, Chengdu 610041, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat & Biodivers Conservat Key Lab Sichu, Chengdu 610041, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. RP Gao, YH (通讯作者)，9 South Renmin Rd, Chengdu 610041, Peoples R China. EM gaoyh@cib.cas.cn TC 15 Z9 18 PD MAR 1 PY 2021 VL 308 AR 107256 DI 10.1016/j.agee.2020.107256 UT WOS:000604619300004 DA 2023-03-23 ER PT J AU Lin, CY Li, XL Zhang, J Sun, HF Zhang, J Han, HB Wang, QH Ma, CB Li, CY Zhang, YX Ma, XQ AF Lin, Chun-ying Li, Xi-lai Zhang, Jing Sun, Hua-fang Zhang, Juan Han, Hui-bang Wang, Qi-hua Ma, Chen-biao Li, Cheng-yi Zhang, Yu-xing Ma, Xue-qian TI Effects of degradation succession of alpine wetland on soil organic carbon and total nitrogen in the Yellow River source zone, west China SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Wetland is important carbon pools, and the degradation of wetlands causes the loss of organic carbon and total nitrogen. This study aims to explore how wetland degradation succession affects soil organic carbon (SOC) and total nitrogen (TN) contents in alpine wetland. A field survey of 180 soilsampling profiles was conducted in an alpine wetland that has been classified into three degradation succession stages. The SOC and TN contents of soil layers from 0 to 200 cm depth were studied, including their distribution characteristics and the relationship between soil water content (SWC) and microtopography. The results showed that SOC and TN of different degradation succession gradients followed the ranked order of Non Degradation (ND) > Light Degradation (LD) > Heavy Degradation (HD). SWC was positively correlated with SOC and TN (p<0.05). As the degree of degradation succession worsened, SOC and TN became more sensitive to the SWC. Microtopography was closely related to the degree of wetland degradation succession, SWC, SOC and TN, especially in the topsoil (0-30 cm). This result showed that SWC was an important indicator of SOC/TN in alpine wetland. It is highly recommended to strengthen water injection into the wetland as a means of effective restoration to reverse alpine meadow back to marsh alpine wetland. C1 [Lin, Chun-ying; Li, Xi-lai] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Lin, Chun-ying; Han, Hui-bang; Wang, Qi-hua; Zhang, Yu-xing; Ma, Xue-qian] Qinghai Prov Weather Modificat Off, Xining 810001, Peoples R China. [Lin, Chun-ying; Li, Xi-lai; Zhang, Jing; Sun, Hua-fang; Li, Cheng-yi] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Zhang, Juan] Meteorol Inst Qinghai Prov, Xining 810001, Peoples R China. [Ma, Chen-biao] Qinghai Prov Geog Situat Monitoring Inst, Xining 810001, Peoples R China. RP Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China.; Li, XL (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. EM qhryblin@163.com; xilai-li@163.com; qhlxl2001@163.com; 1219493914@qq.com; 7845944@qq.com; hmjerry@163.com; wangqhnuist@sina.com; 357366709@qq.com; 1527523489@qq.com; nuistzyx@126.com; moblflyqxm@163.com TC 7 Z9 7 PD MAR PY 2021 VL 18 IS 3 BP 694 EP 705 DI 10.1007/s11629-020-6117-0 EA MAR 2021 UT WOS:000623825500001 DA 2023-03-23 ER PT J AU Liu, HY Jia, JH Lin, ZS Wang, ZY Gong, HB AF Liu, Huiyu Jia, Junhe Lin, Zhenshan Wang, Zhaoyue Gong, Haibo TI Relationship between net primary production and climate change in different vegetation zones based on EEMD detrending - A case study of Northwest China SO ECOLOGICAL INDICATORS DT Article AB The relationship between vegetation Net primary production (NPP) and climate change is critical for understanding the driving forces of vegetation changes, while less were studied based on detrending analysis and Bioclimatic variables. In this study, detrending analysis based on Ensemble Empirical Mode Decomposition (EEMD) method was adopted to assess the relationship between NPP and climate change in different vegetation zones in Northwest China. The results indicated that: (1) although monotonic increasing was the main type of vegetation NPP trend (49.42%), shifted trend accounted for 36.02% of the whole area. There were some risks of vegetation degradation in temperate desert and alpine region of the Qinghai Tibet Platea, but chances for vegetation recovery in temperate grassland and warm temperate deciduous broad-leaved forest zones; (2) EEMD-detrending analysis performed much better than linear detrending analysis for assessing the relationship between climate change and vegetation NPP; (3) compared with no detrending, EEMD-detrending reduced the importance of BIO1 (annual mean temperature) and BIO2 (mean temperature diurnal range) for vegetation NPP, but enhanced those of BIO13 (precipitation of the wettest month) and BIO15 (precipitation seasonality); (4) BIO1, BIO2, BIO12 (annual precipitation), and BIO13 mainly showed positive relationships with interannual NPP variations, except that BIO1 and BIO13 mainly showed negative relationship in temperate grassland and warm temperate deciduous broad-leaved forest zones. Interannual NPP variations were dominated by BIO12 and BIO13, except that alpine region of Tibet plateau was dominated by BIO1 and BIO2. Our results demonstrated that EEMD-detrending analysis and Bioclimatic variables can better explore the interannual vegetation-climate relationship. C1 [Liu, Huiyu; Jia, Junhe; Lin, Zhenshan; Wang, Zhaoyue; Gong, Haibo] Nanjing Normal Univ, Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Peoples R China. [Liu, Huiyu; Jia, Junhe; Lin, Zhenshan; Wang, Zhaoyue; Gong, Haibo] Nanjing Normal Univ, Minist Educ, Key Lab Virtual Geog Environm, Nanjing 210023, Peoples R China. [Liu, Huiyu; Jia, Junhe; Lin, Zhenshan; Wang, Zhaoyue; Gong, Haibo] Nanjing Normal Univ, State Key Lab Cultivat Base Geog Environm Evolut, Nanjing 210023, Peoples R China. [Liu, Huiyu; Jia, Junhe; Lin, Zhenshan; Wang, Zhaoyue; Gong, Haibo] Nanjing Normal Univ, Coll Geog Sci, Nanjing 210023, Peoples R China. [Liu, Huiyu; Jia, Junhe; Lin, Zhenshan; Wang, Zhaoyue; Gong, Haibo] Nanjing Normal Univ, Jiangsu Key Lab Environm Change & Ecol Construct, Nanjing 210023, Peoples R China. RP Liu, HY (通讯作者)，Nanjing Normal Univ, Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Peoples R China. EM liuhuiyu@njnu.edu.cn TC 21 Z9 24 PD MAR PY 2021 VL 122 AR 107276 DI 10.1016/j.ecolind.2020.107276 UT WOS:000613233900002 DA 2023-03-23 ER PT J AU Qin, PY Sun, B Li, ZY Gao, ZH Li, YF Yan, ZY Gao, T AF Qin, Pengyao Sun, Bin Li, Zengyuan Gao, Zhihai Li, Yifu Yan, Ziyu Gao, Ting TI Estimation of Grassland Carrying Capacity by Applying High Spatiotemporal Remote Sensing Techniques in Zhenglan Banner, Inner Mongolia, China SO SUSTAINABILITY DT Article AB Overgrazing directly leads to grassland degradation, which is a serious constraint to the sustainable development of animal husbandry. In drylands, grassland biomass is highly heterogeneous in space and time. It is difficult to achieve sustainable utilization of grassland resources by focusing only on the average annual carrying capacity assessment obtained from grass yield. Here, we proposed a novel approach for assessing grassland carrying capacity, taking Zhenglan Banner (County) in Inner Mongolia as the study area. First, monthly grass yield at 30 m spatial resolution was estimated, derived from Carnegie-Ames-Stanford Approach (CASA) model and spatial and temporal adaptive reflectance fusion model (STARFM). Then, based on the degree of sand mobility and degradation condition of typical steppe, the utilization patterns for sandy land and typical steppe in different grazing seasons were developed separately to obtain available grass yield. Finally, the carrying capacity at the Gacha (Village)-scale was estimated and the current livestock carrying status was evaluated to facilitate the grassland refined management. In Zhenglan Banner, the carrying capacity was 237.46 thousand cattle-units in summer. The grassland resources are being overgrazed, with an overload rate of 19.32%. At Gacha-scale, the maximum reasonable stock density was ranged from 0.06 cattle-unit/ha to 0.42 cattle-unit/ha. Fifty-one Gachas exhibited livestock overload. This study is expected to provide technical support and scientific reference data for ecological conservation and grassland management in the study area, as well as in dryland pastoral areas of northern China. C1 [Qin, Pengyao; Sun, Bin; Li, Zengyuan; Gao, Zhihai; Li, Yifu; Yan, Ziyu; Gao, Ting] Chinese Acad Forestry, Inst Forest Resource Informat Tech, Beijing 100091, Peoples R China. [Qin, Pengyao; Sun, Bin; Li, Zengyuan; Gao, Zhihai; Li, Yifu; Yan, Ziyu; Gao, Ting] Natl Forestry & Grassland Adm, Key Lab Forestry Remote Sensing & Informat Syst, Beijing 100091, Peoples R China. RP Gao, ZH (通讯作者)，Chinese Acad Forestry, Inst Forest Resource Informat Tech, Beijing 100091, Peoples R China.; Gao, ZH (通讯作者)，Natl Forestry & Grassland Adm, Key Lab Forestry Remote Sensing & Informat Syst, Beijing 100091, Peoples R China. EM qpyhebei@126.com; sunbin@ifrit.ac.cn; lizy@caf.ac.cn; zhgao@ifrit.ac.cn; li.yifu1314@163.com; yanziyu96@163.com; gaoting2167@126.com TC 2 Z9 3 PD MAR PY 2021 VL 13 IS 6 AR 3123 DI 10.3390/su13063123 UT WOS:000645805800001 DA 2023-03-23 ER PT J AU Wu, JS Li, M Zhang, XZ Fiedler, S Gao, QZ Zhou, YT Cao, WF Hassan, W Margarint, MC Tarolli, P Tietjen, B AF Wu, Jianshuang Li, Meng Zhang, Xianzhou Fiedler, Sebastian Gao, Qingzhu Zhou, Yuting Cao, Wenfang Hassan, Waseem Margarint, Mihai Ciprian Tarolli, Paolo Tietjen, Britta TI Disentangling climatic and anthropogenic contributions to nonlinear dynamics of alpine grassland productivity on the Qinghai-Tibetan Plateau SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Alpine grasslands on the Qinghai-Tibetan Plateau are sensitive and vulnerable to climate change and human activities. Climate warming and overgrazing have already caused degradation in a large fraction of alpine grasslands on this plateau. However, it remains unclear how human activities (mainly livestock grazing) regulates vegetation dynamics under climate change. Here, alpine grassland productivity (substituted with the normalized difference vegetation index, NDVI) is hypothesized to vary in a nonlinear trajectory to follow climate fluctuations and human disturbances. With generalized additive mixed modelling (GAMM) and residual-trend (RESTREND) analysis together, both magnitude and direction of climatic (in terms of temperature, precipitation, and radiation) and anthropogenic impacts on NDVI variation were examined across alpine meadows, steppes, and desert-steppes on the Qinghai-Tibetan Plateau. The results revealed that accelerating warming and greening, respectively, took place in 76.2% and 78.8% of alpine grasslands on the Qinghai-Tibetan Plateau. The relative importance of temperature, precipitation, and radiation impacts was comparable, between 20.4% and 24.8%, and combined to explain 66.2% of NDVI variance at the pixel scale. The human influence was strengthening and weakening, respectively, in 15.5% and 14.3% of grassland pixels, being slightly larger than any sole climatic variable across the entire plateau. Anthropogenic and climatic factors can be in opposite ways to affect alpine grasslands, even within the same grassland type, likely regulated by plant community assembly and species functional traits. Therefore, the underlying mechanisms of how plant functional diversity regulates nonlinear ecosystem response to climatic and anthropogenic stresses should be carefully explored in the future. C1 [Wu, Jianshuang; Gao, Qingzhu; Cao, Wenfang; Hassan, Waseem] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Wu, Jianshuang; Fiedler, Sebastian; Tietjen, Britta] Free Univ Berlin, Inst Biol, Theoret Ecol, D-14195 Berlin, Germany. [Li, Meng; Zhang, Xianzhou] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, Beijing 100101, Peoples R China. [Li, Meng] Nantong Univ, Sch Geog Sci, Nantong 226007, Jiangsu, Peoples R China. [Fiedler, Sebastian] Univ Bayreuth, Dept Ecol Modelling, D-95448 Bayreuth, Germany. [Zhou, Yuting] Oklahoma State Univ, Dept Geog, Stillwater, OK 74078 USA. [Cao, Wenfang; Tarolli, Paolo] Univ Padua, Dept Land Environm Agr & Forestry, I-35020 Legnaro, PD, Italy. [Margarint, Mihai Ciprian] Alexandru Ioan Cuza Univ, Geog & Geol Fac, Dept Geog, Iasi 700505, Romania. [Fiedler, Sebastian; Tietjen, Britta] Berlin Brandenburg Inst Adv Biodivers Res, D-14195 Berlin, Germany. RP Wu, JS (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM wujianshuang@caas.cn TC 27 Z9 28 PD MAR 1 PY 2021 VL 281 AR 111875 DI 10.1016/j.jenvman.2020.111875 UT WOS:000618047500003 DA 2023-03-23 ER PT J AU Zhao, YT Pu, YF Lin, HL Tang, R AF Zhao, Yuting Pu, Yanfei Lin, Huilong Tang, Rong TI Examining Soil Erosion Responses to Grassland Conversation Policy in Three-River Headwaters, China SO SUSTAINABILITY DT Article AB Soil erosion in the Three-River Headwaters (TRH) region has continued to intensify in recent decades due to human activities and climate change. To reverse this situation, the Chinese central government has launched the Subsidy and Incentive System for Grassland Conservation (SISGC). As a sign of the effectiveness of SISGC implementation, the dynamic changes of soil erosion can provide timely feedback for decision makers and managers. The Revised Universal Soil Loss Equation (RUSLE) model was used to simulate the spatial distribution of soil erosion before and after SISGC implementation, and Mann-Kendall (MK) test to reveal the effect of policy implementation. The results showed that: (1) the soil erosion in the TRH was mainly mild (83.83% of the total eroded area), and the average soil erosion rate and the total erosion were 13.63 t ha(-1) y(-1) and 323.58 x 10(6) t y(-1) respectively before SISGC implementation; (2) SISGC implementation has curbed soil erosion. After SISGC implementation, the total soil erosion decreased by 3.80%, which showed obvious differences between grassland types; (3) The influences of SISGC were mainly because it has increased vegetation cover, further decreasing soil erosion. However, soil erosion in Alpine grassland has deteriorated, indicating direct targeted policymaking should be on the agenda. Furthermore, SISGC should be continued and grassland-type-oriented to restore the grassland ecosystem. C1 [Zhao, Yuting; Pu, Yanfei; Lin, Huilong; Tang, Rong] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Zhao, Yuting; Pu, Yanfei; Lin, Huilong; Tang, Rong] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730000, Peoples R China. [Zhao, Yuting; Pu, Yanfei; Lin, Huilong; Tang, Rong] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Minist Agr & Rural Affairs, Lanzhou 730000, Peoples R China. RP Lin, HL (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China.; Lin, HL (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730000, Peoples R China.; Lin, HL (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Minist Agr & Rural Affairs, Lanzhou 730000, Peoples R China. EM zhaoyt14@lzu.edu.cn; puyf19@lzu.edu.cn; linhuilong@lzu.edu.cn; tangr19@lzu.edu.cn TC 1 Z9 1 PD MAR PY 2021 VL 13 IS 5 AR 2702 DI 10.3390/su13052702 UT WOS:000628571900001 DA 2023-03-23 ER PT J AU Li, JX Li, XL Gao, J Kazhaocairang Ma, GL Qi, XZ AF Li, Jiexia Li, Xilai Gao, Jay Kazhaocairang Ma, Geliang Qi, Xuezhong TI Micro-scale fragmentation of the alpine meadow landscape on the Qinghai-Tibet Plateau under external disturbances SO CATENA DT Article AB Detailed characterization of alpine meadow ecosystems using spatial metrics is important to understand the underlying processes of meadow degradation and to inform its proper management. The change in the fragmentation of the alpine meadow on the Qinghai-Tibet Plateau during 2018-2019 was studied in relation to plateau pika (Ochotona curzoniae) population and simulated grazing both independently and interactively. For the first time this study has quantified their effect on the changes in the spatial metrics of bare and healthy meadow patches with the assistance of multi-temporal UAV images in ArcGIS. The spatial index reflecting the fragmentation degree of landscape caused by external disturbances was obtained via spatial analysis in the Fragstats 4.2 software. The results showed that the impact of pika on landscape fragmentation was higher than that of simulated grazing, so pikas populaton should be controlled within the manageable level. The influence of each disturbance on the degree of fragmentation was the highest in high density pika and severe mowing plot, followed by the plots of medium density pika, the control treatments, high density pika, other three interactive effect groups, moderate mowing and severe mowing. In the interactive effect, at the same mowing intensity, landscape fragmentation increased with pika population. At the same pika population, landscape fragmentation increased with mowing intensity. The correlation coefficient between the change in pika burrows and area of bare patches is 0.538, and the proportion of bare patches to the landscape is 0.541. This study provides a reference for studying the feasibility of grassland fragmentation monitoring in the future and the landscape stability of the alpine meadow. C1 [Li, Jiexia; Li, Xilai] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Li, Jiexia; Li, Xilai] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Qinghai, Peoples R China. [Li, Jiexia; Gao, Jay] Univ Auckland, Sch Environm, Private Bag 92019, Auckland, New Zealand. [Kazhaocairang; Ma, Geliang; Qi, Xuezhong] Grassland Integrated Profess Team Mongolian Auton, Huangnan Tibetan Autonom 811500, Henan, Peoples R China. RP Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China.; Gao, J (通讯作者)，Univ Auckland, Private Bag 92019, Auckland, New Zealand. EM jiexia_li@163.com; xilai-li@163.com; jg.gao@auckland.ac.nz TC 13 Z9 14 PD JUN PY 2021 VL 201 AR 105220 DI 10.1016/j.catena.2021.105220 EA FEB 2021 UT WOS:000631043700033 DA 2023-03-23 ER PT J AU Li, CY Peng, F Xue, X Lai, CM Zhang, WJ You, QG Chen, XJ Zhang, XQ Wang, T AF Li, Cheng-yang Peng, Fei Xue, Xian Lai, Chi-min Zhang, Wen-juan You, Quan-gang Chen, Xiao-jie Zhang, Xue-qin Wang, Tao TI Degradation stage effects on vegetation and soil properties interactions in alpine steppe SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB In recent decades, overgrazing and the warming and drying climate have resulted in significant degradation of alpine grasslands in the source region of the Yellow River. However, research into the relationships between vegetation and soil properties has mainly focused on an overall degradation stage, and few studies have investigated which soil properties can impact vegetation change at different stages of degradation. Vegetation and soil properties were observed in the field and measured in the laboratory for different predefined stages of degradation for alpine grassland in Maduo County in the source region of the Yellow River. Results show that: 1) the aboveground and belowground biomass, soil organic carbon, total nitrogen, nitrate, and ammonia content did not decrease significantly from the intact to moderate degradation stage, but decreased significantly at severe and very severe stages of degradation; 2) dominant plant species shifted from gramineaes and sedges to forbs; 3) the species richness and Pielou evenness indices decreased significantly at the very severe degradation stage, the Shannon-Wiener diversity index increased at the slight and moderate degradation, but decreased at the severe and very severe degradation stages; 4) soil bulk density was the strongest soil driver for changes in the plant biomass and community diversity at the intact, slight and moderate degradation stages, whereas soil organic carbon and nitrate nitrogen content were the main driving factors for changes in plant biomass and diversity at the severe and very severe degradation stages. Our results suggest that there may be different interactions between soil properties and plants before and after moderate stages of degradation. C1 [Li, Cheng-yang; Peng, Fei; Xue, Xian; Lai, Chi-min; Zhang, Wen-juan; You, Quan-gang; Chen, Xiao-jie; Zhang, Xue-qin; Wang, Tao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. [Li, Cheng-yang; Lai, Chi-min; Zhang, Wen-juan; Chen, Xiao-jie; Zhang, Xue-qin] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Peng, Fei] Int Platform Dryland Res & Educ, Tottori 6800001, Japan. [Peng, Fei] Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. RP Peng, F (通讯作者)，Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. EM lichengyang@lzb.ac.cn; pengfei@lzb.ac.cn; xianxue@lzb.ac.cn; laichimin@lzb.ac.cn; zhangwenjuan@lzb.ac.cn; youqg@lzb.ac.cn; philerochen@gmail.com; zhangxueqin17@mails.ucas.ac.cn; wangtao@lzb.ac.cn TC 5 Z9 5 PD MAR PY 2021 VL 18 IS 3 BP 646 EP 657 DI 10.1007/s11629-020-6192-2 EA FEB 2021 UT WOS:000618150000002 DA 2023-03-23 ER PT J AU Tian, J Zong, N Hartley, IP He, NP Zhang, JJ Powlson, D Zhou, JZ Kuzyakov, Y Zhang, FS Yu, GR Dungait, JAJ AF Tian, Jing Zong, Ning Hartley, Iain P. He, Nianpeng Zhang, Jinjing Powlson, David Zhou, Jizhong Kuzyakov, Yakov Zhang, Fusuo Yu, Guirui Dungait, Jennifer A. J. TI Microbial metabolic response to winter warming stabilizes soil carbon SO GLOBAL CHANGE BIOLOGY DT Article AB Current consensus on global climate change predicts warming trends with more pronounced temperature changes in winter than summer in the Northern Hemisphere at high latitudes. Moderate increases in soil temperature are generally related to faster rates of soil organic carbon (SOC) decomposition in Northern ecosystems, but there is evidence that SOC stocks have remained remarkably stable or even increased on the Tibetan Plateau under these conditions. This intriguing observation points to altered soil microbial mediation of carbon-cycling feedbacks in this region that might be related to seasonal warming. This study investigated the unexplained SOC stabilization observed on the Tibetan Plateau by quantifying microbial responses to experimental seasonal warming in a typical alpine meadow. Ecosystem respiration was reduced by 17%-38% under winter warming compared with year-round warming or no warming and coincided with decreased abundances of fungi and functional genes that control labile and stable organic carbon decomposition. Compared with year-round warming, winter warming slowed macroaggregate turnover rates by 1.6 times, increased fine intra-aggregate particulate organic matter content by 75%, and increased carbon stabilized in microaggregates within stable macroaggregates by 56%. Larger bacterial "necromass" (amino sugars) concentrations in soil under winter warming coincided with a 12% increase in carboxyl-C. These results indicate the enhanced physical preservation of SOC under winter warming and emphasize the role of soil microorganisms in aggregate life cycles. In summary, the divergent responses of SOC persistence in soils exposed to winter warming compared to year-round warming are explained by the slowing of microbial decomposition but increasing physical protection of microbially derived organic compounds. Consequently, the soil microbial response to winter warming on the Tibetan Plateau may cause negative feedbacks to global climate change and should be considered in Earth system models. C1 [Tian, Jing; Zhang, Fusuo] China Agr Univ, Natl Acad Agr Green Dev, Coll Resources & Environm Sci, Key Lab Plant Soil Interact,Minist Educ, Beijing, Peoples R China. [Tian, Jing; Zong, Ning; He, Nianpeng; Yu, Guirui] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China. [Hartley, Iain P.] Univ Exeter, Coll Life & Environm Sci, Geog, Exeter, Devon, England. [Zhang, Jinjing] Jilin Agr Univ, Coll Resource & Environm Sci, Key Lab Soil Resource Sustainable Utilizat Commod, Changchun, Peoples R China. [Powlson, David; Dungait, Jennifer A. J.] Rothamsted Res, Dept Sustainable Agr Sci, Harpenden, Herts, England. [Zhou, Jizhong] Univ Oklahoma, Dept Microbiol & Plant Biol, Inst Environm Genom, Norman, OK USA. [Zhou, Jizhong] Univ Oklahoma, Sch Civil Engn & Environm Sci, Norman, OK USA. [Zhou, Jizhong] Lawrence Berkeley Natl Lab, Earth & Environm Sci, Berkeley, CA USA. [Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, Gottingen, Germany. [Kuzyakov, Yakov] RUDN Univ, Agrotechnol Inst, Moscow, Russia. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan, Russia. [Dungait, Jennifer A. J.] SRUC Scotlands Rural Coll, Carbon Management Ctr, Edinburgh, Midlothian, Scotland. RP Tian, J (通讯作者)，China Agr Univ, Natl Acad Agr Green Dev, Coll Resources & Environm Sci, Key Lab Plant Soil Interact,Minist Educ, Beijing, Peoples R China.; Tian, J; Yu, GR (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China. EM tianj@igsnrr.ac.cn; yugr@igsnrr.ac.cn TC 23 Z9 23 PD MAY PY 2021 VL 27 IS 10 BP 2011 EP 2028 DI 10.1111/gcb.15538 EA FEB 2021 UT WOS:000617648500001 DA 2023-03-23 ER PT J AU Ren, YH Zhu, YP Baldan, D Fu, MD Wang, B Li, JS Chen, AP AF Ren, Yueheng Zhu, Yanpeng Baldan, Davide Fu, Mengdi Wang, Bin Li, Junsheng Chen, Anping TI Optimizing livestock carrying capacity for wild ungulate-livestock coexistence in a Qinghai-Tibet Plateau grassland SO SCIENTIFIC REPORTS DT Article AB Wild ungulates are an important part of terrestrial ecosystems and play a critical role in maintaining ecosystem health and integrity. In many grassland ecosystems that are habituated by wild ungulates, the coexistence of domestic ungulates has created a conflict over grazing resources. Solving this conflict requires a balanced and sustainable policy that satisfies both the needs of wildlife protection and food production. Here, we assess the optimal grassland livestock carrying capacity of an alpine grassland on the Qinghai-Tibet Plateau, given the coexistence of wild populations of kiangs (Equus kiang) and Tibetan gazelles (Procapra picticaudata), two key species grazing in this region. We use kriging and the MaxEnt method to estimate the population sizes of kiangs and Tibetan gazelles in Maduo County, Qinghai Province. We then convert the estimated population size of the two species into sheep units and calculate the residual carrying capacity for livestock grazing. We show that after accounting for the grazing need for kiangs and Tibetan gazelles, grassland in Maduo is capable of supporting 420,641 sheep units, which is slightly more than the current livestock population. However, the residual carrying capacity is highly uneven across the region, and overgrazing is found in many areas of Maduo, especially in northern Maduo. This research provides a useful framework for planning sustainable livestock farming for the Qinghai-Tibet Plateau and other regions facing wildlife-livestock conflict. C1 [Ren, Yueheng; Zhu, Yanpeng; Fu, Mengdi; Li, Junsheng] Chinese Res Inst Environm Sci, State Environm Protect Key Lab Reg Ecoproc & Func, Beijing 100012, Peoples R China. [Baldan, Davide] Univ Nevada, Dept Biol, Reno, NV 89557 USA. [Wang, Bin] Hunan Normal Univ, Coll Life Sci, Changsha 410006, Peoples R China. [Chen, Anping] Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. [Chen, Anping] Colorado State Univ, Grad Degree Program Ecol, Ft Collins, CO 80523 USA. RP Zhu, YP; Li, JS (通讯作者)，Chinese Res Inst Environm Sci, State Environm Protect Key Lab Reg Ecoproc & Func, Beijing 100012, Peoples R China.; Chen, AP (通讯作者)，Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA.; Chen, AP (通讯作者)，Colorado State Univ, Grad Degree Program Ecol, Ft Collins, CO 80523 USA. EM zhuyp@craes.org.cn; lijsh@craes.org.cn; anping.chen@colostate.edu TC 2 Z9 3 PD FEB 11 PY 2021 VL 11 IS 1 AR 3635 DI 10.1038/s41598-021-83207-y UT WOS:000626726100008 DA 2023-03-23 ER PT J AU He, LXZ Jia, ZQ Li, QX Zhang, YY Wu, RN Dai, J Gao, Y AF He, Lingxianzi Jia, Zhiqing Li, Qingxue Zhang, Youyan Wu, Rina Dai, Jie Gao, Ya TI Fine root dynamic characteristics and effect on plantation's carbon sequestration of three Salix shrub plantations in Tibetan Plateau alpine sandy land SO ECOLOGY AND EVOLUTION DT Article AB Desertification land in Gonghe Basin of Tibetan Plateau, China accounts for 91.9% of the total land area. Vegetation restoration and reconstruction with desert shrubs in degraded ecosystem are effective ways to prevent and control desertification. However, the evaluation studies of fine root dynamic characteristics of desert shrubs and their contribution to carbon sequestration of plantation are limited. To gain a better understanding of vegetation restoration, the vertical distribution of fine root biomass, fine root decomposition, fine root turnover was investigated, as well as their coupling effect on carbon sequestration of plantation in three desert vegetation. The results estimated that the total decomposition time of fine roots of Salix cheilophila (S. cheilophila), Salix psammophila (S. psammophila), and Salix microstachya (S. microstachya) are 39.00, 27.99 and 35.95 years. Biomass carbon density for three Salix plantations ranged from 1.42 to 2.39 t/hm(2), which showed that three Salix plantations in alpine sandy land are an important carbon pool. In addition, fine root biomass carbon density for the three shrub plantations varied significantly. Fine root biomass carbon density for S. psammophila reached the largest among the three plantations, which was 1.48 t/hm(2), accounting for the ratio of 62% of the plantation total biomass carbon density. The results indicated that the root system of S. psammophila, especially the fine roots, was very developed, which was conducive to soil water transportation and carbon sequestration. Therefore, S. psammophila might be a better species for carbon sequestration of plantation in alpine sandy areas. The carbon input from the fine roots of the three shrub plantations through decomposition and turnover into the plantations accounts for 11.5% to 15.5% of total carbon sequestration of plantations. Therefore, the fine roots dynamics must be considered for long-term carbon pool estimations in three Salix plantations, otherwise the total carbon sequestration of plantations would be underestimated. C1 [He, Lingxianzi; Jia, Zhiqing; Li, Qingxue; Zhang, Youyan; Wu, Rina; Dai, Jie] Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. [He, Lingxianzi; Jia, Zhiqing; Li, Qingxue] Qinghai Gonghe Desert Ecosyst Res Stn, Shazhuyu Town, Qinghai, Peoples R China. [Jia, Zhiqing; Gao, Ya] Chinese Acad Forestry, Res Inst Forestry, Beijing, Peoples R China. RP Jia, ZQ (通讯作者)，Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. EM jiazhiqing369@126.com TC 3 Z9 3 PD MAR PY 2021 VL 11 IS 6 BP 2645 EP 2659 DI 10.1002/ece3.7221 EA FEB 2021 UT WOS:000613841500001 DA 2023-03-23 ER PT J AU Chen, XP Zhang, T Guo, RY Li, HY Zhang, R Degen, AA Huang, KW Wang, XM Bai, YF Shang, ZH AF Chen, Xiaopeng Zhang, Tao Guo, Ruiying Li, Haiyan Zhang, Rui Degen, A. Allan Huang, Kewei Wang, Ximing Bai, Yanfu Shang, Zhanhuan TI Fencing enclosure alters nitrogen distribution patterns and tradeoff strategies in an alpine meadow on the Qinghai-Tibetan Plateau SO CATENA DT Article AB The grasslands of Qinghai-Tibetan Plateau have become extremely degraded, resulting in widespread deficiency of soil N. In efforts to restore degraded lands, fencing enclosure has been used extensively. However, the effect of fencing on N allocation patterns and nutritional strategy of alpine plants are equivocal. In this study, we used N-15 tracer (CO ((NH2)-N-15)(2), 10 g N m(-2)) to examine the allocation and distribution of N in plants and soil in grasslands either grazed heavily by livestock or fenced for three years in an alpine meadow of Northern Tibet. The N-15 recovery (N-15(rec)) in shoots of the fenced enclosure increased by 207% in grasses, decreased by 103% in forbs, and did not change in sedges when compared to the grazed meadow. The N-15(rec) in shoots accounted for only 1.97% and 4.65% of the total N in the grazed and fenced meadows, respectively. Fencing increased soil N-15 content at 0-5 cm depth by 6.9%, but decreased the content at 5-10 cm depth by 11.7%. The results demonstrated that fencing altered the soil N distribution by increasing N-15 rec in top soil and by decreasing N-15(rec) in subsurface soil. In addition, fencing had no impact on root N-15 storage (33%-39%), N-15 losses (9.6%-12.5%) and soil available N-15(rec) (NH4+ -N, NO3--N and light fraction organic N), but decreased root:shoot N-15(rec) ratio by 49.8% (16.9:1 in grazed and 8.4:1 in fenced grassland). Fencing increased soil organic carbon, total N and NO3--N concentrations, which indicated that the strategy of the plants was to allocate relatively more N to roots in nutrient-poor soil (grazed) but relatively more N to shoots in nutrient-rich soil (fenced). C1 [Chen, Xiaopeng] Shanxi Agr Univ, Coll Grassland Sci, Taigu 030801, Peoples R China. [Chen, Xiaopeng; Zhang, Tao; Guo, Ruiying; Wang, Ximing; Bai, Yanfu; Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Chen, Xiaopeng; Li, Haiyan] Northeast Normal Univ, Inst Grassland Sci, Key Lab Vegetat Ecol, Minist Educ, Changchun 130024, Jilin, Peoples R China. [Zhang, Rui] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. [Degen, A. Allan] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, IL-8410500 Beer Sheva, Israel. [Huang, Kewei] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Shang, Zhanhuan] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Area, Xining 810008, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. EM shangzhh@lzu.edu.cn TC 10 Z9 12 PD FEB PY 2021 VL 197 AR 104948 DI 10.1016/j.catena.2020.104948 UT WOS:000597208600007 DA 2023-03-23 ER PT J AU Duan, HC Xue, X Wang, T Kang, WP Liao, J Liu, SL AF Duan, Hanchen Xue, Xia Wang, Tao Kang, Wenping Liao, Jie Liu, Shulin TI Spatial and Temporal Differences in Alpine Meadow, Alpine Steppe and All Vegetation of the Qinghai-Tibetan Plateau and Their Responses to Climate Change SO REMOTE SENSING DT Article AB Alpine meadow and alpine steppe are the two most widely distributed nonzonal vegetation types in the Qinghai-Tibet Plateau. In the context of global climate change, the differences in spatial-temporal variation trends and their responses to climate change are discussed. It is of great significance to reveal the response of the Qinghai-Tibet Plateau to global climate change and the construction of ecological security barriers. This study takes alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau as the research objects. The normalized difference vegetation index (NDVI) data and meteorological data were used as the data sources between 2000 and 2018. By using the mean value method, threshold method, trend analysis method and correlation analysis method, the spatial and temporal variation trends in the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau were compared and analyzed, and their differences in the responses to climate change were discussed. The results showed the following: (1) The growing season length of alpine meadow was 145 similar to 289 d, while that of alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau was 161 similar to 273 d, and their growing season lengths were significantly shorter than that of alpine meadow. (2) The annual variation trends of the growing season NDVI for the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau increased obviously, but their fluctuation range and change rate were significantly different. (3) The overall vegetation improvement in the Qinghai-Tibet Plateau was primarily dominated by alpine steppe and alpine meadow, while the degradation was primarily dominated by alpine meadow. (4) The responses between the growing season NDVI and climatic factors in the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau had great spatial heterogeneity in the Qinghai-Tibet Plateau. These findings provide evidence towards understanding the characteristics of the different vegetation types in the Qinghai-Tibet Plateau and their spatial differences in response to climate change. C1 [Duan, Hanchen; Xue, Xia; Wang, Tao; Kang, Wenping; Liao, Jie; Liu, Shulin] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. RP Xue, X (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. EM hcduan@lzb.ac.cn; xianxue@lzb.ac.cn; wt@lzb.ac.cn; kangwp@lzb.ac.cn; liaojie@lzb.ac.cn; liusl@lzb.ac.cn TC 29 Z9 32 PD FEB PY 2021 VL 13 IS 4 AR 669 DI 10.3390/rs13040669 UT WOS:000624426900001 DA 2023-03-23 ER PT J AU Liu, CL Li, WL Xu, J Wei, W Xue, PF Yan, HP AF Liu, Chenli Li, Wenlong Xu, Jing Wei, Wei Xue, Pengfei Yan, Hepiao TI Response of soil nutrients and stoichiometry to grazing management in alpine grassland on the Qinghai-Tibet Plateau SO SOIL & TILLAGE RESEARCH DT Article AB Soil nutrients and stoichiometry are two important fertility indicators for grassland ecosystems, and are essential to maintain ecosystem function and protect land from degradation. Although many case studies have been conducted, the effect of grazing management on soil nutrients of alpine grassland is still poorly understood because of the complex nature of grassland soil. In this study, we synthesized the results of 53 peer-reviewed publications and conducted a meta-analysis to explore the effects of grazing on soil nutrient levels. Our results indicated that grazing significantly decreased soil organic carbon (SOC,-13.7 %), soil total nitrogen (TN,-12.7 %), soil total phosphorus (TP,-11.6 %), soil available phosphorus (-7.7 %), soil moisture (SM,-21.1 %) and soil C:N ratio (-3.4 %). In contrast, grazing significantly increased soil bulk density (+16.7 %) and soil temperature (+8.5 %), while it had no effect on soil available nitrogen, or the ratios of C:P and N:P in soil. Specifically, grazing effects on SOC, TN and TP decrease with increasing grazing intensity, but light grazing had no significant effect on them. The response ratio of SOC was significantly positively correlated with the response ratio of TN, SM, C:N and C:P ratios (p < 0.01), suggesting that the mutual influence of soil nutrient variables in alpine grassland under grazing. In addition, the response of soil nutrients to grazing was also affected by grazing season, livestock type and grazing duration. Our study provides new insights into how soil nutrient levels are impacted by different grazing management strategies in alpine grassland ecosystems on the QTP. This information can be form the basis for future studies into sustainable management of alpine grassland. C1 [Liu, Chenli; Li, Wenlong; Wei, Wei; Xue, Pengfei; Yan, Hepiao] Lanzhou Univ, Coll Pastoral Agr Sci & Technol,Minist Educ, Minist Agr & Rural Affairs,Key Lab Grassland Live, Engn Res Ctr Grassland Ind,State Key Lab Grasslan, Lanzhou 730000, Peoples R China. [Xu, Jing] Lanzhou Univ Finance & Econ, Sch Agr & Forestry Econ & Management, Lanzhou 730020, Peoples R China. RP Li, WL (通讯作者)，222 South Tianshui Rd, Lanzhou 730000, Gansu, Peoples R China. EM liuchl18@lzu.edu.cn; wllee@lzu.edu.cn TC 20 Z9 23 PD FEB PY 2021 VL 206 AR 104822 DI 10.1016/j.still.2020.104822 UT WOS:000596192800003 DA 2023-03-23 ER PT J AU Wang, J Wang, XT Liu, GB Zhang, C Wang, GL AF Wang, Jie Wang, Xiangtao Liu, Guobin Zhang, Chao Wang, Guoliang TI Bacterial richness is negatively related to potential soil multifunctionality in a degraded alpine meadow SO ECOLOGICAL INDICATORS DT Article AB Fungal richness and community composition are known to be positively associated with soil multifunctionality. However, the contributions of bacterial and fungal communities to the multiple soil functions of alpine meadow ecosystems have not been widely examined. Here, we surveyed the soil in Qinghai-Tibetan alpine meadows and classified the extent of degradation as undegraded, lightly degraded, moderately degraded, and severely degraded to clarify the associations between microbial diversity (including bacteria and fungi) and potential soil multifunctionality. Bacterial and fungal compositions were detected by sequencing of the 16S rDNA and internal transcribed spacer amplicons, respectively. Functions associated with nutrient cycling (dissolved organic nitrogen and carbon, available phosphorus, NO3-, NH4+, C, N, P-cycle enzymes) and climate regulation (CO2 and N2O emissions) were also examined. Bacterial, rather than fungal, richness was negatively associated with potential soil multifunctionality, which decreased along the degradation gradient. Structural equation modeling explained 79.6% of the variation in potential soil multifunctionality and confirmed that, in addition to bacterial community richness and composition, organic carbon and moisture were important drivers of potential soil multifunctionality. These results suggest that higher bacterial richness is associated with lower potential soil multifunctionality in alpine meadow ecosystems. Among the bacterial taxa, only similar to 12% of bacterial genera were identified as predictors of multifunctionality, suggesting functional redundancy of the bacterial community in the meadow ecosystem. Rhodanobacter, Mucilaginibacter, Rhodococcus, and Bosea, belonging to the Proteobacteria and the Actinobacteria phyla were identified as critical for maintaining potential soil multifunctionality. Our results suggest that bacterial richness is negatively related to potential soil multifunctionality in alpine meadow ecosystems and there is no correlation between potential multifunctionality and fungal richness. C1 [Wang, Jie; Liu, Guobin; Zhang, Chao; Wang, Guoliang] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Wang, Xiangtao] Xizang Agr & Anim Husb Coll, Dept Anim Sci, Linzhi 860000, Peoples R China. [Liu, Guobin] Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. RP Zhang, C; Wang, GL (通讯作者)，Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. EM zhangchao1985@nwafu.edu.cn; glwang@nwsuaf.edu.cn TC 16 Z9 16 PD FEB PY 2021 VL 121 AR 106996 DI 10.1016/j.ecolind.2020.106996 UT WOS:000604888900009 DA 2023-03-23 ER PT J AU Xu, YD Dong, SK Shen, H Xiao, JN Li, S Gao, XX Wu, SN AF Xu, Yu-dan Dong, Shi-kui Shen, Hao Xiao, Jian-nan Li, Shuai Gao, Xiao-xia Wu, Sheng-nan TI Degradation significantly decreased the ecosystem multifunctionality of three alpine grasslands: evidences from a large-scale survey on the Qinghai-Tibetan Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Owing to the joint effects of ecosystem fragility, anthropogenic disturbance and climate change, alpine grasslands (alpine meadow, alpine steppe and alpine desert) have experienced serious degradation during the past several decades. Grasslands degradation has severely affected the delivery of ecosystem multifunctionality (EMF) and services, and then threatens the livelihood of local herdsmen and ecological security of China. However, we still lack comprehensive insights about the effects of degradation and climatic factors on EMF of alpine grasslands, especially for alpine desert ecosystem. Therefore, we applied a large-scale field investigation to answer this question. Our results suggested grassland degradation significantly decreased the belowground ecosystem multifunctionality (BEMF) and EMF of alpine grasslands and aboveground ecosystem multifunctionality (AEMF) of alpine meadow, while did not reduce the AEMF of alpine steppe and desert. Except for the insignificant difference between degraded steppe and degraded desert in AEMF, the alpine meadow showed the highest AEMF, BEMF and EMF, alpine steppe ranked the second and alpine desert was the lowest. AEMF, BEMF and EMF of health alpine grasslands were strongly affected by mean annual precipitation (MAP) (19%-51%) and mean annual temperature (MAT) (9%-36%), while those of degraded meadow and degraded desert were not impacted by precipitation and temperature. AEMF and BEMF showed a synergistic relationship in healthy alpine grasslands (12%-28%), but not in degraded grasslands. Our findings emphasized the urgency of implementing the feasible ecological restoration project to mitigate the negative influences of grassland degradation on EMF of alpine ecosystems. C1 [Xu, Yu-dan; Dong, Shi-kui; Shen, Hao; Xiao, Jian-nan; Gao, Xiao-xia] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Dong, Shi-kui; Wu, Sheng-nan] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. [Li, Shuai] Shanxi Agr Univ, Coll Resources & Environm, Jinzhong 030801, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China.; Dong, SK (通讯作者)，Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. EM xyd124680@163.com; dongshikui@sina.com; sh22@vip.qq.com; 1275434280@qq.com; 413160609@qq.com; gaoxiaoxia0113@163.com; 1079993460@qq.com TC 8 Z9 9 PD FEB PY 2021 VL 18 IS 2 BP 357 EP 366 DI 10.1007/s11629-020-6472-x UT WOS:000615794600005 DA 2023-03-23 ER PT J AU Wang, JS Quan, Q Chen, WN Tian, DS Ciais, P Crowther, TW Mack, MC Poulter, B Tian, HQ Luo, YQ Wen, XF Yu, GR Niu, SL AF Wang, Jinsong Quan, Quan Chen, Weinan Tian, Dashuan Ciais, Philippe Crowther, Thomas W. Mack, Michelle C. Poulter, Benjamin Tian, Hanqin Luo, Yiqi Wen, Xuefa Yu, Guirui Niu, Shuli TI Increased CO2 emissions surpass reductions of non-CO2 emissions more under higher experimental warming in an alpine meadow SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB It is well documented that warming can accelerate greenhouse gas (GHG) emissions, further inducing a positive feedback and reinforcing future climate warming. However, how different kinds of GHGs respond to various warming magnitudes remains largely unclear, especially in the cold regions that are more sensitive to climate warming. Here, we concurrently measured carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes and their total balance in an alpine meadow in response to three levels of warming (ambient, +1.5 degrees C, +3.0 degrees C). We found warming-induced increases in CH4 uptake, decreases in N2O emissions and increases in CO2 emissions at the annual basis. Expressed as CO2-equivalents with a global warming potential of 100 years (GWP100), the enhancement of CH4 uptake and reduction of N2O emissions offset only 9% of the warming-induced increase in CO2 emissions for 15 degrees C warming, and only 7% for 3.0 degrees C warming. CO2 emissions were strongly stimulated, leading to a significantly positive feedback to climate system, for 3.0 degrees C warming but less for 1.5 degrees C warming. The warming with 3.0 degrees C altered the total GHG balance mainly by stimulating CO2 emissions in the non-growing season due to warmer soil temperatures, longer unfrozen period, and increased soil water content. The findings provide an empirical evidence that warming beyond global 2 degrees C target can trigger a positive GHG-climate feedback and highlight the contribution from non-growing season to this positive feedback loop in cold ecosystems. (C) 2021 Elsevier B.V. All rights reserved. C1 [Wang, Jinsong; Quan, Quan; Chen, Weinan; Tian, Dashuan; Wen, Xuefa; Yu, Guirui; Niu, Shuli] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Wang, Jinsong; Mack, Michelle C.; Luo, Yiqi] No Arizona Univ, Ctr Ecosyst Sci & Soc, Flagstaff, AZ 86011 USA. [Wang, Jinsong; Mack, Michelle C.; Luo, Yiqi] No Arizona Univ, Dept Biol Sci, Flagstaff, AZ 86011 USA. [Quan, Quan; Chen, Weinan; Wen, Xuefa; Yu, Guirui; Niu, Shuli] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Ciais, Philippe] UVSQ, Lab Sci Climat & Environm LSCE, CEA, CNRS, F-91191 Gif Sur Yvette, France. [Crowther, Thomas W.] Swiss Fed Inst Technol, Dept Environm Syst Sci, Inst Integrat Biol, CH-8092 Zurich, Switzerland. [Poulter, Benjamin] NASA, Goddard Space Flight Ctr, Code 916, Greenbelt, MD 20771 USA. [Tian, Hanqin] Auburn Univ, Int Ctr Climate & Global Change Res, Sch Forestry & Wildlife Sci, Auburn, AL 36849 USA. RP Niu, SL (通讯作者)，Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China.; Niu, SL (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM sniu@igsnrr.ac.cn TC 9 Z9 9 PD MAY 15 PY 2021 VL 769 AR 144559 DI 10.1016/j.scitotenv.2020.144559 EA JAN 2021 UT WOS:000626618100043 DA 2023-03-23 ER PT J AU Wei, X Wu, PF AF Wei, Xue Wu, Pengfei TI Responses of soil insect communities to alpine wetland degradation on the eastern Qinghai-Tibetan Plateau, China SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB The wetlands on Earth are under different levels of degradation, and over half of them have even been lost during the 20th century. However, the response of soil insect communities to alpine wetland degradation is unknown, particularly in the Zoige? wetland, which spanning northern Sichuan, southern Gansu and Qinghai Provinces of China. Four habitats, including wet meadows, grassland meadows, moderately degraded meadows and severely degraded meadows, were selected in the Zoige? wetland, and the soil insect communities, plant communities and soil properties were investigated from April 2009 to October 2011. Diptera larvae and Coleoptera were the most abundant taxa. The soil insect taxonomic composition in the severely degraded meadows was clearly different from these of the others. The soil insect abundance significantly increased in the grassland meadows and declined in the severely degraded meadows. Similar response was found for the abundance of the Diptera larvae. The taxonomic richness and diversity of the soil insect community declined significantly in the severely degraded meadows, as well as the abundances of Coleoptera larvae and adults. The plant community and soil physico-chemical properties together determined the spatial distributions of the soil insect communities, and the avail-able soil P and K and vegetation height were the main factors that determined the abundances and diversities of the soil insect communities. Our observations demonstrated that the soil insect communities were sensitive to alpine wetland degradation, which suggests that there are drastic changes in ecological function during wetland degradation. C1 [Wei, Xue; Wu, Pengfei] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. RP Wu, PF (通讯作者)，Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. EM wupf@swun.edu.cn TC 5 Z9 8 PD MAR-APR PY 2021 VL 103 AR 103276 DI 10.1016/j.ejsobi.2020.103276 EA JAN 2021 UT WOS:000633040800006 DA 2023-03-23 ER PT J AU Du, ZY Wang, XD Xiang, J Wu, Y Zhang, B Yan, Y Zhang, XK Cai, YJ AF Du, Ziyin Wang, Xiaodan Xiang, Jian Wu, Yong Zhang, Bin Yan, Yan Zhang, Xiaoke Cai, Yanjiang TI Yak dung pat fragmentation affects its carbon and nitrogen leaching in Northern Tibet, China SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB The dung excreted by yaks (Bos grunniens) into alpine grasslands on the Qinghai-Tibetan Plateau is an important ecological pathway for returning organic matter and nutrients that are closely linked to soil fertility and grassland productivity. However, few previous studies have investigated the dynamics of carbon (C) and nitrogen (N) associated with yak dung pats, particularly with respect to C and N leaching. This study experimentally investigated the effects of yak dung pat fragmentation on its C and N dynamics in Northern Tibet. Four treatments were examined: a full-size dung pat (control, FDP) and respectively splitting the full-size dung pat into four (1/4FDP), eight (1/8FDP), and sixteen (1/16FDP) equal-sized pats, each within an identical leaching device and had three replicates. The results showed that fragmentation did not influence (P > 0.05) dung total organic C (TOC) and N (TN) concentrations, but it did cause a decrease (P < 0.05) in both ammonium-N (NH4+-N) and nitrate-N (NO3--N) concentrations and also reduced the loss of dry matter (P < 0.05), after 72 days of dung decomposition. Cumulative amounts of dissolved organic C (DOC) and N (DON) leached from the dung were significantly higher in the three fragmentation treatments than in the control (respectively 2.46-3.50 vs. 1.64 g C chamber(-1), 0.14-0.16 vs. 0.10 g N chamber(-1); P < 0.05). However, fragmentation did not always decrease cumulative dung NH4+-N and NO3--N leaching, and neither NH4+-N nor NO3--N leaching (P > 0.05) were affected by the 1/4FDP treatment. The DOC leaching accounted for 1.58-3.36 % of the initial dung TOC input, while the DON, NH4+-N, and NO3--N leaching respectively accounted for 2.34-3.82 %, 0.68-0.87 %, and 0.19-0.27 % of the initial dung TN input. In conclusion, our findings suggest that yak dung pat fragmentation can increase the leaching of DOC and DON and the heavily fragmenting can decrease the leaching of both NH4+-N and NO3--N after short-term dung decomposition in Northern Tibet. C1 [Du, Ziyin; Wu, Yong; Zhang, Bin] China West Normal Univ, Sch Land & Resources, Nanchong 637009, Peoples R China. [Du, Ziyin; Wang, Xiaodan; Yan, Yan] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Xiang, Jian] Nanjing Forestry Univ, Coll Forestry, Nanjing 210037, Peoples R China. [Zhang, Xiaoke] Hohai Univ, Sch Publ Adm, Nanjing 210098, Peoples R China. [Cai, Yanjiang] Zhejiang A&F Univ, State Key Lab Subtrop Silviculture, Hangzhou 311300, Peoples R China. RP Cai, YJ (通讯作者)，666 Wusu St, Hangzhou 311300, Peoples R China. EM yjcai@zafu.edu.cn TC 8 Z9 9 PD APR 15 PY 2021 VL 310 AR 107301 DI 10.1016/j.agee.2021.107301 EA JAN 2021 UT WOS:000615985000010 DA 2023-03-23 ER PT J AU Jiang, XJ Zhu, X Yuan, ZQ Li, XG Liu, WJ Zakari, S AF Jiang, Xiao-Jin Zhu, Xiai Yuan, Zi-Qiang Li, Xiao Gang Liu, Wenjie Zakari, Sissou TI Lateral flow between bald and vegetation patches induces the degradation of alpine meadow in Qinghai-Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Bald patches (BPs) are known to accelerate and simultaneously mitigate the process of desertification. However, the mechanisms of these two synchronous actions are little studied in high desert and cold systems; and the incidence of BPs on alpine meadows degradation in Qinghai-Tibetan Plateau (QTP) of China is still unavailable. This study first aims to investigate the soil properties and the erodibility of the system BPs-VPs at the Beiluhe basin in QTP. Then, we adopted dye tracer and HYDRUS-2/3D methods to interpret the water infiltration patterns from point scale to slope scale. The results show that the mattic epipedon layer on the top soil (0-20 cm) of VPs directly reduced the impact of raindrops on alpine meadow; and the adhesion of root system in VPs prevented the soil particles from stripping and washing away by runoff. The soil particles in BPs were easily eroded by rainfall, lowering the ground level of BPs relative to the ground level of VPs. The two patches therefore alternated to form an erosion interface where marginal meadow was likely detached by raindrops, and washed away through runoff. The saturated hydraulic conductivity (K-s) of surface soil (0-10 cm) was 124% higher in BPs than the VPs. Thereby, BPs caused a high spatial variation of infiltration and runoff in QTP. Moreover, this difference in K-s between the two patches conducted to a lateral flow from BPs to VPs, and to soil layers with different water contents. These findings highlight that the water flow features can potentially disturb the processes of freezing-thawing, frost heaves, and thaw slump; and accelerate the alpine meadow degradation. Therefore, land cover such as crop and vegetation should be applied over the bare soil surface to prevent the degradation of alpine meadow. (C) 2020 Elsevier B.V. All rights reserved. C1 [Jiang, Xiao-Jin; Zhu, Xiai; Liu, Wenjie; Zakari, Sissou] Chinese Acad Sci, Xishuangbanna Trop Bot Garden, CAS Key Lab Trop Forest Ecol, Menglun 666303, Yunnan, Peoples R China. [Jiang, Xiao-Jin; Zhu, Xiai; Liu, Wenjie; Zakari, Sissou] Chinese Acad Sci, Core Bot Gardens, Ctr Plant Ecol, Menglun 666303, Yunnan, Peoples R China. [Yuan, Zi-Qiang] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. [Li, Xiao Gang] Lanzhou Univ, Sch Life Sci, Inst Arid Agroecol, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Peoples R China. RP Liu, WJ; Zakari, S (通讯作者)，Chinese Acad Sci, Xishuangbanna Trop Bot Garden, CAS Key Lab Trop Forest Ecol, Menglun 666303, Yunnan, Peoples R China. EM lwj@xtbg.org.cn; sissouzakari@xtbg.ac.cn TC 13 Z9 13 PD JAN 10 PY 2021 VL 751 AR 142338 DI 10.1016/j.scitotenv.2020.142338 UT WOS:000587300800140 DA 2023-03-23 ER PT J AU Liu, YX Liu, SL Sun, YX Li, MQ An, Y Shi, FN AF Liu, Yixuan Liu, Shiliang Sun, Yongxiu Li, Mingqi An, Yi Shi, Fangning TI Spatial differentiation of the NPP and NDVI and its influencing factors vary with grassland type on the Qinghai-Tibet Plateau SO ENVIRONMENTAL MONITORING AND ASSESSMENT DT Article AB Grasslands are the dominant ecosystem of the Qinghai-Tibet Plateau (QTP), and they play an important role in climate regulation and represent an important ecological barrier in China. However, the spatial differentiation characteristics of net primary productivity (NPP) and normalized differential vegetation index (NDVI) and the main influencing factors that vary with grassland type on the QTP are not clear. In this study, standardized precipitation evapotranspiration index (SPEI), digital elevation model (DEM), precipitation, temperature, slope, photosynthetically active radiation (PAR) and grazing intensity were considered the driving factors. First, a grey relational degree analysis was performed to test for the quantitative relationships between NPP, NDVI and factors. Then, the geographical detector method was applied to analyze the interaction relationships of the factors. Finally, based on the geographically weighted regression (GWR) model, the influence of factors varied with grassland type on the NPP and NDVI was revealed from the perspective of spatial differentiation. The results were as follows: (1) The NPP and NDVI had roughly the same degrees of correlation with each impact factor by the grey relational degree analysis, each factor was closely related to the NPP and NDVI, and the relational degree between grazing intensity and NPP was greater than that between grazing intensity and NDVI. (2) The interaction relationships between influencing factors and NPP and NDVI varied with the grassland type and presented bivariate enhancement and nonlinear enhancement, and the interaction effects between grazing intensity and any factor on each grassland type had a greater impact on NPP. (3) The main influencing factors of the spatial heterogeneity of NPP were grazing intensity and PAR, which were "high from northeast to southwest, low from northwest to southeast" and "low in the middle and high around". The main influencing factors on the NDVI were precipitation and PAR, which were "low in the middle and high around" and "high in the north, low in the south". C1 [Liu, Yixuan; Liu, Shiliang; Sun, Yongxiu; Li, Mingqi; An, Yi; Shi, Fangning] Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. RP Liu, SL (通讯作者)，Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM shiliangliu@bnu.edu.cn TC 22 Z9 24 PD JAN 7 PY 2021 VL 193 IS 1 AR 48 DI 10.1007/s10661-020-08824-y UT WOS:000608021600006 DA 2023-03-23 ER PT J AU Gao, XX Dong, SK Xu, YD Fry, EL Li, Y Li, S Shen, H Xiao, JN Wu, SN Yang, MY Zhang, J Zhi, YL Liu, SL Shang, ZH Yeomans, JC AF Gao, Xiaoxia Dong, Shikui Xu, Yudan Fry, Ellen L. Li, Yu Li, Shuai Shen, Hao Xiao, Jiannan Wu, Shengnan Yang, Mingyue Zhang, Jing Zhi, Yangliu Liu, Shiliang Shang, Zhanhuan Yeomans, Jane C. TI Plant biomass allocation and driving factors of grassland revegetation in a Qinghai-Tibetan Plateau chronosequence SO LAND DEGRADATION & DEVELOPMENT DT Article AB Biomass allocation is a key factor in understanding how ecosystems respond to changing environmental conditions. The role of soil chemistry in the above- and belowground plant biomass allocation in restoring grassland is still incompletely characterized. Consequently, it has led to two competing hypotheses for biomass allocation: optimal partitioning, where the plants allocate biomass preferentially to optimize resource use; and the isometric hypothesis, which postulates that biomass allocation between roots and shoots is fixed. Here we tested these hypotheses over a chronosequence of alpine grasslandsion undergoing restoration in the Qinghai-Tibetan Plateau, these range from severely degraded to those with 18 years of revegetation with an intact grassland (as a reference). A high proportion of biomass was allocated to the roots in the revegetated grasslands, and more biomass to shoots in the degraded and intact grasslands. The grasslands gradually decreased their root to shoot ratio as revegetation continued, with the lowest value in year 18 of revegetation. Our results showed that aboveground biomass (AGB) was increased by available phosphorus (P), soil moisture, and negatively related to bulk density, while belowground biomass (BGB) was positively impacted by total P and negatively by nitrate nitrogen (N). The trade-off between them was positively associated with available P and nitrate-N, and soil nutrient availability is more linked to increased AGB relative to BGB. Our study indicates that biomass allocation is highly variable during the revegetation period from degraded grassland, and is linked with soil properties, thus supporting the optimal partitioning hypothesis. C1 [Gao, Xiaoxia; Dong, Shikui; Xu, Yudan; Li, Shuai; Shen, Hao; Xiao, Jiannan; Yang, Mingyue; Zhang, Jing; Zhi, Yangliu; Liu, Shiliang] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing, Peoples R China. [Dong, Shikui; Wu, Shengnan] Beijing Forestry Univ, Coll Grassland Sci, Beijing 100083, Peoples R China. [Gao, Xiaoxia; Fry, Ellen L.] Univ Manchester, Manchester, Lancs, England. [Li, Yu] Chongqing Technol & Business Univ, Sch Tourism & Land Resource, Chongqing 400067, Peoples R China. [Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, Sate Key Lab Grassland Agoecosyst, Lanzhou 730000, Peoples R China. [Yeomans, Jane C.] Earth Univ, Res Dept, San Jose, Costa Rica. RP Dong, SK (通讯作者)，Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. EM dongshikui@sina.com TC 5 Z9 5 PD FEB 28 PY 2021 VL 32 IS 4 BP 1732 EP 1741 DI 10.1002/ldr.3819 EA JAN 2021 UT WOS:000604889100001 DA 2023-03-23 ER PT J AU Chen, Y Liu, X Hou, YH Zhou, SR Zhu, B AF Chen, Ying Liu, Xiang Hou, Yanhui Zhou, Shurong Zhu, Biao TI Particulate organic carbon is more vulnerable to nitrogen addition than mineral-associated organic carbon in soil of an alpine meadow SO PLANT AND SOIL DT Article AB Background and aims Long-term nitrogen (N) addition can affect soil organic carbon (SOC) pool within different soil fractions with different turnover rates. However, the mechanisms of these effects, particularly in alpine grassland ecosystems, are not clear. Methods We studied the responses of SOC content in different soil fractions to N addition based on a six-year N addition field experiment in an alpine meadow ecosystem on the Tibetan Plateau. We measured soil chemical and microbial properties, and SOC content in bulk soil, particular organic matter (POM) and mineral-associated organic matter (MAOM) fractions in response to N addition. Results N addition increased soil N availability, decreased soil pH and microbial biomass, but had minimal effect on plant biomass, soil enzyme activity, and SOC content in bulk soil. With increasing levels of N addition, SOC in the POM fraction (POC) showed a significant negative trend, while SOC in the MAOM fraction (MAOC) did not change significantly. Conclusions As plant biomass input and soil enzyme activity were not significantly altered with N addition, the decline in POC was likely caused by changes in microbial physiology (carbon use efficiency), while the insignificant change in MAOC may be determined by the balance between input (from microbial necromass) and output (from microbial decomposition). Taken together, our study showed that the less-protected POC fraction is more vulnerable to N addition than the more-protected MAOC fraction in the alpine grassland. This finding may improve the prediction of soil C dynamics in response to N deposition in alpine grassland ecosystems on the Tibetan Plateau. C1 [Chen, Ying; Hou, Yanhui; Zhu, Biao] Peking Univ, Inst Ecol, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. [Chen, Ying; Hou, Yanhui; Zhu, Biao] Peking Univ, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China. [Liu, Xiang; Zhou, Shurong] Fudan Univ, Sch Life Sci, Key Lab Biodivers Sci & Ecol Engn, Minist Educ, Shanghai 200438, Peoples R China. RP Zhu, B (通讯作者)，Peking Univ, Inst Ecol, Coll Urban & Environm Sci, Beijing 100871, Peoples R China.; Zhu, B (通讯作者)，Peking Univ, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China. EM biaozhu@pku.edu.cn TC 20 Z9 25 PD JAN PY 2021 VL 458 IS 1-2 SI SI BP 93 EP 103 DI 10.1007/s11104-019-04279-4 UT WOS:000607876500007 DA 2023-03-23 ER PT J AU Liu, GM Wu, TH Hu, GJ Wu, XD Li, WP AF Liu, Guimin Wu, Tonghua Hu, Guojie Wu, Xiaodong Li, Wangping TI Permafrost existence is closely associated with soil organic matter preservation: Evidence from relationships among environmental factors and soil carbon in a permafrost boundary area SO CATENA DT Article AB Permafrost regions store a large amount of soil organic carbon (SOC). Although permafrost degradation with climate warming can stimulate soil organic matter (SOM) decomposition, it remains unknown that whether the permafrost existence benefits SOM preservation. Here, a boundary area of permafrost and non-permafrost zone was selected to test the hypothesis that SOM underlain by permafrost has been better preserved than the area without permafrost under similar climatic conditions. The interactions among topography, vegetation cover, permafrost, soil variables and SOC distribution were examined. The results showed the sites beneath wet meadow land covers, which are usually underlain by permafrost, have higher SOC stocks than those of alpine meadows without permafrost. Based on mixed effects models, both soil water content and bulk density explained higher SOC content variances in the sites without permafrost than the sites underlain by permafrost. The north-facing non-permafrost sites have significantly higher SOC contents than those in south-facing non-permafrost sites. Vegetation cover, aspect, and permafrost have mixing effects on SOC contents both in permafrost and nonpermafrost sites. Soil particle size and the rock fragment content are good predictors for prediction of SOC contents, while the best predictor was depending on the presence of permafrost. These results suggested that under similar climatic conditions, permafrost existence favors the preservation of SOM, this should be taken into consideration in the future carbon emission from permafrost regions since permafrost degradation can lag behind climate warming in many areas. C1 [Liu, Guimin] Lan Jiaotong Univ, Sch Environm & Municipal Engn, 88 West Anning Rd, Lanzhou 730070, Peoples R China. [Liu, Guimin; Wu, Tonghua; Hu, Guojie; Wu, Xiaodong] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, 320 West Donggang Rd, Lanzhou 730000, Peoples R China. [Li, Wangping] Lanzhou Univ Technol, Sch Civil Engn, 287 Langongping Rd, Lanzhou 730050, Peoples R China. [Wu, Tonghua] Southern Marine Sci & Engn Guangdong Lab Guangzho, Guangzhou 511458, Peoples R China. [Wu, Tonghua; Wu, Xiaodong] Univ Chinese Acad Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China. RP Liu, GM (通讯作者)，88 West Aiming Rd, Lanzhou 730070, Peoples R China.; Wu, XD (通讯作者)，320 West Donggang Rd, Lanzhou 730000, Peoples R China. EM liuguimin@mail.lzjtu.cn; wuxd@lzb.ac.cn TC 8 Z9 8 PD JAN PY 2021 VL 196 AR 104894 DI 10.1016/j.catena.2020.104894 UT WOS:000583955200052 DA 2023-03-23 ER PT J AU Ma, PP Qin, Y Fu, H Wang, LY Yan, ZY Ma, WW Li, XL Niu, DC AF Ma, Panpan Qin, Yan Fu, Hua Wang, Liya Yan, Zhenying Ma, Wenwen Li, Xilai Niu, Decao TI Effects of Grassland Degradation on the Distribution and Stability of Water-Stable Aggregate on the Qinghai-Tibet Plateau SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES DT Article AB The maintenance and stability of soil structures are critical for the stability of alpine grassland ecosystems. To elucidate how soil structures are altered by the degradation of alpine grasslands, this study investigated the various characteristics of soil aggregate particle sizes, and associated interactions with soil variables and soil stability in lightly, moderately, and severely degraded alpine steppes and meadows in Tianjun County, Qinghai Province, China. The results revealed that grassland degradation culminated in the modification of soil particle sizes from macro-aggregates (2-0.25 mm) to micro aggregates (0.25-0.053 mm), to silt + clay fractions (<0.053 mm), and the stability of soil aggregates decreased. Moreover, the finer particle size grade might more clearly reflect soil disaggregation processes. Soil organic carbon (SOC), soil total nitrogen (STN), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) contents of both alpine steppes and alpine meadows significantly decreased with the worsening of grassland degradation. However, the microbial entropy carbon (qMBC) hardly changed, whereas the microbial entropy nitrogen (qMBN) of the severely degraded alpine steppes and alpine meadows were significantly higher than their counterparts in lightly and moderately degraded grasslands. Redundancy analysis (RDA) revealed that SOC, STN, MBC and MBN were positively correlated with the 2-1 mm fraction and the mean weight diameter (MWD) in both the alpine steppes and alpine meadows, but negatively correlated with the 0.25-0.1 mm fraction in the alpine steppes, and the <0.053 mm fraction in the alpine meadows. Structural equation model (SEM) results revealed that SOC and STN were the critical factors affecting the composition and stability of soil aggregates. C1 [Ma, Panpan; Fu, Hua; Niu, Decao] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. [Ma, Panpan; Fu, Hua; Niu, Decao] Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China. [Ma, Panpan; Fu, Hua; Niu, Decao] Lanzhou Univ, Engn Res Ctr Grassland Ind, Minist Educ, Lanzhou 730020, Peoples R China. [Ma, Panpan; Fu, Hua; Niu, Decao] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. [Ma, Panpan; Li, Xilai] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Qin, Yan] Qinghai Univ, Acad Anim & Vet Sci, Qinghai Acad Anim Sci & Vet Med, Key Lab Super Forage Germplasm Qinghai Tibetan Pl, Xining 810016, Peoples R China. [Wang, Liya; Yan, Zhenying; Ma, Wenwen] Qinghai Prov Geog Situat Monitoring Inst, Xining 810008, Qinghai, Peoples R China. RP Niu, DC (通讯作者)，Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China.; Niu, DC (通讯作者)，Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China.; Niu, DC (通讯作者)，Lanzhou Univ, Engn Res Ctr Grassland Ind, Minist Educ, Lanzhou 730020, Peoples R China.; Niu, DC (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. EM xiaocao0373@163.com TC 1 Z9 2 PY 2021 VL 30 IS 3 BP 2671 EP 2689 DI 10.15244/pjoes/128580 UT WOS:000668149800001 DA 2023-03-23 ER PT J AU Xu, YD Dong, SK Gao, XX Yang, MY Li, S Shen, H Xiao, JN Han, YH Zhang, J Li, Y Zhi, YL Yang, YF Liu, SL Dong, QM Zhou, HK AF Xu, Yudan Dong, Shikui Gao, Xiaoxia Yang, Mingyue Li, Shuai Shen, Hao Xiao, Jiannan Han, Yuhui Zhang, Jing Li, Yu Zhi, Yangliu Yang, Yunfeng Liu, Shiliang Dong, Quanming Zhou, Huakun TI Aboveground community composition and soil moisture play determining roles in restoring ecosystem multifunctionality of alpine steppe on Qinghai-Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Alpine steppe is one of the most important grassland ecosystems on Qinghai-Tibetan Plateau (QTP), which has been greatly degraded in past decades. However, few studies have paid attention to the ecosystem multifunctionality (EMF) of restored degraded alpine steppes. Four treatments of alpine steppes (degraded alpine steppes, cultivated alpine steppes, fenced alpine steppes and intact alpine steppes) were investigated to explore the effect of treatment, biotic (above- and belowground community composition) and abiotic factors (pH and soil moisture) on restoring nine ecosystem functions (above- and belowground plant biomass, plant nitrogen content, soil organic carbon, soil nitrogen, soil phosphorus, soil microbial biomass carbon, microbial biomass nitrogen and microbial biomass phosphorus) and EMF of alpine steppe ecosystem in Madoi County of Qinghai Province, China. Our results showed that both grassland cultivation and fencing significantly promoted EMF of the degraded alpine steppes. Aboveground plant community composition was more significantly correlated with EMF of the alpine steppes than belowground soil community composition in the process of ecological restoration. Combining abiotic factors with biotic factors could improve the ability to explain EMF than biotic factors alone. Overall, aboveground community composition and soil moisture played determining roles in restoring EMF of alpine steppes. C1 [Xu, Yudan; Dong, Shikui; Gao, Xiaoxia; Yang, Mingyue; Li, Shuai; Shen, Hao; Xiao, Jiannan; Han, Yuhui; Zhang, Jing; Li, Yu; Zhi, Yangliu; Liu, Shiliang] Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. [Dong, Shikui] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. [Yang, Yunfeng] Tsinghua Univ, Sch Environm, Beijing 100084, Peoples R China. [Dong, Quanming] Qinghai Univ, Qinghai Acad Anim Husb & Vet Sci, Xining 810003, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining 810008, Peoples R China. RP Dong, SK (通讯作者)，Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. EM dongshikui@sina.com TC 18 Z9 18 PD JAN 1 PY 2021 VL 305 AR 107163 DI 10.1016/j.agee.2020.107163 UT WOS:000583328300004 DA 2023-03-23 ER PT J AU Yuan, ZQ Jiang, XJ AF Yuan, Zi-Qiang Jiang, Xiao-Jin TI Vegetation and soil covariation, not grazing exclusion, control soil organic carbon and nitrogen in density fractions of alpine meadows in a Tibetan permafrost region SO CATENA DT Article AB The accrual of soil organic carbon (SOC) and nitrogen (N) in grassland is an important management option to improve the ecosystem functions of grassland. However, how abiotic (such as grazing exclusion (GE)) and biotic factors influence SOC and N and their different fractions in Tibetan alpine meadows remains unclear. In this study, we evaluated the relative importance of abiotic and biotic factors that drive SOC and N contents in soil density fractions by performing redundancy analysis based on three long-term (10 years) fenced alpine meadows maintained in the permafrost region of the Tibetan Plateau in China. Biotic factors comprise plant aboveground biomass, cover and diversity, whereas abiotic factors include soil properties (i.e. soil moisture, pH, clay, silt, sand, total phosphorus, available phosphorus, microbial biomass carbon and N, available N, C:N ratio and C:P ratio) and GE. Site rather than GE has significant effects on the SOC and N contents. GE caused no increase in the SOC and N contents in the whole soil and fractions. Redundancy analysis showed that 96.7% of the variations in SOC and N fractions can be explained by the selected explanatory variables. Aboveground biomass, cover, soil moisture and clay contents were key factors that affected the SOC and N fractions. The SOC and N fractions were mainly explained by the interaction between vegetation and soil, followed by soil, vegetation and GE. The study highlighted the importance of considering the covariation of vegetation and soil for evaluating the SOC and N dynamics in alpine meadows. The effect of GE (such as 10 years) on the SOC and N contents in alpine meadows can be weak in the permafrost region of the Tibetan Plateau. C1 [Yuan, Zi-Qiang] Lanzhou Univ, Sch Life Sci, Inst Arid Agroecol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Yuan, Zi-Qiang] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. [Jiang, Xiao-Jin] Chinese Acad Sci, CAS Key Lab Trop Forest Ecol, Xishuangbanna Trop Bot Garden, Menglun 666303, Yunnan, Peoples R China. [Jiang, Xiao-Jin] Chinese Acad Sci, Ctr Plant Ecol, Core Bot Gardens, Menglun 666303, Yunnan, Peoples R China. RP Yuan, ZQ (通讯作者)，Lanzhou Univ, Sch Life Sci, Inst Arid Agroecol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China.; Yuan, ZQ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. EM yuanzq@lzb.ac.cn TC 8 Z9 9 PD JAN PY 2021 VL 196 AR 104832 DI 10.1016/j.catena.2020.104832 UT WOS:000583955200020 DA 2023-03-23 ER PT J AU Zhang, Y Ganjurjav, H Dong, SK Gao, QZ AF Zhang, Yong Ganjurjav, Hasbagan Dong, Shikui Gao, Qingzhu TI Excessive plant compensatory growth: a potential endogenous driver of meadow degradation on the Qinghai-Tibetan Plateau SO ECOSYSTEM HEALTH AND SUSTAINABILITY DT Article AB Degradation of meadow ecosystems in the largest alpine region of the world, i.e., the Qinghai-Tibetan Plateau (QTP), is a crucial ecological issue that has ardently discussed in recent years. Many factors, such as livestock overgrazing, climate change and overpopulation of small mammals are treated as important factors that cause the degradation of meadow ecosystems in the QTP. However, there are few hypotheses focus on the potential role of plant compensatory growth on meadow degradation. We proposed a compensatory growth-related hypothesis to understand the potential degradation process of meadow ecosystems in the QTP. We discussed that there are two stages of meadow degradation, i.e. the beginning stage of meadow degradation that is triggered by high-strength overcompensation; and the intensification stage of meadow degradation, which are driven by external factors such as climate warming, small mammals and thawing of permafrost.The mechanism of meadow degradation driven by plant compensatory growth is the asynchronism of plant consumption and the availability of soil nutrients. Our hypothesis that plant compensatory growth drives meadow degradation under the overgrazing condition requires re-examination and modification by testing the balance between soil nutrient cycling rates and the strength of plant compensatory growth in alpine regions. C1 [Zhang, Yong] Southwest Forestry Univ, Coll Wetlands, Natl Plateau Wetlands Res Ctr, Kunming, Yunnan, Peoples R China. [Ganjurjav, Hasbagan; Gao, Qingzhu] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. [Dong, Shikui] Beijing Forestry Univ, Sch Grassland Sci, Beijing, Peoples R China. RP Zhang, Y (通讯作者)，300 Bailongsi, Kunming 650224, Yunnan, Peoples R China.; Ganjurjav, H (通讯作者)，12thZhongguancun South St, Beijing 100081, Peoples R China. EM zhy1902@126.com; ganjurjav@foxmail.com TC 4 Z9 5 PD DEC 16 PY 2020 VL 6 IS 1 AR 1816500 DI 10.1080/20964129.2020.1816500 UT WOS:000587329000001 DA 2023-03-23 ER PT J AU Zhao, XQ Zhao, L Xu, TW Xu, SX AF Zhao, Xinquan Zhao, Liang Xu, Tianwei Xu, Shixiao TI The plateau pika has multiple benefits for alpine grassland ecosystem in Qinghai-Tibet Plateau SO ECOSYSTEM HEALTH AND SUSTAINABILITY DT Editorial Material AB The plateau pika (Ochotona curzoniae) has been engaged in pest control for many years based on the logic that the plateau pika is responsible for alpine grassland degradation and competes with livestock for forage resources. However, the plateau pika is an important species which has multiple benefits in Qinghai-Tibetan plateau, as it (i) makes burrows that are the primary homes for lizards and a variety of small birds; (ii) creates microhabitat disturbance that promotes the increase of plant species richness; (iii) serves as the principal prey for almost all of the plateau predator species; and (iv) contributes positively to the dynamic equilibrium of alpine ecosystems. C1 [Zhao, Xinquan; Zhao, Liang; Xu, Tianwei; Xu, Shixiao] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. RP Zhao, XQ (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. EM xqzhao@nwipb.cas.cn TC 9 Z9 10 PD DEC 16 PY 2020 VL 6 IS 1 AR 1750973 DI 10.1080/20964129.2020.1750973 UT WOS:000533628400001 DA 2023-03-23 ER PT J AU Yan, YL Wan, ZQ Ganjurjav, H Yang, J Hu, GZ Gao, QZ Zou, JF Liu, GP Quan, W Wen, L AF Yan, Yulong Wan, Zhiqiang Ganjurjav, Hasbagan Yang, Jie Hu, Guozheng Gao, Qingzhu Zou, Jiefu Liu, Guoping Quan, Wei Wen, Lin TI Nitrogen deposition reduces methane uptake in both the growing and non-growing season in an alpine meadow SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Nitrogen (N) deposition-induced N input in alpine meadow soils may affect the soil exchange of methane (CH4) with the atmosphere. The quantities and spatiotemporal variation in CH4 uptake remain largely unknownfor this ecosystem on a global scale. Previous studies regarding CH4 flux have mainly focused on the growing season in alpine meadows. Thus, the impact of N deposition on the non-growing season uptake of CH4 is unknown. In this study, we investigated the effects of N deposition on CH4 uptake during both the growing and non-growing seasons in an alpine meadow on the central Qinghai-Tibet Plateau (QTP). The CH4 fluxes were measured using static chambers and gas chromatography in four N deposition treatment areas (Control; N7, 7 kg N ha(-1) yr(-1); N20, 20 kg N ha(-1) yr(-1); N40, 40 kg N ha(-1) yr(-1)) fromMay 2015 to August 2018. Our results showed that alpine meadowsoils acted as CH4 sinks throughout the year. N deposition significantly decreased CH4 uptake fluxes (P < 0.05) and the annual mean CH4 uptake fluxes declined at N deposition levels of 7, 20, and 40 kg N ha(-1) yr(-1) by 12.3%, 14.4%, and 20.5%, respectively, comparedwith that of the control. Annual CH4 uptake was significantly correlated with total annual precipitation, mean annual air temperature, and N deposition rate. Annual cumulative CH4 uptake in the four treatments across 3 years was 75.1 mg C m(-2), where approximately 40% of the total annual CH4 uptake occurred during the non-growing season. Our results showed that CH4 uptake in the non-growing season cannot be ignored when estimating annual uptake of CH4 because of the large CH4 uptake during the non-growing season in the alpine meadow on the QTP under N deposition conditions. (C) 2020 Elsevier B.V. All rights reserved. C1 [Yan, Yulong; Yang, Jie] Inner Mongolia Univ, Sch Ecol & Environm, Hohhot 010021, Peoples R China. [Wan, Zhiqiang] Inner Mongolia Normal Univ, Coll Geog Sci, Hohhot 010020, Peoples R China. [Yan, Yulong; Ganjurjav, Hasbagan; Hu, Guozheng; Gao, Qingzhu] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Yang, Jie] Inner Mongolia Univ Finance & Econ, Hohhot 010051, Peoples R China. [Zou, Jiefu] China Energy Conservat & Environm Protect Grp, Beijing 100082, Peoples R China. [Yan, Yulong; Liu, Guoping; Quan, Wei; Wen, Lin] China New Era Grp Corp, Beijing 100034, Peoples R China. RP Yang, J (通讯作者)，Inner Mongolia Univ, Sch Ecol & Environm, Hohhot 010021, Peoples R China.; Ganjurjav, H (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China.; Yang, J (通讯作者)，Inner Mongolia Univ Finance & Econ, Hohhot 010051, Peoples R China. EM ganjurjav@foxmail.com; yangjie@imu.edu.cn TC 3 Z9 3 PD DEC 10 PY 2020 VL 747 AR 141315 DI 10.1016/j.scitotenv.2020.141315 UT WOS:000579386300085 DA 2023-03-23 ER PT J AU Wang, ZQ Bu, HY Wang, MC Huang, H Niklas, KJ AF Wang, Zhiqiang Bu, Haiyan Wang, Mingcheng Huang, Heng Niklas, Karl J. TI Allocation Strategies for Seed Nitrogen and Phosphorus in an Alpine Meadow Along an Altitudinal Gradient on the Tibetan Plateau SO FRONTIERS IN PLANT SCIENCE DT Article AB Nitrogen (N) and phosphorus (P) play important roles in many aspects of plant biology. The allocation of N and P in plant vegetative organs (i.e., leaves, stems, and fine roots) is critical to the regulation of plant growth and development. However, how these elements are allocated in seeds is unclear. The aim of this study was to explore the N and P allocation strategies of seeds in an alpine meadow along an altitudinal gradient. We measured the seed N and P contents of 253 herbaceous species in 37 families along an altitudinal gradient (2,000-4,200 m) in the east Tibetan alpine meadow. The geometric means of seed N and P concentrations and N:P ratios were 34.81 mg g(-1), 5.06 mg g(-1), and 6.88, respectively. Seed N and P concentrations varied across major taxonomic groups and among different altitude zones. N:P ratios showed no significant variations among different taxonomic groups with the exception of N-fixing species. The numerical value of the scaling exponent of seed N vs. P was 0.73, thus approaching 3/4, across the entire data set, but varied significantly across major taxonomic groups. In addition, the numerical value of the scaling exponent of N vs. P declined from 0.88 in the high altitude zone to 0.63 in the low altitude zone. These results indicate that the variations in the numerical value of the scaling exponent governing the seed N vs. P scaling relationship varies as a function of major taxonomic groups and among different altitude zones. We speculate that this variation reflects different adaptive strategies for survival and germination in an alpine meadow. If true, the data presented here advance our understanding of plant seed allocation strategies, and have important implications for modeling early plant growth and development. C1 [Wang, Zhiqiang; Wang, Mingcheng] Chengdu Univ, Inst Adv Study, Chengdu, Peoples R China. [Bu, Haiyan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. [Huang, Heng] Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. [Niklas, Karl J.] Cornell Univ, Sch Integrat Plant Sci, Plant Biol Sect, Ithaca, NY USA. RP Huang, H (通讯作者)，Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. EM henghuang@berkeley.edu TC 6 Z9 6 PD DEC 9 PY 2020 VL 11 AR 614644 DI 10.3389/fpls.2020.614644 UT WOS:000600961300001 DA 2023-03-23 ER PT J AU Jiang, X Ai, SH Yang, SQ Zhu, MK Ai, YW Ai, XY Yang, JY Huang, CM AF Jiang, Xue Ai, Shenghao Yang, Siqian Zhu, Mengke Ai, Yingwei Ai, Xiaoyan Yang, Jingyan Huang, Chengmin TI Effects of Different Highway Slope Disturbance on Soil Bulk Density, pH, and Soil Nutrients SO ENVIRONMENTAL ENGINEERING SCIENCE DT Article AB Soil is inevitably affected by highway construction, resulting in a large volume of bare soil exposed to degradation. As an increasingly important and demanding area, identifying and assessing soil quality and stability on highway slopes are important for ecological management. In this study, principal component analysis, clustering analysis, and integrated matter-element model were used to evaluate the effects of highway slopes (embankment slopes [ES] and cutting slopes [CS]) on soil nutrients in the Qinghai-Tibet Plateau using grassland soil (GS) and natural slopes (NS) as controls. Our results show that, compared to NS, soil pH was significantly higher under GS, while ES and CS had no significant effect. Compared with NS, soil total nitrogen (TN) results for ES and CS recorded declines of 26.58% and 40.77%, respectively; TN increased by 263.04% in GS. Compared with NS, soil total phosphorus results declined by 25.44%, 34.37%, and 11.45% in GS, ES, and CS, respectively. Our results suggest that bare soil on highway slopes can be prone to degradation over time, and they have a negative effect on the accumulation of nitrogen and phosphorus in the soil nutrient status of slopes in the Qinghai-Tibet Plateau. Findings from this study will increase current understanding of soil nutrient responses to slope disturbance for high-cold highway slopes. C1 [Jiang, Xue; Yang, Siqian; Zhu, Mengke; Ai, Yingwei; Ai, Xiaoyan] Sichuan Univ, State Key Lab Hydraul & Mt River Engn, Key Lab Bioresource & Ecoenvironm, Minist Educ,Coll Life Sci, 24,South Sect 1, Chengdu 610065, Peoples R China. [Ai, Shenghao] Sichuan Normal Univ, Coll Chem & Mat Sci, Chengdu, Peoples R China. [Yang, Jingyan; Huang, Chengmin] Sichuan Univ, Coll Architecture & Environm, Chengdu, Peoples R China. RP Ai, YW (通讯作者)，Sichuan Univ, State Key Lab Hydraul & Mt River Engn, Key Lab Bioresource & Ecoenvironm, Minist Educ,Coll Life Sci, 24,South Sect 1, Chengdu 610065, Peoples R China. EM aiyw99@sohu.com TC 1 Z9 1 PD APR 1 PY 2021 VL 38 IS 4 BP 256 EP 265 DI 10.1089/ees.2020.0125 EA DEC 2020 UT WOS:000598374300001 DA 2023-03-23 ER PT J AU Wu, JQ Wang, HY Li, G Ma, WW Wu, JH Gong, Y Xu, GR AF Wu, Jiangqi Wang, Haiyan Li, Guang Ma, Weiwei Wu, Jianghua Gong, Yu Xu, Guorong TI Vegetation degradation impacts soil nutrients and enzyme activities in wet meadow on the Qinghai-Tibet Plateau SO SCIENTIFIC REPORTS DT Article AB Vegetation degradation, due to climate change and human activities, changes the biomass, vegetation species composition, and soil nutrient input sources and thus affects soil nutrient cycling and enzyme activities. However, few studies have focused on the responses of soil nutrients and enzymes to vegetation degradation in high-altitude wet meadows. In this study, we examined the effects of vegetation degradation on soil nutrients (soil organic carbon, SOC; total nitrogen, TN; total phosphorus, TP) and enzyme activities (i.e., urease, catalase, amylase) in an alpine meadow in the eastern margin of the Qinghai-Tibet Plateau. Four different levels of degradation were defined in terms of vegetation density and composition: primary wet meadow (CK), lightly degraded (LD), moderately degraded (MD), and heavily degraded (HD). Soil samples were collected at depth intervals of 0-10, 10-20, 20-40, 40-60, 60-80, and 80-100 cm to determine soil nutrient levels and enzyme activities. The results showed that SOC, TN, catalase and amylase significantly decreased with degradation level, while TP and urease increased with degradation level (P<0.05). Soil nutrient and enzyme activity significantly decreased with soil depth (P<0.05), and the soil nutrient and enzyme activity exhibited obvious "surface aggregation". The activities of soil urease and catalase were strongest in spring and weakest in winter. The content of TN in spring, summer, and autumn was significantly higher than observed in winter (P<0.05). The soil TP content increased in winter. Soil amylase activity was significantly higher in summerm than in spring, autumn, and winter (P<0.05). TP was the main limiting factor for plant growth in the Gahai wet meadow. Values of SOC and TN were positively and significantly correlated with amylase and catalase (P<0.05), but negatively correlated with urease (P<0.05). These results suggest the significant role that vegetation degradation and seasonal freeze-thaw cycle play in regulating enzyme activities and nutrient availability in wet meadow soil. C1 [Wu, Jiangqi; Wang, Haiyan; Li, Guang; Ma, Weiwei; Xu, Guorong] Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China. [Wu, Jianghua; Gong, Yu] Mem Univ Newfoundland, Sch Sci & Environm, 20 Univ Dr, Corner Brook, AB A2H 5G4, Canada. RP Li, G (通讯作者)，Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China.; Wu, JH (通讯作者)，Mem Univ Newfoundland, Sch Sci & Environm, 20 Univ Dr, Corner Brook, AB A2H 5G4, Canada. EM 1462528657@qq.com; jwu@grenfell.mun.ca TC 26 Z9 29 PD DEC 4 PY 2020 VL 10 IS 1 AR 21271 DI 10.1038/s41598-020-78182-9 UT WOS:000608856300035 DA 2023-03-23 ER PT J AU Li, CX de Jong, R Schmid, B Wulf, H Schaepman, ME AF Li, Chengxiu de Jong, Rogier Schmid, Bernhard Wulf, Hendrik Schaepman, Michael E. TI Changes in grassland cover and in its spatial heterogeneity indicate degradation on the Qinghai-Tibetan Plateau SO ECOLOGICAL INDICATORS DT Article AB Arid grassland ecosystems undergo degradation because of increasing environmental and human pressures. Degraded grasslands show vegetation cover reduction and soil-patch development, leading to grassland fragmentation and changes in spatial heterogeneity. Understanding grassland degradation that involves soil-patch development remains a challenge over large areas with limited accessibility such as the Qinghai-Tibetan Plateau. We hypothesized that vegetation cover, its spatial heterogeneity and changes thereof over time retrieved from satellite data can indicate grassland development and degradation levels. To test the hypothesis, we studied these indicators from 2000 to 2016 and related them to previously described degradation levels on the eastern Qinghai-Tibetan Plateau (QTP) in 2004. We further use these indicators to map the new grassland development and degradation levels in 2016. We found that lower vegetation cover does not always indicate a more severe degradation; instead, higher spatial heterogeneity is a better correlate of degradation. Combined temporal changes in grassland cover and its spatial heterogeneity are related to the literature-defined degradation levels. We found that grassland areas on the eastern QTP have moved into new degradation stages from 2000 to 2016 using changes in grassland cover and its spatial heterogeneity as indicators. The normalized difference vegetation index (NDVI) as a proxy for grassland cover declined over time in the literature-defined degraded areas but increased in the desert areas from 2000 to 2016. Spatial heterogeneity generally increased across different degradation levels from 2000 to 2016; however, this increase was less pronounced in severely degraded and slightly deserted areas. Our newly defined degradation levels in 2016 included degradation, desertification, and improving levels. Across our study area, 63% of all areas were classified as degraded and 2% were at risk of desertification. The remaining areas (35%) classified as improving and re-growing occurred in higher-elevation or previously severely degraded grassland. Our study demonstrates that a combination of changes in grassland cover and in its spatial heterogeneity can indicate grassland degradation levels and serve as an early-warning signal for desertification threats. C1 [Li, Chengxiu; de Jong, Rogier; Schmid, Bernhard; Wulf, Hendrik; Schaepman, Michael E.] Univ Zurich, Remote Sensing Labs, Winterthurerstr 190, CH-8057 Zurich, Switzerland. RP Li, CX (通讯作者)，Univ Zurich, Remote Sensing Labs, Winterthurerstr 190, CH-8057 Zurich, Switzerland. EM chengxiu.li@geo.uzh.ch TC 21 Z9 22 PD DEC PY 2020 VL 119 AR 106641 DI 10.1016/j.ecolind.2020.106641 UT WOS:000579817600004 DA 2023-03-23 ER PT J AU Li, JS Shao, XQ Huang, D Shang, JY Liu, KS Zhang, Q Yang, XM Li, H He, YX AF Li, Jinsheng Shao, Xinqing Huang, Ding Shang, Jianying Liu, Kesi Zhang, Qian Yang, Xiaomeng Li, Hui He, Yixuan TI The addition of organic carbon and nitrogen accelerates the restoration of soil system of degraded alpine grassland in Qinghai-Tibet Plateau SO ECOLOGICAL ENGINEERING DT Article AB Soil degradation is often accompanied with the decrease of soil organic matter and soil fertility, and the direct addition of organic carbon and nitrogen could be the good method to accelerate the restoration of soil system of degraded grassland. The effects of the addition of biochar and nitrogen on soil properties and microorganisms in the 0-20 cm soil depth of degraded alpine grassland were evaluated. The treatments consisted of three different levels of biochar (1 kg m(-2), 2 kg m(-2), and 4 kg m(-2)) and nitrogen (5 g m(-2), 10 g m(-2), 15 g m(-2)). The addition of biochar and nitrogen increased soil organic carbon, total nitrogen, available phosphorus, water content (SWC), urease, phosphatase,and microbial biomass. The relative content of arbuscular mycorrhizal fungi, 18:1w9c fungi, actinomycetes, gram-negative and gram-positive bacteria increased, however, 18:2w6,9c fungi, anaerobic bacteria and methanotrophic bacteria decreased. Under the effect of biochar and nitrogen addition, most of soil physicochemical properties showed significant correlation in the 0-20 cm soil layer. The correlation between microbial community and soil properties mainly occurred in the 0-10 cm soil layer. The community of fungi, actinomycetes, gram-negative and Gram-positive bacteria showed significant relationship with soil urease, phosphatase, and available phosphorus (P < 0.01, r > 0.30). Arbuscular mycorrhizal fungi showed strong positive correlation with pH, NH4+, and SWC. These results indicated that the addition of biochar and nitrogen quickly improved soil nutrient and microbial community of degraded alpine grassland and could be used for the remediation of degraded alpine grassland. C1 [Li, Jinsheng; Shao, Xinqing; Huang, Ding; Liu, Kesi; Zhang, Qian; Yang, Xiaomeng; Li, Hui; He, Yixuan] China Agr Univ, Coll Grassland Sci & Technol, Beijing 100193, Peoples R China. [Shang, Jianying] China Agr Univ, Dept Water & Soil Sci, Beijing 100193, Peoples R China. [Liu, Kesi] Natl Field Stn Grassland Ecosyst Guyuan, Guyuan 076550, Hebei, Peoples R China. RP Liu, KS (通讯作者)，China Agr Univ, Coll Grassland Sci & Technol, Beijing 100193, Peoples R China. EM kliu@cau.edu.cn TC 12 Z9 14 PD DEC 1 PY 2020 VL 158 AR 106084 DI 10.1016/j.ecoleng.2020.106084 UT WOS:000596367600006 DA 2023-03-23 ER PT J AU Liu, M Wang, Y Sun, J Zhang, ZC Xu, XL Zhou, HK Wu, GL Xu, M Tsunekawa, A Haregeweyn, N Tsubo, M AF Liu, Miao Wang, Yi Sun, Jian Zhang, Zhenchao Xu, Xingliang Zhou, Huakun Wu, Gao-lin Xu, Ming Tsunekawa, Atsushi Haregeweyn, Nigussie Tsubo, Mitsuru TI Shift in nurse effect from facilitation to competition with increasing size of Salix cupularis canopy in a desertified alpine meadow on the Tibetan Plateau SO CATENA DT Article AB The Tibetan Plateau is among the most ecologically important and sensitive regions worldwide, which has undergone severe desertification in recent decades, particularly in the Zoige region. In an effort to stem the progression of desertification, shrubs such as Salix cupularis have been planted in some localities in this region. However, the mechanisms whereby the interspecific relationships between these shrubs and the undergrowth vegetation change in response to an increase in shrub canopy area remain unclear. In this study, we examined the traits of plant communities and analysed soil samples under S. cupularis in a degraded alpine meadow along a gradient of four different canopy areas (1.3-1.8, 3.8-5.5, 12.6-14.5, and 27.3-28.3 m(2)). Our results revealed that plant community characteristics shifted from facilitation to competition at a canopy area of 3.8-5.5 m(2). However, changes in soil nutrients and the activities of sucrase and catalase were not detected until the canopy area of S. cupularis had reached 2.6-14.5 m(2). Furthermore, we found that microbial communities, particularly bacteria, showed trends similar to those shown by soil properties. In line with expectations, we found that the soil fungal community showed trends opposite to those shown by the bacterial community. Our findings highlight that competition rather than facilitation tends to be the predominant interspecific relationship that develops in response to the continued growth of nurse plants. Consequently, these results provide evidence in support of the stress-gradient hypothesis, which states that interspecific competition is particularly prevalent in fertile environments, particularly when there are changes in facilitation during periods of increasing environmental stress. Importantly, with respect to the shift in interspecific relationships from facilitative to competitive, we demonstrate that the response of the belowground interactions was slower than that of interactions above ground. Collectively, our observations indicate that the nurse effect of S. cupularis on ecosystems could have significant implications for the restoration of desertified grasslands. C1 [Liu, Miao; Wang, Yi; Sun, Jian; Zhang, Zhenchao; Xu, Xingliang; Xu, Ming] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. [Liu, Miao; Tsunekawa, Atsushi; Tsubo, Mitsuru] Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Reg Qinghai, Xining 810008, Peoples R China. [Wu, Gao-lin] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Haregeweyn, Nigussie] Tottori Univ, Int Platform Dryland Res & Educ, Tottori 6800001, Japan. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. EM liumiao@igsnrr.ac.cn; mrwy201314@163.com; sunjian@igsnrr.ac.cn; zhenchaozhang0626@163.com; hkzhou@nwipb.cas.cn; mingxu@igsnrr.ac.cn; tsunekawa@tottori-u.ac.jp; tsubo@tottori-u.ac.jp TC 7 Z9 8 PD DEC PY 2020 VL 195 AR 104757 DI 10.1016/j.catena.2020.104757 UT WOS:000580366300019 DA 2023-03-23 ER PT J AU Liu, X Wang, YB Yang, WJ Lv, MX Zhao, HP AF Liu, Xin Wang, Yibo Yang, Wenjing Lv, Mingxia Zhao, Haipeng TI Effects of freezing-thawing cycle on the daily evapotranspiration of alpine meadow soil in Qinghai-Tibet Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB The study of the diurnal response mechanism of the actual evapotranspiration (ETa) to the environment in the permafrost regions of the Qinghai-Tibet Plateau (QTP) using the LYS30 micro-evaporation instrument found that there are different feedbacks to the ETa under freezing and thawing cycles. The ETa process during the winter cooling period (WC) and the spring warming period (SW) is snow and ice sublimation and is mainly affected by the vapour pressure deficit (VPD). In the summer thawing period (ST), ETa can reach the maximum value when all meteorological elements reach a certain range of change at the same time, while ETa will decrease when the meteorological elements are not qualified. During the autumn freezing period (AF), the amount of condensate reached a maximum at 7:00, and due to the sudden change in meteorological elements at 9:00, the ETa increased rapidly at a rate higher than the condensation rate that occurred between 7:00 and 9:00. We also found that in different stages of freezing and thawing, the two physical processes of condensation and evaporation alternated in 1 day, with the process of evaporation occurring during the day and the condensation process occurring during the night. The diurnal response mechanism of the ETa to the environment in the permafrost regions of the QTP is expected to reveal the mechanism of soil hydrological processes and will provide a theoretical and scientific basis for water balance analysis and ecological environment protection in permafrost regions. C1 [Liu, Xin; Wang, Yibo; Yang, Wenjing; Lv, Mingxia; Zhao, Haipeng] Lanzhou Univ, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Minist Educ, Lanzhou 730000, Peoples R China. RP Wang, YB (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Minist Educ, Lanzhou 730000, Peoples R China. EM wangyib@lzu.edu.cn TC 4 Z9 4 PD DEC PY 2020 VL 79 IS 24 AR 533 DI 10.1007/s12665-020-09290-y UT WOS:000594337400001 DA 2023-03-23 ER PT J AU Liu, YW Tenzintarchen Geng, XD Wei, D Dai, DX Xu-Ri AF Liu, Yongwen Tenzintarchen Geng, Xiaodong Wei, Da Dai, Dongxue Xu-Ri TI Grazing exclusion enhanced net ecosystem carbon uptake but decreased plant nutrient content in an alpine steppe SO CATENA DT Article AB Grazing exclusion is widely conducted to restore degraded grasslands. The recovery status can be indicated by both nutrient and carbon cycling. However, the effect of grazing exclusion on net ecosystem CO2 exchange and mineral nutrients in pastures on the Tibetan Plateau remains unclear, due to a lack of in situ investigations. Here, we conducted an in situ investigation of the grazing exclusion effect on net ecosystem CO2 exchange and foliar mineral elements in an alpine steppe on the central Tibetan Plateau. Our results show that seven years of grazing exclusion enhanced net CO2 uptake by 17% during the growing season via increased gross ecosystem photosynthesis, rather than unchanged ecosystem respiration. Grazing exclusion reduced the sensitivity of ecosystem respiration to soil surface temperature by 16-17% at both diurnal and seasonal scales. Grazing exclusion, therefore, may be an effective way to enhance carbon sequestration under the background of a warming climate. We further found that grazing exclusion significantly decreased the soil available nitrate-nitrogen concentration by 50% and foliar mineral concentrations such as nitrogen, calcium, sulfur, iron, and manganese. Grazing exclusion increased the foliar carbon:nitrogen ratio by 16% and decreased the foliar nitrogen:phosphorus ratio by 15%. These results indicate that grazing exclusion enhanced net ecosystem CO2 uptake but aggravated mineral nutrient limitation of plant growth. Our study highlights that grazing exclusion influences alpine grassland carbon cycling by directly preventing grazing and by indirectly altering the status of plant nutrients. A quantitative distinction of such direct and indirect effects based on long-term and continuous in situ field observations is critical for revealing the mechanism underlying carbon-nutrient cycling evolution in the restoration of degraded alpine grasslands. C1 [Liu, Yongwen; Xu-Ri] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, 16 Lincui Rd, Beijing 100101, Peoples R China. [Liu, Yongwen; Xu-Ri] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Tenzintarchen] Tibet Acad Agr & Anim Husb Sci, Inst Pratacultural Sci, Lhasa 850000, Peoples R China. [Geng, Xiaodong] Anqing Normal Univ, Sch Resources & Environm, Anqing 246133, Peoples R China. [Wei, Da] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Dai, Dongxue] Hebei Normal Univ Nationalities, Coll Biol & Food Sci, Chengde 067000, Peoples R China. RP Liu, YW; Xu-Ri (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, 16 Lincui Rd, Beijing 100101, Peoples R China. EM liuyongwen@itpcas.ac.cn; xu-ri@itpcas.ac.cn TC 11 Z9 11 PD DEC PY 2020 VL 195 AR 104799 DI 10.1016/j.catena.2020.104799 UT WOS:000580366300046 DA 2023-03-23 ER PT J AU Peng, F Zhang, WJ Li, CY Lai, CM Zhou, J Xue, X Tsunekawa, A AF Peng, Fei Zhang, Wenjuan Li, Chengyang Lai, Chimin Zhou, Jun Xue, Xian Tsunekawa, Atsushi TI Sustained increase in soil respiration after nine years of warming in an alpine meadow on the Tibetan Plateau SO GEODERMA DT Article AB Soil microbes are key determinants of soil carbon (C) dynamics. The response of the soil microbial community to climate warming modulates the feedback between ecosystem C cycling and future climate change. We conducted a long-term manipulative warming (1.6 degrees C increase of the soil temperature at 5 cm) experiment to examine the soil respiration, microbial biomass, and community composition at an alpine meadow site on the Qinghai-Tibetan Plateau. After nine years of warming, soil respiration (3.5 mu mol m(2) s(-1) in control in the growing season) increased in the warmed plots. In the early growing season, the increase in heterotrophic respiration (R-h) accounted for more than 90% of the increase in soil respiration. The warming effect gradually decreased during the mid and late growing season (46%). Microbial biomass C and nitrogen declined significantly in the 0-10 cm to the 30-50 cm layer. Warming did not significantly affect microbial biomass C and N in any soil depth layer. Metabolic activity of microbes in terms of Rh per unit microbial biomass C significantly increased by 66% in warmed plots. The bacterial and fungal community composition did not significantly change in the warmed plots. The relative abundance of Actinobacteria decreased at 20-30 cm and 30-50 cm soil depths, but that of Cercozoa increased in all four soil layers. The relative Actinobacteria abundance was negatively correlated with R-h and metabolic activity in the 10-20 and 20-30 cm layers. Our results indicate a decrease in Actinobacteria abundance, increases in metabolic activity, and no substrate limitation sustained the positive warming effect on soil respiration throughout the last 9 years. This implies that climate warming could trigger a substantial loss of soil C to the atmosphere in the alpine meadow on the Qinghai-Tibet Plateau. C1 [Peng, Fei; Zhang, Wenjuan; Li, Chengyang; Lai, Chimin; Xue, Xian] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. [Peng, Fei] Tottori Univ, Int Platform Dryland Res & Educ, Tottori, Japan. [Peng, Fei; Xue, Xian] Chinese Acad Sci, Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Beijing, Peoples R China. [Zhang, Wenjuan; Li, Chengyang; Lai, Chimin] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhou, Jun] Chinese Acad Sci, Inst Mt Hazards & Environm, Beijing, Peoples R China. [Tsunekawa, Atsushi] Tottori Univ, Arid Land Res Ctr, Tottori, Japan. RP Peng, F (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. EM pengfei@lzb.ac.cn TC 7 Z9 8 PD DEC 1 PY 2020 VL 379 AR 114641 DI 10.1016/j.geoderma.2020.114641 UT WOS:000580657200018 DA 2023-03-23 ER PT J AU Song, MH Cornelissen, JHC Li, YK Xu, XL Zhou, HK Cui, XY Wang, YF Xu, RY Feng, Q AF Song, Ming-Hua Cornelissen, Johannes H. C. Li, Yi-Kang Xu, Xing-Liang Zhou, Hua-Kun Cui, Xiao-Yong Wang, Yan-Fen Xu, Rong-Yan Feng, Qi TI Small-scale switch in cover-perimeter relationships of patches indicates shift of dominant species during grassland degradation SO JOURNAL OF PLANT ECOLOGY DT Article AB Aims Grasslands are globally threatened by climate changes and unsustainable land-use, which often cause transitions among alternative stable states, and even catastrophic transition to desertification. Spatial vegetation patch configurations have been shown to signify such transitions at large spatial scale. Here, we demonstrate how small-scale patch configurations can also indicate state transitions. Methods The whole spatial series of degradation successions were chosen in alpine grasslands characterized as seven typical communities. Patch numbers, and perimeter and cover of each patch were recorded using adjacent quadrats along transects in each type of the communities. Species abundance within each patch was measured. Important Findings Across seven grazing-induced degradation stages in the world's largest expanse of grassland, from dense ungrazed turf to bare black-soil crust, patch numbers and perimeters first increased as patch cover decreased. Numbers and perimeters then decreased rapidly beyond an intersection point at 68% of initial continuous vegetation cover. Around this point, the vegetation fluctuated back and forth between the sedge-dominated grassland breaking-up phase and the forb-dominated phase, suggesting impending shift of grassland state. This study thus demonstrates how ground-based small-scale vegetation surveys can provide a quantitative, easy-to-use signals for vegetation degradation, with promise for detecting the catastrophic transition to desertification. C1 [Song, Ming-Hua; Xu, Xing-Liang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Song, Ming-Hua; Li, Yi-Kang; Zhou, Hua-Kun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining 810008, Peoples R China. [Cornelissen, Johannes H. C.] Vrije Univ Amsterdam, Fac Earth & Life Sci, Dept Ecol Sci, Syst Ecol, Boelelaan 1085, NL-1081 HV Amsterdam, Netherlands. [Cui, Xiao-Yong; Wang, Yan-Fen] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Xu, Rong-Yan] Shanghai Chenshan Bot Garden, Shanghai Key Lab Plant Funct Genom & Res, Plant Sci Res Ctr, Shanghai 201602, Peoples R China. [Feng, Qi] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Ecohydrol Inland River Basin, Lanzhou 730000, Peoples R China. RP Song, MH (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China.; Song, MH; Li, YK (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining 810008, Peoples R China. EM songmh@igsnrr.ac.cn; ykli@nwipb.cas.cn TC 6 Z9 6 PD DEC PY 2020 VL 13 IS 6 BP 704 EP 712 DI 10.1093/jpe/rtaa057 UT WOS:000593099700005 DA 2023-03-23 ER PT J AU Teng, YM Zhan, JY Agyemang, FB Sun, YX AF Teng, Yanmin Zhan, Jinyan Agyemang, Frank Boappeah Sun, Yongxiu TI The effects of degradation on alpine grassland resilience: A study based on meta-analysis data SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Alpine grasslands on the Qinghai-Tibet Plateau (QTP) provide irreplaceable ecosystem services to local and global communities. However, intensive human activities have caused severe grassland degradation during recent decades. Due to the harsh environment, these degraded grasslands recover slowly or may be irrecoverable after they degenerate to a certain stage. To understand the changes in the resilience of alpine grassland on the QTP after degradation, we evaluated the resilience indexes of the plant, soil and plant-soil systems of grasslands at different degradation stages based on an integrated assessment system and data extracted from 53 published studies in this region. The results showed that,with grassland degradation, most plant indicators including plant height, aboveground biomass, belowground biomass, Cyperaceae, Gramineae, and soil indicators including silt, clay, soil organic carbon, soil total nitrogen, available nitrogen, available phosphorus, available potassium, and soil water content gradually decreased; soil variables including sand, bulk density, and soil temperature showed an increasing trend; and Margalef richness index, Shannon-Wiener index, Pielou evenness index, and forbs first increased and then decreased. The resilience indexes of the plant, soil and plant-soil systems all displayed an obvious downward trend with the increase of degradation degree, which indicates that reduction of grassland resilience is the coordinated degeneration of vegetation and soil. To restore degraded grassland, we should focus on improving both soil and vegetation status to enhance the resilience of grassland ecosystems. (C) 2020 The Author(s). Published by Elsevier B.V. C1 [Teng, Yanmin; Zhan, Jinyan; Agyemang, Frank Boappeah; Sun, Yongxiu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. RP Zhan, JY (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM zhanjy@bnu.edu.cn TC 15 Z9 15 PD DEC PY 2020 VL 24 AR e01336 DI 10.1016/j.gecco.2020.e01336 UT WOS:000608479300025 DA 2023-03-23 ER PT J AU Zhang, W Yi, SH Qin, Y Sun, Y Shangguan, DH Meng, BP Li, M Zhang, JG AF Zhang, Wei Yi, Shuhua Qin, Yu Sun, Yi Shangguan, Donghui Meng, Baoping Li, Meng Zhang, Jianguo TI Effects of Patchiness on Surface Soil Moisture of Alpine Meadow on the Northeastern Qinghai-Tibetan Plateau: Implications for Grassland Restoration SO REMOTE SENSING DT Article AB Surface soil moisture (SSM) is a key limiting factor for vegetation growth in alpine meadow on the Qinghai-Tibetan Plateau (QTP). Patches with various sizes and types may cause the redistribution of SSM by changing soil hydrological processes, and then trigger or accelerate alpine grassland degradation. Therefore, it is vital to understand the effects of patchiness on SSM at multi-scales to provide a reference for alpine grassland restoration. However, there is a lack of direct observational evidence concerning the role of the size and type of patches on SSM, and little is known about the effects of patches pattern on SSM at plot scale. Here, we first measured SSM of typical patches with different sizes and types at patch scale and investigated their patterns and SSM spatial distribution through unmanned aerial vehicle (UAV)-mounted multi-type cameras at plot scale. We then analyzed the role of the size and type of patchiness on SSM at both patch and plot scales. Results showed that: (1) in situ measured SSM of typical patches was significantly different (P < 0.01), original vegetation patch (OV) had the highest SSM, followed by isolate vegetation patch (IV), small bare patch (SP), medium bare patch (MP) and large bare patch (LP); (2) the proposed method based on UAV images was able to estimate SSM (0-40 cm) with a satisfactory accuracy (R-2 = 0.89, P < 0.001); (3) all landscape indices of OV, with the exception of patch density, were positively correlated with SSM at plot scale, while most of the landscape indices of LP and IV showed negative correlations (P < 0.05). Our results indicated that patchiness intensified the spatial heterogeneity of SSM and potentially accelerated the alpine meadow degradation. Preventing the development of OV into IV and the expansion of LP is a critical task for alpine meadow management and restoration. C1 [Zhang, Wei; Qin, Yu; Shangguan, Donghui] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, 320 Donggang West Rd, Lanzhou 730000, Peoples R China. [Zhang, Wei] Univ Chinese Acad Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China. [Yi, Shuhua; Sun, Yi; Meng, Baoping; Li, Meng; Zhang, Jianguo] Nantong Univ, Sch Geog Sci, Inst Fragile Ecosyst & Environm, 999 Tongjing Rd, Nantong 226007, Peoples R China. RP Yi, SH (通讯作者)，Nantong Univ, Sch Geog Sci, Inst Fragile Ecosyst & Environm, 999 Tongjing Rd, Nantong 226007, Peoples R China. EM zhangwei2015@lzb.ac.cn; yis@ntu.edu.cn; qiny@lzb.ac.cn; sunyi@ntu.edu.cn; dhguan@lzb.ac.cn; mengbp09@lzu.edu.cn; limeng@ntu.edu.cn; sezjg@ntu.edu.cn TC 8 Z9 9 PD DEC PY 2020 VL 12 IS 24 AR 4121 DI 10.3390/rs12244121 UT WOS:000603253600001 DA 2023-03-23 ER PT J AU Li, JH Cheng, BH Zhang, R Li, WJ Shi, XM Han, YW Ye, LF Ostle, NJ Bardgett, RD AF Li, Jin Hua Cheng, Bing Heng Zhang, Rui Li, Wen Jin Shi, Xiao Ming Han, Yong Wei Ye, Lu Feng Ostle, Nicholas J. Bardgett, Richard D. TI Nitrogen and phosphorus additions accelerate decomposition of slow carbon pool and lower total soil organic carbon pool in alpine meadows SO LAND DEGRADATION & DEVELOPMENT DT Article AB Nitrogen (N) and phosphorus (P) additions reduced soil organic carbon (SOC) contents and stocks in alpine meadows on the Tibetan Plateau. However, little is known about microbial mechanisms behind SOC decline. This study investigated the effects of long-term N and P additions on microbial community composition and SOC decomposition (C mineralization (C-m), mean resistant times for active C pool (MRTa), and slow C pool (MRTs) in alpine meadows. Results showed that the total SOC pool was reduced by 2-9% under N and P additions, of which slow C pool decreased by 3-10%, while active C pool increased by 4-75% compared to the Control. N and P additions shortened MRTs by 34-40% but prolonged MRTa by 30-62%. The relative abundance of four bacterial families was related to C-m or MRTa, while that of most of the fungal families affected SOC decomposition (including C-m, MRTa, and MRTs). N and P additions increased fungal diversity, differentially affected microbial community composition and structure through modifying microbial preference, and increasing the abundance of microbes which are capable of decomposing complex carbohydrate. Soil pH, available N, and total P were main factors determining microbial abundances. Microbial changes due to N and P additions accelerated decomposition of recalcitrant SOC, thus led to declines in slow C pool and total SOC pool but increases in active C pool. Therefore, long-term N and P additions weaken soil functioning as C pool in alpine meadows. C1 [Li, Jin Hua; Cheng, Bing Heng; Zhang, Rui; Li, Wen Jin; Shi, Xiao Ming; Ye, Lu Feng] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Han, Yong Wei; Ye, Lu Feng] Chinese Res Inst Environm Sci, Beijing, Peoples R China. [Ostle, Nicholas J.] Univ Lancaster, Lancaster Environm Ctr, Lancaster, England. [Bardgett, Richard D.] Univ Manchester, Sch Earth & Environm Sci, Manchester, Lancs, England. RP Li, JH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. EM lijinhuap@sohu.com TC 15 Z9 16 PD FEB 28 PY 2021 VL 32 IS 4 BP 1761 EP 1772 DI 10.1002/ldr.3824 EA NOV 2020 UT WOS:000594417200001 DA 2023-03-23 ER PT J AU Shen, H Dong, SK DiTommaso, A Li, S Xiao, JN Yang, MY Zhang, J Gao, XX Xu, YD Zhi, YL Liu, SL Dong, QM Wang, WY Liu, P Xu, JY AF Shen, Hao Dong, Shikui DiTommaso, Antonio Li, Shuai Xiao, Jiannan Yang, Mingyue Zhang, Jing Gao, Xiaoxia Xu, Yudan Zhi, Yangliu Liu, Shiliang Dong, Quanming Wang, Wenying Liu, Pan Xu, Jiyu TI Eco-physiological processes are more sensitive to simulated N deposition in leguminous forbs than non-leguminous forbs in an alpine meadow of the Qinghai-Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Increased nitrogen (N) deposition can affect ecosystem processes and thus influence plant eco-physiological processes in grasslands. However, how N deposition affects eco-physiological processes of leguminous and non-leguminous forbs in alpine grasslands is understudied. A long-term field experiment using a range of simulated N deposition rates (0, 8, 24, 40. 56, and 72 kg N ha(-1) year(-1)) was established to examine the effects of N deposition on various eco-physiological parameters in leguminous and non-leguminous forbs in an alpine meadow of the Qinghai-Tibetan Plateau. We found that the responses of leguminous and non-leguminous forbs to simulated N deposition varied. Net photosynthetic rate of leguminous and non-leguminous forbs exhibited different response patterns, but chronic increases in simulated N deposition rates may lead to negative effects in both functional groups. Neither functional group responded differently in aboveground biomass under the highest N addition level (72 kg N ha(-1) year(-1)) compared to the control. Differences in aboveground biomass of leguminous forbs were observed at intermediate N levels. Short-term simulated N deposition significantly promoted N uptake of both functional groups. In leguminous forbs, simulated N deposition affected net photosynthetic rates (P-N) and aboveground biomass (AGB) mainly via stomatal conductance (gs), water use efficiency (WUE), and plant N uptake. In non-leguminous forbs, simulated N deposition affected P-N and AGB mainly through WUE and plant N uptake. Our findings suggest that leguminous and non-leguminous forbs have differential response mechanisms to N deposition, and compared with non-leguminous forbs, leguminous forbs are more sensitive to continuing increased N deposition. The obvious decline trend in photosynthetic capacity in leguminous forbs is likely to exacerbate the already divergent ecological processes between leguminous and non-leguminous forbs. More importantly, these changes are likely to alter the future composition, function, and stability of alpine meadow ecosystems. (C) 2020 Published by Elsevier B.V. C1 [Shen, Hao; Dong, Shikui; Li, Shuai; Xiao, Jiannan; Yang, Mingyue; Zhang, Jing; Gao, Xiaoxia; Xu, Yudan; Zhi, Yangliu; Liu, Shiliang] Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. [Dong, Shikui] Beijing Forestry Univ, Coll Grassland Sci, Beijing 100083, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. [Shen, Hao; DiTommaso, Antonio] Cornell Univ, Sch Integrat Plant Sci, Soil & Crop Sci, Ithaca, NY 14853 USA. [Dong, Quanming] Qinghai Univ, Qinghai Acad Anim Husb & Vet Sci, Xining 810003, Peoples R China. [Wang, Wenying; Liu, Pan; Xu, Jiyu] Qinghai Normal Univ, Sch Life & Geog Sci, Xining 810008, Peoples R China. RP Dong, SK (通讯作者)，Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. EM dongshikui@sina.com TC 8 Z9 10 PD NOV 20 PY 2020 VL 744 AR 140612 DI 10.1016/j.scitotenv.2020.140612 UT WOS:000573748900001 DA 2023-03-23 ER PT J AU Li, JH Zhang, R Cheng, BH Ye, LF Li, WJ Shi, XM AF Li, Jin Hua Zhang, Rui Cheng, Bing Heng Ye, Lu Feng Li, Wen Jin Shi, Xiao Ming TI Effects of nitrogen and phosphorus additions on decomposition and accumulation of soil organic carbon in alpine meadows on the Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Nitrogen (N) and phosphorus (P) additions to grasslands increase aboveground plant biomass and modify plant community composition, thereby affecting plant-derived organic carbon (C) input to soil and soil C cycling and storage. However, the effects of N and P additions on soil organic C (SOC) decomposition and sequestration are not fully understood and their underlying mechanisms are poorly known. This study aimed to explore the mechanisms underlying SOC decomposition and SOC content decline in the topsoil of alpine meadows on the Tibetan Plateau after 9-years of field N and P additions. Stoichiometric characteristics of soil and microorganisms and their effects on microbial decomposition, including priming effects (PEs), C substrates decomposition, and microbial C use efficiency (CUE), were investigated by adding C-13 labeled substrate (glucose or vanillin). Results showed that N and P additions differentially affected the magnitude and direction of PEs and SOC decomposition, accelerated mineralization of glucose and vanillin by 33-45% and 11-45%, respectively, but decreased microbial CUE of glucose and vanillin by 9-15% and 11-48%, respectively. These effects were caused by differential increase in microbial activity and acceleration of microbial decomposition due to N and P additions, and induced lower soil ecological stoichiometric ratios and higher microbial C:N:P ratios. The above effects led to different magnitudes of decomposition and accumulation of SOC and plant-derived C substrate and thus decline in SOC content depending on N and P additions. We found that long-term N and P additions would weaken soil functioning as a C pool for alpine meadows on the Tibetan Plateau. C1 [Li, Jin Hua; Zhang, Rui; Cheng, Bing Heng; Ye, Lu Feng; Li, Wen Jin; Shi, Xiao Ming] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. RP Li, JH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. EM lijinhuap@sohu.com TC 12 Z9 13 PD FEB 15 PY 2021 VL 32 IS 3 BP 1467 EP 1477 DI 10.1002/ldr.3792 EA NOV 2020 UT WOS:000590028300001 DA 2023-03-23 ER PT J AU Liu, GY Xie, CW Zhao, L Xiao, Y Wu, TH Wang, W Liu, WH AF Liu, Guangyue Xie, Changwei Zhao, Lin Xiao, Yao Wu, Tonghua Wang, Wu Liu, Wenhui TI Permafrost warming near the northern limit of permafrost on the Qinghai-Tibetan Plateau during the period from 2005 to 2017: A case study in the Xidatan area SO PERMAFROST AND PERIGLACIAL PROCESSES DT Article AB Permafrost that exists near the boundary of the permafrost zone is generally more sensitive to climate change. By analyzing ground temperatures observed from two 30-m-deep boreholes, a case study was conducted to present some characteristics of recent permafrost warming in the Xidatan area, near the northern limit of the permafrost zone on the Qinghai-Tibetan Plateau. The rate of permafrost degradation from top to bottom in the area was far less than that from bottom to top. Local conditions produced spatial differences in permafrost characteristics, and thus the site covered by alpine meadow had a thinner active layer and lower rate of change than the site with desert steppe. With permafrost warming, the depths of zero annual amplitude at the two sites showed significant decreasing trends, suggesting that the warming could change the proportion of unfrozen water and ice in permafrost, and then lead to a decrease in the mean thermal diffusivity of formation. Mean annual permafrost temperatures at depth of zero annual amplitude of the two boreholes were respectively 0.4 and -0.7 degrees C, indicating that high-temperature permafrost is widely distributed in the study area. The lower temperature permafrost had a higher warming rate and a higher upward shift rate of the permafrost base. The pattern of permafrost degradation near the limit of permafrost was characterized by nonuniform speed and staged development. C1 [Liu, Guangyue; Xie, Changwei; Xiao, Yao; Wu, Tonghua; Wang, Wu] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Xizang Plateau, Lanzhou 730000, Peoples R China. [Liu, Guangyue; Zhao, Lin] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhao, Lin] Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing, Peoples R China. [Liu, Wenhui] Qinghai Univ, Dept Geol Engn, Xining, Peoples R China. RP Xie, CW (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Xizang Plateau, Lanzhou 730000, Peoples R China. EM xiecw@lzb.ac.cn TC 8 Z9 9 PD JUL PY 2021 VL 32 IS 3 BP 323 EP 334 DI 10.1002/ppp.2089 EA NOV 2020 UT WOS:000589945700001 DA 2023-03-23 ER PT J AU Zhang, ZC Liu, M Sun, J Wei, TX AF Zhang, Zhenchao Liu, Miao Sun, Jian Wei, Tianxing TI Degradation leads to dramatic decrease in topsoil but not subsoil root biomass in an alpine meadow on the Tibetan Plateau, China SO JOURNAL OF ARID LAND DT Article AB Understanding the effects of degradation on belowground biomass (BGB) is essential for assessment of carbon budget of the alpine meadow ecosystem on the Tibetan Plateau, China. This ecosystem has been undergoing serious degradation owing to climate change and anthropogenic activities. This study examined the response of the vertical distribution of plant BGB to degradation and explored the underlying mechanisms in an alpine meadow on the Tibetan Plateau. A field survey was conducted in an alpine meadow with seven sequential degrees of degradation in the Zoige Plateau on the Tibetan Plateau during the peak growing season of 2018. We measured aboveground biomass (AGB), BGB, soil water content (SWC), soil bulk density (SBD), soil compaction (SCOM), soil organic carbon (SOC), soil total nitrogen (STN), soil total phosphorus (STP), soil available nitrogen (SAN), and soil available phosphorus (STP) in the 0-30 cm soil layers. Our results show that degradation dramatically decreased the BGB in the 0-10 cm soil layer (BGB(0-10)) but slightly increased the subsoil BGB. The main reason may be that the physical-chemical properties of surface soil were more sensitive to degradation than those of subsoil, as indicated by the remarked positive associations of the trade-off value of BGB(0-10) with SWC, SCOM, SOC, STN, SAN, and STP, as well as the negative correlation between the trade-off value of BGB(0-10) and SBD in the soil layer of 0-10 cm. In addition, an increase in the proportion of forbs with increasing degradation degree directly affected the BGB vertical distribution. The findings suggest that the decrease in the tradeoff value of BGB(0-10) in response to degradation might be an adaptive strategy for the degradation-induced drought and infertile soil conditions. This study can provide theoretical support for assessing the effects of degradation on the carbon budget and sustainable development in the alpine meadow ecosystem on the Tibetan Plateau as well as other similar ecosystems in the world. C1 [Zhang, Zhenchao; Liu, Miao; Sun, Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. [Zhang, Zhenchao] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Liu, Miao] Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. [Wei, Tianxing] Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing 100083, Peoples R China. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. EM sunjian@igsnrr.ac.cn TC 7 Z9 10 PD SEP PY 2020 VL 12 IS 5 BP 806 EP 818 DI 10.1007/s40333-020-0074-x EA NOV 2020 UT WOS:000588887100002 DA 2023-03-23 ER PT J AU Huang, CH Peng, F You, QG Liao, J Duan, HC Wang, T Xue, X AF Huang, Cuihua Peng, Fei You, Quangang Liao, Jie Duan, Hanchen Wang, Tao Xue, Xian TI The Response of Plant and Soil Properties of Alpine Grassland to Long-Term Exclosure in the Northeastern Qinghai-Tibetan Plateau SO FRONTIERS IN ENVIRONMENTAL SCIENCE DT Article AB Currently, grazing exclosure is one of the most important grassland management measures for restoring all types of degraded alpine grassland in the Qinghai-Tibetan Plateau (QTP). The most widely distributed grassland ecosystems across the northeastern QTP are the alpine meadow (AM), alpine meadow steppe (AMS), and alpine steppe (AS). However, whether the impacts of fencing on vegetation characteristics and soil properties vary among different grassland types remains poorly understood despite that numerous individual studies have been conducted. This study investigated the vegetation characteristics and soil properties in fenced and grazed AM, AMS, and AS in the northeastern QTP. Grazing exclosure significantly increased the vegetation coverage and Shannon-Wiener diversity index in all the three grasslands. Plant species richness was significantly increased in AM, but there were no significant changes in AMS and AS. Aboveground biomass was significantly increased in AMS and AS but not significant in AM. Increase in the percentage of high-quality forage grasses was only observed in AMS. Fencing significantly decreased the soil bulk density (BD) and significantly increased soil organic carbon (SOC) and total nitrogen at a depth of 0-50 cm in AMS and AS but had no effect in AM. Our results indicate that the use of fencing for restoring degraded AM might not achieve the same expected results as in AS and AMS on the QTP. C1 [Huang, Cuihua; Peng, Fei; You, Quangang; Liao, Jie; Duan, Hanchen; Wang, Tao; Xue, Xian] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Drylands Salinizat Res Stn, Lanzhou, Peoples R China. RP Xue, X (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Drylands Salinizat Res Stn, Lanzhou, Peoples R China. EM xianxue@lzb.ac.cn TC 2 Z9 2 PD NOV 12 PY 2020 VL 8 AR 589104 DI 10.3389/fenvs.2020.589104 UT WOS:000592230400001 DA 2023-03-23 ER PT J AU Han, X Li, YH Du, XF Li, YB Wang, ZW Jiang, SW Li, Q AF Han, Xu Li, Yuhui Du, Xiaofang Li, Yingbin Wang, Zhengwen Jiang, Siwei Li, Qi TI Effect of grassland degradation on soil quality and soil biotic community in a semi-arid temperate steppe SO ECOLOGICAL PROCESSES DT Article AB Grasslands provide a number of ecosystem services for human society. Degradation of grasslands results in the loss of biodiversity and leads to the deterioration of ecosystem functions. In order to accurately assess the influence of grassland degradation on belowground ecosystems, we conducted experiments on a temperate steppe with different levels of degradation and investigated the influence of degradation on soil quality and soil biotic communities. Our results showed that grassland degradation significantly decreased soil quality, with lower values of soil quality index (SQI) observed in the degraded grassland than the meadow steppe and the grassland from the forest-steppe ecotone. Changes in the SQI along the grassland degradation gradient were positively correlated with soil carbon stock and the aboveground biomass, and negatively correlated with the root shoot ratio. Nematode trophic diversity and the ratio of fungal to bacterial PLFA were lower in the degraded grassland than the grassland from the forest-steppe ecotone. The dissimilarities in soil microbial and nematode community composition increased with the changes in soil quality index. Our results indicate that soil quality index based on the minimum data sets could effectively assess the influence of grassland degradation on soil biodiversity and ecosystem function. In order to effectively restore degraded grasslands, the key contributors to the soil quality, such as soil carbon, should be taken on priority basis for revitalizing the soil biodiversity and ecosystem function. C1 [Han, Xu; Li, Yuhui; Du, Xiaofang; Li, Yingbin; Wang, Zhengwen; Jiang, Siwei; Li, Qi] Chinese Acad Sci, Inst Appl Ecol, Erguna Forest Steppe Ecotone Res Stn, Shenyang 110016, Peoples R China. [Han, Xu; Li, Yuhui; Du, Xiaofang] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Li, Q (通讯作者)，Chinese Acad Sci, Inst Appl Ecol, Erguna Forest Steppe Ecotone Res Stn, Shenyang 110016, Peoples R China. EM liq@iae.ac.cn TC 12 Z9 14 PD NOV 11 PY 2020 VL 9 IS 1 AR 63 DI 10.1186/s13717-020-00256-3 UT WOS:000593938900001 DA 2023-03-23 ER PT J AU Dai, LC Yuan, YM Guo, XW Du, YG Ke, X Zhang, FW Li, YK Li, Q Lin, L Zhou, HK Cao, GM AF Dai, Licong Yuan, Yiming Guo, Xiaowei Du, Yangong Ke, Xun Zhang, Fawei Li, Yikang Li, Qian Lin, Li Zhou, Huakun Cao, Guangmin TI Soil water retention in alpine meadows under different degradation stages on the northeastern Qinghai-Tibet Plateau SO JOURNAL OF HYDROLOGY DT Article AB Alpine meadow degradation has become serious in recent decades due to the combined effects of overgrazing, human activities and rodents, but very few studies focus on the possible impact of alpine meadow degradation on soil water retention on the Qinghai-Tibet Plateau. In this study, four degradation stages (non-degradation, ND; light degradation, LD; moderate degradation, MD; heavy degradation, HD) were selected. Results showed that (1) the aboveground biomass decreased with increasing degradation, while the belowground biomass first increased and then decreased with a maximum value in MD. (2) As the degree of degradation increased from ND to MD, the 0-10 cm soil bulk density (BD) and soil compaction (SC) decreased with the minimum values in MD (0.61 g cm(-3) for BD and 1619.51 kPa for SC), while soil organic matter (SOM) increased with maximum value in MD (247.36 g kg(-1)), the 0-10 cm SOM in MD was the 1.5 times of that in ND. However, the 0-10 cm particle size distribution did not change significantly with increasing degradation, while the 20-40 cm clay content in HD was significantly higher than those of the other three degradation stages, (3) The MD stage displayed a strong water holding capacity in 0-10 cm soil layer due to its higher soil organic matter induced by the thick mattic epipedon. Meanwhile, the water holding capacity in the HD stage was higher than that of the other three degradation stages in the 20-40 cm soil layer owing to its higher capillary porosity. Furthermore, the soil water retention was greatly affected by the mattic epipdon through its effects on soil properties such as reducing BD and increasing SOM. Our results suggested that the mattic epipdon may play a crucial role in water retention in alpine ecosystems. C1 [Dai, Licong; Guo, Xiaowei; Du, Yangong; Ke, Xun; Zhang, Fawei; Li, Yikang; Li, Qian; Lin, Li; Zhou, Huakun; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810001, Qinghai, Peoples R China. [Dai, Licong; Guo, Xiaowei; Du, Yangong; Ke, Xun; Zhang, Fawei; Li, Yikang; Li, Qian; Lin, Li; Zhou, Huakun; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Qinghai, Peoples R China. [Dai, Licong; Ke, Xun] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Yuan, Yiming] Nanjing Agr Univ, Coll Resources & Environm Sci, Jiangsu Key Lab Low Carbon Agr & GHGs Mitigat, Nanjing, Peoples R China. RP Guo, XW; Cao, GM (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810001, Qinghai, Peoples R China. EM xwguo1206@163.com; ygdu@nwipb.cas.cn TC 18 Z9 21 PD NOV PY 2020 VL 590 AR 125397 DI 10.1016/j.jhydrol.2020.125397 UT WOS:000599754500124 DA 2023-03-23 ER PT J AU Dong, SK Li, Y Ganjurjav, H Gao, QZ Gao, XX Zhang, J Yan, YL Zhang, Y Liu, SL Hu, GZ Wang, XX Wu, HB Li, S AF Dong, Shikui Li, Yu Ganjurjav, Hasbagan Gao, Qingzhu Gao, Xiaoxia Zhang, Jing Yan, Yulong Zhang, Yong Liu, Shiliang Hu, Guozheng Wang, Xuexia Wu, Hongbao Li, Shuai TI Grazing promoted soil microbial functional genes for regulating C and N cycling in alpine meadow of the Qinghai-Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Microbial functional genes can reflect the nutrient cycle activities in soil, because they encode various enzymes involved in the material cycle. Therefore, the gene abundance variation can reveal the impact of interference on the material cycle of grassland. To study the cycle of carbon (C), nitrogen (N) and phosphorus (P) between plant and soil in grassland under different grazing regimes, we investigated the soil microbial functional genes related to C, N, and P cycling by high-throughput quantitative PCR and 16S rRNA-based Illumina sequencing analysis under grazing exclusion (GE), rotational grazing (RG), and continuous grazing (CG) in alpine meadow of the Qinghai-Tibetan Plateau, where climate is characterized by little rain and low temperature, and grassland is very sensitive to grazing. The results showed at the early grazing period, C fixtion (rbcL, korA, and frdA) and lignin degradation (abfA, xylA, exg, lig, exoPG, chiA, and glx) processes were slower under GE; CH4 metabolism (mcrA) was faster under CG; RG and CG improved the denitrification process (narG); RG slowed down organic-P mineralization (phoD). At the late grazing period, C fixation (accA and frdA) and degradation (mnp, apu, and amyA) processes were slower under GE; CH4 metabolism (pmoA and mxa) was faster under CG; RG and CG improved the ammonia-oxidizing (amoA2), nitrification (hao), and denitrification (nirS3 and nirK1) processes. The majority of the genes involved in C, N, and P cycling decreased, the C, N and P content in plant leaf decreased, while that of soil increased from early to late grazing period. No matter grazing or not, there were negative relationships between genes and soil nutrients, and positive relationships between genes and plant nutrients, implying a trade-off between plant nutrients and soil nutrients along the grazing time. The genes responsible for regulating C and N cycling were increased under grazing, implying that reasonable grazing is beneficial to the nutrients cycling of grassland. C1 [Dong, Shikui] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. [Li, Yu] Chongqing Technol & Business Univ, Sch Tourism & Land Resource, Chongqing 400067, Peoples R China. [Ganjurjav, Hasbagan; Gao, Qingzhu; Hu, Guozheng; Wu, Hongbao] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Gao, Xiaoxia; Zhang, Jing; Liu, Shiliang; Li, Shuai] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Yan, Yulong] China New Era Grp Corp, Beijing 100082, Peoples R China. [Zhang, Yong] Southwest Forestry Univ, Coll Wetlands, Natl Plateau Wetlands Res Ctr, Kunming 650224, Yunnan, Peoples R China. [Wang, Xuexia] Beijing Acad Agr & Forestry Sci, Beijing 100097, Peoples R China. RP Li, Y (通讯作者)，Chongqing Technol & Business Univ, Sch Tourism & Land Resource, Chongqing 400067, Peoples R China.; Ganjurjav, H (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM liyu4227@163.com; ganjurjav@foxmail.com TC 13 Z9 16 PD NOV 1 PY 2020 VL 303 AR 107111 DI 10.1016/j.agee.2020.107111 UT WOS:000566695800006 DA 2023-03-23 ER PT J AU Li, Z Siemann, E Deng, BL Wang, SL Gao, Y Liu, XJ Zhang, XL Guo, XM Zhang, L AF Li, Zhi Siemann, Evan Deng, Bangliang Wang, Shuli Gao, Yu Liu, Xiaojun Zhang, Xueling Guo, Xiaomin Zhang, Ling TI Soil microbial community responses to soil chemistry modifications in alpine meadows following human trampling SO CATENA DT Article AB Alpine meadow degradation induced by human trampling decreases plant biomass and species diversity, potentially altering soil chemistry and microbial community composition. We studied soil carbon (C), nitrogen (N) and phosphorus (P) plus soil bacterial and fungal community structure in alpine meadows, along a degradation gradient induced by human trampling at Wugong Mountain, China. As degradation increased (from 0 to 100% bare ground), pathotroph (both animal and plant hosts) and symbiotroph (especially ectomycorrhizae) fungal diversity increased but overall microbial diversity did not vary. Degradation altered fungal taxonomic composition with higher Cryptomycota and Mucoromycota diversity in more degraded sites. Path analyses indicated that fungal composition changes with degradation were mainly related to changes in soil C and P while bacterial changes were mainly related to changes in soil N and pH. Degradation modified bacterial taxonomic composition with higher Gemmatimonadetes but lower Acidobacteria, Cyanobacteria, and Planctomycetes diversity associated with lower pH, higher TN, lower NH4+, and higher NO3- in more degraded areas. The results indicate that trampling impacts both soil fungal and bacterial communities but these microbial groups respond to different soil chemistry modifications. These results highlighting soil microbial community changes suggest their importance in the restoration of degraded alpine meadows with human trampling and hence the rapid recovery of their function. C1 [Li, Zhi; Deng, Bangliang; Wang, Shuli; Gao, Yu; Liu, Xiaojun; Zhang, Xueling; Guo, Xiaomin; Zhang, Ling] Jiangxi Agr Univ, Coll Forestry, Jiangxi Key Lab Silviculture, Nanchang 330045, Jiangxi, Peoples R China. [Li, Zhi] Henan Agr Univ, Coll Forestry, Zhengzhou 450002, Henan, Peoples R China. [Siemann, Evan] Rice Univ, Dept Biosci, Houston, TX 77005 USA. RP Zhang, L (通讯作者)，Jiangxi Agr Univ, Coll Forestry, Jiangxi Key Lab Silviculture, Nanchang 330045, Jiangxi, Peoples R China. EM lingzhang09@126.com TC 13 Z9 13 PD NOV PY 2020 VL 194 AR 104717 DI 10.1016/j.catena.2020.104717 UT WOS:000566699000051 DA 2023-03-23 ER PT J AU Ma, WW Li, G Wu, JH Xu, GR Wu, JQ AF Ma, Weiwei Li, Guang Wu, Jianghua Xu, Guorong Wu, Jiangqi TI Response of soil labile organic carbon fractions and carbon-cycle enzyme activities to vegetation degradation in a wet meadow on the Qinghai-Tibet Plateau SO GEODERMA DT Article AB Vegetation degradation resulting from climate change and human activities in wet meadows is an important issue worldwide. This phenomenon is known to influence soil labile organic carbon (LOC) and enzyme activities due to changes in environmental conditions. However, little is known about the response of LOC and enzyme activities to vegetation degradation in high-altitude wet meadows. In this study, we examined the response of LOC and carbon-cycle enzyme activities to different intensities of vegetation degradation (i.e., non-degraded (ND), slightly degraded (SD) moderately degraded (MD), and heavily degraded (HD)) in a Tibetan wet meadow. The contents of soil organic carbon (SOC), dissolved organic carbon (DOC), microbial biomass carbon (MBC) and light fraction organic carbon (LFOC) and the carbon-cycle enzyme activities (i.e., cellulase, amylase and beta-glucosidase) were investigated in two growing seasons (2016 and 2017). We found that the content of soil SOC and LOC fractions declined with increasing soil depth in each degraded level except for HD. Vegetation degradation significantly decreased the amount of SOC at depths of 0-10 cm and 10-20 cm, and this decrease was attributed to the relative reduction of carbon source input and higher carbon decomposition. Vegetation degradation also significantly reduced the contents of SWC, DOC, MBC, LFOC, amylase and beta-glucosidase in the topsoil layers (0-10 and 10-20 cm). However, the corresponding contents in deeper soil layers had no significant differences. In addition, the SWC, DOC, LFOC and the carbon-cycle enzyme activities were higher in 2016 than in 2017. Significant correlations were obtained between SWC, SOC, LOC fractions and enzyme activities. Soil moisture was found to be the main abiotic driver for variation of soil carbon and enzyme activities. Our results indicate that vegetation degradation in the Tibetan wet meadows decreased the quantity of topsoil labile carbon fractions and enzyme activities and heavily degraded vegetation may lead to a change of profile distribution in soil carbon pool. C1 [Ma, Weiwei; Li, Guang; Xu, Guorong; Wu, Jiangqi] Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China. [Wu, Jianghua] Mem Univ Newfoundland, Sch Sci & Environm, Environm & Sustainabil, Corner Brook, NF A2H 5G4, Canada. RP Li, G (通讯作者)，Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China.; Wu, JH (通讯作者)，Mem Univ Newfoundland, Sch Sci & Environm, Environm & Sustainabil, Corner Brook, NF A2H 5G4, Canada. EM maww@gsau.edu.cn; 281205236@qq.com; jwu@grenfell.mun.ca; 1287791525@qq.com; 1462528657@qq.com TC 28 Z9 30 PD NOV 1 PY 2020 VL 377 AR 114565 DI 10.1016/j.geoderma.2020.114565 UT WOS:000560363900016 DA 2023-03-23 ER PT J AU Ma, XP Asano, M Tamura, K Zhao, RN Nakatsuka, H Wuyunna Wang, T AF Ma, Xuping Asano, Maki Tamura, Kenji Zhao, Ruonan Nakatsuka, Hiroko Wuyunna Wang, Tao TI Physicochemical properties and micromorphology of degraded alpine meadow soils in the Eastern Qinghai-Tibet Plateau SO CATENA DT Article AB The Qinghai-Tibet Plateau is currently suffering from severe ecological problems. Soil degradation is a major environmental problem, and there is strong evidence that such processes present an immediate threat to both biomass and economic yields. The aim of the present study is to clarify the response mechanism of mattic epipedon during soil degradation process in alpine meadow, we investigated (1) morphological characteristics and physicochemical properties of soils, (2) soil micromorphology under different degradation stage. According to plant and land use coverage, three sites were chosen from the Hequ horse farm: lightly degraded meadow (HQ1-L); moderately degraded meadow (HQ2-M); and heavily degraded meadow (HQ3-H). A vegetation survey and soil profile morphology showed that Kobresia kansuensis was the dominant species in HQ1-L and HQ2-M, featuring in topsoil horizons rich in rhizogenic organic matter which creates turfs. There are strong relationships between the presence of the mattic epipedon (OA horizon) and soil physicochemical properties. Thus, exchangeable cations, cation exchangeable capacity (CEC), total nitrogen (TN), and organic carbon (OC) decrease during the degradation of grassland; however, the pH value shows an opposite trend. Exchangeable cations, CEC, TN, and OC provide an index of soil fertility to measure the degree of grassland degeneration. Soils were classified as Luvic Phaeozems, Haplic Phaeozems, and Calcaric Phaeozems. From the micromorphology of soils in thin section, considering soil degradation, the porosity and fractal dimension decrease, and the soil microstructure evolves to an intergrain micro-aggregate structure. Also, by counting the number of excrements in the soil thin sections, and combining this with the fractal dimension of the porosity, we found the HQ1-L is more conducive to soil fauna survival, by comparison to HQ2-M, and HQ3-H which follow HQ1-L in condicivity. These results suggest that the existence of the OA horizon (mattic epipedon) is directly related to soil degradation. C1 [Ma, Xuping; Asano, Maki; Tamura, Kenji; Zhao, Ruonan] Univ Tsukuba, Fac Life & Environm Sci, 1-1-1 Tennodai, Tsukuba, Ibaraki 3058572, Japan. [Nakatsuka, Hiroko] Tokyo Univ Agr, Dept Agr, Tokyo, Kanagawa, Japan. [Wuyunna] Dalian Minzu Univ, Coll Environm & Resources, Dalian 116600, Liaoning, Peoples R China. [Wang, Tao] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. RP Ma, XP (通讯作者)，Univ Tsukuba, Fac Life & Environm Sci, 1-1-1 Tennodai, Tsukuba, Ibaraki 3058572, Japan. EM daojijianzan@yahoo.co.jp TC 19 Z9 20 PD NOV PY 2020 VL 194 AR 104649 DI 10.1016/j.catena.2020.104649 UT WOS:000566699000005 DA 2023-03-23 ER PT J AU Liu, X Wang, ZQ Zheng, K Han, CL Li, LH Sheng, HY Ma, ZW AF Liu, Xiang Wang, Zhaoqi Zheng, Kai Han, Chenglong Li, Lanhai Sheng, Haiyan Ma, Zhiwen TI Changes in soil carbon and nitrogen stocks following degradation of alpine grasslands on the Qinghai-Tibetan Plateau: A meta-analysis SO LAND DEGRADATION & DEVELOPMENT DT Article AB Until now, nearly 90% of alpine grasslands on the Qinghai-Tibetan Plateau (QTP) have been degraded. However, there is currently no consensus on how soil organic carbon (SOC) and soil total nitrogen (STN) stocks vary with the degradation succession of alpine grasslands in this region. Here, a meta-analysis was conducted to quantify the dynamics of SOC and STN stocks in topsoil (0-30 cm) at different degradation stages of alpine grasslands on the QTP. The results showed that grassland degradation led to average losses of 48 and 39% for SOC and STN stocks, respectively. The changes in SOC and STN stocks following grassland degradation did not differ significantly between grassland types, but were significantly affected by grassland degradation stage. The reductions in both SOC and STN stocks increased with the degradation stage, and the highest reductions were all found at extreme degradation stage. The results indicated that the depletion of SOC and STN pools were aggravated with the degradation succession of grassland. The tightly coupled SOC and STN implied that the depletion of SOC stock was closely related to that of STN stock during the process of grassland degradation. Positive relationships were detected between the dynamics of vegetation coverage and that of SOC or STN stock, indicating that vegetation coverage could not only reflect grassland degradation, but might also be a potential indicator of SOC and STN status. The findings suggest that preventing the degradation succession of alpine grasslands is vital to maintain or promote SOC and STN levels on the QTP. C1 [Liu, Xiang; Wang, Zhaoqi; Zheng, Kai; Han, Chenglong; Sheng, Haiyan; Ma, Zhiwen] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China. [Li, Lanhai] Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China. [Li, Lanhai] Chinese Acad Sci, Ili Stn Watershed Ecosyst Res, Xinyuan, Peoples R China. [Li, Lanhai] Univ Chinese Acad Sci, Beijing, Peoples R China. [Li, Lanhai] Xinjiang Key Lab Water Cycle & Utilizat Arid Zone, Urumqi 830011, Peoples R China. [Li, Lanhai; Ma, Zhiwen] Qinghai Univ, Coll Agr & Anim Husb, Xining, Peoples R China. [Li, Lanhai; Ma, Zhiwen] Qinghai Univ, Coll Ecoenvironm Engn, Xining, Peoples R China. RP Ma, ZW (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Peoples R China.; Li, LH (通讯作者)，Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China. EM lilh@ms.xjb.ac.cn; mazhiwen14@mails.ucas.ac.cn TC 18 Z9 19 PD FEB 15 PY 2021 VL 32 IS 3 BP 1262 EP 1273 DI 10.1002/ldr.3796 EA OCT 2020 UT WOS:000585931400001 DA 2023-03-23 ER PT J AU Zhang, ZC Sun, J AF Zhang, Zhenchao Sun, Jian TI Root Features Determine the Increasing Proportion of Forbs in Response to Degradation in Alpine Steppe, Tibetan Plateau SO FRONTIERS IN ENVIRONMENTAL SCIENCE DT Article AB Understanding the response of plant community to degradation is fundamentally important for grassland conservation and management. The objective of this study is to examine the changes in soil properties and plant characteristics along a degradation gradient in alpine steppe, and explore the potential mechanisms that biotic and abiotic controls regulate plant community variations. We chose seven sequent degrees of degradation, and conducted a field survey as well as soil and plant samplings in an alpine steppe in Northern Tibet. The results showed that soil water content (SWC), soil compaction (SCOM), soil total carbon (STC), and total nitrogen (STN) dramatically decreased along the degradation gradient. The species richness, overall aboveground biomass (AGB), and AGB of graminoids were apparently reduced with increasing degradation, while AGB of forbs slightly increased. The increasing degradation levels induced a significant increase in the trade-off value of AGB of forbs, which was negatively associated with SWC, SCOM, STC, STN, and soil available nitrogen. The mean root length of forbs was significantly longer than that of graminoids (P < 0.05). Moreover, the mean root diameter of the top 1/3 part of forbs was remarkably thicker than that of graminoids (P < 0.05). These findings indicate that the degradation-induced cohesionless soils with insufficient water and nutrients together with the divergent root morphological traits of graminoids and forbs determine the plant community structure shift with grassland degradation. This study can improve the understanding of community succession of grassland degradation, and provide guidance for the management of degraded alpine steppe on the Tibetan Plateau. C1 [Zhang, Zhenchao; Sun, Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, Beijing, Peoples R China. [Zhang, Zhenchao] Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing, Peoples R China. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, Beijing, Peoples R China. EM sunjian@igsnrr.ac.cn TC 6 Z9 6 PD OCT 26 PY 2020 VL 8 AR 534774 DI 10.3389/fenvs.2020.534774 UT WOS:000587388800001 DA 2023-03-23 ER PT J AU Zhou, WC Cui, LJ Wang, YF Li, W Kang, XM AF Zhou, Wenchang Cui, Lijuan Wang, Yifei Li, Wei Kang, Xiaoming TI Carbon emission flux and storage in the degraded peatlands of the Zoige alpine area in the Qinghai-Tibetan Plateau SO SOIL USE AND MANAGEMENT DT Article AB The Zoige alpine peatlands cover approximately 4,605 km(2) of the Qinghai-Tibetan Plateau and are considered to constitute the largest plateau peatland on the Eurasian continent. However, the Zoige alpine peatlands are undergoing major degradation because of human activities and climate change, which would cause uncertainty in the budget of greenhouse gases (CH4 and CO2) and carbon (C) storage in global peatlands. This study simultaneously investigates the CH4 and CO2 emission fluxes and C storage at three typical sites with respect to the peatland degradation gradient: peatland, wet meadow and dry meadow. Results show that peatland degradation would increase the CO2 emission and decrease the CH4 emission. Moreover, the average C emission fluxes were 66.05, 165.78 and 326.56 mg C m(-2) hr(-1) for the peatland, wet meadow and dry meadow, respectively. The C storage of the vegetation does not considerably differ among the three sampling sites. However, when compared with the peatland (1,088.17 t C ha(-1)), the soil organic C storage decreases by 420 and 570 t C ha(-1) in case of wet and dry meadows, respectively. Although the C storage in the degraded peatlands decreases considerably, it can still represent a large capacity of C sink. Therefore, the degraded peatlands in the Zoige alpine area must be protected and restored to mitigate regional climate change. C1 [Zhou, Wenchang; Cui, Lijuan; Wang, Yifei; Li, Wei; Kang, Xiaoming] Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China. [Zhou, Wenchang; Cui, Lijuan; Wang, Yifei; Li, Wei; Kang, Xiaoming] Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China. [Zhou, Wenchang] Hubei Acad Forestry, East Lake Hightech Dev Zone, Wuhan, Peoples R China. [Wang, Yifei; Kang, Xiaoming] Sichuan Zoige Wetland Ecosyst Res Stn, Tibetan Autonomous Prefecture Aba, Aba, Peoples R China. RP Zhou, WC; Cui, LJ (通讯作者)，Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China.; Zhou, WC; Cui, LJ (通讯作者)，Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China.; Zhou, WC (通讯作者)，Hubei Acad Forestry, East Lake Hightech Dev Zone, Wuhan, Peoples R China. EM zwclky@126.com; lkyclj@126.com TC 4 Z9 6 PD JAN PY 2021 VL 37 IS 1 BP 72 EP 82 DI 10.1111/sum.12660 EA OCT 2020 UT WOS:000583368100001 DA 2023-03-23 ER PT J AU Liu, YJ Zhang, YJ Huang, K Zu, JX Chen, N Cong, N AF Liu, Yaojie Zhang, Yangjian Huang, Ke Zu, Jiaxing Chen, Ning Cong, Nan TI Increased Surface Broadband Emissivity Driven by Denser Vegetation on the Tibetan Plateau Grassland Area SO JOURNAL OF THE INDIAN SOCIETY OF REMOTE SENSING DT Article AB Global changes are profoundly affecting the global terrestrial ecosystems, especially for the vegetation. Simultaneously, the affected vegetation gives feedback to the climates. The Tibetan Plateau (TP), one of the most sensitive areas to global changes, has undergone extraordinary changes on its ecosystem processes. In the multitudinous land surface ecosystem processes affecting the climate, the process of land surface energy balance affecting by vegetation activity is one of the most important and still has not been well recognized. The spatial and temporal patterns of the broadband emissivity (BBE) on the TP and its relations to the vegetation activity and land surface temperature were examined in this research. We find that elevated BBE is regulated by increasing vegetation activity for grasslands over the TP from 2000 to 2015. The spatial patterns of BBE and its interannual changes are highly correlated with vegetation activity. The BBE changing rate generally declines along rising elevation, due to the shrunk effects from vegetation activity. A greater sensitivity of BBE to vegetation activity occurs in the sparse vegetation area or high elevation zone than in the dense vegetation area or low elevation zone. Increasing BBE has a cooling effect on the land surface, especially at night. This cooling effect is related to wind speed. The growing season BBE trend as regulated by vegetation activity highlights the importance to take mounting notice of the growing season long-wave energy fluxes of surface energy balance studies in the future. C1 [Liu, Yaojie; Zhang, Yangjian; Huang, Ke; Zu, Jiaxing; Chen, Ning; Cong, Nan] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. [Liu, Yaojie; Zhang, Yangjian; Zu, Jiaxing; Chen, Ning] Chinese Acad Sci, Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100090, Peoples R China. [Liu, Yaojie] Nanjing Univ, Int Inst Earth Syst Sci, Nanjing 210023, Peoples R China. [Liu, Yaojie] Nanjing Univ, Sch Geog & Ocean Sci, Nanjing 210023, Peoples R China. [Zhang, Yangjian] Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. RP Cong, N (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. EM liuyj.l4b@igsnrr.ac.cn; zhangyj@igsnrr.ac.cn; huangk.13b@igsnrr.ac.cn; zujx.15b@igsnrr.ac.cn; chenn.16b@igsnrr.ac.cn; congnan@igsnrr.ac.cn TC 1 Z9 1 PD DEC PY 2020 VL 48 IS 12 BP 1845 EP 1859 DI 10.1007/s12524-020-01195-4 EA OCT 2020 UT WOS:000578415000002 DA 2023-03-23 ER PT J AU Xiao, YM Li, CB Yang, Y Peng, YF Yang, YH Zhou, GY AF Xiao, Yuanming Li, Changbin Yang, Yang Peng, Yunfeng Yang, Yuanhe Zhou, Guoying TI Soil Fungal Community Composition, Not Assembly Process, Was Altered by Nitrogen Addition and Precipitation Changes at an Alpine Steppe SO FRONTIERS IN MICROBIOLOGY DT Article AB Global climate change and nitrogen deposition have been having broad impacts on microorganisms. On the Qinghai-Tibetan Plateau (QTP), the responses of soil microbial community assemblage and diversity to nitrogen deposition and changes in precipitation are poorly understood, especially in the alpine steppe. In this study, we conducted a field manipulative experiment of nitrogen deposition and precipitation amount in an alpine steppe on the northeastern QTP and investigated the responses of community composition, diversity, and community assemblage of soil fungi. Soil fungal community compositions were significantly altered under nitrogen addition, precipitation change, and their interaction, and positively related with soil moisture, soil pH, and plant species richness. However, they were negatively related to soil mineralizable N and soil available P content. Operational taxonomic units (OTU) richness and Chao 1 index decreased under nitrogen addition combined with precipitation reduction treatment, whereas the Shannon-Wiener index declined only under precipitation increment treatment. Convergent fungal community assembly processes were not acutely altered by both nitrogen addition and precipitation changes, indicating that environmental filtering was a dominant ecological process controlling fungal community assemblage. By elucidating the above questions, the study enhanced our ability to predict the responses of soil fungal communities to nitrogen deposition and precipitation changes at alpine steppes on the QTP in the future. C1 [Xiao, Yuanming; Li, Changbin; Yang, Yang; Zhou, Guoying] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Peoples R China. [Xiao, Yuanming; Li, Changbin; Yang, Yang] Univ Chinese Acad Sci, Coll Life Sci, Beijing, Peoples R China. [Peng, Yunfeng; Yang, Yuanhe] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. [Zhou, Guoying] Chinese Acad Sci, Key Lab Tibetan Med Res, Xining, Peoples R China. [Zhou, Guoying] Qinghai Key Lab Qinghai Tibetan Plateau Biol Reso, Xining, Peoples R China. RP Zhou, GY (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Peoples R China.; Zhou, GY (通讯作者)，Chinese Acad Sci, Key Lab Tibetan Med Res, Xining, Peoples R China.; Zhou, GY (通讯作者)，Qinghai Key Lab Qinghai Tibetan Plateau Biol Reso, Xining, Peoples R China. EM zhougy@nwipb.cas.cn TC 5 Z9 5 PD OCT 16 PY 2020 VL 11 AR 579072 DI 10.3389/fmicb.2020.579072 UT WOS:000584782400001 DA 2023-03-23 ER PT J AU Lin, ZJ Gao, ZY Fan, XW Niu, FJ Luo, J Yin, GA Liu, MH AF Lin, Zhanju Gao, Zeyong Fan, Xingwen Niu, Fujun Luo, Jing Yin, Guoan Liu, Minghao TI Factors controlling near surface ground-ice characteristics in a region of warm permafrost, Beiluhe Basin, Qinghai-Tibet Plateau SO GEODERMA DT Article AB Ground ice is a key component of permafrost, and its melt induced by climate change and anthropogenic disturbance has been causing increased ground surface subsidence, thermal erosion, and engineering problems. However, the distribution and quantity of ground ice in permafrost have yet to be investigated in detail on the Qinghai-Tibet Plateau (QTP), and consequently, an assessment of the nature of impacts associated with permafrost degradation is challenging. In this study, variation in near-surface ground ice content of the upper 2-3 m of the permafrost layer was examined by drilling 72 boreholes at eight sites in Beiluhe Basin, QTP, an area with relatively warm (near 0 degrees C) permafrost. High ground ice contents occur at most sites, but visible ice was absent at one site, where the vegetation cover has transitioned from a meadow to a sparsely-covered grassland. The moisture content within the active layer (surface to 2 m depth) increases with depth at most sites, and the higher moisture contents were associated with greater near-surface ground ice contents. The gravimetric moisture content (M-g) in permafrost typically ranged from 8% to 500%, and similar to 76% of samples were classified as ice rich (M-g >= 20%). The mean excess-ice content in near-surface permafrost was similar to 19% for all boreholes. At six flat sites, the minimum mean excess-ice content was about zero, and the mean maximum was similar to 22% at an alpine grassland site. The mean excess-ice content at a sunny sloping site was much higher (similar to 27%) than at a north-facing shady site (10%) and the ice was distributed differently with depth. The mean subsidence ratio at the eight sites was from 0.05 to 0.44. The volumetric ice content varied from 1% to 70% in samples from the different sites, with an average value of similar to 16%. Topographically controlled moisture availability, slope direction, and fine-particle content are important controls on ground ice content in Beiluhe Basin. This study provides fundamental information about the spatial distribution of ground ice on QTP, which is important for future assessments of thermal erosion potential and infrastructure instability in the region. C1 [Lin, Zhanju; Gao, Zeyong; Fan, Xingwen; Niu, Fujun; Luo, Jing; Yin, Guoan; Liu, Minghao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. RP Lin, ZJ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. EM zhanjulin@lzb.ac.cn TC 17 Z9 19 PD OCT 15 PY 2020 VL 376 AR 114540 DI 10.1016/j.geoderma.2020.114540 UT WOS:000558138300008 DA 2023-03-23 ER PT J AU Bai, YF Ma, LN Degen, AA Rafiq, MK Kuzyakov, Y Zhao, JX Zhang, R Zhang, T Wang, WY Li, XG Long, RJ Shang, ZH AF Bai, Yanfu Ma, Lina Degen, Abraham A. Rafiq, Muhammad K. Kuzyakov, Yakov Zhao, Jingxue Zhang, Rui Zhang, Tao Wang, Wenyin Li, Xiaogang Long, Ruijun Shang, Zhanhuan TI Long-term active restoration of extremely degraded alpine grassland accelerated turnover and increased stability of soil carbon SO GLOBAL CHANGE BIOLOGY DT Article AB Soil nutrient contents and organic carbon (C) stability are key indicators for restoration of degraded grassland. However, the effects of long-term active restoration of extremely degraded grassland on soil parameters have been equivocal. The aims of this study were to evaluate the impact of active restoration of degraded alpine grassland on: (a) soil organic matter (SOM) mineralization; and (b) the importance of biotic factors for temperature sensitivity (Q(10)) of SOM mineralization. Soils were sampled from intact, degraded and restored alpine grasslands at altitudes ranging between 3,900 and 4,200 m on the Tibetan Plateau. The samples were incubated at 5, 15 and 25 degrees C, andQ(10)values of SOM mineralization were determined. Structural equation modeling was used to evaluate the importance of vegetation, soil physico-chemical properties and microbial parameters forQ(10)regulation. TheQ(10)of N mineralization was similar among intact, degraded and restored soils (0.84-1.24) and was higher in topsoil (1.09) than in subsoil (0.92). The best predictive factor of CO2-Q(10)for intact grassland was microbial biomass, for degraded grassland was basal microbial respiration, and for restored grassland was soil bulk density. Restoration by planting vegetation decreased theQ(10)of SOM mineralization as soil bulk density, the most important negative predictor, increased in restored grassland. TheQ(10)of SOM mineralization in topsoil was 14% higher than in subsoil because of higher microbial abundance and exo-enzyme activities. The NH(4)(+)content was greatest in intact soil, while NO(3)(-)content was greatest in degraded soil. The SOM mineralization rate decreased with grassland degradation and increased after long-term (>10 years) restoration. In conclusion, extremely degraded grassland needs proper long-term management in active restoration projects, especially for improvement of soil nutrients in a harsh environment. C1 [Bai, Yanfu; Ma, Lina; Zhang, Tao; Wang, Wenyin; Li, Xiaogang; Long, Ruijun; Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Degen, Abraham A.] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, Beer Sheva, Israel. [Rafiq, Muhammad K.] Natl Agr Res Ctr, Rangeland Res Inst, Islamabad, Pakistan. [Rafiq, Muhammad K.] Univ Edinburgh, Sch Geosci, UK Biochar Res Ctr, Edinburgh, Midlothian, Scotland. [Kuzyakov, Yakov] Univ Gottingen, Dept Agr Soil Sci, Dept Soil Sci Temperate Ecosyst, Gottingen, Germany. [Kuzyakov, Yakov] RUDN Univ, Agrotechnol Inst, Moscow, Russia. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan, Russia. [Zhao, Jingxue] Lanzhou Univ, Inst Innovat Ecol, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. [Zhao, Jingxue] Lanzhou Univ, Coll Life Sci, Lanzhou, Peoples R China. [Zhang, Rui] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Urat Desert Grassland Res Stn, Lanzhou, Peoples R China. [Shang, Zhanhuan] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Area, Xining, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. EM shangzhh@lzu.edu.cn TC 16 Z9 21 PD DEC PY 2020 VL 26 IS 12 BP 7217 EP 7228 DI 10.1111/gcb.15361 EA OCT 2020 UT WOS:000578729900001 DA 2023-03-23 ER PT J AU Lin, HL Zhang, F AF Lin, Huilong Zhang, Feng TI Fragmentation and percolation thresholds in the degradation process of alpine meadow in the Three-River Headwaters region of Qinghai-Tibetan Plateau, China SO RANGELAND JOURNAL DT Article AB Understanding the process and mechanisms of alpine meadow degradation is crucial for restoration and management in the Three-River Headwaters region, Qinghai-Tibetan Plateau, China. However, little is known about this complex and controversial problem because identification and quantification of the underlying causes is difficult. This research aimed to build a spatiotemporal dynamical model for alpine meadow degradation, capturing the natural process of erosion at the interface of barren patches and undamaged meadow. The model clarified the role of barren patches and meadow connectivity in degradation, and identified the ecological mechanisms and processes accounting for the spatial and temporal pattern of degradation. A fragmentation and percolation threshold exists in the process of meadow degradation, independent of spatial scale. An impulsive differential equation was used to investigate the consequence of periodic restoration of degraded meadow. Both the level of meadow degradation and the restoration period play crucial roles in determining whether the meadow can be successfully restored. This research has demonstrated theoretically that the effectiveness of meadow restoration by periodic effort depends on the degree of degradation. C1 [Lin, Huilong] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China. [Lin, Huilong] Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Gansu, Peoples R China. [Lin, Huilong] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Gansu, Peoples R China. [Zhang, Feng] Anhui Univ, Anhui Prov Key Lab Wetland Ecosyst Protect & Rest, Sch Resources & Environm Engn, Hefei 230601, Anhui, Peoples R China. RP Zhang, F (通讯作者)，Anhui Univ, Anhui Prov Key Lab Wetland Ecosyst Protect & Rest, Sch Resources & Environm Engn, Hefei 230601, Anhui, Peoples R China. EM fzhang188@163.com TC 2 Z9 3 PY 2020 VL 42 IS 3 BP 171 EP 177 DI 10.1071/RJ20005 EA OCT 2020 UT WOS:000576236600001 DA 2023-03-23 ER PT J AU Chen, JH Yan, F Lu, Q AF Chen, Junhan Yan, Feng Lu, Qi TI Spatiotemporal Variation of Vegetation on the Qinghai-Tibet Plateau and the Influence of Climatic Factors and Human Activities on Vegetation Trend (2000-2019) SO REMOTE SENSING DT Article AB Vegetation is the terrestrial ecosystem component most sensitive to climate change. The Qinghai-Tibet Plateau (QTP), characterized by a cold climate and vulnerable ecosystems, has experienced significant warming in previous decades. Identifying the variation in vegetation coverage and elucidating its main driving factors are critical for ecological protection on the QTP. In this study, MOD13A2 Normalized Difference Vegetation Index (NDVI) data in the growing season (May to September) was used to represent QTP vegetation coverage during 2000-2019. The univariate linear regression, partial correlation analysis, residual analysis, and the Hurst exponent were used to detect the vegetation spatiotemporal dynamic, analyze the relationship between the vegetation and main driving factors, and predict the future vegetation dynamic. The growing season NDVI (GNDVI) of the QTP showed an extremely significant rate of increase (0.0011/a) during the study period, and 79.29% of the vegetated areas showed a greening trend. Over the past 20 years, the northeast, mid-east, and western edges of the plateau have been cooling and wetting, while the southwest, mid-west, and southeast have been warming and drying. Different climatic conditions lead to spatial differences in the response of plateau vegetation to climatic factors with generally 1-4 months lag time. The vegetation in the north of the plateau was mainly positively correlated with moisture, and negatively correlated with temperature, while the southern part showed positive correlation with temperature and negative correlation with moisture. Due to the enhancement of cooling and wetting trend in the last decade (2010-2019), especially in the south of the plateau, the greening trend of the plateau vegetation slowed down appreciably and even degraded in some areas. Human activities were mainly concentrated in the eastern part of the plateau-and its positive effect on vegetation was gradually increasing in most areas during study period, especially in the northeastern part. However, vegetation degradation caused by human activities in the southeast of the plateau should not be ignored. The future vegetation dynamic based on the Hurst exponent showed that the plateau faces a higher risk of vegetation degradation, which deserves more attention. This study explored the effect of climatic factors and human activities on vegetation of the QTP, thereby providing some guidance for the study of vegetation dynamic in the alpine areas. C1 [Chen, Junhan; Yan, Feng; Lu, Qi] Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. RP Yan, F (通讯作者)，Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. EM chenjunhan@caf.ac.cn; fyan@caf.ac.cn; luqi@caf.ac.cn TC 49 Z9 54 PD OCT PY 2020 VL 12 IS 19 AR 3150 DI 10.3390/rs12193150 UT WOS:000586577000001 DA 2023-03-23 ER PT J AU Gu, J Pang, QT Ding, JZ Yin, RS Yang, YH Zhang, YX AF Gu, Jing Pang, Qiaotong Ding, Jinzhi Yin, Runsheng Yang, Yuanhe Zhang, Yanxu TI The driving factors of mercury storage in the Tibetan grassland soils underlain by permafrost SO ENVIRONMENTAL POLLUTION DT Article AB Soils, especially permafrost in the Arctic and the Tibetan Plateau, are one of the largest reservoirs of mercury (Hg) in the global environment. The Hg concentration in the grassland soils over the Tibetan Plateau and its driving factors have been less studied. This study analyzes soil total mercury (STHg) concentrations and its vertical distribution in grassland soil samples collected from the Tibetan Plateau. We adopt a nested-grid high-resolution GEOS-Chem model to simulate atmospheric Hg deposition. The relationship between STHg and soil organic carbon (SOC), as well as atmospheric deposition, are explored. Our results show that the STHg concentrations in the Tibetan Plateau are 19.8 +/- 12.2 ng/g. The concentrations are higher in the south and lower in the north in the Tibetan Plateau, consistent with the previous results. Our model shows that the average deposition flux of Hg is 3.3 mu g m(-2) yr(-1), with 57% contributed by dry deposition of elemental mercury (Hg-0), followed by dry (19%) and wet (24%) deposition of divalent mercury. We calculate the Hg to carbon ratio (R-Hg:C) as 5.6 +/- 6.5 mu g Hg/g C, and the estimated STHg is 86.6 +/- 101.2 Gg in alpine grasslands in the Tibetan Plateau. We find a positive relationship between STHg and SOC in the Tibetan Plateau (r(2) = 0.36) and a similar positive relationship between STHg and atmospheric total Hg deposition (r(2) = 0.24). A multiple linear regression involving both variables better model the observed STHg (r(2) = 0.42). We conclude that SOC and atmospheric deposition influence STHg simultaneously in this region. The data provides information to quantify the size of the soil Hg pool in the Tibetan Plateau further, which has important implications for the Hg cycles in the permafrost regions as well as on the global scale. (C) 2020 Elsevier Ltd. All rights reserved. C1 [Gu, Jing; Pang, Qiaotong; Zhang, Yanxu] Nanjing Univ, Sch Atmospher Sci, Nanjing 210023, Peoples R China. [Ding, Jinzhi] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100085, Peoples R China. [Yin, Runsheng] Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang 550081, Peoples R China. [Yang, Yuanhe] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. RP Zhang, YX (通讯作者)，Nanjing Univ, Sch Atmospher Sci, Nanjing 210023, Peoples R China. EM zhangyx@nju.edu.cn TC 4 Z9 6 PD OCT PY 2020 VL 265 AR 115079 DI 10.1016/j.envpol.2020.115079 PN B UT WOS:000564561100005 DA 2023-03-23 ER PT J AU Wang, DJ Zhou, HK Yao, BQ Wang, WY Dong, SK Shang, ZH She, YD Ma, L Huang, XT Zhang, ZH Zhang, Q Zhao, FY Zuo, J Mao, Z AF Wang, Dangjun Zhou, Huakun Yao, Buqing Wang, Wenying Dong, Shikui Shang, Zhanhuan She, Yandi Ma, Li Huang, Xiaotao Zhang, Zhonghua Zhang, Qian Zhao, Fengyu Zuo, Juan Mao, Zhun TI Effects of nutrient addition on degraded alpine grasslands of the Qinghai-Tibetan Plateau: A meta-analysis SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Climate warming and human disturbance are supposed to have severely affected the alpine grasslands on the Qinghai-Tibetan Plateau (QTP), a region where the extremely harsh and fragile ecological environment has attracted great attention because of its sensitivity to global change. However, there is still no unified understanding of the degree and magnitude of grassland degradation and the effectiveness of nutrient addition in this vast landscape, since most previous studies have focused on short-term observations at a single site. Here, we conducted a meta-analysis of 145 published studies on degraded alpine grassland along with 90 published studies, which concerning nutrient addition (nitrogen [N], phosphorus [P], and combined N and P [NP]) to quantitatively assess the responses of plant and soil characteristics to land degradation and restoration. Our results revealed that the response ratio (RR) of above-ground biomass (AGB), below-ground biomass (BGB), soil organic carbon (SOC), and soil total N (TN) decreased significantly (- 47.23 %, -43.45 %, -32.35 %, and - 37.97 %, respectively) in degraded grassland compared with non-degraded grassland. The RR of AGB was correlated with mean annual precipitation (MAP), while the RR of BGB was correlated with the interaction of MAP and mean annual temperature (MAT). Severely degraded grassland required additional nutrients to aid recovery. NP addition to severely degraded sites increased plant AGB (+32.44 %), TN (+ 10.99 %), soil total P (+ 32.25 %), and soil moisture (+ 9.21 %), but significantly decreased species richness (-45.46 %), diversity (- 30.40 % for Shannon- Wiener index) and soil pH (- 3.91 %). N addition increased the RR of AGB and grass biomass significantly by 28.77 % and 36.49 %, but had no significant effect on sedge and forb biomass. MAP influenced the RR of AGB, TN, TP under NP addition, the RR of BGB and the AGB of different function groups were significantly affected by MAT. We evidenced that the QTP has endured severe vegetation and soil degradation, which cannot be completely mitigated by supplementary fertilisation. Fertilisation could yield positive effects on plant performance and soil quality, but negative effects on biodiversity. Climate warming and associated precipitation change may regulate the effects of fertiliser on plant biomass and soil nutrients. C1 [Wang, Dangjun; Zuo, Juan] Chinese Acad Sci, Key Lab Aquat Bot & Watershed Ecol, Wuhan Bot Garden, Wuhan 430074, Peoples R China. [Wang, Dangjun; Zhou, Huakun; Yao, Buqing; She, Yandi; Ma, Li; Huang, Xiaotao; Zhang, Zhonghua; Zhang, Qian] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, Xining 810008, Peoples R China. [Wang, Dangjun; Zuo, Juan] Chinese Acad Sci, Ctr Plant Ecol, Core Bot Gardens, Wuhan 430074, Peoples R China. [Wang, Dangjun; She, Yandi; Ma, Li; Zhang, Zhonghua; Zhang, Qian] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Wenying] Qinghai Normal Univ, Coll Life Sci, Xining 810008, Peoples R China. [Dong, Shikui] Beijing Forestry Univ, Sch Grassland Sci, Beijing 100083, Peoples R China. [Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Zhao, Fengyu] Qinghai Forestry & Grassland Bur, Xining 810000, Peoples R China. [Mao, Zhun] Univ Montpellier, INRAE, CNRS, CIRAD,IRD,AMAP, Montpellier, France. RP Zhou, HK (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Cold Reg Restorat Ecol, Xining 810008, Peoples R China. EM hkzhou@nwipb.cas.cn TC 17 Z9 19 PD OCT 1 PY 2020 VL 301 AR 106970 DI 10.1016/j.agee.2020.106970 UT WOS:000553393400001 DA 2023-03-23 ER PT J AU Wei, HC Ma, CY Zhang, J Sun, YJ Li, QK Hou, GL Duan, RL AF Wei, Haicheng Ma, Chongyi Zhang, Jing Sun, Yongjuan Li, Qingkuan Hou, Guangliang Duan, Ronglei TI Climate change and anthropogenic activities in Qinghai Lake basin over the last 8500 years derived from pollen and charcoal records in an aeolian section SO CATENA DT Article AB The Qinghai Lake basin (QLB) is an ideal region to explore the interaction between climate change, vegetation evolution, and anthropogenic activities during the Holocene epoch. This is due to the basin's particular sensitivity to global climate changes along with its densely distributed archeological sites, present since the last deglaciation. To date, a full understanding of the lakeshore terrestrial fossil pollen record is lacking and few studies have explored the human signals in the pollen spectra of the northeast Qinghai-Tibetan Plateau. Here, we present fossil pollen and charcoal records from over 8500 years ago obtained from a high resolution-dated aeolian section in the southeastern margin of the QLB. These results show that the pollen spectra are dominated by herbaceous and shrubby pollen taxa, while arboreal pollen taxa are rare. From approximately 8.5-7.2 ka, Artemisia- and Poaceae- dominated temperate steppe developed in the region, suggesting relatively warm and dry climatic conditions. Comparatively, regional vegetation shifted to Cyperaceae-dominated alpine meadow from approximately 7.2-3.4 ka, which reflected cooler and wetter climatic conditions. Thereafter, the amount of Asteraceae, Artemisia, and Chenopodiaceae notably increased from approximately 3.4-1.8 ka, suggesting that temperate steppe dominated the region under relative drier climate. Noticeably, an interval between approximately 1.8-0.6 ka was characterized by an increase of Hippophae pollen, reflecting a comparatively warmer episode; alpine meadow then reoccupied the region since approximately 0.6 ka. Combining the variations of charcoal concentrations (20-50 mu m and > 50 mu m) with human-related pollen taxa (Aster-type, Chenopodiaceae, Plantago, and Hordeum-type), we inferred that prehistoric humans were extensively using fire for hunting and subsistence during 7.2-3.5 ka, which strongly impacted the local vegetation during the middle Holocene; regional grazing activities intensified and caused grassland degradation since approximately 3.5 ka, which manifested with a significant increase in Aster-type and Chenopodiaceae pollen. After this period, Hordeum-type pollen as well as charcoal concentration of > 50 mu m increased significantly since approximately 2.2 ka, suggesting an intensifying agricultural cultivation in the region. C1 [Wei, Haicheng; Sun, Yongjuan; Li, Qingkuan] Chinese Acad Sci, Qinghai Inst Salt Lakes, Key Lab Comprehens & Highly Efficient Utilizat Sa, Xining 810008, Peoples R China. [Wei, Haicheng; Sun, Yongjuan; Li, Qingkuan] Chinese Acad Sci, Qinghai Inst Salt Lakes, Qinghai Prov Key Lab Geol & Environm Salt Lakes, Xining 810008, Peoples R China. [Wei, Haicheng] Chinese Acad Sci, Nanjing Inst Geol & Palaeontol, State Key Lab Palaeobiol & Stratig, Nanjing 210008, Peoples R China. [Ma, Chongyi; Zhang, Jing; Sun, Yongjuan; Hou, Guangliang; Duan, Ronglei] Qinghai Normal Univ, Sch Geog Sci, Qinghai Prov Key Lab Phys Geog & Environm Proc, Xining 810008, Peoples R China. RP Wei, HC (通讯作者)，Chinese Acad Sci, Qinghai Inst Salt Lakes, Key Lab Comprehens & Highly Efficient Utilizat Sa, Xining 810008, Peoples R China.; Wei, HC (通讯作者)，Chinese Acad Sci, Qinghai Inst Salt Lakes, Qinghai Prov Key Lab Geol & Environm Salt Lakes, Xining 810008, Peoples R China.; Wei, HC (通讯作者)，Chinese Acad Sci, Nanjing Inst Geol & Palaeontol, State Key Lab Palaeobiol & Stratig, Nanjing 210008, Peoples R China.; Ma, CY (通讯作者)，Qinghai Normal Univ, Sch Geog Sci, Qinghai Prov Key Lab Phys Geog & Environm Proc, Xining 810008, Peoples R China. EM hcwei@isl.ac.cn; echongyi@163.com TC 25 Z9 27 PD OCT PY 2020 VL 193 AR 104616 DI 10.1016/j.catena.2020.104616 UT WOS:000538770800013 DA 2023-03-23 ER PT J AU Wang, JL Yuan, Y Zhang, MJ Dai, XQ He, HD Li, HQ Li, YN AF Wang, Jianlei Yuan, Ye Zhang, Mingjiang Dai, Xiaoqin He, Huidan Li, Hongqin Li, Yingnian TI Impact of degradation and restoration on soil fungi and extracellular enzyme activity in alpine rangelands on the Tibetan Plateau SO ARCHIVES OF AGRONOMY AND SOIL SCIENCE DT Article AB Degradation and enclosure can change plant composition and soil properties, thereby alter soil microbial community, diversity and activity. This study used high-throughput sequencing and microplate fluorometric to determine the patterns of soil fungal community and extracellular enzyme activity (EEA) under degradation and restoration on the Tibetan Plateau. Three degradation (including: non-degraded, DN; moderately degraded, DM; and severely degraded, DS) and three enclosure (including: 5 years, EI; 10 years, EII; and 15 years, EIII) treatments were set up. DM and DS increased the species richness of fungi compared with DN. EI decreased the fungal diversity compared with DS while EII significantly increased it. DM significantly increased EEA while DS had no significant effect on any EEA compared to DN. EI decreased EEA (significant for beta X), EII increased EEA (significant for beta G) compared with DS while EIII had no significant effect. This variation of EEA among different degradation and enclosure treatments could be partially explained by soil properties and fungal community but had no relation with plant properties. The degradation could change soil fungi and extracellular enzyme activity and may adversely affect vegetation health in the alpine ecosystem. Enclosure could partially reverse these changes, but long-term field experiments are still needed. C1 [Wang, Jianlei; He, Huidan; Li, Hongqin; Li, Yingnian] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. [Wang, Jianlei; Zhang, Mingjiang] GRINM Resources & Environm Tech Co Ltd, Natl Engn Lab Biohydromet, Beijing, Peoples R China. [Yuan, Ye] Anhui Normal Univ, Coll Life Sci, Anhui Prov Key Lab Conservat & Exploitat Biol Res, Wuhu, Peoples R China. [Dai, Xiaoqin] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Qianyanzhou Ecol Res Stn, Beijing, Peoples R China. RP Yuan, Y (通讯作者)，Anhui Normal Univ, Wuhu 241002, Peoples R China. EM yuanye_1985@ahnu.edu.cn TC 1 Z9 1 PD DEC 6 PY 2021 VL 67 IS 14 BP 1917 EP 1929 DI 10.1080/03650340.2020.1818071 EA SEP 2020 UT WOS:000572205700001 DA 2023-03-23 ER PT J AU Zhang, LR Lv, WW Cui, SJ Jiang, LL Li, BW Liu, PP Wang, Q Zhou, Y Hong, H Wang, A Luo, CY Zhang, ZH Dorji, T Wang, SP AF Zhang, Lirong Lv, Wangwang Cui, Shujuan Jiang, Lili Li, Bowen Liu, Peipei Wang, Qi Zhou, Yang Hong, Huan Wang, A. Luo, Caiyun Zhang, Zhenhua Dorji, Tsechoe Wang, Shiping TI Effect of warming and degradation on phenophases of Kobresia pygmaea and Potentilla multifida on the Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Many studies have focused on the responses of phenophases to warming in natural, non-degraded grasslands. However, degraded grasslands widely distribute in the world due to climate change and overgrazing. So far, a comprehensive understanding of how plant phenology responds to warming, degradation and their interactions remains elusive. Here, the relative effects of warming and degradation on the phenological sequences of two dominant plant species were tested using a two factorial experiment of warming and moderate degradation (i.e., four treatments: NWND, WND, NWD and WD) during three successive years. We found that WND significantly delayed the onsets of early phenophases (i.e., leaf-out, booting-seL flowering and fruiting-set) and shortened the total activity period (TAP) only for the early spring flowering Kobresia pygmaea compared with NWND. NWD generally did not significantly affect the timing or duration of all phenophases for the two plant species depending on year relative to NWND. Interaction between warming and moderate degradation significantly delayed leaf-out and shortened total activity period of the two plant species. There were negative correlations between plant species richness and onset of vegetation after fruiting-set for K. pygmaea and the duration of fruiting-set for Potentilla multifida (a dominant mid-summer flowering species in degraded plots), but there were positive correlations between plant species richness and leafing duration for P. multifida. Positive correlations were found between first leaf-out and NO3--N in soils for both species but negative correlations were found between first leaf-out and NH4--N in soils for P. multifida. There were positive and negative correlations between TAP of P. multifida and NH4--N and NO3--N in soils, respectively. Therefore, our results suggest that moderate degradation could weaken the negative effects of warming on reproductive phenophases of K. pygmaea, and that we should take into account grassland degradation and its associated changes in plant species richness and soil inorganic nitrogen when we predict the response of plant phenology to future warming. C1 [Zhang, Lirong; Lv, Wangwang; Jiang, Lili; Li, Bowen; Liu, Peipei; Wang, Qi; Zhou, Yang; Hong, Huan; Wang, A.; Dorji, Tsechoe; Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Cui, Shujuan] Anqing Normal Univ, Anqing, Anhui, Peoples R China. [Luo, Caiyun; Zhang, Zhenhua; Dorji, Tsechoe] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Peoples R China. [Wang, Shiping] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Lv, Wangwang; Li, Bowen; Liu, Peipei; Wang, Qi; Zhou, Yang; Hong, Huan; Wang, A.] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. EM wangsp@itpcas.ac.cn TC 2 Z9 2 PD SEP 15 PY 2020 VL 300 AR 106998 DI 10.1016/j.agee.2020.106998 UT WOS:000540169600016 DA 2023-03-23 ER PT J AU Xu, TL Chen, X Hou, YH Zhu, B AF Xu, Tianle Chen, Xiao Hou, Yanhui Zhu, Biao TI Changes in microbial biomass, community composition and diversity, and functioning with soil depth in two alpine ecosystems on the Tibetan plateau SO PLANT AND SOIL DT Article AB Background and aims Microbial communities play an important regulatory role in soil carbon and nutrient cycling in terrestrial ecosystems. Most studies on microbial communities and biogeochemical cycling focus on surface soils (0-20 cm). However, relatively little is known about how structure and functioning of microbial communities shift with depth in a soil profile, which is crucial to understand biogeochemical cycling in deep soils. Methods We combined a number of complementary techniques to investigate the microbial biomass, community composition and diversity, and potential functioning along soil profile (0-70 cm) in two alpine ecosystems (meadow and shrubland) on the Tibetan Plateau. Results The microbial biomass and fungi:bacteria ratio declined significantly with depth, while the ratio of Gram-positive to Gram-negative bacteria increased with depth in both ecosystems. Microbial community composition showed significant differences among soil depths and between ecosystems. The relative abundance of some phylum of archaea, bacteria or fungi (e.g.Basidiomycota,Bacteroidetes) changed significantly with soil depth and ecosystem type. Bacteria diversity declined with depth, while archaea richness (OTU number) increased with depth and fungi diversity and richness did not show clear trend with depth. The co-occurrence network analysis further showed that surface soil microbes were more connected and interacted among each other compared to deep soil microbes. Moreover, total enzymatic activities and soil C mineralization rate declined with depth in both ecosystems. We also detected shifts with depth in some functional guilds of bacteria (based on faprotax database) in both ecosystems and fungi (based on FUNGuild database) only in shrubland. Conclusions The biomass, community composition and diversity, and potential functioning of microbial communities all shifted significantly along soil profile in both ecosystems, and the vertical patterns of diversity varied among different microbial groups. This may have important implications for carbon and nutrient cycling along the soil profile in alpine ecosystems. C1 [Xu, Tianle; Chen, Xiao; Hou, Yanhui; Zhu, Biao] Peking Univ, Inst Ecol, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. [Xu, Tianle; Chen, Xiao; Hou, Yanhui; Zhu, Biao] Peking Univ, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China. RP Zhu, B (通讯作者)，Peking Univ, Inst Ecol, Coll Urban & Environm Sci, Beijing 100871, Peoples R China.; Zhu, B (通讯作者)，Peking Univ, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China. EM biaozhu@pku.edu.cn TC 21 Z9 21 PD FEB PY 2021 VL 459 IS 1-2 BP 137 EP 153 DI 10.1007/s11104-020-04712-z EA SEP 2020 UT WOS:000568628800001 DA 2023-03-23 ER PT J AU Wang, JF Wu, QB Yuan, ZQ Kang, H AF Wang, Junfeng Wu, Qingbai Yuan, Ziqiang Kang, Hojeong TI Soil respiration of alpine meadow is controlled by freeze-thaw processes of active layer in the permafrost region of the Qinghai-Tibet Plateau SO CRYOSPHERE DT Article AB Freezing and thawing action of the active layer plays a significant role in soil respiration (R-s) in permafrost regions. However, little is known about how the freeze-thaw processes affect the R-s dynamics in different stages of the alpine meadow underlain by permafrost in the Qinghai-Tibet Plateau (QTP). We conducted continuous in situ measurements of R-s and freeze-thaw processes of the active layer at an alpine meadow site in the Beiluhe permafrost region of the QTP and divided the freeze-thaw processes into four different stages in a complete freeze-thaw cycle, comprising the summer thawing (ST) stage, autumn freezing (AF) stage, winter cooling (WC) stage, and spring warming (SW) stage. We found that the freeze-thaw processes have various effects on the Rs dynamics in different freeze-thaw stages. The mean Rs ranged from 0.12 to 3.18 mu molm(-2) s(-1) across the stages, with the lowest value in WC and highest value in ST. Q10 among the different freeze-thaw stages changed greatly, with the maximum (4.91 +/- 0.35) in WC and minimum (0.33 +/- 0.21) in AF. Patterns of R-s among the ST, AF, WC, and SW stages differed, and the corresponding contribution percentages of cumulative R-s to total Rs of a complete freeze-thaw cycle (1692.98 +/- 51.43 gCO(2) m(-2)) were 61.32 +/- 0.32 %, 8.89 +/- 0.18 %, 18.43 +/- 0.11 %, and 11.29 +/- 0.11 %, respectively. Soil temperature (T-s) was the most important driver of Rs regardless of soil water status in all stages. Our results suggest that as climate change and permafrost degradation continue, great changes in freeze-thaw process patterns may trigger more R-s emissions from this ecosystem because of a prolonged ST stage. C1 [Wang, Junfeng; Wu, Qingbai; Yuan, Ziqiang] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. [Wang, Junfeng] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Beiluhe Observat Stn Frozen Soil Environm & Engn, Lanzhou 730000, Peoples R China. [Kang, Hojeong] Yonsei Univ, Sch Civil & Environm Engn, Seoul 03722, South Korea. RP Wu, QB (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China.; Kang, H (通讯作者)，Yonsei Univ, Sch Civil & Environm Engn, Seoul 03722, South Korea. EM qbwu@lzb.ac.cn; hj_kang@yonsei.ac.kr TC 6 Z9 6 PD SEP 3 PY 2020 VL 14 IS 9 BP 2835 EP 2848 DI 10.5194/tc-14-2835-2020 UT WOS:000569332300001 DA 2023-03-23 ER PT J AU Feng, HY Squires, VR AF Feng, Haiying Squires, Victor R. TI Socio-Environmental Dynamics of Alpine Grasslands, Steppes and Meadows of the Qinghai-Tibetan Plateau, China: A Commentary SO APPLIED SCIENCES-BASEL DT Editorial Material AB Alpine grasslands are a common feature on the extensive (2.6 million km(2)) Qinghai-Tibet plateau in western and southwestern China. These grasslands are characterized by their ability to thrive at high altitudes and in areas with short growing seasons and low humidity. Alpine steppe and alpine meadow are the principal plant Formations supporting a rich species mix of grass and forb species, many of them endemic. Alpine grasslands are the mainstay of pastoralism where yaks and hardy Tibetan sheep and Bactrian camels are the favored livestock in the cold arid region. It is not only their importance to local semi nomadic herders, but their role as headwaters of nine major rivers that provide water to more than one billion people in China and in neighboring countries in south and south-east Asia and beyond. Grasslands in this region were heavily utilized in recent decades and are facing accelerated land degradation. Government and herder responses, although quite different, are being implemented as climate change and the transition to the market economy proceeds apace. Problems and prospects for alpine grasslands and the management regimes being imposed (including sedentarization, resettlement and global warming are briefly discussed. C1 [Feng, Haiying] Beibu Gulf Univ, Qinzhou Dev Res Inst, Qinzhou 535011, Peoples R China. [Squires, Victor R.] Univ Adelaide, Fac Nat Resources, Adelaide, SA 5005, Australia. RP Feng, HY (通讯作者)，Beibu Gulf Univ, Qinzhou Dev Res Inst, Qinzhou 535011, Peoples R China.; Squires, VR (通讯作者)，Univ Adelaide, Fac Nat Resources, Adelaide, SA 5005, Australia. EM fhy@bbgu.edu.cn; squires200@yahoo.com.au TC 6 Z9 6 PD SEP PY 2020 VL 10 IS 18 AR 6488 DI 10.3390/app10186488 UT WOS:000581799600001 DA 2023-03-23 ER PT J AU Jia, B Niu, ZQ Wu, YN Kuzyakov, Y Li, XG AF Jia, Bin Niu, Ziqi Wu, Yining Kuzyakov, Yakov Li, Xiao Gang TI Waterlogging increases organic carbon decomposition in grassland soils SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB Drainage increases soil organic carbon (SOC) mineralization, but waterlogging will not necessarily slow the SOC decomposition. We investigated the effects of water regime (anaerobic vs. aerobic conditions) on SOC mineralization in adjacent wetland and grassland soils with contrasting biochemical properties in the east Tibetan Plateau. Biochemical characteristics of SOC (compositions of non-cellulosic and amino polysaccharides) were analyzed, then soils were moistened to 70% of water-holding capacity (aerobic) or saturated (anaerobic) and incubated at 25 degrees C for 95 days. The non-cellulosic sugar content in SOC was similar in wetland and meadow soils, but the mass ratio of hexoses (galactose plus mannose or rhamnose plus fucose) to pentoses (arabinose plus xylose) was three-fold greater in meadows than wetlands. Furthermore, there was three times more accumulation of microbial residues (sum of glucosamine, mannosamine, galactosamine, and muramic acid) in SOC, and more fungal than bacterial necromass in the meadow than wetland soils. This suggests slower transformation of plant litter by microorganisms, and thus less accumulation of microbial products in the SOC of wetlands than meadows. Meadow soils had more microbial biomass and higher activities of beta-glucosidase, phenol oxidase, and urease per unit of SOC than wetland soils. During the 95-day incubation, C loss (as CO2) per unit of SOC was 55-73% greater in anaerobic than aerobic meadow soils, but was 59-64% less from wetland soils under anaerobic conditions than aerobic conditions. Thus, SOC decomposition in anaerobic conditions was dependent on the degree of SOC degradation, which was related to the initial proportion of plant and microbial residues. We addressed the importance of biochemical nature in regulating SOC decomposition under anaerobic conditions. We conclude that both the wetland drainage and grassland waterlogging increase SOC mineralization (measured as CO2 evolution) in alpine areas. C1 [Jia, Bin; Niu, Ziqi; Wu, Yining; Kuzyakov, Yakov; Li, Xiao Gang] Lanzhou Univ, State Key Lab Grassland & Agroecosyst, Sch Life Sci, 222 South Tianshui Rd, Lanzhou 730000, Peoples R China. [Kuzyakov, Yakov] Univ Goettingen, Dept Soil Sci Temperate Ecosyst, Gottingen, Germany. [Kuzyakov, Yakov] Univ Goettingen, Dept Agr Soil Sci, Gottingen, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan 420049, Russia. [Kuzyakov, Yakov] RUDN Univ, Agrotechnol Inst, Moscow 117198, Russia. RP Li, XG (通讯作者)，Lanzhou Univ, State Key Lab Grassland & Agroecosyst, Sch Life Sci, 222 South Tianshui Rd, Lanzhou 730000, Peoples R China. EM lixiaogang@lzu.edu.cn TC 6 Z9 6 PD SEP PY 2020 VL 148 AR 107927 DI 10.1016/j.soilbio.2020.107927 UT WOS:000566668900049 DA 2023-03-23 ER PT J AU Peng, F Xue, X Li, CY Lai, CM Sun, J Tsubo, M Tsunekawa, A Wang, T AF Peng, Fei Xue, Xian Li, Chengyang Lai, Chimin Sun, Jian Tsubo, Mitsuru Tsunekawa, Atsushi Wang, Tao TI Plant community of alpine steppe shows stronger association with soil properties than alpine meadow alongside degradation SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The interaction between soil properties and plant community determines the efficacy to restore the degraded grassland via improving soil properties. We conducted a field survey to investigate the relationship between plant community composition and soil physical and chemical properties alongside different degradation stages of alpine grassland. Results showed that with the increasing severity of degradation, the dominant plants shifted from sedge and graminoid species, respectively, to forbs species in alpine meadow (AM) and alpine steppe (AS). Species richness and diversity indices were unchanged until the severely degraded stage in both AM and AS. Forward selection showed bulk density (BD) and ammonia nitrogen (NH4+) at 1020 cm, pH and the ratio of soil organic carbon to total nitrogen (C/N) at 010 cm were the four important variables being responsible for the species community variation alongside degradation of AS, which explained 18.7% of the total variance. Soil nitrate nitrogen (NO3-) and C/N at 2030 cm, NH4+ at 1020, and BD at 010 cm were the important variables in driving the community variance alongside degradation stages, which only explained 9.5% of the total variance of AM. The loss of dense root layer and the species community change induced change in BD, and difference in plant competition for available resources would lead to the stronger association between vegetation community and soil properties in AS than that in AM. Our results indicate that though improving soil nutrients and soil texture to restore the degraded AS may be more effective than to restore degraded AM. C1 [Peng, Fei; Xue, Xian; Li, Chengyang; Lai, Chimin; Wang, Tao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Gansu, Peoples R China. [Peng, Fei] Tottori Univ, Int Platform Dryland Res & Educ, Tottori, Japan. [Peng, Fei; Xue, Xian] Chinese Acad Sci, Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Beijing, Peoples R China. [Li, Chengyang; Lai, Chimin] Univ Chinese Acad Sci, Beijing, Peoples R China. [Tsubo, Mitsuru; Tsunekawa, Atsushi] Tottori Univ, Arid Land Res Ctr, Tottori, Japan. [Sun, Jian] Chinese Acad Sci, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. RP Peng, F (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Gansu, Peoples R China. EM pengfei@lzb.ac.cn TC 21 Z9 21 PD SEP 1 PY 2020 VL 733 AR 139048 DI 10.1016/j.scitotenv.2020.139048 UT WOS:000540253100009 DA 2023-03-23 ER PT J AU Sun, Y Yi, SH Hou, FJ Luo, DW Hu, JQ Zhou, ZY AF Sun, Yi Yi, Shuhua Hou, Fujiang Luo, Dongwen Hu, Junqi Zhou, Zhaoye TI Quantifying the Dynamics of Livestock Distribution by Unmanned Aerial Vehicles (UAVs): A Case Study of Yak Grazing at the Household Scale SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB Managed grazing is the most extensive land use worldwide. Information about the spatio-temporal distribution of livestock is critical for grassland ecosystem management. However, no direct and cost-effective method exists to monitor livestock distribution under natural conditions. We proposed a practical method that uses unmanned aerial vehicles (UAVs), and tested it at a typical household pasture on the QinghaiTibetan Plateau. We monitored and analyzed the hourly spatial distribution of each yak (Bos mutus). We found that (1) yak information extracted by our independently developed software was sufficiently accurate (P > 0.05); (2) yak density (frequency/area/period) decreased with increasing distance from campsites in the early growing season, while the pattern reversed in the late growing season; (3) dispersion index (DI, m(2)/yak) of the yak herd exhibited a tendency to decrease in the morning and then to increase in the afternoon within a day; from June to September DI decreased in both the morning and afternoon, but was similar at noon. The monitoring method we developed in this study characterized the spatial distribution of the whole yak herd dynamically with high frequency, resolution, and efficiency. We conclude that this method is suitable for long-term monitoring of animal behavior, and for studying relationship between the distribution of pastoral livestock and resource availability, which will be beneficial for grassland sustainable management. (C) 2020 The Society for Range Management. Published by Elsevier Inc. All rights reserved. C1 [Sun, Yi; Yi, Shuhua] Nantong Univ, Inst Fragile Ecoenvironm, 999 Tongjing Rd, Nantong 226007, Jiangsu, Peoples R China. [Sun, Yi; Yi, Shuhua; Hu, Junqi] Nantong Univ, Sch Geog Sci, 999 Tongjing Rd, Nantong 226007, Jiangsu, Peoples R China. [Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Luo, Dongwen] AgResearch Ltd, Grasslands Res Ctr, Palmerston North, New Zealand. [Zhou, Zhaoye] Lanzhou Univ Technol, Sch Civil Engn, Lanzhou 730050, Peoples R China. RP Yi, SH (通讯作者)，Nantong Univ, Inst Fragile Ecoenvironm, 999 Tongjing Rd, Nantong 226007, Jiangsu, Peoples R China. EM yis@ntu.edu.cn TC 10 Z9 10 PD SEP PY 2020 VL 73 IS 5 BP 642 EP 648 DI 10.1016/j.rama.2020.05.004 UT WOS:000569295900009 DA 2023-03-23 ER PT J AU Yang, C Hou, F Sun, Y Yuan, H Liu, Y Zhang, Y Chang, S AF Yang, C. Hou, F. Sun, Y. Yuan, H. Liu, Y. Zhang, Y. Chang, S. TI Oats hay supplementation to yak grazing alpine meadow improves carbon return to the soil of grassland ecosystem on the Qinghai-Tibet Plateau, China SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Supplementation of livestock feed is a common strategy for improving animal production in pasture-based systems worldwide. On the Qinghai-Tibet Plateau of China, however, the grassland ecosystem is fragile and therefore sensitive to disruption by external forces. We therefore investigated the effects of supplementing yaks feed with oats hay on animal production, forage biomass, and carbon return in litter and dung as well as the effects on soil organic carbon stock. Two grazing systems-native grazing, or grazing with hay supplementation-were established in 2010. For the native grazing system, yaks were rotationally grazed in two paddocks (3.3 yaks/ha) with each 15 days during the warm season (July through October) and 20 days during the cold season (November through June). The hay supplementation system was the same as the native system except that each yak also received oats hay (1.5 kg/day, dry matter basis) during the cold season. For each system, yak growth, forage biomass of the pasture, carbon return from litter and dung to soil, and soil organic carbon stock were measured from 2010 to 2014. The yaks supplemented with oats hay had greater growth performance compared with non supplemented animals, thereby providing economic benefits for herdsmen. With respect to carbon cycling, supplementation increased carbon return in litter and dung and consequently reduced the soil carbon stock loss. The results indicate that supplementation with oats hay positively impacted forage production and carbon cycling in alpine meadows and thus may help remediate degraded soils and improve grassland utilization on the Qinghai-Tibet Plateau. (C) 2020 The Author(s). Published by Elsevier B.V. C1 [Yang, C.; Hou, F.; Sun, Y.; Yuan, H.; Liu, Y.; Zhang, Y.; Chang, S.] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Minist Agr,State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. RP Hou, F (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Minist Agr,State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. EM cyhoufj@lzu.edu.cn TC 7 Z9 8 PD SEP PY 2020 VL 23 AR e01158 DI 10.1016/j.gecco.2020.e01158 UT WOS:000568728500005 DA 2023-03-23 ER PT J AU He, MR Xin, CM Baskin, CC Li, JH Zhao, YP An, H Sheng, XJ Zhao, L Zhao, Y Ma, MJ AF He, Mingrui Xin, Chunming Baskin, Carol C. Li, Jinghua Zhao, Yunpeng An, Hang Sheng, Xiongjie Zhao, Liang Zhao, Yin Ma, Miaojun TI Different response of transient and persistent seed bank of alpine wetland to grazing disturbance on the Tibetan Plateau SO PLANT AND SOIL DT Article AB Background With increased grazing disturbance of wetlands, soil moisture decreases, which could have an effect on the seed bank. The seed bank is a crucial resource for vegetation restoration; however, the effects of grazing disturbance on density and richness of seed banks and consequences on restoration of degraded wetlands are unclear. Methods We selected six alpine wetlands along a degradation gradient on the Tibetan Plateau for study. The structural equation model was used to explore the direct and indirect effects of soil moisture on transient and persistent seed banks through soil physicochemical factors and vegetation. Non-metric multidimensional scaling was used to explore the role of seed banks in alpine wetland vegetation regeneration. Results A decrease in soil moisture directly increased richness and density of the transient seed bank. However, decreased soil moisture indirectly decreased density of transient and increased richness and density of the persistent seed bank though soil pH and richness and abundance of vegetation. The similarity between the seed bank and vegetation increased with wetland degradation. Slope of the Bray-Curtis dissimilarity between transient seed bank and vegetation was higher than that for the persistent seed bank and vegetation. Conclusions Transient seed banks remained almost constant under grazing disturbance, which favours persistent seed bank formation. Transient and persistent seed banks were determined by aboveground vegetation and soil environment, respectively. Seed banks provide strong resistance and resilience to degradation of wetland ecosystems, while persistent seed banks play a more important role than transient seed banks in restoration of degraded alpine wetlands. C1 [He, Mingrui; Xin, Chunming; Li, Jinghua; Zhao, Yunpeng; An, Hang; Sheng, Xiongjie; Zhao, Liang; Zhao, Yin; Ma, Miaojun] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Peoples R China. [Baskin, Carol C.] Univ Kentucky, Dept Biol, Lexington, KY 40506 USA. [Baskin, Carol C.] Univ Kentucky, Dept Plant & Soil Sci, Lexington, KY 40546 USA. RP Ma, MJ (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Peoples R China. EM hemr18@lzu.edu.cn; xinchm17@lzu.edu.cn; ccbask0@uky.edu; jinhuali@lzu.edu.cn; zhaoyp17@lzu.edu.cn; anh17@lzu.edu.cn; shengxj18@lzu.edu.cn; chersvip@163.com; 782383986@qq.com; mamiaojun@gmail.com TC 11 Z9 11 PD FEB PY 2021 VL 459 IS 1-2 BP 93 EP 107 DI 10.1007/s11104-020-04632-y EA AUG 2020 UT WOS:000556642900006 DA 2023-03-23 ER PT J AU Chen, SY Li, XF Wu, TH Xue, K Luo, DL Wang, XM Wu, QB Kang, SC Zhou, HK Wei, DX AF Chen, Shengyun Li, Xiangfei Wu, Tonghua Xue, Kai Luo, Dongliang Wang, Xiaoming Wu, Qingbai Kang, Shichang Zhou, Huakun Wei, Dengxian TI Soil thermal regime alteration under experimental warming in permafrost regions of the central Tibetan Plateau SO GEODERMA DT Article AB Soil thermal regime in permafrost regions is sensitive to climate change and may cause vast ecological consequences under future warming scenarios. However, there still lacks a systematic evaluation on the effect of warming on soil thermodynamics in the different ecosystems of permafrost regions. This study investigated the alterations of soil thermodynamics in alpine swamp meadow and alpine steppe under experimental warming by open-top chambers in permafrost regions of the central Tibetan Plateau. The results showed that air temperature increased significantly with an annual mean increase of 1.4 degrees C under warming. Compared to alpine swamp meadow, soil thermodynamics represented by soil temperature, soil thermal parameters, soil freeze-thaw process and active layer thickness in alpine steppe was more susceptible to warming. Specifically, soil temperature at 5-40 cm depths increased more in alpine steppe than alpine swamp meadow under warming, especially at topsoil (5-20 cm). Moreover, the increase in soil temperature at topsoil was greater during cold season than warm season. Greater alterations of soil thermal parameters were likely because soil moisture content reduced more in alpine steppe. Regarding soil freeze-thaw process, warming significantly postponed the onset of completely frozen stage and reduced the completely frozen days in alpine steppe. Active layer thickness in alpine steppe distinctly increased by 46 cm on average and showed an increasing trend under warming from 2009 to 2011. Overall, vegetation coverage and soil moisture content were responsible for the different responses of soil thermodynamics to experimental warming. The study has important implications for future scenarios as permafrost and grassland degradation may intensify under climate warming. C1 [Chen, Shengyun; Li, Xiangfei; Wu, Tonghua; Wang, Xiaoming; Kang, Shichang] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou 730000, Gansu, Peoples R China. [Chen, Shengyun] Acad Plateau Sci & Sustainabil, Qinghai Res Ctr Qilian Mt Natl Pk, Xining 810008, Qinghai, Peoples R China. [Chen, Shengyun] Qinghai Normal Univ, Xining 810008, Qinghai, Peoples R China. [Li, Xiangfei; Xue, Kai] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Xue, Kai] Chinese Acad Sci, Key Lab Environm Biotechnol, Beijing 100085, Peoples R China. [Xue, Kai] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Luo, Dongliang; Wu, Qingbai] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Lanzhou 730000, Gansu, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Reg Qinghai, Xining 810008, Qinghai, Peoples R China. [Wei, Dengxian] Forest Seedling Stn Qinghai Prov, Xining 810008, Qinghai, Peoples R China. RP Chen, SY (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou 730000, Gansu, Peoples R China.; Xue, K (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM sychen@lzb.ac.cn; xuekai@ucas.ac.cn TC 14 Z9 15 PD AUG 1 PY 2020 VL 372 AR 114397 DI 10.1016/j.geoderma.2020.114397 UT WOS:000535713600010 DA 2023-03-23 ER PT J AU Deng, BL Zheng, LY Ma, YC Zhang, L Liu, XJ Zhang, XL Zhang, WY Huang, W Hu, XF Guo, XM Siemann, E AF Deng, Bangliang Zheng, Liya Ma, Yingchao Zhang, Ling Liu, Xiaojun Zhang, Xueling Zhang, Wenyuan Huang, Wei Hu, Xiaofei Guo, Xiaomin Siemann, Evan TI Effects of mixing biochar on soil N2O, CO2, and CH(4)emissions after prescribed fire in alpine meadows of Wugong Mountain, China SO JOURNAL OF SOILS AND SEDIMENTS DT Article; Proceedings Paper CT 4th Asia Pacific Biochar Conference (APBC) - Advances in Biochar Research and Applications CY NOV 03-08, 2018 CL Foshan, PEOPLES R CHINA AB Purpose Prescribed fires or wildfires are common in natural ecosystems. Biochar input during fires can impact soil greenhouse gas (GHG) emissions, including methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O). Meadows are functionally important ecosystems due to their large carbon (C) and nitrogen (N) stocks and potential to mitigate GHG emissions. The effects of biochar on meadow GHG emissions may be sensitive to whether it is derived from more than one type of vegetation, especially with N addition and warming. To further our understanding of how input of fire-derived biochar affects meadow soil GHG emissions, especially under the context of N deposition and warming, we conducted this study to examine potential non-additive effects of these factors. Materials and methods We collected soils from meadows dominated byMiscanthus sinensisandArundinella hirtaat Wugong Mountain (Jiangxi, China). Biochar was produced by pyrolyzing the aboveground vegetation of each of the two species at 450 degrees C for 1 h. Mixed biochar was produced by 1:1 ratio. Soil GHG emissions and N transformations were measured by incubating soils with biochar (control,M. sinensisbiochar,A. hirtabiochar, mixed biochar) and N addition (control vs. 6 g m(-2)) treatments at different temperatures (10, 15, 20, or 25 degrees C). Results and discussion Biochar input consistently increased both CH(4)and N2O flux, but onlyA. hirtaand mixed biochar decreased CO(2)emission rates. Mixed biochar imposed non-additive effects on cumulative CH(4)and CO(2)emissions. Biochar decreased soil nitrification rates and increased the temperature sensitivity of soil N2O emission rates. The results indicated that biochar input during fires in meadows impacts soil GHG emissions and N transformations. Input of biochar into meadow soil following fire impacted GHG emissions, and mixing biochar derived from different species imposed non-additive effects on CH(4)and CO(2)emissions. Conclusions The variable and non-additive biochar effects on soil GHG emissions showed that fire-induced alterations in meadow soil GHG emissions will depend on the species composition of the local plant community. The effects of biochar on meadow soil GHG emissions after fires should be considered in future budgets of meadow soil GHG emissions and prediction of prescribed fire impacts on meadow ecosystems under the context of N deposition and warming. C1 [Deng, Bangliang; Zheng, Liya; Zhang, Ling; Liu, Xiaojun; Zhang, Xueling; Zhang, Wenyuan; Huang, Wei; Guo, Xiaomin] Jiangxi Agr Univ, Coll Forestry, Key Lab Silviculture, Nanchang 330045, Jiangxi, Peoples R China. [Ma, Yingchao] Guangzhou Huali Sci & Technol Vocat Coll, Guangzhou 511325, Peoples R China. [Hu, Xiaofei] Nanchang Univ, Sch Management, Nanchang 330031, Jiangxi, Peoples R China. [Siemann, Evan] Rice Univ, Dept Biosci, Houston, TX 77005 USA. RP Zhang, L (通讯作者)，Jiangxi Agr Univ, Coll Forestry, Key Lab Silviculture, Nanchang 330045, Jiangxi, Peoples R China. EM lingzhang09@126.com TC 9 Z9 10 PD AUG PY 2020 VL 20 IS 8 SI SI BP 3062 EP 3072 DI 10.1007/s11368-019-02552-8 UT WOS:000549725300006 DA 2023-03-23 ER PT J AU Wang, R Dong, ZB Zhou, ZC AF Wang Rui Dong Zhibao Zhou Zhengchao TI Different Responses of Vegetation to Frozen Ground Degradation in the Source Region of the Yellow River from 1980 to 2018 SO CHINESE GEOGRAPHICAL SCIENCE DT Article AB Frozen ground degradation under a warming climate profoundly influences the growth of alpine vegetation in the source region of the Qinghai-Tibet Plateau. This study investigated spatiotemporal variations in the frozen ground distribution, the active layer thickness (ALT) of permafrost (PF) soil and the soil freeze depth (SFD) in seasonally frozen soil from 1980 to 2018 using the temperature at the top of permafrost (TTOP) model and Stefan equation. We compared the effects of these variations on vegetation growth among different frozen ground types and vegetation types in the source region of the Yellow River (SRYR). The results showed that approximately half of the PF area (20.37% of the SRYR) was projected to degrade into seasonally frozen ground (SFG) during the past four decades; furthermore, the areal average ALT increased by 3.47 cm/yr, and the areal average SFD decreased by 0.93 cm/yr from 1980 to 2018. Accordingly, the growing season Normalized Difference Vegetation Index (NDVI) presented an increasing trend of 0.002/10yr, and the increase rate and proportion of areas with NDVI increase were largest in the transition zone where PF degraded to SFG (the PF to SFG zone). A correlation analysis indicated that variations in ALT and SFD in the SRYR were significantly correlated with increases of NDVI in the growing season. However, a rapid decrease in SFD (< -1.4 cm/10yr) could have reduced the soil moisture and, thus, decreased the NDVI. The NDVI for most vegetation types exhibited a significant positive correlation with ALT and a negative correlation with SFD. However, the steppe NDVI exhibited a significant negative correlation with the SFD in the PF to SFG zone but a positive correlation in the SFG zone, which was mainly limited by water condition because of different change rates of the SFD. C1 [Wang Rui; Dong Zhibao; Zhou Zhengchao] Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Peoples R China. RP Dong, ZB (通讯作者)，Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Peoples R China. EM zbdong@snnu.edu.cn TC 5 Z9 7 PD AUG PY 2020 VL 30 IS 4 BP 557 EP 571 DI 10.1007/s11769-020-1135-y UT WOS:000548683100001 DA 2023-03-23 ER PT J AU Xiao, X Zhang, F Che, T Shi, XN Zeng, C Wang, GX AF Xiao, Xiong Zhang, Fan Che, Tao Shi, Xiaonan Zeng, Chen Wang, Guanxing TI Changes in plot-scale runoff generation processes from the spring-summer transition period to the summer months in a permafrost-dominated catchment SO JOURNAL OF HYDROLOGY DT Article AB The hydrological regimes in permafrost-dominated catchments have unique characteristics. However, studies based on plot-scale experiments of runoff generation processes and the factors influencing these processes are limited on the Tibetan Plateau, which is experiencing rapid warming and permafrost degradation. Runoff generation processes were studied on a standard runoff plot (5 x 20 m) in a permafrost-dominated catchment on the Tibetan Plateau with an alpine meadow cover to analyze these processes during the spring-summer transition period (from mid-May to early June) and in the summer months of June and July. The discharge, including surface and subsurface runoff, the soil hydrothermal and moisture conditions, and the meteorological conditions were monitored from May 2018 to May 2019. Partial Least-Squares Path Modeling was used to identify the influencing factors in the two time periods. The lateral subsurface flow at 30-60 cm depth accounted for the majority of the discharge from the runoff plot ( > 99%) and showed a sharp increase when the soil water contents of the thawed soil layers exceeded a threshold value that varied from 0.41 to 0.52. During the spring-summer transition period, the lateral subsurface flow at 30-60 cm depth was promoted by both event precipitation and the antecedent precipitation with an average runoff ratio of 1.7, indicating that the antecedent moisture condition maintained by the underlying permafrost drives runoff generation via meltwater from snow and frozen soil. In the summer months, the lateral subsurface flow at 30-60 cm depth was directly promoted by event precipitation, especially the moderate precipitation that occurred in this period, with a reduced runoff ratio of 0.5 as a result of deepening of the thawed soil layer from 30 to > 60 cm, enhanced evapotranspiration and an increased soil water storage capacity caused by an increase of air temperature and the soil temperature. Prediction models obtained via Multiple Linear Regressions of the identified influencing factors were able to accurately estimate the discharge. This study shows the important role of lateral subsurface flow in runoff generation processes in this permafrost area and the most important influencing factors in different seasons. C1 [Xiao, Xiong; Zhang, Fan; Shi, Xiaonan; Zeng, Chen; Wang, Guanxing] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing, Peoples R China. [Xiao, Xiong; Zhang, Fan; Che, Tao; Shi, Xiaonan; Wang, Guanxing] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing, Peoples R China. [Xiao, Xiong; Zhang, Fan; Wang, Guanxing] Univ Chinese Acad Sci, Beijing, Peoples R China. [Che, Tao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou, Peoples R China. RP Zhang, F (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing, Peoples R China. EM zhangfan@itpcas.ac.cn TC 10 Z9 11 PD AUG PY 2020 VL 587 AR 124966 DI 10.1016/j.jhydrol.2020.124966 UT WOS:000568819100035 DA 2023-03-23 ER PT J AU Ye, CC Sun, J Liu, M Xiong, JN Zong, N Hu, J Huang, Y Duan, XW Tsunekawa, A AF Ye, Chongchong Sun, Jian Liu, Miao Xiong, Junnan Zong, Ning Hu, Jian Huang, Yong Duan, Xingwu Tsunekawa, Atsushi TI Concurrent and Lagged Effects of Extreme Drought Induce Net Reduction in Vegetation Carbon Uptake on Tibetan Plateau SO REMOTE SENSING DT Article AB Climatic extremes have adverse concurrent and lagged effects on terrestrial carbon cycles. Here, a concurrent effect refers to the occurrence of a latent impact during climate extremes, and a lagged effect appears sometime thereafter. Nevertheless, the uncertainties of these extreme drought effects on net carbon uptake and the recovery processes of vegetation in different Tibetan Plateau (TP) ecosystems are poorly understood. In this study, we calculated the Standardised Precipitation-Evapotranspiration Index (SPEI) based on meteorological datasets with an improved spatial resolution, and we adopted the Carnegie-Ames-Stanford approach model to develop a net primary production (NPP) dataset based on multiple datasets across the TP during 1982-2015. On this basis, we quantised the net reduction in vegetation carbon uptake (NRVCU) on the TP, investigated the spatiotemporal variability of the NPP, NRVCU and SPEI, and analysed the NRVCUs that are caused by the concurrent and lagged effects of extreme drought and the recovery times in different ecosystems. According to our results, the Qaidam Basin and most forest regions possessed a significant trend towards drought during 1982-2015 (withSlopeof SPEI < 0,P< 0.05), and the highest frequency of extreme drought events was principally distributed in the Qaidam Basin, with three to six events. The annual total net reduction in vegetation carbon uptake on the TP experienced a significant downward trend from 1982 to 2015 (-0.0018 +/- 0.0002 PgC year(-1),P< 0.001), which was negatively correlated with annual total precipitation and annual mean temperature (P< 0.05). In spatial scale, the NRVCU decrement was widely spread (approximately 55% of grids) with 17.86% of the area displaying significant declining trends (P< 0.05), and the sharpest declining trend (Slope <= -2) was mainly concentrated in southeastern TP. For the alpine steppe and alpine meadow ecosystems, the concurrent and lagged effects of extreme drought induced a significant difference in NRVCU (P< 0.05), while forests presented the opposite results. The recovery time comparisons from extreme drought suggest that forests require more time (27.62% of grids >= 6 years) to recover their net carbon uptakes compared to grasslands. Therefore, our results emphasise that extreme drought events have stronger lagged effects on forests than on grasslands on the TP. The improved resilience of forests in coping with extreme drought should also be considered in future research. C1 [Ye, Chongchong; Xiong, Junnan] Southwest Petr Univ, Sch Civil Engn & Geomat, Chengdu 610500, Peoples R China. [Ye, Chongchong; Sun, Jian; Liu, Miao; Zong, Ning] Chinese Acad Sci, Synth Res Ctr Chinese Ecosyst Res Network, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Hu, Jian] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. [Huang, Yong; Duan, Xingwu] Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming 650091, Yunnan, Peoples R China. [Tsunekawa, Atsushi] Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. RP Sun, J (通讯作者)，Chinese Acad Sci, Synth Res Ctr Chinese Ecosyst Res Network, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM yechongchong@stu.swpu.edu.cn; sunjian@igsnrr.ac.cn; liumiao@igsnrr.ac.cn; xiongjn@swpu.edu.cn; zongning@igsnrr.ac.cn; jianhu@swun.edu.cn; huangyong@ynu.edu.cn; xwduan@ynu.edu.cn; tsunekawa@tottori-u.ac.jp TC 23 Z9 25 PD AUG PY 2020 VL 12 IS 15 AR 2347 DI 10.3390/rs12152347 UT WOS:000559081500001 DA 2023-03-23 ER PT J AU Peng, Z Xiao, H He, X Xu, CL Pan, TT Yu, XJ AF Peng, Zhen Xiao, Hong He, Xiang Xu, Changlin Pan, Taotao Yu, Xiaojun TI Different levels of rainfall and trampling change the reproductive strategy of Kobresia humilis in the Qinghai-Tibet Plateau SO RANGELAND JOURNAL DT Article AB The sedgeKobresia humilis(C.A. Mey. ex Trautv.) Serg. is the dominant plant in the alpine meadows of China's Qinghai-Tibet Plateau, which has experienced substantial grassland degradation due to reduced rainfall and overgrazing. In this study we sought to determine the reproductive strategy ofK. humilisunder three levels of rainfall and seven levels of trampling by Tibetan sheep and yaks with a two year simulation trial on the Plateau. With a reduction in rainfall and an increase in trampling intensity, there was a decrease in sexual reproduction indices, plant height and single leaf number. The highest rainfall promoted sexual reproduction, whereas average rainfall was conducive to vegetative reproduction, and the lowest rainfall inhibited reproduction. The reproductive strategy ofK. humiliscould be judged according to the average rainfall from July to August. Notably, after two years of low rainfall and a heavy trampling treatment,K. humilisproduced more seeds with smaller size. The rainfall presented a two-way regulation function in the trampling effect onK. humilisreproductive characteristics. C1 [Peng, Zhen; Xiao, Hong; He, Xiang; Xu, Changlin; Pan, Taotao; Yu, Xiaojun] Gansu Agr Univ, Coll Grassland Sci, Lanzhou 730070, Gansu, Peoples R China. [Peng, Zhen; Xiao, Hong; He, Xiang; Xu, Changlin; Pan, Taotao; Yu, Xiaojun] Minist Educ, Key Lab Grassland Ecosyst, Lanzhou 730070, Gansu, Peoples R China. [Peng, Zhen; Xiao, Hong; He, Xiang; Xu, Changlin; Pan, Taotao; Yu, Xiaojun] Sino US Ctr Grassland Ecosyst Sustainabil, Lanzhou 730070, Gansu, Peoples R China. RP Yu, XJ (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Lanzhou 730070, Gansu, Peoples R China.; Yu, XJ (通讯作者)，Minist Educ, Key Lab Grassland Ecosyst, Lanzhou 730070, Gansu, Peoples R China.; Yu, XJ (通讯作者)，Sino US Ctr Grassland Ecosyst Sustainabil, Lanzhou 730070, Gansu, Peoples R China. EM yuxj@gsau.edu.cn TC 1 Z9 1 PY 2020 VL 42 IS 2 BP 143 EP 152 DI 10.1071/RJ19076 EA JUL 2020 UT WOS:000553195200001 DA 2023-03-23 ER PT J AU Zhang, ZC Sun, J Liu, M Xu, M Wang, Y Wu, GL Zhou, HK Ye, CC Tsechoe, D Wei, TX AF Zhang, Zhenchao Sun, Jian Liu, Miao Xu, Ming Wang, Yi Wu, Gao-lin Zhou, Huakun Ye, Chongchong Tsechoe, Dorji Wei, Tianxing TI Don't judge toxic weeds on whether they are native but on their ecological effects SO ECOLOGY AND EVOLUTION DT Review AB The sharp rise in anthropogenic activities and climate change has caused the extensive degradation of grasslands worldwide, jeopardizing ecosystem function, and threatening human well-being. Toxic weeds have been constantly spreading in recent decades; indeed, their occurrence is considered to provide an early sign of land degeneration. Policymakers and scientific researchers often focus on the negative effects of toxic weeds, such as how they inhibit forage growth, kill livestock, and cause economic losses. However, toxic weeds can have several potentially positive ecological impacts on grasslands, such as promoting soil and water conservation, improving nutrient cycling and biodiversity conservation, and protecting pastures from excessive damage by livestock. We reviewed the literature to detail the adaptive mechanisms underlying toxic weeds and to provide new insight into their roles in degraded grassland ecosystems. The findings highlight that the establishment of toxic weeds may provide a self-protective strategy of degenerated pastures that do not require special interventions. Consequently, policymakers, managers, and other personnel responsible for managing grasslands need to take appropriate actions to assess the long-term trade-offs between the development of animal husbandry and the maintenance of ecological services provided by grasslands. C1 [Zhang, Zhenchao; Sun, Jian; Liu, Miao; Xu, Ming; Wang, Yi; Ye, Chongchong] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Zhang, Zhenchao; Wu, Gao-lin] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling, Shaanxi, Peoples R China. [Sun, Jian; Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Area, Xining, Peoples R China. [Xu, Ming] Rutgers State Univ, Sch Environm & Biol Sci, Dept Ecol Evolut & Nat Resources, New Brunswick, NJ USA. [Tsechoe, Dorji] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. [Wei, Tianxing] Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing, Peoples R China. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. EM sunjian@igsnrr.ac.cn TC 13 Z9 15 PD SEP PY 2020 VL 10 IS 17 BP 9014 EP 9025 DI 10.1002/ece3.6609 EA JUL 2020 UT WOS:000553238600001 DA 2023-03-23 ER PT J AU An, H Zhao, YP Ma, MJ AF An, Hang Zhao, Yunpeng Ma, Miaojun TI Precipitation controls seed bank size and its role in alpine meadow community regeneration with increasing altitude SO GLOBAL CHANGE BIOLOGY DT Article AB The Tibetan Plateau has undergone significant climate warming in recent decades, and precipitation has also become increasingly variable. Much research has explored the effects of climate change on vegetation on this plateau. As potential vegetation buried in the soil, the soil seed bank is an important resource for ecosystem restoration and resilience. However, almost no studies have explored the effects of climate change on seed banks and the mechanisms of these effects. We used an altitudinal gradient to represent a decrease in temperature and collected soil seed bank samples from 27 alpine meadows (3,158-4,002 m) along this gradient. A structural equation model was used to explore the direct effects of mean annual precipitation (MAP) and mean annual temperature (MAT) on the soil seed bank and their indirect effects through aboveground vegetation and soil environmental factors. The species richness and abundance of the aboveground vegetation varied little along the altitudinal gradient, while the species richness and density of the seed bank decreased. The similarity between the seed bank and aboveground vegetation decreased with altitude; specifically, it decreased with MAP but was not related to MAT. The increase in MAP with increasing altitude directly decreased the species richness and density of the seed bank, while the increase in MAP and decrease in MAT with increasing altitude indirectly increased and decreased the species richness of the seed bank, respectively, by directly increasing and decreasing the species richness of the plant community. The size of the soil seed bank declined with increasing altitude. Increases in precipitation directly decreased the species richness and density and indirectly decreased the species richness of the seed bank with increasing elevation. The role of the seed bank in aboveground plant community regeneration decreases with increasing altitude, and this process is controlled by precipitation but not temperature. C1 [An, Hang; Zhao, Yunpeng; Ma, Miaojun] Lanzhou Univ, State Key Lab Grassland & Agroecosyst, Sch Life Sci, Lanzhou 730000, Gansu, Peoples R China. RP Ma, MJ (通讯作者)，Lanzhou Univ, State Key Lab Grassland & Agroecosyst, Sch Life Sci, Lanzhou 730000, Gansu, Peoples R China. EM mjma@lzu.edu.cn TC 20 Z9 23 PD OCT PY 2020 VL 26 IS 10 BP 5767 EP 5777 DI 10.1111/gcb.15260 EA JUL 2020 UT WOS:000550896200001 DA 2023-03-23 ER PT J AU Wang, LM Li, MY Wang, JX Li, XG Wang, LC AF Wang, Liuming Li, Mengyao Wang, Junxiao Li, Xingong Wang, Lachun TI An analytical reductionist framework to separate the effects of climate change and human activities on variation in water use efficiency SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Ecosystem water use efficiency (WUE) is a key indicator that depicts the carbon-water coupling relationship in terrestrial ecosystems. Separating the effects of climate change and human activities to the variation in WUE are essential for water resources and ecosystem management, especially for fragile ecosystems such as the Tibetan Plateau (TP). In this study, we introduced an analytical framework that combined the attribution approach with the elastic coefficient separation method to assess the impact of climate change and human activities on WUE variation in the TP from 1982 to 2015. The results are the following: (1) the multiyear mean annual WUE over the TP was 0.65 g C.kg(-1) H2O and had a slightly increasing trend with a slope of 0.004 g C.kg(-1) H2O yr(-1) with about 87% of the vegetated area showed increasing trend. (2) WUE was positively correlated with temperature, precipitation and air pressure. The northwest TP tends to be a water-limited condition, while the thermal stress is spatially universal in the TP, climate warming and wetting promoted the gross primary productivity (GPP) and WUE enhancement in the TP. (3) WUE was more sensitive to GPP, and variation in WUE was mainly contributed by GPP. Climate change and human activities tend to cause more variations in GPP rather than evapotranspiration (ET), but great differences exist for different regions and vegetation types. (4) There was a good consistency between the WUE variation calculated by the framework and the actual WUE variation (R-2 = 0.95). Climate change dominated the increase of WUE in the TP with a contribution rate of 79.8%, while human activities tend to reduce WUE (-20.2%). Ecological projects played a positive role in the ecological restoration of the TP, but there may be other human activities, which caused ecological degradation, that may need more attention in future ecological protections. (C) 2020 Elsevier B.V. All rights reserved. C1 [Wang, Liuming; Li, Mengyao; Wang, Junxiao; Wang, Lachun] Nanjing Univ, Sch Geog & Ocean Sci, Nanjing 210023, Peoples R China. [Wang, Liuming; Li, Mengyao; Wang, Junxiao] Minist Nat Resource, Key Lab Coastal Zone Exploitat & Protect, Nanjing 210023, Peoples R China. [Li, Xingong] Univ Kansas, Dept Geog & Atmospher Sci, Lawrence, KS 66045 USA. RP Li, XG (通讯作者)，Univ Kansas, Dept Geog & Atmospher Sci, Lawrence, KS 66045 USA. EM lixi@ku.edu TC 31 Z9 31 PD JUL 20 PY 2020 VL 727 AR 138306 DI 10.1016/j.scitotenv.2020.138306 UT WOS:000537409800014 DA 2023-03-23 ER PT J AU Zhu, JT Zhang, YJ Yang, X Chen, N Jiang, L AF Zhu, Juntao Zhang, Yangjian Yang, Xian Chen, Ning Jiang, Lin TI Synergistic effects of nitrogen and CO(2)enrichment on alpine grassland biomass and community structure SO NEW PHYTOLOGIST DT Article AB Global environmental change is altering the Earth's ecosystems. However, much research has focused on ecosystem-level responses, and we know substantially less about community-level responses to global change stressors. Here we conducted a 6-yr field experiment in a high-altitude (4600 m asl) alpine grassland on the Tibetan Plateau to explore the effects of nitrogen (N) addition and rising atmospheric CO(2)concentration on plant communities. Our results showed that N and CO(2)enrichment had synergistic effects on alpine grassland communities. Adding nitrogen or CO(2)alone did not alter total community biomass, species diversity or community composition, whereas adding both resources together increased community biomass, reduced species diversity and altered community composition. The observed decline in species diversity under simultaneous N and CO(2)enrichment was associated with greater community biomass and lower soil water content, and driven by the loss of species characterised simultaneously by tall stature and small specific leaf area. Our findings point to the co-limitation of alpine plant community biomass and structure by nitrogen and CO2, emphasising the need for future studies to consider multiple aspects of global environmental change together to gain a more complete understanding of their ecological consequences. C1 [Zhu, Juntao; Zhang, Yangjian; Chen, Ning] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Rizearch Stn, Beijing 100101, Peoples R China. [Zhu, Juntao; Yang, Xian; Jiang, Lin] Georgia Inst Technol, Sch Biol Sci, Atlanta, GA 30332 USA. [Zhang, Yangjian] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhang, Yangjian] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. RP Zhang, YJ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Rizearch Stn, Beijing 100101, Peoples R China.; Jiang, L (通讯作者)，Georgia Inst Technol, Sch Biol Sci, Atlanta, GA 30332 USA.; Zhang, YJ (通讯作者)，CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China.; Zhang, YJ (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. EM lin.jiang@biology.gatech.edu TC 12 Z9 12 PD NOV PY 2020 VL 228 IS 4 BP 1283 EP 1294 DI 10.1111/nph.16767 EA JUL 2020 UT WOS:000548590300001 DA 2023-03-23 ER PT J AU Chen, DD Li, Q Liu, Z He, FQ Chen, X Xu, SX Zhao, XQ Zhao, L AF Chen, Dongdong Li, Qi Liu, Zhe He, Fuquan Chen, Xin Xu, Shixiao Zhao, Xinquan Zhao, Liang TI Variations of Forage Yield and Nutrients with Altitude Gradients and Their Influencing Factors in Alpine Meadow of Sanjiangyuan, China SO JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION DT Article AB This study aimed to investigate the forage yield and quality and extract factors affecting them and provide scientific support for ecological protection of alpine grassland and sustainable development of animal husbandry in the Qinghai-Tibetan Plateau. Samples were collected in late August (peak of the growing season) 2014 in two mountain transects (Laji mountain, 36 degrees 21 ' N, 101 degrees 27 ' E, 3389-3876 m a.s.l. and Heitu mountain, 34 degrees 22 ' N, 100 degrees 30 ' E, 4121-4268 m a.s.l.) of Sanjiangyuan. Forage biomass and nutrients were measured by the national standard method, and influencing factors were extracted by RDA. Results showed that the forage yield decreased significantly with the increasing altitude, no matter in the mountain > 4000 m a.s.l. or < 4000 m a.s.l. Forage yield was more affected by environmental factors in low altitude areas, but less in high-altitude areas. Forage nutrients were mainly affected by altitude and soil organic carbon (SOC) (p < 0.01) on the mountain < 4000 m a.s.l., while on the mountain > 4000 m a.s.l., fiber and lignin were mainly affected by soil pH and SOC and crude protein (CP) by soil pH (p < 0.05) and total phosphorus (TP). Overall, with the increasing altitude, forage CP and fat (CF) increased, while neutral detergent fiber and acid detergent fiber decreased, implying that warming may lead to the decline of forage quality and then affect the safety of animal husbandry. Moreover, forage CP and CF were also affected by soil inorganic nitrogen and TP rather than SOC and soil total nitrogen. C1 [Chen, Dongdong; Li, Qi; He, Fuquan; Chen, Xin; Xu, Shixiao; Zhao, Xinquan; Zhao, Liang] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Northwest Inst Plateau Biol, Xining 810008, Qinghai, Peoples R China. [Chen, Dongdong; Li, Qi; He, Fuquan; Chen, Xin; Xu, Shixiao; Zhao, Xinquan; Zhao, Liang] Chinese Acad Sci, Inst Sanjiangyuan Natl Pk, Xining 810008, Peoples R China. [Liu, Zhe] Shandong Univ Arts, Jinan 250014, Shandong, Peoples R China. [Chen, Xin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Zhao, XQ; Zhao, L (通讯作者)，Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Northwest Inst Plateau Biol, Xining 810008, Qinghai, Peoples R China.; Zhao, XQ; Zhao, L (通讯作者)，Chinese Acad Sci, Inst Sanjiangyuan Natl Pk, Xining 810008, Peoples R China. EM chendd@nwipb.cas.cn; xqzhao@nwipb.cas.cn; lzhao@nwipb.cas.cn TC 1 Z9 1 PD DEC PY 2020 VL 20 IS 4 BP 2164 EP 2174 DI 10.1007/s42729-020-00284-0 EA JUL 2020 UT WOS:000548791000001 DA 2023-03-23 ER PT J AU Chu, B Ye, GH Yang, SW Zhou, FF Zhang, FY Zhou, JW Hua, LM AF Chu, Bin Ye, Guohui Yang, Siwei Zhou, Fufei Zhang, Feiyu Zhou, Jianwei Hua, Limin TI Effect of Plateau Zokor (Myospalax fontanierii) Disturbance on Plant Community Structure and Soil Properties in the Eastern Qinghai-Tibet Plateau, China SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB Plateau zokor (Myospalax fontanierii) is a native subterranean rodent in alpine rangeland on Qinghai-Tibet Plateau (QTP) in China, and its foraging, digging, and mounds building cause the unique disturbance pattern to alpine rangeland ecosystem. Over the past decades, the zokors have been regarded as major pests who result in the degradation of the rangeland ecosystem in the QTP and have been simply eliminated by rodenticides or traps. Understanding the function of zokors and evaluating the zokors' impacts on alpine rangeland systems should be the solid scientific basis for zokor control. In this study, we considered the average nearest neighbor indices of zokor mounds to represent the disturbance intensity of zokor to alpine rangeland and surveyed the plant species richness, diversity indices, biomass, and soil physicochemical properties in intermound areas under different zokor disturbance intensities in alpine rangeland in Tianzhu Tibet Autonomous County, located in eastern QTP. Our results indicated that 1) the plant species diversity indices were positively correlated with zokor disturbance intensity and aboveground and belowground biomasses were not significantly different under the different disturbance intensities; 2) the importance value of the forb functional group increased as the disturbance intensities increased, and the sedge functional group showed the opposite trend. The proportions of aboveground and belowground biomasses of forbs increased as the disturbance level increased; 3) there were no changes in the dominant plant species among the different disturbance intensities, but new plant species (Polygonum viviparum and Equisetum arvense) occurred in the plots with high disturbance intensities; 4) a significant positive correlation was observed between soil moisture in the 0-20 cm layer and disturbance intensity, while soil temperature exhibited a significantly negative relationship with the disturbance intensity; however, no differences in soil chemical properties were observed; and 5) redundancy analysis identified that mound building changed soil physical properties, especially soil moisture, in intermound areas, which influenced the plant community structure. In conclusion, the plateau zokor in our study area increased plant species diversity and did not decrease plant biomass, which is beneficial for alpine rangeland systems. We suggest that rangeland managers should consider the multiple functions of zokors to an alpine rangeland ecosystem instead of simply eliminating them. (C) 2020 The Society for Range Management. Published by Elsevier Inc. All rights reserved. C1 [Chu, Bin; Ye, Guohui; Zhou, Fufei; Zhang, Feiyu; Zhou, Jianwei; Hua, Limin] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Peoples R China. [Yang, Siwei] Inst Anim & Vet Sci, Bijie 551700, Peoples R China. RP Hua, LM (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Peoples R China. EM hua-lm@263.net TC 6 Z9 7 PD JUL PY 2020 VL 73 IS 4 BP 520 EP 530 DI 10.1016/j.rama.2020.02.004 UT WOS:000547491400007 DA 2023-03-23 ER PT J AU Liu, M Zhang, ZC Sun, J Li, YR Liu, Y Berihun, ML Xu, M Tsunekawa, A Chen, YJ AF Liu, Miao Zhang, Zhenchao Sun, Jian Li, Yurui Liu, Yu Berihun, Mulatu Liyew Xu, Ming Tsunekawa, Atsushi Chen, Youjun TI Restoration efficiency of short-term grazing exclusion is the highest at the stage shifting from light to moderate degradation at Zoige, Tibetan Plateau SO ECOLOGICAL INDICATORS DT Article AB Grassland degradation has profound negative impacts on ecological functions, local economic development, and social stability. Although there are many studies on the alpine grassland degradation in the Tibetan Plateau, the variation in the response of alpine meadows to degradation and restoration processes, and the underlying mechanisms remain poorly understood. To explore these issues, we selected nine grassland degradation levels along an increasing gradient at Zoige in the Tibetan Plateau, and collected vegetation and soil samples in August 2017 and 2018 to assess the state of the grassland before and after grazing exclusion (GE), respectively. The results showed that above-ground biomass (AGB), below-ground biomass (BGB), Shannon-Wiener index, soil water content (SWC), soil organic carbon (SOC), total nitrogen (STN), and total phosphorus decreased gradually with severe degrees of degradation, whereas soil bulk density and pH increased. SWC in the topsoil presented the sharpest change in slope along the degradation gradient, indicating that SWC was a sensitive indicator of alpine meadow degradation in this area. One-year GE evidently increased SWC, SOC, STN, AGB, and BGB in lightly and moderately degraded grasslands. The restoration efficiency of GE first increased and then decreased along the degradation gradient, with the turning point appearing at the third or fourth degradation level. Based on these results, we can conclude that short-term GE is an effective method for grassland restoration in this humid area, and should be performed at the shift from light to moderate degradation stages when the efficiency of recovery is the highest. These findings could facilitate a better approach for the restoration of degraded alpine meadow ecosystems. C1 [Liu, Miao; Zhang, Zhenchao; Sun, Jian; Li, Yurui; Liu, Yu; Xu, Ming] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Liu, Miao; Tsunekawa, Atsushi] Tottori Univ Tottori, Arid Land Res Ctr, Tottori 6800001, Japan. [Zhang, Zhenchao] Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing 100083, Peoples R China. [Berihun, Mulatu Liyew] Tottori Univ, United Grad Sch Agr Sci, Tottori 6808553, Japan. [Berihun, Mulatu Liyew] Bahir Dar Univ, Bahir Dar Inst Technol, Fac Civil & Water Resource Engn, POB 26, Bahir Dar, Ethiopia. [Chen, Youjun] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. RP Sun, J; Xu, M (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. EM liumiao@igsnrr.ac.cn; sunjian@igsnrr.ac.cn; liumiao@igsnrr.ac.cn; mingxu@igsnrr.ac.cn; tsunekawa@tottori-u.ac.jp TC 16 Z9 20 PD JUL PY 2020 VL 114 AR 106323 DI 10.1016/j.ecolind.2020.106323 UT WOS:000559966500007 DA 2023-03-23 ER PT J AU Luo, JF Ma, L Li, GJ Deng, DZ Chen, DC Zhang, L Zhu, XW Zhou, JX AF Luo, Jiufu Ma, Li Li, Guijing Deng, Dongzhou Chen, Dechao Zhang, Li Zhu, Xinwei Zhou, Jinxing TI The effects of land degradation on plant community assembly: Implications for the restoration of the Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Understanding how biotic and abiotic filters drive plant distributions is critical for informing restoration efforts of degraded lands. However, it remains unclear whether or not it is possible to develop efficient restoration strategies that are based on field investigations? Here, we conducted a field-based investigation along a land degradation gradient on the Tibetan Plateau. Along this gradient, we compared species composition, Pianka's niche overlap, and total aboveground biomass among grasses, sedges, legumes, and forbs. We also used Faith's (1992) phylogenetic diversity index (PD) and the net relatedness index (NRI) to measure community phylogenetic patterns. To understand the effects of abiotic filtering, we measured soil pH, moisture, electrical conductivity, total soil organic carbon, microbial biomass carbon, and microbial biomass nitrogen. Our results show that grasses replaced sedges and mesoxerophytes replaced mesohydrophytes with increasing land degradation. We also found that niche overlap declined with increasing degradation intensity. Furthermore, grass biomass increased, while sedges and legumes decreased, and forb biomass showed a hump-shaped relationship with degradation intensity. In addition, the communities transitioned from a clustered to a more random phylogenetic pattern. Soil conditions changed from acidic to alkaline and from fertile to harsh (p < .05). High niche overlap indicates a high biotic filtering at lightly degraded land where abiotic filtering is less stressful. However, when degradation is intense, abiotic filtering is apparent, as indicated by low levels of niche overlap. Overall, we suggest that distantly related, arid tolerant and hardy plants, and soil reclamation should be considered in degraded alpine lands restoration. C1 [Luo, Jiufu; Ma, Li; Li, Guijing; Zhou, Jinxing] Beijing Forestry Univ, Key Lab State Forestry Adm Soil & Water Conservat, Beijing 100083, Peoples R China. [Luo, Jiufu; Li, Guijing; Zhou, Jinxing] Beijing Forestry Univ, Jianshui Res Field Stn, Beijing, Peoples R China. [Deng, Dongzhou; Chen, Dechao] Sichuan Acad Forestry Sci, Chengdu, Peoples R China. [Zhang, Li; Zhu, Xinwei] Aba Prefecture Inst Forestry & Grassland Sci & Te, Wenchuan, Peoples R China. RP Zhou, JX (通讯作者)，Beijing Forestry Univ, Key Lab State Forestry Adm Soil & Water Conservat, Beijing 100083, Peoples R China. EM zjx001@bjfu.edu.cn TC 3 Z9 3 PD DEC PY 2020 VL 31 IS 18 BP 2819 EP 2829 DI 10.1002/ldr.3613 EA JUL 2020 UT WOS:000544420800001 DA 2023-03-23 ER PT J AU Ma, L Wang, Q Shen, ST Li, FC Li, L AF Ma, Li Wang, Qing Shen, Songtao Li, Fucheng Li, Li TI Heterogeneity of soil structure and fertility during desertification of alpine grassland in northwest Sichuan SO ECOSPHERE DT Article AB The variations of soil structure and soil physical-chemical properties in the process of alpine grassland desertification were revealed, and the indicators of grassland desertification were put forward in order to deepen the understanding of the law of degradation succession and development of alpine grassland. It was used to provide scientific basis for ecological restoration and improvement of ecological service function of alpine grassland. With severe desertification alpine grassland as the core in the Hongyuan County, Tibetan Qiang Autonomous Prefecture of Ngawa, Sichuan Province, China, along both the directions of wetland and arid grassland, the heterogeneity of soil structure and soil fertility in both directions was studied by the analysis of the mean weight diameter (MWD), geometric mean diameter (GMD), >0.25 mm aggregate content (R-0.25), fractal dimension (D), soil bulk density, soil moisture content, and soil nutrients. Our results showed that MWD, GMD, andR(0.25)all gradually increased, but theDdecreased with the reduction in the degree of desertification in the arid grassland and wetland, resulting in the strong stability of soil structure. The decreasing rate of theDin the direction of arid grassland was faster than that of wetland. Therefore, soil structure stability and erosion resistance in the direction of arid grassland were stronger than that of wetland soil; theDhad different response to aggregates with different particle sizes. The aggregate less than 0.25 mm (r = 0.981,P < 0.01) and 1-2 mm (r = -0.79,P < 0.01) had the largest responses in the direction of the arid grassland and wetland, respectively; the aggregate more than 1 mm and 1-2 mm can be used as indicators to evaluate desertification of the soil in the direction of the arid grassland and wetland, respectively. The higher the content of the indicating aggregates, the weaker the degree of the desertification. C1 [Ma, Li; Wang, Qing; Shen, Songtao; Li, Fucheng; Li, Li] Southwest Univ Sci & Technol, Sch Environm & Resource, Mianyang 621010, Sichuan, Peoples R China. [Ma, Li] Mianyang Normal Univ, Sch Resources & Environm Engn, Mianyang 621006, Sichuan, Peoples R China. RP Wang, Q (通讯作者)，Southwest Univ Sci & Technol, Sch Environm & Resource, Mianyang 621010, Sichuan, Peoples R China. EM qingw@inde.ac.cn TC 3 Z9 5 PD JUL PY 2020 VL 11 IS 7 AR e03161 DI 10.1002/ecs2.3161 UT WOS:000567408500012 DA 2023-03-23 ER PT J AU Zhu, XC Shao, MG Tang, XZ Liang, Y AF Zhu, Xuchao Shao, Mingan Tang, Xinzhai Liang, Yin TI Spatiotemporal variation and simulation of vegetation coverage in a typical degraded alpine meadow on the Tibetan Plateau SO CATENA DT Article AB The Qinghai-Tibetan Plateau is sensitive to global climate change and its vegetation is an important indicator of the change. Analyses of the mesoscale spatial variation of vegetation and its spatiotemporal influencing factors in alpine meadows are important for the management and model simulation of degraded meadows. We extracted data for vegetation coverage (VC) from digital photographs of a typically degraded alpine meadow for 22 occasions at 113 locations in a study plot. The spatial and temporal distribution, variability and influencing factors of VC were analyzed using classical statistics, geostatistics, temporal stability and correlation analysis. A first pedotransfer function was built for simulating temporal variation of VC. Average VC was 19.7 and 40.5% in the 2015 and 2016 growing seasons, respectively, and the classical and geostatistical parameters indicated moderate variability and a strong spatial dependence of the VC in the study plot. VC was correlated strongly negatively with soil bulk density and pH and strongly positively with soil organic-carbon density and total nitrogen and total potassium contents. VC was sinusoidally distributed in the 2015 growing season, which was mainly affected by rainfall-induced soil moisture condition, and was parabolically distributed in the 2016 growing season, which was mainly affected by temperature-dominated vegetation phenology. The mean coefficients of variation (CVs) of VC temporal variation in the 2015 and 2016 growing seasons were 39.8 and 36.5%, respectively, which were higher than the CVs (28.0 and 19.1%) for VC spatial variation, indicating that climate affected VC more than soil and topographical properties. The simulation of a pedotransfer function established by temporal variables i.e. 30 cm-depth soil-water content, air temperature and pressure was highly accurate and accounted for > 60% of the temporal variability of VC. These results provide basic data and recommendations for the mesoscale simulation of vegetation in alpine meadows and a scientific basis for the management of degraded meadows. C1 [Zhu, Xuchao; Liang, Yin] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, 71 Beijing East Rd, Nanjing 210008, Peoples R China. [Shao, Mingan; Tang, Xinzhai] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Shao, Mingan] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. RP Liang, Y (通讯作者)，Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, 71 Beijing East Rd, Nanjing 210008, Peoples R China. EM yliang@issas.ac.cn TC 10 Z9 10 PD JUL PY 2020 VL 190 AR 104551 DI 10.1016/j.catena.2020.104551 UT WOS:000525324600035 DA 2023-03-23 ER PT J AU Pan, T Hou, S Liu, YJ Tan, QH Liu, YH Gao, XF AF Pan, Tao Hou, Shuai Liu, Yujie Tan, Qinghua Liu, Yanhua Gao, Xiaofei TI In fluence of degradation on soil water availability in an alpine swamp meadow on the eastern edge of the Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Degraded ecosystems refer to systems that deviate from their natural state as a result of natural or anthropogenic disturbances. Alpine swamp meadows on the eastern edge of the Tibetan Plateau have dramatically degraded owing to climate change, overgrazing, and rodents. Understanding the influence of meadow degradation on soil water availability is essential for the development of hydrological models and alpine swamp meadows restoration, which has been poorly explored in the eastern Tibetan Plateau. In this study, we analyzed how degradation affects variation in soil water availability with a series of parameters derived from soil moisture content and soil water retention curves. Our results showed that (1) soil moisture content consistently decreased with degradation and increased with soil depth; (2) soil water retention curves decreased with increasing degradation due to coarser soils and organic matter loss. Field water capacity and the permanent wilting point decreased, whereas the air entry value increased with the severity of degradation; and (3) soil water availability, as represented by soil water potential, available soil water content and fraction was less responsive to degradation than individual soil moisture content or soil water retention curves, which showed similar decreasing trends. However, soil water potential, available soil water content and fraction under moderate and severe degradation were relatively lower than those under light degradation, especially in deep soil layers (>20 cm). Thus, swamp meadow degradation negatively influences soil water availability, which might impede water absorption by deeply rooted species, thereby inducing soil-water stress and possibly increasing drought vulnerability. (C) 2020 Elsevier B.V. All rights reserved. C1 [Pan, Tao; Hou, Shuai; Liu, Yujie; Tan, Qinghua; Liu, Yanhua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Hou, Shuai] Chinese Acad Agr Sci, Inst Crop Sci, Beijing 100081, Peoples R China. [Hou, Shuai] Minist Agr & Rural Affairs, Key Lab Crop Physiol & Ecol, Beijing 100081, Peoples R China. [Gao, Xiaofei] Beijing Normal Univ, Fac Geog Sci, Beijing 100088, Peoples R China. RP Liu, YJ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM liuyujie@igsnrr.ac.cn TC 13 Z9 16 PD JUN 20 PY 2020 VL 722 AR 137677 DI 10.1016/j.scitotenv.2020.137677 UT WOS:000535472600017 DA 2023-03-23 ER PT J AU Fan, QS Wanapat, M Hou, FJ AF Fan, Qingshan Wanapat, Metha Hou, Fujiang TI Chemical Composition of Milk and Rumen Microbiome Diversity of Yak, Impacting by Herbage Grown at Different Phenological Periods on the Qinghai-Tibet Plateau SO ANIMALS DT Article AB Simple Summary Native values of herbage grown at different phenological periods and rumen diversity of microbial population would impact rumen fermentation end-products and milk compositions of yaks (Bos grunniens). The research was conducted in 12 female yaks grazing on the Qinghai-Tibet Plateau (QTP). The results revealed that the phenological periods (VS: Vegetative stage, May; BS: Bloom stage, August; SS: Senescent stage, December) significantly influenced the nutritive values of herbages, microbial diversity and, as a consequence affected on the yak milk yield and compositions. We concluded that the observed differences resulted from the combined effects of phenological periods, herbage composition, and herbage availability. The findings of this study were of great value and useful for current understandings and onwards to conduct further research and for possible practical implementation for the yak cows grazing on QTP. To estimate how native herbage of three different phenological periods modify rumen performance and milk quality of yak grazing alpine meadow. In this study, milk composition and the diversity of the rumen microbial community were measured in 12 full-grazing female yaks on the Qinghai-Tibet Plateau (QTP). The nutrient composition of three phenological periods was determined: Vegetative stage (VS), bloom stage (BS), and senescent stage (SS). High-throughput sequencing of the bacterial 16S rRNA gene was used. The results showed that crude protein (CP) content of herbage in BS was higher than that in vs. and SS (p< 0.05), and neutral detergent fiber (NDF) content of herbage in SS was higher than that in vs. and BS (p< 0.05). Milk solids and fat contents were higher in the vs. and SS than in BS (p< 0.05). However, milk protein content was higher for the vs. and BS than those for SS (p< 0.05). The total volatile fatty acid (VFA), acetate, and propionate concentrations were higher in vs. and BS than in SS (p< 0.05). The community richness estimates (Chao1 estimator) of vs. were higher than that in BS and the SS (p< 0.05). The diversity indices (Shannon index) of the BS were higher than that vs. and the SS (p< 0.05). Spearman correlation analysis between the milk composition, ruminal fermentation parameters, and the relative abundances of the rumen bacteria showed that milk protein content, total VFA, acetate, and propionate concentrations were positively correlated with the relative abundances of the generaDesulfovibrio,Prevotella_1, andButyrivibrio_2and was negatively correlated withOlsenella,Ruminococcaceae_UCG.010, andRikenellaceae_RC9_gut_groupabundances. Collectively, the results revealed that there were significant differences in nutrient composition of herbage, chemical composition of yak milk, and microbial diversity in rumen at different phenological stages. The correlations between ruminal fermentation parameters, chemical constituents of yak milk, and some genera of ruminal bacteria might be indicative that the ruminal fermentation parameters and chemical constituents of yak milk are strongly influenced by the rumen bacterial community composition. C1 [Fan, Qingshan; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock,Minist Agr & Rural Af, Lanzhou 730020, Gansu, Peoples R China. [Wanapat, Metha] Khon Kaen Univ, Fac Agr, Trop Feed Resources Res & Dev Ctr TROFREC, Dept Anim Sci, Khon Kaen 40002, Thailand. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock,Minist Agr & Rural Af, Lanzhou 730020, Gansu, Peoples R China. EM Fanqsh18@lzu.edu.cn; metha@kku.ac.th; cyhoufj@lzu.edu.cn TC 18 Z9 19 PD JUN PY 2020 VL 10 IS 6 AR 1030 DI 10.3390/ani10061030 UT WOS:000553966700001 DA 2023-03-23 ER PT J AU Li, D Luo, HY Hu, TS Shao, DG Cui, YL Khan, S Luo, YF AF Li, Dan Luo, Hongying Hu, Tiesong Shao, Dongguo Cui, Yuanlai Khan, Shahbaz Luo, Yufeng TI Identification of the Roles of Climate Factors, Engineering Construction, and Agricultural Practices in Vegetation Dynamics in the Lhasa River Basin, Tibetan Plateau SO REMOTE SENSING DT Article AB Understanding vegetation dynamics is necessary to address potential ecological threats and develop sustainable ecosystem management at high altitudes. In this study, we revealed the spatiotemporal characteristics of vegetation growth in the Lhasa River Basin using net primary productivity (NPP) and normalized difference vegetation index (NDVI) during the period of 2000-2005. The roles of climatic factors and specific anthropogenic activities in vegetation dynamics were also identified, including positive or negative effects and the degree of impact. The results indicated that the interannual series of NPP and NDVI in the whole basin both had a continuous increasing trend from 102 to 128 gC m(-2) yr(-1) and from 0.417 to 0.489 (p < 0.05), respectively. The strongest advanced trends (>2 gC m(-2) yr(-1) or >0.005 yr(-1)) were detected in mainly the southeastern and northeastern regions. Vegetation dynamics were not detected in 10% of the basin. Only 20% of vegetation dynamics were driven by climatic conditions, and precipitation was the controlling climatic factor determining vegetation growth. Accordingly, anthropogenic activities made a great difference in vegetation coverage, accounting for about 70%. The construction of urbanization and reservoir led to vegetation degradation, but the farmland practices contributed the vegetation growth. Reservoir construction had an adverse impact on vegetation within 6 km of the river, and the direct damage to vegetation was within 1 km. The impacts of urbanization were more serious than that of reservoir construction. Urban sprawl had an adverse impact on vegetation within a 6 km distance from the surrounding river and resulted in the degradation of vegetation, especially within a 3 km range. Intensive fertilization and guaranteed irrigation improved the cropland ecosystem conditions, creating a favorable effect on the accumulation of crop organic matter in a range of 5 km, with an NPP trend value of 1.2 gC m(-2) yr(-1). The highly intensive grazing activity forced ecological environmental pressures such that the correlation between livestock numbers and vegetation growth trend was significantly linear negative. C1 [Li, Dan; Hu, Tiesong; Shao, Dongguo; Cui, Yuanlai; Khan, Shahbaz; Luo, Yufeng] Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan 430072, Peoples R China. [Luo, Hongying; Luo, Yufeng] Tibet Agr & Anim Husb Coll, Sch Water Resources & Civil Engn, Nyingchi 860000, Peoples R China. [Khan, Shahbaz] United Nations Educ Sci & Cultural Org, Reg Sci Bur Asia & Pacific, Dki Jakarta 12110, Indonesia. RP Luo, YF (通讯作者)，Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan 430072, Peoples R China.; Luo, YF (通讯作者)，Tibet Agr & Anim Husb Coll, Sch Water Resources & Civil Engn, Nyingchi 860000, Peoples R China. EM lidann@whu.edu.cn; lhy@xza.edu.cn; tshu@whu.edu.cn; dgshao@whu.edu.cn; YLCui@whu.edu.cn; s.khan@unesco.org; yfluo@whu.edu.cn TC 9 Z9 10 PD JUN PY 2020 VL 12 IS 11 AR 1883 DI 10.3390/rs12111883 UT WOS:000543397000188 DA 2023-03-23 ER PT J AU Liu, M Zhang, ZC Sun, J Wang, Y Wang, JN Tsunekawa, A Yibeltal, M Xu, M Chen, YJ AF Liu, Miao Zhang, Zhenchao Sun, Jian Wang, Yi Wang, Jinniu Tsunekawa, Atsushi Yibeltal, Mesenbet Xu, Ming Chen, Youjun TI One-year grazing exclusion remarkably restores degraded alpine meadow at Zoige, eastern Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Understanding the influences of grazing exclusion (GE) on soil properties and vegetation characteristics is essential for the assessment of grassland restoration. The objectives of this study are exploring the efficiency of short-term GE in restoring alpine meadow in the Zoige region, eastern Tibetan Plateau, with high rainfall amount. We conducted sampling surveys before and after one-year GE in alpine meadows with seven sequent degraded degrees. The results showed that one-year GE significantly increased soil organic carbon (SOC), soil total nitrogen (STN), soil water content (SWC), and plant biomass, while decreased soil bulk density (SBD) regardless of the degradation degree. These findings suggest that short-term GE may be an effective way to restore degraded alpine meadow. Aboveground and belowground biomass was significantly positively associated with SWC, SOC, STN, soil total phosphorus, and soil available nitrogen, but presented negative relationship with SBD. This shows the complicated interaction between vegetation and soil physiochemical properties that regulates the grassland recovery process. The degraded alpine meadow in this rainfall-rich region could rapidly recover once grazing disturbance was excluded. This study can provide technical support for restoration and sustainable management of alpine meadows on the Tibetan Plateau. (C) 2020 The Authors. Published by Elsevier B.V. C1 [Liu, Miao; Zhang, Zhenchao; Sun, Jian; Wang, Yi; Xu, Ming] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. [Liu, Miao; Tsunekawa, Atsushi] Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. [Zhang, Zhenchao] Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing 100083, Peoples R China. [Wang, Jinniu] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Yibeltal, Mesenbet] Tottori Univ, United Grad Sch Agr Sci, 1390 Hamasaka, Tottori 6808553, Japan. [Yibeltal, Mesenbet] Bahir Dar Univ, Fac Civil & Water Resource Engn, Bahir Dar Inst Technol, Bahir Dar, Ethiopia. [Xu, Ming] Rutgers State Univ, Sch Environm & Biol Sci, Dept Ecol Evolut & Nat Resources, New Brunswick, NJ 08901 USA. [Chen, Youjun] Southwest Univ Nationalities, Chengdu 610041, Peoples R China. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. EM liumiao@igsnrr.ac.cn; zhenchaozhang0626@163.com; sunjian@igsnrr.ac.cn; mrwy201314@163.com; wangjn@cib.ac.cn; tsunekawa@tottori-u.ac.jp; mesyibseb@yahoo.com; mingxu@igsnrr.ac.cn; Chenyoujun2005@163.com TC 16 Z9 18 PD JUN PY 2020 VL 22 AR e00951 DI 10.1016/j.gecco.2020.e00951 UT WOS:000575093200035 DA 2023-03-23 ER PT J AU Qian, K Yuan, QZ Han, JC Leng, R Wang, YS Zhu, KH Lin, S Ren, P AF Qian, Kuang Yuan Quan-zhi Han Ji-chong Leng Rong Wang Yu-shuang Zhu Ke-hong Lin Shuo Ren Ping TI A remote sensing monitoring method for alpine grasslands desertification in the eastern Qinghai-Tibetan Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Alpine grassland is the typical vegetation in the eastern Qinghai-Tibetan Plateau, which has important ecological service functions, and also supports the development of alpine stock farming. In recent years, under both the natural and human disturbance, alpine grasslands in this area have appeared to different degrees of desertification. A diagnosis of the desertification degree serves as the basis for grassland ecological restoration. This study constructs a comprehensive index based on remote sensing called alpine grassland desertification index (AGDI) to monitor the areas and degree of desertification. The most relevant indicators of desertification, namely, vegetation fraction, aboveground biomass, soil moisture, and land surface temperature, were selected to establish AGDI. The geographical detector is used to reselect and assess these indicators. The results show that the overall verification accuracy of AGDI is 82.05%. In particular, the accuracy of identifying severe desertification is the highest. Our study confirms that the desertification of alpine grasslands in the eastern Qinghai-Tibetan Plateau is characterized by fragmentation. Thus, Landsat-8 OLI data with a spatial resolution of 30 m is more suitable than MODIS data for alpine grasslands desertification monitoring. The research results can provide a methodological reference for monitoring desertification of alpine grasslands and other grassland regions in the world. C1 [Qian, Kuang; Yuan Quan-zhi; Leng Rong; Wang Yu-shuang; Ren Ping] Sichuan Normal Univ, Key Lab Land Resources Evaluat & Monitoring South, Minist Educ, Chengdu 610068, Peoples R China. [Qian, Kuang; Yuan Quan-zhi; Leng Rong; Wang Yu-shuang; Ren Ping] Sichuan Normal Univ, Inst Geog & Resources Sci, Chengdu 610068, Peoples R China. [Han Ji-chong] Beijing Normal Univ, Key Lab Environm Change & Nat Disaster, Fac Geog Sci,Acad Disaster Reduct & Emergency Man, MOE,State Key Lab Earth Surface Proc & Resources, Beijing 100875, Peoples R China. [Zhu Ke-hong] Tsinghua Univ, Dept Engn Phys, Beijing 100084, Peoples R China. [Lin Shuo] Sichuan Agr Univ, Coll Resources, Chengdu 611130, Peoples R China. RP Yuan, QZ (通讯作者)，Sichuan Normal Univ, Key Lab Land Resources Evaluat & Monitoring South, Minist Educ, Chengdu 610068, Peoples R China.; Yuan, QZ (通讯作者)，Sichuan Normal Univ, Inst Geog & Resources Sci, Chengdu 610068, Peoples R China. EM 20171103004@stu.sicnu.edu.cn; yuanqz@sienu.edu.en; 201921051199@mail.bnu.edu.cn; 20181101005@stu.sienu.edu; 20181101002@stu.sienu.edu.en; zhukehong@nuctech.com; 1144250667@qq.com; pren121680@126.com TC 10 Z9 11 PD JUN PY 2020 VL 17 IS 6 BP 1423 EP 1437 DI 10.1007/s11629-020-5986-6 UT WOS:000538038700011 DA 2023-03-23 ER PT J AU Shi, XN Zhang, F Wang, L Jagirani, MD Zeng, C Xiao, X Wang, GX AF Shi, Xiaonan Zhang, Fan Wang, Li Jagirani, Muhammad Dodo Zeng, Chen Xiao, Xiong Wang, Guanxing TI Experimental study on the effects of multiple factors on spring meltwater erosion on an alpine meadow slope SO INTERNATIONAL SOIL AND WATER CONSERVATION RESEARCH DT Article AB Meadow degradation provides a major indication of increased soil erosion in alpine regions. Serious soil erosion is observed during the spring in particular because soil thawing coincides with the period of snowmelt and the meadow coverage is very low at this time. Studies relating to soil erosion caused by spring meltwater are, however, limited and controversial. Therefore, a field experimental study was conducted in a typical meadow in the Binggou watershed on the northern edge of the Tibetan Plateau to assess the impact of multiple factors on spring meltwater erosion on an alpine meadow slope. The multiple factors included three flow rates (1, 2, and 3 L/min), four slope gradients (10 degrees, 15 degrees, 20 degrees, and 25 degrees), and three underlying surface conditions (meadow, disturbed meadow, and alluvial soil). An equal volume of concentrated meltwater flow was used in all experiments. The results showed that rapid melting at a high flow rate could accelerate soil erosion; as the flow rate increased from 1 to 3 L/min, the total surface runoff increased by a factor of 0.7 and the total sediment yield increased by more than 6-fold. The influence of the slope gradient on the amount of runoff was positively linear and the influence was relatively low; when the slope increased from 10 degrees to 25 degrees, the total runoff only increased by 16%. However, the slope gradient had a strong impact on soil erosion. The total sediment yield doubled when the slope increased from 10 degrees to 20 degrees and then slightly decreased at 25 degrees. The meadow could effectively reduce soil erosion, although when the meadow was disturbed, the total runoff increased by 60% and the sediment yield by a factor of 1.5. The total runoff from the alluvial soil doubled in comparison to the meadow, while the sediment yield increased nearly 7-fold. The findings of this study could be helpful to understand the characteristics and impact of multiple controlling factors of spring meltwater erosion. It also aims to provide a scientific basis for an improved management of alpine meadows as well as water and soil conservation activities in high-altitude cold regions. (c) 2020 International Research and Training Center on Erosion and Sedimentation and China Water and Power Press. Production and Hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). C1 [Shi, Xiaonan; Zhang, Fan; Wang, Li; Jagirani, Muhammad Dodo; Zeng, Chen; Xiao, Xiong; Wang, Guanxing] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100101, Peoples R China. [Shi, Xiaonan; Zhang, Fan] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhang, Fan; Zeng, Chen; Xiao, Xiong] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Shi, XN (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100101, Peoples R China. EM shixiaonan@itpcas.ac.cn TC 4 Z9 5 PD JUN PY 2020 VL 8 IS 2 BP 116 EP 123 DI 10.1016/j.iswcr.2020.02.001 UT WOS:000540327800002 DA 2023-03-23 ER PT J AU Tian, LH Bai, YF Wang, WW Qu, GP Deng, ZH Li, RC Zhao, JX AF Tian, Lihua Bai, Yanfu Wang, Weiwei Qu, Guangpeng Deng, Zhaoheng Li, Ruicheng Zhao, Jingxue TI Warm- and cold- season grazing affect plant diversity and soil carbon and nitrogen sequestration differently in Tibetan alpine swamp meadows SO PLANT AND SOIL DT Article AB Background and aims Seasonal grazing is a traditional grassland management practice in alpine swamp meadows on the Tibetan Plateau, but little information is available on the interactions between plant diversity and soil carbon and nitrogen sequestration in warm- and cold- season grazed alpine swamp meadows. Methods A multisite survey was conducted to investigate the plant characteristics and soil properties of Tibetan alpine swamp meadows under warm-season grazing (WG) and cold-season grazing (CG). Results Our study showed that plant biomass, litter mass, soil water content (SW), soil available nitrogen, soil microbial biomass carbon and nitrogen were significantly lower in the WG meadows than in the CG meadows (P < 0.05). However, plant diversity, species richness and the evenness index tended to increase in the WG meadows. Soil C and N storage were significantly lower in the WG meadows than in the CG meadows (P < 0.01). Grazing-induced changes in SW, plant diversity, plant biomass and litter mass were the major factors resulting in the decrease in soil C and N storage. Conclusions Our results indicate that warm-season grazing is beneficial for species diversity conservation, whereas cold-season grazing is suitable for soil C and N sequestration in alpine swamp meadows. Grazing-induced changes in litter mass greatly contributed to variations in plant diversity and soil C and N storage. In view of the accelerated vegetation and soil degradation in alpine grasslands, periodic warm- and cold-season grazing strategies should be considered to maintain alpine swamp meadow sustainability. C1 [Tian, Lihua] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. [Bai, Yanfu; Wang, Weiwei; Zhao, Jingxue] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Inst Innovat Ecol, Lanzhou 730000, Peoples R China. [Bai, Yanfu; Wang, Weiwei; Zhao, Jingxue] Lanzhou Univ, Coll Life Sci, Lanzhou 730000, Peoples R China. [Qu, Guangpeng; Zhao, Jingxue] State Key Lab Hulless Barley & Yak Germplasm Reso, Lhasa 850002, Peoples R China. [Deng, Zhaoheng] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Li, Ruicheng; Zhao, Jingxue] Peking Univ, Dept Ecol, Coll Urban & Environm Sci, 5 Yiheyuan Rd, Beijing 100871, Peoples R China. [Li, Ruicheng; Zhao, Jingxue] Peking Univ, Key Lab Earth Surface Proc, Minist Educ, 5 Yiheyuan Rd, Beijing 100871, Peoples R China. RP Zhao, JX (通讯作者)，Peking Univ, Dept Ecol, Coll Urban & Environm Sci, 5 Yiheyuan Rd, Beijing 100871, Peoples R China.; Zhao, JX (通讯作者)，Peking Univ, Key Lab Earth Surface Proc, Minist Educ, 5 Yiheyuan Rd, Beijing 100871, Peoples R China. EM zhaojx@pku.edu.cn TC 11 Z9 13 PD JAN PY 2021 VL 458 IS 1-2 SI SI BP 151 EP 164 DI 10.1007/s11104-020-04573-6 EA MAY 2020 UT WOS:000535869300001 DA 2023-03-23 ER PT J AU Wei, D Zhao, H Zhang, JX Qi, YH Wang, XD AF Wei, Da Zhao, Hui Zhang, Jianxin Qi, Yahui Wang, Xiaodan TI Human activities alter response of alpine grasslands on Tibetan Plateau to climate change SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB The world's largest alpine pastures are found on the Tibetan Plateau, where considerable climate changes and human impacts have been experienced. Identifying their contributions to terrestrial productivity is essential if we are to adapt to, or mitigate the effects of, climate change. In this work, we begin by showing how the current warming and wetting of the climate over the last three decades has favored plant growth, as consistently captured by satellite observations and 15 models. However, the interactions between climate factors explain less of the variation in greenness observed by satellites after the 2000s, implying non-climatic influences. Next, we show that there is a significant negative impact of livestock grazing on pasture greenness, especially in peak summer. Official statistics across 72 counties verify these negative impacts, especially in poorer pastures with a higher density of grazing livestock. The variation in grazing density has a stronger negative effect on vegetation growth during the early part of the growing season after the 2000s, as compared with that before the 2000s. We found a compensatory effect of grazing and climate on alpine grassland growth, and the grazing regulates the response of vegetation greenness to climate change by modulating the dependency of vegetation growth on temperature. Thus, we suggest there is a weakening influence of climate on the greenness of alpine pastures, largely due to a strengthening influence of management, which should be considered by both the scientific community and policymakers. C1 [Wei, Da; Zhao, Hui; Zhang, Jianxin; Qi, Yahui; Wang, Xiaodan] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Zhang, Jianxin; Qi, Yahui] Chinese Acad Sci, Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Wang, XD (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, 9,Sect 4,Renminnanlu Rd, Chengdu, Sichuan, Peoples R China. EM wxd@imde.ac.cn TC 31 Z9 34 PD MAY 15 PY 2020 VL 262 AR 110335 DI 10.1016/j.jenvman.2020.110335 UT WOS:000527016200054 DA 2023-03-23 ER PT J AU Ding, XL Chen, SY Zhang, B He, HB Filley, TR Horwath, WR AF Ding, Xueli Chen, Shengyun Zhang, Bin He, Hongbo Filley, Timothy R. Horwath, William R. TI Warming yields distinct accumulation patterns of microbial residues in dry and wet alpine grasslands on the Qinghai-Tibetan Plateau SO BIOLOGY AND FERTILITY OF SOILS DT Article AB High altitude alpine grasslands in the Qinghai-Tibetan Plateau (QTP) contain high soil organic C (SOC) stocks that are extremely vulnerable to climate warming. Microbial residues are increasingly recognized as a major source of SOC, however, how climate warming affects this component of SOC in this region remains largely unknown. In this study, we examined the response of microbial residues to a 3-year experimental warming and the degree to which they contributed to SOC storage in two Tibetan ecosystems-alpine steppe (AS) and swamp meadow (SM). The number of microbial residues was indicated by amino sugar analysis. Our results revealed that warming yielded divergent microbial residue accumulation that significantly altered their contribution to SOC storage in the two alpine grasslands. Warming increased microbial residue abundance by approximately 17.6% across 0 to 20 cm depth in SM soils, while causing a significant decline (about 6.2%) in AS soils. The higher microbial residue accumulation in SM could lessen potential positive feedbacks from climate warming, while the decrease in microbial residues in AS may indicate greater loss of microbial-derived C inputs in warmed soils. Moreover, we found that warming selectively increased fungal residues as compared with bacterial despite inconsistent responses to warming in the two grasslands. These changes were accompanied by significant shifts in fungal to bacterial residue C ratios and their contribution to SOC pool, indicating an alteration of SOC composition and stability in alpine grassland ecosystems. These findings demonstrate that a microbial-derived C feedback to climate change is ecosystem-specific that alters the direction and magnitude of the microbial community. C1 [Ding, Xueli; Zhang, Bin] Nanjing Univ Informat Sci & Technol, Sch Appl Meteorol, Nanjing 210044, Peoples R China. [Chen, Shengyun] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China. [He, Hongbo] Chinese Acad Sci, Inst Appl Ecol, Shenyang 110016, Peoples R China. [Filley, Timothy R.] Purdue Univ, Dept Earth Atmospher & Planetary Sci, W Lafayette, IN 47907 USA. [Horwath, William R.] Univ Calif Davis, Dept Land Air & Water Resources, Davis, CA 95616 USA. RP Ding, XL (通讯作者)，Nanjing Univ Informat Sci & Technol, Sch Appl Meteorol, Nanjing 210044, Peoples R China.; Horwath, WR (通讯作者)，Univ Calif Davis, Dept Land Air & Water Resources, Davis, CA 95616 USA. EM dingxueli@nuist.edu.cn; wrhorwath@ucdavis.edu TC 14 Z9 15 PD OCT PY 2020 VL 56 IS 7 BP 881 EP 892 DI 10.1007/s00374-020-01474-9 EA MAY 2020 UT WOS:000531776500002 DA 2023-03-23 ER PT J AU Dai, LC Guo, XW Ke, X Du, YG Mang, FW Cao, GM AF Dai, Licong Guo, Xiaowei Ke, Xun Du, Yangong Mang, Fawei Cao, Guangmin TI The variation in soil water retention of alpine shrub meadow under different degrees of degradation on northeastern Qinghai-Tibetan plateau SO PLANT AND SOIL DT Article AB Background and aims In recent decades, an increasing proportion of alpine shrub meadow has become severely degraded owing to the combined effects of global climate warming and rodent infestation, with significant impacts on soil water retention. The present paper investigates the patterns and controlling factors of soil water retention of alpine shrub meadow under different degrees of degradation, to help inform decisions on the management of degraded alpine shrub meadow. Methods Four degradation stages were defined: non-degradation (ND); light degradation (LD); moderate degradation (MD) and higher degradation (HD). Pearson correlation and redundancy analysis were used to examine the relationships between soil physical properties and soil hydraulic properties. Results Sand content increased while clay content decreased with increasing degree of degradation. In HD treatment, the available nitrogen and soil bulk density of surface soil layer was significantly lower than that in the other three stages, whereas the soil organic matter content and soil total porosity of surface soil layer was increased significantly, the soil compaction of 0-10 cm soil depth in HD was reduced significantly. The soil water retention of 0-60 cm soil depth first decreased and then increased with increasing degradation, with the maximum values occurring in HD, and the soil organic matter has an overwhelming effect on soil water retention than soil texture. Conclusions As the degree of degradation increased, the surface soil structure deteriorated, and available nitrogen reduced while soil organic matter increased sharply in higher degradation, which leads to the highest soil water retention in higher degradation. Our results suggested that the soil water retention in degraded alpine grassland was largely determined by soil organic matter, and the soil organic matter parameters should be incorporated in hydrological models of degraded alpine ecosystem. C1 [Dai, Licong; Guo, Xiaowei; Ke, Xun; Du, Yangong; Mang, Fawei; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810001, Qinghai, Peoples R China. [Mang, Fawei] Luoyang Normal Univ, Coll Life Sci, Luoyang 471934, Henan, Peoples R China. [Dai, Licong; Ke, Xun] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Guo, XW; Du, YG (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810001, Qinghai, Peoples R China. EM xwguo1206@163.com; ygdu@nwipb.cas.cn TC 17 Z9 17 PD JAN PY 2021 VL 458 IS 1-2 SI SI BP 231 EP 244 DI 10.1007/s11104-020-04522-3 EA MAY 2020 UT WOS:000531388900002 DA 2023-03-23 ER PT J AU Che, RX Liu, D Qin, JL Wang, F Wang, WJ Xu, ZH Li, LF Hu, JM Tahmasbian, I Cui, XY AF Che, Rongxiao Liu, Dong Qin, Jinling Wang, Fang Wang, Weijin Xu, Zhihong Li, Linfeng Hu, Jinming Tahmasbian, Iman Cui, Xiaoyong TI Increased litter input significantly changed the total and active microbial communities in degraded grassland soils SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Purpose Increasing organic matter input and phosphorus fertilization are employed extensively to restore degraded grasslands. Nevertheless, little is known about their effects on microbes, especially on active microbial populations. Therefore, this study is aimed at examining the short-term influences of litter and phosphorus addition on microbes in degraded grassland soils. Materials and methods A microcosm experiment was established using soils sampled from a heavily degraded Tibetan alpine meadow. The experiment used a two-way factorial design with grass litter and phosphorus addition as the main factors. Microbial abundance and rDNA transcriptional activity were assessed through quantitative PCR. Total and active microbial community profiles were measured using DNA- and RNA-based MiSeq sequencing, respectively. Results and discussion As shown in this study, litter addition significantly increased microbial rDNA transcriptional activity and fungal abundance, but it decreased microbial alpha-diversity. However, prokaryote abundance was unaffected by the litter addition. Total and active soil microbial community profiles and interaction patterns were also significantly altered by litter addition. The relative abundance of copiotrophic and oligotrophic microbial lineages significantly increased and decreased, respectively, in the soils with litter addition. Functional predictions suggested that litter addition might significantly increase the abundance of pathogens, as well as microbes related to nitrogen fixation, denitrification, and chitinolysis, while decreasing nitrifier abundance. In contrast, no significant effects of the phosphorus addition on soil microbes were observed. Conclusions These findings highlight the significant effects of increasing litter input on total and active soil microbial communities and suggest that microbial responses should be considered when restoring degraded grasslands by increasing organic matter input. C1 [Che, Rongxiao; Hu, Jinming] Yunnan Univ, Inst Int Rivers & Ecosecur, Yunnan Key Lab Int Rivers & Transboundary Ecosecu, Kunming 650091, Yunnan, Peoples R China. [Che, Rongxiao; Qin, Jinling; Wang, Fang; Li, Linfeng; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Che, Rongxiao; Wang, Fang; Wang, Weijin; Xu, Zhihong; Li, Linfeng] Griffith Univ, Environm Futures Res Inst, Brisbane, Qld 4111, Australia. [Liu, Dong] Yunnan Univ, State Key Lab Nat Resource Conservat & Utilizat Y, Kunming, Yunnan, Peoples R China. [Liu, Dong] Yunnan Univ, Sch Life Sci, Ctr Life Sci, Kunming, Yunnan, Peoples R China. [Tahmasbian, Iman] Charles Sturt Univ, Graham Ctr Agr Innovat, Wagga Wagga, NSW 2650, Australia. [Cui, Xiaoyong] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Cui, Xiaoyong] Chinese Acad Sci, Huairou Ecoenvironm Observ, Beijing 101408, Peoples R China. RP Cui, XY (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China.; Cui, XY (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China.; Cui, XY (通讯作者)，Chinese Acad Sci, Huairou Ecoenvironm Observ, Beijing 101408, Peoples R China. EM cuixy@ucas.ac.cn TC 12 Z9 13 PD JUL PY 2020 VL 20 IS 7 BP 2804 EP 2816 DI 10.1007/s11368-020-02619-x EA MAY 2020 UT WOS:000530168000003 DA 2023-03-23 ER PT J AU Song, MH Zhu, JF Li, YK Zhou, HK Xu, XL Cao, GM Lin, L Ouyang, H AF Song, Ming-Hua Zhu, Jue-Fei Li, Yi-Kang Zhou, Hua-Kun Xu, Xing-Liang Cao, Guang-Min Lin, Li Ouyang, Hua TI Shifts in functional compositions predict desired multifunctionality along fragmentation intensities in an alpine grassland SO ECOLOGICAL INDICATORS DT Article AB Grassland ecosystems are experiencing increasing perturbations from climate change and anthropogenic activities, which often cause vegetation fragmentation and grassland degradation. Although individual ecosystem functions have been extensively investigated in the vegetation fragmentation and grassland degradation processes, the multiple ecosystem functions are rarely evaluated. Moreover, little is known on how species richness and functional compositions are associated with individual functions, and how such functions contribute to multifunctionality during vegetation fragmentation. In this study, 14 interconnected functions were derived from the seven fragmentation intensities of grassland on the Tibetan Plateau. According to vegetation continuity, three communities (an ungrazed grasses and Kobresia humilis community, a lightly-grazed Kobresia humilis and K. pygmaea community, and a medium-grazed K. pygmaea community) were treated as the pre-patchiness stage, and four communities (a heavily-grazed cracked K. pygmaea community, an eroded K. pygmaea community, a severely eroded K. pygmaea community, and a bare black-soil crust) were treated as the vegetation patchiness stage. Multivariate diversity interaction framework was used to test the effects of species richness and functional composition on multiple ecosystem functions. Desired multifunctionality was assessed based on three relatively independent functions: aboveground biomass, belowground biomass, and soil organic carbon (SOC) storage. The threshold was identified to signify the rapid decline of the multifunctionality. Our results showed that positive effects of species richness were observed among most of the functions in pre-patchiness communities. Such effects disappeared in vegetation patchiness communities. Shifts in functional composition explained the large variations in most of the functions in the two stages. Furthermore, a trade-off in abundance between grasses and sedges contributed to the negative correlation between the aboveground and belowground biomass in the pre-patchiness stage. Consistent decreases in the abundance of functional groups led to a rapid decline of the individual functions, and, as a consequence, an abrupt decline in the multifunctionality. Our results demonstrated that managing grassland for ecosystem multifunctionality and species conservation requires a detailed understanding of the effects of the various drivers, including species richness, functional composition, grazing intensity, and climate conditions. C1 [Song, Ming-Hua; Zhu, Jue-Fei; Xu, Xing-Liang; Ouyang, Hua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, A11 Datun Rd, Beijing 100101, Peoples R China. [Zhu, Jue-Fei] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Song, Ming-Hua; Li, Yi-Kang; Zhou, Hua-Kun; Cao, Guang-Min; Lin, Li] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, 59 Xiguan Dajie, Xining 810008, Peoples R China. [Li, Yi-Kang] Chinese Acad Sci, Northwest Inst Plateau Biol, CAS Key Lab Adaptat & Evolut Plateau Biota, 59 Xiguan Dajie, Xining 810008, Peoples R China. RP Song, MH; Li, YK (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, A11 Datun Rd, Beijing 100101, Peoples R China.; Song, MH; Li, YK (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, 59 Xiguan Dajie, Xining 810008, Peoples R China. EM songmh@igsnrr.ac.cn; ykli@nwipb.cas.cn TC 10 Z9 12 PD MAY PY 2020 VL 112 AR 106095 DI 10.1016/j.ecolind.2020.106095 UT WOS:000518385800078 DA 2023-03-23 ER PT J AU Wang, YX Zhang, XL Sun, Y Chang, SH Wang, ZF Li, G Hou, FJ AF Wang, Yingxin Zhang, Xinglu Sun, Yi Chang, Shenghua Wang, Zhaofeng Li, Guang Hou, Fujiang TI Pika burrow and zokor mound density and their relationship with grazing management and sheep production in alpine meadow SO ECOSPHERE DT Article AB Plateau pikas (Ochotona curzoniae) and plateau zokors (Myospalax baileyi) occur naturally in the alpine meadow of the Qinghai-Tibet Plateau (QTP). Their feeding and burrowing activities affect plant composition and soil properties (e.g., soil carbon accumulation and soil nitrogen cycling), but research to study the complex interactions between small mammals, livestock, and habitat is currently lacking. We conducted a sheep grazing trial to determine the effect of grazing management on pika burrow and zokor mound density, and the relationships between sheep production and pika burrow and zokor mound density. The grazing management approaches were warm-season rotational grazing at 24 and 48 sheep months (SM)/ha, cold-season rotational grazing at 24 and 48 SM/ha, seasonal continuous grazing at 24 SM/ha, and whole-year continuous grazing at 48 SM/ha. The results of this study suggested that warm-season rotational grazing at low stocking rate did not significantly change both pika and zokor densities. Cold-season rotational grazing at both high and low stocking rates and seasonal continuous grazing at low stocking rate led to an increase in zokor mound density, but not pika burrow density. Whole-year continuous grazing at high stocking rate increased both pika and zokor densities. The influence of pika and zokor activities on sheep production was complex and differed between grazing management. Sheep liveweight gain peaked at moderate pika burrow and zokor mound density at low stocking rate under both warm- and cold-season rotational grazing. The threshold values of pika density were about 110 and 70 burrows per hectare in warm and cold seasons, respectively. The threshold value of zokor density was about 400 mounds per hectare in the cold season. In contrast, under high stocking rate regardless of management approach, sheep liveweight gain declined significantly as both pika burrow and zokor mound density increased. This paper provides a theoretical understanding and experimental evidence for sustainable grazing management and restoration of degraded grassland by local herders and policymakers. C1 [Wang, Yingxin; Sun, Yi; Chang, Shenghua; Wang, Zhaofeng; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. [Wang, Yingxin; Sun, Yi; Chang, Shenghua; Wang, Zhaofeng; Hou, Fujiang] Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China. [Zhang, Xinglu; Li, Guang] Gansu Agr Univ, Coll Forestry, Gansu Prov Key Lab Arid Land Crop Sci, Lanzhou 730070, Gansu, Peoples R China. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China.; Hou, FJ (通讯作者)，Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China. EM cyhoufj@lzu.edu.cn TC 13 Z9 13 PD MAY PY 2020 VL 11 IS 5 AR e03088 DI 10.1002/ecs2.3088 UT WOS:000538094900003 DA 2023-03-23 ER PT J AU Wang, YX Sun, Y Chang, SH Wang, ZF Fu, H Zhang, WG Hou, FJ AF Wang, Yingxin Sun, Yi Chang, Shenghua Wang, Zhaofeng Fu, Hua Zhang, Weiguo Hou, Fujiang TI Restoration Practices Affect Alpine Meadow Ecosystem Coupling and Functions SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB Degradation of alpine meadows on the Qinghai-Tibetan Plateau is an important issue for ecological science, policy making, and the welfare of local herders. Destruction of alpine meadows results from degeneration of vegetation and soil systems and from the mechanical decoupling of the environment, grassland, livestock, and herders and, subsequently, discordance among these subsystems. In this study, systematic integration of restoration techniques based on the grassland agroecosystems coupling theory was developed for the management and restoration of degraded alpine meadows. To test the effectiveness of these integrated restoration techniques, we conducted restoration trials that included grazing management, enclosed, fertilization, overseeding, and sward ripping by evaluating the ecosystem coupling of soil, plant and livestock, and ecosystem functions. The results of this study suggest that comprehensive restoration practices include grazing and agronomy techniques (fertilizer, overseeding, and sward ripping) that result in the greatest level of ecosystem coupling, while the single restoration practice leads to poorly coupled ecosystems. Restoration practice changes in ecosystem functionality are positively related to changes in ecosystem coupling. Our results highlight the importance of diversified restoration practices for facilitating ecological coupling and functioning in the degraded alpine meadow. The restorative scheme also bridges the gap between restoration theory and practice by providing guidelines for herders and policy makers for the urgent task of restoring degraded alpine meadows. (C) 2020 The Authors. Published by Elsevier Inc. on behalf of The Society for Range Management. C1 [Wang, Yingxin; Sun, Yi; Chang, Shenghua; Wang, Zhaofeng; Fu, Hua; Zhang, Weiguo; Hou, Fujiang] State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. [Wang, Yingxin; Sun, Yi; Chang, Shenghua; Wang, Zhaofeng; Fu, Hua; Zhang, Weiguo; Hou, Fujiang] Minist Agr & Rural Affairs, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730020, Peoples R China. [Wang, Yingxin; Sun, Yi; Chang, Shenghua; Wang, Zhaofeng; Fu, Hua; Zhang, Weiguo; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. EM cyhoufj@lzu.edu.cn TC 7 Z9 7 PD MAY PY 2020 VL 73 IS 3 BP 441 EP 451 DI 10.1016/j.rama.2020.01.004 UT WOS:000537289300012 DA 2023-03-23 ER PT J AU Yuan, ZQ Wu, QB Song, X Jiang, XJ Gao, SR Wang, QF Li, GY AF Yuan, Zi-Qiang Wu, Qing-Bai Song, Xin Jiang, Xiao-Jin Gao, Si-Ru Wang, Qing-Feng Li, Guo-Yu TI Pasture degradation impact on soil carbon and nitrogen fractions of alpine meadow in a Tibetan permafrost region SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Purpose Knowledge of the effects of pasture degradation on soil organic carbon (SOC) and nitrogen (N) fractions in permafrost soils on the Tibetan Plateau is limited. The aims of this study were (1) to evaluate the changes in SOC and N contents in density fractions under Kobresia pasture due to degradation and (2) to explore the contributions of the changes of SOC and N in density fractions to the changes of SOC and N in whole soil. Materials and methods The impact of Kobresia pasture degradation on SOC and N fractions was investigated in the permafrost region of the Tibetan Plateau. A continuously degraded pasture was identified and classified into three categories of vegetation cover according to their degrees of degradation (i.e., vegetation cover decline from 90% +/- 6.6% to 70% +/- 8.3% and 45% +/- 8.7%). The SOC and N fractions were separated by using the density separation method. Results and discussion The Kobresia pasture degradation significantly decreases SOC and N contents and stocks in soils. The SOC and N contents in the whole soil were positively correlated with the SOC and N contents in the light and heavy fractions (p < 0.001, respectively). The SOC and N contents were significantly correlated with soil pH and the contents of soil moisture, clay, silt, and sand. The ratio of SOC to total N in the whole soil was positively correlated with the ratio of SOC to N in heavy fractions (p < 0.001) rather than the ratio of SOC to N in light factions (p > 0.05). When pasture degraded from vegetation covers 90% to 45%, SOC stock at 0-40-cm soil layer decreased by 28.7% and N stock decreased by 39.2% in the whole soil; 56.6% and 47.6%, respectively, in the light fractions and 14.3% and 40.6%, respectively, in the heavy fractions. The depletion rates of N were higher than those of SOC in the heavy fractions and whole soil. At all sites, more than 80% of the SOC and N stocks were protected in heavy fractions. Conclusions These results indicate that a decoupling depletion of SOC and soil N appeared with the Kobresia pasture degradation in the permafrost region of the Tibetan Plateau. The Kobresia pasture degradation affects the SOC and N fractions differently and thus regulates soil carbon and N cycling in the permafrost soils on the Tibetan Plateau. C1 [Yuan, Zi-Qiang; Wu, Qing-Bai; Gao, Si-Ru; Wang, Qing-Feng; Li, Guo-Yu] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. [Song, Xin] Lanzhou Univ, Sch Life Sci, Inst Arid Agroecol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Jiang, Xiao-Jin] Chinese Acad Sci, CAS Key Lab Trop Forest Ecol, Xishuangbanna Trop Bot Garden, Menglun 666303, Yunnan, Peoples R China. RP Li, GY (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. EM guoyuli@lzb.ac.cn TC 7 Z9 9 PD MAY PY 2020 VL 20 IS 5 BP 2330 EP 2342 DI 10.1007/s11368-020-02596-1 UT WOS:000528598500002 DA 2023-03-23 ER PT J AU Chen, QY Niu, B Hu, YL Luo, TX Zhang, GX AF Chen, Qiuyu Niu, Bin Hu, Yilun Luo, Tianxiang Zhang, Gengxin TI Warming and increased precipitation indirectly affect the composition and turnover of labile-fraction soil organic matter by directly affecting vegetation and microorganisms SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Global warming accompanied by precipitation changes impacts soil carbon sequestration. A three-year field manipulation experiment with warming ( +2 degrees C above ambient temperature) and increased precipitation (+15% and +30% above ambient precipitation) was conducted in an alpine grassland to investigate the response of soil organic matter (SOM) to future climate change on the Qinghai-Tibet Plateau (QTP). Labile-fraction SOM (LF-SOM) fingerprints were characterized by pyrolysis-gas chromatography/tandem-mass spectrometry (PyGC-MS/MS), and organic compounds in LF-SOM were used as indicators to quantify the contributions of vegetation input and microbial degradation to LF-SOM transformation. Increased precipitation promoted LE-SOM accumulation, which were mainly due to the positive effect of increased precipitation on vegetation productivity. Plant-derived compounds in LF-SOM (including lignin, long-chain alkyl compounds, polysaccharides and phenols) were more sensitive to increasing soil moisture than microbial-derived (including short-chain alkyl compounds, N compounds and chitin) and aromatic-derived compounds (including aromatics and polyaromatics). In contrast, warming alone intensified the effect of drought on the alpine grassland, which had negative effects on both vegetation and microorganisms and reduced LF-SOM. Warming plus increased precipitation not only alleviated the water loss caused by warming but also increased soil temperature, which was more favorable for the growth of microorganisms. This was reflected in the increase in microbial-derived compounds in LF-SOM with increasing soil temperature, which contributed to LF-SOM degradation. Aromatic-derived compounds, as refractory compounds in soil, showed no significant response to either warming or increased precipitation treatments. Acidobacteria (approximately 25%) and Actinobacteria (approximately 20%), as the dominant soil bacterial communities in the alpine grassland, were significantly correlated with plant-derived compounds. At the same time, there were significant correlations between Proteobacteria and microbial-derived compounds, as well as between Firmicutes and aromatic-derived compounds (relative abundance). Under future climate change, microbial activity will increase as temperature increases, which will promote Li-SOM degradation only if precipitation also increases. (C) 2020 Elsevier B.V. All rights reserved. C1 [Chen, Qiuyu; Niu, Bin; Hu, Yilun; Luo, Tianxiang; Zhang, Gengxin] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Niu, Bin; Hu, Yilun] Univ Chinese Acad Sci, Beijing 10049, Peoples R China. [Chen, Qiuyu; Zhang, Gengxin] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Key Lab Alpine Ecol LAE, Beijing, Peoples R China. [Chen, Qiuyu; Zhang, Gengxin] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. RP Zhang, GX (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China.; Zhang, GX (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Key Lab Alpine Ecol LAE, Beijing, Peoples R China.; Zhang, GX (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. EM zhangg@itpcas.ac.cn TC 36 Z9 41 PD APR 20 PY 2020 VL 714 AR 136787 DI 10.1016/j.scitotenv.2020.136787 UT WOS:000517760200149 DA 2023-03-23 ER PT J AU Yan, L Li, Y Wang, L Zhang, XD Wang, JZ Wu, HD Yan, ZQ Zhang, KR Kang, XM AF Yan, Liang Li, Yong Wang, Li Zhang, Xiaodong Wang, Jinzhi Wu, Haidong Yan, Zhongqing Zhang, Kerou Kang, Xiaoming TI Grazing significantly increases root shoot ratio but decreases soil organic carbon in Qinghai-Tibetan Plateau grasslands: A hierarchical meta-analysis SO LAND DEGRADATION & DEVELOPMENT DT Article AB The Qinghai-Tibetan Plateau (QTP) is the most expansive area of alpine grasslands worldwide, which have been grazed for thousands of years. Distinct environmental conditions render QTP grasslands vulnerable to disturbances. Intensified grazing in the area has led to its degradation in recent decades. However, the effects of grazing on grassland production, soil carbon, and nitrogen contents, their relationships and the factors influencing the grasslands of QTP have yet to be determined. In this study, we evaluated the effect of grazing by using a hierarchical meta-analysis, and explored relation of response variables by structural equation modeling. In all, grazing significantly decreased the aboveground biomass (-38%), total biomass (TB) (-14%), litter (-63%), soil organic carbon (SOC) (-20%), and total nitrogen (TN) (-15%). The root shoot ratio was increased (75%). Grazing intensity exerted significant effects, and mean annual temperature and altitude influenced the responses to a certain degree. Specifically, the response of the root shoot ratio, which can affect the responses of SOC and TN, was significantly higher in the QTP grasslands. Our findings elucidated the response patterns, specialties, relationships, and factors influencing the QTP grasslands, which need to be considered in the development of process-based models and the sustainable use of alpine grasslands on QTP in the future. C1 [Yan, Liang; Li, Yong; Zhang, Xiaodong; Wang, Jinzhi; Wu, Haidong; Yan, Zhongqing; Zhang, Kerou; Kang, Xiaoming] Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China. [Yan, Liang; Li, Yong; Zhang, Xiaodong; Wang, Jinzhi; Wu, Haidong; Yan, Zhongqing; Zhang, Kerou; Kang, Xiaoming] Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China. [Yan, Liang; Li, Yong; Zhang, Xiaodong; Wang, Jinzhi; Wu, Haidong; Yan, Zhongqing; Zhang, Kerou; Kang, Xiaoming] Tibetan Autonomous Prefecture Aba, Sichuan Zoige Wetland Ecosyst Res Stn, Aba, Sichuan, Peoples R China. [Wang, Li] Univ Calif Davis, Davis, CA 95616 USA. RP Kang, XM (通讯作者)，Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China. EM xmkang@ucas.ac.cn TC 23 Z9 24 PD OCT PY 2020 VL 31 IS 16 BP 2369 EP 2378 DI 10.1002/ldr.3606 EA APR 2020 UT WOS:000526138600001 DA 2023-03-23 ER PT J AU Zhang, J Cui, XY Wang, YF Gongbuzeren Zhuang, MH Ji, BM AF Zhang, Jing Cui, Xiaoyong Wang, Yanfen Gongbuzeren Zhuang, Minghao Ji, Baoming TI Ecological consequence of nomad settlement policy in the pasture area of Qinghai-Tibetan Plateau: From plant and soil perspectives SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB The prevailing trend in pasture areas worldwide is that of mobile pastoralism to settlement, which produces a positive impact on pastoral livelihoods and livestock husbandry. However, the impact of nomad settlement on the grassland ecosystem is not well documented and remains debatable. In response, from 2001 to 2015, the central Chinese government initiated the Nomad Settlement Policy (NSP). In this study, we conducted a case study of the pastoral area of the Qinghai-Tibetan Plateau, to investigate impact of NSP on grassland ecological conditions including plants, soil and microorganisms. Results showed that grassland ecological conditions presented differentiation characteristics, with changes depending on the distance from settlements. The grassland ecological conditions showed heavy degradation near the settlement based on the classification of Qinghai-Tibetan Plateau grassland degradation, and gradual improvement with increasing distance from the settlement. Based on our investigation and previous studies, we found that intervention of NSP decreased the distance in livestock mobility and led to intensive grazing near the settlement, thereby increased grassland degradation. At the same time, the grassland maintained a relatively good ecological condition with the increase in distance from settlement, which may be attributed to short-period grazing and light trampling effects. Our findings provide new insight into the grassland ecological condition in the aftermath of NSP implementation, and also put forward some measures (e.g. multi-household grazing management, pastoral cooperative) to restore the grassland degradation. C1 [Zhang, Jing; Ji, Baoming] Beijing Forestry Univ, Coll Grassland Sci, Beijing, Peoples R China. [Zhang, Jing; Cui, Xiaoyong; Wang, Yanfen] Univ Chinese Acad Sci, Coll Life Sci, Beijing, Peoples R China. [Gongbuzeren] Southwestern Univ Finance & Econ, Populat Res Inst, Chengdu, Sichuan, Peoples R China. [Zhuang, Minghao] China Agr Univ, Coll Resources & Environm Sci, Beijing, Peoples R China. [Zhuang, Minghao] China Agr Univ, Natl Acad Agr Green Dev, Key Lab Plant Soil Interact MOE, Beijing, Peoples R China. RP Ji, BM (通讯作者)，Beijing Forestry Univ, Coll Grassland Sci, Beijing, Peoples R China.; Zhuang, MH (通讯作者)，China Agr Univ, Coll Resources & Environm Sci, Beijing, Peoples R China.; Zhuang, MH (通讯作者)，China Agr Univ, Natl Acad Agr Green Dev, Key Lab Plant Soil Interact MOE, Beijing, Peoples R China. EM zhuangminghao@pku.edu.cn; baomingji@bjfu.edu.cn TC 14 Z9 14 PD APR 15 PY 2020 VL 260 AR 110114 DI 10.1016/j.jenvman.2020.110114 UT WOS:000517661900017 DA 2023-03-23 ER PT J AU Yuan, LM Zhao, L Li, R Hu, GJ Du, EJ Qiao, YP Ma, L AF Yuan, Liming Zhao, Lin Li, Ren Hu, Guojie Du, Erji Qiao, Yongping Ma, Lu TI Spatiotemporal characteristics of hydrothermal processes of the active layer on the central and northern Qinghai-Tibet plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The spatial and temporal variations of the seasonal freeze-thaw cycles are important in understanding the ecological and hydrological processes and biogeochemical cycle associated with permafrost degradation caused by climate change, although observational data on the soil hydrothermal dynamics within the active layer of the permafrost region at the central and northern Qinghai-Tibet Plateau (QTP) are extremely scarce. In this study, soil temperature and moisture date from 11 observational sites along the Qinghai-Tibet Highway from 2010 to 2014 were used to analyze the freeze-thaw cycles of the active layer. The results revealed that mean annual ground surface temperature (MAGST) and mean annual temperature at the top of permafrost (TTOP) were the most closely related to the onset dates of soil freezing and thawing. The onset dates of soil freezing from bottom to top did not occur earlier than those from top to bottom. The differences between the onset dates of the two freezing directions and the proportion of bottom-up freezing depth increased with decreasing TTOP. The unfrozen water content of the cooling process was always higher than that of the warming process during the freezing stage. The hysteresis effect of the unfrozen water content could also be observed in the field experiment, and the maximum hysteresis levels occurred at their corresponding soil freezing points. Soil organic matter and soil moisture associated with vegetation cover are essential for water-heat exchanges between atmosphere and permafrost beneath active layer. We suggest that a better protected plant ecosystem, helps preserving the underlying permafrost on the Qinghai-Tibet Plateau. (C) 2020 Elsevier B.V. All rights reserved. C1 [Yuan, Liming; Li, Ren; Hu, Guojie; Du, Erji; Qiao, Yongping; Ma, Lu] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou 730000, Peoples R China. [Yuan, Liming; Ma, Lu] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhao, Lin] Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing 210044, Peoples R China. RP Zhao, L (通讯作者)，Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing 210044, Peoples R China. EM linzhao@lzb.ac.cn TC 23 Z9 26 PD APR 10 PY 2020 VL 712 AR 136392 DI 10.1016/j.scitotenv.2019.136392 UT WOS:000512369600123 DA 2023-03-23 ER PT J AU Yuan, ZQ Jin, HJ Wang, QF Wu, QB Li, GY Jin, XY Ma, Q AF Yuan, Zi-Qiang Jin, Hui-Jun Wang, Qing-Feng Wu, Qing-Bai Li, Guo-Yu Jin, Xiao-Ying Ma, Qiang TI Profile distributions of soil organic carbon fractions in a permafrost region of the Qinghai-Tibet Plateau SO PERMAFROST AND PERIGLACIAL PROCESSES DT Article AB Adequate characterization of soil organic carbon (SOC) fractions is essential to elucidate carbon dynamics in permafrost-affected ecosystems. SOC and its fractions were investigated across alpine ecosystems, including alpine swamp meadows (ASM), alpine meadows (AM) and alpine steppes (AS), in permafrost regions on the Qinghai-Tibet Plateau (QTP), southwest China. The density separation method was used to separate the SOC into light- and heavy-fraction organic carbon (LFOC and HFOC, respectively). Permafrost soils in the ASM had higher SOC, LFOC, and HFOC contents than in the AM. LFOC and HFOC contents were significantly correlated, but both were more closely related to SOC than to each other. On the ecological gradient from ASM to AS, the thickness of surficial organic horizons decreased while the thickness of mineral materials increased. SOC in the organic horizon and permafrost had high mineralization probability. At soil depths of 0-200 cm in ASM, AM, and AS, the SOC stocks were 123, 71, and 25 kg m(-2); LFOC stocks were 70, 49, and 12 kg m(-2); and HFOC stocks were 58, 37, and 15 kg m(-2), respectively. These results show that SOC fractions vary with vegetation type and active layer thickness, thus making SOC sensitive to changes in environmental conditions. Therefore, the decomposition of SOC in permafrost-affected soils of the QTP could be accelerated over a degrading permafrost and under a warming climate. C1 [Yuan, Zi-Qiang; Jin, Hui-Jun; Wang, Qing-Feng; Wu, Qing-Bai; Li, Guo-Yu; Jin, Xiao-Ying; Ma, Qiang] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. [Jin, Hui-Jun] Harbin Inst Technol, Sch Civil Engn, Harbin, Peoples R China. RP Jin, HJ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. EM hjjin@lzb.ac.cn TC 7 Z9 8 PD OCT PY 2020 VL 31 IS 4 BP 538 EP 547 DI 10.1002/ppp.2055 EA APR 2020 UT WOS:000524903700001 DA 2023-03-23 ER PT J AU Mou, D Tong, X Luozangangmao Ou, WY Liu, H Zhang, J Xie, JX Kazhuocairang AF Mou, Dan Tong, Xin Luozangangmao Ou, Weiyou Liu, Hua Zhang, Jing Xie, Jiuxiang Kazhuocairang TI Characterization of the complete chloroplast genome of a poisonous weed on alpine meadow on the Qinghai-Tibet Plateau, Ligularia virgaurea (Asteraceae: Senecioneae) SO MITOCHONDRIAL DNA PART B-RESOURCES DT Article AB Ligularia virgaurea (Asteraceae) is an indicator species of alpine meadow degradation. Here, the complete chloroplast genome of L. virgaurea was studied. The chloroplast genome of L. virgaurea is 151,185 bp in length. It has a typical quadripartite structure, containing a large single copy region of 83,369 bp, a small single copy region of 18,156 bp, and a pair of inverted repeated regions of 24,830 bp. A total of 132 functional genes were annotated, including eight rRNA genes, 37 tRNA genes, and 87 protein-coding genes. In the neighbour-joining phylogenetic tree based on chloroplast genome, the genus Ligularia clustered together, while L. virgaurea has a slightly more distant relationship with other Ligularia species. C1 [Mou, Dan; Zhang, Jing; Xie, Jiuxiang] Qinghai Univ, Coll Agr & Anim Husb, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Tong, Xin] Qinghai Nationalities Univ, Coll Ecol Environm & Resources, Xining, Peoples R China. [Luozangangmao; Kazhuocairang] Grassland Comprehens Profess Team Henan Mongolian, Youganning 811599, Peoples R China. [Ou, Weiyou; Liu, Hua] Qinghai Prov Gen Grassland Stn, Xining, Peoples R China. RP Kazhuocairang (通讯作者)，Grassland Comprehens Profess Team Henan Mongolian, Youganning 811599, Peoples R China.; Xie, JX (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Qinghai, Peoples R China. EM xiejx@qhu.edu.cn; 411271941@qq.com TC 0 Z9 0 PD APR 2 PY 2020 VL 5 IS 2 BP 1759 EP 1760 DI 10.1080/23802359.2020.1745706 UT WOS:000528757100001 DA 2023-03-23 ER PT J AU Chen, QY Niu, B Hu, YL Wang, J Lei, TZ Xu-Ri Zhou, JZ Xi, CW Zhang, GX AF Chen, Qiuyu Niu, Bin Hu, Yilun Wang, Jian Lei, Tianzhu Xu-Ri Zhou, Jizhong Xi, Chuanwu Zhang, Gengxin TI Multilevel Nitrogen Additions Alter Chemical Composition and Turnover of the Labile Fraction Soil Organic Matter via Effects on Vegetation and Microorganisms SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES DT Article AB Global nitrogen (N) deposition greatly impacts soil carbon sequestration. A 2-yr multiple N addition (0, 10, 20, 40, 80, and 160 kg N.ha(-1).yr(-1)) experiment was conducted in alpine grassland to illustrate the mechanisms underlying the observed soil organic matter (SOM) dynamics on the Qinghai-Tibet Plateau (QTP). Labile fraction SOM (LF-SOM) fingerprints were characterized by pyrolysis-gas chromatography/tandem-mass spectrometry, and microbial functional genes (GeoChip 4.6) were analyzed in conjunction with LF-SOM fingerprints to decipher the responses of LF-SOM transformation to N additions. The significant correlations between LF-SOM and microbial biomass, between organic compounds in LF-SOM and compound degradation-related genes, and between LF-SOM and net ecosystem exchange implied LF-SOM were the main fraction utilized by microorganisms and the most sensitive fraction to N additions. The LF-SOM increased at the lowest N addition levels (10 and 20 kg N.ha(-1).yr(-1)) and decreased at higher N addition levels (40 to 160 kg N.ha(-1).yr(-1)), but the decrease of LF-SOM was weakened at 160 kg N.ha(-1).yr(-1) addition. The nonlinear response of LF-SOM to N additions was due to the mass balance between plant inputs and microbial degradation. Plant-derived compounds in LF-SOM were more sensitive to N addition than microbial-derived and aromatic compounds. It is predicted that when the N deposition rate increased by 10 kg N.ha(-1).yr(-1) on the QTP, carbon sequestration in the labile fraction may increase by nearly 170% compared with that under the current N deposition rate. These findings provide insight into future N deposition impacts on LF-SOM preservation on the QTP. C1 [Chen, Qiuyu; Niu, Bin; Hu, Yilun; Xu-Ri; Zhang, Gengxin] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing, Peoples R China. [Chen, Qiuyu; Zhang, Gengxin] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Key Lab Alpine Ecol, Beijing, Peoples R China. [Chen, Qiuyu; Zhang, Gengxin] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. [Niu, Bin; Hu, Yilun] Univ Chinese Acad Sci, Beijing, Peoples R China. [Wang, Jian] Chinese Acad Sci, Key Lab Mt Surface Proc & Ecol Regulat, Inst Mt Hazards & Environm, Chengdu, Peoples R China. [Lei, Tianzhu] Chinese Acad Sci, Inst Geol & Geophys, Key Lab Petr Resources Res, Lanzhou, Peoples R China. [Zhou, Jizhong] Univ Oklahoma, Dept Microbiol & Plant Biol, Inst Environm Genom, Norman, OK 73019 USA. [Zhou, Jizhong] Univ Oklahoma, Sch Civil Engn & Environm Sci, Inst Environm Genom, Norman, OK 73019 USA. [Xi, Chuanwu] Univ Michigan, Sch Publ Hlth, Dept Environm Hlth Sci, Ann Arbor, MI 48109 USA. RP Zhang, GX (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing, Peoples R China.; Zhang, GX (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Key Lab Alpine Ecol, Beijing, Peoples R China.; Zhang, GX (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. EM zhangg@itpcas.ac.cn TC 4 Z9 4 PD APR PY 2020 VL 125 IS 4 AR e2019JG005316 DI 10.1029/2019JG005316 UT WOS:000535659000010 DA 2023-03-23 ER PT J AU Li, GR Li, XL Chen, WT Li, JF Zhu, HL Hu, XS Zhou, HK Sun, HQ AF Li, Guorong Li, Xilai Chen, Wenting Li, Jinfang Zhu, Haili Hu, Xiasong Zhou, Huakun Sun, Haiqun TI Effects of degradation severity on the physical, chemical and mechanical properties of topsoil in alpine meadow on the Qinghai-Tibet Plateau, west China SO CATENA DT Article AB Grassland degradation is an important cause of soil erosion and environment degradation in the world. So far few have quantitatively analyzed how the level of soil degradation of grassland affects the physical, chemical and mechanical traits of topsoil in the grassland, as well as the resistance of the surface root-soil composite to erosion. This paper attempts to fill this knowledge gap by studying the impact of soil degradation triggered by rodents with the advent of denudated patches on alpine meadow topsoil on the Qinghai-Tibet Plateau in west China. Field samples were collected at 0-2 cm to test soil nutrients, physical and mechanical properties, and samples collected at 0-5 cm depth were used to test the three-dimensional pore structure of the root-soil composite in different denudated patches. A combination of macroscopic and microscopic experiments was used to study the impacts of differently degraded meadows on topsoil properties and thereby the ecological environment. Results showed that the severity of soil degradation lessened gradually from the center of the denudated patches to the periphery. Soil moisture, density and root volume in the severely degraded zone were significantly lower than in moderately and mildly degraded ones. The volumetric porosity ratio of severely degraded meadows is 4.65% and 9.55% higher than that of moderately and slightly degraded meadows, respectively, The average surface porosity increased by 4.37 and 9.58%, respectively, the average soil shear strength decreased by 36.0% and 52.3%, respectively, and the soil compactness decreased 54.8% and 90.8%, respectively, and the nutrient content of the root-soil composite also decreased with the soil degradation degree. Moreover, soil pore volume was inversely related to its shear strength that decreases quickly with degradation severity. The changes in the physical and mechanical characteristics of the topsoil in degraded meadows weakened its erosion resistance, which can lead to infertile and deteriorated soil. The strategies for restoring the degraded meadows should aim at increasing vegetation roots and litter quantity in the topsoil and stabilizing soil surface structure to create an environment for pioneering vegetation such as mosses and lichens to become established first so that the degraded meadows can recover naturally. C1 [Li, Guorong; Li, Xilai] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. [Li, Guorong; Li, Xilai; Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Reg Qinghai Prov, Xining 81008, Qinghai, Peoples R China. [Li, Guorong; Chen, Wenting; Li, Jinfang; Zhu, Haili; Hu, Xiasong] Qinghai Univ, Geol Engn Dept, Xining 810016, Qinghai, Peoples R China. [Li, Guorong] Key Lab Cenozo Resource & Env North Margin Tibeta, Xining 810016, Qinghai, Peoples R China. [Li, Xilai; Sun, Haiqun] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Qinghai, Peoples R China. RP Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. EM xilai-li@163.com TC 14 Z9 14 PD APR PY 2020 VL 187 AR 104370 DI 10.1016/j.catena.2019.104370 UT WOS:000514020400046 DA 2023-03-23 ER PT J AU Li, Q AF Li, Quan TI Solar forcing of desert vegetation and drought frequency during the last 2700 years in the interior Qaidam Basin, northeastern Tibetan Plateau SO SCIENCE CHINA-EARTH SCIENCES DT Article AB Knowledge of long-term change in vegetation and climate in semi-arid/arid regions is essential for the study of current climate and development of mitigation strategies against severe drought. Here, a fossil pollen record of annually-varved core from Sugan Lake in interior Qaidam Basin was quantitatively analyzed to reconstruct changes in vegetation, floristic diversity and drought frequency. Results of biomization suggested that regional vegetation was desert vegetation with three short-term occupations of temperate steppe/xerophytic shrub during the last 2700 years. Floristic diversity generally increased/decreased with the expansion/degradation of desert vegetation. Moisture fluctuations showed three distinct stages (extremely dry between 742BC and similar to AD500, relatively wet with an increasing trend between similar to AD500 and 1200 and relatively wet with frequent fluctuations after AD1200), interrupted by 14 drought events. Spectral analysis and continuous wavelet transform of moisture variation revealed 200- and 120-year cycles. According to cross-wavelet transform analysis, major drought frequency of similar to 200-year was explicitly correlated to solar activity. It's suggested that the centennial-scale drought frequency was mainly driven by solar activity, through modulation of large-scale atmospheric circulation. Furthermore, the effect of surface temperature-evaporation and uplifting/subsiding air flow should be notable. The climatic drought in interior Qaidam Basin could be intensified under the continuous global warming. C1 [Li, Quan] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. RP Li, Q (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM liquan@igsnrr.ac.cn TC 4 Z9 5 PD APR PY 2020 VL 63 IS 4 BP 561 EP 574 DI 10.1007/s11430-019-9550-7 UT WOS:000519897000007 DA 2023-03-23 ER PT J AU Tomaszewska, MA Nguyen, LH Henebry, GM AF Tomaszewska, Monika A. Nguyen, Lan H. Henebry, Geoffrey M. TI Land surface phenology in the highland pastures of montane Central Asia: Interactions with snow cover seasonality and terrain characteristics SO REMOTE SENSING OF ENVIRONMENT DT Article AB Many studies have shown that high elevation environments are among very sensitive to climatic changes and where impacts are exacerbated. Across Central Asia, which is especially vulnerable to climate change due to aridity, the ability of global climate projections to capture the complex dynamics of mountainous environments is particularly limited. Over montane Central Asia, agropastoralism constitutes a major portion of the rural economy. Extensive herbaceous vegetation forms the basis of rural economies in Kyrgyzstan. Here we focus on snow cover seasonality and the effects of terrain on phenology in highland pastures using remote sensing data for 2001-2017. First, we describe the thermal regime of growing season using MODerate Resolution Imaging Spectrometer (MODIS) land surface temperature (LST) data, analyzing the modulation by elevation, slope, and aspect. We then characterized the phenology in highland pastures with metrics derived from modeling the land surface phenology using Landsat normalized difference vegetation index (NDVI) time series together with MODIS LST data. Using rank correlations, we then analyzed the influence of four metrics of snow cover seasonality calculated from MODIS snow cover composites-first date of snow, late date of snow, duration of snow season, and the number of snow-covered dates (SCD)-on two key metrics of land surface phenology in the subsequent growing season, specifically, peak height (PH; the maximum modeled NDVI) and thermal time to peak (TTP; the amount of growing degree-days accumulated during modeled green-up phase). We evaluated the role of terrain features in shaping the relationships between snow cover metrics and land surface phenology metrics using exact multinomial tests of equivalence. Key findings include (1) a positive relationship between SCD and PH occurred in over 1664 km(2) at p < 0.01 and 5793 km(2) at p < 0.05, which account for > 8% of 68,881 km(2) of the pasturelands analyzed in Kyrgyzstan; (2) more negative than positive correlations were found between snow cover onset and PH, and more positive correlations were observed between snowmelt timing and PH, indicating that a longer snow season can positively influence PH; (3) significant negative correlations between TTP and SCD appeared in 1840 km(2) at p < 0.01 and 6208 km(2) at p < 0.05, and a comparable but smaller area showed negative correlations between TTP and last date of snow (1538 km(2) at p < 0.01 and 5188 km(2) at p < 0.05), indicating that under changing climatic conditions toward earlier spring warming, decreased duration of snow cover may lead to lower pasture productivity, thereby threatening the sustainability of montane agropastoralism; and (4) terrain had a stronger influence on the timing of last date of snow cover than on the number of snow-covered dates, with slope being more important than aspect, and the strongest effect appearing from the interaction of aspect and steeper slopes. In this study, we characterized the snow-phenology interactions in highland pastures and revealed strong dependencies of pasture phenology on timing of snowmelt and the number of snow-covered dates. C1 [Tomaszewska, Monika A.; Nguyen, Lan H.] South Dakota State Univ, Geospatial Sci Ctr Excellence, Brookings, SD 57007 USA. [Henebry, Geoffrey M.] Michigan State Univ, Dept Geog Environm & Spatial Sci, E Lansing, MI 48824 USA. [Tomaszewska, Monika A.; Henebry, Geoffrey M.] Michigan State Univ, Ctr Global Change & Earth Observat, E Lansing, MI 48823 USA. [Nguyen, Lan H.] Univ Calgary, Dept Biol Sci, Calgary, AB, Canada. RP Henebry, GM (通讯作者)，Michigan State Univ, Dept Geog Environm & Spatial Sci, E Lansing, MI 48824 USA. EM henebryg@msu.edu TC 29 Z9 29 PD APR PY 2020 VL 240 AR 111675 DI 10.1016/j.rse.2020.111675 UT WOS:000523955300029 DA 2023-03-23 ER PT J AU Wen, J Qin, RM Zhang, SX Yang, XY Xu, MH AF Wen, Jing Qin, Ruimin Zhang, Shixiong Yang, Xiaoyan Xu, Manhou TI Effects of long-term warming on the aboveground biomass and species diversity in an alpine meadow on the Qinghai-Tibetan Plateau of China SO JOURNAL OF ARID LAND DT Article AB Ecosystems in high-altitude regions are more sensitive and respond more rapidly than other ecosystems to global climate warming. The Qinghai-Tibet Plateau (QTP) of China is an ecologically fragile zone that is sensitive to global climate warming. It is of great importance to study the changes in aboveground biomass and species diversity of alpine meadows on the QTP under predicted future climate warming. In this study, we selected an alpine meadow on the QTP as the study object and used infrared radiators as the warming device for a simulation experiment over eight years (2011-2018). We then analyzed the dynamic changes in aboveground biomass and species diversity of the alpine meadow at different time scales, including an early stage of warming (2011-2013) and a late stage of warming (2016-2018), in order to explore the response of alpine meadows to short-term (three years) and long-term warming (eight years). The results showed that the short-term warming increased air temperature by 0.31 degrees C and decreased relative humidity by 2.54%, resulting in the air being warmer and drier. The long-term warming increased air temperature and relative humidity by 0.19 degrees C and 1.47%, respectively, and the air tended to be warmer and wetter. The short-term warming increased soil temperature by 2.44 degrees C and decreased soil moisture by 12.47%, whereas the long-term warming increased soil temperature by 1.76 degrees C and decreased soil moisture by 9.90%. This caused the shallow soil layer to become warmer and drier under both short-term and longterm warming. Furthermore, the degree of soil drought was alleviated with increased warming duration. Under the long-term warming, the importance value and aboveground biomass of plants in different families changed. The importance values of grasses and sedges decreased by 47.56% and 3.67%, respectively, while the importance value of weeds increased by 1.37%. Aboveground biomass of grasses decreased by 36.55%, while those of sedges and weeds increased by 8.09% and 15.24%, respectively. The increase in temperature had a non-significant effect on species diversity. The species diversity indices increased at the early stage of warming and decreased at the late stage of warming, but none of them reached significant levels (P>0.05). Species diversity had no significant correlation with soil temperature and soil moisture under both short-term and long-term warming. Soil temperature and aboveground biomass were positively correlated in the control plots (P=0.014), but negatively correlated under the long-term warming (P=0.013). Therefore, eight years of warming aggravated drought in the shallow soil layer, which is beneficial for the growth of weeds but not for the growth of grasses. Warming changed the structure of alpine meadow communities and had a certain impact on the community species diversity. Our studies have great significance for the protection and effective utilization of alpine vegetation, as well as for the prevention of grassland degradation or desertification in high-altitude regions. C1 [Wen, Jing; Qin, Ruimin; Zhang, Shixiong; Yang, Xiaoyan; Xu, Manhou] Taiyuan Normal Univ, Jinzhong 030619, Peoples R China. RP Xu, MH (通讯作者)，Taiyuan Normal Univ, Jinzhong 030619, Peoples R China. EM xumanhou@163.com TC 12 Z9 14 PD MAR PY 2020 VL 12 IS 2 BP 252 EP 266 DI 10.1007/s40333-020-0064-z EA MAR 2020 UT WOS:000522574200003 DA 2023-03-23 ER PT J AU Liu, M Zhang, ZC Sun, J Xu, M Ma, BB Tijjani, SB Chen, YJ Zhou, QP AF Liu, Miao Zhang, Zhenchao Sun, Jian Xu, Ming Ma, Baibing Tijjani, Sadiy Baba Chen, You-jun Zhou, Qingping TI The Response of Vegetation Biomass to Soil Properties along Degradation Gradients of Alpine Meadow at Zoige Plateau SO CHINESE GEOGRAPHICAL SCIENCE DT Article AB Alpine grassland of the Tibetan Plateau has undergone severe degradation, even desertification. However, several questions remain to be answered, especially the response mechanisms of vegetation biomass to soil properties. In this study, an experiment on degradation gradients was conducted in an alpine meadow at the Zoige Plateau in 2017. Both vegetation characteristics and soil properties were observed during the peak season of plant growth. The classification and regression tree model (CART) and structural equation modelling (SEM) were applied to screen the main factors that govern the vegetation dynamics and explore the interaction of these screened factors. Both aboveground biomass (AGB) and belowground biomass (BGB) experienced a remarkable decrease along the degradation gradients. All soil properties experienced significant variations along the degradation gradients at the 0.05 significance level. Soil physical and chemical properties explained 54.78% of the variation in vegetation biomass along the degradation gradients. AGB was mainly influenced by soil water content (SWC), soil bulk density (SBD), soil organic carbon (SOC), soil total nitrogen (STN), and pH. Soil available nitrogen (SAN), SOC and pH, had significant influence on BGB. Most soil properties had positive effects on AGB and BGB, while SBD and pH had a slightly negative effect on AGB and BGB. The correlations of SWC with AGB and BGB were relatively less significant than those of other soil properties. Our results highlighted that the soil properties played important roles in regulating vegetation dynamics along the degradation gradients and that SWC is not the main factor limiting plant growth in the humid Zoige region. Our results can provide guidance for the restoration and improvement of degraded alpine grasslands on the Tibetan Plateau. C1 [Liu, Miao; Zhang, Zhenchao; Sun, Jian; Xu, Ming; Ma, Baibing] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr,Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. [Sun, Jian] Chinese Acad Sci, State Key Lab Urban & Reg Ecol, Res Ctr Ecoenvironm Sci, Beijing 100085, Peoples R China. [Xu, Ming; Tijjani, Sadiy Baba] Rutgers State Univ, Sch Environm & Biol Sci, Dept Ecol Evolut & Nat Resources, New Brunswick, NJ 08901 USA. [Xu, Ming] Henan Univ, Coll Environm & Planning, Kaifeng 475004, Peoples R China. [Ma, Baibing] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Chen, You-jun; Zhou, Qingping] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. RP Sun, J; Xu, M (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr,Chinese Ecosyst Res Network, Beijing 100101, Peoples R China.; Sun, J (通讯作者)，Chinese Acad Sci, State Key Lab Urban & Reg Ecol, Res Ctr Ecoenvironm Sci, Beijing 100085, Peoples R China.; Xu, M (通讯作者)，Rutgers State Univ, Sch Environm & Biol Sci, Dept Ecol Evolut & Nat Resources, New Brunswick, NJ 08901 USA.; Xu, M (通讯作者)，Henan Univ, Coll Environm & Planning, Kaifeng 475004, Peoples R China. EM sunjian@igsnrr.ac.cn; mingxu@igsnrr.ac.cn TC 10 Z9 12 PD JUN PY 2020 VL 30 IS 3 BP 446 EP 455 DI 10.1007/s11769-020-1116-1 EA MAR 2020 UT WOS:000521904600002 DA 2023-03-23 ER PT J AU Luo, CY Wang, SP Zhang, LR Wilkes, A Zhao, L Zhao, XQ Xu, SX Xu, B AF Luo, Caiyun Wang, Shiping Zhang, Lirong Wilkes, Andreas Zhao, Liang Zhao, Xinquan Xu, Shixiao Xu, Burenbayin TI CO2, CH4 and N2O fluxes in an alpine meadow on the Tibetan Plateau as affected by N-addition and grazing exclusion SO NUTRIENT CYCLING IN AGROECOSYSTEMS DT Article AB Limited understanding of the effects of enhanced nitrogen (N) addition and grazing exclusion (E) on greenhouse gases fluxes (GHGs: CO2, CH4, and N2O) in grasslands constrains our ability to respond to the challenges of future climate change. In this study, we conducted a field experiment using a static closed opaque chamber to investigate the response of GHG fluxes to N addition (69 kg N ha(-1) year(-1) applied in 3 splits) and grazing exclusion in an alpine meadow on the Tibetan Plateau during the growing seasons from 2011 to 2013. Our results showed that winter grazing significantly raised soil temperature (ST), while grazing exclusion (E) had no effect on soil moisture (SM), and N fertilizer (F) had no effect on ST or SM. Aboveground biomass (AB) and root biomass (RB) were not significantly affected by E in 2011-2013 (p > 0.05), but F significantly affected AB and RB (p < 0.05). Compared with winter grazing, only E substantially reduced seasonal mean CO2 emissions (by about 20.1%) during the experimental period. E did not significantly directly affect CH4 uptake, whereas N addition reduced seasonal mean CH4 uptake by about 6.5%, and N addition changed seasonal average absorption of N2O into an emission source. CO2 flux is the major contributor to CO2 equivalent emissions in this area. Our results indicate that exclosure from livestock grazing might be a promising measure to reduce CO2 emissions, while enhanced N addition might reduce CH4 uptake and increase N2O emission in the alpine meadow under future climate change. C1 [Luo, Caiyun; Zhao, Liang; Zhao, Xinquan; Xu, Shixiao] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Haibei Alpine Grassland Ecosyst Res Stn, Xining 810008, Peoples R China. [Wang, Shiping; Zhang, Lirong] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. [Wang, Shiping] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Wilkes, Andreas] Values Dev Ltd, Bury St Edmunds IP33 3EQ, Suffolk, England. [Xu, Burenbayin] Xinyang Normal Univ, 237 Nanhu Rd, Xinyang 464000, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. EM wangsp@itpcas.ac.cn TC 9 Z9 10 PD MAY PY 2020 VL 117 IS 1 BP 29 EP 42 DI 10.1007/s10705-020-10062-0 EA MAR 2020 UT WOS:000521772800001 DA 2023-03-23 ER PT J AU Yu, LF Wang, H Wang, YH Zhang, ZH Chen, LT Liang, NS He, JS AF Yu, Lingfei Wang, Hao Wang, Yonghui Zhang, Zhenhua Chen, Litong Liang, Naishen He, Jin-Sheng TI Temporal variation in soil respiration and its sensitivity to temperature along a hydrological gradient in an alpine wetland of the Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Wetlands are predicted to experience lowered water tables due to permafrost degradation in the Tibetan Plateau. These changes may affect carbon cycle processes such as soil respiration (R-s). However, the magnitude, patterns and controls of R-s remain poorly understood in alpine wetlands with their distinct hydrological regimes. Here, we conducted a field study on R-s from 2012 to 2014 in three alpine ecosystems on the Tibetan Plateau-fen, wet meadow and meadow-with soil water decreases along hydrological gradients. From 2012 to 2014, the annual R-s was 128.9-193.3 g C m(-2)yr(-1), 281.5-342.9 g C m(-2)yr(-1), and 663.4-709.1 g C m(-2)yr(-1) for the fen, wet meadow, and meadow, respectively. An abrupt increase in CO2 emissions was caused by the spring thawing of the frozen soil in the fen and wet meadow, contributing 20.4-37.6% and 13.2-17.4%, respectively, to the annual R-s. The diurnal variation in the R-s was site specific among the three ecosystems, with one peak at 1300 h in the fen and meadow and two peaks at 1300 h and 1900 h in the wet meadow. The temperature-independent components of the diurnal variation in R-s were generally explained by photosynthetically active radiation in the fen and wet meadow, but not in the meadow. The temperature sensitivity of the R-s (unconfounded Q(10)) varied significantly among the three ecosystems, with the highest values occurring in the wet meadow, implying that permafrost thaw-induced wetland drying from the fen to the wet meadow could enhance the response of CO2 emissions to climate warming but that further drying from the wet meadow to the meadow probably weakens the effect of warming on the R-s. Our study emphasized the important role of the hydrological regime in regulating the temporal variation in R-s and its response to climate warming. C1 [Yu, Lingfei; He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Key Lab Earth Surface Proc,Minist Educ, 5 Yiheyuan Rd, Beijing 100871, Peoples R China. [Yu, Lingfei] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, 20 Nanxincun, Beijing 100093, Peoples R China. [Wang, Hao] Lanzhou Univ, Inst Innovat Ecol, 768 Jiayuguan W Rd, Lanzhou 730020, Peoples R China. [Wang, Yonghui] Inner Mongolia Univ, Sch Ecol & Environm, Dept Ecol, 235 West Coll Rd, Hohhot 010021, Peoples R China. [Zhang, Zhenhua; Chen, Litong] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, 23 Xining Rd, Xining 810008, Peoples R China. [Liang, Naishen] Natl Inst Environm Studies, Ctr Global Environm Res, Tsukuba, Ibaraki 3058506, Japan. [He, Jin-Sheng] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland & Agroecosyst, 768 Jiayuguan W Rd, Lanzhou 730020, Peoples R China. RP He, JS (通讯作者)，Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Key Lab Earth Surface Proc,Minist Educ, 5 Yiheyuan Rd, Beijing 100871, Peoples R China. EM jshe@pku.edu.cn TC 18 Z9 19 PD MAR 15 PY 2020 VL 282 AR 107854 DI 10.1016/j.agrformet.2019.107854 UT WOS:000525813300001 DA 2023-03-23 ER PT J AU Yuan, ZQ Epstein, H Li, GY AF Yuan, Zi-Qiang Epstein, Howard Li, Guo-Yu TI Grazing exclusion did not affect soil properties in alpine meadows in the Tibetan permafrost region SO ECOLOGICAL ENGINEERING DT Article AB Grazing exclusion (GE) is widely used in the Tibetan Plateau of China to restore degraded grasslands. However, the effects of GE on vegetation and soil properties in alpine meadows are still not well understood. We compared GE with adjacent continuously grazing alpine meadows at five sites to evaluate the impact of GE (10-14 years) on vegetation and soil properties in the permafrost region of the Tibetan Plateau. We collected soil samples at two soil depths (0-20 and 20-40 cm) from GE and adjacent grazing sites. The results showed that GE and Site had significant effects on aboveground biomass and cover, Site but not GE had significant effects on diversity index. GE significantly increased the aboveground biomass and cover in three of the five sites, particularly where vegetation cover was greatest. At each site, GE had inconsistent effects on plant species diversity (a positive effect at one site, no significant effects at three sites, and a negative effect at the other site). No significant differences were found between GE and adjacent grazing grasslands in soil properties (soil organic carbon [SOC], total nitrogen [N], total phosphorus [P], available P, mineral N, microbial biomass carbon [MBC] and nitrogen [MBN] and pH) for both soil depths at each site. A general linear mixed model confirmed that site and sampling depth, rather than GE, significantly affected soil properties (except for MBC). Both total aboveground biomass and cover were positively correlated with soil total P, MBC and MBN, were negatively correlated with available P and pH, and were not significantly correlated with SOC and total N. The results indicate that long-term GE (10-14 years) in alpine meadow did not significantly impact soil properties, and its impact on plant biomass and vegetation cover depends on the vegetation condition of the site. Our results can provide new insights for alpine meadow management in the permafrost region of the Tibetan Plateau. C1 [Yuan, Zi-Qiang; Li, Guo-Yu] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. [Yuan, Zi-Qiang] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Beiluhe Observat Stn Frozen Soil Environm & Engn, Lanzhou 730000, Peoples R China. [Epstein, Howard] Univ Virginia, Dept Environm Sci, Charlottesville, VA 22904 USA. RP Li, GY (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. EM guoyuli@lzb.ac.cn TC 8 Z9 9 PD MAR 15 PY 2020 VL 147 AR 105657 DI 10.1016/j.ecoleng.2019.105657 UT WOS:000519577900001 DA 2023-03-23 ER PT J AU Anslan, S Rad, MA Buckel, J Galindo, PE Kai, JL Kang, WG Keys, L Maurischat, P Nieberding, F Reinosch, E Tang, HD Tran, TV Wang, YY Schwalb, A AF Anslan, Sten Rad, Mina Azizi Buckel, Johannes Galindo, Paula Echeverria Kai, Jinlei Kang, Wengang Keys, Laura Maurischat, Philipp Nieberding, Felix Reinosch, Eike Tang, Handuo Tuong Vi Tran Wang, Yuyang Schwalb, Antje TI Reviews and syntheses: How do abiotic and biotic processes respond to climatic variations in the Nam Co catchment (Tibetan Plateau)? SO BIOGEOSCIENCES DT Review AB The Tibetan Plateau (TP) is the largest alpine plateau on Earth and plays an important role in global climate dynamics. On the TP, climate change is happening particularly fast, with an increase in air temperature twice the global average. The particular sensitivity of this high mountain environment allows observation and tracking of abiotic and biotic feedback mechanisms. Closed lake systems, such as Nam Co on the central TP, represent important natural laboratories for tracking past and recent climatic changes, as well as geo-biological processes and interactions within their respective catchments. This review gives an interdisciplinary overview of past and modern environmental changes using Nam Co as a case study. In the catchment area, ongoing rise in air temperature forces glaciers to melt, contributing to a rise in lake level and changes in water chemistry. Some studies base their conclusions on inconsistent glacier inventories, but an ever-increasing deglaciation and thus higher water availability have persisted over the last few decades. Increasing water availability causes translocation of sediments, nutrients and dissolved organic matter to the lake, as well as higher carbon emissions to the atmosphere. The intensity of grazing has an additional and significant effect on CO2 fluxes, with moderate grazing enhancing belowground allocation of carbon while adversely affecting the C sink potential through reduction of above-surface and subsurface biomass at higher grazing intensities. Furthermore, increasing pressure from human activities and livestock grazing are enhancing grassland degradation processes, thus shaping biodiversity patterns in the lake and catchment. The environmental signal provided by taxon-specific analysis (e.g., diatoms and ostra-cods) in Nam Co revealed profound climatic fluctuations between warmer-cooler and wetter-drier periods since the late Pleistocene and an increasing input of freshwater and nutrients from the catchment in recent years. Based on the reviewed literature, we outline perspectives to further understand the effects of global warming on geodiversity and biodiversity and their interplay at Nam Co, which acts as a case study for potentially TP-level or even worldwide processes that are currently shaping high mountain areas. C1 [Anslan, Sten] Tech Univ Carolo Wilhelmina Braunschweig, Zool Inst, Mendelssohnstr 4, D-38106 Braunschweig, Germany. [Anslan, Sten; Rad, Mina Azizi; Galindo, Paula Echeverria; Kang, Wengang; Nieberding, Felix; Schwalb, Antje] Tech Univ Carolo Wilhelmina Braunschweig, Inst Geosyst & Bioindicat, Langer Kamp 19C, D-38106 Braunschweig, Germany. [Rad, Mina Azizi] Max Planck Inst Biogeochem, D-07745 Jena, Germany. [Buckel, Johannes] Tech Univ Carolo Wilhelmina Braunschweig, Inst Geophys & Extraterr Phys, Mendelssohnstr 3, D-38106 Braunschweig, Germany. [Kai, Jinlei; Tang, Handuo; Wang, Yuyang] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing, Peoples R China. [Kai, Jinlei; Tang, Handuo; Wang, Yuyang] Univ Chinese Acad Sci, Beijing, Peoples R China. [Keys, Laura] Friedrich Schiller Univ Jena, Inst Geog, Lobdergraben 32, D-07743 Jena, Germany. [Maurischat, Philipp] Leibniz Univ Hannover, Inst Soil Sci, Herrenhauser Str 2, D-30419 Hannover, Germany. [Nieberding, Felix] GFZ German Res Ctr Geosci, D-14473 Potsdam, Germany. [Reinosch, Eike] Tech Univ Carolo Wilhelmina Braunschweig, Inst Geodesy & Photogrammetry, Bienroder Weg 81, D-38106 Braunschweig, Germany. [Tuong Vi Tran] Leibniz Univ Hannover, Inst Fluid Mech & Environm Phys Civil Engn, Appelstr 9A, D-30167 Hannover, Germany. RP Nieberding, F (通讯作者)，Tech Univ Carolo Wilhelmina Braunschweig, Inst Geosyst & Bioindicat, Langer Kamp 19C, D-38106 Braunschweig, Germany.; Nieberding, F (通讯作者)，GFZ German Res Ctr Geosci, D-14473 Potsdam, Germany. EM f.nieberding@tu-braunschweig.de TC 22 Z9 23 PD MAR 6 PY 2020 VL 17 IS 5 BP 1261 EP 1279 DI 10.5194/bg-17-1261-2020 UT WOS:000518835100003 DA 2023-03-23 ER PT J AU Ai, ZT An, R Lu, CH Chen, YH AF Ai, Zetian An, Ru Lu, Caihong Chen, Yuehong TI Mapping of native plant species and noxious weeds to investigate grassland degradation in the Three-River Headwaters region using HJ-1A/HSI imagery SO INTERNATIONAL JOURNAL OF REMOTE SENSING DT Article AB Characterized by an alpine meadow, the ecological environment system in the ?Three-River Headwaters? region (TRHR) is considered to be a typical fragile ecological system. Numerous observations and research results have indicated that grassland degradation has occurred in the TRHR in recent years. However, research related to utilize the species information of grass communities to monitor grassland degradation remains rare. Therefore, the aim of this study is to produce the distribution maps of native plant species and noxious weeds to investigate grassland degradation for livestock farming perspective. In this study, the fused HJ-1A/HSI data was combined with field investigation samples to define the coverage of native plant species and noxious weeds at different coverage levels. Then, coverage distribution maps of native plant species and noxious weeds were produced by using support vector machine (SVM) classification and random forests (RF) regression methods. Meanwhile, the overall accuracy (OA) and root-mean-square error (RMSE) of each coverage map were assessed. Finally, a grassland degradation map was derived according to the native plant species and noxious weeds cover information. The experimental results show that (1) the spectral feature of native plant species and noxious weeds can be distinguished based on field measurement spectra in the TRHR; (2) the fractional coverage of native plant species and noxious weeds can be relatively accurately estimated when coverage is divided into nine levels; (3) the grass coverage estimation accuracies of SVM classification are similar with these of RF regression method. The OAs of SVM classification are 69.7% at nine grassland coverage levels for native plant species and noxious weeds, and corresponding RMSEs are 8.2% and 8.0%, respectively; and (4) the coverage of native plant species is generally higher than that of the noxious weeds in the study area. C1 [Ai, Zetian; An, Ru; Chen, Yuehong] Hohai Univ, Sch Earth Sci & Engn, Nanjing 211100, Jiangsu, Peoples R China. [Ai, Zetian] Chuzhou Univ, Sch Geog Informat & Tourism, Chuzhou, Anhui, Peoples R China. [Lu, Caihong] Marine Technol Ctr Zhejiang Prov, Hangzhou, Zhejiang, Peoples R China. RP An, R (通讯作者)，Hohai Univ, Sch Earth Sci & Engn, Nanjing 211100, Jiangsu, Peoples R China. EM anrunj@163.com TC 4 Z9 4 PD MAR 3 PY 2020 VL 41 IS 5 BP 1813 EP 1838 DI 10.1080/01431161.2019.1675324 UT WOS:000499576400008 DA 2023-03-23 ER PT J AU Li, ZW Gao, P Hu, XY Yi, YJ Pan, BZ You, YC AF Li, Zhiwei Gao, Peng Hu, Xuyue Yi, Yujun Pan, Baozhu You, Yuchi TI Coupled impact of decadal precipitation and evapotranspiration on peatland degradation in the Zoige basin, China SO PHYSICAL GEOGRAPHY DT Article AB This study quantified the temporal properties of precipitation and actual evapotranspiration (ETa) in the Zoige basin of the Yellow River source region, China during the 1967-2011 period, as well as their influence to the area reduction of peatland. We extracted areas of different land-use and land-cover (LULC) types and obtained daily precipitation data. Then, we calculated annual precipitation (AP) and specific cumulative precipitation (SCP), which is the sum of precipitation to the date when an image was taken, and showed that the peatland areas were strongly affected by SCP. Using a modified Penman-Monteith equation, we calculated ETa for each LULC type and the area-weighted ones to show that the area-weighted total ETa was mainly contributed from grassland and peatland, which was between 450 and 550 mm. Temporal trends of the ratio of SCP to evapotranspiration showed that precipitation was generally greater than evapotranspiration rate not only during the summer but also over the 1967-2011 period. This trend failed to completely explain the continuous decrease of peatland area in the Zoige basin in decades. The draining effect of artificial ditches and natural gullies might play an additional role in causing peatland degradation but requires further process-based studies. C1 [Li, Zhiwei] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining, Peoples R China. [Li, Zhiwei; Hu, Xuyue; You, Yuchi] Changsha Univ Sci & Technol, Key Lab Water Sediment Sci & Water Disaster Preve, Sch Hydraul Engn, Changsha, Peoples R China. [Gao, Peng] Syracuse Univ, Dept Geog, New York, NY USA. [Yi, Yujun] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat & Pollut Con, Beijing, Peoples R China. [Pan, Baozhu] Xian Univ Technol, State Key Lab Base Ecohydraul Engn Arid Area, Xian, Peoples R China. RP Gao, P (通讯作者)，Syracuse Univ, Dept Geog, New York, NY USA. EM pegao@maxwell.syr.edu TC 7 Z9 8 PD MAR 3 PY 2020 VL 41 IS 2 BP 145 EP 168 DI 10.1080/02723646.2019.1620579 UT WOS:000518140600003 DA 2023-03-23 ER PT J AU Wang, R Dong, ZB Zhou, ZC AF Wang, Rui Dong, Zhibao Zhou, Zhengchao TI Effect of decreasing soil frozen depth on vegetation growth in the source region of the Yellow River for 1982-2015 SO THEORETICAL AND APPLIED CLIMATOLOGY DT Article AB Climate warming impacts on frozen ground degradation may cause large-scale consequences to terrestrial ecosystems within the source region of the Yellow River (SRYR). Spatial and temporal variations in the soil frozen depth (SFD) in SRYR were estimated using the Stefan equation for 1982-2015 and SFD effects on alpine vegetation were analyzed. Mean SFD during 1982-2015 decreased at a rate of 6.01 cm/10a, and the areal extent of the SFD greater than 160 cm decreased by 26.3%. Normalized difference vegetation index (NDVI) in the growing season (NDVIgr) discontinuously increased at a rate of 0.003/10a, increasing in 1982-2000 and declining in 2001-2015. The NDVIgr was significantly correlated to the decreasing SFD, showing a stronger relationship than that with temperature and precipitation. Comparisons before and after 2000 showed that negative relationships between SFD and NDVIgr became positive. Responses of vegetation growth to frozen ground degradation depended on different rates of decreasing SFD. Rapid decreases in SFD after 2000 led to increased evapotranspiration and reduced soil water, which negatively affected vegetation growth. Negative impacts of human activities on vegetation changed to positive contributions from the periods of 1982-2000 to 2001-2015; however, the effect was less than that of climate change and frozen ground degradation. This study provides a foundation for research on frozen ground changes and the impacts on ecological environments. C1 [Wang, Rui; Dong, Zhibao; Zhou, Zhengchao] Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Peoples R China. RP Wang, R (通讯作者)，Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Peoples R China. EM wangrui227@126.com TC 9 Z9 13 PD MAY PY 2020 VL 140 IS 3-4 BP 1185 EP 1197 DI 10.1007/s00704-020-03141-3 EA MAR 2020 UT WOS:000518064000002 DA 2023-03-23 ER PT J AU Guo, XW Dai, LC Li, Q Qian, DW Cao, GM Zhou, HK Du, YG AF Guo, Xiaowei Dai, Licong Li, Qian Qian, Dawen Cao, Guangmin Zhou, Huakun Du, Yangong TI Light Grazing Significantly Reduces Soil Water Storage in Alpine Grasslands on the Qinghai-Tibet Plateau SO SUSTAINABILITY DT Article AB The degradation of alpine grasslands directly affects their ability to conserve water, but changes in soil water storage in grassland under different degrees of degradation are poorly understood. Here, we selected four grassland plots along a degradation gradient: no-degradation grassland (NG), lightly degraded grassland (LG), moderately degraded grassland (MG) and severely degraded grassland (SG). We then applied an automatic soil moisture monitoring system to study changes in soil water storage processes. Results revealed significant (p < 0.05) differences in soil water storage among NG, LG, MG and SG. Specifically, LG lost 35.9 mm of soil water storage compared with NG, while soil water storage in LG, MG and SG decreased by 24.5%, 32.1% and 36.7%, respectively. The shallow groundwater table, air temperature and grass litter were the key controlling factors of soil water storage in the grassland. Grazing and future global warming will significantly reduce soil water storage in alpine grasslands. C1 [Guo, Xiaowei; Dai, Licong; Li, Qian; Qian, Dawen; Cao, Guangmin; Zhou, Huakun; Du, Yangong] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Guo, Xiaowei; Li, Qian; Qian, Dawen; Cao, Guangmin; Zhou, Huakun; Du, Yangong] Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810008, Peoples R China. [Dai, Licong] Univ Chinese Acad Sci, Coll Resource & Environm, Beijing 100000, Peoples R China. RP Du, YG (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China.; Du, YG (通讯作者)，Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810008, Peoples R China. EM guoxw@nwipb.cas.cn; g12004242553@163.com; 18697190176@163.com; dwqian@nwipb.cas.cn; caogm@nwipb.cas.cn; hkzhou@nwipb.cas.cn; ygdu@nwipb.cas.cn TC 10 Z9 12 PD MAR 2 PY 2020 VL 12 IS 6 AR 2523 DI 10.3390/su12062523 UT WOS:000523751400370 DA 2023-03-23 ER PT J AU Luo, LH Duan, QT Wang, LX Zhao, WZ Zhuang, YL AF Luo, Lihui Duan, Quntao Wang, Lixin Zhao, Wenzhi Zhuang, Yanli TI Increased human pressures on the alpine ecosystem along the Qinghai-Tibet Railway SO REGIONAL ENVIRONMENTAL CHANGE DT Article AB Construction of the Qinghai-Tibet Railway (QTR) increased the links between inland China and the Qinghai-Tibet Plateau (QTP). The QTR accelerated surrounding tourism, boosted the local economy and led to rapid development of livestock raising. To assess how distance from the railway and different regions has influenced the impact of the QTR on the alpine ecosystem, human footprint maps were produced to indicate human pressures, and the normalized difference vegetation index (NDVI), an index of vegetation greenness, was used to characterize the growth of alpine vegetation. The construction and operation of the QTR have increased human pressures, while the establishment of nature reserves has effectively reduced human pressures. The QTR contributes significantly to the increased human pressures in the Tibetan region compared with the Qinghai region and exerts negative impacts on alpine vegetation. Although the warmer and wetter climate trend has proven beneficial in enhancing alpine vegetation greenness, the declining trend of alpine vegetation has been stronger in regions with more intensive human pressures, especially in the grazing areas and the tourist areas around Lhasa. These results suggest that the impact of the QTR on alpine vegetation in Tibet is greater than that in Qinghai and that the spatial extent of the indirect impact of the QTR in Tibet is confined to approximately 30 km from the railway. These results will provide guidance and a theoretical basis for the protection of the alpine environment on the QTP under intensified anthropogenic influence. C1 [Luo, Lihui; Duan, Quntao; Zhao, Wenzhi; Zhuang, Yanli] Chinese Acad Sci, Linze Inland River Basin Res Stn, Key Lab Inland River Basin Ecohydrol, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. [Luo, Lihui; Duan, Quntao; Zhao, Wenzhi; Zhuang, Yanli] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Lixin; Zhuang, Yanli] IUPUI, Dept Earth Sci, Indianapolis, IN 46202 USA. RP Luo, LH (通讯作者)，Chinese Acad Sci, Linze Inland River Basin Res Stn, Key Lab Inland River Basin Ecohydrol, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China.; Luo, LH (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM luolh@lzb.ac.cn; duanqt@lzb.ac.cn; lxwang@iupui.edu; zhaowzh@lzb.ac.cn; zhuangyl@lzb.ac.cn TC 12 Z9 15 PD MAR 2 PY 2020 VL 20 IS 1 AR 33 DI 10.1007/s10113-020-01616-7 UT WOS:000519060700001 DA 2023-03-23 ER PT J AU Mou, XM Yu, YW Li, XG Degen, AA AF Mou, Xiao Ming Yu, Ying Wen Li, Xiao Gang Degen, A. Allan TI Presence frequency of plant species can predict spatial patterns of the species in small patches on the Qinghai-Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Patchiness is an important feature in grassland ecosystems, but the distribution pattern of plant species in small patches on the Qinghai-Tibetan Plateau (QTP) is largely unknown. We questioned: (1) whether the power law can be applied to determine the spatial pattern of plant species in small patches; and (2) how species frequency (dominant, companion and rare) affects the spatial heterogeneity of small patches on the QTP? The power law was used to examine the spatial pattern of plant species and examine the relationship between the plant species presence frequency and spatial pattern in three types of small patches (Cyperaceae, Polygonaceae and Compositae), each with three spatial extents according to the size of the area (scale 1: 0.6-0.9 m(2), scale 2: 3.0-3.8 m(2) and scale 3: 6.5-8.8 m(2)) on the QTP. Plant species in patches showed an aggregated distribution and the spatial heterogeneity index differed among species. The spatial heterogeneities of Cyperaceae and Polygonaceae patches were influenced strongly by dominant and companion plant species, while the Compositae patch was influenced by dominant and rare species. The Compositae patches exhibited a lower species diversity and higher spatial heterogeneity index than the other patches, and the extensive distribution of Compositae community can be linked to degradation processes in the alpine meadow. We concluded that the spatial pattern of plant species and the heterogeneity index for small patches could be determined by the species presence frequency on the QTP. (C) 2019 The Authors. Published by Elsevier B.V. C1 [Mou, Xiao Ming; Yu, Ying Wen; Li, Xiao Gang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat,Minist Ag, Lanzhou 730020, Peoples R China. [Degen, A. Allan] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, IL-84105 Beer Sheva, Israel. RP Yu, YW (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat,Minist Ag, Lanzhou 730020, Peoples R China. EM mouxm@lzu.edu.cn; yuyw@lzu.edu.cn; lixiaogang@lzu.edu.cn; degen@bgu.ac.il TC 7 Z9 7 PD MAR PY 2020 VL 21 AR e00888 DI 10.1016/j.gecco.2019.e00888 UT WOS:000517814100086 DA 2023-03-23 ER PT J AU Song, MH Chen, J Xu, XL Li, YK Gao, JQ OuYang, H AF Song, Ming-Hua Chen, Jin Xu, Xing-Liang Li, Yi-Kang Gao, Jun-Qin OuYang, Hua TI Grazing Offsets Nitrogen Enrichment Effects on Species Richness by Promoting the Random Colonization of Local Species in an Alpine Grassland SO ECOSYSTEMS DT Article AB Nitrogen (N)-induced declines in species richness can be offset by grazing via the suppression of dominant species to increase ground-level light. However, it is not known whether grazing-mediated locally colonized species correspond to N-induced locally extinct species with regard to taxonomy or traits. Data from 11 years of N addition and winter grazing experiments were analyzed to assess species richness dynamics at community and functional group levels. Regarding N treatments, enclosure and N addition were performed during the first 7 years and were then followed by winter grazing with continuous N addition during the next 4 years. Additionally, all treatments were used to compare N-induced local species extinction and grazing-mediated local species colonization. Then, traits of N-induced locally extinct species and grazing-mediated locally colonized species were further correlated with plant traits. We found that N addition induced a decline in plant species richness as a result of both random and non-random species losses. The lost species were closely associated with traits, including low height, non-clonality, low special leaf area (SLA), and low leaf N concentrations, which are relevant to light capture capacity. In contrast, grazing promoted the random colonization of local rare species, thus offsetting the N-induced decline of species richness. However, non-randomly lost species were not rescued by grazing. Grazing-mediated locally colonized species were generally characterized by high leaf carbon (C) concentrations, SLA, and seed mass. Our study provides experimental evidence indicating although grazing offsets N-induced species reduction, shifts in species composition and traits could cause a divergence in ecosystem function facing anthropogenic alterations to nutrient cycles and grazing. C1 [Song, Ming-Hua; Chen, Jin; Xu, Xing-Liang; OuYang, Hua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, A11 Datun Rd, Beijing 100101, Peoples R China. [Chen, Jin] Univ Chinese Acad Sci, Yuquan Rd 35, Beijing 100083, Peoples R China. [Song, Ming-Hua; Li, Yi-Kang] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, 59 Xiguan Dajie, Xining 810008, Peoples R China. [Gao, Jun-Qin] Beijing Forestry Univ, Sch Nat Conservat, Qinghua East Rd 35, Beijing 100083, Peoples R China. RP Song, MH; Xu, XL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, A11 Datun Rd, Beijing 100101, Peoples R China.; Song, MH (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, 59 Xiguan Dajie, Xining 810008, Peoples R China. EM songmh@igsnrr.ac.cn; xuxl@igsnrr.ac.cn TC 5 Z9 5 PD MAR PY 2020 VL 23 IS 2 BP 278 EP 291 DI 10.1007/s10021-019-00403-8 UT WOS:000520408600004 DA 2023-03-23 ER PT J AU Xiao, X Zhang, T Angerer, JP Hou, FJ AF Xiao, Xiang Zhang, Tao Angerer, Jay Peter Hou, Fujiang TI Grazing Seasons and Stocking Rates Affects the Relationship between Herbage Traits of Alpine Meadow and Grazing Behaviors of Tibetan Sheep in the Qinghai-Tibetan Plateau SO ANIMALS DT Article AB Simple Summary The relationship between vegetation and grazing behavior of Tibetan sheep on the Qinghai-Tibetan Plateau (QTP) remains a major concern for pursuing the sustainable grazing management of grassland. Grazing behavior is the daily activity of grazing livestock, which can reflect the growth status of the pasture and the level of grassland health in the local pasture, as well as the nutritional needs of Tibetan sheep. We studied the relationship between the grazing behaviors of Tibetan sheep and the quantity and quality of forage in different seasons and different stocking rates. Our results showed that the grazing behavior of Tibetan sheep was greatly affected by the quantity and nutritional quality of the forage. These results may be helpful for local herders to evaluate the nutritional status of forage and condition of grassland degradation, so that appropriate measures can be taken to protect local pastures in advance. Abstract Under the combined effect of stocking rate and grazing season, it is very significant to ascertain whether there is a quantitative relationship between plant community characteristics, chemical composition of forage, and grazing behaviors of Tibetan sheep to better utilize native pasture in the northeast region of the Qinghai-Tibetan Plateau (QTP). The two consecutive year observation experiments on Tibetan sheep's grazing behavior were conducted to evaluate the above-stated relationships between stocking rates of 8 sheep/ha and 16 sheep/ha stocking rates in the both the warm and cold seasons. The results demonstrated that at 8 sheep/ha or in the warm season, due to better forage quality, Tibetan sheep had higher herbage mass, forage crude protein (CP) concentration, CP intake, dry matter intake (DMI), and interval between feed boluses and total number of steps, as well as lower fiber concentration than that at 16 sheep/ha or in the cold season. Diurnal intake rate and walking velocity while intaking increased as both average daylight ambient temperature and relative humidity rose. Using the CP concentration, acid detergent fiber (ADF) concentration, neutral detergent fiber (NDF) concentration, and forage metabolic energy (ME) to predict grazing behavior yielded the best fit equation for Tibetan sheep. For local herdsmen to sustainably use the alpine meadow, 8 sheep/ha in the warm season should be considered as the better grazing condition for preventing grassland degradation. C1 [Xiao, Xiang; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. [Xiao, Xiang; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730020, Peoples R China. [Xiao, Xiang; Hou, Fujiang] Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China. [Xiao, Xiang; Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. [Zhang, Tao] Guizhou Univ, Inst New Rural Dev, Guiyang 550025, Peoples R China. [Angerer, Jay Peter] Texas A&M AgriLife Res, Blackland Res & Extens Cent, Temple, TX 76502 USA. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China.; Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730020, Peoples R China.; Hou, FJ (通讯作者)，Minist Agr & Rural Affairs, Lanzhou 730020, Peoples R China.; Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. EM xiaox17@lzu.edu.cn; zhangtaoeco@outlook.com; jangerer@brc.tamus.edu; cyhoufj@lzu.edu.cn TC 12 Z9 14 PD MAR PY 2020 VL 10 IS 3 AR 488 DI 10.3390/ani10030488 UT WOS:000529378800121 DA 2023-03-23 ER PT J AU Zhang, Y Zhang, N Yin, JJ Yang, F Zhao, YX Jiang, ZQ Tao, JJ Yan, XB Qiu, YP Guo, H Hu, SJ AF Zhang, Yi Zhang, Nan Yin, Jingjing Yang, Fei Zhao, Yexin Jiang, Zhongquan Tao, Jinjin Yan, Xuebin Qiu, Yunpeng Guo, Hui Hu, Shuijin TI Combination of warming and N inputs increases the temperature sensitivity of soil N2O emission in a Tibetan alpine meadow SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Many high-elevation alpine ecosystems have been experiencing significant increases in air temperature and, to a lesser extent, nitrogen (N) deposition. These changes may affect N-cycling microbes and enhance emissions of nitrous oxide (N2O, a potent greenhouse gas) from soil. However, few studies have investigated whether and how the resulting changes in N-cycling microbes may affect the temperature sensitivity (Q(10)) of N2O emission and in turn feed back to N2O emissions. We conducted two incubation experiments to examine N2O emissions and their temperature sensitivities in soils that had experienced 3-yr field treatments of warming, N inputs and their combination in a Tibetan alpine meadow. Our results showed that neither N inputs nor warming alone affected the rate or Q(10) of soil N2O emission, but combining the two significantly increased both parameters. Also, combined N and warming significantly increased the abundance of ammonia-oxidizing bacteria (AOB), corresponding with high soil N2O emission. In addition, N2O emission from nitrification accounted for 60-80% of total emissions in all soils, indicating that nitrifying microbes dominated the N2O production and its temperature sensitivity. Using random forest (RF) and structural equation model (SEM) analyses, we further evaluated the effects of various soil characteristics on soil N2O emissions and Q(10). We identified soil moisture, pH, N mineralization and AOB abundance as the main predictors of the Q(10) of N2O emissions. Together, these findings suggest that alterations in soil moisture, pH and ammonia-oxidizing bacteria induced by long-term N inputs and warming may increase temperature sensitivity of soil N2O emissions, leading to a positive climate feedback in this high-altitude alpine ecosystem. (C) 2019 Elsevier B.V. All rights reserved. C1 [Zhang, Yi; Zhang, Nan; Yin, Jingjing; Yang, Fei; Zhao, Yexin; Jiang, Zhongquan; Tao, Jinjin; Yan, Xuebin; Qiu, Yunpeng; Guo, Hui; Hu, Shuijin] Nanjing Agr Univ, Coll Resources & Environm Sci, Ecosyst Ecol Lab, Nanjing 210095, Jiangsu, Peoples R China. [Hu, Shuijin] North Carolina State Univ, Dept Entomol & Plant Pathol, Raleigh, NC 27695 USA. RP Hu, SJ (通讯作者)，North Carolina State Univ, Dept Entomol & Plant Pathol, Raleigh, NC 27695 USA.; Zhang, Y (通讯作者)，Nanjing Agr Univ, Coll Resources & Environm Sci, Nanjing 210095, Jiangsu, Peoples R China. EM zhangyi2016@njau.edu.cn; shuijin_hu@ncsu.edu TC 12 Z9 13 PD FEB 20 PY 2020 VL 704 AR 135450 DI 10.1016/j.scitotenv.2019.135450 UT WOS:000504672800027 DA 2023-03-23 ER PT J AU Huang, XM Song, ZW van Groenigen, KJ Xu, ZY Huang, B Zhang, Y Hang, XN Tan, SH Zhang, DG Zhang, WJ AF Huang, Xiaomin Song, Zhenwei van Groenigen, Kees Jan Xu, Zhiyu Huang, Bo Zhang, Yi Hang, Xiaoning Tan, Shuhao Zhang, Degang Zhang, Weijian TI Grassland conversion along a climate gradient in northwest China: Implications for soil carbon and nutrients SO SOIL USE AND MANAGEMENT DT Article AB Soil organic carbon (SOC) stocks and nutrient availability are key indicators of soil quality, and both can be influenced by land-use change. However, it is still unclear whether the impact of land-use change on SOC and nutrient stocks differs between ecoregions. Grasslands near the northeast border of the Qinghai-Tibetan Plateau (QTP) occur across several ecoregions that have recently been subjected to substantial land-use change. Based on long-term land-use history, we conducted a field investigation comparing soil C and nutrient stocks between natural grassland (NGL) and three types of converted grassland (agricultural grassland, AGL; farmland, FL; and abandoned farmland, AFL) in three ecoregions along a climate gradient: alpine meadow, temperate steppe and temperate desert. Compared with NGL, soil C stocks in converted grasslands were 22%-30% lower in the alpine meadow, but 60-82% higher in the temperate steppe and 6%-76% higher in the temperate desert. Converted grasslands also contained higher stocks of available nitrogen and phosphorus than NGL in the temperate steppe and desert. Soils (0-40 cm) in NGL contained 14.8 +/- 0.1 kg C m(-2) in alpine meadow, 6.7 +/- 0.6 kg C m(-2) in temperate steppe and 1.7 +/- 0.3 kg C m(-2) in temperate desert. Together, our results indicate that the responses of soil C and nutrients to grassland conversion differed between ecoregions. Thus, to optimize soil C sequestration rates and overall soil quality, we suggest that land-use policies in this area should take into account local environmental conditions. C1 [Huang, Xiaomin; Zhang, Weijian] Nanjing Agr Univ, Coll Agr, Nanjing 210095, Peoples R China. [Huang, Xiaomin; Song, Zhenwei; Zhang, Weijian] Chinese Acad Agr Sci, Inst Crop Sci, Beijing, Peoples R China. [Huang, Xiaomin; van Groenigen, Kees Jan] Univ Exeter, Coll Climate & Environm Sci, Exeter, Devon, England. [Xu, Zhiyu; Huang, Bo] Minist Agr, Rural Energy & Environm Agcy, Beijing, Peoples R China. [Zhang, Yi] Nanjing Agr Univ, Coll Resources & Environm Sci, Nanjing, Peoples R China. [Hang, Xiaoning] Chongqing Acad Agr Sci, Chongqing, Peoples R China. [Tan, Shuhao] Renmin Univ China, Beijing, Peoples R China. [Zhang, Degang] Gansu Agr Univ, Lanzhou, Peoples R China. RP Zhang, WJ (通讯作者)，Nanjing Agr Univ, Coll Agr, Nanjing 210095, Peoples R China. EM zwj@njau.edu.cn TC 4 Z9 4 PD JUL PY 2020 VL 36 IS 3 BP 410 EP 419 DI 10.1111/sum.12574 EA FEB 2020 UT WOS:000510789700001 DA 2023-03-23 ER PT J AU Zhang, R Degen, AA Bai, YF Zhang, T Wang, XM Zhao, XY Shang, ZH AF Zhang, Rui Degen, A. Allan Bai, Yanfu Zhang, Tao Wang, Ximing Zhao, Xueyong Shang, Zhanhuan TI The forb, Ajania tenuifolia, uses soil nitrogen efficiently, allowing it to be dominant over sedges and Graminae in extremely degraded grasslands: Implications for grassland restoration and development on the Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Plant growth is mainly N-limited in the alpine grasslands because of slow mineralization of soil organic matter due to low air temperature. Different plant species dominate in soils of different N concentrations. For example, more forbs occur in severely degraded alpine meadows than do sedges and Gramineae. We hypothesized that a more efficient uptake of low soil N by forbs than by sedges and Gramineae was the mechanism that allowed forbs to dominate. The amount and rate of soil N uptake and N allocation were determined in seven dominant alpine plant species using N-15 isotope tracer. The plants, which included one forb, Ajania tenuifolia, three sedges, Kobresia humilis, Carex scabrirostris, and Carex enervis, and three Gramineae, Elymus nutans, Festuca sinensis, and Stipa purpurea, were maintained in pots with four different N concentrations (0, 50, 100, and 150 kg ha(-1)). The forb had the highest efficiency of N utilization (N uptake rate, 60.4%) in low N soil concentration, the Gramineae had intermediate efficiencies (27.9-47.9%), and the sedges had the lowest efficiencies (5.2-34.9%), and, consequently, our hypothesis was supported. N utilization of the seven species decreased with an increase in soil N concentration, from 32.1% at N50 to 18.0% at N150, which indicated that soil N uptake by plants was affected by soil N concentration. The mechanism used by forbs to be the dominant species in severely degraded alpine meadows was a more efficient utilization of soil N than Gramineae and sedges in conditions of low soil N. We concluded that plant species have different efficiencies in soil N uptake and utilization, which allow them to adapt and survive in habitats of different soil nutrition levels. These results implied that forbs should be reduced, and that Gramineae and sedges should be planted and N be added during the restoration and development of severely degraded grasslands on the Tibetan plateau when the soil N content is low. C1 [Zhang, Rui; Bai, Yanfu; Zhang, Tao; Wang, Ximing; Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Zhang, Rui; Zhao, Xueyong] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Naiman Desertificat Res Stn, Urat Desert Grassland Res Stn, Lanzhou, Peoples R China. [Degen, A. Allan] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, Beer Sheva, Israel. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. EM shangzhh@lzu.edu.cn TC 7 Z9 8 PD JUN PY 2020 VL 31 IS 10 BP 1265 EP 1276 DI 10.1002/ldr.3555 EA FEB 2020 UT WOS:000510781200001 DA 2023-03-23 ER PT J AU Chen, YM Liu, Y Zhang, J Yang, WQ Deng, CC He, RL AF Chen, Yamei Liu, Yang Zhang, Jian Yang, Wanqin Deng, Changchun He, Runlian TI Cumulative cellulolytic enzyme activities and initial litter quality in prediction of cellulose degradation in an alpine meadow of the eastern Tibetan Plateau SO JOURNAL OF PLANT ECOLOGY DT Article AB Aims Plant litter decomposition is a key ecosystem process that determines carbon and nutrient cycling in terrestrial ecosystems. As a main component of litter, cellulose is a vital energy source for the microbes associated with litter decomposition. The important role of cellulolytic enzymes in litter cellulose degradation is well understood, but seasonal patterns of cellulose degradation and whether cumulative enzyme activities and litter quality forecast cellulose degradation in an alpine meadow remain elusive, which limits our understanding of cellulose degradation in herbaceous plant litter. Methods A two-year field litterbag experiment involving three dominant species (Ajuga ovalifolia, Festuca wallichanica, and Pedicularis roylei) was conducted in an alpine meadow of the eastern Tibetan Plateau to explore the seasonal patterns of cellulose degradation and how cumulative cellulolytic enzyme activities and initial litter quality impact cellulose degradation. Important findings Our study demonstrates that cellulose degraded rapidly and exceeded 50% during the first year, which mainly occurred in the first growing season (31.9%-43.3%). At two years of decomposition, cellulose degradation was driven by cumulative endoglucanase (R-2 = 0.70), cumulative cellobiohydrolase (R-2 = 0.59) and cumulative 1,4-beta-glucosidase (R-2 = 0.57). In addition, the concentrations of cellulose, dissolved organic carbon, total phenol, lignin and lignin/N accounted for 52%-78% of the variation in cellulose degradation during the two years of decomposition. The best model for predicting cellulose degradation was the initial cellulose concentration (R-2 = 0.78). The enzymatic efficiencies and the allocation of cellulolytic enzyme activities were different among species. The cellulolytic enzyme efficiencies were higher in the litter of F. wallichanica with relatively lower quality. For the complete cellulose degradation of the leaf litter, A. ovalifolia and F. wallichanica required 4-fold and 6.7-fold more endoglucanase activity, 3-fold and 4.5-fold more cellobiohydrolase activity and 1.2-fold and 1.4-fold more 1,4-beta-glucosidase activity, respectively, than those required by P. roylei. Our results demonstrated that although microbial activity and litter quality both have significant impacts on cellulose degradation in an alpine meadow, using cellulose concentration to predict cellulose degradation is a good way to simplify the model of cellulose degradation and C cycling during litter decomposition. C1 [Chen, Yamei; Liu, Yang; Zhang, Jian; Yang, Wanqin; Deng, Changchun; He, Runlian] Sichuan Agr Univ, Inst Ecol & Forestry, Key Lab Ecol Forestry Engn, Long Term Res Stn Alpine Forest Ecosyst, 211 Huimin Rd, Chengdu 611130, Peoples R China. RP Liu, Y; Zhang, J (通讯作者)，Sichuan Agr Univ, Inst Ecol & Forestry, Key Lab Ecol Forestry Engn, Long Term Res Stn Alpine Forest Ecosyst, 211 Huimin Rd, Chengdu 611130, Peoples R China. EM sicauliuyang@163.com; sicauzhangjian@163.com TC 3 Z9 4 PD FEB PY 2020 VL 13 IS 1 BP 51 EP 58 DI 10.1093/jpe/rtz044 UT WOS:000529932500008 DA 2023-03-23 ER PT J AU Fayiah, M Dong, SK Khomera, SW Rehman, SAU Yang, MY Xiao, JN AF Fayiah, Moses Dong, ShiKui Khomera, Sphiwe Wezzie Rehman, Syed Aziz Ur Yang, Mingyue Xiao, Jiannan TI Status and Challenges of Qinghai-Tibet Plateau's Grasslands: An Analysis of Causes, Mitigation Measures, and Way Forward SO SUSTAINABILITY DT Article AB Grassland ecosystems on the Qinghai-Tibet Plateau (QTP) provide numerous ecosystem services and functions to both local communities and the populations living downstream through the provision of water, habitat, food, herbal medicines, and shelter. This review examined the current ecological status, degradation causes, and impacts of the various grassland degradation mitigation measures employed and their effects on grassland health and growth in the QTP. Our findings revealed that QTP grasslands are continually being degraded as a result of complex biotic and abiotic drivers and processes. The biotic and abiotic actions have resulted in soil erosion, plant biomass loss, soil organic carbon loss, a reduction in grazing and carrying capacity, the emergence of pioneer plant species, loss of soil nutrients, and an increase in soil pH. A combination of factors such as overgrazing, land-use changes, invasive species encroachment, mining activities, rodent burrowing activities, road and dam constructions, tourism, migration, urbanization, and climate change have caused the degradation of grasslands on the QTP. A conceptual framework on the way forward in tackling grassland degradation on the QTP is presented together with other appropriate measures needed to amicably combat grassland degradation on the QTP. It is recommended that a comprehensive and detailed survey be carried out across the QTP to determine the percentage of degraded grasslands and hence, support a sound policy intervention. C1 [Fayiah, Moses; Dong, ShiKui; Yang, Mingyue; Xiao, Jiannan] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Fayiah, Moses] Njala Univ, Sch Nat Resources Management, Dept Forestry, Njala 232, Sierra Leone. [Dong, ShiKui] Cornell Univ, Dept Nat Resources, Fernow Hall, Ithaca, NY 14853 USA. [Khomera, Sphiwe Wezzie] Beijing Normal Univ, Fac Educ, Dept Comparat Educ, Beijing 100875, Peoples R China. [Rehman, Syed Aziz Ur] Univ Vet & Anim Sci, Dept Environm Sci, Lahore 54000, Pakistan. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China.; Dong, SK (通讯作者)，Cornell Univ, Dept Nat Resources, Fernow Hall, Ithaca, NY 14853 USA. EM moses.fayiah@yahoo.co.uk; dsk03037@bnu.edu.cn; swkhomera@gmail.com; syed.aziz@uvas.edu.pk; yueyuemuseum@163.com; xiaojiannan168@163.com TC 26 Z9 29 PD FEB PY 2020 VL 12 IS 3 AR 1099 DI 10.3390/su12031099 UT WOS:000524899601042 DA 2023-03-23 ER PT J AU Hou, MJ Ge, J Gao, JL Meng, BP Li, YC Yin, JP Liu, J Feng, QS Liang, TG AF Hou, Mengjing Ge, Jing Gao, Jinlong Meng, Baoping Li, Yuanchun Yin, Jianpeng Liu, Jie Feng, Qisheng Liang, Tiangang TI Ecological Risk Assessment and Impact Factor Analysis of Alpine Wetland Ecosystem Based on LUCC and Boosted Regression Tree on the Zoige Plateau, China SO REMOTE SENSING DT Article AB The Zoige Plateau is typical of alpine wetland ecosystems worldwide, which play a key role in regulating global climate and ecological balance. Due to the influence of global climate change and intense human activities, the stability and sustainability of the ecosystems associated with the alpine marsh wetlands are facing enormous threats. It is important to establish a precise risk assessment method to evaluate the risks to alpine wetlands ecosystems, and then to understand the influencing factors of ecological risk. However, the multi-index evaluation method of ecological risk in the Zoige region is overly focused on marsh wetlands, and the smallest units of assessment are relatively large. Although recently developed landscape ecological risk assessment (ERA) methods can address the above limitations, the final directionality of the evaluation results is not clear. In this work, we used the landscape ERA method based on land use and land cover changes (LUCC) to evaluate the ecological risks to an alpine wetland ecosystem from a spatial pixel scale (5 km x 5 km). Furthermore, the boosted regression tree (BRT) model was adopted to quantitatively analyze the impact factors of ecological risk. The results show the following: (1) From 1990 to 2016, the land use and land cover (LULC) types in the study area changed markedly. In particular, the deep marshes and aeolian sediments, and whereas construction land areas changed dramatically, the alpine grassland changed relatively slowly. (2) The ecological risk in the study area increased and was dominated by regions with higher and moderate risk levels. Meanwhile, these areas showed notable spatio-temporal changes, significant spatial correlation, and a high degree of spatial aggregation. (3) The topographic distribution, climate changes and human activities influenced the stability of the study area. Elevation (23.4%) was the most important factor for ecological risk, followed by temperature (16.2%). Precipitation and GDP were also seen to be adverse factors affecting ecological risk, at levels of 13.0% and 12.1%, respectively. The aim of this study was to provide more precise and specific support for defining conservation objectives, and ecological management in alpine wetland ecosystems. C1 [Hou, Mengjing; Ge, Jing; Gao, Jinlong; Li, Yuanchun; Yin, Jianpeng; Liu, Jie; Feng, Qisheng; Liang, Tiangang] Lanzhou Univ, Minist Educ,Minist Agr & Rural Affairs, Coll Pastoral Agr Sci & Technol,State Key Lab Gra, Engn Res Ctr Grassland Ind,Key Lab Grassland Live, Lanzhou 730000, Peoples R China. [Meng, Baoping] Nantong Univ, Inst Fragile Ecoenvironm, 999 Tongjing Rd, Nantong 226007, Peoples R China. RP Liang, TG (通讯作者)，Lanzhou Univ, Minist Educ,Minist Agr & Rural Affairs, Coll Pastoral Agr Sci & Technol,State Key Lab Gra, Engn Res Ctr Grassland Ind,Key Lab Grassland Live, Lanzhou 730000, Peoples R China. EM houmj17@lzu.edu.cn; gej12@lzu.edu.cn; gaoj116@lzu.edu.cn; mengbp09@lzu.edu.cn; liych18@lzu.edu.cn; yinjp2013@lzu.edu.cn; liuj14@lzu.edu.cn; fengqsh@lzu.edu.cn; tgliang@lzu.edu.cn TC 37 Z9 39 PD FEB PY 2020 VL 12 IS 3 AR 368 DI 10.3390/rs12030368 UT WOS:000515393800027 DA 2023-03-23 ER PT J AU Su, JH Ji, WH Li, H Yao, T Wang, JF Nan, ZB AF Su, Junhu Ji, Weihong Li, Huan Yao, Tuo Wang, Jianfeng Nan, Zhibiao TI Zokor disturbances indicated positive soil microbial responses with carbon cycle and mineral encrustation in alpine grassland SO ECOLOGICAL ENGINEERING DT Article AB The alpine grassland is a fragile ecosystem sensitive to human disturbance; the Qinghai-Tibetan Plateau alpine grassland is an example with large areas that are currently suffering from degradation. Although subterranean mammals (e.g., the plateau zokor, Eospalax baileyi) are thought to contribute to grassland soil and plant degradation, they are native species and play positive roles in the alpine ecosystem as ecosystem engineers. However, little is known about their effect on soil microbial communities. Using Illumina sequencing of the 16S rRNA gene and the internal transcribed spacer 2 (ITS2) regions, we compared soil prokaryotic and fungal community composition and diversity in areas disturbed by plateau zokors during the grassland recovery process. We found an increase in the number of observed operational taxonomic units (OTUs) of soil prokaryotic and fungal microbes, while the community structure of the microbes became significantly divergent. Soil properties, plant cover, and aboveground biomass explained the majority of the changes in microbial communities, suggesting that the changes in soil and plant characteristics mainly regulate the response of soil microbes to zokor disturbance in alpine grasslands. Zokor disturbances result in positive soil microbial responses in phyla with carbon cycle and mineral encrustation associations, suggesting a positive role for soil microbial community functions. Our findings provide novel evidence that zokors are important ecosystem engineers essential for alpine ecosystem functions. C1 [Su, Junhu; Yao, Tuo] Gansu Agr Univ, Minist Educ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Lanzhou 730070, Peoples R China. [Su, Junhu; Ji, Weihong] Gansu Agr Univ, Massey Univ, Res Ctr Grassland Biodivers, Lanzhou 730070, Peoples R China. [Ji, Weihong] Massey Univ, Sch Nat & Computat Sci, North Shore Mail Ctr, Private Bag 102 904, Auckland 0632, New Zealand. [Li, Huan] Lanzhou Univ, Sch Publ Hlth, Inst Occupat Hlth & Environm Hlth, Lanzhou 730020, Peoples R China. [Wang, Jianfeng; Nan, Zhibiao] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. RP Su, JH (通讯作者)，Gansu Agr Univ, Minist Educ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Lanzhou 730070, Peoples R China. EM sujh@gsau.edu.cn TC 8 Z9 10 PD FEB 1 PY 2020 VL 144 AR 105702 DI 10.1016/j.ecoleng.2019.105702 UT WOS:000509459800004 DA 2023-03-23 ER PT J AU Wang, SR Guo, LL He, B Lyu, YL Li, TW AF Wang, Shuren Guo, Lanlan He, Bin Lyu, Yanli Li, Tiewei TI The stability of Qinghai-Tibet Plateau ecosystem to climate change SO PHYSICS AND CHEMISTRY OF THE EARTH DT Article AB Climate change and simultaneous increases in extreme events have significant impacts on the structure and function of the global ecosystem. The response of the ecosystem on the Qinghai-Tibet Plateau (QTP) to climate change has drawn increasing attention for its prominent elevation. In this study, resistance and resilience were selected as two stability indicators of ecosystems to analyze the response of the QTP ecosystem to climate change over the past 34 years. We explored the main climate drivers that affect vegetation change, and predicted the stability of the ecosystem in the future. The results showed that the coniferous and Hylaea coniferous and hylaea forests of the QTP had high resilience, whereas the steppe and meadow had poor resilience. Shrubs and coniferous and hylaea coniferous and hylaea forests were with less resistance to climate change, whereas steppe and meadow showed more resistance to climate change. Temperature (TEMP) was the driving factor that affected the stability of steppe and meadow; however, precipitation (PRE) had a greater impact on stability of coniferous and hylaea forests and shrubs. Based on the CMIP5 results, TEMP and PRE on the QTP will significantly increase (p < 0.01) in the next 85 years, and 50.48% of the QTP will become more suitable for vegetation growth, mainly distributing in the southern meadow, part of the Hylaea, and areas bordering the southeastern coniferous and hylaea forests and shrubs. However, the ecosystem degradation might occurr in the central and eastern meadow regions. C1 [Wang, Shuren; Guo, Lanlan] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Wang, Shuren; Guo, Lanlan; Lyu, Yanli; Li, Tiewei] Beijing Normal Univ, Fac Geog Sci, Beijing 100875, Peoples R China. [He, Bin] Beijing Normal Univ, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China. RP Guo, LL (通讯作者)，Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. EM guolanlan@bnu.edu.cn TC 19 Z9 20 PD FEB PY 2020 VL 115 AR 102827 DI 10.1016/j.pce.2019.102827 UT WOS:000517961300022 DA 2023-03-23 ER PT J AU Zong, N Song, MH Zhao, GS Shi, PL AF Zong, Ning Song, Minghua Zhao, Guangshuai Shi, Peili TI Nitrogen economy of alpine plants on the north Tibetan Plateau: Nitrogen conservation by resorption rather than open sources through biological symbiotic fixation SO ECOLOGY AND EVOLUTION DT Article AB Nitrogen (N) is one of the most important factors limiting plant productivity, and N fixation by legume species is an important source of N input into ecosystems. Meanwhile, N resorption from senescent plant tissues conserves nutrients taken up in the current season, which may alleviate ecosystem N limitation. N fixation was assessed by the N-15 dilution technique in four types of alpine grasslands along the precipitation and soil nutrient gradients. The N resorption efficiency (NRE) was also measured in these alpine grasslands. The aboveground biomass in the alpine meadow was 4-6 times higher than in the alpine meadow steppe, alpine steppe, and alpine desert steppe. However, the proportion of legume species to community biomass in the alpine steppe and the alpine desert steppe was significantly higher than the proportion in the alpine meadow. N fixation by the legume plants in the alpine meadow was 0.236 g N/m(2), which was significantly higher than N fixation in other alpine grasslands (0.041 to 0.089 g N/m(2)). The NRE in the alpine meadows was lower than in the other three alpine grasslands. Both the aboveground biomass and N fixation of the legume plants showed decreasing trends with the decline of precipitation and soil N gradients from east to west, while the NRE of alpine plants showed increasing trends along the gradients, which indicates that alpine plants enhance the NRE to adapt to the increasing droughts and nutrient-poor environments. The opposite trends of N fixation and NRE along the precipitation and soil nutrient gradients indicate that alpine plants adapt to precipitation and soil nutrient limitation by promoting NRE (conservative nutrient use by alpine plants) rather than biological N fixation (open sources by legume plants) on the north Tibetan Plateau. C1 [Zong, Ning; Song, Minghua; Shi, Peili] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing, Peoples R China. [Zhao, Guangshuai] Natl Forestry & Grassland Adm, China Natl Forestry Grassland Econ & Dev Res Ctr, Beijing, Peoples R China. [Shi, Peili] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. RP Zong, N; Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, 11A,Datun Rd, Beijing 100101, Peoples R China. EM zongning@igsnrr.ac.cn; shipl@igsnrr.ac.cn TC 7 Z9 8 PD FEB PY 2020 VL 10 IS 4 BP 2051 EP 2061 DI 10.1002/ece3.6038 EA JAN 2020 UT WOS:000509469900001 DA 2023-03-23 ER PT J AU Ji, L Qin, Y Jimoh, SO Hou, XY Zhang, N Gan, YM Luo, YJ AF Ji, Lei Qin, Yan Jimoh, Saheed Olaide Hou, Xiangyang Zhang, Na Gan, Youmin Luo, Yuanjia TI Impacts of livestock grazing on vegetation characteristics and soil chemical properties of alpine meadows in the eastern Qinghai-Tibetan Plateau SO ECOSCIENCE DT Article AB Livestock grazing is one of the significant causes of land degradation. However, the effect of contrasting grazing intensities on soil properties and vegetation in the southeastern Qinghai-Tibetan Plateau (QTP) is poorly understood. We studied the impact of light grazing (LG), moderate grazing (MG), heavy grazing (HG) and no grazing (NG) on vegetation characteristics and the chemical properties of soil samples taken at 0-10 cm, 10-20 cm and 20-30 cm layers from the designated grazing treatments. A total of 42 species representing 32 genera and 16 families were identified. Our result shows that HG significantly reduced total aboveground biomass, vegetation cover, canopy average height, but increased unpalatable aboveground biomass. Soil organic matter declined with increasing grazing intensity and respectively decreased to 64.51%, 65.38% and 82.40% for LG, MG and HG compared to the NG treatment and soil carbon storage exhibited a similar pattern. Soil total nitrogen and phosphorus contents decreased with increasing soil depth, while soil total potassium was not affected by grazing across soil depths. We conclude that 1 yak would have a more severe impact than 3 sheep units on the vegetation community and soil characteristics of alpine meadows in the southeastern QTP. C1 [Ji, Lei; Qin, Yan; Jimoh, Saheed Olaide; Hou, Xiangyang; Zhang, Na] Chinese Acad Agr Sci, Minist Agr, Inst Grassland Res, Key Lab Grassland Ecol & Restorat, 120 East Wulanchabu St, Hohhot 010010, Peoples R China. [Ji, Lei] Inner Mongolia Univ, Sch Ecol & Environm, Hohhot, Peoples R China. [Gan, Youmin; Luo, Yuanjia] Sichuan Agr Univ, Dept Grassland Sci Anim Sci & Technol, Yaan, Sichuan, Peoples R China. RP Ji, L (通讯作者)，Chinese Acad Agr Sci, Minist Agr, Inst Grassland Res, Key Lab Grassland Ecol & Restorat, 120 East Wulanchabu St, Hohhot 010010, Peoples R China. EM jilei-2000@163.com TC 8 Z9 8 PD APR 2 PY 2020 VL 27 IS 2 BP 107 EP 118 DI 10.1080/11956860.2019.1710908 EA JAN 2020 UT WOS:000506290200001 DA 2023-03-23 ER PT J AU Zong, N Shi, PL AF Zong, Ning Shi, Peili TI Soil properties rather than plant production strongly impact soil bacterial community diversity along a desertification gradient on the Tibetan Plateau SO GRASSLAND SCIENCE DT Article AB Grassland desertification is an important environmental issue that has detrimental impacts on the sustainable development of grasslands and human residential environments. Soil microbial community structure might dramatically change during desertification processes because microorganisms are one of the major drivers of ecological processes through their interactions with plants and soil. However, knowledge on the driving factors of microbial diversity changes during the desertification process in alpine grasslands is still lacking. Using a spatial sequence instead of a time successional sequence method, five desertification gradients in alpine steppe were chosen to investigate the changes in soil properties, plants and microbial communities during grassland desertification and to determine the factors that drive microbial community changes. Community coverage, species diversity indices and aboveground biomass gradually decreased from potential to severely heavy desertification gradients (HDs), while species richness and belowground biomass showed unimodal patterns (p < .05). Soil water content and total nitrogen showed gradual decreasing trends, while soil bulk density and gravel content showed opposite trends (p < .05). In addition, both the Shannon diversity index and the Chao1 richness index of soil bacteria increased gradually. The structural equation model showed that of the factors, soil total nitrogen (82.3% of total effect) and soil bulk density (41.4% of total effect) were the most important soil factors affecting soil bacterial diversity. However, community aboveground (43.4% of total effect) and belowground production (13.9% of total effect) were not the primary factors affecting soil microbial diversity. This result suggests that soil microbial diversity during grassland desertification is primarily driven by changes in soil properties, and the effects of vegetation composition and production are relatively small. These findings contribute to the mechanistic understanding of soil microbial diversity by linking changes in soil properties and plant production during desertification processes in alpine ecosystems. C1 [Zong, Ning; Shi, Peili] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, 11A,Datun Rd, Beijing 100101, Peoples R China. [Shi, Peili] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. RP Zong, N (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, 11A,Datun Rd, Beijing 100101, Peoples R China. EM zongning@igsnrr.ac.cn TC 7 Z9 10 PD OCT PY 2020 VL 66 IS 4 BP 197 EP 206 DI 10.1111/grs.12269 EA JAN 2020 UT WOS:000505531400001 DA 2023-03-23 ER PT J AU Chen, DD Li, Q He, FQ Chen, X Xu, SX Zhao, XQ Li, JM Liu, LH Zhao, L AF Chen, Dongdong Li, Qi He, Fuquan Chen, Xin Xu, Shixiao Zhao, Xinquan Li, Jingmei Liu, Lihua Zhao, Liang TI Restoration Measures Supported Surface Soil Carbon and Nitrogen Density in Alpine Grassland of Sanjiangyuan Region, China SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES DT Article AB Soil carbon (C) and nitrogen (N) have different responses to different restoration measures. In this paper, surface (0-30 cm) soil C and N densities under different restoration measures in the Sanjiangyuan region were investigated and analyzed. The results showed that although there was no significant difference between rest-grazing (RG) and normal grazing ( NG) grassland, SOCD in RG increased by 10.15%, and total N density (TND) increased by 8.56% in the year of the experiment. Compared with cropland, 8 years after Grain for Green (GFG), SOCD increased by 10.49-19.31%, SICD increased by 22.47-54.20%, and TND increased by 1.3-17.45%. Compared with HTT (extreme degradation-black soil beach), 12 years after planting artificial grassland, SOCD increased by 43.97-77.21%, SICD increased by 89.19-716.22%, and TND increased by 49.16-71.40%. Conclusions: Differences in soil types and climatic zones were responsible for the differences in soil C and N in different regions. Short-term grazing rest in Sanjiangyuan region has a certain effect on soil fertility restoration. Implementing the GFG project in the agro-pastoral ecotone improved soil fertility and, concurrently, moderate disturbance should be carried out on the basis of increasing vegetation diversity. Artificial grassland planting on black soil beach can improve soil quality, and moderate grazing disturbance in winter had the best immobilization effect on SIC, while no disturbance in the whole year was beneficial to the accumulation of organic matter. Both biological and abiotic factors have affected soil C and N content and density, but the degree of the influence varied with geographic location. C1 [Chen, Dongdong; Li, Qi; He, Fuquan; Chen, Xin; Xu, Shixiao; Zhao, Xinquan; Zhao, Liang] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Qinghai, Peoples R China. [Li, Jingmei] Qinghai Acad Social Sci, Xining, Qinghai, Peoples R China. [Liu, Lihua] Qinghai Engn Consulting Ctr, Xining, Qinghai, Peoples R China. [Chen, Xin] Grad Univ Chinese Acad Sci, Beijing, Peoples R China. RP Zhao, XQ (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Qinghai, Peoples R China. EM xqzhao@nwipb.cas.cn; lzhao@nwipb.cas.cn TC 3 Z9 3 PY 2020 VL 29 IS 5 BP 3071 EP 3083 DI 10.15244/pjoes/114417 UT WOS:000534642300009 DA 2023-03-23 ER PT J AU Dong, SK Shang, ZH Gao, JX Boone, RB AF Dong, Shikui Shang, Zhanhuan Gao, Jixi Boone, Randall B. TI Enhancing sustainability of grassland ecosystems through ecological restoration and grazing management in an era of climate change on Qinghai-Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB The grassland ecosystems cover above 60% of Qinghai-Tibetan Plateau (QTP) and provide important ecosystem services and functions at local and regional scales. However, both anthropogenic and non-anthropogenic disturbances are challenging the sustainability of the QTP's grassland ecosystems in the era of global change. In this review paper, we summarized the causes and effects of grassland degradation, restoration practices used on degraded grasslands, impacts of climate change and nitrogen deposition on plants and soils, adaptation strategies to climate changes, impacts of livestock grazing on plants and soils, and sustainable grazing management on the QTP. We believed that the integration of internal drivers of ecosystem fragility with external disturbances such as overgrazing are the major causes of grassland degradations on the QTP. The quantitative evaluation systems for grassland ecosystem health including plant, soil and livestock indicators are theoretically feasible and technically reliable. The major impacts of grassland degradation on the QTP are loss of biodiversity, increased water erosion, reduced carbon sequestration, decrease pastoral productivity and reduced local human well-being. The current restoration practices are mostly revegetation of "Bare Land" severely degraded grasslands using cultivated grasses. Other restoration practices such as grazing fallow and grassland fencing can be applied to restore the lightly or moderately degraded grasslands. We believed that the side effects from soil drying on plant productivity and diversity in manipulative warming experiments could be the main cause of controversial findings about the effects of climate change on plant productivity, diversity, phenology, soil physics, biochemistry and organisms. Many scholars argued the advances and delays in greening-up date, lengthening and shortening of the growth period in the phenological responses of alpine grassland plants to a warming climate. Multiple sources of remote sensing data and diverse interpretive approaches should be applied and ground-based observations and surveys should be performed to improve the accuracy and reliability of model predictions on plant phenology. Inconsistent conclusions of climate change impacts on soil biochemistry and organisms except soil acidification and eutrophication have been widely observed in most manipulated studies of nitrogen deposition. Adaptive strategies should be employed to promote grassland system's sustainability of the QTP. Rotational grazing regime with moderate grazing intensity in the warm season may retain or promote plant height, cover, productivity and biodiversity, improve soil structure, fertility and microbial biomass, enhance carbon and nitrogen storage and reduce greenhouse gas emissions in the alpine grassland ecosystems. C1 [Dong, Shikui] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, Sate Key Lab Grassland Ago Ecosyst, Lanzhou 730000, Gansu, Peoples R China. [Gao, Jixi] Minist Ecol & Environm, Ctr Satellite Applicat Ecol & Environm, Beijing 100094, Peoples R China. [Boone, Randall B.] Colorado State Univ, Dept Ecosyst Sci & Sustainabil, Nat Resource Ecol Lab, Ft Collins, CO 80523 USA. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China.; Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, Sate Key Lab Grassland Ago Ecosyst, Lanzhou 730000, Gansu, Peoples R China. EM dsk03037@bnu.edu.cn; shangzhh@lzu.edu.cn TC 178 Z9 187 PD JAN 1 PY 2020 VL 287 AR 106684 DI 10.1016/j.agee.2019.106684 UT WOS:000500216600006 DA 2023-03-23 ER PT J AU Dong, SK Zhang, J Li, YY Liu, SL Dong, QNM Zhou, HK Yeomans, J Li, Y Li, S Gao, XX AF Dong, Shikui Zhang, Jing Li, Yuanyuan Liu, Shiliang Dong, Qugnaming Zhou, Huakun Yeomans, Jane Li, Yv Li, Shuai Gao, Xiaoxia TI Effect of grassland degradation on aggregate-associated soil organic carbon of alpine grassland ecosystems in the Qinghai-Tibetan Plateau SO EUROPEAN JOURNAL OF SOIL SCIENCE DT Article AB One of the important mechanisms for the stabilization of soil organic carbon (SOC) is its spatial inaccessibility for microbial biodegradation within soil aggregates. However, little has been documented regarding soil aggregate stability with grassland degradation in the alpine region of the Qinghai-Tibetan Plateau (QTP). In this study, we used physical and density fractions to elucidate the mechanisms of differences in SOC in non-degraded and degraded grasslands of two grassland biomes, alpine meadow and alpine steppe in the QTP. There were considerable differences between non-degraded and degraded grasslands for the soil physical and chemical properties, aggregate distribution and aggregate-SOC content. The non-degraded alpine meadow (AMND) had the largest value among all the alpine grasslands for the SOC content of the microaggregate fraction, with values of 31.83 g kg(-1). The degraded grasslands showed significantly larger SOC content of macroaggregates than non-degraded grasslands. The degraded alpine steppe (ASD) had the largest SOC content, with the value of 25.51 g kg(-1). The aggregate distribution of the macroaggregate, microaggregate and free silt+clay fractions was consistent with the variation in SOC content of these three aggregate fractions. The fine intra-aggregate particulate organic matter (fiPOM) content was significantly less in degraded grasslands, indicating that grassland degradation might have disrupted the fiPOM-C. The increase in CO2 emissions was related to the destruction of soil aggregates in the alpine grasslands of the QTP. Highlights Effects of alpine grassland degradation on aggregate-associated SOC were investigated. Used soil aggregate fractions to evaluate the variation of aggregate-associated SOC. Grassland degradation promoted the destruction of soil aggregates in the alpine grasslands of the QTP. Destruction of soil aggregates promoted CO2 emissions in the degraded alpine grasslands of the QTP. C1 [Dong, Shikui; Zhang, Jing; Li, Yuanyuan; Liu, Shiliang; Li, Yv; Li, Shuai; Gao, Xiaoxia] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Dong, Qugnaming] Qinghai Univ, Qinghai Acad Anim Husb & Vet Sci, Xining, Qinghai, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining, Qinghai, Peoples R China. [Yeomans, Jane] EARTH Univ, Res Dept, San Jose, Costa Rica. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 16 Z9 20 PD JAN PY 2020 VL 71 IS 1 BP 69 EP 79 DI 10.1111/ejss.12835 UT WOS:000506301800007 DA 2023-03-23 ER PT J AU Du, CJ Jing, J Shen, Y Liu, HX Gao, YH AF Du, Chenjun Jing, Jie Shen, Yuan Liu, Haixiu Gao, Yongheng TI Short-term grazing exclusion improved topsoil conditions and plant characteristics in degraded alpine grasslands SO ECOLOGICAL INDICATORS DT Article AB Grazing exclusion by fencing is one of the most effective practices to recover the degraded alpine grasslands in Tibetan Plateau. In the present study, the effects of 8-year (GE8) and 4-year (GE4) grazing exclusion were studied in comparison with free grazing (FG) in the plant-soil ecosystems of alpine grasslands. Within fencing, improved plant characteristics such as aboveground biomass (AGB), belowground biomass (BGB) and plant total cover developed without grazing and trampling were observed. Also, there were significant improvements of soil organic carbon (SOC), ammonia nitrogen (NH 4(+)-N) and dissolved organic carbon (DOC) concentrations usually in the topsoil (0-30 cm) but a stable C:N ratio with the number of years of grazing exclusion. Fencing enhanced soil main enzyme (invertase, phosphatase, urease and beta-glucosidase) activities by providing sufficient substrates for microbial activities. Unexpectedly, GE4 had higher soil invertase, phosphatase, urease and beta-glucosidase activities than GE8, which had less plant diversity, richness and higher total cover causing a lowering of soil temperature. Additionally, the results supported the allometric allocation hypothesis for the ABG versus BGB in the grasslands of Tibetan Plateau. Our results indicated that SOC and BGB can be used as indicators of the restoration process of degraded alpine grassland. Cautions should be taken for a long-term fencing in degraded alpine grasslands because of the loss of plant richness, diversity and soil enzyme activities. The present results also suggested that a suitable grazing regime combined with fencing should be focused in the future study of the alpine grasslands. Research results obtained in the present study should, therefore, be helpful to offer a better guidance towards the management practices of the degraded alpine grasslands. C1 [Du, Chenjun; Gao, Yongheng] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Sichuan, Peoples R China. [Du, Chenjun; Jing, Jie; Gao, Yongheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Sichuan, Peoples R China. [Du, Chenjun; Jing, Jie] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Shen, Yuan] Mianyang Teachers Coll, Coll Life Sci & Biotechnol, Mianyang 621000, Sichuan, Peoples R China. [Liu, Haixiu] Ledu Forestry Bur, Haidong 810699, Peoples R China. RP Gao, YH (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Sichuan, Peoples R China. EM yhgao@imde.ac.cn TC 22 Z9 27 PD JAN PY 2020 VL 108 AR 105680 DI 10.1016/j.ecolind.2019.105680 UT WOS:000493902400011 DA 2023-03-23 ER PT J AU Feng, X Qu, JJ Tan, LH Fan, QB Niu, QH AF Feng, Xiao Qu, Jianjun Tan, Lihai Fan, Qingbin Niu, Qinghe TI Fractal features of sandy soil particle-size distributions during the rangeland desertification process on the eastern Qinghai-Tibet Plateau SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Purpose Fractal theory has been frequently applied to quantify soil particle-size distributions (PSDs) and evaluate soil degradation. Eolian desertification occurring on the eastern Qinghai-Tibet Plateau is threatening the ecological environment. It is essential to investigate the desertification process by adopting the concept of space as a substitute for time. Here, the fractal features of soil PSDs and their relationships with selected soil properties and wind erosion and deposition were studied. Materials and methods The tested soil samples were collected from rangelands with four different degrees of desertification (light, medium, severe, and extremely severe). Soil particle sizes were measured by a laser diffraction particle-size analyzer. Soil moisture and soil bulk density were determined by the soil weight difference before and after oven-drying for 8 h. Soil organic carbon was determined by the K2Cr2O7-H2SO4 oxidation method and soil total nitrogen was analyzed using the Kjeldahl digestion procedure. Wind tunnel experiments were conducted to simulate wind erosion and deposition during the desertification process. Values of the fractal dimension of soil PSDs were calculated using the volume-based fractal model. ANOVA with an LSD test and Pearson correlation analysis were used to analyze whether different parameters used in the fractal model influenced the results of the fractal dimensions and were reasonable to be applied. Results and discussion Different parameters, including the arithmetic mean size and the upper sieve size of two successive sieve sizes, values of R-min, and the number of data points used in the fractal model, rarely influenced the results of the fractal dimensions (p > 0.05). The D values showed a significantly positive correlation with the clay and silt contents and a strong negative correlation with the sand contents. Along the degrees of desertification from light to extremely severe, the contents of clay, silt, and very fine sand decreased while the fine sand contents increased, and the D values decreased accordingly. Rangelands with heavier desertification and lower D values were more easily exposed to wind erosion, relating to the further loss of soil organic carbon, soil total nitrogen, and soil moisture and increased soil bulk density. The soil depth could affect soil PSDs and the selected soil properties of rangelands under light and medium degrees of desertification but rarely influenced those of severely and extremely severely desertified lands. Conclusions Different parameters, including the arithmetic mean size, the upper sieve size, values of Rmin, and the number of data points used in the fractal model, had no impacts on the results of the fractal dimensions, and were reasonable to be applied. We suggest the fractal dimension as an effective indicator to evaluate soil environment changes induced by desertification. C1 [Feng, Xiao; Qu, Jianjun; Tan, Lihai; Fan, Qingbin; Niu, Qinghe] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Dunhuang Gobi Desert Res Stn, Lanzhou 730000, Peoples R China. [Feng, Xiao; Fan, Qingbin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Qu, JJ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Dunhuang Gobi Desert Res Stn, Lanzhou 730000, Peoples R China. EM qujianj@lzb.ac.cn TC 17 Z9 19 PD JAN PY 2020 VL 20 IS 1 BP 472 EP 485 DI 10.1007/s11368-019-02392-6 UT WOS:000515824400041 DA 2023-03-23 ER PT J AU Ni, Y Zhou, YK Fan, JF AF Ni, Yong Zhou, Yuke Fan, Junfu TI Characterizing Spatiotemporal Pattern of Vegetation Greenness Breakpoints on Tibetan Plateau Using GIMMS NDVI3g Dataset SO IEEE ACCESS DT Article AB Due to the harsh natural environment on the Tibetan Plateau (TP), its vegetation is sensitive to climate change. Therefore, it is essential to characterize long-term vegetation shifts for understanding of land surface processes across the TP. Gradual greening or browning growth in vegetation greenness is detectable while the alternating process between greening and browning, its timing, and type remain unclear. In this paper, breakpoint in time series of a satellite-derived vegetation index was detected at pixel-level during 1982-2012. The long-term growth procedure of vegetation was then characterized by combining the greening/browning trend for the two sub-periods, on each side of the breakpoint. The combinations of greening/browning status were classified into three categories (monotonic, interrupted and growth reversal). Possible causes for abrupt vegetation changes are discussed in the content of climate change and grassland management. Results show that breakpoints are temporally widely distributed and have significant spatial heterogeneity. About 21 & x0025; (11 & x0025;) of the vegetated area showed significant greening (browning) trends. Vegetation in central and eastern TP has tended to be greening. Browning trends were particularly evident in the southern and northeastern TP and were scarce in the west. About 32 & x0025; of the vegetation was found to change significantly in this analysis. Greening trends occurred more often than browning trends and exhibited both a monotonic and an interrupted growing process. Trend reversal in vegetation was dominated by declining trends. Breakpoints in monotonic and interrupted trends were concentrated in some time points, but those with reversal trends were discretely distributed over time span. Among different ecosystem types, desert ecosystems presented the most significant greening trends, accounting for 53 & x0025; of plant-covered desert. Conspicuous degraded trends were identified on alpine sparse vegetated area. Statistically, breakpoints in precipitation and air temperature are not consistent with those in vegetation greenness index. And grazing projects have not posed a significant effect on abrupt shifts in vegetation greenness. C1 [Ni, Yong] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China. [Ni, Yong] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Ni, Yong] China Natl Environm Monitoring Ctr, Beijing 100012, Peoples R China. [Zhou, Yuke] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Fan, Junfu] Shandong Univ Technol, Sch Civil & Architectural Engn, Zibo 255049, Peoples R China. RP Zhou, YK (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China.; Fan, JF (通讯作者)，Shandong Univ Technol, Sch Civil & Architectural Engn, Zibo 255049, Peoples R China. EM zhouyk@igsnrr.ac.cn; fanjf@sdut.edu.cn TC 6 Z9 6 PY 2020 VL 8 BP 56518 EP 56527 DI 10.1109/ACCESS.2020.2982661 UT WOS:000527411700059 DA 2023-03-23 ER PT J AU Wu, SY Zhou, W Yan, K Zhang, XX AF Wu, Shuying Zhou, Wei Yan, Kai Zhang, Xunxun TI Response of the Water Conservation Function to Vegetation Dynamics in the Qinghai & x2013;Tibetan Plateau Based on MODIS Products SO IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING DT Article AB With the increasing demand for global water resources and general deterioration of the ecological environment of the Qinghai-Tibetan Plateau, changes to the water conservation functions of ecosystems and the impact mechanisms have attracted great attention. Currently, the research on water conservation has mainly focused on a single biome type, in particular, forests. Few studies explore the differences in water conservation functions of different biome types. Research on this topic mostly utilizes field investigations and sample plot settings to explore the differences in water conservation capacity of a small number of tree species, but these methods are limited in time and space. Therefore, this study uses MODIS products to evaluate the water conservation function of different biome types in the Qinghai-Tibetan Plateau. Dynamic monitoring of the vegetation and water conservation capacity in the study area and research on the responses of the water conservation functions of different biome types were conducted. The results indicate that the vegetation of the Qinghai-Tibetan Plateau increased slightly from 2000 to 2015; however, due to the dual influence of climate and topographic factors, the water conservation capacity showed a slight decline. The water conservation service function mainly comes from grassland ecosystems, which are closely related to vegetation density and biome types. Therefore, to greatly improve the water conservation service function of the Qinghai-Tibetan Plateau, the management and planting of vegetation should be conducted according to the optimal vegetation coverage area, vegetation quantities and biome types. C1 [Wu, Shuying; Zhou, Wei; Yan, Kai] China Univ Geosci, Sch Land Sci & Technol, Beijing 100083, Peoples R China. [Zhou, Wei] Minist Nat Resources, Key Lab Land Remediat, Beijing 100083, Peoples R China. [Zhou, Wei] Min Area Ecol Restorat Engn Technol Innovat Ctr, Nat Resources Dept, Beijing 100083, Peoples R China. [Zhang, Xunxun] China Geol Survey Bur, Geol Survey Ctr Civil Mil Integrat, Chengdu 610036, Peoples R China. RP Zhou, W (通讯作者)，China Univ Geosci, Sch Land Sci & Technol, Beijing 100083, Peoples R China.; Zhou, W (通讯作者)，Minist Nat Resources, Key Lab Land Remediat, Beijing 100083, Peoples R China. EM wusy@cugb.edu.cn; zhouw@cugb.edu.cn; kaiyan@cugb.edu.cn; zhangxunxun9511@163.com TC 7 Z9 8 PY 2020 VL 13 BP 1675 EP 1686 DI 10.1109/JSTARS.2020.2984830 UT WOS:000534047900001 DA 2023-03-23 ER PT J AU Zhang, XF Zhang, H Wang, C Tang, YX Zhang, B Wu, F Wang, J Zhang, ZJ AF Zhang, Xuefei Zhang, Hong Wang, Chao Tang, Yixian Zhang, Bo Wu, Fan Wang, Jing Zhang, Zhengjia TI Active Layer Thickness Retrieval Over the Qinghai-Tibet Plateau Using Sentinel-1 Multitemporal InSAR Monitored Permafrost Subsidence and Temporal-Spatial Multilayer Soil Moisture Data SO IEEE ACCESS DT Article AB Increasing near-surface temperature over the Qinghai-Tibet Plateau (QTP) has led to permafrost degradation and increasing active layer thickness (ALT). In this study, the ALT was estimated based on ground subsidence monitored by multitemporal interferometric synthetic aperture radar (MT-InSAR) and temporal-spatial multilayer soil moisture data. For the ground subsidence monitoring, a modified Stefan piecewise elevation change model based on air temperature data was integrated into a new small baseline subset (NSBAS) chain. A total of 33 scenes of Sentinel-1 data (S-1) were collected over one year to build the MT-InSAR analysis network. Moreover, both soil moisture active/passive (SMAP) L4 surface and root zone soil moisture data and ERA-Interim reanalysis data were used to build an ALT retrieval model. In particular, the global-scaled soil moisture data (SMAP and ERA-Interim) fraction was separated based on the Sentinel-1 amplitude-based land cover classification results and in situ soil moisture data. A typical ALT estimation method based on the point scale groundwater information was also performed to evaluate the performance of the proposed method. Based on the validation of the ground-based ALT observations, the proposed method outperformed the traditional point scale groundwater information-based method, with a correlation coefficient of 0.67, RMSE of 0.70 and ubRMSE of 0.51, respectively. The ERA-Interim-based estimation results were underestimated due to the overestimation of the ERA-Interim soil moisture data. Obvious differences were observed between the ALT of the alpine meadow areas and alpine desert areas. Our results demonstrate that the combination of temporal-spatial multilayer soil moisture data and the MT-InSAR method with S-1 images is a promising approach for the large-scale characterization of ALT. C1 [Zhang, Xuefei; Zhang, Hong; Wang, Chao; Tang, Yixian; Zhang, Bo; Wu, Fan; Wang, Jing] Chinese Acad Sci, Aerosp Informat Res Inst, Beijing 100094, Peoples R China. [Zhang, Xuefei; Wang, Chao; Wang, Jing] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Zhang, Zhengjia] China Univ Geosci, Fac Informat Engn, Wuhan 430074, Peoples R China. RP Zhang, XF; Tang, YX (通讯作者)，Chinese Acad Sci, Aerosp Informat Res Inst, Beijing 100094, Peoples R China.; Zhang, XF (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM zhanghong@radi.ac.cn; yxtang@ceode.ac.cn TC 13 Z9 13 PY 2020 VL 8 BP 84336 EP 84351 DI 10.1109/ACCESS.2020.2988482 UT WOS:000549526700009 DA 2023-03-23 ER PT J AU Dong, JF Che, RX Jia, SG Wang, F Zhang, B Cui, XY Wang, SP Wang, SP AF Dong, Junfu Che, Rongxiao Jia, Shugang Wang, Fang Zhang, Biao Cui, Xiaoyong Wang, Shiping Wang, Shuping TI Responses of ammonia-oxidizing archaea and bacteria to nitrogen and phosphorus amendments in an alpine steppe SO EUROPEAN JOURNAL OF SOIL SCIENCE DT Article AB With the increasing demands of livestock production, grasslands are under pressure from over-intensified grazing. Phosphorus (P) and nitrogen (N) fertilization is widely employed to meet the nutrient demands of heavy grazing. Although soil ammonia-oxidizers play a critical role in determining N dynamics after fertilizer application, their responses to fertilization are still not well understood in steppe grassland systems. Here, the individual and combined effects of N (0, 7.5 and 15 g N m(-2) year(-1)) and P (0, 3.27, 6.55 and 13.09 g P m(-2) year(-1)) applications on soil ammonia-oxidizers were explored in the Tibetan alpine steppe. Ammonia-oxidizing archaea (AOA) and bacteria (AOB) abundance and community composition were examined using qPCR, terminal restriction fragment length polymorphism and clone libraries. Results showed that AOB diversity was significantly increased by N fertilization and decreased by P fertilization. The abundance of AOB was significantly increased by N fertilization and its interactive effects with P application. In contrast, AOA community diversity and abundance remained unaffected by either N or P application. The AOB abundance and diversity were affected by the direct effects of N fertilization, as well as its indirect effects of N application through available N and ammonium (NH4+), and further analysis showed that NH4+ and pH were the main factors. The changes to the ammonia-oxidizing community altered the total N content of plants and the N:P ratio of Gramineae. Plant P properties were influenced by P addition, which also interacted with soil pH and available N to indirectly affect AOB. Overall, AOB exhibited stronger responses to N and P fertilization of alpine steppe grassland than AOA, and appear to play a critical role in plant nutrient absorption under fertilization management. Highlights Effects of N and P application on AOA and AOB communities were evaluated. AOB, not AOA, responded to N or P, and their interaction, and NH4+ and pH were regulators of AOB. N application affected AOB community, resulting in changes to plant nutrient absorption. P addition affected plant tissue stoichiometry, and thus affected AOB community. C1 [Dong, Junfu; Zhang, Biao; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing, Peoples R China. [Che, Rongxiao] Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming, Yunnan, Peoples R China. [Jia, Shugang] Guangxi Teachers Educ Univ, Minist Educ, Key Lab Environm Change & Resources Use Beibu Gul, Nanning, Peoples R China. [Wang, Fang; Wang, Shuping] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 101408, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. RP Wang, SP (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 101408, Peoples R China. EM wshuping@ucas.ac.cn TC 8 Z9 8 PD SEP PY 2020 VL 71 IS 5 BP 940 EP 954 DI 10.1111/ejss.12911 EA DEC 2019 UT WOS:000504378100001 DA 2023-03-23 ER PT J AU Wang, HJ Peng, PH Kong, XD Zhang, TB Yi, GH AF Wang, Haijun Peng, Peihao Kong, Xiangdong Zhang, Tingbin Yi, Guihua TI Vegetation dynamic analysis based on multisource remote sensing data in the east margin of the Qinghai-Tibet Plateau, China SO PEERJ DT Article AB This study focuses on the vegetation dynamic caused by global environmental change in the eastern margin of the Qinghai-Tibet Plateau (EMQTP). The Qinghai-Tibet Plateau (QTP) is one of the most sensitive areas responding to global environmental change, particularly global climate change, and has been recognized as a hotspot for coupled studies on changes in global terrestrial ecosystems and global climates. An important component of terrestrial ecosystems, vegetation dynamic has become a key issue in global environmental change, and numerous case studies have been conducted on vegetation dynamic trends using multi-source data and multi-scale methods across different study periods. The EMQTP is regarded as a transitional area located between the QTP and the Sichuan basin, and has special geographical and climatic conditions. Although this area is ecologically fragile and sensitive to climate change, few studies about vegetation dynamics have been carried out in this area. Thus, in this study, we used long-term series datasets of GIMMS 3g NDVI and VGT/PROBA-V NDVI to analyze the vegetation dynamics and phenological changes from 1982 to 2018. Validation was performed based on Landsat NDVI and Vegetation Index & Phenology (VIP) data. The results reveal that the year 1998 was a vital turning point in the start of growing season (SGS) in vegetation ecosystems. Before this turning point, the SGS had an average slope of 9.2 days/decade, and after, the average slope was 3.9 days/decade. The length of growing season (LGS) was slightly prolonged between 1982 to 2015. Additionally, the largest national alpine wetland grassland experienced significant vegetation degradation; in autumn, the degraded area accounted for 63.4%. Vegetation degradation had also appeared in the arid valleys of the Yalong River and the Jinsha River. Through validation analysis, we found that the main causes of vegetation degradation are the natural degradation of wetland grassland and human activities, specifically agricultural development and residential area expansion. C1 [Wang, Haijun; Peng, Peihao; Zhang, Tingbin; Yi, Guihua] Chengdu Univ Technol, Coll Earth Sci, Chengdu, Sichuan, Peoples R China. [Wang, Haijun; Kong, Xiangdong] Chengdu Univ Technol, Engn & Tech Coll, Leshan, Sichuan, Peoples R China. [Kong, Xiangdong] Southwest Petr Univ, Sch Civil Engn & Architecture, Chengdu, Sichuan, Peoples R China. RP Wang, HJ; Peng, PH (通讯作者)，Chengdu Univ Technol, Coll Earth Sci, Chengdu, Sichuan, Peoples R China.; Wang, HJ (通讯作者)，Chengdu Univ Technol, Engn & Tech Coll, Leshan, Sichuan, Peoples R China. EM wanghaibo.2006@163.com; peihaop@163.com TC 7 Z9 7 PD DEC 13 PY 2019 VL 7 AR e8223 DI 10.7717/peerj.8223 UT WOS:000502757100006 DA 2023-03-23 ER PT J AU Pan, T Hou, S Liu, YJ Tan, QH AF Pan, Tao Hou, Shuai Liu, Yujie Tan, Qinghua TI Comparison of three models fitting the soil water retention curves in a degraded alpine meadow region SO SCIENTIFIC REPORTS DT Article AB Soil water retention curve (SWRC) plays an important role in simulating soil water movement and assessing soil water holding capacity and availability. Comparison of fitness between different models to determine the best SWRC model of specific regions is required. In this study, three popular models, van Genuchten, Brooks Corey and Gardner model, were selected for comparing in a degraded alpine meadow region on the eastern Tibetan Plateau. Fitness, error distribution along with key parameters were compared. For each soil horizon, the soil moisture content at all soil water potentials decreased consistently with degradation, thereby integrally moving the SWRCs of all soil depths downward with degradation. The differences in SWRCs across various degradation degrees diminished along with soil depth and soil water potential. The Adj.r(2) values of van Genuchten, Brooks Corey and Gardner models ranged in 0.971-0.995, 0.958-0.997, and 0.688-0.909, respectively. The van Genuchten and Brooks Corey models significantly (p < 0.05) outperformed the Gardner model, and have no significant differences in fitness. The fitness of all three models showed no significant changes with degradation. Regardless of degradation degree and soil depth, the fitting error of van Genuchten and Brooks Corey models was mainly distributed in the higher (from -100 hPa to -500 hPa) and lower (below -10000 hPa) potential sections. With regard to the parameters of van Genuchten and Brooks Corey models, the field capacity (theta s), and permanent wilting moisture were highly coherent with Adj.r(2) values of higher than 0.98, while the curve shape parameter (theta r), and air entry pressure of the Brooks Corey model were much lower than those of the van Genuchten model with Adj.r(2) values of lower than 0.91. The SWRCs with varying degrees of degradation are best fitted by both van Genuchten and Brooks Corey models but cannot be fitted by Gardner model. Soil water holding capacity decreased with degradation especially in the top soil (0 cm to 30 cm), but the curve shape of all SWRCs did not change significantly with degradation. C1 [Pan, Tao; Hou, Shuai; Liu, Yujie; Tan, Qinghua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Hou, Shuai] Chinese Acad Agr Sci, Key Lab Crop Physiol & Ecol, Inst Crop Sci, Minist Agr & Rural Affairs, Beijing 100081, Peoples R China. RP Liu, YJ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM liuyujie@igsnrr.ac.cn TC 12 Z9 12 PD DEC 5 PY 2019 VL 9 AR 18407 DI 10.1038/s41598-019-54449-8 UT WOS:000501552400001 DA 2023-03-23 ER PT J AU Han, WY Lu, HT Liu, GH Wang, JS Su, XK AF Han, Wangya Lu, Huiting Liu, Guohua Wang, Jingsheng Su, Xukun TI Quantifying Degradation Classifications on Alpine Grassland in the Lhasa River Basin, Qinghai-Tibetan Plateau SO SUSTAINABILITY DT Article AB The Qinghai-Tibetan Plateau (QTP) has the world's largest alpine grassland ecosystem. The QTP ecosystem is extremely fragile and suffers continuous degradation. An accurate determination of the status of alpine grassland is the first crucial step in monitoring its degradation. A novel method combining field survey with remote sensing information based on ecological indicators is proposed. The degradation classification of alpine grassland was identified by multivariate hierarchical analysis based on 270 field plots. The spatial pattern of alpine grassland degradation was mapped by determining remote sensing variables that corresponded to field indicators of the degradation classification system. The results showed that clustering analysis divided the degradation classification of alpine grassland into five classes: Non-Degraded (ND), Slightly Degraded (SLD), Moderately Degraded (MD), Severely Degraded (SD), and Extremely Degraded (ED). The most significant factors for alpine grassland degradation included the dominance of Cyperaceae plants, soil total nitrogen content, soil organic carbon content, soil total carbon content, soil bulk density, soil pH, dominance of miscellaneous plants, and elevation among all 17 variables. The assessment and mapping of alpine grassland degradation provide an important basis for alpine grassland protection and management, particularly at a large scale. C1 [Han, Wangya; Lu, Huiting; Liu, Guohua; Su, Xukun] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China. [Han, Wangya; Lu, Huiting; Liu, Guohua; Su, Xukun] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Wang, Jingsheng] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. RP Liu, GH; Su, XK (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China.; Liu, GH; Su, XK (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM wyhan_st@rcees.ac.cn; htlu_st@rcees.ac.cn; ghliu@rcees.ac.cn; wangjsh@igsnrr.ac.cn; xksu@rcees.ac.cn TC 4 Z9 4 PD DEC 2 PY 2019 VL 11 IS 24 AR 7067 DI 10.3390/su11247067 UT WOS:000506899000170 DA 2023-03-23 ER PT J AU Che, RX Wang, YF Li, KX Xu, ZH Hu, JM Wang, F Rui, YC Li, LF Pang, Z Cui, XY AF Che, Rongxiao Wang, Yanfen Li, Kexin Xu, Zhihong Hu, Jinming Wang, Fang Rui, Yichao Li, Linfeng Pang, Zhe Cui, Xiaoyong TI Degraded patch formation significantly changed microbial community composition in alpine meadow soils SO SOIL & TILLAGE RESEARCH DT Article AB Approximately half of global grasslands are degraded. Although soil microbes play a key role in ecosystem functioning, their response to grassland degradation has not been fully investigated. In particular, degraded patch formation is the main feature of alpine meadow degradation, but little is known about its effect on soil microbes. In this study, soils were collected from three patch-degraded Tibetan alpine meadows to examine the effects of degraded patch formation on soil microbial communities. The alpine meadows at the three sites were in the third to fifth stages of degradation, respectively. Soil microbial abundance and community structure were determined through real-time PCR and MiSeq sequencing, respectively. The results showed that the degraded patch formation significantly decreased microbial respiration rates, changed the interaction patterns among microbial taxa, and increased fungal diversity, but did not significantly affect microbial abundance. Additionally, both prokaryotic and fungal community composition was significantly altered by the degraded patch formation. The functional predictions based on FAPROTAX and FUNGuild suggested that degraded patch formation significantly increased the proportion of nitrifiers, plant pathogenic fungi, and saprotrophic fungi, especially when mattic epipedons were eroded. The increased relative abundance of nitrifiers and pathogenic fungi can aggravate the risk of nitrogen leaching and plant diseases, respectively. Therefore, degraded patch formation can impede the recovery of degraded alpine meadows by changing soil microbial community composition. C1 [Che, Rongxiao; Li, Kexin; Hu, Jinming] Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming 650091, Yunnan, Peoples R China. [Che, Rongxiao; Wang, Yanfen; Wang, Fang; Li, Linfeng; Pang, Zhe; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Che, Rongxiao; Xu, Zhihong; Wang, Fang; Li, Linfeng] Griffith Univ, Sch Environm & Sci, Environm Futures Res Inst, Brisbane, Qld 4111, Australia. [Che, Rongxiao] Yunnan Univ, Yunnan Key Lab Int Rivers & Transboundary Ecosecu, Kunming 650091, Yunnan, Peoples R China. [Rui, Yichao] Univ Wisconsin, Dept Soil Sci, Madison, WI 53706 USA. [Cui, Xiaoyong] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Cui, Xiaoyong] Chinese Acad Sci, Huairou Ecoenvironm Observ, Beijing 101408, Peoples R China. RP Wang, YF; Cui, XY (通讯作者)，19A Yuquan Rd, Beijing 100049, Peoples R China. EM yfwang@ucas.ac.cn; cuixy@ucas.ac.cn TC 56 Z9 61 PD DEC PY 2019 VL 195 AR 104426 DI 10.1016/j.still.2019.104426 UT WOS:000494053700060 DA 2023-03-23 ER PT J AU Ganjurjav, H Zhang, Y Gornish, ES Hu, GZ Li, Y Wan, YF Gao, QZ AF Ganjurjav, Hasbagan Zhang, Yong Gornish, Elise S. Hu, Guozheng Li, Yue Wan, Yunfan Gao, Qingzhu TI Differential resistance and resilience of functional groups to livestock grazing maintain ecosystem stability in an alpine steppe on the Qinghai-Tibetan Plateau SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Ecosystem stability is one of the main factors maintaining ecosystem functioning and is closely related to temporal variability in productivity. Resistance and resilience reflect tolerance and recovering ability, respectively, of a plant community under perturbation, which are important for maintaining the stability of ecosystems. Generally, heavy grazing reduces the stability of grassland ecosystems, causing grassland degradation. However, how livestock grazing affects ecosystem stability is unclear in alpine steppe ecosystems. We conducted a five-year grazing experiment with Tibetan sheep in a semi-arid alpine steppe on the Qinghai-Tibetan Plateau, China. The experimental treatments included no grazing (NG), light grazing (LG, 2.4 sheep per ha), moderate grazing (MG, 3.6 sheep per ha) and heavy grazing (HG, 6.0 sheep ha). We calculated resistance and resilience of three plant functional groups and ecosystem stability under the three grazing intensities using aboveground primary productivity. The results showed that with increasing grazing intensity, aboveground biomass of each functional group significantly decreased. As grazing intensity increased, the resistance of forbs first increased then decreased. The resilience of graminoids in HG was significantly lower than in LG plots, but the resilience of legumes in HG was higher than in LG and MG plots. The resilience of graminoids was significantly higher than legume and forbs under LG and MG treatments. In HG treatments, resilience of legumes was higher than graminoids and forbs. Ecosystem stability did not change under different grazing intensities, because of dissimilar performance of the resilience and resistance of functional groups. Our results highlight how the differential resistance and resilience of different function groups facilitate the tolerance of alpine steppe to grazing under even a heavy intensity. However, the degradation risk of alpine steppe under heavy grazing still needs to be considered in grassland management due to sharp decreases of productivity. C1 [Ganjurjav, Hasbagan; Hu, Guozheng; Li, Yue; Wan, Yunfan; Gao, Qingzhu] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, 12 South St Zhongguancun, Beijing 100081, Peoples R China. [Zhang, Yong] Southwest Forestry Univ, Coll Wetlands, Natl Plateau Wetlands Res Ctr, Kunming 650224, Yunnan, Peoples R China. [Gornish, Elise S.] Univ Arizona, Sch Nat Resources & Environm, Tucson, AZ 85821 USA. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, 12 South St Zhongguancun, Beijing 100081, Peoples R China. EM gaoqingzhu@caas.cn TC 21 Z9 22 PD DEC 1 PY 2019 VL 251 AR 109579 DI 10.1016/j.jenvman.2019.109579 UT WOS:000494052300051 DA 2023-03-23 ER PT J AU Huang, Z Sun, L Liu, Y Liu, YF Lopez-Vicente, M Wei, XH Wu, GL AF Huang, Ze Sun, Lei Liu, Yu Liu, Yi-Fan Lopez-Vicente, Manuel Wei, Xue-Hong Wu, Gao-Lin TI Alfalfa planting significantly improved alpine soil water infiltrability in the Qinghai-Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB The Qinghai-Tibetan Plateau is undergoing serious water and soil conservation problem resulted from grassland degradation, that is not conductive to the sustainability of grassland ecologicla function and agriculture productivity. The soil infiltrability has significance in reducing runoff yield and soil loss. However, characterization of the soil infiltration capacity of planted grasslands, such as alfalfa (Medicago Sativa), with different growing years in this high-altitude alpine region is still lacking. In this study, the variation of soil infiltration rate and characteristics were analyzed in alfalfa grasslands with three growth years (two-, four- and seven-year-old). A corn cropland was used as the control field, and the infiltration was monitored using the automatic soil infiltrability measurement system. To determine the influence factors on infiltration rate (IR), soil characteristics and root dry weight density (RDWD) at 0-30 cm soil depth were measured. The results indicated that the comprehensive index of soil water infiltration capacity (FIR) of the seven-year-old alfalfa grassland (0.69) was the highest, followed by the two- (0.05) and four-year-old (0.11) grasslands, being these values significantly higher than that of the corn field (-0.85, P < 0.05). SWC was positively correlated with IR during the fast infiltration stage (IR-I). The soil bulk density and organic matter were negatively correlated with IR, while RDWD was positively related to IR. Our results showed that alfalfa planting improved soil infiltrability, and this upgrade increased with the age growth. This study provided significant information to introduce soil-erosion-control practices for alpine soil and highlights the importance of ecological function of planted grasslands in alpine area of the Qinghai-Tibetan Plateau. C1 [Huang, Ze; Sun, Lei; Wei, Xue-Hong; Wu, Gao-Lin] Tibet Agr & Anim Husb Univ, Anim Sci Coll, Nyingchi 860000, Peoples R China. [Huang, Ze; Liu, Yu; Liu, Yi-Fan; Wu, Gao-Lin] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Lopez-Vicente, Manuel] CSIC, EEAD, Expt Stn Aula Dei, Dept Soil & Water, Zaragoza 50059, Spain. RP Wu, GL (通讯作者)，Tibet Agr & Anim Husb Univ, Anim Sci Coll, Nyingchi 860000, Peoples R China. EM wugaolin@nwsuaf.edu.cn TC 21 Z9 22 PD DEC 1 PY 2019 VL 285 AR 106606 DI 10.1016/j.agee.2019.106606 UT WOS:000500213400003 DA 2023-03-23 ER PT J AU Latif, A Ilyas, S Zhang, YJ Xin, YQ Zhou, L Zhou, Q AF Latif, Aamir Ilyas, Sana Zhang, Yangjian Xin, Yuqin Zhou, Lin Zhou, Quan TI Review on global change status and its impacts on the Tibetan Plateau environment SO JOURNAL OF PLANT ECOLOGY DT Review AB The Tibetan Plateau (TP) holds fundamental ecological and environmental significances to China and Asia. The TP also lies in the core zone of the belt and road initiative. To protect the TP environment, a comprehensive screening on current ecological research status is entailed. The teased out research gap can also be utilized as guidelines for the recently launched major research programs, i.e. the second TP scientific expedition and silk and belt road research plan. The findings showed that the TP has experienced significant temperature increase at a rate of 0.2 degrees C per decade since 1960s. The most robust warming trend was found in the northern plateau. Precipitation also exhibited an increasing trend but with high spatial heterogeneity. Changing climates have caused a series of environmental consequences, including lake area changes, glacier shrinkage, permafrost degradation and exacerbated desertification. The rising temperature is the main reason behind the glaciers shrinkage, snow melting, permafrost degradation and lake area changes on the TP and neighboring regions. The projected loss of glacial area on the plateau is estimated to be around 43% by 2070 and 75% by the end of the century. Vegetation was responsive to the changed environments, varied climates and intensified human activities by changing phenology and productivity. Future global change study should be more oriented toward integrating various research methods and tools, and synthesizing diverse subjects of water, vegetation, atmosphere and soil. [GRAPHICS] C1 [Latif, Aamir; Zhang, Yangjian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Latif, Aamir; Ilyas, Sana] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Ilyas, Sana] Inst Atmospher Phys, Key Lab Reg Climate Environm Temperate East Asia, Beijing 100029, Peoples R China. [Zhang, Yangjian] Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Xin, Yuqin] Sanmenxia Acad Environm Sci, Sanmenxia 472000, Peoples R China. [Zhou, Lin; Zhou, Quan] State Grid Corp China, Southwest Branch, Chengdu 610094, Sichuan, Peoples R China. RP Zhang, YJ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. EM zhangyj@igsnrr.ac.cn TC 14 Z9 15 PD DEC PY 2019 VL 12 IS 6 BP 917 EP 930 DI 10.1093/jpe/rtz038 UT WOS:000503278500001 DA 2023-03-23 ER PT J AU Niu, KC Feng, F Xu, Q Badingqiuying Zhang, ST AF Niu, Kechang Feng, Feng Xu, Qian Badingqiuying Zhang, Shiting TI Impoverished soil supports more plateau pika through lowered diversity of plant functional traits in Tibetan alpine meadows SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Frequent outbreaks of plateau pika (Ochotona curzoniae) have become a major challenge for the sustainability of Tibetan rangeland, although top-down control has been widely employed since the 1960s over the plateau. Based on studies on plant trait-mediated soil-plant-herbivore relations, we hypothesized that impoverished soil was a consequence of rangeland degradation as well as a cause of increasing pika numbers through lowered functional trait diversity (FD) of the plant community that provides advantages for pika fitness. At three sites of alpine meadows on the eastern Tibetan Plateau, we counted active burrows of pika in 27 plots (i.e., 9 plots per site) distributed along a gradient of soil fertility. For every plant species within each plot, we measured five functional traits (e.g., mature height, SLA: specific leaf area, LDMC: leaf dry matter content, and leaf N and P: leaf nitrogen and phosphorus concentrations), indicating plant performance in response to changing soil fertility and impacting the fitness of pika. We employed Bayesian regression, structural equation modeling and network analyses to assess causal relations from soil fertility to FD and burrow density. The results show i) there was no significant difference in burrow density between three sites; spatial variation among plots in terms of soil fertility, plant species diversity and FD accounted for 57%-72%, 26%-41% and 59%-73%, respectively, of the variation in burrow density; ii) the burrow density was associated positively with soil moisture and organic matter, plant coverage, forb abundance and FD of leaf P, but negatively with soil nutrients, plant species diversity and FD for SLA, height and leaf N; and iii) deficiency of soil P potentially resulted in an increase in pika density, likely through lowered FD of SLA and height, with other soil factors and FD of leaf nutrients indirectly associated with burrow density. Our study suggested that under the joint effect of intensive grazing by livestock and output of livestock products from region, deficiency of soil P potentially increased pika density, likely by supporting more and diverse food resources while decreasing the risk of being preyed upon. Control of pika outbreak should pay more attention to bottom-up restoration of degraded soil and vegetation via traditional rotational grazing and promotion of recycling and compensation of lost soil P and plant trait diversity. C1 [Niu, Kechang; Feng, Feng; Xu, Qian] Nanjing Univ, Sch Life Sci, Dept Ecol, Nanjing 210023, Jiangsu, Peoples R China. [Badingqiuying] Qinghai Normal Univ, Coll Geog Sci, Xining 810008, Qinghai, Peoples R China. [Zhang, Shiting] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. RP Niu, KC (通讯作者)，Nanjing Univ, Sch Life Sci, Dept Ecol, Nanjing 210023, Jiangsu, Peoples R China. EM kechangniu@nju.edu.cn TC 7 Z9 9 PD DEC 1 PY 2019 VL 285 AR 106621 DI 10.1016/j.agee.2019.106621 UT WOS:000500213400012 DA 2023-03-23 ER PT J AU Tang, Z Zhang, YJ Cong, N Wimberly, M Wang, L Huang, K Li, JX Zu, JX Zhu, YX Chen, N AF Tang, Ze Zhang, Yangjian Cong, Nan Wimberly, Michael Wang, Li Huang, Ke Li, Junxiang Zu, Jiaxing Zhu, Yixuan Chen, Ning TI Spatial pattern of pika holes and their effects on vegetation coverage on the Tibetan Plateau: An analysis using unmanned aerial vehicle imagery SO ECOLOGICAL INDICATORS DT Article AB The pika (Ochotona curzoniae) hole is an important landscape feature in the Tibetan Plateau (TP) grasslands, and it indicates grassland degradation levels due to the destruction caused by pika burrowing activities on grasslands. However, no studies have ever explored landscape patterns of pika holes and their effects on adjacent vegetation coverage. Taking meadow grasslands in Northern Tibet as an example, this study gathered unmanned aerial vehicle (UAV) images and explored landscape patterns of pika holes and their effects on grass coverage in the surroundings. The performances of two classification methods, including the decision tree classification based on Fully Constrained Least Squares (FDC) and the object-oriented classification (OBC) were compared in recognizing sizes and shapes of pika holes. The results showed that: (1) The object-oriented classification exhibits higher classification accuracy in identifying pika holes. (2) The average size of pika holes in the study area is 0.01 m(2) and they exhibit clustered distribution patterns. The average distance between any two nearest pika hole patches is 0.79 m. (3) It presents a significant quadratic relationship between the number of pika holes and grass coverage. (4) The average effective distance of pika holes on the surrounding grass coverage is 20 cm. The findings of this study can provide guidelines for pika control and improve grassland management on the TP. C1 [Tang, Ze; Zhang, Yangjian; Cong, Nan; Huang, Ke; Zu, Jiaxing; Zhu, Yixuan; Chen, Ning] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Zhang, Yangjian] Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Tang, Ze; Zhang, Yangjian; Zu, Jiaxing; Zhu, Yixuan; Chen, Ning] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. [Wimberly, Michael] Univ Oklahoma, Sch Geog & Environm Sustainabil, Oklahoma City, OK 73019 USA. [Wang, Li; Li, Junxiang] Peking Univ, Shenzhen Grad Sch, Shenzhen 518055, Peoples R China. RP Zhang, YJ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. EM tangz.17b@igsnrr.ac.cn; zhangyj@igsnrr.ac.cn; congnan@igsnrr.ac.cn; mcwimberly@ou.edu; wli0034@pku.edu.cn; huangk.13b@igsnrr.ac.cn; junxiang@pku.edu.cn; zujx.15b@igsbrr.ac.cn; zhuyx.16s@igsnrr.ac.cn; chenn.16b@igsnrr.ac.cn TC 12 Z9 14 PD DEC PY 2019 VL 107 AR 105551 DI 10.1016/j.ecolind.2019.105551 UT WOS:000490757500015 DA 2023-03-23 ER PT J AU Wang, R Dong, ZB Zhou, ZC AF Wang Rui Dong Zhi-bao Zhou Zheng-chao TI Changes in the depths of seasonal freezing and thawing and their effects on vegetation in the Three-River Headwater Region of the Tibetan Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Frozen ground degradation plays an important role in vegetation growth and activity in high-altitude cold regions. This study estimated the spatiotemporal variations in the active layer thickness (ALT) of the permafrost region and the soil freeze depth (SFD) in the seasonally frozen ground region across the Three Rivers Source Region (TRSR) from 1980 to 2014 using the Stefan equation, and differentiated the effects of these variations on alpine vegetation in these two regions. The results showed that the average ALT from 1980 to 2014 increased by 23.01 cm/10a, while the average SFD decreased by 3.41 cm/10a, and both changed intensively in the transitional zone between the seasonally frozen ground and permafrost. From 1982-2014, the increase in the normalized difference vegetation index (NDVI) and the advancement of the start of the vegetation growing season (SOS) in the seasonally frozen ground region (0.0078/10a, 1.83d/10a) were greater than those in the permafrost region (0.0057/10a, 0.39d/10a). The results of the correlation analysis indicated that increases in the ALT and decreases in the SFD in the TRSR could lead to increases in the NDVI and advancement of the SOS. Surface soil moisture played a critical role in vegetation growth in association with the increasing ALT and decreasing SFD. The NDVI for all vegetation types in the TRSR except for alpine vegetation showed an increasing trend that was significantly related to the SFD and ALT. During the study period, the general frozen ground conditions were favorable to vegetation growth, while the average contributions of ALT and SFD to the interannual variation in the NDVI were greater than that of precipitation but less than that of temperature. C1 [Wang Rui; Dong Zhi-bao; Zhou Zheng-chao] Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Shaanxi, Peoples R China. RP Wang, R (通讯作者)，Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Shaanxi, Peoples R China. EM wangrui227@126.com; zbdong@snnu.edu.cn; zczhou@snnu.edu.cn TC 6 Z9 8 PD DEC PY 2019 VL 16 IS 12 BP 2810 EP 2827 DI 10.1007/s11629-019-5450-7 UT WOS:000502451800009 DA 2023-03-23 ER PT J AU Song, MH Zong, N Jiang, J Shi, PL Zhang, XZ Gao, JQ Zhou, HK Li, YK Loreau, M AF Song, Ming-Hua Zong, Ning Jiang, Jing Shi, Pei-Li Zhang, Xian-Zhou Gao, Jun-Qin Zhou, Hua-Kun Li, Yi-Kang Loreau, Michel TI Nutrient-induced shifts of dominant species reduce ecosystem stability via increases in species synchrony and population variability SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The mechanisms underlying nutrient-induced diversity-stability relationships have been examined extensively. However, the effects of nutrient-induced shifts of dominant species on ecosystem stability have rarely been evaluated. We compiled a dataset from a long-term nitrogen (N) and phosphorus (P) enrichment experiment conducted in an alpine grassland on the Tibetan Plateau to test the effects of nutrient-induced shifts of dominant species on stability. Our results show that N enrichment increased synchrony among the dominant species, which contributed to a significant increase in synchrony of the whole community. Meanwhile, N-induced shifts in dominant species composition significantly increased population variability. Increases in species synchrony and population variability resulted in a decline in ecosystem stability. Our study has important implications for progress in understanding the role of plant functional compensation in the stability of ecosystem functions, which is critical for better understanding the mechanisms driving both community assembly and ecosystem functions. (C) 2019 Elsevier B.V. All rights reserved. C1 [Song, Ming-Hua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, A11 Datun Rd, Beijing 100101, Peoples R China. [Zong, Ning; Shi, Pei-Li; Zhang, Xian-Zhou] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Natl Ecol Res Stn, A11 Datun Rd, Beijing 100101, Peoples R China. [Jiang, Jing] Nanjing Agr Inst Jiangsu Hilly Reg, Nanjing 210046, Jiangsu, Peoples R China. [Gao, Jun-Qin] Beijing Forestry Univ, Sch Nat Conservat, Qinghua East Rd 35, Beijing 100083, Peoples R China. [Song, Ming-Hua; Zhou, Hua-Kun; Li, Yi-Kang] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, 59 Xiguan Dajie, Xining 810008, Qinghai, Peoples R China. [Loreau, Michel] CNRS, Ctr Biodivers Theory & Modelling, Theoret & Expt Ecol Stn, F-09200 Moulis, France. [Loreau, Michel] Paul Sabatier Univ, F-09200 Moulis, France. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Natl Ecol Res Stn, A11 Datun Rd, Beijing 100101, Peoples R China. EM shipl@igsnrr.ac.cn TC 19 Z9 21 PD NOV 20 PY 2019 VL 692 BP 441 EP 449 DI 10.1016/j.scitotenv.2019.07.266 UT WOS:000484994700044 DA 2023-03-23 ER PT J AU Guo, N Degen, AA Deng, B Shi, FY Bai, YF Zhang, T Long, RJ Shang, ZH AF Guo, Na Degen, A. Allan Deng, Bin Shi, Fuyu Bai, Yanfu Zhang, Tao Long, Ruijun Shang, Zhanhuan TI Changes in vegetation parameters and soil nutrients along degradation and recovery successions on alpine grasslands of the Tibetan plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Understanding the changes in vegetation parameters and soil nutrients in the different stages of grasslands degradation and recovery is crucial for assessing and restoring degraded grasslands. Consequently, we determined above-ground vegetation and soil C, N and P concentrations and their stoichiometry in different degradation and recovery stages on the Tibetan Plateau. Four degradation succession stages, GKC: Grass-Kobresia community, KHC: Kobresia humilis community, KPC: Kobresia pygmaea community, and FBC: forbs - black soil beach community, and three recovery succession stages, FG: freely grazed, RG: restricted grazed, and NG: non-grazed, were identified. Above-ground biomass and vegetation coverage decreased with degradation succession and there was a concomitant shift of plant functional groups to more above-ground biomass of forbs and less biomass of grasses and sedges. The highest species diversity emerged in the K. pygmaea succession stage, mainly due to an influx of Compositae. Significant differences in soil total nitrogen (TN), total phosphorus (TP) and soil organic carbon (SOC) concentrations occurred in the 0-10 and 10-20 cm layers among degradation successions. Vegetation cover, above-ground biomass, soil TN and SOC, as well as C:N and C:P ratios increased in non-grazed grasslands when compared to grazed grasslands. Soil TN, TP and SOC concentrations decreased with increasing soil depths across all degradation and recovery successions. In addition, soil nutrients and their stoichiometry were affected by above-ground biomass. We concluded that grazing exclusion could improve the above-ground vegetation and soil nutrients of degraded alpine grasslands, but that the rate of recovery was related to the degree of degradation. C1 [Guo, Na; Deng, Bin; Shi, Fuyu; Bai, Yanfu; Zhang, Tao; Long, Ruijun; Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Degen, A. Allan] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, IL-8410500 Beer Sheva, Israel. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. EM shangzhh@lzu.edu.cn TC 45 Z9 49 PD NOV 15 PY 2019 VL 284 AR 106593 DI 10.1016/j.agee.2019.106593 UT WOS:000500212000015 DA 2023-03-23 ER PT J AU Niu, FJ Gao, ZY Lin, ZJ Luo, J Fan, XW AF Niu, Fujun Gao, Zeyong Lin, Zhanju Luo, Jing Fan, Xingwen TI Vegetation influence on the soil hydrological regime in permafrost regions of the Qinghai-Tibet Plateau, China SO GEODERMA DT Article AB Soil hydrological processes are extremely complex in high-altitude regions and are recognized to have positive effects on soil quality, nutrient cycling, herbage yield, and runoff generation. However, soil hydrological processes have not been fully quantified in permafrost regions of the Qinghai-Tibet Plateau (QTP). To fill this gap, the soil water dynamics, soil water storage, soil infiltration processes, soil water retention and soil hydraulic conductivity were systematically monitored in different alpine ecosystems (alpine wet meadow (AWM), alpine meadow (AM), and alpine steppe (AS)). The results revealed that the soil water content was significantly higher in AWM soil in the shallow layer, while it was higher in AM soil in the deeper layer. Moreover, the response of soil water to rainfall was markedly more sensitive in AS soil than in AM and AWM soils. The average soil water storage amount reached 440 mm in the 0-100 cm soil interval of the AM, which was nearly 1.6-fold higher than that in the AS and 1.2-fold higher than that in the AWM. The existence of vegetation enhanced the soil infiltration rates in AWM and AM soils 1.3-fold and 1.5-fold, respectively, and decreased the soil infiltration rate 1.2-fold in AS soil. Nuclear magnetic resonance (NMR) results indicated that soil water in AS soil was mainly composed of capillary water and mobile water but was composed of bound water and capillary water in AWM soil and AM soil, respectively. The results from a redundancy analysis (RDA) demonstrated that the vegetation in the study region regulates the soil hydrological regime by altering the soil structure and soil biochemistry. Moreover, the mechanism of vegetation influence on soil hydrological processes suggests that the regional runoff generation will shift with the vegetation succession. The information obtained in this study may aid in the understanding of changes in the ecological environment and regional hydrological cycles under climate change. C1 [Niu, Fujun; Gao, Zeyong; Lin, Zhanju; Luo, Jing; Fan, Xingwen] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. [Fan, Xingwen] Univ Chinese Acad Sci, 19 Yuquan Rd, Beijing 100049, Peoples R China. RP Gao, ZY (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. EM gaozy@lzb.ac.cn TC 33 Z9 36 PD NOV 15 PY 2019 VL 354 AR 113892 DI 10.1016/j.geoderma.2019.113892 UT WOS:000486133300027 DA 2023-03-23 ER PT J AU Liu, FT Kou, D Abbott, BW Mao, C Chen, YL Chen, LY Yang, YH AF Liu, Futing Kou, Dan Abbott, Benjamin W. Mao, Chao Chen, Yongliang Chen, Leiyi Yang, Yuanhe TI Disentangling the Effects of Climate, Vegetation, Soil and Related Substrate Properties on the Biodegradability of Permafrost-Derived Dissolved Organic Carbon SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES DT Article; Early Access AB Dissolved organic carbon (DOC) plays an important role in permafrost carbon cycle. However, substantial uncertainties remain about what determines the biodegradability of permafrost-derived DOC and how the biodegradability varies between permafrost and active-layer soils at a regional scale. Here, we conducted an incubation experiment with DOC leached from permafrost and active-layer soils along a similar to 1,000-km permafrost transect on the Tibetan Plateau. Our results showed that permafrost-derived DOC had high biodegradability, with an average of 21.7% loss of DOC over a 28-day incubation. The biodegradability of DOC leached from permafrost soils was larger than or equal to that in active-layer within 72% of sampling sites. Our results also revealed that variation in DOC biodegradability in permafrost soils and its difference with that in active-layer soils were jointly determined by vegetation types, soil properties, and related DOC composition. The biodegradability of permafrost-derived DOC in alpine steppe and meadow was lower than that in swamp meadow. It also declined with the decreasing soil carbon: nitrogen ratio, increasing pH, clay content, DOC molecular weight, and its degradation degree. Similarly, the variability in the difference of DOC biodegradability between permafrost and active-layer soils also resulted from the differences of three types of above-mentioned factors between the two layers. These results suggest that permafrost thawing-induced DOC release could intensify permafrost carbon-climate feedback due to its vulnerability to microbial decomposition, with its impact depending on vegetation, soil, and substrate properties. C1 [Liu, Futing; Kou, Dan; Mao, Chao; Chen, Yongliang; Chen, Leiyi; Yang, Yuanhe] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. [Liu, Futing; Kou, Dan; Mao, Chao; Yang, Yuanhe] Univ Chinese Acad Sci, Beijing, Peoples R China. [Abbott, Benjamin W.] Brigham Young Univ, Dept Plant & Wildlife Sci, Provo, UT 84602 USA. RP Yang, YH (通讯作者)，Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China.; Yang, YH (通讯作者)，Univ Chinese Acad Sci, Beijing, Peoples R China. EM yhyang@ibcas.ac.cn TC 17 Z9 18 DI 10.1029/2018JG004944 EA NOV 2019 UT WOS:000495549100001 DA 2023-03-23 ER PT J AU Liu, YY Wang, Q Zhang, ZY Tong, LJ Wang, ZQ Li, JL AF Liu, Yangyang Wang, Qian Zhang, Zhaoying Tong, Linjing Wang, Zhenqian Li, Jianlong TI Grassland dynamics in responses to climate variation and human activities in China from 2000 to 2013 SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Improving our understanding of the impacts of climate variation and human activities on grassland dynamics is heightened by expectations that climate variation and human activities may induce grassland degradation. An accurate evaluation of the respective impacts of climate variation and human activities on grassland dynamics is crucial to understand the grassland degradation mechanism and to control the degraded grassland. In this study, net primary productivity (NPP) was selected as an indicator to reflect grassland dynamics. Meanwhile, the potential NPP (PNPP) and human-induced NPP (HNPP) calculated as the difference of PNPP and actual ANPP (ANPP) were used to assess the relative effects of climate variation and human activities on grassland NPP changes in China during 2000-2013. Results of grassland ANPP showed an overall increase than decrease in productivity (81.21% vs 18.79%) from 2000 to 2013. For the increase of ANPP, the relative contribution of climate variation and human activities to grassland NPP changes were 41.45% and 45.22%, respectively. Climate variation was the dominant factor that induced the increase in ANPP mainly in areas of Sichuan, Gansu, Ningxia and Inner Mongolia. An increase in Human-dominated ANPP mainly occurred in Tibet, Qinghai and Xinjiang. The decrease in ANPP is principally controlled by the effect of human activities than that of climate variation, especially in Inner Mongolia. Meanwhile, climate-dominated ANPP increase and human-dominated ANPP decrease mainly occurred in plain grassland, desert grassland and meadow across the six types of grasslands in China. Furthermore, in alpine sub-alpine meadow and alpine sub-alpine, while climate-dominated ANPP of grassland was found to be decreased, an increase in human-dominated ANPP was detected. The increase in precipitation and the implementation of ecological restoration programs were found to be effective in inducing the noticeable increased grassland ANPP since 2003. The findings of the current research recommend that the Chinese government should continue to implement the prohibiting graze policy across the country and extensively strengthen the implementation of the policy in Inner Mongolia and North Xinjiang, particularly in plain grassland, desert grassland and meadow. (C) 2019 Elsevier B.V. All rights reserved. C1 [Liu, Yangyang; Wang, Qian; Tong, Linjing; Li, Jianlong] Nanjing Univ, Sch Life Sci, Dept Ecol, Nanjing 210093, Jiangsu, Peoples R China. [Zhang, Zhaoying] Nanjing Univ, Jiangsu Prov Key Lab Geog Informat Sci & Technol, Int Inst Earth Syst Sci, Nanjing 210023, Jiangsu, Peoples R China. [Wang, Zhenqian] Lanzhou Univ, Sch Earth Sci, Lanzhou 730000, Gansu, Peoples R China. RP Zhang, ZY; Li, JL (通讯作者)，Nanjing Univ, Sch Life Sci, Dept Ecol, Xianlin Rd 163, Nanjing 210046, Jiangsu, Peoples R China. EM lijianlongnju@163.com; jlli2008@nju.edu.cn TC 61 Z9 76 PD NOV 10 PY 2019 VL 690 BP 27 EP 39 DI 10.1016/j.scitotenv.2019.06.503 UT WOS:000482549900004 DA 2023-03-23 ER PT J AU Cao, JJ Adamowski, JF Deo, RC Xu, XY Gong, YF Feng, Q AF Cao, Jianjun Adamowski, Jan F. Deo, Ravinesh C. Xu, Xueyun Gong, Yifan Feng, Qi TI Grassland Degradation on the Qinghai-Tibetan Plateau: Reevaluation of Causative Factors SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB In light of Harris (2010) finding insufficient evidence to assert a causal linkage between any of the seven previously proposed causative factors and grassland degradation on the Qinghai-Tibetan Plateau (QTP), more recent empirical studies on QTP grassland degradation were explored to ascertain whether, in fact, these factors are casually linked to grassland degradation. The mischaracterization of the underlying causes of grassland degradation among policymakers has and continues to be an obstacle to sustainable regional grassland management practices. Accumulating evidence suggests that privatization and sedentarization, small mammals, climate change, harsh environments, fragile soils, and overgrazing contribute to grassland degradation. However, neither obsolete livestock husbandry methods nor the recent conversion of rangelands to agriculture had a meaningful influence. Estimates of the total area of degraded grasslands and the establishment of grassland degradation criteria have not been properly addressed in the literature. Both omissions constitute the basis for investigating the causes of grassland degradation across the QTP and the adoption of measures to manage these grasslands sustainably. (C) 2019 The Authors. Published by Elsevier Inc. on behalf of The Society for Range Management. C1 [Cao, Jianjun; Xu, Xueyun; Gong, Yifan] Northwest Normal Univ, Coll Geog & Environm Sci, Lanzhou 730070, Gansu, Peoples R China. [Adamowski, Jan F.] McGill Univ, Dept Bioresource Engn, Fac Agr & Environm Sci, Ste Anne De Bellevue, PQ H9X 3V9, Canada. [Deo, Ravinesh C.] Univ Southern Queensland, Int Ctr Appl Climate Sci, Inst Agr & Environm, Sch Agr Computat & Environm Sci, Springfield, Qld 4300, Australia. [Feng, Qi] Chinese Acad Sci, Cold & Arid Reg Environm Engn Res Inst, Key Lab Ecohydrol Inland River Basin, Alashan Desert Ecohydrol Expt Res Stn, Lanzhou 73000, Gansu, Peoples R China. RP Feng, Q (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm Engn Res Inst, Key Lab Ecohydrol Inland River Basin, Alashan Desert Ecohydrol Expt Res Stn, Lanzhou 73000, Gansu, Peoples R China. EM qifeng@lzb.ac.cn TC 44 Z9 48 PD NOV PY 2019 VL 72 IS 6 BP 988 EP 995 DI 10.1016/j.rama.2019.06.001 UT WOS:000497319000014 DA 2023-03-23 ER PT J AU Chen, JJ Zhao, XN Zhang, HZ Qin, Y Yi, SH AF Chen, Jianjun Zhao, Xuning Zhang, Huizi Qin, Yu Yi, Shuhua TI Evaluation of the Accuracy of the Field Quadrat Survey of Alpine Grassland Fractional Vegetation Cover Based on the Satellite Remote Sensing Pixel Scale SO ISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION DT Article AB The fractional vegetation cover (FVC) data measured on the ground is the main source for the calibration and verification of FVC remote sensing inversion, and its accuracy directly affects the accuracy of remote sensing inversion results. However, the existing research on the evaluation of the accuracy of the field quadrat survey of FVC based on the satellite remote sensing pixel scale is inadequate, especially in the alpine grassland of the Qinghai-Tibet Plateau. In this paper, five different alpine grasslands were examined, the accuracy of the FVC obtained by the photography method was analyzed, and the influence of the number of samples on the field survey results was studied. First, the results show that the threshold method could accurately extract the vegetation information in the photos and obtain the FVC with high accuracy and little subjective interference. Second, the number of samples measured on the ground was logarithmically related to the accuracy of the FVC of the sample plot (p < 0.001). When the number of samples was larger, the accuracy of the FVC of the sample plot was higher and closer to the real value, and the stability of data also increased with the increase of the number of samples. Third, the average FVC of the measured quadrats on the ground was able to represent the FVC of the sample plot, but on the basis that there were enough measured quadrats. Finally, the results revealed that the degree of fragmentation reflecting the state of ground vegetation affects the acquisition accuracy of FVC. When the degree of fragmentation of the sample plot is higher, the number of samples needed to achieve the accuracy index is higher. Our results suggest that when obtaining the FVC on the satellite remote sensing pixel scale, the number of samples measured on the ground is an important factor affecting the accuracy, which cannot be ignored. C1 [Chen, Jianjun; Zhao, Xuning; Zhang, Huizi] Guilin Univ Technol, Coll Geomat & Geoinformat, 12 Jiangan Rd, Guilin 541004, Peoples R China. [Chen, Jianjun] Guangxi Key Lab Spatial Informat & Geomat, 12 Jiangan Rd, Guilin 541004, Peoples R China. [Qin, Yu] Chinese Acad Sci, State Key Lab Cryospher Sci, Northwest Inst Ecoenvironm & Resources, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. [Yi, Shuhua] Nantong Univ, Inst Fragile Ecosyst & Environm, 999 Tongjing Rd, Nantong 226007, Peoples R China. [Yi, Shuhua] Nantong Univ, Sch Geog Sci, 999 Tongjing Rd, Nantong 226007, Peoples R China. RP Yi, SH (通讯作者)，Nantong Univ, Inst Fragile Ecosyst & Environm, 999 Tongjing Rd, Nantong 226007, Peoples R China.; Yi, SH (通讯作者)，Nantong Univ, Sch Geog Sci, 999 Tongjing Rd, Nantong 226007, Peoples R China. EM chenjj@lzb.ac.cn; zxn@glut.edu.cn; gjian@glut.edu.cn; qiny@lzb.ac.cn; yis@lzb.ac.cn TC 8 Z9 10 PD NOV PY 2019 VL 8 IS 11 AR 497 DI 10.3390/ijgi8110497 UT WOS:000502272600031 DA 2023-03-23 ER PT J AU Hou, XY Liu, SL Zhao, S Dong, SK Sun, YX Beazley, R AF Hou, Xiaoyun Liu, Shiliang Zhao, Shuang Dong, Shikui Sun, Yongxiu Beazley, Robert TI The alpine meadow around the mining areas on the Qinghai-Tibetan Plateau will degenerate as a result of the change of dominant species under the disturbance of open-pit mining SO ENVIRONMENTAL POLLUTION DT Article AB Mining is well-known as one of the most aggressive human disturbances leading to massive and irreversible damages to natural ecosystems. However, the influence mechanisms of open-pit mining on plant communities and soil properties of alpine meadow on the Qinghai-Tibetan plateau are not well understood. In this study, we used structural equation modeling (SEM) to study the influence mechanisms in the disturbed areas of the Qulong copper mine. Our results revealed that the soil parameters of alpine meadow have been significantly changed by mining activities. SEM results showed that Plantago depressa Willd. was more suitable for growing in current soil conditions due to its tolerance to heavy metals than other dominant species, which meant that it would substitute the current two dominant species (Kobresia myosuroides (Villars) Fiori and Blysmus sinocompressus Tang et Wang) in the future and become the most important dominant species in the study area. Unfortunately, the Shannon-Wiener index, Alatalo evenness index and M-Gordon stability index are relatively low in the plot with Plantago depressa Willd. as the dominant species. In a word, the fragile alpine meadow ecosystem may degenerate in the future due to plants and soil disturbed by mining activities. Further, eight targeted recommendations were proposed to protect alpine meadow on the Qinghai Tibetan plateau. (C) 2019 Elsevier Ltd. All rights reserved. C1 [Hou, Xiaoyun; Liu, Shiliang; Zhao, Shuang; Dong, Shikui; Sun, Yongxiu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Beazley, Robert] Cornell Univ, Dept Nat Resources, Coll Agr & Life Sci, Femow Hall 302, Ithaca, NY 14853 USA. RP Liu, SL (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM shiliangliu@bnu.edu.cn TC 8 Z9 9 PD NOV PY 2019 VL 254 AR 113111 DI 10.1016/j.envpol.2019.113111 PN B UT WOS:000488887600069 DA 2023-03-23 ER PT J AU Li, GR Li, XL Li, JF Chen, WT Zhu, HL Zhao, JY Hu, XS AF Li, Guorong Li, Xilai Li, Jinfang Chen, Wenting Zhu, Haili Zhao, Jianyun Hu, Xiasong TI Influences of Plateau Zokor Burrowing on Soil Erosion and Nutrient Loss in Alpine Meadows in the Yellow River Source Zone of West China SO WATER DT Article AB Plateau zokors (Eospalax baileyi) are an agent actively involved in causing soil erosion and meadow degradation in the Yellow River Source Zone of West China. This study aims to quantify the amount of soil and nutrient loss from zokor mounds in relation to slope gradient and rainfall intensity, and to assess the amount of soil loss in zokor-infested areas compared with healthy meadows in Henan County, Qinghai Province. The results showed that zokor mounds were gradually lowered at a rate of 1.8-3.9 cm h(-1). Soil loss occurred two min after the rain began, reaching the maximum level during the first 20 min. The rate of soil loss and nutrient loss increased with the rainfall intensity and slope gradient. When the rainfall intensity rose from 5 to 10 mm h(-1), and from 10 to 15 mm h(-1), the total soil loss on 10 degrees slopes increased by 2.5 times and 3.9 times, respectively, and soil nutrient loss increased by 1.7 times and 2.7 times, respectively. As the slope gradient steepened to 20 degrees, the corresponding figures were 2.8 times and 4.3 times for total soil loss, and 1.8 times and 2.9 times, respectively, for soil nutrient loss. When the slope rose to 30 degrees, the soil loss increased by 3.0 and 4.5 times, and the soil nutrient loss increased by 1.8 times and 3.1 times, respectively. There was a power function between soil loss and surface runoff (S = 0.2371Q(2.2307), R-2 = 0.9529). The soil was eroded at a rate of 256.6 g m(-2) h(-1) from zokor mounds, 17.7 times higher than in intact meadows, and 1.8 times higher than in partially recovered meadows. Most of the eroded soils had a mean diameter of 0-1.2 mm. It is recommended that artificial control of plateau zokors should be implemented, together with other ecological restoration measures to restrain the soil erosion problem caused by zokor activities. C1 [Li, Guorong; Li, Xilai; Hu, Xiasong] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. [Li, Guorong; Li, Jinfang; Chen, Wenting; Zhu, Haili; Zhao, Jianyun; Hu, Xiasong] Qinghai Univ, Geol Engn Dept, Xining 810016, Qinghai, Peoples R China. [Li, Guorong] Key Lab Cenozo Resource & Environm North Margin T, Xining 810016, Qinghai, Peoples R China. [Li, Xilai] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Qinghai, Peoples R China. RP Li, XL (通讯作者)，Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China.; Li, XL (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Qinghai, Peoples R China. EM qdliguorong@163.com; xilai-li@163.com; qdlijinfang@163.com; chenwt77@hotmail.com; qdzhuhaili@163.com; zjyunh@163.com; Huxiasong@sina.com TC 6 Z9 6 PD NOV PY 2019 VL 11 IS 11 AR 2258 DI 10.3390/w11112258 UT WOS:000502264500060 DA 2023-03-23 ER PT J AU Liu, YY Zhang, ZY Tong, LJ Khalifa, M Wang, Q Gang, CC Wang, ZQ Li, JL Sun, ZG AF Liu, Yangyang Zhang, Zhaoying Tong, Linjing Khalifa, Muhammad Wang, Qian Gang, Chengcheng Wang, Zhenqian Li, Jianlong Sun, Zhengguo TI Assessing the effects of climate variation and human activities on grassland degradation and restoration across the globe SO ECOLOGICAL INDICATORS DT Article AB While quantitative assessment of ecosystems degradation is quite addressed in the literature, quantitatively separating the relative contribution of climate variation and human activities to grassland ecosystem degradation is still limited, although well recognized as a key knowledge for a better understanding of the degradation mechanisms and for more efficient control of degradation processes. In this study, actual net primary productivity (ANPP) was selected as an indicator to investigate the grassland dynamics from 2000 to 2013. In addition, potential NPP (PNPP) and human-induced NPP (HNPP), which was calculated as the difference between PNPP and ANPP, were used to differentiate the relative impacts of climate variation and human activities on grassland degradation/restoration, respectively. Results showed that 60.94% of the total global area of grassland experienced restoration over the study period, with an increase in NPP by 1864.81 Tg C across the globe. The restored areas induced by climate variation and human activities accounted for 45.73% and 34.99% with an increases in NPP by 852.75 Tg C and 652.50 Tg C, respectively. By contrast, nearly 39.06% of the global grassland area experienced degradation. This degradation was associated with a noticeable decrease in ANPP by 325.53 Tg C. While 45.45% of the degraded grassland areas were influenced by climate variation, human activities were accounted for around 40.11% of this degradation. The relative effect of the two factors (i.e. climate variation and human activities) on grassland changes was found to vary greatly among the studied six continents. While human activities exerted larger impacts than climate variation on grassland degradation in North America and Europe, climate variation was the dominant factor for grassland restoration in Asia, Europe, Oceania and North America, which can be mainly attributed to the increase in precipitation during the study period. The findings of the current study improved our understanding of the relative impacts of climate variation and human activities on grassland degradation and restoration at the global scale. C1 [Liu, Yangyang; Tong, Linjing; Wang, Qian; Li, Jianlong] Nanjing Univ, Sch Life Sci, Dept Ecol, Nanjing 210093, Jiangsu, Peoples R China. [Zhang, Zhaoying] Nanjing Univ, Int Inst Earth Syst Sci, Jiangsu Prov Key Lab Geog Informat Sci & Technol, Nanjing 210023, Jiangsu, Peoples R China. [Khalifa, Muhammad] TH Koln Cologne Univ Appl Sci, Inst Technol & Resources Management Trop & Subtro, D-50679 Cologne, Germany. [Khalifa, Muhammad] Univ Cologne, Dept Geog, Albertus Magnus Pl, D-50923 Cologne, Germany. [Gang, Chengcheng] Northwest A&F Univ, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. [Wang, Zhenqian] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Gansu, Peoples R China. [Sun, Zhengguo] Nanjing Agr Univ, Coll Prataculture Sci, Nanjing 210095, Jiangsu, Peoples R China. RP Li, JL; Sun, ZG (通讯作者)，Nanjing Univ, Sch Life Sci, Dept Ecol, Xianlin Rd 163, Nanjing 210046, Jiangsu, Peoples R China. EM jlli2008@nju.edu.cn TC 51 Z9 57 PD NOV PY 2019 VL 106 AR 105504 DI 10.1016/j.ecolind.2019.105504 UT WOS:000490577900069 DA 2023-03-23 ER PT J AU Tian, MY Yang, XK Ran, LS Su, YR Li, LY Yu, RH Hu, HZ Lu, XX AF Tian, Mingyang Yang, Xiankun Ran, Lishan Su, Yuanrong Li, Lingyu Yu, Ruihong Hu, Haizhu Lu, Xi Xi TI Impact of Land Cover Types on Riverine CO2 Outgassing in the Yellow River Source Region SO WATER DT Article AB Under the context of climate change, studying CO2 emissions in alpine rivers is important because of the large carbon storage in these terrestrial ecosystems. In this study, riverine partial pressure of CO2 (pCO(2)) and CO2 emission flux (FCO2) in the Yellow River source region (YRSR) under different landcover types, including glaciers, permafrost, peatlands, and grasslands, were systematically investigated in April, June, August, and October 2016. Relevant chemical and environmental parameters were analyzed to explore the primary controlling factors. The results showed that most of the rivers in the YRSR were net CO2 source, with the pCO(2) ranging from 181 to 2441 mu atm and the FCO2 ranging from -50 to 1574 mmol m(-2) d(-1). Both pCO(2) and FCO2 showed strong spatial and temporal variations. The highest average FCO2 was observed in August, while the lowest average was observed in June. Spatially, the lowest FCO2 were observed in the permafrost regions while the highest FCO2 were observed in peatland. By integrating seasonal changes of the water surface area, total CO2 efflux was estimated to be 0.30 Tg C year(-1). This indicates that the YRSR was a net carbon source for the atmosphere, which contradicts previous studies that conclude the YRSR as a carbon sink. More frequent measurements of CO2 fluxes, particularly through several diel cycles, are necessary to confirm this conclusion. Furthermore, our study suggested that the riverine dissolved organic carbon (DOC) in permafrost (5.0 +/- 2.4 mg L-1) is possibly derived from old carbon released from permafrost melting, which is equivalent to that in peatland regions (5.1 +/- 3.7 mg L-1). The degradation of DOC may have played an important role in supporting riverine CO2, especially in permafrost and glacier-covered regions. The percent coverage of corresponding land cover types is a good indicator for estimating riverine pCO(2) in the YRSR. In view of the extensive distribution of alpine rivers in the world and their sensitivity to climate change, future studies on dynamics of stream water pCO(2) and CO2 outgassing are strongly needed to better understand the global carbon cycle. C1 [Tian, Mingyang; Su, Yuanrong; Li, Lingyu; Yu, Ruihong; Hu, Haizhu; Lu, Xi Xi] Inner Mongolia Univ, Sch Ecol & Environm, Inner Mongolia Key Lab River & lAke Ecol, Hohhot 010021, Peoples R China. [Tian, Mingyang; Yang, Xiankun] Guangzhou Univ, Sch Geog Sci, Guangzhou 510006, Guangdong, Peoples R China. [Ran, Lishan] Univ Hong Kong, Dept Geog, Hong Kong, Peoples R China. [Lu, Xi Xi] Natl Univ Singapore, Dept Geog, Singapore 117570, Singapore. RP Hu, HZ; Lu, XX (通讯作者)，Inner Mongolia Univ, Sch Ecol & Environm, Inner Mongolia Key Lab River & lAke Ecol, Hohhot 010021, Peoples R China.; Lu, XX (通讯作者)，Natl Univ Singapore, Dept Geog, Singapore 117570, Singapore. EM tianmingyang1992@163.com; yangxk@gzhu.edu.cn; lsran@hku.hk; suyuanrong@hotmail.com; 18504846955@163.com; rhyu@imu.edu.cn; haizhuhu@163.com; geoluxx@nus.edu.sg TC 6 Z9 6 PD NOV PY 2019 VL 11 IS 11 AR 2243 DI 10.3390/w11112243 UT WOS:000502264500045 DA 2023-03-23 ER PT J AU Xu, HP Zhang, J Pang, XP Wang, Q Zhang, WN Wang, J Guo, ZG AF Xu, Hai Peng Zhang, Jing Pang, Xiao Pan Wang, Qian Zhang, Wen Na Wang, Juan Guo, Zheng Gang TI Responses of plant productivity and soil nutrient concentrations to different alpine grassland degradation levels SO ENVIRONMENTAL MONITORING AND ASSESSMENT DT Article AB Although grassland degradation simultaneously affects plant productivity and soil nutrient concentrations, the relationship between plant productivity and soil nutrient concentrations during the process of grassland degradation is not yet well documented. A 4-year survey in the Qinghai-Tibetan Plateau was conducted to simultaneously investigate the relationships between plant productivity and soil nutrient concentrations in an alpine grassland at an overall degradation level and individual degradation levels. Our results showed that the total plant, sedge, and forb biomasses decreased, whereas the grass and legume biomasses first increased and then decreased as the level of alpine grassland degradation increased. Soil organic carbon (C), total nitrogen (N), total phosphorus (P), available N, and available P concentrations also decreased with the increase in degradation level. Our results also showed that plant productivity was positively correlated with soil nutrient concentrations (soil organic C, total T, total P, available N, available P) at an overall degradation level, whereas plant productivity was positively correlated with only the soil organic C concentration at each degradation level. Our findings suggested that the alpine grassland degradation conditions had different effects on the plant productivity of four functional groups (sedges, grasses, legumes, forbs) and affected the relationship between plant productivity and soil nutrient concentrations. C1 [Xu, Hai Peng; Zhang, Jing; Pang, Xiao Pan; Wang, Qian; Zhang, Wen Na; Wang, Juan; Guo, Zheng Gang] Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, State Key Lab Grassland Agroecosyst, Minist Agr & Rural Affairs,Coll Pastoral Agr Sci, Lanzhou 730020, Gansu, Peoples R China. RP Guo, ZG (通讯作者)，Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, State Key Lab Grassland Agroecosyst, Minist Agr & Rural Affairs,Coll Pastoral Agr Sci, Lanzhou 730020, Gansu, Peoples R China. EM guozhg@lzu.edu.cn TC 10 Z9 13 PD NOV PY 2019 VL 191 IS 11 AR 678 DI 10.1007/s10661-019-7877-2 UT WOS:000493104900005 DA 2023-03-23 ER PT J AU Yu, LF Chen, Y Sun, WJ Huang, Y AF Yu, Lingfei Chen, Yue Sun, Wenjuan Huang, Yao TI Effects of grazing exclusion on soil carbon dynamics in alpine grasslands of the Tibetan Plateau SO GEODERMA DT Article AB Globally, excessive grazing is identified as one of the key disturbances leading to grassland degradation and soil carbon (C) loss. Grazing exclusion has been proposed as an effective practice to restore degraded grasslands and to promote C sequestration. However, there is still little knowledge about how soil C changes with grazing exclusion in high-altitude alpine ecosystems with very cold climates. We synthesized data from 63 sites in the literature and 15 sites in a field sampling and investigated the dynamics of soil C stocks following grazing exclusion in alpine grasslands of the Tibetan Plateau. The results showed that the soil C stock increased with grazing exclusion at most sites, with average C sequestration rates of 0.84, 0.58, and 0.49 Mg ha(-1) yr(-1) in the soil layers of 0-10, 10-20, and 20-30 cm, respectively. Based on these results, if 60 million ha of the grasslands on Tibetan Plateau were excluded from grazing livestock by 2020 according to the national plan, then approximately 0.11 Pg C yr(-1) would be sequestered in the soil which equates to about 4.4% of fossil fuel and cement CO2 emissions in China in 2013. Generally, the rates of soil C increase exhibited a declining pattern with increasing years of grazing exclusion, with a significant decrease occurring after ten years of grazing exclusion. Of the factors examined, the rates of absolute and relative soil C change were both positively related to mean annual precipitation but negatively related to the year of grazing exclusion and initial soil C stock, respectively. The rates of soil C changes increased linearly with those of N change, and no matter how soil C changed (whether it increased or decreased), soil C:N ratios remained stable over the years of grazing exclusion. Our results implied that grazing exclusion is beneficial for soil C sequestration in degraded alpine grassland, especially in humid areas. Moreover, the intrinsic increase in N could keep up with the pace of soil C changes and would sustain soil C sequestration during the recovery process. C1 [Yu, Lingfei; Chen, Yue; Sun, Wenjuan; Huang, Yao] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. RP Yu, LF (通讯作者)，Chinese Acad Sci, Inst Bot, 20 Nanxincun, Beijing 100093, Peoples R China. EM yulf@ibcas.ac.cn TC 36 Z9 39 PD NOV 1 PY 2019 VL 353 BP 133 EP 143 DI 10.1016/j.geoderma.2019.06.036 UT WOS:000482513900014 DA 2023-03-23 ER PT J AU Wei, D Zhao, H Huang, L Qi, YH Wang, XD AF Wei, Da Zhao, Hui Huang, Lin Qi, Yahui Wang, Xiaodan TI Feedbacks of Alpine Wetlands on the Tibetan Plateau to the Atmosphere SO WETLANDS DT Article AB The alpine wetlands of the Tibetan Plateau (TP) contribute 30%-40% of China's natural wetlands, and they are experiencing changes in climate, i.e. warming of 0.26 degrees C 10 yr(-1) (since the 1950s), as well as considerable human impacts. Consequently, alpine wetland extent show strong response to these impacts in most part, a reduction since the 1970s, followed by a recovery since the 2000s. In the eastern TP, they suffered stronger human regulations in Zoige mires, i.e. decades' drainage and recent restoration. These alpine wetlands have long been considered as a vital CH4 source, while inventories and model simulations estimated these wetlands emit roughly 1 Tg CH4-C yr(-1) and predicted an increase due to increased temperature and recovery of wetland extent. The alpine wetlands are generally a CO2 sink of roughly 15.8 Tg CO2 yr(-1), mitigating half of their emitted CH4, and satellite-based observations of vegetation greening have observed that their plants took more CO2 from the atmosphere. Furthermore, the alpine wetlands provide a biophysical cooling effect, due to higher evaporative energy loss during early growing seasons. Variations in both climate changes and human influences have been well documented and indicate that these alpine wetlands provide vital feedbacks to the climate. C1 [Wei, Da; Zhao, Hui; Qi, Yahui; Wang, Xiaodan] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, 9,Sect 4,Renminnanlu Rd, Chengdu 610041, Sichuan, Peoples R China. [Huang, Lin] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Qi, Yahui] Chinese Acad Sci, Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Wang, XD (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, 9,Sect 4,Renminnanlu Rd, Chengdu 610041, Sichuan, Peoples R China. EM wxd@imde.ac.cn TC 9 Z9 11 PD AUG PY 2020 VL 40 IS 4 BP 787 EP 797 DI 10.1007/s13157-019-01220-4 EA OCT 2019 UT WOS:000492938000001 DA 2023-03-23 ER PT J AU Peng, F Xue, X You, QG Sun, J Zhou, J Wang, T Tsunekawa, A AF Peng, Fei Xue, Xian You, Quangang Sun, Jian Zhou, Jun Wang, Tao Tsunekawa, Atsushi TI Change in the trade-off between aboveground and belowground biomass of alpine grassland: Implications for the land degradation process SO LAND DEGRADATION & DEVELOPMENT DT Article AB Alpine grassland on the Qinghai-Tibet Plateau has been degrading in recent decades. A better understanding of biomass trade-off (biomass allocation between aboveground [AGB] and belowground [BGB]) change with alpine grassland degradation could uncover the degradation processes and its underlying mechanisms. We surveyed the plant and soil characteristics of alpine meadow (AM) and alpine steppe (AS) at varying degradation levels on the plateau. In the AM, the AGB was only reduced when very severely degraded, but the BGB declined at any level of degradation. In the AS, the AGB showed no significant difference in the slightly, moderately, and severely degraded levels, and the AGB only significantly declined in the very severely degraded, whereas the BGB was nonsignificantly higher in the slightly degraded and gradually declined when the levels changed from slightly to very severely degraded. In the undegraded grasslands, the biomass trade-off was towards AGB and BGB in AS and AM, respectively. With degradation, the biomass trade-off shifted from AGB to BGB at the slightly degraded levels and then gradually reached zero trade-off at the very severely degraded level in the AS. In the AM, the trade-off gradually reached zero as moderately degraded progressed to very severely degraded level. The change in plant community composition and bulk density affected the biomass trade-off change independently with AM degradation, whereas only soil moisture, soil nitrogen, and soil pH interactively influenced the biomass trade-off change with AS degradation. Our results suggest different AGB and BGB change processes and mechanisms with AS and AM degradation. C1 [Peng, Fei; Xue, Xian; You, Quangang; Wang, Tao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resource, Key Lab Desert & Desertificat, Lanzhou 730000, Gansu, Peoples R China. [Peng, Fei; Tsunekawa, Atsushi] Tottori Univ, Int Platform Dryland Res & Educ, Tottori 6800001, Japan. [Peng, Fei; Tsunekawa, Atsushi] Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. [Sun, Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Zhou, Jun] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Sichuan, Peoples R China. RP Peng, F (通讯作者)，Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. EM pengfei@lzb.ac.cn TC 31 Z9 34 PD JAN 15 PY 2020 VL 31 IS 1 BP 105 EP 117 DI 10.1002/ldr.3432 EA OCT 2019 UT WOS:000492735100001 DA 2023-03-23 ER PT J AU Wang, XJ Wang, Q Jin, L Sun, L Wang, Q Zhang, L Chen, YL AF Wang, Xiaojuan Wang, Qiang Jin, Liang Sun, Li Wang, Qian Zhang, Liang Chen, Yinglong TI Arbuscular mycorrhizal fungi in the rhizosphere soil of poisonous plants depressed the growth of pasture grasses in the Tibetan Plateau Alpine meadow SO ECOSYSTEM HEALTH AND SUSTAINABILITY DT Article AB In order to explore the influence of arbuscular mycorrhizal (AM) fungi in the rhizosphere of poisonous plants on the neighboring pasture grasses in the Tibetan Plateau Alpine meadow ecosystem, rhizosphere soils were collected from eight different poisonous plants in degraded grasslands and one from pasture grass in non-degraded grasslands (CK). The collected soils were used as inocula to assess the influence of indigenous AM fungi on the growth of two typical pasture grass species,?Elymus nutans?and?Poa pratensis, in a bioassay experiment. Five growth parameters and two AM parameters were determined. The mycorrhizal responsiveness and the importance value were calculated. Significant differences between the eight poisonous plants and CK were observed. Compared to CK, rhizosphere soil from the eight poisonous plants had lower AM fungal spore densities. The growth of?E. nutans?and?P. pratensis?seedlings was depressed with the inoculation from poisonous plants rhizosphere soil. This study demonstrated that the presence of poisonous plants with grassland degradation altered inherent AM fungal community abundance, and could exert inhibition effects on the growth of pasture grasses. It may attribute to discover the important role of rhizosphere soil of different poisonous plants to AM fungal community on the Alpine meadow. C1 [Wang, Xiaojuan; Jin, Liang] Shanghai Sci & Technol Museum, Shanghai Nat Hist Museum, Nat Hist Res Ctr, Shanghai, Peoples R China. [Wang, Qiang; Sun, Li; Wang, Qian; Zhang, Liang] Lanzhou Univ, Sch Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou, Gansu, Peoples R China. [Chen, Yinglong] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess, Yangling, Shaanxi, Peoples R China. [Chen, Yinglong] Chinese Acad Sci, Inst Soil & Water Conservat, Yangling, Shaanxi, Peoples R China. [Chen, Yinglong] Univ Western Australia, Sch Earth & Environm, Perth, WA, Australia. [Chen, Yinglong] Univ Western Australia, UWA Inst Agr, Perth, WA, Australia. RP Wang, XJ (通讯作者)，Shanghai Sci & Technol Museum, Nat Hist Res Ctr, 2000 Century Ave, Shanghai 200127, Peoples R China. EM wangxj@sstm.org.cn TC 2 Z9 4 PD JAN 2 PY 2019 VL 5 IS 1 BP 226 EP 236 DI 10.1080/20964129.2019.1673215 EA OCT 2019 UT WOS:000490966900001 DA 2023-03-23 ER PT J AU Hou, YH Chen, Y Chen, X He, KY Zhu, B AF Hou, Yanhui Chen, Ying Chen, Xiao He, Keyi Zhu, Biao TI Changes in soil organic matter stability with depth in two alpine ecosystems on the Tibetan Plateau SO GEODERMA DT Article AB Soil organic carbon (SOC) decomposition can potentially feedback to climate change. However, the biotic, abiotic and inherent factors controlling the stability of soil carbon, and changes in these factors with soil depth, remain poorly understood. In this study, we combined a number of complementary methods to quantify the biological, thermal, chemical, molecular and isotopic indices of soil organic matter (SOM) stability along the soil profile (0-70 cm) in two contrasting alpine ecosystems (meadow and shrubland) on the Tibetan Plateau. Firstly, we conducted an aerobic lab-incubation experiment on root-free, sieved soils. The number of days to respire 5% of initial SOC, a biological index of SOM stability, decreased with soil depth. Moreover, the temperature at which half of SOM mass loss (TG-T50), a thermal index of SOM stability, increased with soil depth. Additionally, hot-water extractable organic carbon (HWEOC) per gram SOC, a chemical index of SOM stability, showed weak (meadow) and little (shrubland) declining trend with depth. Further, we used Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy to characterize the molecular composition of SOM. The index of recalcitrance of FTIR spectra and the combined index of aliphaticity and aromaticity of NMR spectra both increased with depth, suggesting that the molecular composition of SOM was more complex with increasing depth. Finally, the isotopic values of SOM (C-13 and N-15) and the C-14-based SOC turnover time both increased with depth, indicating that the isotopic indices of SOM stability also increased with depth. Overall, our results suggest that the thermal, chemical, molecular and isotopic indices of SOM stability were mutually correlated and all showed increasing trend with increasing soil depth in the two alpine ecosystems, although the biological index (as measured by aerobic incubation of root-free sieved soils) showed the opposite results. C1 [Hou, Yanhui; Chen, Ying; Chen, Xiao; He, Keyi; Zhu, Biao] Peking Univ, Minist Educ, Key Lab Earth Surface Proc, Inst Ecol,Coll Urban & Environm Sci, Beijing 100871, Peoples R China. RP Zhu, B (通讯作者)，Peking Univ, Minist Educ, Key Lab Earth Surface Proc, Inst Ecol,Coll Urban & Environm Sci, Beijing 100871, Peoples R China. EM biaozhu@pku.edu.cn TC 32 Z9 36 PD OCT 1 PY 2019 VL 351 BP 153 EP 162 DI 10.1016/j.geoderma.2019.05.034 UT WOS:000474495700015 DA 2023-03-23 ER PT J AU Zhang, WJ Xue, X Peng, F You, QG Hao, AH AF Zhang, Wenjuan Xue, Xian Peng, Fei You, Quangang Hao, Aihua TI Meta-analysis of the effects of grassland degradation on plant and soil properties in the alpine meadows of the Qinghai-Tibetan Plateau SO GLOBAL ECOLOGY AND CONSERVATION DT Article AB Alpine meadows on the Qinghai-Tibetan plateau (QTP) are particularly important for both ecosystem functioning and pastoral livelihoods, but they have been severely degraded in the last several decades. There have been numerous studies on the responses of plants and soils to alpine meadow degradation across the region, but they are mostly focused on single sites and are incapable of determining a general response pattern of plants and soils to degradation on the QTP. A meta-analysis including 61 individual published studies was conducted to examine the biotic and abiotic characteristics in slightly (LDAM), moderately (MDAM), severely (SDAM), and very severely degraded alpine meadows (VDAM). The results showed that the aboveground biomass (AGB) significantly decreased (P < 0.01) by 23.17%, 31.85%, 47.24%, and 66.66% in the LDAM, MDAM, SDAM, and VDAM compared with that in nondegraded alpine meadows (NDAM), respectively. The belowground biomass (BGB) did not change in the LDAM but began to decrease with the MDAM. The AGBs of graminoids significantly decreased in all degraded-level meadows, and sedges significantly decreased from MDAM to VDAM, whereas the AGBs of forbs significantly increased except in the VDAM. The Shannon-wiener index did not change until the VDAM. Soil organic matter (SOM) declined starting with the LDAM, and the magnitude of the decrease increased with degradation severity. The change in total nitrogen (TN) was similar to the change in the SOM. Significant available nitrogen (AN) decrease began with the MDAM and significant (P < 0.05) available potassium (AK) decrease only occurred at depth of 0.0-0.1m in the SDAM and the VDAM. Soil moisture (SM) showed a significant decrease, whereas soil bulk density (BD) increased in the degraded alpine meadow. The response of AGB was significantly correlated with the changes in SOM and TN only in the SDAM and VDAM, whereas the response of BGB was significantly correlated with the changes in SOM and TN for all degraded stages. In the LDAM and MDAM, SOM and TN mainly came from the dense rooting of the turf layer, and the changes of SOM and TN thus had no correlation with AGB. However, in the SDAM and VDAM, SOM and TN mainly came from AGB and BGB, and the changes of SOM and TN were thus significantly correlated with AGB and BGB. Our results indicate that biological and biochemical processes regulate the plant and soil changes in LDAM and MDAM and that physical processes such as water and wind erosion might be responsible for the changes in plants and soils in SDAM and VDAM. Therefore, restoration strategies should be based on the processes and stages of alpine meadow degradation. (c) 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). C1 [Zhang, Wenjuan; Xue, Xian; Peng, Fei; You, Quangang; Hao, Aihua] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. [Zhang, Wenjuan; Hao, Aihua] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Peng, Fei] Tottori Univ, Int Platform Dryland Res & Educ, Arid Land Res Ctr, Hamasaka 1390, Tottori 6800001, Japan. RP Zhang, WJ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. EM zhangwenjuan@lzb.ac.cn TC 39 Z9 44 PD OCT PY 2019 VL 20 AR e00774 DI 10.1016/j.gecco.2019.e00774 UT WOS:000498226800083 DA 2023-03-23 ER PT J AU Zhang, ZC Hou, G Liu, M Wei, TX Sun, J AF Zhang Zhen-chao Hou Ge Liu Miao Wei Tian-xing Sun Jian TI Degradation induces changes in the soil C:N:P stoichiometry of alpine steppe on the Tibetan Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Due to the Tibetan Plateau's unique high altitude and low temperature climate conditions, the region's alpine steppe ecosystem is highly fragile and is suffering from severe degradation under the stress of increasing population, overgrazing, and climate change. The soil stoichiometry, a crucial part of ecological stoichiometry, provides a fundamental approach for understanding ecosystem processes by examining the relative proportions and balance of the three elements. Understanding the impact of degradation on the soil stoichiometry is vital for conservation and management in the alpine steppe on the Tibetan Plateau. This study aims to examine the response of soil stoichiometry to degradation and explore the underlying biotic and abiotic mechanisms in the alpine steppe. We conducted a field survey in a sequent degraded alpine steppe with seven levels in Northern Tibet. The plant species, aboveground biomass, and physical and chemical soil properties such as the moisture content, temperature, pH, compactness, total carbon (C), total nitrogen (N), and total phosphorus (P) were measured and recorded. The results showed that the contents of soil C/N, C/P, and N/P consistently decreased along intensifying degradation gradients. Using regression analysis and a structural equation model (SEM), we found that the C/N, C/P, and N/P ratios were positively affected by the soil compactness, soil moisture content and species richness of graminoids but negatively affected by soil pH and the proportion of aboveground biomass of forbs. The soil temperature had a negative effect on the C/N ratio but showed positive effect on the C/P and N/P ratios. The current study shows that degradation-induced changes in abiotic and biotic conditions such as soil warming and drying, which accelerated the soil organic carbon mineralization, as well as the increase in the proportion of forbs, which were difficult to decompose and input less organic carbon into soil, resulted in the decreases in soil C/N, C/P, and N/P contents to a great extent. Our results provide a sound basis for sustainable conservation and management of the alpine steppe. C1 [Zhang Zhen-chao; Wei Tian-xing] Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing 100083, Peoples R China. [Zhang Zhen-chao; Hou Ge; Liu Miao; Sun Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. [Sun Jian] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China. [Sun Jian] Rutgers State Univ, Sch Environm & Biol Sci, Dept Ecol Evolut & Nat Resources, New Brunswick, NJ 08901 USA. RP Wei, TX (通讯作者)，Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing 100083, Peoples R China.; Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China.; Sun, J (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China.; Sun, J (通讯作者)，Rutgers State Univ, Sch Environm & Biol Sci, Dept Ecol Evolut & Nat Resources, New Brunswick, NJ 08901 USA. EM zhenchaozhang0626@163.com; houge0415@163.com; liumiao@igsnrr.ac.cn; weitx@bjfu.edu.cn; sunjian@igsnrr.ac.cn TC 21 Z9 26 PD OCT PY 2019 VL 16 IS 10 BP 2348 EP 2360 DI 10.1007/s11629-018-5346-y UT WOS:000489956000011 DA 2023-03-23 ER PT J AU Ma, L Xu, SX Liu, HJ Xu, TW Hu, LY Zhao, N Han, XP Zhang, XL AF Ma, Li Xu, Shixiao Liu, Hongjin Xu, Tianwei Hu, Linyong Zhao, Na Han, Xueping Zhang, Xiaoling TI Yak rumen microbial diversity at different forage growth stages of an alpine meadow on the Qinghai-Tibet Plateau SO PEERJ DT Article AB The rumen microbiota of ruminants plays a vital role in fiber digestion, and environmental factors affect its community structure. The yak (Bos grunniens) is the main livestock species that inhabits the Qinghai-Tibet Plateau (QTP) at regions located at high-altitude of 3,000-5,000 m. This work investigated the rumen bacterial community of yak that grazed on the QTP during the whole year to evaluate the relationship between the rumen bacterial community and the nutrient composition of forage plant at three stages. In this study, the diversity of the rumen prokaryotic community composition was monitored in 10 full-grazing yak in an alpine meadow of the QTP. The nutrient composition of three forage growth stages was determined: re-green stage (REGY), grassy stage (GY), and withered stage (WGY). High-throughput sequencing of bacterial 16S rRNA gene was used. The results showed that the nutritive composition of the alpine meadow changed with the seasons: crude protein (CP) (13.22%) was high in forage during REGY (spring), while neutral detergent fiber (NDF) (59.00%) was high during WGY (winter). Microbial diversity and richness were highest during REGY and the average number of operational taxonomic units from 30 samples was 4,470. The microbial composition was dominated by members of Bacteroidetes (51.82%), followed by Firmicutes (34.08%), and the relative microbial abundance changed in the three forage growth stages. Unweighted UniFrac distance PcoA showed that the bacterial community structure differed between REGY, GY, and WGY. Furthermore, taxonomic groups did not present differences regarding gender in these three stages. The rumen microbiota was enriched with functional potentials that were related to ABC transporters, the two-component system, Aminoacyl-tRNA biosynthesis, and metabolism of Purine, Pyrimidine, Starch and sucrose metabolism. Significant differences were found in the composition, diversity, and function of yak ruminal microorganisms during different forage growth stages. This indicates that microbial changes in the rumen depend on changes in the forage nutritional composition. These findings provide evidence on the rumen microbial diversity of yaks in the QTP. C1 [Ma, Li; Xu, Shixiao; Liu, Hongjin; Xu, Tianwei; Hu, Linyong; Zhao, Na; Han, Xueping; Zhang, Xiaoling] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Qinghai, Peoples R China. [Ma, Li; Liu, Hongjin; Han, Xueping; Zhang, Xiaoling] Univ Chinese Acad Sci, Beijing, Peoples R China. [Ma, Li] Qinghai Grassland Stn, Xining, Qinghai, Peoples R China. RP Xu, SX (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Qinghai, Peoples R China. EM sxxu@nwipb.cas.cn TC 21 Z9 24 PD SEP 19 PY 2019 VL 7 AR e7645 DI 10.7717/peerj.7645 UT WOS:000486566300006 DA 2023-03-23 ER PT J AU Lin, ZJ Gao, ZY Niu, FJ Luo, J Yin, GA Liu, MH Fan, XW AF Lin, Zhanju Gao, Zeyong Niu, Fujun Luo, Jing Yin, Guoan Liu, Minghao Fan, Xingwen TI High spatial density ground thermal measurements in a warming permafrost region, Beiluhe Basin, Qinghai-Tibet Plateau SO GEOMORPHOLOGY DT Article AB Air, ground surface, and permafrost surface temperatures are important components of the permafrost thermal regime. However, ground temperatures from one or two boreholes are commonly considered representative of site conditions in permafrost studies despite significant variations in local surface conditions. This makes the evaluation of site-scale temperature variations important for improving the accuracy of permafrost modelling efforts. In this study we analyzed the variability in near-surface ground temperatures in a warming permafrost region using high spatial density borehole measurements to capture variations in surface conditions. Ground temperatures were collected from 72 boreholes drilled to 5 m depth at 8 sites in Beiluhe Basin, Qinghai-Tibet Plateau. Six sites straddled an alpine meadow ecotone between well- and sparsely-vegetated ground, and two sites were located on slopes with opposing aspects. Air temperatures at the 8 sites were similar with annual mean values ranging from -2.6 to -3.0 degrees C in 2016-18. In contrast, annual mean surface temperatures exhibited greater variation between sites, so that surface offsets were also variable. Ground surface temperatures were highest at a sloping sunny site, and lowest at a north-facing shady site. The results indicated that surface temperatures were strongly controlled by slope aspect. In contrast, the expected effect of vegetation cover shading was not distinguishable because of variations in soil moisture content between sites. Deeper temperatures at the permafrost surface and at 5 m depth exhibited a similar trend among sites except in an unusual warm transitional area where eolian erosion disturbed the surface vegetation cover. The detailed ground temperature records characterizing within- and between-site variations could be used in future to support the calibration and validation of numerical models of permafrost distribution. (C) 2019 Elsevier B.V. All rights reserved. C1 [Lin, Zhanju; Gao, Zeyong; Niu, Fujun; Luo, Jing; Yin, Guoan; Liu, Minghao; Fan, Xingwen] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Gansu, Peoples R China. RP Lin, ZJ (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Gansu, Peoples R China. EM zhanjulin@lzb.ac.cn TC 15 Z9 16 PD SEP 1 PY 2019 VL 340 BP 1 EP 14 DI 10.1016/j.geomorph.2019.04.032 UT WOS:000476964400001 DA 2023-03-23 ER PT J AU Qi, XZ Jia, JH Liu, HY Lin, ZS AF Qi, Xiangzhen Jia, Junhe Liu, Huiyu Lin, Zhenshan TI Relative importance of climate change and human activities for vegetation changes on China's silk road economic belt over multiple timescales SO CATENA DT Article AB Ecological issues of China's Silk Road Economic Belt are receiving increasing attention. It is necessary to monitor vegetation changes in the Belt and explore their relationship with climate changes and human activities to ensure sustainable regional socioeconomic development. However, there is no adequate understanding of the relative importance of climate changes and human activities on vegetation over multiple timescales. In this study, ensemble empirical mode decomposition (EEMD) and residual trends (RESTREND) methods were used to establish the relative importance over multiple timescales. (1) The dominant timescales of vegetation changes have obvious spatial heterogeneity, which was affected by vegetation types and elevation. Grassland in high altitude areas, needleleaf forest, and shrubland were characterized by 3-year oscillations. Low-altitude areas mainly covered by cropland were characterized by long-term trends. (2) Climate types mainly affected the relationship between vegetation and climate changes at short timescales, while vegetation types, elevation, landforms affected the relationship over each timescale. Over the 3-year timescale, temperature and precipitation had a negative and a positive relationship respectively with vegetation changes in semi-arid and arid regions, but a positive relationship and a negative relationship respectively in semi-humid and humid regions. As the timescale widened, temperature had a positive relationship in all areas, except for needleleaf forest, and precipitation had a positive relationship except in high-latitude areas dominated by alpine meadow and in karst areas. (3) Vegetation changes were dominated by human activities at 3- and 6-year timescales but by climate changes in the long-term trend. However, when considering the total effects of these three timescales, climate changes dominated the overall changes of vegetation, while human activities also played an important role in vegetation reduction and insignificant changes. Vegetation changes were influenced by cross-scale climate changes. This study showed that multiple timescale analysis could deepen our understanding of the roles of climate and human activities on vegetation changes. C1 [Qi, Xiangzhen; Jia, Junhe; Liu, Huiyu; Lin, Zhenshan] Nanjing Normal Univ, State Key Lab Cultivat Base Geog Environm Evolut, Nanjing 210023, Jiangsu, Peoples R China. [Qi, Xiangzhen; Jia, Junhe; Liu, Huiyu; Lin, Zhenshan] Nanjing Normal Univ, Minist Educ, Key Lab Virtual Geog Environm, Nanjing 210023, Jiangsu, Peoples R China. [Qi, Xiangzhen; Jia, Junhe; Liu, Huiyu; Lin, Zhenshan] Nanjing Normal Univ, Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Jiangsu, Peoples R China. [Qi, Xiangzhen; Jia, Junhe; Liu, Huiyu; Lin, Zhenshan] Nanjing Normal Univ, Coll Geog Sci, Nanjing 210023, Jiangsu, Peoples R China. RP Liu, HY (通讯作者)，Nanjing Normal Univ, State Key Lab Cultivat Base Geog Environm Evolut, Nanjing 210023, Jiangsu, Peoples R China. EM liuhuiyu@njnu.edu.cn TC 65 Z9 73 PD SEP PY 2019 VL 180 BP 224 EP 237 DI 10.1016/j.catena.2019.04.027 UT WOS:000472244900021 DA 2023-03-23 ER PT J AU Hu, L Zi, HB Wu, PF Wang, Y Lerdau, M Wu, XW Wang, CT AF Hu, Lei Zi, Hongbiao Wu, Pengfei Wang, Yong Lerdau, Manuel Wu, Xinwei Wang, Changting TI Soil bacterial communities in grasslands revegetated using Elymus nutans are largely influenced by soil pH and total phosphorus across restoration time SO LAND DEGRADATION & DEVELOPMENT DT Article AB Soil microbial communities have been considered indicators of soil quality and fertility changes in restored ecosystems. Little is known, however, about how these communities change over time after restoration in terms of activity, structure, and diversity. We evaluated the soil bacterial communities of 4-, 8-, and 12-year-old Elymus nutans revegetated grasslands located in the Qinghai-Tibetan Plateau. Soil bacterial diversity and composition significantly changed in the 8- and 12-year-old grasslands compared with the 4-year-old grassland. Surprisingly, soil bacterial communities transitioned from Proteobacteria- and Acidobacteria-dominant communities in the 4-year-old grassland to Cyanobacteria-dominant communities in the 8- and 12-year-old grasslands. Furthermore, the phylum of Cyanobacteria accounted for a high percentage of bacterial community (>48%) in the 8- and 12-year-old grasslands. Network analyses showed that most of the interactions were identified as positive among bacterial species, but Cyanobacteria were often negatively associated with other species. In addition, there was a slight increase in P acquisition enzymes (acid phosphatase activity) and a decline in N acquisition enzymes (soil urease and nitratase activities) with the increasing dominance of Cyanobacteria. Additionally, soil pH and total phosphorus had positive relationships with soil bacterial composition and diversity, whereas soil bacterial diversity and P acquisition enzymes were negatively related to soil bacterial composition. Overall, our results indicated that significant changes in soil bacterial communities might occur in response to the cultivation period of cultivated grassland and highlighted the importance of soil pH, TP, and P acquisition enzymes in microbe-mediated ecological processes of cultivated grassland on the Qinghai-Tibetan Plateau. C1 [Hu, Lei; Wu, Xinwei] Nanjing Univ, Sch Life Sci, 163,Xianlin Rd, Nanjing 210000, Jiangsu, Peoples R China. [Hu, Lei; Zi, Hongbiao; Wu, Pengfei; Wang, Yong; Wang, Changting] Southwest Minzu Univ, Inst Qinghai Tibetan Plateau Res, 16 South Sect 4,Yihuan Rd, Chengdu 610041, Sichuan, Peoples R China. [Zi, Hongbiao] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China. [Lerdau, Manuel] Univ Virginia, Dept Environm Sci, Charlottesville, VA 22903 USA. [Lerdau, Manuel] Univ Virginia, Dept Biol, Charlottesville, VA 22903 USA. RP Wu, XW (通讯作者)，Nanjing Univ, Sch Life Sci, 163,Xianlin Rd, Nanjing 210000, Jiangsu, Peoples R China.; Wang, CT (通讯作者)，Southwest Minzu Univ, Inst Qinghai Tibetan Plateau Res, 16 South Sect 4,Yihuan Rd, Chengdu 610041, Sichuan, Peoples R China. EM xinwei_8008@126.com; wangct@swun.edu.cn TC 10 Z9 12 PD DEC PY 2019 VL 30 IS 18 BP 2243 EP 2256 DI 10.1002/ldr.3414 EA AUG 2019 UT WOS:000482839800001 DA 2023-03-23 ER PT J AU Shen, H Dong, SK Li, S Xiao, JN Han, YH Yang, MY Zhang, J Gao, XX Xu, YD Li, Y Zhi, YL Liu, SL Dong, QM Zhou, HK Yeomans, JC AF Shen, Hao Dong, Shikui Li, Shuai Xiao, Jiannan Han, Yuhui Yang, Mingyue Zhang, Jing Gao, Xiaoxia Xu, Yudan Li, Yu Zhi, Yangliu Liu, Shiliang Dong, Quanming Zhou, Huakun Yeomans, Jane C. TI Effects of simulated N deposition on photosynthesis and productivity of key plants from different functional groups of alpine meadow on Qinghai-Tibetan plateau SO ENVIRONMENTAL POLLUTION DT Article AB Nitrogen (N) deposition may alter physiological process of plants in grassland ecosystem. However, little is known about the response mechanism of individual plants in alpine regions to N deposition. We conducted a field experiment, and three treatments including 0 kg Nha(-l) year(-1) (CK), 8 kgNha(-l) year(-1) (Low N), and 72 kg N ha(-1) year(-1) (High N) were established to simulate N deposition in alpine meadow of Qinghai-Tibetan plateau. Our objectives were to determine the influence of N deposition on photosynthesis of different functional types of herbage species in alpine meadow, and finally characterize the links of plant productivity and photosynthesis with soil nutrients. The results showed that responses of alpine plants were species-specific under N deposition. Compared with grass species Agropyron cristatum and forb species Thalictrum aquilegifolium, the sedge species Carex melanantha was much more sensitive to N deposition; a lower N load (8 kgNha(-1)year(-1)) can cause a negative effect on its photosynthesis and productivity. Additionally, N deposition can promote plant N uptake and significantly decreased the C (carbon)/N (nitrogen) ratio. Compared with CK and low N deposition, high N deposition inhibited the photosynthesis and growth of the forb species Thalictrum aquilegifolium and sedge species Carex melanantha. In all three functional types of herbage species, the grass species A. cristatum tended to show a much higher photosynthetic capacity and better growth potential; thus, suggesting that grass species A. cristatum will be a more adaptative alpine plants under N deposition. Our findings suggested that plant photosynthetic responses to N deposition were species-specific, low N deposition was not beneficial for all the herbage species, and N deposition may change plant composition by the differential photosynthetic responses among species in alpine grassland. Plant composition shift to grass-dorminant in alpine regions might be attributed to a much higher photosynthetic potential and N use efficiency of grass species. (C) 2019 Elsevier Ltd. All rights reserved. C1 [Shen, Hao; Dong, Shikui; Li, Shuai; Xiao, Jiannan; Han, Yuhui; Yang, Mingyue; Zhang, Jing; Gao, Xiaoxia; Xu, Yudan; Li, Yu; Zhi, Yangliu; Liu, Shiliang] Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. [Dong, Quanming] Qinghai Univ, Qinghai Acad Anim Husb & Vet Sci, Xining 810003, Qinghai, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Qinghai Prov, Xining 810008, Qinghai, Peoples R China. [Yeomans, Jane C.] Earth Univ, Res Dept, San Jose, Costa Rica. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. EM dsk03037@bnu.edu.cn TC 18 Z9 21 PD AUG PY 2019 VL 251 BP 731 EP 737 DI 10.1016/j.envpol.2019.05.045 UT WOS:000474329700080 DA 2023-03-23 ER PT J AU Dai, LC Guo, XW Ke, X Zhang, FW Li, YK Peng, CJ Shu, K Li, Q Lin, L Cao, GM Du, YG AF Dai, Licong Guo, Xiaowei Ke, Xun Zhang, Fawei Li, Yikang Peng, Cuoji Shu, Kai Li, Qian Lin, Li Cao, Guangmin Du, Yangong TI Moderate grazing promotes the root biomass in Kobresia meadow on the northern Qinghai-Tibet Plateau SO ECOLOGY AND EVOLUTION DT Article AB Grazing is an important modulator of both plant productivity and biodiversity in grassland community, yet how to determine a suitable grazing intensity in alpine grassland is still controversy. Here, we explore the effects of different grazing intensities on plant biomass and species composition, both at community level and functional group level, and examines the productivity-species richness relationship under four grazing patterns: no grazing (CK), light grazing (LG), moderate grazing, (MG) and heavy grazing (HG), attempt to determine a suitable grazing intensity in alpine grassland. The results were as follows. The total aboveground biomass (AGB) reduced with increasing grazing intensity, and the response of plant functional groups was different. AGB of both sedges and legumes increased from MG to HG, while the AGB of forbs reduced sharply and the grass AGB remained steady. There was a significant positive relationship between productivity and species richness both at community level and functional group level. In contrast, the belowground biomass (BGB) showed a unimodal relationship from CK to HG, peaking in MG (8,297.72 +/- 621.29 g/m(2)). Interestingly, the grassland community tends to allocate more root biomass to the upper soil layer under increasing grazing intensities. Our results suggesting that moderate levels of disturbance may be the optimal grassland management strategy for alpine meadow in terms of root production. C1 [Dai, Licong; Guo, Xiaowei; Ke, Xun; Zhang, Fawei; Li, Yikang; Peng, Cuoji; Shu, Kai; Li, Qian; Lin, Li; Cao, Guangmin; Du, Yangong] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Bot, Xining, Qinghai, Peoples R China. [Dai, Licong; Ke, Xun; Peng, Cuoji] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhang, Fawei] Luoyang Normal Univ, Coll Life Sci, Luoyang, Peoples R China. RP Du, YG (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Bot, Xining, Qinghai, Peoples R China. EM ygdu@nwipb.cas.cn TC 19 Z9 22 PD AUG PY 2019 VL 9 IS 16 BP 9395 EP 9406 DI 10.1002/ece3.5494 EA JUL 2019 UT WOS:000479452000001 DA 2023-03-23 ER PT J AU Liu, L Zeng, K Wu, N Zhang, XQ Sun, FD Chen, DM Gao, WC Zhou, JQ Zhao, JX You, CM Sun, G AF Liu, Lin Zeng, Kai Wu, Ning Zhang, Xinquan Sun, Feida Chen, Dongming Gao, Wuchao Zhou, Jiqiong Zhao, Jingxue You, Chengming Sun, Geng TI Variation in physicochemical and biochemical soil properties among different plant species treatments early in the restoration of a desertified alpine meadow SO LAND DEGRADATION & DEVELOPMENT DT Article AB Soil nutrients, enzyme activities, and microbial biomass have important significance for biogeochemical cycles and are affected by vegetation restoration in degradation ecosystems. To explore the effects of replanting different plant species on soil restoration in a desertified alpine meadow on the eastern Tibetan Plateau and to optimize the restoration process with locally appropriate plant species, the soil physicochemical and biochemical properties were measured beneath the plant species Rhodiola kirilowii, Salix cupularis, and Kengyilia rigidula over two periods of vegetative growth (2 years and 5 years). The results showed that all the soil properties significantly improved over the recovery periods (p < .001) and the plant species significantly affected the patterns of soil bulk density, available resources, and biochemical properties (p < .05). However, R. kirilowii improved soil properties most significantly among the three plant species as the recovery time elapsed, and these improvements were strongly related to the greatest fresh vegetation biomass and coverage. Furthermore, R. kirilowii enhanced microbial biomass phosphorus even more, which is an important available phosphorus stock in the soil, and more effectively promoted the development of soil fungi than the two other species. Therefore, we suggest that R. kirilowii is the preferred species of the three to expedite the recovery of desertified alpine soil, and that the appropriate addition of P fertilizer and propelling the development of specific fungi groups in the soil are key to soil restoration in the desertified alpine meadow. C1 [Liu, Lin; Zeng, Kai; Zhang, Xinquan; Sun, Feida; Gao, Wuchao; Zhou, Jiqiong; Zhao, Jingxue] Sichuan Agr Univ, Coll Anim Sci & Technol, 211 Huimin Rd, Chengdu 611130, Sichuan, Peoples R China. [Zeng, Kai] Hunan Tianquan Ecol Prataculture Engn Co Ltd, Tech Dept, Changsha 410000, Hunan, Peoples R China. [Wu, Ning; Sun, Geng] Chinese Acad Sci, CAS Key Lab Mt Ecol Restorat & Bioresource Utiliz, Chengdu Inst Biol, Chengdu 610041, Sichuan, Peoples R China. [Wu, Ning; Sun, Geng] Chinese Acad Sci, Ecol Restorat & Biodivers Conservat Key Lab Sichu, Chengdu Inst Biol, Chengdu 610041, Sichuan, Peoples R China. [Chen, Dongming] Inst Anim Husb Sci, Sichuan Ganzi Tibetan Autonomous Prefecture, Kangding 626000, Sichuan, Peoples R China. [You, Chengming] Sichuan Agr Univ, Long Term Res Stn Alpine Forest Ecosyst, Prov Key Lab Ecol Forestry Engn, Inst Ecol & Forestry, Chengdu 611130, Sichuan, Peoples R China. RP Liu, L (通讯作者)，Sichuan Agr Univ, Coll Anim Sci & Technol, 211 Huimin Rd, Chengdu 611130, Sichuan, Peoples R China. EM liulinsky@126.com TC 7 Z9 9 PD OCT PY 2019 VL 30 IS 16 BP 1889 EP 1903 DI 10.1002/ldr.3376 EA JUL 2019 UT WOS:000477137400001 DA 2023-03-23 ER PT J AU Yao, ZS Ma, L Zhang, H Zheng, XH Wang, K Zhu, B Wang, R Wang, YQ Zhang, W Liu, CY Butterbach-Bahl, K AF Yao, Zhisheng Ma, Lei Zhang, Han Zheng, Xunhua Wang, Kai Zhu, Bo Wang, Rui Wang, Yanqiang Zhang, Wei Liu, Chunyan Butterbach-Bahl, Klaus TI Characteristics of annual greenhouse gas flux and NO release from alpine meadow and forest on the eastern Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB The importance of the world's largest plateau (i.e., the Tibetan Plateau) as a source/sink for atmospheric greenhouse gases (GHGs) still remains uncertain as field observations covering entire years and contrasting ecosystems are scarce. Here we report on year-round measurements of methane (CH4), nitrous oxide (N2O) and nitric oxide (NO) fluxes from two representative ecosystems (cattle-grazed meadow and natural forest, > 3300 m a.s.l) on the eastern Tibetan Plateau. In our study, the alpine soils generally functioned as sinks for atmospheric CH4. The pronounced seasonality of CH4 uptake, with higher uptake in the growing season and lower uptake in the non-growing season, was mainly regulated by the combined changes in soil moisture and temperature. Soil CH4 uptake was lower at the meadow site due to high soil moisture and grazing-induced soil compaction reducing gas diffusivity and hampering CH4 uptake. For the alpine meadow pulses of N-oxide fluxes were observed during the freeze-thaw period, while freeze-thaw related pulses did not occur at the forest site, where the seasonality of N-oxide fluxes was primarily regulated by changes in soil temperature (Q(10) = 3.0). Annual cumulative fluxes for the meadow and forest ecosystems ranged between -1.15 and -2.24 kg CH4-C ha(-1) yr(-1), 0.13-0.65 kg N2O-N ha(-1) yr(-1) and 0.022-0.047 kg NO-N ha(-1) yr(-1). Non-growing season fluxes contributed 34-45% and 21-51% to the annual budgets of CH4 and N-oxides, respectively. Multiple regression analyses showed that soil N-oxide fluxes were significantly positively correlated to concentrations of soil dissolved organic C (DOC) and inorganic N, with DOC and inorganic N concentrations being higher at the forest site. Our study also shows that alpine forest is a stronger source for non-CO2 GHGs relative to alpine meadow (higher by 195 kg CO2-eq ha(-1) yr(-1)). This difference in GHG fluxes significantly offsets the net climate benefits due to increased C-sequestration associated with afforestation/reforestation. C1 [Yao, Zhisheng; Ma, Lei; Zhang, Han; Zheng, Xunhua; Wang, Kai; Wang, Rui; Zhang, Wei; Liu, Chunyan; Butterbach-Bahl, Klaus] Chinese Acad Sci, Inst Atmospher Phys, State Key Lab Atmospher Boundary Layer Phys & Atm, Beijing 100029, Peoples R China. [Zheng, Xunhua] Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China. [Zhu, Bo; Wang, Yanqiang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolvement & Regulat, Chengdu 610041, Sichuan, Peoples R China. [Butterbach-Bahl, Klaus] Karlsruhe Inst Technol, Atmospher Environm Res, Inst Meteorol & Climate Res, D-82467 Garmisch Partenkirchen, Germany. RP Yao, ZS (通讯作者)，Chinese Acad Sci, Inst Atmospher Phys, State Key Lab Atmospher Boundary Layer Phys & Atm, Beijing 100029, Peoples R China. EM zhishengyao@mail.iap.ac.cn TC 14 Z9 15 PD JUL 15 PY 2019 VL 272 BP 166 EP 175 DI 10.1016/j.agrformet.2019.04.007 UT WOS:000469158400015 DA 2023-03-23 ER PT J AU Bei, XY Yao, YJ Zhang, LL Xu, TR Jia, K Zhang, XT Shang, K Xu, J Chen, XW AF Bei, Xiangyi Yao, Yunjun Zhang, Lilin Xu, Tongren Jia, Kun Zhang, Xiaotong Shang, Ke Xu, Jia Chen, Xiaowei TI Long-Term Spatiotemporal Dynamics of Terrestrial Biophysical Variables in the Three-River Headwaters Region of China from Satellite and Meteorological Datasets SO REMOTE SENSING DT Article AB Terrestrial biophysical variables play an essential role in quantifying the amount of energy budget, water cycle, and carbon sink over the Three-River Headwaters Region of China (TRHR). However, direct field observations are missing in this region, and few studies have focused on the long-term spatiotemporal variations of terrestrial biophysical variables. In this study, we evaluated the spatiotemporal dynamics of biophysical variables including meteorological variables, vegetation, and evapotranspiration (ET) over the TRHR, and analyzed the response of vegetation and ET to climate change in the period from 1982 to 2015. The main input gridded datasets included meteorological reanalysis data, a satellite-based vegetation index dataset, and the ET product developed by a process-based Priestley-Taylor algorithm. Our results illustrate that: (1) The air temperature and precipitation over the TRHR increased by 0.597 degrees C and 41.1 mm per decade, respectively, while the relative humidity and surface downward shortwave radiation declined at a rate of 0.9% and 1.8 W/m(2) per decade during the period 1982-2015, respectively. We also found that a dryer warming' tendency and a wetter warming' tendency existed in different areas of the TRHR. (2) Due to the predominant wetter warming' tendency characterized by the increasing temperature and precipitation, more than 56.8% of areas in the TRHR presented a significant increment in vegetation (0.0051/decade, p < 0.05), particularly in the northern and western meadow areas. When energy was the limiting factor for vegetation growth, temperature was a considerably more important driving factor than precipitation. (3) The annual ET of the TRHR increased by 3.34 mm/decade (p < 0.05) with an annual mean of 230.23 mm/year. More importantly, our analysis noted that ET was governed by terrestrial water supply, e.g., soil moisture and precipitation in the arid region of the western TRHR. By contrast, atmospheric evaporative demand derived by temperature and relative humidity was the primary controlling factor over the humid region of the southeastern TRHR. It was noted that land management activities, e.g., irrigation, also had a nonnegligible impact on the temporal and spatial variation of ET. C1 [Bei, Xiangyi; Yao, Yunjun; Jia, Kun; Zhang, Xiaotong; Shang, Ke; Xu, Jia; Chen, Xiaowei] Beijing Normal Univ, State Key Lab Remote Sensing Sci, Fac Geog Sci, Beijing 100875, Peoples R China. [Zhang, Lilin] Univ Twente, Fac Geoinformat & Earth Observat ITC, NL-7500 AE Enschede, Netherlands. [Xu, Tongren] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Fac Geog Sci, Beijing 100875, Peoples R China. RP Yao, YJ (通讯作者)，Beijing Normal Univ, State Key Lab Remote Sensing Sci, Fac Geog Sci, Beijing 100875, Peoples R China. EM yaoyunjun@bnu.edu.cn TC 6 Z9 7 PD JUL 2 PY 2019 VL 11 IS 14 AR 1633 DI 10.3390/rs11141633 UT WOS:000480527800003 DA 2023-03-23 ER PT J AU Du, YG Zhou, G Guo, XW Cao, GM AF Du, Yangong Zhou, Geng Guo, Xiaowei Cao, Guangmin TI Spatial distribution of grassland soil organic carbon and potential carbon storage on the Qinghai Plateau SO GRASSLAND SCIENCE DT Article AB Mapping the soil organic carbon (SOC) properties of terrestrial ecosystems is necessary to mitigate carbon flux. Here, we quantified grassland SOC contents and densities to evaluate the potential for increased storage through recovery on the Qinghai Plateau. The SOC contents of 41 paired soil profiles from areas of nondegraded and degraded grasslands were analyzed in 2012 using a dry oxidation method. The average SOC contents of nondegraded and degraded grasslands were 3.4 +/- 0.3% and 2.4 +/- 0.4% (p < 0.05). The SOC density changes varied from -5.5 to 13.2 kg/m(2) in a future grassland restoration scenario. The predicted main regions of potential increasing SOC density were located in the counties Zhiduo, Qilian, Menyuan, Maduo, Gande and Zeku. Moreover, the potential SOC stock would increase by 0.83 pg due to grassland restoration, suggesting a key role of alpine grassland as carbon sink on the Qinghai Plateau. C1 [Du, Yangong; Guo, Xiaowei; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining, Qinghai, Peoples R China. [Zhou, Geng] Bur Agr Weihai, Weihai, Peoples R China. RP Du, YG (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining, Qinghai, Peoples R China. EM ygdu@nwipb.cas.cn TC 11 Z9 11 PD JUL PY 2019 VL 65 IS 3 BP 141 EP 146 DI 10.1111/grs.12229 UT WOS:000473627500001 DA 2023-03-23 ER PT J AU Gao, XX Dong, SK Xu, YD Wu, SN Wu, XH Zhang, X Zhi, YL Li, S Liu, SL Li, Y Shang, ZH Dong, QM Zhou, HK Stufkens, P AF Gao, Xiaoxia Dong, Shikui Xu, Yudan Wu, Shengnan Wu, Xiaohui Zhang, Xi Zhi, Yangliu Li, Shuai Liu, Shiliang Li, Yu Shang, Zhanhuan Dong, Quanmin Zhou, Huakun Stufkens, Paul TI Resilience of revegetated grassland for restoring severely degraded alpine meadows is driven by plant and soil quality along recovery time: A case study from the Three-river Headwater Area of Qinghai-Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Resilience is crucial to promote the ecosystem sustainability and maintain ecosystem functions and services. Clarifying the variation regularity of the resilience can provide a theory foundation for the restoration and management of degraded ecosystems. Grassland cultivation has been largely used to restore extensively distributed "Black Beach", the severely degraded alpine meadow on the Qinghai-Tibetan Plateau (QTP). However, few researchers have documented the resilience of the revegetated grasslands along the succession gradients. In this study, we surveyed the revegetated grasslands on the QTP at different restoration times: 4-year, 6-year, 9-year, 12-year, 13-year, 14-year, 16-year, 18-year by using chronosequence approach to identify the resilience of the revegetated grasslands from the perspectives of plant and soil quality. We treated "Black Beach" as the baseline for restoration, and non-degraded healthy alpine meadow as the target for the restoration. We used the MDS method to identify the appropriate indicators and created an integrated assessment system that quantified the resilience of plant, soil, plant-soil system of the revegetated grasslands at different recovery years. The results showed that the non-linear resilience of revegetated grasslands were identified for the plant, soil and plant-soil systems along the temporal gradients. The plant resilience of the revegetated grasslands peaked at the 12th recovery year. The soil of the revegetated grasslands was superior to severely degraded grasslands after 13 years of revegetation. Asynchrony existed between the resilience of soil and that of the plant along the temporal gradients. The plant-soil system resilience of the revegetated grasslands peaked at the 16th recovery year. From the perspectives of plant, soil, plant-soil system, the recovery time of severely degraded grassland should be at least 16-18 years to reach a relative stable state. Revegetated grassland can be used as an effective restoration approach to improve the quality and resilience of plant and soil in the severely degraded alpine meadow on the QTP. C1 [Gao, Xiaoxia; Dong, Shikui; Xu, Yudan; Wu, Shengnan; Wu, Xiaohui; Zhang, Xi; Zhi, Yangliu; Li, Shuai; Liu, Shiliang; Li, Yu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Fernow Hall, Ithaca, NY 14853 USA. [Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, Sate Key Lab Grassland Agoecosyst, Lanzhou 730000, Gansu, Peoples R China. [Dong, Quanmin] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Xining 810016, Qinghai, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining 810008, Qinghai, Peoples R China. [Stufkens, Paul] Zamorano Univ, Francisco Morazan 93, Valle Del Yeguare, Honduras. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 44 Z9 47 PD JUL 1 PY 2019 VL 279 BP 169 EP 177 DI 10.1016/j.agee.2019.01.010 UT WOS:000482173600019 DA 2023-03-23 ER PT J AU Li, CM Wang, YM Fang, T Zhou, XK Cui, P AF Li, Chunmei Wang, Yuming Fang, Tian Zhou, Xinke Cui, Peng TI A neural network decision expert system for alpine meadow degradation in the Sanjiangyuan region SO CLUSTER COMPUTING-THE JOURNAL OF NETWORKS SOFTWARE TOOLS AND APPLICATIONS DT Article AB This paper introduced detailed the design of intelligent system for decision-making. Firstly, the overall design of grassland degradation decision-making system of Sanjiangyuan based on neural network is carried out, including man-machine interface module, knowledge base module, neural network module and inference engine module. Secondly, the specific functions of each module are introduced. Finally, the design of neural network was introduced detailed, the entire BP neural network consists of three layers of structure. There are five nodes in the input layer, five nodes in the output layer, and six nodes in the hidden layer. C1 [Li, Chunmei; Wang, Yuming; Fang, Tian; Zhou, Xinke; Cui, Peng] Qinghai Univ, Dept Comp Technol & Applicat, Xining, Qinghai, Peoples R China. RP Li, CM (通讯作者)，Qinghai Univ, Dept Comp Technol & Applicat, Xining, Qinghai, Peoples R China. EM li_chm0422@sina.com TC 2 Z9 2 PD JUL PY 2019 VL 22 SU 4 BP S8193 EP S8198 DI 10.1007/s10586-018-1698-x UT WOS:000502007000050 DA 2023-03-23 ER PT J AU Li, JJ Yang, C Liu, XL Shao, XQ AF Li, Jingjing Yang, Chao Liu, Xiaoli Shao, Xinqing TI Inconsistent stoichiometry response of grasses and forbs to nitrogen and water additions in an alpine meadow of the Qinghai-Tibet Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB The increase in atmospheric nitrogen (N) deposition and precipitation is obvious in the eastern Qinghai-Tibet Plateau. The response of different plant functional groups to increased N deposition and precipitation and the mechanism of N and phosphorus (P) stoichiometry are not yet clear. We examined the effects of the addition of N and water on plant diversity, community productivity and plant N:P stoichiometry of functional groups in an alpine meadow of the Qinghai-Tibet Plateau in China. Our results indicate that N and water additions significantly increased the total above-ground productivity and biomass of grasses in both years but decreased the biomass of forbs in 2018. In addition, plant diversity decreased with a high level of N addition, and the interactions of N and water had a weakening effect on the decline of plant diversity. Plant diversity was negatively correlated with the biomass of grasses. Our results demonstrate that the biomass of grasses showed a negative quadratic relationship with the N:P ratio of grasses, suggesting that addition of N and water shifted the grasses from N-limited to P-limited. The biomass of forbs showed significant positive correlations with the N:P ratio of forbs, implying the forbs still remained N limited. Overall, our study suggests that the response of grasses and forbs to water and N additions is inconsistent from the perspective of plant N:P stoichiometry. C1 [Li, Jingjing; Yang, Chao; Liu, Xiaoli; Shao, Xinqing] China Agr Univ, Coll Anim Sci & Technol, 2 Yuan Ming Yuan West Rd, Beijing 100193, Peoples R China. RP Shao, XQ (通讯作者)，China Agr Univ, Coll Anim Sci & Technol, 2 Yuan Ming Yuan West Rd, Beijing 100193, Peoples R China. EM shaoxinqing@163.com TC 16 Z9 19 PD JUL 1 PY 2019 VL 279 BP 178 EP 186 DI 10.1016/j.agee.2018.12.016 UT WOS:000482173600020 DA 2023-03-23 ER PT J AU Xu, YD Dong, SK Gao, XX Yang, MY Li, S Shen, H Xiao, JN Han, YH Zhang, J Li, Y Zhi, YL Yang, YF Liu, SL Dong, QM Zhou, HK Stufkens, P AF Xu, Yudan Dong, Shikui Gao, Xiaoxia Yang, Mingyue Li, Shuai Shen, Hao Xiao, Jiannan Han, Yuhui Zhang, Jing Li, Yu Zhi, Yangliu Yang, Yunfeng Liu, Shiliang Dong, Quanming Zhou, Huakun Stufkens, Paul TI Trade-offs and cost-benefit of ecosystem services of revegetated degraded alpine meadows over time on the Qinghai-Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB A great number of ecological conservation and restoration projects have been implemented to prevent the deterioration of alpine grasslands on the Qinghai-Tibetan Plateau. However, few researches have documented the effects of ecological projects on the improvement of ecosystem services of alpine grasslands based on field investigations. In this study, 24 plots of alpine meadow along different succession times were investigated to estimate the impacts of ecological restoration on four key ecosystem services (i.e., soil organic carbon sequestration (SOCS), soil total nitrogen sequestration (STNS), biodiversity, and aboveground biomass) in the Glog Tibetan Autonomous Prefecture of Qinghai Province, China. The results showed that STNS and biodiversity of degraded alpine meadows were significantly improved through restoration actions, while SOCS and aboveground biomass didn't change. The relationships of above- and belowground ecosystem services changed over restoration time. Trade-offs between aboveground biomass and biodiversity, between aboveground biomass and SOCS at stage III were significantly improved, in contrast to those at stage I. Trade-off between STNS and biodiversity at stage II was significantly increased, in contrast to those at stage I. Economic profit of ecological restoration was insignificantly changed along restoration time. Our results suggested that human-induced restoration was a feasible approach to improve the ecological and economical values of "Black Beach" on the Qinghai-Tibetan Plateau, and further restoration actions and long-term research are required to enhance the ecosystem services of revegetated degraded meadow. C1 [Xu, Yudan; Dong, Shikui; Gao, Xiaoxia; Yang, Mingyue; Li, Shuai; Shen, Hao; Xiao, Jiannan; Han, Yuhui; Zhang, Jing; Li, Yu; Zhi, Yangliu; Liu, Shiliang] Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. [Yang, Yunfeng] Tsinghua Univ, Sch Environm, Beijing 100084, Peoples R China. [Dong, Quanming] Qinghai Univ, Qinghai Acad Anim Husb & Vet Sci, Xining 810003, Qinghai, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Are Qinghai Prov, Xining 810008, Qinghai, Peoples R China. [Stufkens, Paul] Zamorano Univ, Tegucigalpa, Honduras. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. EM dsk03037@bnu.edu.cn TC 24 Z9 24 PD JUL 1 PY 2019 VL 279 BP 130 EP 138 DI 10.1016/j.agee.2019.04.015 UT WOS:000482173600015 DA 2023-03-23 ER PT J AU Yuan, ZQ Jiang, XJ Liu, GJ Jin, HJ Chen, J Wu, QB AF Yuan, Zi-Qiang Jiang, Xiao-Jin Liu, Guo-Jun Jin, Hui-Jun Chen, Ji Wu, Qing-Bai TI Responses of soil organic carbon and nutrient stocks to human-induced grassland degradation in a Tibetan alpine meadow SO CATENA DT Article AB Alpine meadow degradation is a major environmental problem in the Qinghai-Tibetan Plateau of China. While it is expanding at a rapid pace, quantitative information on the effect of grassland degradation on soil properties remains largely unavailable. This study aimed to evaluate the effect of vegetation cover reduction on soil organic carbon (SOC) and nutrient stocks. A degraded alpine meadow with vegetation cover gradients of 90% +/- 6.6% to 70% +/- 8.3% and 45% +/- 8.7% was selected, and soil samples were collected at two soil depths (0-20 and 20-40 cm depths). The reduction in vegetation cover decreased soil sand, SOC, total nitrogen (N), available phosphorus (P), inorganic N, microbial biomass carbon and N, soil moisture, and the ratio of SOC to available P, but increased soil pH, bulk density, the ratio of SOC to total N, and clay and silt contents. The decline in vegetation cover from 90% to 45% significantly affected SOC, total N, total P, and available P stocks at 0-40 cm soil depths (p < 0.05, respectively), with losses as high as 3.89 kg m(-2) for SOC, 0.47 kg m(-2) for total N, and 1.05 g m(-2) for available P. These values corresponded to depletion rates at 28.7%, 39%, and 21%. The increases were as high as 39 g m(-2) for total P and corresponded to an increase rate of 15%. The structural stability index had a linear decrease trend with decreasing vegetation cover. The index was > 9% at the COV90 site and was close to 5% at the COV45 site for 0-20 cm soil depth. These results confirmed that vegetation cover reduction is a key factor that influences the soil nutrient stocks and structural stability of the alpine meadow. The losses in SOC and nutrients by vegetation cover reduction on the alpine meadow can have a remarkable influence on a large scale. Meanwhile, the alpine meadow may have huge carbon and N sequestration potentials duo to the potential increase of vegetation productivity in this area. C1 [Yuan, Zi-Qiang; Liu, Guo-Jun; Jin, Hui-Jun; Chen, Ji; Wu, Qing-Bai] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Gansu, Peoples R China. [Jiang, Xiao-Jin] Chinese Acad Sci, Key Lab Trop Forest Ecol, Xishuangbanna Trop Bot Garden, Menglun 666303, Yunnan, Peoples R China. [Liu, Guo-Jun; Chen, Ji] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Beiluhe Observat Stn Frozen Soil Environm & Engn, Lanzhou 730000, Gansu, Peoples R China. RP Yuan, ZQ (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Gansu, Peoples R China. EM yuanzq@lzb.ac.cn TC 22 Z9 27 PD JUL PY 2019 VL 178 BP 40 EP 48 DI 10.1016/j.catena.2019.03.001 UT WOS:000466999700005 DA 2023-03-23 ER PT J AU Zhang, FW Li, HQ Li, YK Guo, XW Dai, LC Lin, L Cao, GM Li, YN Zhou, HK AF Zhang, Fawei Li, Hongqin Li, Yikang Guo, Xiaowei Dai, Licong Lin, Li Cao, Guangmin Li, Yingnian Zhou, Huakun TI Strong seasonal connectivity between shallow groundwater and soil frost in a humid alpine meadow, northeastern Qinghai-Tibetan Plateau SO JOURNAL OF HYDROLOGY DT Article AB The freeze-thaw cycle in the active soil layer plays a crucial role in cold-region hydrological processes, yet the effect of vertical water migration caused by the soil frost on shallow groundwater remains poorly quantified. The shallow groundwater level (GWL), soil frost depth and main environmental controls were monitored in a humid alpine meadow on the northeastern Qinghai-Tibetan Plateau from 2012 to 2017. GWL fluctuated with two seasonal maxima and minima during soil frost-centric year from November to October. GWL declined remarkably from the strong peak (3.9 +/- 0.2 m, Mean +/- S.D.) in mid-January to the strong minimum (4.8 +/- 0.1 m) in mid-May, and then increased to the second peak (4.2 +/- 0.2 m) in late August. This seasonal variability in GWL was mainly attributed to the freeze-thaw processes of the lower layer soil frost from November to late June both at a similar to 45-day delay, respectively. The clear increasing GWL from mid-November to mid-January was probably related to the melted upper layer soil frost, which was detained in subsoil layers because of the high thermal isolating effect in topsoil Mattic Epipedon (dense organic-rich turf) and the associated negative subsoil profile temperature gradient from mid-May to late August. The seasonal N-type in GWL was thus hysteretically determined by the soil freeze-thaw processes and the related subsoil profile temperature gradient. Annually, GWL was significantly correlated with air temperature (R-2 = 0.88, P = 0.003, N = 6), suggesting the shallow groundwater recharges would be weakened under the warming scenario. Annual GWL was not directly connected with annual precipitation (P = 0.81), likely owing to the high water holding capacity of the topsoil Mattic Epipedon and the similarity between precipitation input and evapotranspiration loss. This critical buffering function of the topsoil Mattic Epipedon in vertical moisture movement should be taken into consideration when modeling regional water dynamics in humid alpine meadows. C1 [Zhang, Fawei; Li, Hongqin] Luoyang Normal Univ, Coll Life Sci, Luoyang 471934, Henan, Peoples R China. [Zhang, Fawei; Li, Hongqin; Li, Yikang; Guo, Xiaowei; Dai, Licong; Lin, Li; Cao, Guangmin; Li, Yingnian; Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Qinghai, Peoples R China. [Zhang, Fawei; Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining 810001, Qinghai, Peoples R China. RP Zhang, FW; Cao, GM (通讯作者)，23 Xinning St, Xining 810001, Qinghai, Peoples R China. EM mywing963@126.com; caogm@nwipb.cas.cn TC 17 Z9 19 PD JUL PY 2019 VL 574 BP 926 EP 935 DI 10.1016/j.jhydrol.2019.05.008 UT WOS:000476962800072 DA 2023-03-23 ER PT J AU Wei, WR Knops, JMH Zhang, WG AF Wei, Wanrong Knops, Johannes M. H. Zhang, Weiguo TI The impact of plateau pikas (Ochotona curzoniae) on alpine grassland vegetation and soil is not uniform within the home range of pika families SO PLANT ECOLOGY & DIVERSITY DT Article AB Background: Plateau pika (Ochotona curzoniae) is a small lagomorph mammal, common in alpine meadows. Previous studies show that pika activity is not uniform within a home range of a pika family. However, whether such small-scale differences in pika activities induce spatial patterns of soil and vegetation parameters is unclear. Aims: Our aim was to examine if the impact of pikas on the vegetation and soil was uniform within a pika family's home range. Methods: Vegetation and soil were sampled in eight individual pika family's home ranges and control areas. We divided each pika home range into three areas that differed in pika activity, the highest activity being in the central of the home range, declining further away from the central. Results: Vegetation cover, vegetation height, above-ground biomass the abundance of graminoids, root biomass, soil moisture, NO3-N, soil organic carbon, the soil pH,soil bulk density and NH4-N showed a clear pattern that correlated with pika activity levels. However, other soil nutrients showed no clear patterns. Conclusion: Because individual pika families do notuse their home ranges uniformly, their spatial pattern of activity intensity within a home range induce a spatial patchiness in boththe vegetation and the soil. C1 [Wei, Wanrong] China West Normal Univ, Coll Life Sci, Key Lab Southwest China Wildlife Resources Conser, Nanchong, Peoples R China. [Wei, Wanrong; Zhang, Weiguo] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. [Knops, Johannes M. H.] Univ Nebraska, Sch Biol Sci, Lincoln, NE USA. RP Wei, WR (通讯作者)，China West Normal Univ, Coll Life Sci, Key Lab Southwest China Wildlife Resources Conser, Nanchong, Peoples R China.; Wei, WR; Zhang, WG (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou, Peoples R China. EM weiwr07@lzu.edu.cn; weizhang12332@163.com TC 12 Z9 14 PD SEP 3 PY 2019 VL 12 IS 5 BP 417 EP 426 DI 10.1080/17550874.2019.1628113 EA JUN 2019 UT WOS:000472914800001 DA 2023-03-23 ER PT J AU Zhang, X Liu, X Zhang, LF Chen, ZG Zhao, L Li, Q Chen, DD Gu, S AF Zhang, Xiang Liu, Xiaoqin Zhang, Lifeng Chen, Zhiguang Zhao, Liang Li, Qi Chen, Dongdong Gu, Song TI Comparison of energy partitioning between artificial pasture and degraded meadow in three-river source region on the Qinghai-Tibetan Plateau: A case study SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB To reveal the differences in energy exchange between a degraded alpine meadow (DM) and an artificial pasture (AP, that was artificially planted with Elymus nutans on the ploughed degraded meadow), the energy partitioning and its biophysical controls were compared between the two study sites in the Three-River Source Region (TRSR) on the Qinghai-Tibetan Plateau. The mean maximum leaf area index (LAI) for AP and DM was 2.66 and 1.08 m(2) m(-2), respectively. The net radiation (R-n) sensible heat flux (H) latent heat flux (lambda E), and soil heat flux (G) showed similar seasonal changes for the two study sites; no obvious differences in energy partitioning were noted between AP and DM during the non-growing season. However, during the growing season, R-n of DM was about 5.4% higher than that of AP, although almost the same downward shortwave and longwave radiation was received at both sites. Moreover, the mean albedo (alpha) of DM was lower by 0.02 than that of AP, and the mean soil surface temperature of DM was 4.1 degrees C lower than that of AP. The partitioning of available energy into H and lambda E of DM differed markedly from those of AP, and the lambda E/R-n ratio of DM was 16.4% higher than that of AP, whereas the H/R-n ratio of the former was 20.9% lower than that of the latter during the growing season. The growing season (annual) mean Bowen ratio (beta) was 0.69 +/- 0.04 and 0.90 +/- 0.03 (2.38 +/- 0.09 and 2.93 +/- 0.12) at DM and AP, respectively, indicating that more available energy of DM was used for lambda E in comparison with that for AP. The difference in vegetation was considered to be the major factor leading to differences in the energy partitioning between the two sites. The results of the case study suggest that meadow degradation increases water loss through evapotranspiration and that enlarging the area of artificial pasture can increase the plant productivity and improve the water conservation capacity in this region. C1 [Zhang, Xiang; Liu, Xiaoqin; Zhang, Lifeng; Chen, Zhiguang; Gu, Song] Nankai Univ, Coll Life Sci, 94 Weijin Rd, Tianjin 300071, Peoples R China. [Zhao, Liang; Li, Qi; Chen, Dongdong] Chinese Acad Sci, Northwest Plateau Inst Biol, 23 Xining Rd, Xining 810008, Qinghai, Peoples R China. RP Gu, S (通讯作者)，Nankai Univ, Coll Life Sci, 94 Weijin Rd, Tianjin 300071, Peoples R China. EM songgu@nankai.edu.cn TC 10 Z9 14 PD JUN 15 PY 2019 VL 271 BP 251 EP 263 DI 10.1016/j.agrformet.2019.02.046 UT WOS:000468709200024 DA 2023-03-23 ER PT J AU Niu, YJ Zhu, HM Yang, SW Ma, SJ Zhou, JW Chu, B Hua, R Hua, LM AF Niu, Yujie Zhu, Huimin Yang, Siwei Ma, Sujie Zhou, Jianwei Chu, Bin Hua, Rui Hua, Limin TI Overgrazing leads to soil cracking that later triggers the severe degradation of alpine meadows on the Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Soil cracking is an important process and feature of degradation in terrestrial ecosystems. However, the patterns and causes of cracks related to alpine rangeland overgrazing have not been reported. In this study, we used a multiscale approach to investigate the distribution of soil-cracking areas at a landscape scale (217 survey sites), selected the grazing-induced parameter that was closely related to the cracks at a small scale (2013-2017), and evaluated the water infiltration due to mosaic cracking at a microscale. The results showed that cracks only formed in the alpine meadow after overstocking. Soil compaction and water content explained 89.0% of the total variance in the crack characteristics, and soil compaction was closely related to cracking. The initial infiltration rate and steady infiltration rate of the healed cracks were significantly higher than those in the raised areas in the centre of the mosaic crack patches (p < .001). We propose a new model of alpine meadow degradation considering the cracking phenomenon due to overgrazing and provide key and easy-to-measure indicators to prevent overgrazing and cracking: a residual biomass greater than 65 g m(-2) and a height greater than 6 cm, and the soil compaction should be lower than 1,044.26 +/- 188.88 kPa. These safeguard thresholds warn rangeland managers to reduce the stocking rate or improve grazing management. We suggest that the cracking stage of alpine rangelands is the most critical turning point in the process of rangeland degradation and that rangeland managers should pay more attention to crack phenomena to prevent severe degradation. C1 [Niu, Yujie; Zhu, Huimin; Zhou, Jianwei; Chu, Bin; Hua, Rui; Hua, Limin] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Gansu, Peoples R China. [Yang, Siwei] Bijie Inst Anim & Vet Sci, Bijie 551700, Peoples R China. [Ma, Sujie] Tibet Agr & Anim Husb Univ, Coll Anim Sci, Linzhi 860100, Peoples R China. RP Hua, LM (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ, Lanzhou 730070, Gansu, Peoples R China. EM hualm@gsau.edu.cn TC 34 Z9 37 PD JUN PY 2019 VL 30 IS 10 BP 1243 EP 1257 DI 10.1002/ldr.3312 UT WOS:000469980700009 DA 2023-03-23 ER PT J AU Su, XK Han, WY Liu, GH Zhang, Y Lu, HT AF Su, Xukun Han, Wangya Liu, Guohua Zhang, Yong Lu, Huiting TI Substantial gaps between the protection of biodiversity hotspots in alpine grasslands and the effectiveness of protected areas on the Qinghai-Tibetan Plateau, China SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Human activities such as livestock overgrazing, are the main reasons for the degradation of alpine grasslands and biodiversity loss on the Qinghai-Tibetan Plateau (QTP), China. With an aim toward maintaining sustainable development of alpine grasslands, protected areas (PAs) are important for biodiversity protection and to reduce the negative impacts of human activities. This study was conducted in the east of the QTP to clarify the distribution of plant-based biodiversity hotspots of alpine grasslands and to identify gaps between biodiversity hotspots protection and the effectiveness of PAs. We found that biodiversity hotspots of alpine grasslands were located in Tibetan Autonomous Prefecture of Garze (TAPG) and the Tibetan Qiang Autonomous Prefecture of Ngawa (TQAPN) in Sichuan Province, and their buffer zones were to the west of the biodiversity hotspots. PAs protected 25.930/0 (29.09 km(2)) of biodiversity hotspots and 29.17% (50.36 km(2)) of their buffer zones, respectively. Therefore, there was a substantial gap between the protection of biodiversity hotspots of alpine grasslands and the effectiveness of the PAs. According to distributions of the biodiversity hotspots and their buffer zones, replanning the boundaries of the PAs to improve their protection effectiveness would be useful for biodiversity conservation and mitigation of alpine grassland degradation. C1 [Su, Xukun; Han, Wangya; Liu, Guohua; Lu, Huiting] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing, Peoples R China. [Su, Xukun; Han, Wangya; Liu, Guohua; Lu, Huiting] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Zhang, Yong] Southwest Forestry Univ, Coll Wetlands, Natl Plateau Wetlands Res Ctr, Kunming, Yunnan, Peoples R China. RP Liu, GH (通讯作者)，18 Shuangqing Rd, Beijing, Peoples R China. EM xksu@rcees.ac.cn; hwy182005@qq.com; ghliu@rcees.ac.cn; zhy1902@126.com; luhuiting1993@163.com TC 26 Z9 28 PD JUN 1 PY 2019 VL 278 BP 15 EP 23 DI 10.1016/j.agee.2019.03.013 UT WOS:000482173500003 DA 2023-03-23 ER PT J AU Wang, J Wang, G Fu, Y Chen, XP Song, XY AF Wang, Jian Wang, Genxu Fu, Yu Chen, Xiaopeng Song, Xiaoyan TI Short-term effects of nitrogen deposition on soil respiration components in two alpine coniferous forests, southeastern Tibetan Plateau SO JOURNAL OF FORESTRY RESEARCH DT Article AB Nitrogen (N) deposition to alpine forest ecosystems is increasing gradually, yet previous studies have seldom reported the effects of N inputs on soil CO2 flux in these ecosystems. Evaluating the effects of soil respiration on N addition is of great significance for understanding soil carbon (C) budgets along N gradients in forest ecosystems. In this study, four levels of N (0, 50, 100, 150kgN ha(-1)a(-1)) were added to soil in a Picea baifouriana and an Abies georgei natural forest on the Tibetan Plateau to investigate the effect of the N inputs on soil respiration. N addition stimulated total soil respiration (Rt) and its components including heterotrophic respiration (Rh) and autotrophic respiration (Ra); however, the promoted effects declined with an increase in N application in two coniferous forests. Soil respiration rate was a little greater in the spruce forest (1.05mol CO2 m(-2)s(-1)) than that in the fir forest (0.97mol CO2 m(-2)s(-1)). A repeated measures ANOVA indicated that N fertilization had significant effects on Rt and its components in the spruce forest and Rt in the fir forest, but had no obvious effect on Rh or Ra in the fir forest. Rt and its components had significant exponential relationships with soil temperature in both forests. N addition also increased temperature sensitivity (Q(10)) of Rt and its components in the two coniferous forests, but the promotion declined as N in put increased. Important, soil moisture had great effects on Rt and its components in the spruce forest (P<0.05), but no obvious impacts were observed in the fir forest (P>0.05). Following N fertilization, Ra was significantly and positively related to fine root biomass, while Rh was related to soil enzymatic activities in both forests. The mechanisms underlying the effect of simulated N deposition on soil respiration and its components in this study may help in forecasting C cycling in alpine forests under future levels of reactive N deposition. C1 [Wang, Jian] China West Normal Univ, Land & Resource Coll, Nanchong 637002, Sichuan, Peoples R China. [Wang, Genxu; Chen, Xiaopeng; Song, Xiaoyan] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, 9,Block 4,Renminnanlu Rd, Chengdu 610041, Sichuan, Peoples R China. [Fu, Yu] China West Normal Univ, Dept Polit & Adm, Nanchong 637002, Sichuan, Peoples R China. [Chen, Xiaopeng; Song, Xiaoyan] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. RP Wang, G (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, 9,Block 4,Renminnanlu Rd, Chengdu 610041, Sichuan, Peoples R China. EM wanggx@imde.ac.cn TC 9 Z9 10 PD JUN PY 2019 VL 30 IS 3 BP 1029 EP 1041 DI 10.1007/s11676-018-0678-6 UT WOS:000466148600027 DA 2023-03-23 ER PT J AU Zhang, C Zhang, DW Deng, XG Tian, ZH Zou, LJ Li, MQ Tang, XY Li, DX Zhang, CB Yan, JJ Zhao, WJ Liu, BH Bai, SQ Lin, HH AF Zhang, Chao Zhang, Da-Wei Deng, Xing-Guang Tian, Zhi-Hui Zou, Li-Juan Li, Ming-Qun Tang, Xiao-Ya Li, Da-Xu Zhang, Chang-Bing Yan, Jia-Jun Zhao, Wen-Ji Liu, Bao-Hui Bai, Shi-Qie Lin, Hong-Hui TI Various adaptations of meadow forage grasses in response to temperature changes on the Qinghai-Tibet Plateau, China SO PLANT GROWTH REGULATION DT Article AB Global warming is considered a pivotal environmental factor influencing the growth of meadow forage grasses and the balance of alpine meadow ecosystems, especially on the Qinghai-Tibet Plateau. The objective of this study was to evaluate the adaptability of introducing and restoring forage grass species on the Hongyuan prairie in response to temperature changes. Based on the analysis of photosynthetic parameters such as P-N, G(S), C-I, V-cmax, J(max), F-v/F-m, F-v/F-m, q(P), and phi(PSII) for different forage grass species grown in the alpine meadow area, we found the local native grass species had photosynthetic capacities that were more sensitive to temperature changes than those of the introduced species. Among the several kinds of introduced forage grasses, reed canary grass showed the greatest redistribution of absorbed light energy when light energy exceeded the utilization capacity. Reed canary grass also showed an increased distribution of biomass in its roots and a decreased distribution of biomass in its stems. Overall, reed canary grass is a potential resource to address grassland desertification and to restore or reconstruct meadow grass ecosystems in accordance with the temperature changes. C1 [Zhang, Chao; Zhang, Da-Wei; Deng, Xing-Guang; Tian, Zhi-Hui; Zou, Li-Juan; Li, Ming-Qun; Tang, Xiao-Ya; Lin, Hong-Hui] Sichuan Univ, Coll Life Sci, State Key Lab Hydraul & Mt River Engn, Minist Educ,Key Lab Bioresource & Ecoenvironm, Chengdu 610064, Sichuan, Peoples R China. [Li, Da-Xu; Zhang, Chang-Bing; Yan, Jia-Jun; Zhao, Wen-Ji; Bai, Shi-Qie] Sichuan Acad Grassland Sci, Chengdu 611731, Sichuan, Peoples R China. [Zhang, Chao] Liupanshui Normal Coll, Liupanshui 553000, Guizhou, Peoples R China. [Liu, Bao-Hui] Guangzhou Univ, Sch Life Sci, Guangzhou 510006, Guangdong, Peoples R China. RP Lin, HH (通讯作者)，Sichuan Univ, Coll Life Sci, State Key Lab Hydraul & Mt River Engn, Minist Educ,Key Lab Bioresource & Ecoenvironm, Chengdu 610064, Sichuan, Peoples R China.; Bai, SQ (通讯作者)，Sichuan Acad Grassland Sci, Chengdu 611731, Sichuan, Peoples R China. EM baiturf@qq.com; hhlin@scu.edu.cn TC 6 Z9 8 PD JUN PY 2019 VL 88 IS 2 BP 181 EP 193 DI 10.1007/s10725-019-00499-x UT WOS:000467934900008 DA 2023-03-23 ER PT J AU Zhu, SS Dai, GH Ma, T Chen, LT Chen, DM Lu, XT Wang, XB Zhu, JT Zhang, YJ Bai, YF Han, XG He, JS Feng, XJ AF Zhu, Shanshan Dai, Guohua Ma, Tian Chen, Litong Chen, Dima Lu, Xiaotao Wang, Xiaobo Zhu, Juntao Zhang, Yangjian Bai, Yongfei Han, Xingguo He, Jin-Sheng Feng, Xiaojuan TI Distribution of lignin phenols in comparison with plant-derived lipids in the alpine versus temperate grassland soils SO PLANT AND SOIL DT Article AB AimsAs a major plant-derived soil organic carbon (SOC) component, lignin-derived phenolic compounds show varying biogeochemical characteristics compared to plant-derived lipid moieties. Comparing their distribution patterns can provide information on mechanisms governing SOC preservation and dynamics. However, the large-scale distribution pattern and stability of lignin versus plant-derived lipids are still poorly constrained. Here we investigated the distribution of lignin phenols versus plant-derived lipids in the surface soils across the alpine versus temperate grasslands of China and Mongolia.MethodsLignin phenols were isolated by cupric oxide oxidation method and compared with the previously analyzed plant-derived lipids (cutin and suberin). A comprehensive list of environmental variables was compiled to disentangle the climatic, edaphic and vegetation influences on lignin phenols' distribution in the soil.ResultsLignin phenols showed similar SOC-normalized concentrations in the alpine and temperate grassland soils despite a higher plant input to the latter, suggesting better lignin preservation in the cold region. However, compared with plant-derived lipids (cutin and suberin), lignin seems to be less stabilized. The variation of lipid versus lignin components is mainly related to climate (particularly aridity) in the alpine grassland soils, while the relative abundance of plant lipids and lignin phenols is more related to reactive mineral contents in the temperate grassland soils.ConclusionsLignin contributes differentially to SOC accumulation in the alpine and temperate soils: while lignin seems to be better preserved in the cold region, lignin phenols decrease relative to other carbon components with SOC accrual in the temperate region. Overall, lignin distribution and fate may be more sensitive to carbon source variations than temperature shifts in the grasslands. C1 [Zhu, Shanshan; Dai, Guohua; Ma, Tian; Chen, Dima; Bai, Yongfei; Han, Xingguo; Feng, Xiaojuan] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Zhu, Shanshan; Ma, Tian; Zhang, Yangjian; Bai, Yongfei; Han, Xingguo; Feng, Xiaojuan] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. [Chen, Litong] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Qinghai, Peoples R China. [Lu, Xiaotao; Wang, Xiaobo] Chinese Acad Sci, Inst Appl Ecol, Key Lab Forest Ecol & Management, Shenyang 110016, Liaoning, Peoples R China. [Zhu, Juntao; Zhang, Yangjian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [He, Jin-Sheng] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland & Agroecosyst, Lanzhou 730020, Gansu, Peoples R China. [He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. RP Feng, XJ (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. EM xfeng@ibcas.ac.cn TC 13 Z9 13 PD JUN PY 2019 VL 439 IS 1-2 SI SI BP 325 EP 338 DI 10.1007/s11104-019-04035-8 UT WOS:000474429100022 DA 2023-03-23 ER PT J AU Jin, JX Ma, XL Chen, H Wang, H Kang, XM Wang, XF Wang, Y Yong, B Guo, FS AF Jin, Jiaxin Ma, Xuanlong Chen, Huai Wang, Han Kang, Xiaoming Wang, Xufeng Wang, Ying Yong, Bin Guo, Fengsheng TI Grassland production in response to changes in biological metrics over the Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB A clear interannual variability in annual production of grasslands (termed AEVI) has been reported over the Tibetan Plateau (TP), but the underlying mechanism has not been fully understood. Here, we explained the interannual variability of AEVI during 2001-2015 by two phenological metrics (the start and end of the growing season, termed SOS and EOS, respectively) and one physiological metric (the maximum capacity of canopy light absorbance, termed MEVI) using MODIS Enhanced Vegetation Index (EVI) data over the TP. The results showed that the interannual variability of AEVI can be well attributed to not only the trends of, but also the sensitivities of AEVI to, the selected biological metrics. On the one hand, the advancing SOS and delaying EOS dominated the study area while both increased and decreased MEVI were observed. On the other hand, the AEVI responded negatively to the SOS and positively to the EOS and MEVI, exhibiting significant variations along the temperature and precipitation gradients. Hence, the current interannual variability of SOS and EOS mainly increased the AEVI; meanwhile, both enhancement and suppression of the interannual variability of MEVI to the AEVI were widespread over the TP. Overall, the interannual variability of MEVI mostly contributed to that of the AEVI, indicating a dominant role of the physiological metric rather than phenological metrics in carbon gain of TP grasslands. The achievements of this study are helpful to understand the underlying biological causes of the interannual variability of grassland production over the TP. (C) 2019 Elsevier B.V. All rights reserved. C1 [Jin, Jiaxin; Yong, Bin] Hohai Univ, State Key Lab Hydrol Water Resources & Hydraul En, Nanjing, Jiangsu, Peoples R China. [Jin, Jiaxin; Yong, Bin; Guo, Fengsheng] Hohai Univ, Sch Earth Sci & Engn, Nanjing, Jiangsu, Peoples R China. [Ma, Xuanlong] German Ctr Integrat Biodivers Res iDiv, D-04103 Leipzig, Germany. [Ma, Xuanlong] Max Planck Inst Biogeochem, Jena, Germany. [Chen, Huai] Chinese Acad Sci, Chengdu Inst Biol, Chengdu, Sichuan, Peoples R China. [Wang, Han] Tsinghua Univ, Dept Earth Syst Sci, Beijing, Peoples R China. [Kang, Xiaoming] Chinese Acad Forestry, Inst Wetland Res, Beijing Key Lab Wetland Serv & Restorat, Beijing, Peoples R China. [Wang, Xufeng] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou, Gansu, Peoples R China. [Wang, Ying] Sanjiang Univ, Sch Culture Ind & Tourism Management, Nanjing, Jiangsu, Peoples R China. RP Jin, JX (通讯作者)，Hohai Univ, State Key Lab Hydrol Water Resources & Hydraul En, Nanjing, Jiangsu, Peoples R China. EM jiaxinking@hhu.edu.cn TC 8 Z9 9 PD MAY 20 PY 2019 VL 666 BP 641 EP 651 DI 10.1016/j.scitotenv.2019.02.293 UT WOS:000463180700061 DA 2023-03-23 ER PT J AU Li, ZF Gao, JX Wen, LQ Zou, CX Feng, CY Li, DQ Xu, DL AF Li, Zhongfei Gao, Jixi Wen, Linqin Zou, Changxin Feng, Chaoyang Li, Daiqing Xu, Delin TI Dynamics of Soil Respiration in Alpine Wetland Meadows Exposed to Different Levels of Degradation in the Qinghai-Tibet Plateau, China SO SCIENTIFIC REPORTS DT Article AB The effects of degradation of alpine wetland meadow on soil respiration (Rs) and the sensitivity of Rs to temperature (Q(10)) were measured in the Napa Lake region of Shangri-La on the southeastern edge of the Qinghai-Tibet Plateau. Rs was measured for 24 h during each of three different stages of the growing season on four different degraded levels. The results showed: (1) peak Rs occurred at around 5:00 p.m., regardless of the degree of degradation and growing season stage, with the maximum Rs reaching 10.05 mu mol.m(-2).s(-1) in non-degraded meadows rather than other meadows; (2) the daily mean Rs value was 7.14-7.86 mu mol.m(-2.)s(-1) during the mid growing season in non-degraded meadows, and declined by 48.4-62.6% when degradation increased to the severely degraded level; (3) Q(10) ranged from 7.1-11.3 in non-degraded meadows during the mid growing season, 5.5-8.0 and 6.2-8.2 during the early and late growing seasons, respectively, and show a decline of about 50% from the non-degraded meadows to severely degraded meadows; (4) Rs was correlated significantly with soil temperature at a depth of 0-5 cm (p < 0.05) on the diurnal scale, but not at the seasonal scale; (5) significant correlations were found between Rs and soil organic carbon (SOC), between biomass and SOC, and between Q(10) and Rs (p < 0.05), which indicates that biomass and SOC potentially impact Q(10). The results suggest that vegetation degradation impact both Rs and Q(10) significantly. Also, we speculated that Q(10) of alpine wetland meadow is probable greater at the boundary region than inner region of the Qinghai-Tibet Plateau, and shoule be a more sensitive indicator in the studying of climate change in this zone. C1 [Li, Zhongfei; Wen, Linqin] Southwest Forestry Univ, Coll Ecol & Environm, Kunming 650224, Yunnan, Peoples R China. [Li, Zhongfei; Gao, Jixi; Zou, Changxin; Xu, Delin] Minist Ecol & Environm, Nanjing Inst Environm Sci, Nanjing 210042, Jiangsu, Peoples R China. [Feng, Chaoyang; Li, Daiqing] Chinese Res Inst Environm Sci, Beijing 100012, Peoples R China. [Feng, Chaoyang; Li, Daiqing] State Environm Protect Key Lab Reg Ecoproc & Func, Beijing 100012, Peoples R China. RP Gao, JX (通讯作者)，Minist Ecol & Environm, Nanjing Inst Environm Sci, Nanjing 210042, Jiangsu, Peoples R China. EM gjx@nies.org TC 6 Z9 9 PD MAY 16 PY 2019 VL 9 AR 7469 DI 10.1038/s41598-019-43904-1 UT WOS:000468026100011 DA 2023-03-23 ER PT J AU Cao, YN Wu, JS Zhang, XZ Niu, B Li, M Zhang, YJ Wang, XT Wang, ZP AF Cao, Yanan Wu, Jianshuang Zhang, Xianzhou Niu, Ben Li, Meng Zhang, Yanjie Wang, Xiangtao Wang, Zhipeng TI Dynamic forage-livestock balance analysis in alpine grasslands on the Northern Tibetan Plateau SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Forage-livestock balance is important for sustainable management of alpine grasslands under global change, but the robustness of diverse algorithms for assessing forage-livestock balance is still unclear. This study compiled long-term (2009-2014) field observations of aboveground biomass (AGB). Using climate and remote sensing data, we evaluated the inter-annual dynamics of the forage-livestock balance on the Northern Tibetan Plateau (NIP). Here, we assumed that AGB dynamics in fenced grasslands (AGB(F)) is only driven by climate change; whereas AGB dynamics in open grasslands grazed by livestock (AGB(G)) is driven by a combination of climate change and human activities. Thus, human-induced change in AGB (AGB(H)) could be estimated via the difference between AGB(F) and AGB(G). Furthermore, differences in the temporal trends between AGB(F) and AGB(H) could indicate the state of forage-livestock balance, overgrazed or not, in alpine grasslands. Our results showed that the overall status of the forage-livestock balance from 2000 to 2006 was overgrazed owing to poor climatic conditions. Ecological projects and economic policies for alpine grassland conservation had not been implemented at that time, which also resulted in local overgrazing. From 2006 to 2014, the alpine grasslands in some areas were in a less-grazed state. We suggest that the livestock number could potentially increase in northern NTP and should be reduced or strictly controlled to maintain the balance between livestock and forage in the southern and southeast areas. In conclusion, the results of this study suggest that the evaluation of the forage-livestock balance in the NTP should include the local climatic conditions and make better use of grassland resources while ensuring ecological security. C1 [Cao, Yanan; Wu, Jianshuang; Zhang, Xianzhou; Niu, Ben; Li, Meng; Zhang, Yanjie; Wang, Xiangtao; Wang, Zhipeng] Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Cao, Yanan; Li, Meng; Zhang, Yanjie; Wang, Xiangtao; Wang, Zhipeng] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wu, Jianshuang] Free Univ Berlin, Inst Biol, Biodivers Theoret Ecol, Altensteinstr 34, D-14195 Berlin, Germany. RP Zhang, XZ (通讯作者)，Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM zhangxz@igsnrr.ac.cn TC 25 Z9 34 PD MAY 15 PY 2019 VL 238 BP 352 EP 359 DI 10.1016/j.jenvman.2019.03.010 UT WOS:000464296400039 DA 2023-03-23 ER PT J AU Li, CX de Jong, R Schmid, B Wulf, H Schaepman, ME AF Li, Chengxiu de Jong, Rogier Schmid, Bernhard Wulf, Hendrik Schaepman, Michael E. TI Spatial variation of human influences on grassland biomass on the Qinghai-Tibetan plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB An improved understanding of increased human influence on ecosystems is needed for predicting ecosystem processes and sustainable ecosystem management. We studied spatial variation of human influence on grassland ecosystems at two scales across the Qinghai-Tibetan Plateau (QTP), where increased human activities may have led to ecosystem degradation. At the 10 km scale, we mapped human-influenced spatial patterns based on a hypothesis that spatial patterns of biomass that could not be attributed to environmental variables were likely correlated to human activities. In part this hypothesis could be supported via a positive correlation between biomass unexplained by environmental variables and livestock density. At the 500 m scale, using distance to settlements within a radius of 8 km as a proxy of human-influence intensity, we found both negatively human-influenced areas where biomass decreased closer to settlements (regions with higher livestock density) and positively human-influenced areas where biomass increased closer to settlements (regions with lower livestock density). These results suggest complex relationships between livestock grazing and biomass, varying between spatial scales and regions. Grazing may boost biomass production across the whole QTP at the 10 km scale. However, overgrazing may reduce it near settlements at the 500 m scale. Our approach of mapping and understanding human influence on ecosystems at different scales could guide pasture management to protect grassland in vulnerable regions on the QTP and beyond. (c) 2019 Elsevier B.V. All rights reserved. C1 [Li, Chengxiu; de Jong, Rogier; Schmid, Bernhard; Wulf, Hendrik; Schaepman, Michael E.] Univ Zurich, Remote Sensing Labs, Winterthurerstr 190, CH-8057 Zurich, Switzerland. RP Li, CX (通讯作者)，Univ Zurich, Remote Sensing Labs, Winterthurerstr 190, CH-8057 Zurich, Switzerland. EM chengxiu.li@geo.uzh.ch TC 29 Z9 30 PD MAY 15 PY 2019 VL 665 BP 678 EP 689 DI 10.1016/j.scitotenv.2019.01.321 UT WOS:000460628600069 DA 2023-03-23 ER PT J AU Zhang, T Xu, MJ Zhang, YJ Zhao, TH An, TT Li, YG Sun, Y Chen, N Zhao, TT Zhu, JT Yu, GR AF Zhang, Tao Xu, Mingjie Zhang, Yangjian Zhao, Tianhong An, Tingting Li, Yingge Sun, Yi Chen, Ning Zhao, Tingting Zhu, Juntao Yu, Guirui TI Grazing-induced increases in soil moisture maintain higher productivity during droughts in alpine meadows on the Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Grazing is the primary land use practice in alpine ecosystems on the Tibetan Plateau. However, it remains unclear how grazing regulates levels of carbon and the water cycle in this ecosystem. A paired set of eddy covariance systems were set in adjacent fenced (FM) and grazed meadows (GM) to explore the grazing effects on alpine meadows. Aboveground biomass removed by grazing caused declines in grass transpiration (T), whereas the evaporation (E) was enhanced because of greater exposure to radiation, which in turn led to higher evapotranspiration (ET) in GM. However, the deep-layer soil moisture remained high because of the effects of mattic epipedon, which worked as a water-resistant layer. Therefore, the deep-layer soil moisture in GM was higher than that in FM because of decreased water consumption caused by the grazing-induced reduction in leaf area in GM. As a consequence, the deep-layer soil in GM could provide more water to help plants endure droughts. Additionally, grazing enhanced the sensitivity of productivity to soil moisture during the wet season in drought years, which could restore grassland productivity more quickly after droughts. Therefore, grazing could help this fragile ecosystem to withstand droughts to some extent and maintain higher productivity. This may provide us with an ecological approach for confronting global climate change. C1 [Zhang, Tao; Xu, Mingjie; Zhao, Tianhong; An, Tingting; Li, Yingge; Sun, Yi; Zhao, Tingting] Shenyang Agr Univ, Coll Agron, Postdoctoral Res Stn Crop Sci, Shenyang 110866, Liaoning, Peoples R China. [Zhang, Yangjian; Chen, Ning; Zhu, Juntao; Yu, Guirui] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Zhang, Tao; Zhang, Yangjian; Chen, Ning; Zhu, Juntao] Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhang, Yangjian] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. RP Zhang, YJ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China.; Zhang, YJ (通讯作者)，Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China.; Zhang, YJ (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. EM zhangyj@igsnrr.ac.cn TC 35 Z9 38 PD MAY 15 PY 2019 VL 269 BP 249 EP 256 DI 10.1016/j.agrformet.2019.02.022 UT WOS:000463120900023 DA 2023-03-23 ER PT J AU Ran, QW Hao, YB Xia, AQ Liu, WJ Hu, RH Cui, XY Xue, K Song, XN Xu, C Ding, BY Wang, YF AF Ran, Qinwei Hao, Yanbin Xia, Anquan Liu, Wenjun Hu, Ronghai Cui, Xiaoyong Xue, Kai Song, Xiaoning Xu, Cong Ding, Boyang Wang, Yanfen TI Quantitative Assessment of the Impact of Physical and Anthropogenic Factors on Vegetation Spatial-Temporal Variation in Northern Tibet SO REMOTE SENSING DT Article AB The alpine grassland on the Qinghai-Tibet Plateau covers an area of about 1/3 of China's total grassland area and plays a crucial role in regulating grassland ecological functions. Both environmental changes and irrational use of the grassland can result in severe grassland degradation in some areas of the Qinghai-Tibet Plateau. However, the magnitude and patterns of the physical and anthropogenic factors in driving grassland variation over northern Tibet remain debatable, and the interactive influences among those factors are still unclear. In this study, we employed a geographical detector model to quantify the primary and interactive impacts of both the physical factors (precipitation, temperature, sunshine duration, soil type, elevation, slope, and aspect) and the anthropogenic factors (population density, road density, residential density, grazing density, per capita GDP, and land use type) on vegetation variation from 2000 to 2015 in northern Tibet. Our results show that the vegetation index in northern Tibet significantly decreased from 2000 to 2015. Overall, the stability of vegetation types was sorted as follows: the alpine scrub > the alpine steppe > the alpine meadow. The physical factors, rather than the anthropogenic factors, have been the primary driving factors for vegetation dynamics in northern Tibet. Specifically, meteorological factors best explained the alpine meadow and alpine steppe variation. Precipitation was the key factor that influenced the alpine meadow variation, whereas temperature was the key factor that contributed to the alpine steppe variation. The anthropogenic factors, such as population density, grazing density and per capita GDP, influenced the alpine scrub variation most. The influence of population density is highly similar to that of grazing density, which may provide convenient access to simplify the study of the anthropogenic activities in the Tibet plateau. The interactions between the driving factors had larger effects on vegetation than any single factor. In the alpine meadow, the interaction between precipitation and temperature can explain 44.6% of the vegetation variation. In the alpine scrub, the interaction between temperature and GDP was the highest, accounting for 27.5% of vegetation variation. For the alpine steppe, the interaction between soil type and population density can explain 29.4% of the vegetation variation. The highest value of vegetation degradation occurred in the range of 448-469 mm rainfall in the alpine meadow, 0.61-1.23 people/km(2) in the alpine scrub and -0.83-0.15 degrees C in the alpine steppe, respectively. These findings could contribute to a better understanding of degradation prevention and sustainable development of the alpine grassland ecosystem in northern Tibet. C1 [Ran, Qinwei; Hao, Yanbin; Xia, Anquan; Hu, Ronghai; Cui, Xiaoyong; Xue, Kai; Song, Xiaoning; Xu, Cong; Ding, Boyang; Wang, Yanfen] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Hao, Yanbin; Cui, Xiaoyong; Xue, Kai; Wang, Yanfen] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Liu, Wenjun] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China. [Hu, Ronghai] Univ Strasbourg, CNRS, UMR 7357, ICube Lab, 300 Bd Sebastien Brant,CS 10413, F-67412 Illkirch Graffenstaden, France. [Wang, Yanfen] Chinese Acad Sci, Beijing Inst Life Sci, Res Network Global Change Biol, Beijing 100101, Peoples R China. RP Wang, YF (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China.; Wang, YF (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China.; Wang, YF (通讯作者)，Chinese Acad Sci, Beijing Inst Life Sci, Res Network Global Change Biol, Beijing 100101, Peoples R China. EM ranqinwei16@mails.ucas.ac.cn; ybhao@ucas.ac.cn; xiaanquan17@mails.ucas.ac.cn; Liuwj@radi.ac.cn; sea@mail.bnu.edu.cn; cuixy@ucas.ac.cn; xuekai@ucas.ac.cn; songxn@ucas.ac.cn; xucong17@mails.ucas.ac.cn; dingboyang18@mails.ucas.ac.cn; yfwang@ucas.ac.cn TC 27 Z9 30 PD MAY 2 PY 2019 VL 11 IS 10 AR 1183 DI 10.3390/rs11101183 UT WOS:000480524800041 DA 2023-03-23 ER PT J AU Bai, W Wang, GX Xi, JY Liu, YW Yin, PS AF Bai, Wei Wang, Genxu Xi, Jingyang Liu, Yongwan Yin, Pengsong TI Short-term responses of ecosystem respiration to warming and nitrogen addition in an alpine swamp meadow SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB Information regarding the interactive effects of global warming and increasing nitrogen (N) deposition on CO2 emissions in the alpine grassland ecosystem is scarce, especially in the permafrost region of the Qinghai-Tibetan Plateau. We conducted a manipulative field experiment in an alpine swamp meadow to investigate the responses of ecosystem respiration (ER) to simulated warming and N addition. Results showed that the interaction between warming and N addition significantly increased ER by 41.3-239.6%, which might be related to the enhancements in plant autotrophic respiration and soil microbial biomass and activity. The correlations between ER and a single hydrothermic factor tended to be weakened with the increasing complexity of the treatment method. The drought stress on CO2 emissions was not found due to the thawing of the permafrost and the upward diffusion of soil moisture, thus air temperature combined with soil temperature explained 80% of the ER fluctuations. Meanwhile, warming increased the aboveground biomass (AGB) and belowground biomass (BGB) by 44.2-68.1% and 48.1-82.6%, respectively, suggesting that more biomass was allocated to the belowground components. N addition increased AGB by 21.2-30.3%, while there was no significant effect on BGB. Warming combined with N addition strongly increased AGB and BGB by 52.0-159.5% and 59.0-102.1%, respectively. These results indicated that plant production and allocation pattern might also be important factors affecting CO2 emissions. In addition, warming alone and warming combined with N addition increased soil microbial biomass carbon (MBC) by 19.1-90.7% and 28.1-80.4%, respectively, and the enhancement in soil microbial biomass and activity might promote the release of soil carbon. C1 [Bai, Wei; Xi, Jingyang; Liu, Yongwan; Yin, Pengsong] Lanzhou Jiaotong Univ, Sch Environm & Municipal Engn, Lanzhou 730070, Gansu, Peoples R China. [Wang, Genxu] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China. RP Bai, W (通讯作者)，Lanzhou Jiaotong Univ, Sch Environm & Municipal Engn, Lanzhou 730070, Gansu, Peoples R China. EM baiwei915@163.com TC 6 Z9 8 PD MAY-JUN PY 2019 VL 92 BP 16 EP 23 DI 10.1016/j.ejsobi.2019.04.003 UT WOS:000469158800003 DA 2023-03-23 ER PT J AU Chen, SL Huang, YF Gao, S Wang, GQ AF Chen, Shiliu Huang, Yuefei Gao, Shuai Wang, Guangqian TI Impact of physiological and phenological change on carbon uptake on the Tibetan Plateau revealed through GPP estimation based on spaceborne solar-induced fluorescence SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Although gross primary production (GPP) is an essential proxy for reflecting terrestrial ecosystem function, GPP estimation at regional scale on the Tibetan Plateau (TP) is constrained by the lack of ground observations. Moreover, how climate-induced phenological and physiological change further affects carbon uptake in this region remains unclear. In this study, we first estimated GPP at 8-day intervals and a 0.5 degrees resolution from 2007 to 2015 over the TP based on an improved approach and GOME-2 sun-induced fluorescence (SIF) retrievals. The obtained SIF-based GPP coincided well with flux observations and two state of the art GPP products, with a regional carbon uptake of 0.62 +/- 0.04 PgC year(-1) or 307 +/- 22 gC m(-2) year(-1). With the SIF-based GPP, two phenological indicators (start and end date of the growing season, i.e., SGS and EGS) and one physiological indicator (maximum photosynthesis capacity, GPP(max)) were identified and their relative contributions to inter-annual GPP variability were further quantitatively separated using a multiple regression model. Advanced SGS, delayed EGS, and increasing GPPmax can all enhance carbon uptake and a combination of the three indicators can explain 72 +/- 20% of GPP inter-annual variability. The response of annual GPP to phenological and physiological variations has significant altitude dependence, as the decline of annual GPP in most of the area is dominated by the GPPmax decline, while the increase of annual GPP in the high-altitude area is dominated by the advanced SGS. The response of all three indicators to both temperature and precipitation variation has great spatial heterogeneity. Our study suggests that remote sensing of SIF can provide a unique opportunity to estimate GPP in regions with a lack of ground observations and that our enhanced understanding of the impact of the climate-induced phenological and physiological change on GPP variability in alpine ecosystems can improve GPP estimation in a changing climate. (C) 2019 Elsevier B.V. All rights reserved. C1 [Chen, Shiliu; Huang, Yuefei; Gao, Shuai; Wang, Guangqian] Tsinghua Univ, Dept Hydraul Engn, State Key Lab Hydrosci & Engn, Beijing 100084, Peoples R China. [Huang, Yuefei] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. RP Chen, SL; Huang, YF (通讯作者)，Tsinghua Univ, Dept Hydraul Engn, State Key Lab Hydrosci & Engn, Beijing 100084, Peoples R China. EM csl16@mails.tsinghua.edu.cn; yuefeihuang@tsinghua.edu.cn TC 20 Z9 23 PD MAY 1 PY 2019 VL 663 BP 45 EP 59 DI 10.1016/j.scitotenv.2019.01.324 UT WOS:000459858500005 DA 2023-03-23 ER PT J AU Du, YG Shu, K Guo, XW Zhu, PJ AF Du, Yangong Shu, Kai Guo, Xiaowei Zhu Pengjin TI Moderate Grazing Promotes Grassland Nitrous Oxide Emission by Increasing Ammonia-Oxidizing Archaea Abundance on the Tibetan Plateau SO CURRENT MICROBIOLOGY DT Article AB Grasslands are suffering from long-term overgrazing because of the population inflation. Furthermore, nitrous oxide (N2O) is a major greenhouse gas that also depletes stratospheric ozone. However, the emission rate of grassland N2O and underlying mechanisms remained unclear under different grazing intensities. We conducted a field manipulation under four grazing intensities to compare its N2O fluxes and main affected factors. It was indicated that alpine meadow N2O emission rates increased from 39.7 +/- 3.1 to 47.8 +/- 2.3 mu g m(-2) h(-1) (p < 0.05), then decreased to 43.4 +/- 4.1 and 32.9 +/- 1.4 mu g m(-2) h(-1) with grazing intensity increasing from 4 to 8, 12 and 16 sheep ha-1, respectively. Multiple-stepwise regression analysis indicated that the predominant affected soil factors were separately TN and BD, pH and BD, also pH and BD, SOC and BD. Simple linear regression models revealed that ammonia-oxidizing archaea (AOA) contributed much to N2O emission (R-2 = 0.77). Additionally, the R-2 coefficient of linear regression was 0.87 between nosZ genes and N2O emission rates in alpine meadow. Much attention should be paid to protecting alpine meadow from degradation to mitigate N2O emission source on the Tibetan Plateau. C1 [Du, Yangong; Shu, Kai; Guo, Xiaowei] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining, Qinghai, Peoples R China. [Shu, Kai] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhu Pengjin] Guangxi Inst Subtrop Crops, Nanning, Peoples R China. RP Du, YG (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Reg, Xining, Qinghai, Peoples R China. EM ygdu@nwipb.cas.cn TC 8 Z9 12 PD MAY PY 2019 VL 76 IS 5 BP 620 EP 625 DI 10.1007/s00284-019-01668-x UT WOS:000464849800013 DA 2023-03-23 ER PT J AU Li, YM Jiang, LL Lv, WW Cui, SJ Zhang, LR Wang, Q Meng, FD Li, BW Liu, PP Suonan, J Renzeng, WN Li, XN Luo, CY Zhang, ZH Dorji, T Wang, YF Wang, SP AF Li, Yaoming Jiang, Lili Lv, Wangwang Cui, Shujuan Zhang, Lirong Wang, Qi Meng, Fandong Li, Bowen Liu, Peipei Suonan, Ji Renzeng, Wangmu Li, Xine Luo, Caiyun Zhang, Zhenhua Dorji, Tsechoe Wang, Yanfen Wang, Shiping TI Fungal pathogens pose a potential threat to animal and plant health in desertified and pika-burrowed alpine meadows on the Tibetan Plateau SO CANADIAN JOURNAL OF MICROBIOLOGY DT Article AB Intact Tibetan meadows provide significant defense against soil-borne pathogen dispersal. However, dramatic meadow degradation has been observed due to climate change and pika damage, but their impacts on soil-borne pathogens are still unclear. With approximately 40% of the world's population living in Tibetan Plateau and its downstream watersheds, this lack of knowledge should be of great concern. Here, we used Illumina amplicon sequencing to characterize the changes in potential human, domestic animal, plant, and zoonotic bacterial and fungal pathogens in nondegraded, desertified, and pika-burrowed meadows. The relative abundance of bacterial domestic animal pathogens and zoonotic pathogens were significantly increased by desertification. Pika burrowing significantly increased the relative abundance of bacterial human pathogens and zoonotic pathogens. The species richness and relative abundance of fungal pathogens was significantly increased by desertification and pika burrowing. Accordingly, fungal plant and animal pathogens categorized by FUNGuid significantly increased in desertified and pika-burrowed meadows. Soil chemical and plant properties explained 38% and 64% of the bacterial and fungal pathogen community variance, respectively. Therefore, our study indicates for the first time that both alpine meadow desertification and pika burrowing could potentially increase infectious disease risks in the alpine ecosystem, especially for fungal diseases. C1 [Li, Yaoming; Jiang, Lili; Lv, Wangwang; Cui, Shujuan; Zhang, Lirong; Wang, Qi; Meng, Fandong; Li, Bowen; Liu, Peipei; Suonan, Ji; Renzeng, Wangmu; Li, Xine; Dorji, Tsechoe; Wang, Shiping] Chinese Acad Sci, Key Lab Alpine Ecol, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. [Lv, Wangwang; Cui, Shujuan; Wang, Qi; Li, Bowen; Liu, Peipei; Renzeng, Wangmu; Wang, Yanfen] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Luo, Caiyun; Zhang, Zhenhua] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Northwest Inst Plateau Biol, Xining 810008, Qinghai, Peoples R China. [Dorji, Tsechoe; Wang, Shiping] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Dorji, Tsechoe; Wang, Shiping] Tibet Univ, Naqu Integrated Observat & Res Stn Ecol & Environ, Lasa 850012, Peoples R China. [Dorji, Tsechoe; Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lasa 850012, Peoples R China. RP Li, YM; Wang, SP (通讯作者)，Chinese Acad Sci, Key Lab Alpine Ecol, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China.; Wang, SP (通讯作者)，CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China.; Wang, SP (通讯作者)，Tibet Univ, Naqu Integrated Observat & Res Stn Ecol & Environ, Lasa 850012, Peoples R China.; Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Lasa 850012, Peoples R China. EM liyaoming@itpcas.ac.cn; wangsp@itpcas.ac.cn TC 3 Z9 4 PD MAY PY 2019 VL 65 IS 5 BP 365 EP 376 DI 10.1139/cjm-2018-0338 UT WOS:000466166200004 DA 2023-03-23 ER PT J AU Pang, Z Jiang, LL Wang, SP Xu, XL Rui, YC Zhang, ZH Luo, CY Wang, YF AF Pang, Zhe Jiang, Lili Wang, Shiping Xu, Xingliang Rui, Yichao Zhang, Zhenhua Luo, Caiyun Wang, Yanfen TI Differential response to warming of the uptake of nitrogen by plant species in non-degraded and degraded alpine grasslands SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Purpose Chemical niche differentiation and changes in the dominance of plant species have been proposed as mechanisms for the coexistence of different types of plants. We explored how dominant plant species take up ammonium (NH4+), nitrate (NO3-), and glycine under conditions of warming and soil degradation in alpine grasslands. Materials and methods Open-top chambers were used to simulate warming in degraded and non-degraded plots in an alpine grassland ecosystem on the Tibetan Plateau. Plant species were selected in both non-degraded (Kobresia pygmaea and Aster tataricus) and degraded (Aster tataricus and Chenopodium glaucum) plots. Short-term N-15-labeling experiments with NH4+-N, NO3--N, and glycine ((CN)-C-13-N-15-glycine) were conducted in each of four subplots with water alone as the control. Results and discussion All of the selected plant species took up both organic and inorganic forms of N in the K. pygmaea grassland. Warming increased the uptake of glycine-N by the dominant species, whereas the uptake of NH4+-N by the non-dominant species increased in both non-degraded and degraded grasslands. Warming changed the N uptake preference of A. tataricus from NO3--N to NH4+-N in non-degraded grasslands, but did not change the preference of A. tataricus under degraded conditions. This suggests that degradation can affect the preference of different plant species for particular forms of N as a response to warming. Conclusions Plants in K. pygmaea grasslands take up organic N, although inorganic N is the dominant form of N used. The effects of warming on the uptake of N by plants varied with species, the form of N, and the degradation of the grassland. Degradation modified the effect of warming on the preference of plants for different forms of N. Different plant species developed different patterns for the uptake of N in both non-degraded and degraded plots, which may facilitate their coexistence in alpine grasslands. C1 [Pang, Zhe; Wang, Yanfen] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Jiang, Lili; Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. [Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Rui, Yichao] Univ Wisconsin, Dept Soil Sci, Madison, WI 53706 USA. [Zhang, Zhenhua; Luo, Caiyun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Qinghai, Peoples R China. RP Wang, YF (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China.; Jiang, LL (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China. EM lljiang@itpcas.ac.cn; yfwang@ucas.ac.cn TC 14 Z9 15 PD MAY PY 2019 VL 19 IS 5 BP 2212 EP 2221 DI 10.1007/s11368-019-02255-0 UT WOS:000464836300007 DA 2023-03-23 ER PT J AU Wang, QF Yang, QQ Guo, H Xiao, XX Jin, HJ Li, LL Zhang, TJ Wu, QB AF Wang, Qingfeng Yang, Qianqian Guo, Hong Xiao, Xiongxin Jin, Huijun Li, Lili Zhang, Tingjun Wu, Qingbai TI Hydrothermal variations in soils resulting from the freezing and thawing processes in the active layer of an alpine grassland in the Qilian Mountains, northeastern Tibetan Plateau SO THEORETICAL AND APPLIED CLIMATOLOGY DT Article AB Soil hydrothermal dynamics, resulting from the freezing and thawing processes in the active layer and their influencing factors, were studied in the upper Heihe River Basin (UHRB) in the Qilian Mountains, northeastern Tibetan Plateau. Soil temperature and water content measurements were taken in the active layer of the UHRB in alpine grassland from 2013 to 2014. The results showed that the thaw rate of the active layer was significantly smaller in alpine paludal meadows than the thaw rate in alpine meadows and alpine steppes. This was mainly related to the hydrothermal properties of soils in the active layer, such as moisture content, thermal conductivity, and specific heat. During the thawing process, the active layer soil water content was higher and fluctuated less in alpine paludal meadows. Conversely, the soil water content was lower and fluctuated more significantly in alpine meadows and alpine steppes. These findings could be explained by the prevalence of peat soils, with a low bulk density, and high clay and organic matter content. By contrast, the soil particles in the active layer of alpine meadows and alpine steppes were significantly coarser, with higher bulk density and lower organic matter content. During the freezing process, gravel content and soil texture had a great impact on the unfrozen water content in the frozen soils. However, the factors influencing the soil water retention in frozen soils are complex, and further study is needed. These results provide theoretical support for the evaluation of the hydrological characteristics of the alpine permafrost zone in the Qilian Mountains. Furthermore, the effect of frozen ground on hydrological changes due to climate change in the Heihe River Basin can be simulated and predicted, providing a scientific basis for the ecological conservation of the Qilian Mountains National Park. C1 [Wang, Qingfeng; Yang, Qianqian; Jin, Huijun; Wu, Qingbai] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. [Guo, Hong; Xiao, Xiongxin; Li, Lili; Zhang, Tingjun] Lanzhou Univ, Coll Earth & Environm Sci, Minist Educ, Key Lab Western Chinas Environm Syst, 222 South Tianshui Rd, Lanzhou 730000, Gansu, Peoples R China. [Jin, Huijun] Harbin Inst Technol, Sch Civil Engn, 73 Huanghe Rd, Harbin 150090, Heilongjiang, Peoples R China. RP Wang, QF (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. EM qf_w@lzb.ac.cn; yangqq2009@126.com TC 18 Z9 21 PD MAY PY 2019 VL 136 IS 3-4 BP 929 EP 941 DI 10.1007/s00704-018-2529-y UT WOS:000467151000010 DA 2023-03-23 ER PT J AU Yao, XX Wu, JP Gong, XY Lang, X Wang, CL Song, SZ Ahmad, AA AF Yao, Xixi Wu, Jianping Gong, Xuyin Lang, Xia Wang, Cailian Song, Shuzhen Ahmad, Anum Ali TI Effects of long term fencing on biomass, coverage, density, biodiversity and nutritional values of vegetation community in an alpine meadow of the Qinghai-Tibet Plateau SO ECOLOGICAL ENGINEERING DT Article AB Grazing is widely regarded as a critical factor affecting the vegetation community structure, productivity and nutritional value of natural grasslands. To protect and restore degraded grasslands, fencing is considered as a valuable tool. However, it is not clear whether long term fencing of grazers can improve the condition and nutritional values of vegetation community and soil properties. We have compared the impact of long term fencing and continuous grazing on vegetation community structure, nutritional values and soil properties of alpine meadow of the Qinghai-Tibet Plateau by field investigation (11-13 years) and indoor analysis during 2015-2017. Our results showed that long-term fencing clearly increased the above ground biomass and coverage of plant functional types. Long-term fencing improved the development of four plant functional types (GG, grass species group; SG, sedge species group; LG, leguminous species group and FG, forbs species group), but inhibited the growth of noxious species (NG). Long-term fencing significantly improved soil TN, TP, TK, AN, AP and AK in 0-10 cm soil layer, considerable effect on the improvement of soil TN, TP, AN, AP and AK in 10-20 cm soil layer and soil TP, AN, AP and AK in 20-30 cm soil layer were observed. However, long-term fencing significantly decreased biodiversity indicators i.e., Richness index, Shannon-Wiener diversity index and Evenness index of vegetation community. A substantial decrease in the density, biodiversity and nutritional values (CP, IVTD and NDF) of four edible plants functional types (GG, SG, LG and FG) were recorded. While a downward trend in the TN, AN, AP and AK of above ground biomass and soil were observed during 2015-2017 in alpine meadows due to long term grazing. The density, diversity and nutritional value (CP and IVTD) of long-term fencing alpine meadows showed a downward trend over time (2015-2017). By considering the biodiversity conservation and grassland livestock production, long-term fencing is not beneficial for the improvement of density, biodiversity and nutritional values of plant functional types. Thus, our study suggests that rotational fencing and grazing would be a good management strategy to restore and improve the biodiversity and nutritional values of plant functional types in natural grassland ecosystem. C1 [Yao, Xixi; Wu, Jianping] Gansu Agr Univ, Coll Anim Sci & Technol, 1 Yingmen Village Anning, Lanzhou 730070, Gansu, Peoples R China. [Wu, Jianping; Gong, Xuyin; Lang, Xia; Wang, Cailian; Song, Shuzhen] Gansu Acad Agr Sci, 1 Agr Acad Village Anning, Lanzhou 730070, Gansu, Peoples R China. [Ahmad, Anum Ali] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, 222 Tianshui South Rd, Lanzhou 730070, Gansu, Peoples R China. RP Wu, JP (通讯作者)，1 Agr Acad Village Anning, Lanzhou 730070, Gansu, Peoples R China. EM wujp@gsagr.ac.cn TC 35 Z9 42 PD MAY PY 2019 VL 130 BP 80 EP 93 DI 10.1016/j.ecoleng.2019.01.016 UT WOS:000463884100008 DA 2023-03-23 ER PT J AU Zhang, LY Adams, JM Dumont, MG Li, YT Shi, Y He, D He, JS Chu, HY AF Zhang, Liyan Adams, Jonathan M. Dumont, Marc G. Li, Yuntao Shi, Yu He, Dan He, Jin-Sheng Chu, Haiyan TI Distinct methanotrophic communities exist in habitats with different soil water contents SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB Aerobic methane oxidizing bacteria play a key role in controlling global climate by reducing methane (CH4) emissions in natural ecosystems. We studied the community assembly processes and co-occurrence interactions of soil methanotrophs in three habitats (an alpine meadow, a marsh meadow, and a marsh) from Qinghai-Tibetan Plateau. Methanotrophic communities and CH4 oxidation potentials varied considerably between the habitats, and the diversity of methanotrophs was significantly lower in marsh meadow than in the other two soils (P < 0.001). Methanotrophic bacterial diversity was significantly correlated with soil dissolved organic carbon (DOC), pH, total carbon (TC), and total nitrogen (TN), while methanotrophic community structure was mostly correlated with soil C/N, TC, soil moisture, and TN. Stochasticity dominated methanotrophic community assembly, and increased from 67.6% in the alpine meadow and 68.0% in the marsh meadow to 98.2% in the marsh. The natural connectivity of co-occurrence network was greater in the alpine meadow than in the other two habitats, suggesting a more stable network in the alpine meadow. Methanotroph diversity contributed to the sub-network topological differences and keystone species were identified such as USC gamma, Methylobacter, and RPC-1. The results suggest the existence of distinct community assembly processes and co-occurrence patterns of soil methanotrophs among different habitats, which may ultimately enhance the understanding of factors influencing CH4 oxidation rates. C1 [Zhang, Liyan; Li, Yuntao; Shi, Yu; Chu, Haiyan] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, 71 East Beijing Rd, Nanjing 210008, Jiangsu, Peoples R China. [Zhang, Liyan; Li, Yuntao; Chu, Haiyan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Adams, Jonathan M.] Seoul Natl Univ, Dept Biol Sci, Seoul, South Korea. [Dumont, Marc G.] Univ Southampton, Biol Sci, Southampton, Hants, England. [He, Dan] Chinese Acad Sci, South China Bot Garden, Ctr Ecol & Environm Sci, Guangzhou 510650, Guangdong, Peoples R China. [He, Jin-Sheng] Peking Univ, Minist Educ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. [He, Jin-Sheng] Peking Univ, Minist Educ, Key Lab Earth Surface Proc, Beijing 100871, Peoples R China. [He, Jin-Sheng] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [He, Jin-Sheng] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730000, Gansu, Peoples R China. RP Chu, HY (通讯作者)，Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, 71 East Beijing Rd, Nanjing 210008, Jiangsu, Peoples R China. EM hychu@issas.ac.cn TC 36 Z9 36 PD MAY PY 2019 VL 132 BP 143 EP 152 DI 10.1016/j.soilbio.2019.02.007 UT WOS:000465057200016 DA 2023-03-23 ER PT J AU Yan, Y Tian, LL Du, ZY Chang, SX Cai, YJ AF Yan, Yan Tian, Linlin Du, Ziyin Chang, Scott X. Cai, Yanjiang TI Carbon, nitrogen and phosphorus stocks differ among vegetation patch types in a degraded alpine steppe SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Purpose Degradation of grassland creates diverse vegetation patch types with plant species with different palatabilities, potentially affecting ecosystem productivity and soil organic carbon (SOC) sequestration. This study investigated variations in SOC densities and carbon/nitrogen/phosphorus (C/N/P) ratios among vegetation patch types in a degraded alpine steppe on the Qinghai-Tibetan Plateau. Materials and methods We examined soil, shoot and root C, N and P densities, and C/N/P ratios in a growing season for five vegetation patch types dominated by palatable plant species Stipa purpurea, S. purpurea and Poa litwinowiana, and unpalatable plant species Leontopodium nanum, Artemisia nanschanica, and Oxytropis glacialis. Results and discussion Soil C and N as well as shoot and root densities varied among patch types, but not soil C/N. Patches dominated by unpalatable plant species had a lower SOC density, lower soil and plant N/P ratios, and greater plant nutrient densities than those dominated by palatable plant species. Vegetation patch type strongly influenced nutrient densities and ratios in soil-plant systems, and sampling only areas dominated by palatable plant species may overestimate the C sequestration rate at the ecosystem scale. Conclusions Even though patch-level plant biomass and nutrient density may increase with increasing degradation, the decrease in palatability and SOC storage at the ecosystem scale would impair grassland sustainability as alpine grassland degradation proceeds. The palatability of plants should thus be considered for improving regional SOC stock estimate in future research. C1 [Yan, Yan; Tian, Linlin; Du, Ziyin; Cai, Yanjiang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China. [Chang, Scott X.] Univ Alberta, Dept Renewable Resources, 442 Earth Sci Bldg, Edmonton, AB T6G 2E3, Canada. [Cai, Yanjiang] Zhejiang A&F Univ, State Key Lab Subtrop Silviculture, Hangzhou 311300, Zhejiang, Peoples R China. RP Cai, YJ (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China.; Cai, YJ (通讯作者)，Zhejiang A&F Univ, State Key Lab Subtrop Silviculture, Hangzhou 311300, Zhejiang, Peoples R China. EM yjcai@zafu.edu.cn TC 9 Z9 10 PD APR PY 2019 VL 19 IS 4 BP 1809 EP 1819 DI 10.1007/s11368-018-2191-0 UT WOS:000462500000019 DA 2023-03-23 ER PT J AU Zhou, XL Liu, XD Zhang, PF Guo, Z Du, GZ AF Zhou, Xiaolong Liu, Xudong Zhang, Pengfei Guo, Zhi Du, Guozhen TI Increased community compositional dissimilarity alleviates species loss following nutrient enrichment at large spatial scales SO JOURNAL OF PLANT ECOLOGY DT Article AB Aims Anthropogenic activities have drastically increased nutrient availability, resulting in declines in species richness in many plant communities. However, most previous studies have explored only species-loss patterns and mechanisms over small sampling areas, so their results might overestimate species loss at larger spatial scales. The aim of this research was to explore species diversity change patterns and species-loss rates at multiple scales in alpine meadow communities following nutrient enrichment. Specifically, we asked two closely related questions: (i) do changes in species diversity and species-loss patterns differ among spatial scales? and (ii) how does community compositional dissimilarity and species turnover change among spatial scale? Methods This study was implemented in an alpine meadow community, which is regarded as one of the most sensitive and vulnerable terrestrial ecosystems to anthropogenic nutrient enrichment. We conducted a fertilization experiment that involved the addition of nitrogen (N), phosphorus (P) and a mixture of both to a series of quadrats ranging from 1 to 16 m(2) over 5 years to study the variations in the patterns of species diversity in response to nutrient additions at different spatial scales. Important Findings Our results showed that the changes in species diversity and species loss were dependent on the type of fertilization and the spatial scale. After N and NP fertilization, species diversity significantly decreased at the small scale but not at the large scale, and the rate of species loss decreased as the spatial scale increased. In contrast, the differences between the P addition and control communities were negligible at both the small and large spatial scales. N fertilization caused species to be lost from the small sampling scale, but because different species were lost from different samples, there was an increase in compositional dissimilarity at larger spatial scales, which reduced the total number of species lost when measured at larger scales. These findings highlight spatial scale in evaluating the biodiversity loss after fertilization and suggest that the compositional dissimilarity might play an important role in mediating species loss after fertilization. Our study significantly improved our understanding of changes in species diversity and species loss at different spatial scales under nutrient-enrichment scenarios. C1 [Zhou, Xiaolong] Xinjiang Univ, Inst Arid Ecol & Environm, Shengli Rd 666, Urumqi 830046, Xinjiang, Peoples R China. [Zhou, Xiaolong] Xinjiang Univ, Key Lab Oasis Ecol, Shengli Rd 666, Urumqi 830046, Xinjiang, Peoples R China. [Liu, Xudong; Zhang, Pengfei; Guo, Zhi; Du, Guozhen] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Southern Tianshui Rd 222, Lanzhou 730000, Gansu, Peoples R China. RP Zhou, XL (通讯作者)，Xinjiang Univ, Inst Arid Ecol & Environm, Shengli Rd 666, Urumqi 830046, Xinjiang, Peoples R China. EM zhouxl13@lzu.edu.cn TC 5 Z9 5 PD APR PY 2019 VL 12 IS 2 BP 376 EP 386 DI 10.1093/jpe/rty035 UT WOS:000461146600019 DA 2023-03-23 ER PT J AU Luo, WY Wang, ZY Shao, M Lu, JF Qian, GQ Dong, ZB Hesp, PA Bateman, MD AF Luo, Wanyin Wang, Zhongyuan Shao, Mei Lu, Junfeng Qian, Guangqiang Dong, Zhibao Hesp, Patrick A. Bateman, Mark D. TI Historical evolution and controls on mega-blowouts in northeastern Qinghai-Tibetan Plateau, China SO GEOMORPHOLOGY DT Article AB Mega-blowouts are very large-scale deflationary landforms, formed by wind erosion. They are abundant in the Gonghe basin, northeast margin of the Qinghai-Tibet Plateau (QTP) and little is known about the evolution, dynamics or controls on the mega-blowout development. Here we report on mega-blowouts' morphodynamic expansion rates based on 4 years of monitoring. Also presented is a remotely sensed longer-term (48 years) morphologic change record which is used to understand the initiation, growth and evolution of mega-blowouts in alpine grasslands. Links between the morphodynamics and blowout-controlling factors are analysed. The expansion rates of the monitored blowouts vary according to blowout area, with different parts of the blowouts expanding at different rates. Generally longitudinal (downwind) mega-blowout expansion is greatest, with upwind headwall expansion via collapse being particularly significant. The growth of depositional lobes downwind of mega-blowouts tends to be faster than growth of the deflation basins. Merging of adjacent blowouts is one of the key mechanisms for mega-blowout development and extension. Sediment characteristics, wind erosion, water erosion, and freeze-thaw processes also all play a part in mega-blowout initiation and expansion. However, the relative roles that these factors play may differ according to a blowout's evolutionary stage. Due to an almost unlimited depth of sand, very low water table, and short grass vegetation cover, evolution into parabolic dunes is limited. A large proportion of sand patches and small blowouts around the mega-blowouts are still developing in the Gonghe basin proving that land degradation is still ongoing. Future work will focus on the feedback mechanisms between the blowout morphodynamics, climate change and anthropogenic impacts. (C) 2019 Elsevier B.V. All rights reserved. C1 [Luo, Wanyin; Wang, Zhongyuan; Shao, Mei; Lu, Junfeng; Qian, Guangqiang; Dong, Zhibao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou 730000, Gansu, Peoples R China. [Luo, Wanyin; Bateman, Mark D.] Univ Sheffield, Geog Dept, Winter St, Sheffield S10 2TN, S Yorkshire, England. [Wang, Zhongyuan] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Dong, Zhibao] Shaanxi Normal Univ, Sch Geog & Tourism, Xian, Shaanxi, Peoples R China. [Hesp, Patrick A.] Flinders Univ S Australia, Coll Sci & Engn, Beach & Dune Syst BeaDS Lab, Sturt Rd, Adelaide, SA 5042, Australia. RP Luo, WY (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. EM wyluo@lzb.ac.cn TC 6 Z9 9 PD MAR 15 PY 2019 VL 329 BP 17 EP 31 DI 10.1016/j.geomorph.2018.12.033 UT WOS:000460085400002 DA 2023-03-23 ER PT J AU Tian, LM Zhao, L Wu, XD Hu, GJ Fang, HB Zhao, YH Sheng, Y Chen, J Wu, JC Li, WP Ping, CL Pang, QQ Liu, Y Shi, W Wu, TH Zhang, XM AF Tian, Liming Zhao, Lin Wu, Xiaodong Hu, Guojie Fang, Hongbing Zhao, Yonghua Sheng, Yu Chen, Ji Wu, Jichun Li, Wangping Ping, Chien-Lu Pang, Qiangqiang Liu, Yang Shi, Wei Wu, Tonghua Zhang, Xiumin TI Variations in soil nutrient availability across Tibetan grassland from the 1980s to 2010s SO GEODERMA DT Article AB Changes in soil nutrient availability attributed to climate change and associated permafrost degradation have been reported in several ecosystems. However, little is known about the changes of soil nutrient availability in alpine grassland ecosystems. Based on a comprehensive dataset and random forest models, we investigated soil available nutrients changes and their relationships with environmental factors for the top 10 cm soils across Tibetan grassland between the 1980s and 2010s. During this period, topsoil available nitrogen stocks increased significantly by 24%, while available phosphorus and potassium stocks decreased significantly by 3% and 23%, respectively. Topsoil nutrient availability dynamics varied substantially among vegetation types. Initial nutrient stocks explained the largest proportions of available nutrients changes, though climate, permafrost, vegetation, soil properties, and their interactions also had significant contributions. The increasing rate of active layer thickness was negatively related to soil available nitrogen dynamics but did not significantly change available phosphorus and potassium, indicating that the increase in the annual depth of surface thaw of the permafrost was associated with an increase in soil nitrogen availability but no significant changes in available phosphorus and potassium. These results suggest that the Tibetan alpine grassland ecosystems may shift from nitrogen limited to phosphorus or potassium-limited in the future. C1 [Tian, Liming; Zhao, Lin] Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing 210044, Jiangsu, Peoples R China. [Tian, Liming; Zhao, Lin; Wu, Xiaodong; Hu, Guojie; Zhao, Yonghua; Pang, Qiangqiang; Liu, Yang; Shi, Wei; Wu, Tonghua] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, Lanzhou 730000, Gansu, Peoples R China. [Tian, Liming] Sichuan Univ, Coll Life Sci, Key Lab Bioresource & Ecoenvironm, Minist Educ, Chengdu 610064, Sichuan, Peoples R China. [Zhao, Lin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Fang, Hongbing] Lanzhou Jiaotong Univ, Sch Environm & Municipal Engn, Lanzhou 730070, Gansu, Peoples R China. [Sheng, Yu; Chen, Ji; Wu, Jichun; Zhang, Xiumin] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Gansu, Peoples R China. [Li, Wangping] Lanzhou Univ Technol, Sch Civil Engn, Lanzhou 730050, Gansu, Peoples R China. [Ping, Chien-Lu] Univ Alaska Fairbanks, Palmer Res Ctr, Agr & Forestry Expt Stn, Palmer, AK 99645 USA. RP Zhao, L (通讯作者)，Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing 210044, Jiangsu, Peoples R China. EM lzhao@nuist.edu.cn TC 22 Z9 24 PD MAR 15 PY 2019 VL 338 BP 197 EP 205 DI 10.1016/j.geoderma.2018.12.009 UT WOS:000457657000021 DA 2023-03-23 ER PT J AU Zhao, YF Wang, X Ou, YS Jia, HX Li, J Shi, CM Liu, Y AF Zhao, Yunfei Wang, Xia Ou, Yansheng Jia, Haixia Li, Jia Shi, Changming Liu, Yang TI Variations in soil delta C-13 with alpine meadow degradation on the eastern Qinghai-Tibet Plateau SO GEODERMA DT Article AB The alpine swampy meadow is a unique meadow type on the eastern Tibetan Plateau and is undergoing degradation. However, little is known about the responses of soil delta C-13 to alpine meadow degradation. Monitoring the beta value, which is the slope of the linear regression relating soil delta C-13 to the logarithm of soil organic carbon (SOC) content, provides an approach to infer SOC dynamics. In this study, we investigated soil delta C-13 and SOC contents along a soil profile (0-50 cm), together with several soil physicochemical and biomass properties in a swampy meadow (SM), a grassland meadow (GM), and a degraded meadow (DM). Then, the variations in soil delta C-13 and beta values and the main factors affecting them were analyzed. The results showed that soil delta C-13 increased with soil depth, but SOC decreased. The soil delta C-13 in the surface layer (0-10 cm) was comparable between GM and DM but was significantly lower in SM, and soil moisture was the major factor influencing the surface soil delta(13) value. The three meadow types could be ranked, from highest beta value to lowest, as follows: GM > SM > DM. The soil C/N ratio and soil texture explained large proportions of the variations in beta value. Our results demonstrated that the degradation of alpine meadows affects biomass and soil physicochemical properties, leading to a reduction in C inputs and an accelerated rate of SOC decomposition, followed by a decrease in SOC content. Our findings also indicated that monitoring changes in soil delta C-13 is an effective method to evaluate the degradation of alpine meadows, but it should be used with caution. This study provides a more comprehensive understanding of soil delta C-13 and SOC dynamics with alpine meadow degradation. C1 [Zhao, Yunfei; Wang, Xia; Ou, Yansheng; Jia, Haixia; Li, Jia; Shi, Changming; Liu, Yang] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Gansu, Peoples R China. [Zhao, Yunfei; Wang, Xia; Ou, Yansheng; Jia, Haixia; Li, Jia; Shi, Changming; Liu, Yang] Lanzhou Univ, Key Lab Environm Pollut Predict & Control, Lanzhou 730000, Gansu, Peoples R China. [Zhao, Yunfei; Wang, Xia; Ou, Yansheng; Jia, Haixia; Li, Jia] Lanzhou Univ, MOE Key Lab Western Chinas Environm Syst, Lanzhou 730000, Gansu, Peoples R China. RP Wang, X (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Gansu, Peoples R China.; Wang, X (通讯作者)，Lanzhou Univ, Key Lab Environm Pollut Predict & Control, Lanzhou 730000, Gansu, Peoples R China. EM wangxia@lzu.edu.cn TC 22 Z9 27 PD MAR 15 PY 2019 VL 338 BP 178 EP 186 DI 10.1016/j.geoderma.2018.12.005 UT WOS:000457657000019 DA 2023-03-23 ER PT J AU Wang, SZ Fan, JW Li, YZ Huang, L AF Wang, Suizi Fan, Jiangwen Li, Yuzhe Huang, Lin TI Effects of Grazing Exclusion on Biomass Growth and Species Diversity among Various Grassland Types of the Tibetan Plateau SO SUSTAINABILITY DT Article AB Livestock grazing is an important determinant of species diversity and plant growth. Overgrazing is identified as one of the most important disturbances resulting in grassland degradation. Although many restoration practices have been implemented, grazing exclusion is one of the most effective methods to restore degraded grasslands. We explored the impact of five years of grazing exclusion on plant growth and species diversity in four types of grasslands: temperate steppe (TS), swamp meadow (SM), alpine steppe (AS), and alpine meadow (AM). Our results showed that grazing exclusion increased plant height, coverage, biomass, and species diversity in all four grasslands. The aboveground biomass in AM (180.8%), TS (117.3%), and SW (105.9%) increased significantly more than AS (10.1%). Grazing exclusion in AM had the greatest effect on proportion of palatable species, and the increase in palatable species in AM was higher than that of the other grassland types significantly. Species diversity increased significantly within the enclosure in SM (23.9%) and AM (20.8%). Our results indicate that grazing exclusion is an effective management strategy to restore degraded grasslands and it works best in alpine meadow. This study contributes to the growing theoretical basis for grassland management strategies and has a significant effect on sustainable development for grassland resources and pastoral areas. C1 [Wang, Suizi; Fan, Jiangwen; Li, Yuzhe; Huang, Lin] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Wang, Suizi] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. RP Li, YZ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM wangsz.16b@igsnrr.ac.cn; fanjw@igsnrr.ac.cn; liyuzhe@igsnrr.ac.cn; huanglin@igsnrr.ac.cn TC 21 Z9 22 PD MAR 2 PY 2019 VL 11 IS 6 AR 1705 DI 10.3390/su11061705 UT WOS:000465613000137 DA 2023-03-23 ER PT J AU Hu, GJ Zhao, L Li, R Wu, XD Wu, TH Xie, CW Zhu, XF Su, YQ AF Hu, Guojie Zhao, Lin Li, Ren Wu, Xiaodong Wu, Tonghua Xie, Changwei Zhu, Xiaofan Su, Youqi TI Variations in soil temperature from 1980 to 2015 in permafrost regions on the Qinghai-Tibetan Plateau based on observed and reanalysis products SO GEODERMA DT Article AB Soil temperature is an important physical variable of soil and plays a key role in controlling the underground hydro-thermal processes in permafrost regions on the Qinghai-Tibetan Plateau (QTP). Daily soil temperatures were observed at five different vegetation cover sites (alpine wet meadow, alpine meadow, alpine steppe, alpine desert steppe and alpine desert) from 2012 to 2015 in permafrost regions on the QTP. The performance of three reanalysis soil temperature products (National Centers for Environmental Prediction Climate Forecast System and Climate Forecast System Reanalysis (CFSR), European Centre for Medium-Range Weather Forecasts interim reanalysis (ERA-Interim), and Global Land Data Assimilation System (GLDAS-NOAH)) at four depths (0-10, 10-40, 40-100 and 100-200 cm) was evaluated using the observation data. The results revealed that the CFSR soil temperature products had the best performance at most sites and that GLDAS-NOAH and Era-Interim had the poorest performance. However, the original CFSR soil temperature products underestimated the lowest temperatures. The calibration models for CFSR soil temperature products were established using the observed daily soil temperature from 2013 to 2015 and were validated with observed data from 2012. The results showed that the calibrated CFSv2 products were closer to the observations at different depths in the study sites. Moreover, we investigated the variations of seasonal and annual mean soil temperature from 1980 to 2015 at depths of 0-10, 10-40, 40-100 and 100-200 cm using the soil temperature calibration results. It was found that the soil temperatures at different depths all warmed fastest in spring, more slowly in winter and slowest in autumn at most sites. In addition, the average annual soil temperature exhibited significant warming trends in the permafrost regions on the QTP. The effect was largest with alpine desert steppe and smallest with alpine wet meadow, with statistically significant rates of 0.0599, 0.0468, 0.0438, 0.0282 and 0.0145 degrees C/year in alpine desert steppe, alpine desert, alpine steppe, alpine meadow and alpine wet meadow, respectively. This research provides a foundation for understanding the thermal properties of permafrost on the Qinghai-Tibetan Plateau under climate change. C1 [Hu, Guojie; Li, Ren; Wu, Xiaodong; Wu, Tonghua; Xie, Changwei; Zhu, Xiaofan] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Xizang Plateau, Lanzhou 730000, Gansu, Peoples R China. [Zhao, Lin] Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing 210000, Jiangsu, Peoples R China. [Su, Youqi] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Land Surface Proc & Climate Change Cold &, Lanzhou 730000, Gansu, Peoples R China. [Zhu, Xiaofan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Zhao, L (通讯作者)，Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing 210000, Jiangsu, Peoples R China. EM huguojie123@126.com; linzhao@lzb.ac.cn TC 68 Z9 79 PD MAR 1 PY 2019 VL 337 BP 893 EP 905 DI 10.1016/j.geoderma.2018.10.044 UT WOS:000456761500088 DA 2023-03-23 ER PT J AU Lin, F Liu, CY Hu, XX Fu, YF Zheng, XH Wang, R Zhang, W Cao, GM AF Lin, Fei Liu, Chunyan Hu, Xiaoxia Fu, Yongfeng Zheng, Xunhua Wang, Rui Zhang, Wei Cao, Guangmin TI Characterizing nitric oxide emissions from two typical alpine ecosystems SO JOURNAL OF ENVIRONMENTAL SCIENCES DT Article AB A portion of alpine meadows has been and will continue to be cultivated due to the concurrent increasing demands for animal- and crop-oriented foods and global warming. However, it remains unclear how these long-term changes in land use will affect nitric oxide (NO) emission. At a field site with a calcareous soil on the Qinghai-Tibetan Plateau, the authors measured the year-round NO fluxes and related variables in a typically winter-grazed natural alpine meadow (NAM) and its adjacent forage oat field (FOF). The results showed that long-term plow tillage, fertilization and growing forage oats significantly yielded ca. 2.7 times more (p < 0.01) NO emissions from the FOF than the NAM (conservatively 208 vs. 56 g N/(ha.year) on average). The spring freeze-thaw period and non-growing season accounted for 17%-35% of the annual emissions, respectively. The Qio of surface soil temperature (T-s) was 8.9 in the NAM (vs. 3.8 in the FOF), indicating increases of 24%-93% in NO emissions per 1-3 degrees C increase. However, the warming-induced increases could be smaller than those due to land use change and management practices. The T-s and concentrations of ammonium, nitrate and water-extractable organic carbon jointly explained 69% of the variance in daily NO fluxes from both fields during the annual period (p < 0.001). This result indicates that temporally and/or spatially distributed NO fluxes from landscapes with calcareous soils across native alpine meadows and/or fields cultivated with forage oats can be predicted by simultaneous observations of these four soil variables. (C) 2018 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. C1 [Lin, Fei; Liu, Chunyan; Hu, Xiaoxia; Fu, Yongfeng; Zheng, Xunhua; Wang, Rui; Zhang, Wei] Chinese Acad Sci, State Key Lab Atmospher Boundary Layer Phys & Atm, Inst Atmospher Phys, Beijing 100029, Peoples R China. [Lin, Fei; Hu, Xiaoxia; Fu, Yongfeng; Zheng, Xunhua] Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Beijing 100049, Peoples R China. [Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Qinghai, Peoples R China. RP Zheng, XH (通讯作者)，Chinese Acad Sci, State Key Lab Atmospher Boundary Layer Phys & Atm, Inst Atmospher Phys, Beijing 100029, Peoples R China.; Zheng, XH (通讯作者)，Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Beijing 100049, Peoples R China. EM xunhua.zheng@post.iap.ac.cn TC 0 Z9 0 PD MAR PY 2019 VL 77 BP 312 EP 322 DI 10.1016/j.jes.2018.08.011 UT WOS:000463374900030 DA 2023-03-23 ER PT J AU Sun, XL Li, M Wang, GX Drosos, M Liu, FL Hu, ZY AF Sun, Xiaolei Li, Meng Wang, Guoxi Drosos, Marios Liu, Fulai Hu, Zhengyi TI Response of phosphorus fractions to land-use change followed by long-term fertilization in a sub-alpine humid soil of Qinghai-Tibet plateau SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB PurposeIdentification of phosphorus (P) species is essential to understand the transformation and availability of P in soil. However, P species as affected by land use change along with fertilization has received little attention in a sub-alpine humid soil of Tibet plateau.Materials and methodsIn this study, we investigated the changes in P species using Hedley sequential fractionation and liquid-state P-31-NMR spectroscopy in soils under meadow (M) and under cropland with (CF) or without (CNF) long-term fertilization for 26years in a sub-alpine cold-humid region in Qinghai-Tibet plateau.Results and discussionLand-use change and long-term fertilization affected the status and fractions of P. A strong mineralization of organic P (OP) was induced by losing protection of soil organic matter (SOM) and Fe and Al oxides during land-use change and resulted in an increase of orthophosphate (from 56.49mgkg(-1) in M soils to 130.07mgkg(-1) in CNF soils) and great decreases of orthophosphate diesters (diester-P, from 23.35mgkg(-1) in M soils to 10.68mgkg(-1) in CNF soils) and monoesters (from 336.04mgkg(-1) in M soils to 73.26mgkg(-1) in CNF soils). Long-term fertilization boosted P supply but failed to reclaim soil diester-P (from 10.68mgkg(-1) in CNF soils to 7.79mgkg(-1) in CF soils). This may be due to the fragile protection from the combination of SOM with diester-P when long-term fertilization had only improved SOM in a slight extent.ConclusionsThese results suggest that SOM plays an important role in the soil P cycling and prevents OP mineralization and losses from soil. It is recommended that optimization of soil nutrient management integrated with SOM was required to improve the P use efficiency for the development of sustainable agriculture. C1 [Sun, Xiaolei; Wang, Guoxi; Hu, Zhengyi] Univ Chinese Acad Sci, Coll Resources & Environm, Sino Danish Coll, Beijing 100049, Peoples R China. [Sun, Xiaolei; Li, Meng; Wang, Guoxi; Liu, Fulai; Hu, Zhengyi] Sino Danish Ctr Educ & Res, Beijing 100190, Peoples R China. [Sun, Xiaolei; Li, Meng; Liu, Fulai] Univ Copenhagen, Crop Sci Sect, Dept Plant & Environm Sci, Hojbakkegaard Alle 13, DK-2630 Taastrup, Denmark. [Li, Meng] Chinese Res Inst Environm Sci, State Key Lab Environm Criteria & Risk Assessment, Beijing 100012, Peoples R China. [Drosos, Marios] Univ Napoli BFederico II, Ctr Interdipartimentale Ric Risonanza Magnet Nucl, Via Univ 100, I-80055 Portici, Italy. RP Hu, ZY (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Sino Danish Coll, Beijing 100049, Peoples R China.; Li, M; Hu, ZY (通讯作者)，Sino Danish Ctr Educ & Res, Beijing 100190, Peoples R China.; Li, M (通讯作者)，Univ Copenhagen, Crop Sci Sect, Dept Plant & Environm Sci, Hojbakkegaard Alle 13, DK-2630 Taastrup, Denmark. EM limeng12b@mails.ucas.ac.cn; zhyhu@ucas.ac.cn TC 6 Z9 6 PD MAR PY 2019 VL 19 IS 3 BP 1109 EP 1119 DI 10.1007/s11368-018-2132-y UT WOS:000459805400006 DA 2023-03-23 ER PT J AU Wei, HX Zhao, JX Luo, TX AF Wei, Haixia Zhao, Jingxue Luo, Tianxiang TI The effect of pika grazing on Stipa purpurea is amplified by warming but alleviated by increased precipitation in an alpine grassland SO PLANT ECOLOGY DT Article AB Climate warming may cause alpine grassland degradation by decreasing plant growth and increasing pika grazing, although the concurrent precipitation change may further confound the plant and pika responses to warming. We aim to investigate the interactive effect of changes in temperature, precipitation and pika herbivory on plant growth. A 2-year field manipulation experiment of 2 degrees C warming and 15-30% increased precipitation was conducted in an alpine grassland ecosystem. During the growing season, warming significantly reduced plant height growth of the two dominant species Stipa purpurea and Kobresia macrantha, whereas increased precipitation and its interactions with warming stimulated plant height growth. Regarding the widespread species S. purpurea, warming significantly increased the frequency, consumption, and intensity of pika herbivory, whereas increased precipitation significantly reduced pika herbivory intensity, resulting in a net positive effect of increased precipitation and its interactions with warming and pika herbivory on plant growth. However, the pika grazing on K. macrantha varied little with warming and precipitation change. There was generally a much larger effect of pika grazing on S. Purpurea than on K. macrantha, which corresponded to higher specific leaf area and nitrogen content in S. purpurea than in K. macrantha. The diet selection of pika may explain why the sensitivity of pika herbivory to warming and precipitation change differed between the two dominant plant species. Our data suggest that the effect of pika grazing on Stipa plants is amplified by climatic warming, and such a negative effect could be alleviated by increased precipitation. C1 [Wei, Haixia; Zhao, Jingxue; Luo, Tianxiang] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Courtyard 16,Bldg 3,Lincui Rd, Beijing 100101, Peoples R China. [Wei, Haixia] Zaozhuang Univ, Coll Tourism & Resource Environm, Zaozhuang 277160, Shandong, Peoples R China. [Luo, Tianxiang] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. RP Luo, TX (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Courtyard 16,Bldg 3,Lincui Rd, Beijing 100101, Peoples R China. EM luotx@itpcas.ac.cn TC 9 Z9 9 PD MAR PY 2019 VL 220 IS 3 BP 371 EP 381 DI 10.1007/s11258-019-00920-5 UT WOS:000461204000007 DA 2023-03-23 ER PT J AU Yao, XX Wu, JP Gong, XY Lang, X Wang, CL AF Yao, Xixi Wu, Jianping Gong, Xuyin Lang, Xia Wang, Cailian TI Grazing exclosures solely are not the best methods for sustaining alpine grasslands SO PEERJ DT Article AB Background. Grazing is widely regarded as a critical factor affecting the vegetation structure, productivity and nutritional value of natural grasslands. To protect and restore degraded grasslands, non-grazed exclosures are considered as a valuable tool. However, it is not clear whether long term non-grazed exclosures of grazers can improve the condition and nutritional value of vegetation and soil properties. Methods. We have compared the impact of long-term non-grazed and continuous grazed management strategy on vegetation structure, nutritional values and soil properties of alpine meadow of the Qinghai-Tibet Plateau by field investigation (11-13 years) and indoor analysis during 2015-2017. Results. Our results showed that long-term non-grazed exclosures clearly increased the aboveground biomass and coverage of plant functional types. Long-term non-grazed exclosures improved the development of all vegetation types, except NG (GG, grass species type; SG, sedge species type; LG, leguminous species type; FG, forbs species type and NG, noxious species type). Long-term non-grazed exclosures significantly improved all six measured soil properties (TN, total nitrogen; TP, total phosphorus; TK, total potassium; AN, available nitrogen; AP, available phosphorus and AK, available potassium) in 0-10 cm soil layer, considerable effect on the improvement of all measured soil properties, except TK in 10-20 cm soil layer and all measured soil properties, except TN and TK in 20-30 cm soil layer were observed. However, long-term non-grazed exclosures significantly decreased biodiversity indicators i.e., species richness, Shannon diversity index and Evenness index of vegetation. A substantial decrease in the density, biodiversity and nutritional values (CP (crude protein), IVTD (in vitro ture digestibility) and NDF (neutral detergent fiber)) of all vegetation types, except NG were recorded. While a downward trend in aboveground biomass and all measured soil properties except TP and TK were observed during 2015-2017 in alpine meadows due to long-term grazed treatment. The density, diversity and nutritional value (CP and IVTD) of long-term non-grazed alpine meadows showed a downward trend over time (2015-2017). By considering the biodiversity conservation and grassland livestock production, long-term non-grazed exclosures are not beneficial for the improvement of density, biodiversity and nutritional values of plant functional types. Thus, our study suggests that rotational non-grazed and grazed treatment would be a good management strategy to restore and improve the biodiversity and nutritional values of plant functional types in natural grassland ecosystems. C1 [Yao, Xixi; Wu, Jianping] Gansu Agr Univ, Coll Anim Sci & Technol, Lanzhou, Gansu, Peoples R China. [Wu, Jianping; Gong, Xuyin; Lang, Xia; Wang, Cailian] Gansu Acad Agr Sci, Lanzhou, Gansu, Peoples R China. RP Wu, JP (通讯作者)，Gansu Agr Univ, Coll Anim Sci & Technol, Lanzhou, Gansu, Peoples R China.; Wu, JP (通讯作者)，Gansu Acad Agr Sci, Lanzhou, Gansu, Peoples R China. EM 18993075304@163.com TC 8 Z9 9 PD FEB 22 PY 2019 VL 7 AR e6462 DI 10.7717/peerj.6462 UT WOS:000459409300003 DA 2023-03-23 ER PT J AU Zhou, H Zhang, DG Jiang, ZH Sun, P Xiao, HL Wu, YX Chen, JG AF Zhou, Heng Zhang, Degang Jiang, Zhehao Sun, Peng Xiao, Hailong Wu Yuxin Chen, Jiangang TI Changes in the soil microbial communities of alpine steppe at Qinghai-Tibetan Plateau under different degradation levels SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The alpine steppe at Qinghai-Tibetan Plateau is an important area for conservingwater source and grassland productivity; however, knowledge about the microbial community structure and function and the risk to human health due to alpine plant-soil ecosystems is limited. Thus, we used prediction methods, such as Tax4Fun, and performed a metagenome pre-study using 16S rRNA sequencing reads for a small scale survey of the microbial communities at degraded alpine steppes (i.e., non-degraded (ND), lightly degraded (LD), moderately degraded (MD), heavily degraded (HD), and extremely degraded (ED) steppes) by Illumina high-throughput sequencing technology. Although there were no significant differences in the microbial alpha diversity among the different degraded alpine steppes and the dominant phyla at the different degraded alpine steppes, including Actinobacteria, Proteobacterial, Acidobacteria and Chloroflexi, were similar, the beta-diversity significantly differed, indicating that alpine steppe degradation might result in variation in microbial community compositions. The linear discriminate analysis (LDA) effect size (LEfSe) analysis found twenty-one biomarkers, most of which belonged to Actinobacteria, suggesting that microbes with a special function (such as the decomposition soil organic matter) might survive in alpine steppes. In addition, the functional profiles of the bacterial populations revealed an association with many human diseases, including infectious diseases. In addition, the microbial communities were mainly correlated with the populations of Gramineae and soil total phosphorous. These results suggested that alpine steppe degradation could result in variations in the microbial community composition, structure and function at Qinghai-Tibetan Plateau. Further studies investigating the degraded alpine steppe environment are needed to isolate these potential pathogenic microbes and help protect livestock using these alpine steppes. (C) 2018 Elsevier B.V. All rights reserved. C1 [Zhou, Heng; Zhang, Degang; Jiang, Zhehao; Sun, Peng; Xiao, Hailong; Wu Yuxin; Chen, Jiangang] Gansu Agr Univ, Coll Grassland Sci, Lanzhou, Gansu, Peoples R China. [Jiang, Zhehao; Sun, Peng; Xiao, Hailong; Wu Yuxin; Chen, Jiangang] Gansu Agr Univ, Key Lab Grassland Ecosyst, Lanzhou, Gansu, Peoples R China. [Jiang, Zhehao; Sun, Peng; Xiao, Hailong; Wu Yuxin; Chen, Jiangang] US Ctr Grazing Land Ecosyst Sustainabil, Minist Educ Sino, Lanzhou, Gansu, Peoples R China. RP Zhou, H; Zhang, DG (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Lanzhou, Gansu, Peoples R China. EM hinychow@163.com; zhangdg@gsau.edu.cn TC 92 Z9 106 PD FEB 15 PY 2019 VL 651 BP 2281 EP 2291 DI 10.1016/j.scitotenv.2018.09.336 PN 2 UT WOS:000450551600060 DA 2023-03-23 ER PT J AU Zhu, XC Cao, RX Shao, MA AF Zhu, Xu-Chao Cao, Rui-Xue Shao, Ming-An TI Spatial simulation of soil-water content in dry and wet conditions in a hectometer-scale degraded alpine meadow SO LAND DEGRADATION & DEVELOPMENT DT Article AB Soil-water content (SWC) is a key factor in restoring degraded vegetation in alpine meadow ecosystems, but it has rarely been spatially simulated on a hectometer scale. We simulated SWC for typical dry and wet days in an alpine meadow using multivariate linear regression and autoregressive state-space equations based on SWC and other soil, terrain, and vegetation parameters to evaluate the efficiency of these two methods in dry and wet soil-moisture conditions. SWC measured on a typical dry day (SWC-D) and a wet day (SWC-W) increased and decreased with depth, respectively, and SWC-D was similar to SWC-W at a depth of 50 cm. Both SWC-D and SWC-W were significantly correlated with soil bulk density (BD), capillary porosity, silt content (Silt), gravel and stone content (GSC), pH, and organic carbon density (OCD), and both SWC-D and SWC-W were significantly auto-correlated and cross-correlated with BD, Silt, GSC, pH, and OCD at more than one lag distance. Multivariate linear regression using three variables in both dry and wet conditions had the highest accuracy, and the accuracy was generally higher for dry conditions than it was for wet conditions. The bivariate state-space model was the most accurate for both dry and wet soil conditions, but the expression variables were totally different, with pH and OCD for dry day and BD and Silt for wet day. The conditions of soil moisture should thus be considered when choosing variables with which to simulate SWC, instead of only considering the relationships between SWC and other variables. C1 [Zhu, Xu-Chao; Cao, Rui-Xue; Shao, Ming-An] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, 11A,Datun Rd, Beijing 100101, Peoples R China. [Zhu, Xu-Chao] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Jiangsu, Peoples R China. [Cao, Rui-Xue; Shao, Ming-An] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. RP Shao, MA (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, 11A,Datun Rd, Beijing 100101, Peoples R China. EM shaoma@igsnrr.ac.cn TC 9 Z9 9 PD FEB 15 PY 2019 VL 30 IS 3 BP 278 EP 289 DI 10.1002/ldr.3222 UT WOS:000457471200004 DA 2023-03-23 ER PT J AU Luo, RY Fan, JL Wang, WJ Luo, JF Kuzyakov, Y He, JS Chu, HY Ding, WX AF Luo, Ruyi Fan, Jianling Wang, Weijin Luo, Jiafa Kuzyakov, Yakov He, Jin-Sheng Chu, Haiyan Ding, Weixin TI Nitrogen and phosphorus enrichment accelerates soil organic carbon loss in alpine grassland on the Qinghai-Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Anthropogenic activities have substantially increased soil nutrient availability, which in turn affects ecosystem processes and functions, especially in nutrient-limited ecosystems such as alpine grasslands. Although considerable efforts have been devoted to understanding the responses of plant productivity and community composition to nitrogen (N) and phosphorus (P) enrichment, the nutrient enrichment effects on soil organic carbon (SOC) and microbial functions are not well understood. A four-year field experiment was established to evaluate the influence of continuous N and P enrichment on plant growth and SOC content in an alpine grassland of the Qinghai-Tibetan Plateau. The study included four treatments: Control without addition, N addition, P addition, and N plus P addition. N addition strongly increased aboveground plant biomass and decreased species richness by promoting growth of the dominant grasses species. In contrast, N and P enrichment significantly decreased SOC, especially the recalcitrant organic C content in the surface layer (0-10 cm) by reducing the slow C pool and enlarging the active C pool. Microbial biomass and activities of C-degrading enzymes (beta-glucosidase, cellulase and polyphenol oxidase) and an N-degrading enzyme (chitinase) increased with nutrient inputs. The CO2 emissions during a 300 d incubation period were positively correlated with the cellulase and chitinase activities, while the slow C pool was negatively correlated with the cellulase and polyphenol oxidase activities. Consequently, N and P enrichment accelerated decomposition of the recalcitrant C by stimulating microbial growth and increasing enzyme activities, leading to negative impacts on soil C sequestration. Overall, the results indicate that alpine grassland soils of the Qinghai-Tibetan Plateau may be changing from a C sink to a C source under increasing N and P availability, and improvement of alpine grassland management through nutrient inputs should consider not only the aboveground biomass for grazing, but also the soil C sequestration and ecosystem functioning. (c) 2018 Elsevier B.V. All rights reserved. C1 [Luo, Ruyi; Fan, Jianling; Chu, Haiyan; Ding, Weixin] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Jiangsu, Peoples R China. [Luo, Ruyi] Univ Chinese Acad Sci, Beijing 10049, Peoples R China. [Wang, Weijin] Dept Environm & Sci, Dutton Pk, Qld 4102, Australia. [Wang, Weijin] Griffith Univ, Environm Futures Res Inst, Nathan, Qld 4111, Australia. [Luo, Jiafa] AgResearch Ltd, Ruakura Res Ctr, Hamilton 3240, New Zealand. [Kuzyakov, Yakov] RUDN Univ, Agrotechnol Inst, Moscow, Russia. [Kuzyakov, Yakov] Univ Gottingen, Dept Agr Soil Sci, Dept Soil Sci Temperate Ecosyst, Busgenweg 2, D-37077 Gottingen, Germany. [Kuzyakov, Yakov] Soil Sci Consulting, D-37077 Gottingen, Germany. [He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. RP Ding, WX (通讯作者)，Chinese Acad Sci, Inst Soil Sci, Nanjing 210008, Jiangsu, Peoples R China. EM wxding@issas.ac.cn TC 57 Z9 63 PD FEB 10 PY 2019 VL 650 BP 303 EP 312 DI 10.1016/j.scitotenv.2018.09.038 PN 1 UT WOS:000447092700034 DA 2023-03-23 ER PT J AU Duan, M Li, AD Wu, YH Zhao, ZP Peng, CH DeLuca, TH Sun, SQ AF Duan, Min Li, Andi Wu, Yanhong Zhao, Zuoping Peng, Changhui DeLuca, Thomas H. Sun, Shouqin TI Differences of soil CO2 flux in two contrasting subalpine ecosystems on the eastern edge of the Qinghai-Tibetan Plateau: A four-year study SO ATMOSPHERIC ENVIRONMENT DT Article AB Alpine and subalpine ecosystems on Qinghai-Tibetan Plateau are rich in soil organic carbon and are among the most sensitive regions to climate change, while little is known about the dynamics of soil carbon dioxide (CO2 ) in alpine/subalpine ecosystems except for the grassland on the plateau. In this study, the monthly and inter-annual variations in soil CO2 emission from a subalpine coniferous forest and a subalpine shrubland ecosystem on the eastern edge of the Qinghai-Tibetan Plateau were investigated from 2012 to 2015 using the opaque steady-state chamber method. Soil CO2 flux rate during the growing season ranged from 153.3 to 683.6 mg m(- 2) h(-1) in the coniferous forest, being twice of that (76.6-347.3 mg m(-2) h(-1)) in the shrubland, due to the elevation-induced differences in soil temperature and water content and the vegetation-induced differences in soil carbon and nitrogen pools. Both ecosystems showed large monthly variations in soil CO2 flux rate, while relative to the coniferous forest, the shrubland had a less inter-annual variation in soil CO2 emission. The two ecosystems had the same temperature sensitivity of soil CO2 emission, which suggests that they will respond similarly to global warming concerning soil CO2 flux rate. The results highlight the importance of soil CO2 emission in subalpine forest and shrubland ecosystems, which can be helpful to reduce the uncertainty of regional estimates of carbon budget in subalpine regions under global warming. C1 [Duan, Min; Peng, Changhui] Northwest A&F Univ, Coll Forestry, Ctr Ecol Forecasting & Global Change, Yangling 712100, Shaanxi, Peoples R China. [Li, Andi; Wu, Yanhong; Sun, Shouqin] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Processes & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China. [Zhao, Zuoping] Shaanxi Univ Technol, Coll Chem & Environm Sci, Hanzhong 723000, Peoples R China. [DeLuca, Thomas H.] Univ Montana, Coll Forestry & Conservat, Missoula, MT 59812 USA. RP Sun, SQ (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Processes & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China. EM shouqinsun@imde.ac.cn TC 7 Z9 10 PD FEB 1 PY 2019 VL 198 BP 166 EP 174 DI 10.1016/j.atmosenv.2018.10.067 UT WOS:000455693900016 DA 2023-03-23 ER PT J AU Li, M Wu, JS Song, CQ He, YT Niu, B Fu, G Tarolli, P Tietjen, B Zhang, XZ AF Li, Meng Wu, Jianshuang Song, Chunqiao He, Yongtao Niu, Ben Fu, Gang Tarolli, Paolo Tietjen, Britta Zhang, Xianzhou TI Temporal Variability of Precipitation and Biomass of Alpine Grasslands on the Northern Tibetan Plateau SO REMOTE SENSING DT Article AB The timing regimes of precipitation can exert profound impacts on grassland ecosystems. However, it is still unclear how the peak aboveground biomass (AGB(peak)) of alpine grasslands responds to the temporal variability of growing season precipitation (GSP) on the northern Tibetan Plateau. Here, the temporal variability of precipitation was defined as the number and intensity of precipitation events as well as the time interval between consecutive precipitation events. We conducted annual field measurements of AGB(peak) between 2009 and 2016 at four sites that were representative of alpine meadow, meadow-steppe, alpine steppe, and desert-steppe. Thus, an empirical model was established with the time series of the field-measured AGB(peak) and the corresponding enhanced vegetation index (EVI) (R-2 = 0.78), which was used to estimate grassland AGB(peak) at the regional scale. The relative importance of the three indices of the temporal variability of precipitation, events, intensity, and time interval on grassland AGB(peak) was quantified by principal component regression and shown in a red-green-blue (RGB) composition map. The standardized importance values were used to calculate the vegetation sensitivity index to the temporal variability of precipitation (VSIP). Our results showed that the standardized VSIP was larger than 60 for only 15% of alpine grassland pixels and that AGB(peak) did not change significantly for more than 60% of alpine grassland pixels over the past decades, which was likely due to the nonsignificant changes in the temporal variability of precipitation in most pixels. However, a U-shaped relationship was found between VSIP and GSP across the four representative grassland types, indicating that the sensitivity of grassland AGB(peak) to precipitation was dependent on the types of grassland communities. Moreover, we found that the temporal variability of precipitation explained more of the field-measured AGB(peak) variance than did the total amount of precipitation alone at the site scale, which implies that the mechanisms underlying how the temporal variability of precipitation controls the AGB(peak) of alpine grasslands should be better understood at the local scale. We hypothesize that alpine grassland plants promptly respond to the temporal variability of precipitation to keep community biomass production more stable over time, but this conclusion should be further tested. Finally, we call for a long-term experimental study that includes multiple natural and anthropogenic factors together, such as warming, nitrogen deposition, and grazing and fencing, to better understand the mechanisms of alpine grassland stability on the Tibetan Plateau. C1 [Li, Meng; Wu, Jianshuang; He, Yongtao; Niu, Ben; Fu, Gang; Zhang, Xianzhou] Chinese Acad Sci, Lhasa Natl Ecol Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Li, Meng] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wu, Jianshuang; Tietjen, Britta] Free Univ Berlin, Inst Biol, Biodivers Theoret Ecol, D-14195 Berlin, Germany. [Song, Chunqiao] Chinese Acad Sci, Nanjing Inst Geog & Limnol, Key Lab Watershed Geog Sci, Nanjing 210008, Jiangsu, Peoples R China. [Tarolli, Paolo] Univ Padua, Dept Land Environm Agr & Forestry, I-35020 Legnaro, PD, Italy. [Tietjen, Britta] Berlin Brandenburg Inst Adv Biodivers Res BBIB, D-14195 Berlin, Germany. RP Wu, JS (通讯作者)，Chinese Acad Sci, Lhasa Natl Ecol Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China.; Wu, JS (通讯作者)，Free Univ Berlin, Inst Biol, Biodivers Theoret Ecol, D-14195 Berlin, Germany. EM lim.17b@igsnrr.ac.cn; wujs.07s@igsnrr.ac.cn; cqsong@niglas.ac.cn; heyt@igsnrr.ac.cn; niub@igsnrr.ac.cn; fugang@igsnrr.ac.cn; paolo.tarolli@unipd.it; britta.tietjen@fu-berlin.de; zhangxz@igsnrr.ac.cn TC 26 Z9 27 PD FEB 1 PY 2019 VL 11 IS 3 AR 360 DI 10.3390/rs11030360 UT WOS:000459944400148 DA 2023-03-23 ER PT J AU Ma, T Dai, GH Zhu, SS Chen, DM Chen, LT Lu, XT Wang, XB Zhu, JT Zhang, YJ Ma, WH He, JS Bai, YF Han, XG Feng, XJ AF Ma, Tian Dai, Guohua Zhu, Shanshan Chen, Dima Chen, Litong Lu, Xiaotao Wang, Xiaobo Zhu, Juntao Zhang, Yangjian Ma, Wenhong He, Jin-Sheng Bai, Yongfei Han, Xingguo Feng, Xiaojuan TI Distribution and Preservation of Root- and Shoot-Derived Carbon Components in Soils Across the Chinese-Mongolian Grasslands SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES DT Article AB The relative contribution of roots versus shoots to soil organic carbon (SOC) is a long-debated topic related to soil carbon formation and dynamics. However, the variation of root- and shoot-derived carbon in natural soils remains poorly constrained due to limited tools to separate them. Here we overcome the difficulty by analyzing biomarkers for root (suberin) and shoot (cutin) in grassland soils spanning >7,000km on the Qinghai-Tibetan and Mongolian Plateaus. Coupled with a comprehensive list of climatic, edaphic, and vegetation variables, we assess their inputs, distribution, and preservation patterns. We find that while suberin was a root-specific tracer, cutin biomarkers that occurred only in trace amount in roots also had a minor but nonnegligible contribution from belowground sources due to the massive root mass in the alpine grasslands. Both components had higher SOC-normalized concentrations in the alpine than temperate grasslands, along with a higher preservation percentage against net primary productivity and a lower degradation parameter, suggesting a better preservation of these plant-derived lipid components in the alpine region. Moreover, while cutin and suberin abundances were affected by plant inputs and other SOC constituents, the root mass normalized incorporation efficiency of suberin was only positively correlated to SOC in both regions with a steeper slope in the alpine grasslands and also negatively correlated to root mass in the alpine soils. These results imply that root carbon incorporation is sensitive to environmental variations in the cold region, suggesting potentially more dynamic alterations to root carbon sequestration with environmental changes. C1 [Ma, Tian; Dai, Guohua; Zhu, Shanshan; Chen, Dima; Bai, Yongfei; Han, Xingguo; Feng, Xiaojuan] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. [Ma, Tian; Zhu, Shanshan; Zhang, Yangjian; Bai, Yongfei; Han, Xingguo; Feng, Xiaojuan] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Chen, Litong] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining, Qinghai, Peoples R China. [Lu, Xiaotao; Wang, Xiaobo] Chinese Acad Sci, Inst Appl Ecol, Shenyang, Liaoning, Peoples R China. [Zhu, Juntao; Zhang, Yangjian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China. [Ma, Wenhong] Inner Mongolia Univ, Sch Ecol & Environm, Hohhot, Peoples R China. [He, Jin-Sheng] Peking Univ, Dept Ecol, Coll Urban & Environm Sci, Beijing, Peoples R China. [He, Jin-Sheng] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland & Agroecosyst, Lanzhou, Gansu, Peoples R China. RP Feng, XJ (通讯作者)，Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China.; Feng, XJ (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. EM xfeng@ibcas.ac.cn TC 9 Z9 9 PD FEB PY 2019 VL 124 IS 2 BP 420 EP 431 DI 10.1029/2018JG004915 UT WOS:000460859100015 DA 2023-03-23 ER PT J AU Sun, Y Wang, YB Yang, WJ Sun, Z Zhao, JP AF Sun, Yan Wang, Yibo Yang, Wenjing Sun, Zhe Zhao, Jinpeng TI Variation in soil hydrological properties on shady and sunny slopes in the permafrost region, Qinghai-Tibetan Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB Soil hydrological properties not only directly influenced soil water content, evapotranspiration, infiltration, and runoff, but also made these factors of concern in arid and semi-arid regions. Prior research has focused on the temporal and spatial variation in soil hydrological properties and the impacts of climate change, ecosystem changes over time or human activities on soil hydrological properties. However, studies conducted on the differences in soil hydrological properties between shady and sunny slopes have seldom been conducted, especially in the permafrost region of the Qinghai-Tibetan Plateau. To investigate the variation in soil hydrological properties on shady and sunny slopes, we chose the Zuomaokongqu watershed of Fenghuo Mountain, which is located on the Qinghai-Tibetan Plateau, as the study area. Three experimental sites were selected in the study area, and the distance between experimental sites was 100m. Based on the differences in altitude and vegetation coverage, five sunny slope sample points and three shady slope sample points were selected in each experimental site. At each of these sample points, the soil water content, soil-saturated conductivity, soil water-retention curve, soil physico-chemical properties, aboveground biomass, and underground biomass were examined in the top 0-50cm of the active layer. The results showed that the soil hydrological properties of shady slopes differed significantly from those of sunny slopes. The soil water content of sunny slopes was 20.9% less than that of shady slopes. The soil-saturated water content of sunny slopes was 12.2% less than that of shady slopes. The soil water content of sunny slopes at -0.3Mpa and -0.7Mpa matric potential was 23.5% and 21.4% less than that of shady slopes, respectively. It was indicated that the soil water-retention capacity of sunny slopes was lower than that of shady slopes. However, the soil-saturated conductivity of sunny slopes was 84.5% larger than that of shady slopes and exceeded the range of soil-saturated conductivity, which was useful for plant growth. Meanwhile, the vegetation coverage on sunny slopes was lower than that on shady slopes, but the soil sand content showed the opposite relationship. Pearson's coefficient analysis results showed that vegetation coverage and soil desertification, which are affected by permafrost degradation, were the main factors influencing soil hydrological properties on shady and sunny slopes. These results will help determine appropriate hydraulic parameters for hydrological models in mountain areas. C1 [Sun, Yan; Wang, Yibo; Yang, Wenjing; Zhao, Jinpeng] Lanzhou Univ, Coll Earth & Environm Sci, Minist Educ, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Gansu, Peoples R China. [Sun, Yan; Wang, Yibo; Sun, Zhe] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. RP Wang, YB (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, Minist Educ, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Gansu, Peoples R China.; Wang, YB (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. EM wangyib@lzu.edu.cn TC 24 Z9 24 PD FEB PY 2019 VL 78 IS 3 AR 100 DI 10.1007/s12665-019-8067-9 UT WOS:000457391900001 DA 2023-03-23 ER PT J AU Wang, C Lin, HL Zhao, YT AF Wang, Chong Lin, Huilong Zhao, Yuting TI A Modification of CIM for Prediction of Net Primary Productivity of the Three-River Headwaters, China SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB The Three-River Headwaters (TRH) region is covered dominantly with alpine meadow, a large part of which is confronting severe degradation as a result of climate change and human-induced influences. The estimation of net primary productivity (NPP) is essential to provide support for scientific management of TRH grassland resources to prevent further degradation. The classification indices-based model (CIM) has been applied in the estimation of NPP and its response to global warming because of its simple structure and easily obtained indices. However, CIM is considered to estimate the potential NPP rather than the actual value. Thus, its application has been restricted. In this study, the normalized difference vegetation index (NDVI) was applied to modify the CIM. Then, CIM and modified CIM were compared with the other three models. The assessment of NPP estimates indicated that the modified CIM had a fair performance among the NPP models (R-2 = 0.42, RMSE = 178.08). All the NPP estimation models revealed that NPP increased from the northwest to the southeast. According to the modified CIM, the mean NPP of TRH grassland was 135.44 gC.m(-2). yr(-1) and the total NPP was 3.22 x 10(13) gC.yr(-1). Among the classes of the grassland of TRH in the comprehensive and sequential classification system (CSCS), the frigid perhumid rain tundra and alpine meadow occupied most of the grassland NPP, which was 3.06 x 10(13) gC.yr(-1).With the help of the NDVI, the modified CIM performed better than the CIM; however, there is still much room for the improvement of CIM in future research. (C) 2018 The Society for Range Management. Published by Elsevier Inc. All rights reserved. C1 [Wang, Chong; Lin, Huilong; Zhao, Yuting] Lanzhou Univ, Key Lab Forage & Livestock Ind Innovat, Chinese Ctr Strateg Res Grassland Agr Dev,Minist, Coll Pastoral Agr Sci & Technol,State Key Lab Gra, Lanzhou 730020, Gansu, Peoples R China. RP Lin, HL (通讯作者)，Rm 416,Yifu Biol Bldg 222,S Tianshui Rd, Lanzhou 730000, Gansu, Peoples R China. EM linhuilong@lzu.edu.cn TC 7 Z9 8 PD FEB PY 2019 VL 72 IS 2 BP 327 EP 335 DI 10.1016/j.rama.2018.11.003 UT WOS:000460292800014 DA 2023-03-23 ER PT J AU Zhang, R Bai, YF Zhang, T Henkin, Z Degen, AA Jia, TH Guo, CC Long, RJ Shang, ZH AF Zhang, Rui Bai, Yanfu Zhang, Tao Henkin, Zalmen Degen, A. Allan Jia, Tianhua Guo, Cancan Long, Ruijun Shang, Zhanhuan TI Driving Factors That Reduce Soil Carbon, Sugar, and Microbial Biomass in Degraded Alpine Grasslands SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB Soil carbon and sugars play key roles in carbon (C) cycling in grassland ecosystems. However, little is known about their changes in quantity and composition in degraded alpine meadows in the Tibetan plateau. We compared vegetation C density, soil organic carbon (SOC) density, and soil sugars in nondegraded (ND), degraded (DA; following artificial restoration), and extremely degraded (ED) grasslands and analyzed the relation among these parameters by redundancy analysis (RDA) and structural equation models (SEMs). Belowground biomass, soil microbial biomass C, soil microbial biomass nitrogen (N), belowground biomass C density, SOC density, and soil sugars were lower in DA and ED grasslands than in ND grasslands. In addition, the ratio of belowground biomass to aboveground biomass (BAR) decreased with an increase in degradation. The ratio of belowground biomass to aboveground biomass was identified as the main indirect driving force of ecosystem C density by affecting total vegetation C and SOC densities. Soil dissolved organic carbon (DOC), microbial biomass carbon (SMBC), neutral sugars (NS), and total nitrogen (TN) were identified as main direct driving forces. The ratio of belowground biomass to aboveground biomass altered DOC. SMBC, NS, and TN and, consequently, was the primary driving force for the alpine meadows' ecosystem C density. It was concluded that land management in alpine meadows should include practices that maintain a relatively high BAR in order to curb degradation and increase ecosystem C density. (C) 2018 The Society for Range Management. Published by Elsevier Inc. All rights reserved. C1 [Zhang, Rui; Bai, Yanfu; Zhang, Tao; Jia, Tianhua; Guo, Cancan; Long, Ruijun; Shang, Zhanhuan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Zhang, Rui] Chinese Acad Sci, Northwest Inst Eco Environm & Resources, Urat Desert Grassland Res Stn, Lanzhou 730000, Gansu, Peoples R China. [Zhang, Rui] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Henkin, Zalmen] Newe Yaar Res Ctr, Dept Agron & Nat Resources, Beef Cattle Sect, Agr Res Org, IL-3009 Ramat Yishay, Israel. [Degen, A. Allan] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, IL-8410500 Beer Sheva, Israel. [Shang, Zhanhuan] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai Prov Key Lab Restorat Ecol Cold Area Nort, Xining 810008, Qinghai, Peoples R China. [Shang, Zhanhuan] Qinghai Univ, Qinghai Acad Anim & Vet Sci, Rangeland Res Inst, Xining 8100016, Qinghai, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. EM shangzhh@lzu.edu.cn TC 9 Z9 9 PD FEB PY 2019 VL 72 IS 2 BP 396 EP 404 DI 10.1016/j.rama.2018.10.001 UT WOS:000460292800020 DA 2023-03-23 ER PT J AU Ai, ZT An, R Chen, YH Huang, LJ AF Ai, Zetian An, Ru Chen, Yuehong Huang, Lijun TI Comparison of hyperspectral HJ-1A/HSI and multispectral Landsat 8 and Sentinel-2A imagery for estimating alpine grassland coverage in the Three-River Headwaters region SO JOURNAL OF APPLIED REMOTE SENSING DT Article AB Accurate estimation of grassland coverage is important in both monitoring grassland growth and promoting grassland management. This study, for the first time, aims to evaluate the alpine grassland coverage estimation performances of four widely used methods [i.e., random forest classification (RFC), regression analysis (RA), multiple endmember spectral mixture analysis (MESMA), and support vector machine regression (SVMR)] from three typical remote sensing images [i.e., hyperspectral (HJ-1A/HSI) image and multispectral (Landsat 8 and Sentinel-2A) images] in the Three-River Headwaters region, China. The total grassland coverage and three levels of grassland subcoverage (i.e., low, moderate, and high coverage) are estimated from the three images by each method. Meanwhile, the overall accuracy (OA) and root-meansquare error (RMSE) of each coverage result are assessed. The experimental results show that (1) for the total grassland coverage estimation, RFC method combined with Sentinel-2A data and RA method used both Landsat 8 and Sentinel-2A data generated the highest OA of 79.4%, whereas the highest OAs of SVMR and MESMA methods are 3% to 14.7% lower than those of RFC and RA methods, (2) for three grassland subcoverage estimation, Landsat 8 data combined with RFC method generated the greatest OAs (100%) and the lowest RMSEs (7.34%) for low grassland coverage and Sentinel-2A data combined with SVMR method obtained the highest OAs (>83.3%) for moderate and high grassland coverage, (3) Sentinel-2A and Landsat 8 data generated higher OAs than HJ-1A/HSI data in estimating the total coverage while Sentinel-2A produced better performance than Landsat 8 in estimating the grassland subcoverage, and (4) SVMR method performed more stably than other methods in estimating alpine grassland coverage. (C) 2019 Society of Photo-Optical Instrumentation Engineers (SPIE) C1 [Ai, Zetian; An, Ru; Chen, Yuehong; Huang, Lijun] Hohai Univ, Sch Earth Sci & Engn, Nanjing, Jiangsu, Peoples R China. [Ai, Zetian] Chuzhou Univ, Sch Geog Informat & Tourism, Chuzhou, Peoples R China. RP An, R (通讯作者)，Hohai Univ, Sch Earth Sci & Engn, Nanjing, Jiangsu, Peoples R China. EM anrunj@163.com TC 1 Z9 1 PD JAN 17 PY 2019 VL 13 IS 1 AR 014504 DI 10.1117/1.JRS.13.014504 UT WOS:000456127700001 DA 2023-03-23 ER PT J AU Miehe, G Schleuss, PM Seeber, E Babel, W Biermann, T Braendle, M Chen, FH Coners, H Foken, T Gerken, T Graf, HF Guggenberger, G Hafner, S Holzapfel, M Ingrisch, J Kuzyakov, Y Lai, ZP Lehnert, L Leuschner, C Li, XG Liu, JQ Liu, SB Ma, YM Miehe, S Mosbrugger, V Noltie, HJ Schmidt, J Spielvogel, S Unteregelsbacher, S Wang, Y Willinghofer, S Xu, XL Yang, YP Zhang, SR Opgenoorth, L Wesche, K AF Miehe, Georg Schleuss, Per-Marten Seeber, Elke Babel, Wolfgang Biermann, Tobias Braendle, Martin Chen, Fahu Coners, Heinz Foken, Thomas Gerken, Tobias Graf, Hans-F. Guggenberger, Georg Hafner, Silke Holzapfel, Maika Ingrisch, Johannes Kuzyakov, Yakov Lai, Zhongping Lehnert, Lukas Leuschner, Christoph Li, Xiaogang Liu, Jianquan Liu, Shibin Ma, Yaoming Miehe, Sabine Mosbrugger, Volker Noltie, Henry J. Schmidt, Joachim Spielvogel, Sandra Unteregelsbacher, Sebastian Wang, Yun Willinghoefer, Sandra Xu, Xingliang Yang, Yongping Zhang, Shuren Opgenoorth, Lars Wesche, Karsten TI The Kobresia pygmaea ecosystem of the Tibetan highlands - Origin, functioning and degradation of the world's largest pastoral alpine ecosystem Kobresia pastures of Tibet SO SCIENCE OF THE TOTAL ENVIRONMENT DT Review AB With 450,000 km(2) Kobresia (syn. Carex) pygmaea dominated pastures in the eastern Tibetan highlands are the world's largest pastoral alpine ecosystemforming a durable turf cover at 3000-6000 m a.s.l. Kobresia's resilience and competitiveness is based on dwarf habit, predominantly below-ground allocation of photo assimilates, mixture of seed production and clonal growth, and high genetic diversity. Kobresia growth is co-limited by livestock-mediated nutrient withdrawal and, in the drier parts of the plateau, low rainfall during the short and cold growing season. Overstocking has caused pasture degradation and soil deterioration over most parts of the Tibetan highlands and is the basis for this man-made ecosystem. Natural autocyclic processes of turf destruction and soil erosion are initiated through polygonal turf cover cracking, and accelerated by soil-dwelling endemic small mammals in the absence of predators. The major consequences of vegetation cover deterioration include the release of large amounts of C, earlier diurnal formation of clouds, and decreased surface temperatures. These effects decrease the recovery potential of Kobresia pastures and make them more vulnerable to anthropogenic pressure and climate change. Traditional migratory rangeland management was sustainable over millennia, and possibly still offers the best strategy to conserve and possibly increase C stocks in the Kobresia turf. (C) 2018 The Authors. Published by Elsevier B.V. C1 [Miehe, Georg; Lehnert, Lukas; Miehe, Sabine] Philipps Univ Marburg, Fac Geog, Marburg, Germany. [Schleuss, Per-Marten] Univ Bayreuth, Soil Biogeochem, Bayreuth, Germany. [Seeber, Elke] Univ Greifswald, Inst Bot & Landscape Ecol, Greifswald, Germany. [Babel, Wolfgang] Univ Bayreuth, Micrometeorol Grp, Bayreuth, Germany. [Babel, Wolfgang; Foken, Thomas] Univ Bayreuth, Bayreuth Ctr Ecol & Environm Res, Bayreuth, Germany. [Biermann, Tobias] Lund Univ, Ctr Environm & Climate Res, Lund, Sweden. [Braendle, Martin; Opgenoorth, Lars] Philipps Univ Marburg, Dept Ecol, Marburg, Germany. [Chen, Fahu] Lanzhou Univ, MOE Key Lab West Chinas Environm Syst, Sch Earth & Environm Sci, Lanzhou, Gansu, Peoples R China. [Coners, Heinz; Leuschner, Christoph; Willinghoefer, Sandra] Univ Gottingen, Dept Plant Ecol & Ecosyst Res, Gottingen, Germany. [Gerken, Tobias] Montana State Univ, Dept Land Resources & Environm Sci, Bozeman, MT 59717 USA. [Graf, Hans-F.] Univ Cambridge, Dept Geog, Ctr Atmospher Sci, Cambridge, England. [Guggenberger, Georg] Leibniz Univ Hannover, Inst Soil Sci, Hannover, Germany. [Hafner, Silke; Kuzyakov, Yakov; Liu, Shibin; Xu, Xingliang] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, Gottingen, Germany. [Holzapfel, Maika; Kuzyakov, Yakov; Wang, Yun; Wesche, Karsten] Senckenberg Museum Gorlitz, Dept Bot, Gorlitz, Germany. [Ingrisch, Johannes] Univ Innsbruck, Inst Ecol Res, Innsbruck, Austria. [Kuzyakov, Yakov] Univ Gottingen, Dept Agr Soil Sci, Gottingen, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan, Russia. [Lai, Zhongping] China Univ Geosci, State Key Lab Biogeol & Environm Geol, Sch Earth Sci, Wuhan, Hubei, Peoples R China. [Li, Xiaogang; Liu, Jianquan] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Coll Life Sci, Lanzhou, Gansu, Peoples R China. [Ma, Yaoming] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing, Peoples R China. [Mosbrugger, Volker] Senckenberg Res Inst, Frankfurt, Germany. [Mosbrugger, Volker] Nat Hist Museum, Frankfurt, Germany. [Noltie, Henry J.] Royal Bot Garden Edinburgh, Edinburgh, Midlothian, Scotland. [Schmidt, Joachim] Univ Rostock, Inst Biosci Gen & Systemat Zool, Rostock, Germany. [Spielvogel, Sandra] Univ Kiel, Dept Soil Sci, Kiel, Germany. [Unteregelsbacher, Sebastian] KIT, Inst Meteorol & Climate Res, Atmospher Environm Res IMK IFU, Garmisch Partenkirchen, Germany. [Xu, Xingliang] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China. [Yang, Yongping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, Beijing, Peoples R China. [Zhang, Shuren] Chinese Acad Sci, Lab Systemat & Evolutionary Bot, Inst Bot, Beijing, Peoples R China. [Wesche, Karsten] German Ctr Integrat Biodivers Res iDiv, Leipzig, Germany. [Wesche, Karsten] Tech Univ Dresden, Int Inst Zittau, Markt 23, D-02763 Zittau, Germany. RP Opgenoorth, L (通讯作者)，Philipps Univ Marburg, Dept Ecol, Marburg, Germany. EM opgenoorth@uni-marburg.de TC 139 Z9 154 PD JAN 15 PY 2019 VL 648 BP 754 EP 771 DI 10.1016/j.scitotenv.2018.08.164 UT WOS:000447805500070 DA 2023-03-23 ER PT J AU Yang, F Niu, KC Collins, CG Yan, XB Ji, YG Ling, N Zhou, XH Du, GZ Guo, H Hu, SJ AF Yang, Fei Niu, Kechang Collins, Courtney G. Yan, Xuebin Ji, Yangguang Ling, Ning Zhou, Xianhui Du, Guozhen Guo, Hui Hu, Shuijin TI Grazing practices affect the soil microbial community composition in a Tibetan alpine meadow SO LAND DEGRADATION & DEVELOPMENT DT Article AB Grazing is the primary land-use activity on the Tibetan Plateau and can affect soil microbes and their function through aboveground vegetation removal, animal trampling, and manure deposition. Two distinct grazing systems (i.e., winter grazing [WG] and annual grazing [AG]) dominate on the Tibetan Plateau, but their effects on soil microbes have rarely been assessed. Taking advantage of a 5-year field experiment that controlled timing and density of grazers via fence exclosures, we examined impacts of different grazing practices on the biomass, diversity, and composition of the soil microbial community in a Tibetan alpine meadow. On the basis of high-throughput sequencing, we found that grazing had no significant effects on bacterial and fungal alpha-diversities but altered their community compositions. Although total soil carbon (TC), total soil nitrogen (TN), and carbon/nitrogen (C/N) were related to both bacterial and fungal community compositions, plant shoot biomass only correlated with bacteria, and soil pH and moisture significantly influenced fungi under grazing. Also, grazing altered plant community composition but did not lead to corresponding changes in bacterial or fungal community composition. Moreover, grazing practices affected the relative abundance of specific bacterial and fungal taxa, reducing Actinobacteria but increasing Basidiomycete fungi in WG. Soil TC and TN were higher, and the soil microbial community was more stable in AG than WG, likely due to more stable litter inputs in AG. Together, these results showed that AG was less disruptive to soil microbes, suggesting that AG may provide a viable option for sustainable utilization and conservation of these fragile alpine systems. C1 [Yang, Fei; Yan, Xuebin; Ji, Yangguang; Ling, Ning; Guo, Hui; Hu, Shuijin] Nanjing Agr Univ, Coll Resources & Environm Sci, Nanjing 210095, Jiangsu, Peoples R China. [Niu, Kechang] Nanjing Univ, Dept Biol, Nanjing 210095, Jiangsu, Peoples R China. [Collins, Courtney G.] Univ Calif Riverside, Dept Bot & Plant Sci, Riverside, CA 92521 USA. [Zhou, Xianhui; Du, Guozhen] Lanzhou Univ, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Hu, Shuijin] North Carolina State Univ, Dept Entomol & Plant Pathol, Raleigh, NC 27695 USA. RP Guo, H; Hu, SJ (通讯作者)，Nanjing Agr Univ, Coll Resources & Environm Sci, Nanjing 210095, Jiangsu, Peoples R China. EM hui.guo@njau.edu.cn; shuijin_hu@hotmail.com TC 56 Z9 65 PD JAN 15 PY 2019 VL 30 IS 1 BP 49 EP 59 DI 10.1002/ldr.3189 UT WOS:000454406600005 DA 2023-03-23 ER PT J AU Ma, QQ Chai, LR Hou, FJ Chang, SH Ma, YS Tsunekawa, A Cheng, YX AF Ma, Qingqing Chai, Linrong Hou, Fujiang Chang, Shenghua Ma, Yushou Tsunekawa, Atsushi Cheng, Yunxiang TI Quantifying Grazing Intensity Using Remote Sensing in Alpine Meadows on Qinghai-Tibetan Plateau SO SUSTAINABILITY DT Article AB Remote sensing data have been widely used in the study of large-scale vegetation activities, which have important significance in estimating grassland yields, determining grassland carrying capacity, and strengthening the scientific management of grasslands. Remote sensing data are also used for estimating grazing intensity. Unfortunately, the spatial distribution of grazing-induced degradation remains undocumented by field observation, and most previous studies on grazing intensity have been qualitative. In our study, we tried to quantify grazing intensity using remote sensing techniques. To achieve this goal, we conducted field experiments at Gansu Province, China, which included a meadow steppe and a semi-arid region. The correlation between a vegetation index and grazing intensity was simulated, and the results demonstrated that there was a significant negative correlation between NDVI and relative grazing intensity (p < 0.05). The relative grazing intensity increased with a decrease in NDVI, and when the relative grazing intensity reached a certain level, the response of NDVI to relative grazing intensity was no longer sensitive. This study shows that the NDVI model can illustrate the feasibility of using a vegetation index to monitor the grazing intensity of livestock in free-grazing mode. Notably, it is feasible to use the remote sensing vegetation index to obtain the thresholds of livestock grazing intensity. C1 [Ma, Qingqing; Chai, Linrong; Hou, Fujiang; Chang, Shenghua; Cheng, Yunxiang] State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China. [Ma, Qingqing; Chai, Linrong; Hou, Fujiang; Chang, Shenghua; Cheng, Yunxiang] Minist Agr & Rural Affairs, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730020, Gansu, Peoples R China. [Ma, Qingqing; Chai, Linrong; Hou, Fujiang; Chang, Shenghua; Cheng, Yunxiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Gansu, Peoples R China. [Ma, Yushou] Qinghai Univ, Acad Anim & Vet Sci, Inst Rangeland Res, Xining 810016, Qinghai, Peoples R China. [Tsunekawa, Atsushi] Tottori Univ, Arid Land Res Ctr, 1390 Hamasaka, Tottori 6800001, Japan. [Cheng, Yunxiang] Inner Mongolia Univ, Sch Ecol & Environm, Hohhot 010021, Inner Mongolia, Peoples R China. RP Cheng, YX (通讯作者)，State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China.; Cheng, YX (通讯作者)，Minist Agr & Rural Affairs, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730020, Gansu, Peoples R China.; Cheng, YX (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Gansu, Peoples R China.; Cheng, YX (通讯作者)，Inner Mongolia Univ, Sch Ecol & Environm, Hohhot 010021, Inner Mongolia, Peoples R China. EM maqq16@lzu.edu.cn; chailr15@lzu.edu.cn; cyhoufj@lzu.edu.cn; cychangsh@lzu.edu.cn; mayushou@sina.com; tsunekawa@alrc.tottori-u.ac.jp; chengyx@lzu.edu.cn TC 26 Z9 26 PD JAN 2 PY 2019 VL 11 IS 2 AR 417 DI 10.3390/su11020417 UT WOS:000457129900121 DA 2023-03-23 ER PT J AU Chai, QL Ma, ZY Chang, XF Wu, GL Zheng, JY Li, ZW Wang, GJ AF Chai, Qinglin Ma, Zhanying Chang, Xiaofeng Wu, Gaolin Zheng, Jiyong Li, Zhongwu Wang, Guojie TI Optimizing management to conserve plant diversity and soil carbon stock of semi-arid grasslands on the Loess Plateau SO CATENA DT Article AB Grassland recovery from degradation is increasingly occurring worldwide. Diverse managements have been considered as effective ways to restore degraded grassland, but it remains unclear how semi-arid grasslands respond to long-term grazing exclusion and fenced mowing. Here, a study was conducted under open grazing, grazing exclusion and fenced mowing in a semi-arid grassland on the Loess Plateau. We measured plant species composition and diversity, plant production, surface litter and soil water and carbon content. Shifts in grassland management led to significant divergence in plant community composition. Long-term grazing exclusion (35 years) significantly increased plant biomass, surface litter, soil water and carbon storage, but suppressed plant diversity compared to open grazing. Conversely, fenced mowing significantly increased plant diversity accompanying with a weak effect on soil carbon. Moreover, mowing significantly reduced surface litter and soil moisture, which have strong implications for nutrient depletion and soil drying. Our results suggest that introducing disturbances are necessary to safeguard biodiversity, and continuous mowing (5 years) belongs to over exploitation of the long-term protected grassland. Therefore, it is essential to optimize management with dual objectives of biodiversity and soil carbon sequestration in the future. C1 [Chai, Qinglin; Ma, Zhanying; Chang, Xiaofeng; Wu, Gaolin; Zheng, Jiyong] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Chai, Qinglin; Ma, Zhanying] Northwest A&F Univ, Coll Forestry, Yangling 712100, Shaanxi, Peoples R China. [Li, Zhongwu] Chinese Acad Sci, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. [Li, Zhongwu] Minist Water Resources, Yangling 712100, Shaanxi, Peoples R China. [Wang, Guojie] Oregon State Univ, Eastern Oregon Univ, Agr Program, La Grande, OR 97850 USA. RP Chang, XF; Zheng, JY (通讯作者)，Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. EM changxf@nwafu.edu.cn; zhjy@ms.iswc.ac.cn TC 15 Z9 15 PD JAN PY 2019 VL 172 BP 781 EP 788 DI 10.1016/j.catena.2018.09.034 UT WOS:000449136800070 DA 2023-03-23 ER PT J AU Chen, QY Lei, TZ Wu, YQ Si, GC Xi, CW Zhang, GX AF Chen, Qiuyu Lei, Tianzhu Wu, Yingqin Si, Guicai Xi, Chuanwu Zhang, Gengxin TI Comparison of Soil Organic Matter Transformation Processes in Different Alpine Ecosystems in the Qinghai-Tibet Plateau SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES DT Article AB Soils in the Qinghai-Tibet Plateau are young in terms of development and form a thin, skeletal soil layer because the gravel parent materials are glaciofluvial deposit, eluvium, and fluvial sediment, which are extremely sensitive to global climate change. The lack of understanding of soil organic matter (SOM) transformation processes in this region hinders the prediction of SOM stocks under future climate conditions. In this study, SOM transformation processes were investigated by density groupings and pyrolysis-gas chromatography/tandem-mass spectrometry (Py-GC-MS/MS) in five alpine ecosystems: alpine desert, alpine grassland, alpine meadow, alpine wetland, and alpine forest. The roles of microbial community in different density fractions were elucidated. Soil samples were separated into three fractions with NaI solution: labile fraction (F-L; rho <= 1.6 g/cm(3)), moderate fraction (F-M; 1.6 < rho < 2.25 g/cm(3)), and recalcitrant fraction (F-R; rho >= 2.25 g/cm(3)). The following results were obtained. (1) The ratios of different fractions (F-M/F-L, F-R/F-M, and F-R/F-L) indicated the transformation processes of SOM, and ratios less than 1 represented degradation. The transformation processes were similar in alpine grassland and meadow and were similar in alpine desert, wetland, and forest but differed from each other. (2) Fungi preferred to degrade plant detritus, which mainly affected F-L, whereas bacteria chiefly affected F-M. (3) Precipitation altered vegetation type and soil pH, thus affecting communities and microorganism activities and resulting in the above differences. These findings highlight the importance of understanding the limited transformation processes of SOM in ecosystems to predict the impact of climate change on SOM preservation. C1 [Chen, Qiuyu; Zhang, Gengxin] Chinese Acad Sci, Key Lab Alpine Ecol & Biodivers, Inst Tibetan Plateau Res, Beijing, Peoples R China. [Chen, Qiuyu] Univ Chinese Acad Sci, Beijing, Peoples R China. [Lei, Tianzhu; Wu, Yingqin; Si, Guicai] Chinese Acad Sci, Key Lab Petr Resources Res, Inst Geol & Geophys, Lanzhou, Gansu, Peoples R China. [Xi, Chuanwu] Univ Michigan, Sch Publ Hlth, Dept Environm Hlth Sci, Ann Arbor, MI 48109 USA. RP Zhang, GX (通讯作者)，Chinese Acad Sci, Key Lab Alpine Ecol & Biodivers, Inst Tibetan Plateau Res, Beijing, Peoples R China. EM zhangg@itpcas.ac.cn TC 11 Z9 14 PD JAN PY 2019 VL 124 IS 1 BP 33 EP 45 DI 10.1029/2018JG004599 UT WOS:000458728400003 DA 2023-03-23 ER PT J AU Feng, L Gan, MY Tian, FP AF Feng, Ling Gan, Mianyu Tian, Fu-Ping TI Effects of Grassland Tourism on Alpine Meadow Community and Soil Properties in the Qinghai-Tibetan Plateau SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES DT Article AB Grassland tourism is a new form of grassland utilization based on grassland ecological environments. Tourism is a double-edged sword that can solve poverty in pastoral areas, but it also causes ecosystem degradation. The impact of tourism on alpine grassland was analyzed by the community and soil properties. Results showed that the most immediate influences of grassland tourism are frequent trampling and crushing. Tramping significantly decreases species diversity. Tourism reduced litter biomass, soil nutrient supply and soil enzyme activities, thus adversely affecting the whole plant-soil system. Therefore, this problem should attract decision makers' attention to balance the relationship between tourism management and economic benefits. Our results suggest that the premise of trade-off between economic benefits and environmental protection is controlling the number of tourists during the peak tourism season, which should be factored for achieving a win-win outcome to dispose of ecosystem degradation and poverty in pastoral areas. C1 [Feng, Ling; Gan, Mianyu] Beijing Int Studies Univ, Tourism Management Dept, Beijing, Peoples R China. [Tian, Fu-Ping] Chinese Acad Agr Sci, Lanzhou Inst Husb & Pharmaceut Sci, Minist Agr Ecol Syst Loess Plateau Area, Lanzhou Sci Observat & Expt Field Stn, Lanzhou, Gansu, Peoples R China. RP Tian, FP (通讯作者)，Chinese Acad Agr Sci, Lanzhou Inst Husb & Pharmaceut Sci, Minist Agr Ecol Syst Loess Plateau Area, Lanzhou Sci Observat & Expt Field Stn, Lanzhou, Gansu, Peoples R China. EM tianfp@163.com TC 4 Z9 4 PY 2019 VL 28 IS 6 BP 4147 EP 4152 DI 10.15244/pjoes/99065 UT WOS:000489645100010 DA 2023-03-23 ER PT J AU Geissler, K Fiedler, S Ni, J Herzschuh, U Jeltsch, F AF Geissler, Katja Fiedler, Sebastian Ni, Jian Herzschuh, Ulrike Jeltsch, Florian TI Combined effects of grazing and climate warming drive shrub dominance on the Tibetan Plateau SO RANGELAND JOURNAL DT Article AB Encroachment of shrubs into the unique pastoral grassland ecosystems of the Tibetan Plateau has significant impact on ecosystem services, especially forage production. We developed a process-based ecohydrological model to identify the relative importance of the main drivers of shrub encroachment for the alpine meadows within the Qinghai province. Specifically, we explored the effects of summer livestock grazing (intensity and type of livestock) together with the effects of climate warming, including interactions between herbaceous and woody vegetation and feedback loops between soil, water and vegetation. Under current climatic conditions and a traditional herd composition, an increasing grazing intensity above a threshold value of 0.32 +/- 0.10 large stock units (LSU) ha(-1) day(-1) changes the vegetation composition from herbaceous towards a woody and bare soil dominated system. Very high grazing intensity (above 0.8 LSU ha(-1) day(-1)) leads to a complete loss of any vegetation. Under warmer conditions, the vegetation showed a higher resilience against livestock farming. This resilience is enhanced when the herd has a higher browser : grazer ratio. A cooler climate has a shrub encroaching effect, whereas warmer conditions increase the cover of the herbaceous vegetation. This effect was primarily due to season length and an accompanied competitive loss of slower growing shrubs, rather than evaporative water loss leading to less soil water in deeper soil layers for deeper rooting shrubs. If climate warming is driving current shrub encroachment, we conclude it is only indirectly so. It would be manifest by an advancing shrubline and could be regarded as a climatic escape of specific shrub species such as Potentilla fruticosa. Under the recent high intensity of grazing, only herding by more browsing animals can potentially prevent both shrub encroachment and the complete loss of herbaceous vegetation. C1 [Geissler, Katja; Fiedler, Sebastian; Jeltsch, Florian] Univ Potsdam, Plant Ecol & Nat Conservat, Muhlenberg 3, D-14476 Potsdam, Germany. [Fiedler, Sebastian] Free Univ Berlin, Inst Biol, Biodivers Theoret Ecol, Altensteinstr 34, D-14195 Berlin, Germany. [Fiedler, Sebastian; Jeltsch, Florian] Berlin Brandenburg Inst Adv Biodivers Res BBIB, D-14195 Berlin, Germany. [Ni, Jian] Zhejiang Normal Univ, Coll Chem & Life Sci, Yingbin Ave 688, Jinhua 321004, Zhejiang, Peoples R China. [Herzschuh, Ulrike] Alfred Wegener Inst Polar & Marine Res, Telegrafenberg A43, D-14473 Potsdam, Germany. [Herzschuh, Ulrike] Univ Potsdam, Dept Earth & Environm Sci, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany. RP Geissler, K (通讯作者)，Univ Potsdam, Plant Ecol & Nat Conservat, Muhlenberg 3, D-14476 Potsdam, Germany. EM kgeissle@uni-potsdam.de TC 1 Z9 3 PY 2019 VL 41 IS 5 BP 425 EP 439 DI 10.1071/RJ19027 UT WOS:000503782100006 DA 2023-03-23 ER PT J AU Jiang, L Chen, H Zhu, QA Yang, YZ Li, MX Peng, CH Zhu, D He, YX AF Jiang, Lin Chen, Huai Zhu, Qiuan Yang, Yanzheng Li, Mingxu Peng, Changhui Zhu, Dan He, Yixin TI Assessment of frozen ground organic carbon pool on the Qinghai-Tibet Plateau SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB PurposeUnder rapid climate change, soil organic carbon (SOC) dynamic in frozen ground may significantly influence terrestrial carbon cycles. The aim of this study was to investigate the storage, spatial patterns, and influencing factors of SOC in frozen ground on the Qinghai-Tibet Plateau, which known as the earth's Third Pole.Materials and methodsUsing the observed edaphic data from China's Second National Soil Survey, we estimated the SOC storage (SOCS) of frozen ground (including permafrost, seasonally, and short time frozen ground) on the plateau with a depth of 0-3m. Furthermore, the effect of vegetation and climate factors on spatial variance of SOC density (SOCD) was analyzed.Results and discussionThe SOCD decreased from the southeastern to the northwestern part of the plateau, and increased with shorten of freezing duration. SOCS of permafrost, seasonally, and short time frozen ground were calculated as 40.9 (34.2-47.6), 26.7 (24.1-29.4), and 6 (5.6-6.4)Pg, making a total of 73.6 (63.9-83.3)Pg in 0-3m depth on the plateau. Normalized difference vegetation index and mean annual precipitation could significantly affect the spatial distribution of SOC in permafrost and seasonally frozen ground.ConclusionsThe soil in plateau frozen ground contained substantial organic carbon, which could be affected by plant and climate variables. However, the heterogeneous landform may make the fate of carbon more complicated in the future. C1 [Jiang, Lin; Chen, Huai; Zhu, Qiuan; Yang, Yanzheng; Li, Mingxu; Peng, Changhui] Northwest A&F Univ, Coll Forestry, Yangling 712100, Shaanxi, Peoples R China. [Jiang, Lin; Zhu, Qiuan; Yang, Yanzheng; Li, Mingxu; Peng, Changhui] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Jiang, Lin; Chen, Huai; Zhu, Dan; He, Yixin] Chinese Acad Sci, Chengdu Inst Biol, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Sichuan, Peoples R China. [Jiang, Lin; Chen, Huai; Zhu, Dan; He, Yixin] Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat Biodivers Conservat Key Lab Sichuan, Chengdu 610041, Sichuan, Peoples R China. [Jiang, Lin; Chen, Huai; Zhu, Dan; He, Yixin] Chinese Acad Sci, Zoige Peatland & Global Change Res Stn, Hongyuan 624400, Sichuan, Peoples R China. [Peng, Changhui] Univ Quebec Montreal, Inst Environm Sci, Dept Biol Sci, Montreal, PQ H3C 3P8, Canada. RP Chen, H (通讯作者)，Northwest A&F Univ, Coll Forestry, Yangling 712100, Shaanxi, Peoples R China.; Chen, H (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Sichuan, Peoples R China.; Chen, H (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat Biodivers Conservat Key Lab Sichuan, Chengdu 610041, Sichuan, Peoples R China.; Chen, H (通讯作者)，Chinese Acad Sci, Zoige Peatland & Global Change Res Stn, Hongyuan 624400, Sichuan, Peoples R China. EM chenhuai@cib.ac.cn TC 13 Z9 14 PD JAN PY 2019 VL 19 IS 1 BP 128 EP 139 DI 10.1007/s11368-018-2006-3 UT WOS:000456207800013 DA 2023-03-23 ER PT J AU Li, Y Dong, SK Gao, QZ Zhang, Y Liu, SL Swift, D Zhao, JB Ganjurjav, H Hu, GZ Wang, XX Yan, YL Cao, XJ Li, WH Luo, WR Zhao, ZZ Li, S Gao, XX AF Li, Yu Dong, Shikui Gao, Qingzhu Zhang, Yong Liu, Shiliang Swift, David Zhao, Jinbo Ganjurjav, Hasbagan Hu, Guozheng Wang, Xuexia Yan, Yulong Cao, Xujuan Li, Wenhan Luo, Wenrong Zhao, Zhenzhen Li, Shuai Gao, Xiaoxia TI Grazing promotes plant functional diversity in alpine meadows on the Qinghai-Tibetan Plateau SO RANGELAND JOURNAL DT Article AB Grazing exclosures and rotational grazing have been extensively applied to prevent grassland degradation and to restore grassland ecosystem function and services. The mechanisms associated with changes in alpine plant traits, and functional diversity under different grazing regimes have not been deeply explored. We examined the variations of plant leaf traits and functional diversity of an alpine meadow under different grazing regimes in a 3-year experiment. The results showed, after 3 years of yak grazing, that the coverage of Stipa capillata increased, whereas that of Kobresia pygmaea decreased under grazing exclosure. Stipa capillata had a lower ratio of leaf nitrogen content to phosphorus content (N : P) under grazing exclosure than under rotational grazing and continuous grazing, whereas Kobresia pygmaea showed no significant differences among grazing treatments. Among grazing regimes, the specific leaf area (SLA) of Stipa capillata was similar, whereas that of Kobresia pygmaea was higher under grazing exclosure. At the interspecific level, leaf area and weight were negatively correlated with SLA, whereas leaf carbon (C) content, leaf N content, leaf C : P and leaf N: P were negatively related to leaf P content and leaf C : N. These findings indicated that growth-defence trade-off strategies might lead to variations in plant traits and coverage. Large-leaved species, due to high maintenance costs, were less commonly distributed in the community, and they were better defended and unpalatable to yaks due to lower SLA, this formed the species coverage distribution pattern of the community. Various N and P utilisation efficiency of different species indicated diverse economic resources utilisation strategies might be due to niche differentiation in the community. Plots that had been excluded from grazing had the lowest functional richness, evenness, and divergence. Rotational and continuous grazing were equivalent in promoting alpine plant functional diversity. C1 [Li, Yu; Dong, Shikui; Liu, Shiliang; Zhao, Jinbo; Zhao, Zhenzhen; Li, Shuai; Gao, Xiaoxia] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Fernow Hall, Ithaca, NY 14853 USA. [Gao, Qingzhu; Ganjurjav, Hasbagan; Hu, Guozheng; Yan, Yulong; Cao, Xujuan; Li, Wenhan; Luo, Wenrong] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Zhang, Yong] Southwest Forestry Univ, Coll Wetlands, Natl Plateau Wetland Res Ctr, Kunming 650224, Yunnan, Peoples R China. [Swift, David] Dept Ecosyst Sci & Sustainabil, Nat Resource Ecol Lab, Ft Collins, CO 80523 USA. [Wang, Xuexia] Beijing Acad Agr & Forestry Sci, Beijing 100097, Peoples R China. [Yan, Yulong] Inner Mongolia Univ, Sch Ecol & Environm, Hohhot 010021, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China.; Dong, SK (通讯作者)，Cornell Univ, Dept Nat Resources, Fernow Hall, Ithaca, NY 14853 USA.; Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM dongshikui@sina.com; gaoqzh@ami.ac.cn TC 10 Z9 11 PY 2019 VL 41 IS 1 BP 73 EP 81 DI 10.1071/RJ18091 UT WOS:000458928400007 DA 2023-03-23 ER PT J AU Wu, HW Li, XY Li, J Zhang, CC He, B Zhang, SY Sun, W AF Wu, Huawu Li, Xiao-Yan Li, Jing Zhang, Cicheng He, Bin Zhang, Siyi Sun, Wei TI Age-related water uptake patterns of alpine plantation shrubs in reforestation region of Qinghai-Tibetan Plateau based on stable isotopes SO ECOHYDROLOGY DT Article AB Sea buckthorn (Hippophae rhamnoides L.) plantations play crucial roles in the prevention of soil erosion and control of desertification on the Qinghai-Tibetan Plateau; however, the limited information on the age-related water uptake patterns of H. rhamnoides and their relationships with associated grasses species weakens our understanding of how these factors influence the management of H. rhamnoides plantations. Therefore, this study investigated the seasonal variations in water uptake patterns of different-aged H. rhamnoides and their associated species via stable isotopes and leaf water potential analyses. The model results showed that seedling (Hs) and juvenile (Hj) H. rhamnoides extracted water mainly from shallow and middle soil layers throughout the growing seasons, whereas mature H. rhamnoides (Hm) exhibited high plasticity, shifting water source between shallow soil water and groundwater when the former become less available. By contrast, the associated grasses (Taraxacum mongolicum, Thermopsis lanceolata, and Polygonum sibiricum) mainly absorbed shallow soil water across the whole growing seasons, suggesting that direct competition for shallow soil water occurred between grasses and H. rhamnoides. In addition, the obviously higher delta C-13 values of Hj with more negative predawn (mean psi(pd), -1.37 MPa) and midday (mean psi(md), -2.23 MPa) leaf water potential indicated the Hj experienced greater water stress relative to Hs and Hm. These results provide new understanding of the seasonal water use strategies of different-aged H. rhamnoides, which will be important for the successful management of plantations in this region. C1 [Wu, Huawu; He, Bin; Sun, Wei] Chinese Acad Sci, Nanjing Inst Geog & Limnol, Key Lab Watershed Geog Sci, Nanjing 210008, Jiangsu, Peoples R China. [Wu, Huawu] Gansu Agr Univ, Minist Educ, Key Lab Grassland Ecosyst, Lanzhou, Gansu, Peoples R China. [Li, Xiao-Yan; Zhang, Cicheng] Beijing Normal Univ, Fac Geog Sci, Sch Nat Resources, Beijing, Peoples R China. [Li, Jing] Jiujiang Coll, Tourism Sch, Jiujiang, Peoples R China. [Zhang, Siyi] Guangdong Inst Ecoenvironm Sci & Technol, Guangdong Key Lab Integrated Agroenvironm Pollut, Guangzhou, Guangdong, Peoples R China. RP Wu, HW; Sun, W (通讯作者)，Chinese Acad Sci, Nanjing Inst Geog & Limnol, Key Lab Watershed Geog Sci, Nanjing 210008, Jiangsu, Peoples R China. EM wuhuawu416@163.com; wsun@niglas.ac.cn TC 11 Z9 11 PD JAN PY 2019 VL 12 IS 1 AR e2049 DI 10.1002/eco.2049 UT WOS:000454601400001 DA 2023-03-23 ER PT J AU Xu, DW Chen, BR Yan, RR Yan, YC Sun, XB Xu, LJ Xin, XP AF Xu, Dawei Chen, Baorui Yan, Ruirui Yan, Yuchun Sun, Xinbo Xu, Lijun Xin, Xiaoping TI Quantitative monitoring of grazing intensity in the temperate meadow steppe based on remote sensing data SO INTERNATIONAL JOURNAL OF REMOTE SENSING DT Article AB Grazing intensity (GI) is difficult to measure accurately because of the diversity of grazing livestock, their mobility in the grazing space and the uncertainty of grazing times. Thus, GI monitoring is often only qualitative, while quantitative monitoring is scarce. In this study, models correlating GI, the normalized difference vegetation index (NDVI) and aboveground biomass (AGB) were established based on a controlled GI experiment. The GI derived from NDVI was evaluated using the GI derived from AGB samples, under the principle that AGB is similar for the same GI in the same grassland type. The results showed that the appropriate time to build the model in the study area was from July to August, when there was a negative correlation between GI and NDVI. The simulated GI derived from NDVI was similar to GI derived from AGB, and the R-2 (coefficient of determination) values for fresh weight and dry weight were 0.3770 and 0.4292, respectively; the root mean square error (RMSE) were 0.2302 and 0.1953 animal units (AU) ha(-1) (1AU=500kg of adult cattle); and the relative error from -20% to 20% accounted for 62.07% and 72.41% of the total samples. Most of the study area was under heavy grazing according to monitoring results from 2010 to 2016, except for a few pastures with rational utilization (0.23AU ha(-1) - 0.46AU ha(-1)), and continuous heavy grazing often occurred for many years without rest grazing. C1 [Xu, Dawei; Chen, Baorui; Yan, Ruirui; Yan, Yuchun; Xu, Lijun; Xin, Xiaoping] Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Hulunber Grassland Ecosyst Observat & Res Stn, Beijing, Peoples R China. [Sun, Xinbo] Agr Univ Hebei, Key Lab Crop Growth Regulat Hebei Prov, Baoding, Peoples R China. RP Xin, XP (通讯作者)，Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Hulunber Grassland Ecosyst Observat & Res Stn, Beijing, Peoples R China. EM xinxiaoping@caas.cn TC 9 Z9 9 PY 2019 VL 40 IS 5-6 SI SI BP 2227 EP 2242 DI 10.1080/01431161.2018.1500733 UT WOS:000464043900038 DA 2023-03-23 ER PT J AU Yao, X Chai, Q Chen, TX Chen, ZJ Wei, XK Bao, GS Song, ML Wei, WR Zhang, XX Li, CJ Nan, ZB AF Yao, Xiang Chai, Qing Chen, Taixiang Chen, Zhenjiang Wei, Xuekai Bao, Gensheng Song, Meiling Wei, Wanrong Zhang, Xingxu Li, Chunjie Nan, Zhibiao TI Disturbance by grazing and the presence of rodents facilitates the dominance of the unpalatable grass Achnatherum inebrians in alpine meadows of northern China SO RANGELAND JOURNAL DT Article AB Unpalatable plants reportedly serve as a biodiversity refuge. However, few studies have been conducted to evaluate how unpalatable plants impact vegetation composition in alpine ecosystems. In the present study we investigated alpine meadows at four sites in four different prefectures on the eastern Qinghai-Tibetan Plateau of Qinghai Province, China. The study sites included meadows grazed by livestock (AO) and others in the vicinity colonised by the unpalatable grass, Achnatherum inebrians (AI), which the livestock avoided. The results showed: (1) palatable graminoid species were significantly different in the two groups: AO plots were dominated by Kobresia spp. (sedges), whereas AI plots were dominated by Poa pratensis and Elymus nutans (grasses); (2) graminoid diversity was significantly higher in AI than in AO plots; (3) grasses had significantly more seeds in AI than in AO plots. We suggest a three-step process for the invasion of A. inebrians into overgrazed alpine meadows in Northern China. First, soil is disturbed by rodents. Second, disturbed soil is invaded by A. inebrians. Third, the A. inebrians community is colonised by palatable grasses such as Elymus, Poa, Leymus and Stipa spp. C1 [Yao, Xiang; Chai, Qing; Chen, Taixiang; Chen, Zhenjiang; Wei, Xuekai; Wei, Wanrong; Zhang, Xingxu; Li, Chunjie; Nan, Zhibiao] Lanzhou Univ, Coll Pastoral Agr Sci & Technol,State Key Lab Gra, Minist Educ,Key Lab Grassland Livestock Ind Innov, Minist Agr & Rural Affairs,Engn Res Ctr Grassland, Lanzhou 730020, Gansu, Peoples R China. [Bao, Gensheng; Song, Meiling] Qinghai Univ, Qinghai Acad Anim & Vet Sci, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. RP Li, CJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol,State Key Lab Gra, Minist Educ,Key Lab Grassland Livestock Ind Innov, Minist Agr & Rural Affairs,Engn Res Ctr Grassland, Lanzhou 730020, Gansu, Peoples R China. EM chunjie@lzu.edu.cn TC 7 Z9 7 PY 2019 VL 41 IS 4 BP 301 EP 312 DI 10.1071/RJ18096 UT WOS:000487036500002 DA 2023-03-23 ER PT J AU Li, CY Peng, F Xue, X You, QG Lai, CM Zhang, WJ Cheng, YX AF Li, Chengyang Peng, Fei Xue, Xian You, Quangang Lai, Chimin Zhang, Wenjuan Cheng, Yunxiang TI Productivity and Quality of Alpine Grassland Vary With Soil Water Availability Under Experimental Warming SO FRONTIERS IN PLANT SCIENCE DT Article AB The plant productivity of alpine meadow is predicted to generally increase under a warming climate, but it remains unclear whether the positive response rates will vary with soil water availability. Without consideration of the response of community composition and plant quality, livestock grazing under the current stocking rate might still lead to grassland degradation, even in meadows with high plant biomass. We have conducted a warming experiment from 2010 to 2017 to examine the interactive effects of warming and soil water availability on plant growth and forage quality at individual and functional group levels in an alpine meadow located in the permafrost region of the Qinghai-Tibetan Plateau. Warming-induced changes in community composition, biomass, and forage quality varied with soil water availability. Under dry conditions, experimental warming reduced the relative importance of grasses and the aboveground biomass by 32.37 g m(-2) but increased the importance value of forbs. It also increased the crude fat by 0.68% and the crude protein by 3.19% at the end of summer but decreased the acid detergent fiber by 5.59% at the end of spring. The increase in crude fat and protein and the decrease in acid detergent fiber, but the decrease in aboveground biomass and increase the importance value of forbs, which may imply a deterioration of the grassland. Under wet conditions, warming increased aboveground biomass by 29.49 g m(-2) at the end of spring and reduced acid detergent fiber by 8.09% at the end of summer. The importance value of grasses and forbs positively correlated with the acid detergent fiber and crude protein, respectively. Our results suggest that precipitation changes will determine whether climate warming will benefit rangelands on the Qinghai- Tibetan Plateau, with drier conditions suppressing grassland productivity, but wetter conditions increasing production while preserving forage quality. C1 [Li, Chengyang; Peng, Fei; Xue, Xian; You, Quangang; Lai, Chimin; Zhang, Wenjuan] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou, Gansu, Peoples R China. [Li, Chengyang; Zhang, Wenjuan] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. [Peng, Fei] Int Platform Dry Res & Educ, Tottori, Japan. [Peng, Fei] Tottori Univ, Arid Land Res Ctr, Tottori, Japan. [Lai, Chimin] Fujian Agr & Forestry Univ, Coll Forestry, Fuzhou, Fujian, Peoples R China. [Cheng, Yunxiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat,Minist Ag, Lanzhou, Gansu, Peoples R China. RP Peng, F (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, Lanzhou, Gansu, Peoples R China.; Peng, F (通讯作者)，Int Platform Dry Res & Educ, Tottori, Japan.; Peng, F (通讯作者)，Tottori Univ, Arid Land Res Ctr, Tottori, Japan. EM pengfei@lzb.ac.cn TC 28 Z9 31 PD DEC 14 PY 2018 VL 9 AR 1790 DI 10.3389/fpls.2018.01790 UT WOS:000453343800001 DA 2023-03-23 ER PT J AU Luo, JF Liu, XM Yang, J Liu, YG Zhou, JX AF Luo, Jiufu Liu, Xuemin Yang, Jun Liu, Yuguo Zhou, Jinxing TI Variation in plant functional groups indicates land degradation on the Tibetan Plateau SO SCIENTIFIC REPORTS DT Article AB Plant functional groups (PFGs) have been increasingly introduced in land degradation (LD) studies; however, it is unclear whether PFGs can indicate LD. Here, we selected five different degraded lands (i.e., pristine and, lightly, moderately, seriously and extremely degraded) higher than 4650 m on the Tibetan Plateau. In addition, we investigated floristic metrics (i.e., composition, height, cover, biomass and abundance) and soil conditions (e.g., moisture, temperature and gravel ratio) by sampling 225 subplots. We found 75 vascular plants that consist of sedges (Cyperaceae), grasses (Gramineae), legumes, forbs, cushion plants and shrubs PFGs. LD dramatically deteriorated soil conditions, vegetation cover and productivity, however, improved species diversity. Moreover, cover and productivity showed a hump-shaped relationship with LD intensification in legumes, grasses and forbs and decreased mainly in sedges. Productivity increased considerably in cushion plants and shrubs on the extremely degraded land. Major characteristics of the LD process were the replacement of Kobresia spp. by Carex spp. in sedges; cushion plants significantly expanded, and shrubs appeared on the extremely degraded land. We, thus, confirm that the PFG variations are likely to indicate a LD process and demonstrate ways of using PFGs to assess LD status on the Tibetan Plateau. C1 [Luo, Jiufu; Liu, Xuemin; Zhou, Jinxing] Beijing Forestry Univ, Sch Soil & Water Conservat, Key Lab State Forestry Adm Soil & Water Conservat, Beijing 100083, Peoples R China. [Luo, Jiufu; Liu, Xuemin; Zhou, Jinxing] Beijing Forestry Univ, Sch Soil & Water Conservat, Jianshui Res Field Stn, Beijing 100083, Peoples R China. [Yang, Jun] Tsinghua Univ, Ctr Earth Syst Sci, Minist Educ, Key Lab Earth Syst Modeling, Beijing, Peoples R China. [Liu, Yuguo] Chinese Acad Forestry, Inst Desertificat Studies, 10 Huaishuju Rd, Beijing 100091, Peoples R China. RP Zhou, JX (通讯作者)，Beijing Forestry Univ, Sch Soil & Water Conservat, Key Lab State Forestry Adm Soil & Water Conservat, Beijing 100083, Peoples R China.; Zhou, JX (通讯作者)，Beijing Forestry Univ, Sch Soil & Water Conservat, Jianshui Res Field Stn, Beijing 100083, Peoples R China. EM zjx001@bjfu.edu.cn TC 14 Z9 14 PD DEC 4 PY 2018 VL 8 AR 17606 DI 10.1038/s41598-018-36028-5 UT WOS:000452084600014 DA 2023-03-23 ER PT J AU Ge, J Meng, BP Liang, TG Feng, QS Gao, JL Yang, SX Huang, XD Xie, HJ AF Ge, Jing Meng, Baoping Liang, Tiangang Feng, Qisheng Gao, Jinlong Yang, Shuxia Huang, Xiaodong Xie, Hongjie TI Modeling alpine grassland cover based on MODIS data and support vector machine regression in the headwater region of the Huanghe River, China SO REMOTE SENSING OF ENVIRONMENT DT Article AB Monitoring changes in grassland cover is essential in assessment of grassland health as well as the effects of anthropogenic interventions and global climate change on grassland ecosystems. Remote sensing is an effective approach for providing rapid and dynamic monitoring of vegetation cover over large grassland areas. In this study, four types of remote sensing retrieval models (i.e., pixel dichotomy models, univariate vegetation index (VI) regression models, multivariate regression models, and a support vector machine (SVM) model) are built to derive grassland cover based on moderate resolution imaging spectroradiometer (MODIS) data and the measured grassland cover data collected by unmanned aerial vehicle during the grassland peak growing season from 2014 to 2016. The optimal model is then used to map the spatial distribution of grassland cover and its dynamic change in the headwater region of the Huanghe River (Yellow River) (HRHR) of the northeastern Tibetan Plateau over the 16 years period (2001 to 2016). The results show that (1) the pixel dichotomy models based on MODIS VI data are inappropriate for estimating grassland cover in the HRHR when their endmembers (VIsoil and VIved are determined based only on the MODIS data; (2) the multivariate regression models present better performance than the univariate VI (normalized difference vegetation index (NDVI) or enhanced vegetation index (EVI)) models; (3) MODIS NDVI outperforms MODIS EVI for modeling grassland cover in the study area; (4) the SVM model based on nine factors is the optimal model (R-2: 0.75 and RMSE: 6.85%) for monitoring alpine grassland cover in the study area; and (5) majority of the grassland area (59.9%) of the HRHR showed increase in yearly maximum grassland cover from 2001 to 2016, while the average yearly maximum grassland cover for the 16 years exhibited a generally increasing trend from west to east and from north to south. This study provides a more suitable remote sensing inversion model to greatly improve the accuracy of modeling alpine grassland cover in the HRHR, and to better assess grassland health status and the impacts of warming climate to grasslands in regions of remote and harsh environments. C1 [Ge, Jing; Meng, Baoping; Liang, Tiangang; Feng, Qisheng; Gao, Jinlong; Yang, Shuxia; Huang, Xiaodong] Lanzhou Univ, Coll Pastoral Agr Sci & Technol,Minist Educ, Engn Res Ctr Grassland Ind,Minist Agr & Rural Aff, State Key Lab Grassland Agroecosyst,Key Lab Grass, Lanzhou 730000, Gansu, Peoples R China. [Xie, Hongjie] Univ Texas San Antonio, Dept Geol Sci, Lab Remote Sensing & Geoinformat, San Antonio, TX 78249 USA. RP Liang, TG (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol,Minist Educ, Engn Res Ctr Grassland Ind,Minist Agr & Rural Aff, State Key Lab Grassland Agroecosyst,Key Lab Grass, Lanzhou 730000, Gansu, Peoples R China. EM tgliang@lzu.edu.cn TC 74 Z9 81 PD DEC 1 PY 2018 VL 218 BP 162 EP 173 DI 10.1016/j.rse.2018.09.019 UT WOS:000449449800012 DA 2023-03-23 ER PT J AU Ma, WW Alhassan, ARM Wang, YS Li, G Wang, H Zhao, JM AF Ma, Weiwei Alhassan, Abdul-Rauf M. Wang, Yuesi Li, Guang Wang, Hui Zhao, Jinmei TI Greenhouse gas emissions as influenced by wetland vegetation degradation along a moisture gradient on the eastern Qinghai-Tibet Plateau of North-West China SO NUTRIENT CYCLING IN AGROECOSYSTEMS DT Article AB Vegetation loss and plant diversity decline in wetlands affect carbon and nitrogen cycling and consequently influence gas fluxes. Although extensive grazing by livestock and climate change have caused significant physical degradation of wetlands on the Qinghai-Tibet Plateau (QTP), and created a clear drainage gradient, the impact on greenhouse gas (GHG) emissions associated with this change has rarely been reported. A 3-year study (2013-2015) was conducted to examine the effect of vegetation change and seasonality on ecosystem respiration, methane (CH4) and nitrous oxide (N2O) fluxes in four classes of wetlands with distinct magnitudes of vegetation degradation: healthy vegetation (HV), slightly degraded (SD), moderately degraded, and heavily degraded (HD). We used the dark static chamber-chromatography method to measure the gas fluxes. Highly degraded wetlands were larger C and GHG sources than HV, despite lower methane emissions, due to the loss of gross primary production. SD and HD exhibited the highest cumulative mean annual ecosystem respiration and N2O emissions, respectively. Ecosystem respiration and CH4 fluxes were much higher during the growing seasons than in the non-growing seasons. Ecosystem respiration and N2O fluxes were positively correlated with soil and air temperatures. This points at a potential effect of global warming on GHG emissions from the QTP wetlands. Top soil (0-20cm) moisture content significantly correlated positively with CH4 fluxes. Vegetation loss led to a reduced C uptake and increased global warming potential. Therefore, we recommend soil conservation measures and reduced livestock grazing in the wetlands in order to conserve their role as carbon sinks. C1 [Ma, Weiwei; Alhassan, Abdul-Rauf M.; Li, Guang; Wang, Hui; Zhao, Jinmei] Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Gansu, Peoples R China. [Ma, Weiwei; Wang, Yuesi] Chinese Acad Sci, Inst Atmospher Phys, Beijing 100029, Peoples R China. RP Li, G (通讯作者)，Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Gansu, Peoples R China. EM maww@gsau.edu.cn TC 13 Z9 22 PD DEC PY 2018 VL 112 IS 3 BP 335 EP 354 DI 10.1007/s10705-018-9950-6 UT WOS:000448525500004 DA 2023-03-23 ER PT J AU Wang, L Gan, YT Wiesmeier, M Zhao, GQ Zhang, RY Han, GD Siddique, KHM Hou, FJ AF Wang, Li Gan, Yantai Wiesmeier, Martin Zhao, Guiqin Zhang, Ruiyang Han, Guodong Siddique, Kadambot H. M. Hou, Fujiang TI Grazing exclusion-An effective approach for naturally restoring degraded grasslands in Northern China SO LAND DEGRADATION & DEVELOPMENT DT Article AB Nearly 90% of the 390 million ha of grasslands in northern China are degraded. 'Grazing exclusion' has been implemented as a nature-based solution to rejuvenate degraded grasslands, but the effectiveness of the rejuvenation processes is uncertain. Here, we investigated the effects of grazing exclusion on aboveground plant community traits, soil physiochemical and biological properties, and the mechanisms responsible for enhanced grassland rejuvenation. A meta-analysis across various studies was used to assess the effectiveness. On average, grazing exclusion improved vegetation coverage by 18.5 percentage points and increased aboveground biomass by 1.13 t ha-1 and root biomass by 1.27 t ha-1, which represent an increase of 84%, 246%, and 31%, respectively, compared with continuous grazing practices. Grazing exclusion reduced soil bulk density by 13.7% and increased soil water content by 68.9%. Grasslands under grazing exclusion increased soil organic carbon (SOC) in the 0-to 15-cm depth by 3.95 (+/- 0.35 Std err) t ha-1 and total soil N, available N, and total soil P in the 0-to 40-cm depth by 2.39 (+/- 0.14), 0.83 (+/- 0.37), and 1.96 (+/- 0.44) t ha-1, respectively, compared with continuous grazing; these values represent an increase of 31%, 25%, 23%, and 14%, respectively. Prolonging the duration (years) of grazing practices enlarged the differences in SOC and soil N content between grazing exclusion and continuous grazing. Grazing exclusion has improved plant community traits and enhanced soil physiochemical and biological properties of degraded grasslands, and thus, this 'nature-based' approach can serve as an effective means to rejuvenate degraded grasslands. C1 [Wang, Li] Gansu Agr Univ, Gansu Prov Key Lab Aridland Crop Sci, Lanzhou 730070, Gansu, Peoples R China. [Wang, Li] Gansu Agr Univ, Gansu Key Lab Crop Genet & Germplasm Enhancement, Lanzhou 730070, Gansu, Peoples R China. [Wang, Li] Gansu Agr Univ, Coll Life Sci & Technol, Lanzhou 730070, Gansu, Peoples R China. [Gan, Yantai] Agr & Agri Food Canada, Res & Dev Ctr, Swift Current, SK S9H 3X2, Canada. [Wiesmeier, Martin] Tech Univ Munich, TUM Sch Life Sci Weihenstephan, Soil Sci, D-85350 Freising Weihenstephan, Germany. [Zhao, Guiqin] Gansu Agr Univ, Coll Grassland Sci, Lanzhou 730070, Gansu, Peoples R China. [Zhang, Ruiyang; Han, Guodong] Inner Mongolia Agr Univ, Coll Grassland Resources & Environm, Hohhot 010011, Peoples R China. [Siddique, Kadambot H. M.] Univ Western Australia, UWA Inst Agr, Perth, WA 6001, Australia. [Siddique, Kadambot H. M.] Univ Western Australia, Sch Agr & Environm, Perth, WA 6001, Australia. [Hou, Fujiang] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China. [Hou, Fujiang] Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Gansu, Peoples R China. [Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Gansu, Peoples R China. RP Wang, L (通讯作者)，Gansu Agr Univ, Gansu Prov Key Lab Aridland Crop Sci, Lanzhou 730070, Gansu, Peoples R China.; Wang, L (通讯作者)，Gansu Agr Univ, Gansu Key Lab Crop Genet & Germplasm Enhancement, Lanzhou 730070, Gansu, Peoples R China.; Wang, L (通讯作者)，Gansu Agr Univ, Coll Life Sci & Technol, Lanzhou 730070, Gansu, Peoples R China.; Hou, FJ (通讯作者)，Lanzhou Univ, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China.; Hou, FJ (通讯作者)，Lanzhou Univ, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs, Lanzhou 730020, Gansu, Peoples R China.; Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Gansu, Peoples R China. EM wangl@gsau.edu.cn; cyhoufj@lzu.edu.cn TC 57 Z9 63 PD DEC PY 2018 VL 29 IS 12 BP 4439 EP 4456 DI 10.1002/ldr.3191 UT WOS:000465580100019 DA 2023-03-23 ER PT J AU Xie, HH Wu, QG Hu, JY Yu, LF Bie, PF Wang, H Deng, DZ AF Xie, H. H. Wu, Q. G. Hu, J. Y. Yu, L. F. Bie, P. F. Wang, H. Deng, D. Z. TI Changes in Soil Physical and Chemical Properties During the Process of Alpine Meadow Degradation along the Eastern Qinghai-Tibet Plateau SO EURASIAN SOIL SCIENCE DT Article AB Soil moisture, nutrients and environmental conditions have extremely vital effects on vegetation growth and microbial activities in terrestrial ecosystems. To study the changes of soil physical and chemical properties as affected by degradation along the eastern margin of the Tibetan Plateau, using the largest wetland in Ruoergai as the research sample for two consecutive years, we tested the soil bulk density, the soil moisture content, the pH value, the content of organic C, total N and total P of 0 similar to 20 cm and 20 similar to 40 cm in different degradation degree (light, moderate, serious and non-degraded alpine meadow). The resultsshowthat: (1) Degradation had profound effects on the soil physical properties and chemical properties. with the intensification of the alpine meadow degradation in the eastern margin of the Qinghai-Tibet Plateau, the soil organic carbon, total nitrogen, total phosphorus and soil water content decreased significantly but soil bulk density increased significantly. (2) the soil organic carbon, total nitrogen, total phosphorus contents and soil water content increased with the increase of soil depth, however, the soil bulk density show the opposite regular. (3) The correlation analysis indicated that there was an extremely significant positive correlation between soil organic carbon and total nitrogen, total phosphorus, soil water, and the correlation coefficients were 0.822, 0.907 and 0.885 respectively (P < 0.01). There was an extremely significant positive relationship between the pH and the soil bulk density (r = 0.488, p < 0.01), while a significant negative relationship between pH and soil water (r = -0.387, p < 0.05). Overall, these results suggested that soil degradation not only changed the soil physical properties but also affected the soil chemical properties indirectly. Protecting surface vegetation and reducing wind erosion could be a good way to curb degradation. C1 [Xie, H. H.; Hu, J. Y.; Bie, P. F.; Wang, H.] Mianyang Normal Univ, Coll Life Sci & Biotechnol, Mianyang 621000, Peoples R China. [Wu, Q. G.] Mianyang Normal Univ, Ecol Secur & Protect Key Lab Sichuan Prov, Mianyang 621000, Peoples R China. [Yu, L. F.; Deng, D. Z.] Sichuan Acad Forestry, Chengdu 611130, Sichuan, Peoples R China. RP Xie, HH (通讯作者)，Mianyang Normal Univ, Coll Life Sci & Biotechnol, Mianyang 621000, Peoples R China. EM 1531123273@qq.com TC 8 Z9 10 PD DEC PY 2018 VL 51 IS 12 BP 1440 EP 1446 DI 10.1134/S1064229318130045 UT WOS:000458178600006 DA 2023-03-23 ER PT J AU Xue, ZS Lyu, XG Chen, ZK Zhang, ZS Jiang, M Zhang, K Lyu, YL AF Xue Zhenshan Lyu Xianguo Chen Zhike Zhang Zhongsheng Jiang Ming Zhang Kun Lyu Yonglei TI Spatial and Temporal Changes of Wetlands on the Qinghai-Tibetan Plateau from the 1970s to 2010s SO CHINESE GEOGRAPHICAL SCIENCE DT Article AB Wetlands on the Qinghai-Tibetan Plateau (QTP) perform a dazzling array of vital ecological functions and are one of the most fragile ecosystems in the world. Timely and accurate information describing wetland resources and their changes over time is becoming more important in their protection and conservation. By using remote sensing data, this study intended to investigate spatial distribution and temporal variations of wetlands on the QTP at different watershed scales from 1970s to 2010s. Results show that wetlands on the QTP have undergone widespread degradation from 1970s to 2010s, with nearly 6.4% of their area being lost. Areas of freshwater marsh, salt marsh and wet meadow declined by 46.6%, 53.9% and 15.6%, respectively, while lake area increased by 14.6%. The most extensive losses of natural wetlands have occurred in endorheic basins, such as in the Kunlun-Altun-Qilian Drainage Basin and Qiangtang Basin, which shrank by 44.5% and 33.1%, respectively. A pronounced increase in temperature tends to facilitate the evaporation process and reduce water availability for wetlands. One-third of the wetlands on the QTP are under threat of being submerged due to lakes rising in recent years. More research is needed to gain insight into the interaction mechanisms behind observed variations and potential impacts from further warming in the future. C1 [Xue Zhenshan; Lyu Xianguo; Zhang Zhongsheng; Jiang Ming] Chinese Acad Sci, Northeast Inst Geog & Agroecol, Res Ctr Wetland Ecol & Environm, Changchun 130102, Jilin, Peoples R China. [Chen Zhike] Heilongjiang Agr Reclamat Survey Design & Res Ins, Harbin 150090, Heilongjiang, Peoples R China. [Jiang Ming] Jilin Prov Joint Key Lab Changbai Mt Wetland & Ec, Changchun 130102, Jilin, Peoples R China. [Zhang Kun] Southwest Forestry Coll, Dept Environm Sci & Engn, Kunming 650224, Yunnan, Peoples R China. [Lyu Yonglei] Forestry Dept Tibet, Inst Tibetan Forestry Survey & Planning, Lhasa 850000, Peoples R China. RP Zhang, ZS (通讯作者)，Chinese Acad Sci, Northeast Inst Geog & Agroecol, Res Ctr Wetland Ecol & Environm, Changchun 130102, Jilin, Peoples R China. EM zzslycn@neigae.ac.cn TC 24 Z9 26 PD DEC PY 2018 VL 28 IS 6 BP 935 EP 945 DI 10.1007/s11769-018-1003-1 UT WOS:000449877100003 DA 2023-03-23 ER PT J AU Zhang, HY Fan, JW Wang, JB Cao, W Harris, W AF Zhang, Haiyan Fan, Jiangwen Wang, Junbang Cao, Wei Harris, Warwick TI Spatial and temporal variability of grassland yield and its response to climate change and anthropogenic activities on the Tibetan Plateau from 1988 to 2013 SO ECOLOGICAL INDICATORS DT Article AB Accurate and periodic assessment of grassland yield (GY) is of great importance for the management of high altitude plateau grasslands. The Tibetan Plateau (TP) is a very important pastoral area that provides a microcosm of typical alpine grassland ecosystems. Based on remote sensing data, meteorological datasets and observational plant biomass data, we used the Global Production Efficiency Model and Soil and Atmosphere Model (GLOPEMCEVSA) to estimate GY and its response to climate change and anthropogenic activities on the TP from 1988 to 2013. We quantitatively analyzed spatiotemporal dynamic changes of GY for four geomorphological divisions and five main grassland types. For the 26 years of the study, average annual total GY was 515.8 kg/ha/yr and gradually decreased from the southeast to the northwest of the TP. Annual GY fluctuated from year to year but had an overall positive trend (4.2 kg/ha/yr). Spatiotemporal variation of GY was greatly influenced by spatial heterogeneity. For the total area, the proportion showing a significant increase in GY was 45.2%, while only 12.6% showed a significant decrease. For the main grassland types, GY of Alpine Meadow was highest and had the highest slope of increase. The pattern of decrease of GY from the southeast to the northwest was predominantly related to climate gradients. Regional correlation analysis indicated that warming temperature promoted positive increase of GY for almost all the region. Annual precipitation was related to a less significant decreasing trend of GY over all the TP apart from an increase of GY in the middle area of the north. The grazing pressure index decreased over the years by control of livestock numbers, the reduction of grazing pressure assisting restoration of alpine grasslands. However, grazing pressure on the TP in 2013 remained too high and overloaded. Nevertheless, grassland protection and restoration projects have mitigated grassland degradation in some areas, promoted grassland restoration, and increased incomes of herdsmen. The study indicates that continuation of these projects is critical for the restoration and sustainable use of the TP grasslands. C1 [Zhang, Haiyan; Fan, Jiangwen; Wang, Junbang; Cao, Wei] Chinese Acad Sci, Key Lab Land Surface Pattern & Simulat, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Zhang, Haiyan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Junbang] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Harris, Warwick] Landcare Res, POB 69040, Lincoln 7640, New Zealand. RP Fan, JW (通讯作者)，Chinese Acad Sci, Key Lab Land Surface Pattern & Simulat, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM zhanghy.13b@igsnrr.ac.cn; fanjw@igsnrr.ac.cn; jbwang@igsnrr.ac.cn; caowei@igsnrr.ac.cn TC 39 Z9 43 PD DEC PY 2018 VL 95 BP 141 EP 151 DI 10.1016/j.ecolind.2018.05.088 PN 1 UT WOS:000456907400015 DA 2023-03-23 ER PT J AU Cao, JJ Holden, NM Adamowski, JF Deo, RC Xu, XY Feng, Q AF Cao, J. J. Holden, N. M. Adamowski, J. F. Deo, R. C. Xu, X. Y. Feng, Q. TI Can individual land ownership reduce grassland degradation and favor socioeconomic sustainability on the Qinghai-Tibetan Plateau? SO ENVIRONMENTAL SCIENCE & POLICY DT Article AB Land degradation neutrality (LDN) was introduced to provide a policy framework to achieve Sustainable Development Goal (SDG) 15. Land use policy and management changes can alter the status of land-based natural capital, and exert an influence on ecosystem functioning and interactions with a socio-ecological system. Over the last 30 years, continued efforts to maintain the socioeconomic sustainability of the Qinghai-Tibetan Plateau (QTP) led to the implementation of a unique ownership policy of individual households that were contracted to use defined grassland properties rather than collective nomadic practices. Two distinct types of privately-owned grassland properties now exist: individual private property (IPP) and jointly managed private property (JPP). The influence of IPP (vs. JPP) on grassland degradation has been the subject of a limited number of studies that are reviewed in this paper to help estimate some baseline indicator values for LDN on the QTP. Grasslands under IPP were more degraded according to soil and vegetation measurements, which were indicative of excessive vegetation removal and trampling due to grazing pressure. This pressure occurred because livestock mobility was limited by the imposed restrictions of fencing. A review of the associated socioeconomic status of this practice suggests that the disruption of social networks by the imposition of property lines between individual households acted to limit cultural transmission and collective benefits, such as the sharing of labour, pasture and food. Moreover, IPP seemed to lack the necessary resilience that is required to support the communities and their livestock. Although studies in the QTP are relatively scarce, research suggests that the notion that grassland contracts would address the region's social, economic and environmental problems should be revisited because there is a significant difference in LDN indicator values for IPP and JPP, and evidence of significant degradation in the decades before the 2015 baseline when the UNCCD adopted LDN and SDGs. Evidence suggests that JPP is a more resilient system, capturing the environmental benefits of nomadism and the socioeconomic benefits of land contracts. Given that some of the grasslands are already contracted to individual households, creative JPP property arrangements should be respected. A reconsideration of whether the not-yet-contracted grasslands should be contracted individually rather than jointly, is required if LDN is to be achieved on the QTP by 2030. If the current policy is maintained, research evidence suggests that JPP should be encouraged, and policy makers should seek better ways of ensuring long-term sustainability and that LDN is achieved to maintain the natural capital and associated ecosystem services of the QTP. C1 [Cao, J. J.; Xu, X. Y.] Northwest Normal Univ, Coll Geog & Environm Sci, Lanzhou 730070, Gansu, Peoples R China. [Holden, N. M.] Univ Coll Dublin, Agr & Food Sci Ctr, UCD Sch Biosyst & Food Engn, Dublin 4, Ireland. [Adamowski, J. F.] McGill Univ, Fac Agr & Environm Sci, Dept Bioresource Engn, Quebec City, PQ H9X 3V9, Canada. [Deo, R. C.] Univ Southern Queensland, Inst Agr & Environm, Int Ctr Appl Climate Sci, Sch Agr Computat & Environm Sci, Springfield, Qld 4300, Peoples R China. [Feng, Q.] Chinese Acad Sci, Cold & Arid Reg Environm Engn Res Inst, Alashan Desert Ecohydrol Expt Res Stn, Key Lab Ecohydrol Inland River Basin, Lanzhou 73000, Gansu, Peoples R China. RP Feng, Q (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm Engn Res Inst, Alashan Desert Ecohydrol Expt Res Stn, Key Lab Ecohydrol Inland River Basin, Lanzhou 73000, Gansu, Peoples R China. EM qifeng@lzb.ac.cn TC 16 Z9 17 PD NOV PY 2018 VL 89 BP 192 EP 197 DI 10.1016/j.envsci.2018.08.003 UT WOS:000447557600021 DA 2023-03-23 ER PT J AU Hopping, KA Knapp, AK Dorji, T Klein, JA AF Hopping, Kelly A. Knapp, Alan K. Dorji, Tsechoe Klein, Julia A. TI Warming and land use change concurrently erode ecosystem services in Tibet SO GLOBAL CHANGE BIOLOGY DT Article AB Alpine meadows on the Tibetan Plateau comprise the largest alpine ecosystem in the world and provide critical ecosystem services, including forage production and carbon sequestration, on which people depend from local to global scales. However, the provision of these services may be threatened by climate warming combined with land use policies that are altering if and how pastoralists can continue to graze livestock, the dominant livelihood practice in this region for millennia. We synthesized findings from a climate warming and yak grazing experiment with landscape-level observations in central Tibet to gain insight into the trajectories of change that Tibet's alpine meadows will undergo in response to expected changes in climate and land use. We show that within 5 years, experimental warming drove an alpine community with intact, sedge-dominated turfs into a degraded state. With removal of livestock, consistent with policy intended to reverse degradation, a longer-term shift to a more shrub-dominated community will likely occur. Neither degraded nor shrub meadows produce forage or sequester carbon to the same degree as intact meadows, indicating that climate warming and drying will reduce the ability of Tibet's alpine meadows to provide key ecosystem services, and that livestock reduction policies intended to counteract trajectories of land degradation instead endanger contemporary livelihoods on the Tibetan Plateau. C1 [Hopping, Kelly A.; Knapp, Alan K.; Klein, Julia A.] Colorado State Univ, Grad Degree Program Ecol, Ft Collins, CO 80523 USA. [Hopping, Kelly A.; Klein, Julia A.] Colorado State Univ, Nat Resource Ecol Lab, Ft Collins, CO 80523 USA. [Knapp, Alan K.] Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA. [Dorji, Tsechoe] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Lhasa, Tibet Autonomou, Peoples R China. [Dorji, Tsechoe] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing, Peoples R China. [Klein, Julia A.] Colorado State Univ, Dept Ecosyst Sci & Sustainabil, Ft Collins, CO 80523 USA. RP Hopping, KA (通讯作者)，Boise State Univ, Human Environm Syst, Boise, ID 83725 USA. EM kellyhopping@boisestate.edu TC 59 Z9 67 PD NOV PY 2018 VL 24 IS 11 BP 5534 EP 5548 DI 10.1111/gcb.14417 UT WOS:000447760300040 DA 2023-03-23 ER PT J AU Li, G Zhang, Z Shi, LL Zhou, Y Yang, M Cao, JX Wu, SH Lei, GC AF Li, Gang Zhang, Zhi Shi, Linlu Zhou, Yan Yang, Meng Cao, Jiaxi Wu, Shuhong Lei, Guangchun TI Effects of Different Grazing Intensities on Soil C, N, and P in an Alpine Meadow on the QinghaiTibetan Plateau, China SO INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH DT Article AB Inappropriate grazing management is one of the most common causes of grassland degradation, and thus, an assessment of soil properties under different grazing intensities is critical for understanding its effects on ecosystem nutrient cycling and for formulating appropriate management strategies. However, the responses of certain main elements, including soil carbon, nitrogen, and phosphorus, to grazing in alpine meadow ecosystems remain insufficiently clarified. Here, we measured carbon, nitrogen, and phosphorus contents in the topmost 30 cm of soil in an alpine meadow under three grazing intensities (light, moderate, and heavy) and found clear differences in soil physical and chemical properties among different grazing intensities and soil layers. As grazing intensity increased, soil water content, carbon and nitrogen contents and stocks, and carbon to phosphorus and nitrogen to phosphorus ratios decreased, whereas soil bulk density increased. However, soil phosphorus and carbon to nitrogen ratio remained stable. Our findings highlight the negative impacts of heavy grazing intensity, in terms of soil carbon and nitrogen loss and phosphorus mineralization. Moreover, we emphasize that further related studies are necessary to gain a more comprehensive understanding of the effects of grazing on grassland ecosystems, and thereby provide information for sustainable management practices and eco-compensation policies. C1 [Li, Gang; Zhang, Zhi; Shi, Linlu; Zhou, Yan; Yang, Meng; Wu, Shuhong; Lei, Guangchun] Beijing Forestry Univ, Sch Nat Conservat, Beijing 100083, Peoples R China. [Li, Gang] Fuyang Normal Univ, Sch Biol & Food Engn, Dept Landscape Architecture, Fuyang 236037, Peoples R China. [Zhang, Zhi] Fuzhou Planing Design & Res Inst, Urban Res Ctr, Fuzhou 350108, Peoples R China. [Zhou, Yan] Nanjing Forestry Univ, Coll Biol & Environm, Coinnovat Ctr Sustainable Forestry Southern China, Nanjing 210037, Jiangsu, Peoples R China. [Yang, Meng] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Cao, Jiaxi] Beijing Forestry Univ, Sch Soil & Water Conservat, Beijing 100083, Peoples R China. RP Wu, SH; Lei, GC (通讯作者)，Beijing Forestry Univ, Sch Nat Conservat, Beijing 100083, Peoples R China. EM ligang27@foxmail.com; zhangzqh@126.com; linlu.shi@foxmail.com; zhouyan.eco@foxmail.com; yangmeng@igsnrr.ac.cn; jason.apt@foxmail.com; wshuhong@bjfu.edu.cn; guangchun.lei@foxmail.com TC 20 Z9 23 PD NOV PY 2018 VL 15 IS 11 AR 2584 DI 10.3390/ijerph15112584 UT WOS:000451640500258 DA 2023-03-23 ER PT J AU Wang, C Zhang, ZJ Zhang, H Zhang, B Tang, YX Wu, QB AF Wang, Chao Zhang, Zhengjia Zhang, Hong Zhang, Bo Tang, Yixian Wu, Qingbai TI Active Layer Thickness Retrieval of Qinghai-Tibet Permafrost Using the TerraSAR-X InSAR Technique SO IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING DT Article AB Qinghai-Tibet plateau (QTP) is closely related to global climate change, and it has undergone serious permafrost degradation due to global warming in the last decades. It is crucial to measure the active layer thickness (ALT) for characterizing and monitoring the permafrost degradation of QTP. In this paper, an ALT retrieval model based on ground subsidence derived from synthetic aperture radar interferometry (InSAR), land cover types, and groundwater information is proposed. In particular, the surface subsidence is retrieved using the time-series InSAR technique with TerraSAR-X ST mode images. Moreover, groundwater content models with different land covers are constructed based on multilayered assumptions and in situ data. By taking into account the groundwater content profile and land cover types, the ALT is retrieved from deformation with the full season cycle derived by InSAR technique. The experimental results in Beiluhe indicate that the estimated ALT is consistent with field-measured data. The estimated ALT map shows the difference between the alpine meadow and alpine desert areas, with mean ALT of approximately 1.5 m in alpine meadow area and approximately 3 m in alpine desert area. Our results demonstrate that the InSAR technique with high-resolution SAR images can be of great importance for the study of permafrost environments. C1 [Wang, Chao; Zhang, Zhengjia; Zhang, Hong; Zhang, Bo; Tang, Yixian] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Key Lab Digital Earth Sci, Beijing 100094, Peoples R China. [Wang, Chao] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wu, Qingbai] Chinese Acad Sci, North West Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. RP Wang, C (通讯作者)，Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Key Lab Digital Earth Sci, Beijing 100094, Peoples R China. EM wangchao@radi.ac.cn; zhangzj155@126.co; zhanghong@radi.ac.cn; zhangbo@radi.ac.cn; yxtang@ceode.ac.cn; qbwu@lzb.ac.cn TC 35 Z9 37 PD NOV PY 2018 VL 11 IS 11 BP 4403 EP 4413 DI 10.1109/JSTARS.2018.2873219 UT WOS:000452730100038 DA 2023-03-23 ER PT J AU Wang, YX Sun, Y Wang, ZF Chang, SH Hou, FJ AF Wang, Yingxin Sun, Yi Wang, Zhaofeng Chang, Shenghua Hou, Fujiang TI Grazing management options for restoration of alpine grasslands on the Qinghai-Tibet Plateau SO ECOSPHERE DT Article AB In an attempt to alleviate the problem of grassland degradation on the Qinghai-Tibet Plateau in China, state and local authorities in 2003, initiated the "Retire Livestock and Restore Pastures" ecological engineering program, requiring the use of enclosure fencing to enable grazing exclusion and rotational grazing. A five-year controlled grazing experiment was conducted to determine the effects of this program on (1) sheep live weight gain; and (2a) standing herbage biomass; and (2b) species diversity. Effects of temporal within-year variation in precipitation and temperature on livestock productivity, standing herbage biomass, and species diversity were also investigated. At the end of 5 yr, grazing exclusion showed no significant difference in standing herbage biomass or in species diversity, compared with either continuous grazing or rotational grazing. Rotational grazing at the high stocking rate significantly promoted sheep live weight gain per hectare, but not per sheep; neither standing herbage biomass, nor species diversity, whether under continuous (i.e., traditional) or rotational grazing, showed a significant difference. Under rotational grazing, higher standing herbage biomass and species diversity were required to maintain or increase sheep liveweight, compared with continuous grazing. Temporal distribution of precipitation and temperature had more influence on alpine grassland parameters, than did grazing. Results of this study suggest that herders' local traditional knowledge and expertise might be useful in modifying Government guidelines to fine tune grazing management with the dynamics of the alpine meadow ecosystem, and that it is important to consider equilibrium and non-equilibrium theory in formulating a policy which benefits both herders and grassland. Traditional continuous grazing at a carefully chosen light stocking rate appears to be the most appropriate way to manage livestock and grassland in this region. C1 [Wang, Yingxin; Sun, Yi; Wang, Zhaofeng; Chang, Shenghua; Hou, Fujiang] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs,Coll Pastoral Agr Sci, Lanzhou 730020, Gansu, Peoples R China. RP Hou, FJ (通讯作者)，Lanzhou Univ, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat, Minist Agr & Rural Affairs,Coll Pastoral Agr Sci, Lanzhou 730020, Gansu, Peoples R China. EM cyhoufj@lzu.edu.cn TC 23 Z9 26 PD NOV PY 2018 VL 9 IS 11 AR e02515 DI 10.1002/ecs2.2515 UT WOS:000452621900002 DA 2023-03-23 ER PT J AU Wu, QH Liu, K Song, CQ Wang, JD Ke, LH Ma, RH Zhang, WS Pan, H Deng, XY AF Wu, Qianhan Liu, Kai Song, Chunqiao Wang, Jida Ke, Linghong Ma, Ronghua Zhang, Wensong Pan, Hang Deng, Xinyuan TI Remote Sensing Detection of Vegetation and Landform Damages by Coal Mining on the Tibetan Plateau SO SUSTAINABILITY DT Article AB In order to satisfy the needs of constant economic growth, the pressure to exploit natural resources has been increasing rapidly in China. Particularly with the implementation of the National Western Development Strategies since 1999, more and more mining activities and related infrastructure constructions have been conducted on the Tibetan Plateau (TP). Mining activities are known to have substantial impacts on plant dynamics and hence the water and energy cycles. Identifying mining activities and quantifying their effects on vegetation cover are critical to the monitoring and protection of the pristine TP environment. Thus, this study aims to develop an automated approach that detects the timing of initial mining development and assess the spatial distribution of mining-ruined vegetation. The Breaks for Additive Seasonal and Trend (BFAST) algorithm was used to decompose the signal in the normalized difference vegetation index (NDVI) time series derived from high-frequency MODIS images, and to detect abrupt changes of surface vegetation. Results show that the BFAST algorithm is able to effectively identify abrupt changes in vegetation cover as a result of open-mining development on the studied alpine grassland. The testing study in Muli Town of Qinghai Province shows that the mining development began in 2003 and massive destructions of vegetation cover followed between 2008 and 2012. The integrated use of Landsat imagery and multi-temporal DEMs further reveals detailed areal and volumetric changes in the mining site. This study demonstrates the potential of applying multi-mission satellite datasets to assess large-scale environmental influences from mining development, and will be beneficial to environmental conservation and sustainable use of natural resources in remote regions. C1 [Wu, Qianhan; Liu, Kai; Song, Chunqiao; Ma, Ronghua; Zhang, Wensong; Deng, Xinyuan] Chinese Acad Sci, Nanjing Inst Geog & Limnol, Key Lab Watershed Geog Sci, Nanjing 210008, Jiangsu, Peoples R China. [Wu, Qianhan; Zhang, Wensong] Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing 210044, Jiangsu, Peoples R China. [Wang, Jida] Kansas State Univ, Dept Geog, Manhattan, KS 66506 USA. [Ke, Linghong] Hohai Univ, Sch Earth Sci & Engn, Nanjing 211100, Jiangsu, Peoples R China. [Pan, Hang] Nanjing Univ, Dept Geog Informat Sci, Nanjing 210023, Jiangsu, Peoples R China. [Deng, Xinyuan] Nanjing Univ Informat Sci & Technol, Sch Remote Sensing & Geomat Engn, Nanjing 210044, Jiangsu, Peoples R China. RP Song, CQ (通讯作者)，Chinese Acad Sci, Nanjing Inst Geog & Limnol, Key Lab Watershed Geog Sci, Nanjing 210008, Jiangsu, Peoples R China. EM candyisgreat@foxmail.com; kliu@niglas.ac.cn; cqsong@niglas.ac.cn; jidawang@ksu.edu; kekehere@126.com; rhma@niglas.ac.cn; wensong_z@outlook.com; hangpan_@hotmail.com; alioth711@gmail.com TC 18 Z9 19 PD NOV PY 2018 VL 10 IS 11 AR 3851 DI 10.3390/su10113851 UT WOS:000451531700025 DA 2023-03-23 ER PT J AU Liu, NJ Yang, YP Yao, L Yue, XF AF Liu, Naijing Yang, Yaping Yao, Ling Yue, Xiafang TI A Regionalized Study on the Spatial-Temporal Changes of Grassland Cover in the Three-River Headwaters Region from 2000 to 2016 SO SUSTAINABILITY DT Article AB The Three-River Headwaters Region (TRHR) is located in the interior of the Qinghai-Tibetan Plateau, which is a typical research area in East Asia and is of fragile environment. This paper studied the characteristics of grassland cover changes in the TRHR between 2000 and 2016 using methods of area division (AD) based on natural conditions and tabulate area (TA) dependent on Moderate-resolution Imaging Spectroradiometer (MODIS) 44B product. Further investigations were conducted on some of the typical areas to determine the characteristics of the changes and discuss the driving factors behind these changes. Classification and Regression Trees (CART), Random Forest (RF), Bayesian (BAYE), and Support Vector Machine (SVM) Machine Learning (ML) methods were employed to evaluate the correlation between grassland cover changes and corresponding variables. The overall trend for grassland cover in the TRHR towards recovery that rose 0.91% during the 17-year study period. The results showed that: (1) The change in grassland cover was more divisive in similar elevation and temperature conditions when the precipitation was stronger. The higher the temperature was, the more significant the rise of grassland cover was in comparable elevation and precipitation conditions. (2) There was a distinct decline and high change standard deviation of grassland cover in some divided areas, and strong correlations were found between grassland cover change and aspect, slope, or elevation in these areas. (3) The study methods of AD and TA achieved enhancing performance in interpretation of grassland cover changes in the broad and high elevation variation areas. (4) RF and CART methods showed higher stability and accuracy in application of grassland cover change study in TRHR among the four ML methods utilized in this study. C1 [Liu, Naijing] Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Peoples R China. [Liu, Naijing; Yang, Yaping; Yao, Ling; Yue, Xiafang] Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China. [Yang, Yaping] Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Peoples R China. [Liu, Naijing] Shaanxi Normal Univ, Sch Geog & Tourism, Xian 710119, Shaanxi, Peoples R China. [Liu, Naijing; Yang, Yaping; Yao, Ling; Yue, Xiafang] Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China. [Yang, Yaping] Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Jiangsu, Peoples R China. RP Yang, YP (通讯作者)，Inst Geog Sci & Nat Resources Res, State Key Lab Resources & Environm Informat Syst, Beijing 100101, Peoples R China.; Yang, YP (通讯作者)，Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Jiangsu, Peoples R China. EM Liunj_rw@outlook.com; yangyp@igsnrr.ac.cn; yaoling@lreis.ac.cn; lexf@lreis.ac.cn TC 3 Z9 4 PD OCT PY 2018 VL 10 IS 10 AR 3539 DI 10.3390/su10103539 UT WOS:000448559400181 DA 2023-03-23 ER PT J AU Peng, F Xue, X You, QG Huang, CH Dong, SY Liao, J Duan, HC Tsunekawa, A Wang, T AF Peng Fei Xue Xian You Quangang Huang Cuihua Dong Siyang Liao Jie Duan Hanchen Tsunekawa, Atsushi Wang Tao TI Changes of soil properties regulate the soil organic carbon loss with grassland degradation on the Qinghai-Tibet Plateau SO ECOLOGICAL INDICATORS DT Article AB Grassland in the Qinghai-Tibet Plateau (QTP) provides tremendous carbon (C) sinks and is the important ground for grazing. Grassland degradation, the loss of plant coverage and the emergence of sand activities, results in substantial reduction in soil organic carbon (SOC). To demonstrate the pattern of SOC loss and to elucidate underlying mechanisms, vegetation, soil microclimate, soil properties and respiration of grasslands with different degradation severity over the QTP were investigated. The survey and laboratory data were analyzed by three structural equation modeling (SEM) analyses, which based on three conceptual understandings. The black box model (M1) directly related the abiotic and biotic factors to SOC without consideration of any mechanisms. The biological understanding model (M2) developed the structure of SEM mainly considering ecological processes that regulate the soil SOC. The overall model (M3) developed the SEM structure with the inclusion of both physical and biological processes. Soil moisture (theta), the above and the below-ground plant productivity, and SOC significantly decreased while soil temperature (T-soil) maintained with the development of land degradation. All the three models successfully fitted the data with R-2 about 0.50. Significant pathways from latent variables to SOC were only observed from soil microclimate and soil properties in the Ml. In the M2, three mechanisms can explain the SOC change. The decrease in theta and the consequent adverse effect on soil respiration suggest suppressed C output through microbial decomposition, thus lead to the less SOC loss. The decline in aboveground net primary productivity (ANPP) resulted from a decrease in coverage or due to the change in relative abundance of sedge, forbs, and grass directly or indirectly reduced the C input, and finally lead to the 40-50% loss in SOC. In the M3, only the change in soil properties can explain the SOC reduction. Our results suggest that changes in soil abiotic factors like soil bulk density and pH are the primary factors control the SOC change with land degradation. C1 [Peng Fei; Xue Xian; You Quangang; Huang Cuihua; Dong Siyang; Liao Jie; Duan Hanchen; Wang Tao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou, Gansu, Peoples R China. [Peng Fei; Tsunekawa, Atsushi] Tottori Univ, Int Platform Dryland Res & Educ, Tottori, Japan. [Peng Fei; Tsunekawa, Atsushi] Tottori Univ, Arid Land Res Ctr, Tottori, Japan. [Xue Xian] Univ Oklahoma, Dept Microbial & Plant, Norman, OK 73019 USA. RP Peng, F; Xue, X (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou, Gansu, Peoples R China. EM pengfei@lzb.ac.cn; xianxue@lzb.ac.cn TC 46 Z9 51 PD OCT PY 2018 VL 93 BP 572 EP 580 DI 10.1016/j.ecolind.2018.05.047 UT WOS:000452692600058 DA 2023-03-23 ER PT J AU Wang, Y Lehnert, LW Holzapfel, M Schultz, R Heberling, G Gorzen, E Meyer, H Seeber, E Pinkert, S Ritz, M Fu, Y Ansorge, H Bendix, J Seifert, B Miehe, G Long, RJ Yang, YP Wesche, K AF Wang, Yun Lehnert, Lukas W. Holzapfel, Maika Schultz, Roland Heberling, Gwendolyn Goerzen, Eugen Meyer, Hanna Seeber, Elke Pinkert, Stefan Ritz, Markus Fu, Yao Ansorge, Hermann Bendix, Joerg Seifert, Bernhard Miehe, Georg Long, Rui-Jun Yang, Yong-Ping Wesche, Karsten TI Multiple indicators yield diverging results on grazing degradation and climate controls across Tibetan pastures SO ECOLOGICAL INDICATORS DT Article AB Understanding the impacts of livestock grazing is crucial to rangeland management and conservation. Numerous indicators have been employed to detect differences caused by grazing, while case studies suggest that effects differ among individual indicator systems. Across Tibetan pastures that have evolved with long grazing histories and harbour high levels of biodiversity, we tested: (I) whether commonly used grazing indicators differ in their sensitivity to grazing and environmental conditions, and (2) the relative importance of grazing and abiotic factors in controlling effects on indicators. Our sampling covered 18 sites within two main grassland types (steppe and meadow). We compared species compositions among communities of plants, small mammals and ants, as well as overall soil chemical conditions and field hyperspectral reflectance data using multivariate analyses between two qualitative levels of grazing intensity (heavy vs. light). Using univariate Generalized Linear Models, we explored the effects of grazing intensity, grassland type and their interaction on the richness and abundance of biotic groups as well as values of key soil and hyperspectral indices. The major environmental factors tested included temperature, precipitation, elevation, relief, exposure and inclination. Few of the indicators differed under relatively heavy grazing, including reductions in vegetation cover, soil organic carbon, total nitrogen concentration and two hyperspectral indices. Indicator groups differed both quantitatively and qualitatively with respect to grazing and climate impacts. Grazing effects were evident in the moist Kobresia meadows of eastern Tibet, while environmental controls dominated in alpine steppes of the drier western part of the plateau. Grazing effects on indicators thus depended on local precipitation conditions. Multivariate species compositions were affected by abiotic factors in all biotic indicator groups: precipitation was the most influential abiotic factor affecting plant species composition, overall soil nutrients and hyper spectral data, while elevation and temperature influenced ant and small mammal communities in terms of richness and species composition. Our results do not support the notion that local increases in relative grazing intensity have strong effects on the species richness of key biotic indicator groups across all Tibetan pastures. Reliable assessments of grazing effects thus require both multiple appropriate indicators and careful calibration to account for local climate and topographic conditions. Differences between principal grassland types must be acknowledged for future grassland conservation and management. C1 [Wang, Yun; Holzapfel, Maika; Schultz, Roland; Ritz, Markus; Ansorge, Hermann; Seifert, Bernhard; Wesche, Karsten] Senckenberg Museum Nat Hist Gorlitz, POB 300154, D-02806 Gorlitz, Germany. [Wang, Yun] Martin Luther Univ Halle Wittenberg, Dept Geobot & Bot Garden, Kirchtor 1, D-06108 Halle, Saale, Germany. [Lehnert, Lukas W.; Holzapfel, Maika; Meyer, Hanna; Bendix, Joerg; Miehe, Georg] Philipps Univ Marburg, Fac Geog, Deutschhausstr 10, D-35032 Marburg, Germany. [Heberling, Gwendolyn] Gesell Freilandokol & Nat Chutzplanung MbH, Stuthagen 25, D-24113 Molfsee, Germany. [Goerzen, Eugen] Christian Albrechts Univ Kiel, Dept Landscape Ecol, Olshausenstr 75, D-24118 Kiel, Germany. [Seeber, Elke] Univ Greifswald, Dept Expt Plant Ecol, Inst Bot & Landscape Ecol, Soldmannstr 15, D-17489 Greifswald, Germany. [Pinkert, Stefan] Philipps Univ Marburg, Fac Biol, Karl von Frisch Str 8, D-35043 Marburg, Germany. [Fu, Yao; Yang, Yong-Ping] Chinese Acad Sci, Kunming Inst Bot, Lanhei Rd 132, Kunming 650201, Yunnan, Peoples R China. [Long, Rui-Jun] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, 768 Jiayuguan West Rd, Lanzhou 730020, Gansu, Peoples R China. [Wesche, Karsten] German Ctr Integrat Biodivers Res iDiv, Deutsch Pl 5e, D-04103 Leipzig, Germany. [Wesche, Karsten] Tech Univ Dresden, Int Inst Zittau, Markt 23, D-02763 Zittau, Germany. RP Wang, Y (通讯作者)，Senckenberg Museum Nat Hist Gorlitz, POB 300154, D-02806 Gorlitz, Germany. EM yun.wang@senckenberg.de TC 15 Z9 16 PD OCT PY 2018 VL 93 BP 1199 EP 1208 DI 10.1016/j.ecolind.2018.06.021 UT WOS:000452692600117 DA 2023-03-23 ER PT J AU Yan, YL Ganjurjav, H Hu, GZ Liang, Y Li, Y He, SC Danjiu, LB Yang, J Gao, QZ AF Yan, Yulong Ganjurjav, Hasbagan Hu, Guozheng Liang, Yan Li, Yu He, Shicheng Danjiu, Luobu Yang, Jie Gao, Qingzhu TI Nitrogen deposition induced significant increase of N2O emissions in an dry alpine meadow on the central Qinghai-Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Atmospheric concentrations of nitrous oxide (N2O) have increased over the last 150 years due to human activities. Soils are important source of N2O where its production is largely regulated by biological processes. Nitrogen (N) deposition can alter the processes of autotrophic nitrification and denitrification, thus affecting the rate and direction of the soil N2O exchange with the atmosphere. It is obvious that atmospheric N deposition has influenced a dry alpine meadow in the Qinghai-Tibetan Plateau (QTP). Therefore, we investigated the effects of N deposition on the annual N2O emissions in an alpine meadow of the QTP. The N2O flux was measured for 2 years using static chambers and gas chromatography methods at four treatments (NO, background level; N7, add 7 kg N ha(-1) yr(-1); N2O, add 20 kg N ha(-1) yr(-1); N40, add 40 kg N ha(-1) yr(-1)). We found that high N deposition increased the N2O flux, not only in the growing season but also in winter and the spring thaw period. The average annual N2O fluxes at N0 and N40 plots were 3.1 and 6.1 mu g m(-2) h(-1), respectively. Compared with N0, the average annual N2O fluxes increased at N7, N2O, and N40 plots by 13.7%, 47.6%, and 98.7%, respectively, the N2O fluxes in N40 plots increased by 113.6%, 41.6%, and 78.7% during the growing season, winter and spring thaw period, respectively. The emission of N2O during the growing season, winter and spring thaw period accounted for 63.2%, 29.9% and 6.9% of annual total emission of N2O, respectively. The N2O flux correlated significantly with air temperature, soil temperature, soil water content, total nitrogen, total organic carbon, and soil NH4+-N content in the alpine meadow. C1 [Yan, Yulong; Yang, Jie] Inner Mongolia Univ, Sch Ecol & Environm, Hohhot 010021, Peoples R China. [Yan, Yulong; Ganjurjav, Hasbagan; Hu, Guozheng; Liang, Yan; Gao, Qingzhu] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Li, Yu] Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China. [He, Shicheng; Danjiu, Luobu] Nagqu Grassland Stn, Nagqu 852100, Tibet Autonomou, Peoples R China. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM gaoqingzhu@caas.cn TC 32 Z9 40 PD OCT 1 PY 2018 VL 265 BP 45 EP 53 DI 10.1016/j.agee.2018.05.031 UT WOS:000443664900007 DA 2023-03-23 ER PT J AU Zong, N Geng, SB Duan, C Shi, PL Chai, X Zhang, XZ AF Zong, Ning Geng, Shoubao Duan, Cheng Shi, Peili Chai, Xi Zhang, Xianzhou TI The effects of warming and nitrogen addition on ecosystem respiration in a Tibetan alpine meadow: The significance of winter warming SO ECOLOGY AND EVOLUTION DT Article AB In recent decades, global warming has become an indisputable fact on the Tibetan Plateau. Alpine ecosystems are very sensitive to global warming, and the impact may depend on the degree of atmospheric nitrogen (N) deposition. The previous studies have paid more attention to year-round warming, but the effect of winter warming has been unstudied. In this study, a manipulative experiment was conducted, consisting of warming and N addition. It was carried out since 2010 in an alpine meadow, and three types of warming treatments were set up: no warming (NW), year-round (YW), and winter warming (WW). Warming significantly increased air and soil temperature, but decreased soil moisture. Under no N addition, YW showed significantly decreased ecosystem respiration (Reco) in 2012, and WW decreased Reco in 2014. Under N addition, neither YW nor WW had significant effects on Reco, indicating that N addition compensated the negative effect of warming on Reco. Annually, YW and WW decreased ecosystem carbon (C) emissions, and the extent of the reduction was even larger under WW. Under no N addition, both YW and WW significantly decreased aboveground biomass. Moreover, especially under no N, YW and WW significantly decreased soil inorganic N. WW also had negative effects on soil microbial biomass C. Structure equation modeling showed that soil moisture was the most important factors controlling Reco, and soil inorganic N content and microbial biomass C could explain 46.6% and 16.8% of the variation of Reco. The findings indicate that soil property changes under warming had substantial effects on ecosystem C efflux. The inhibitory effects of winter warming on ecosystem C efflux were mainly attributed to the decline of soil N and microbial biomass. Thus, the effects of winter warming on ecosystem C emissions in this semiarid alpine meadow are not as serious as expected and largely depend on N deposition. C1 [Zong, Ning; Geng, Shoubao; Duan, Cheng; Shi, Peili; Chai, Xi; Zhang, Xianzhou] Chinese Acad Sci, Lhasa Natl Ecol Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China. [Geng, Shoubao; Duan, Cheng; Shi, Peili; Chai, Xi] Univ Chinese Acad Sci, Beijing, Peoples R China. RP Zong, N; Shi, PL (通讯作者)，Chinese Acad Sci, Lhasa Natl Ecol Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China. EM zongning@igsnrr.ac.cn; shipl@igsnrr.ac.cn TC 18 Z9 20 PD OCT PY 2018 VL 8 IS 20 BP 10113 EP 10125 DI 10.1002/ece3.4484 UT WOS:000449529800013 DA 2023-03-23 ER PT J AU Luo, DL Jin, HJ He, RX Wang, XF Muskett, RR Marchenko, SS Romanovsky, VE AF Luo, D. L. Jin, H. J. He, R. X. Wang, X. F. Muskett, R. R. Marchenko, S. S. Romanovsky, V. E. TI Characteristics of Water-Heat Exchanges and Inconsistent Surface Temperature Changes at an Elevational Permafrost Site on the Qinghai-Tibet Plateau SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES DT Article AB Increase of surface temperatures has long been recognized as an unequivocal response to radiative forcing and one of the most important implications for global warming. However, it remains unclear whether the variation of ground surface temperature (GST) and soil temperatures is consistent with simultaneous changes of the near-surface air and land (or skin) surface temperatures (T-a and LST). In this study, a seven-year continuous observation of GST, T-a, and surface water and heat exchange was carried out at an elevational permafrost site at Chalaping, northeastern Qinghai-Tibet Plateau. Results showed a distinct retarding of warming on the ground surface and subsurface under the presence of dense vegetation and moist peat substrates. Mean annual T-a and LST increased at noteworthy rates of 0.22 and 0.32 degrees C/a, respectively, while mean annual GST increased only at a rate of 0.057 degrees C/a. No obvious trends were detected for the four radiation budgets except the soil heat flux (G), which significantly increased at a rate of 0.29 W.m(-2).a(-1), presumably inducing the melting of ground ice and resulted in much higher moisture content through the summers of 2015 and 2016 than preceding years and subsequent 2017 at the depths between 80 and 120 cm. However, no noticeable immediate variations of soil temperatures occurred owing to the large latent heat effect (thermal inertia) and the extending zero-curtain period. We suggest that a better protected eco-environment, particularly the surface vegetation, helps preserving the underlying permafrost, and thus to mitigates the potential degradation of elevational permafrost on the Qinghai-Tibet Plateau. C1 [Luo, D. L.; Jin, H. J.; He, R. X.; Marchenko, S. S.] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou, Gansu, Peoples R China. [Jin, H. J.] Harbin Inst Technol, Sch Civil Engn, Harbin, Heilongjiang, Peoples R China. [Wang, X. F.] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Remote Sensing Gansu Prov, Heihe Remote Sensing Expt Res Stn, Lanzhou, Gansu, Peoples R China. [Muskett, R. R.; Marchenko, S. S.; Romanovsky, V. E.] Univ Alaska Fairbanks, Inst Geophys, Fairbanks, AK 99775 USA. RP Luo, DL (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou, Gansu, Peoples R China. EM luodongliang@lzb.ac.cn TC 32 Z9 37 PD SEP 27 PY 2018 VL 123 IS 18 BP 10404 EP 10422 DI 10.1029/2018JD028298 UT WOS:000447807300023 DA 2023-03-23 ER PT J AU Zhou, Y Jiao, SW Li, NN Grace, J Yang, M Lu, C Geng, XM Zhu, XW Zhang, L Lei, GC AF Zhou, Yan Jiao, Shengwu Li, Nana Grace, John Yang, Meng Lu, Cai Geng, Xuemeng Zhu, Xinwei Zhang, Li Lei, Guangchun TI Impact of plateau pikas (Ochotona curzoniae) on soil properties and nitrous oxide fluxes on the Qinghai-Tibetan Plateau SO PLOS ONE DT Article AB This paper demonstrates the impact of an endemic fossorial animal, plateau pika (Ochotona curzoniae), on soil properties and N2O flux at the Zoige Wetland. Pika burrow and control sites without disturbance by pika were selected to measure the soil water content, bulk density, soil organic matter (SOM), NH4-N content and NO3-N content in August 2012. N2O fluxes were measured with static opaque chambers at these sites in June and August 2012. Pika burrowing altered soil aeration by transferring deeper soil to the surface and by constructing underground burrows, which significantly increased bulk density, and reduced soil water content, SOM and NH4-N content at 0-10 cm and 10-20 cm soil depth. N2O flux had a significant correlation with bulk density, SOM and NH4-N content. Pika burrowing significantly influenced N2O flux by increasing N2O flux at the control site from near zero to 0.063 +/- 0.011 mg m(-2) h(-1). Our findings described how pika burrowing influences the soil traits and significantly increases the principal greenhouse gas N2O emission. As plateau pika was commonly considered as a pest, our findings give a novel clue to effectively manage populations of plateau pika on the Qinghai-Tibet Plateau from the perspective of greenhouse gas emission. C1 [Zhou, Yan] Nanjing Forestry Univ, Coll Biol & Environm, Southern Modern Forestry Collaborat Innovat Ctr, Nanjing, Jiangsu, Peoples R China. [Zhou, Yan; Jiao, Shengwu; Li, Nana; Yang, Meng; Lu, Cai; Geng, Xuemeng; Lei, Guangchun] Beijing Forestry Univ, Sch Nat Conservat, Beijing, Peoples R China. [Jiao, Shengwu] Chinese Acad Forestry, Res Inst Subtrop Forestry, Fuyang, Peoples R China. [Grace, John] Univ Edinburgh, Sch Geosci, Edinburgh, Midlothian, Scotland. [Zhu, Xinwei; Zhang, Li] Aba Prefecture Res Inst Forestry Sci & Technol, Aba, Peoples R China. RP Lei, GC (通讯作者)，Beijing Forestry Univ, Sch Nat Conservat, Beijing, Peoples R China. EM leiguangchunbjfu@gmail.com TC 5 Z9 5 PD SEP 27 PY 2018 VL 13 IS 9 AR e0203691 DI 10.1371/journal.pone.0203691 UT WOS:000445907400014 DA 2023-03-23 ER PT J AU Fang, QQ Wang, GQ Liu, TX Xue, BL A, YL AF Fang, Qingqing Wang, Guoqiang Liu, Tingxi Xue, Bao-Lin A, Yinglan TI Controls of carbon flux in a semi-arid grassland ecosystem experiencing wetland loss: Vegetation patterns and environmental variables SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Inner Mongolia, China, contains the world's largest grassland ecosystem. This has many areas of wetland, which provide important ecological services, especially carbon sequestration in the semi-arid terrestrial ecosystems. However, the area of wetland has decreased sharply in the past two decades. This study examined ways to recognize and extract wetland from grassland to determine the difference among net ecosystem exchange (NEE), gross primary production (GPP) and ecosystem respiration (k(eco)) between wetland and grassland and to evaluate the influence of wetland loss on carbon sequestration in the grassland. The eddy covariance (EC) flux technique was coupled with the Vegetation Photosynthesis and Respiration Model (VPRM) to upscale the spatial patterns of carbon flux. The results showed that the region was a carbon source in 2016, probably caused by overharvesting and degradation of forests. The value of the NEE (average: 6.63 +/- 3.50 g C m(-2) d(-2)) in grassland was apparently higher than that in wetland (average: 0.86 +/- 1.69 g C M-2 d(-1)), which suggested that the capability of carbon sequestration in wetland was still stronger than that in grassland even in carbon loss condition. The results showed a positive relationship between aboveground biomass (AGB) and ground-based daily GPP or Redo for both wetland and grassland and a negative relationship between AGB and NEE. The ground-based daily NEE was also significantly related to soil water content (SWC) but showed no relationship with daily precipitation (PRE), which suggested that SWC was a more important impact factor than precipitation on CO2 flux exchange in the study area. The change between wetland and grassland did not influence the positive relationship between AGB or SWC and CO2 flux. Our study provides a new way to determine the spatial CO2 flux exchange and its controlling factors (environmental variables and vegetation patterns) and to successfully analyze its differences in wetland and grassland. C1 [Fang, Qingqing; Wang, Guoqiang; Xue, Bao-Lin; A, Yinglan] Beijing Normal Univ, Coll Water Sci, Xinjiekouwai St 19, Beijing 100875, Peoples R China. [Liu, Tingxi] Inner Mongolia Agr Univ, Coll Water Conservancy & Civil Engn, Hohhot 010018, Inner Mongolia, Peoples R China. RP Wang, GQ; Xue, BL (通讯作者)，Beijing Normal Univ, Coll Water Sci, Xinjiekouwai St 19, Beijing 100875, Peoples R China. EM wanggq@bnu.edu.cn; xuebl@bnu.edu.cn TC 46 Z9 50 PD SEP 15 PY 2018 VL 259 BP 196 EP 210 DI 10.1016/j.agrformet.2018.05.002 UT WOS:000437064400018 DA 2023-03-23 ER PT J AU He, HD Li, HQ Zhu, JB Wei, YX Zhang, FW Yang, YS Li, YN AF He, Huidan Li, Hongqin Zhu, Jingbin Wei, Yaxi Zhang, Fawei Yang, Yongsheng Li, Yingnian TI The asymptotic response of soil water holding capacity along restoration duration of artificial grasslands from degraded alpine meadows in the Three River Sources, Qinghai-Tibetan Plateau, China SO ECOLOGICAL RESEARCH DT Article AB The artificial grassland is one of the most important practices to restore degraded alpine meadow. However, it is still not clear how the water conservation capacity respond along the restoration duration. We conducted the experiment for soil water holding capacity along the restoration duration of 0year (extremely degradation, CK), 2years (2Y), 4years (4Y), 6years (6Y) and 12years (12Y), as well as light degradation (CK1). Along the restoration duration, aboveground biomass, soil porosity, soil organic carbon, and total nitrogen increased while soil bulk density decreased. The saturated soil water holding capacity increased and plateaued at 6Y restoration duration. The total porosity and soil bulk density played a predominated role in the soil water-holding capacity variations. Our results revealed that the asymptotic response of soil water-holding capacity to restoration duration in artificial grasslands and indicated that 6-year restoration would be appropriate in rehabilitating water conservation for extremely degraded alpine meadow. C1 [He, Huidan; Li, Hongqin; Zhu, Jingbin; Wei, Yaxi; Zhang, Fawei; Yang, Yongsheng; Li, Yingnian] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xinning Rd 23, Xining 810001, Qinghai, Peoples R China. [He, Huidan; Zhu, Jingbin; Wei, Yaxi] Univ Chinese Acad Sci, Beijing, Peoples R China. RP Li, YN (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xinning Rd 23, Xining 810001, Qinghai, Peoples R China. EM ynli@nwipb.cas.cn TC 4 Z9 8 PD SEP PY 2018 VL 33 IS 5 BP 1001 EP 1010 DI 10.1007/s11284-018-1608-y UT WOS:000443688900018 DA 2023-03-23 ER PT J AU Luo, ZH Wu, WC Yu, XJ Song, QM Yang, J Wu, JH Zhang, HJ AF Luo, Zhaohui Wu, Wenchen Yu, Xijun Song, Qingmei Yang, Jian Wu, Jiahui Zhang, Hengjun TI Variation of Net Primary Production and Its Correlation with Climate Change and Anthropogenic Activities over the Tibetan Plateau SO REMOTE SENSING DT Article AB Grasslands in the Tibetan Plateau are claimed to be sensitive and vulnerable to climate change and anthropogenic activities. Quantifying the impacts of climate change and anthropogenic activities on grassland growth is an essential step for developing sustainable grassland ecosystem management strategies under the background of climate change and increasing anthropogenic activities occurring in the plateau. Net primary productivity (NPP) is one of the key components in the carbon cycle of terrestrial ecosystems, and can serve an important role in the assessment of vegetation growth. In this study, a modified Carnegie-Ames-Stanford Approach (CASA) model, which considers remote sensing information for the estimation of the water stress coefficient and time-lag effects of climatic factors on NPP simulation, was applied to simulate NPP in the Tibetan Plateau from 2001 to 2015. Then, the spatiotemporal variations of NPP and its correlation with climatic factors and anthropogenic activities were analyzed. The results showed that the mean values of NPP were 0.18 kg. C.m(-2).a(-1) and 0.16 kg.C.m(-2).a(-1) for for the original CASA model and modified CASA model, respectively. The modified CASA model performed well in estimating NPP compared with field-observed data, with root mean square error (RMSE) and mean absolute error (MAE) of 0.13 kg. C.m(-2).a(-1) and 0.10 kg. C.m(-2).a(-1), respectively. Relative RMSE and MAE decreased by 45.8% and 44.4%, respectively, compared to the original CASA model. The variation of NPP showed gradients decreasing from southeast to northwest spatially, and displayed an overall decreasing trend for the study area temporally, with a mean value of -0.02 x 10 -2 kg.C.m(-2).a(-1) due to climate change and increasing anthropogenic activities (i.e., land use and land cover change). Generally, 54% and 89% of the total pixels displayed a negative relationship between NPP and mean annual temperature, as well as annual cumulative precipitation, respectively, with average valuesof -0.0003 (kg. C.m(-2).a(-1))/degrees C and -0.254 (kg. C.m(-2).a(-1))/mm for mean annual temperature and temperature and annual cumulative precipitation, respectively. Additionally, about 68% of the total pixels displayed a positive relationship between annual cumulative solar radiation and NPP, with a mean value of 0.038 (g. C.m(-2).a(-1))/(MJ m(-2) ). Anthropogenic activities had a negative effect on NPP variation, and it was larger than that of climate change, implying that human intervention plays a critical role in mitigating the degenerating ecosystem. In terms of human intervention, ecological destruction has a significantly negative effect on the NPP trend, and the absolute value was larger than that of ecological restoration, which has a significantly positive effect on NPP the trend. Our results indicate that ecological destruction should be paid more attention, and ecological restoration should be conducted to mitigate the overall decreasing trend of NPP in the plateau. C1 [Luo, Zhaohui; Wu, Wenchen; Yu, Xijun; Song, Qingmei; Yang, Jian; Wu, Jiahui; Zhang, Hengjun] Minist Environm Protect, South China Inst Environm Sci, Guangzhou 510655, Guangdong, Peoples R China. [Luo, Zhaohui; Yu, Xijun] State Environm Protect Key Lab Urban Ecol Simulat, Guangzhou 510655, Guangdong, Peoples R China. RP Zhang, HJ (通讯作者)，Minist Environm Protect, South China Inst Environm Sci, Guangzhou 510655, Guangdong, Peoples R China. EM huizhaoluo@163.com; wenchen_w@sina.com; xij_yu@163.com; song_qinmei@126.com; yangj_scies@sina.cn; jiah_wu@sina.com; csufttdl@126.com TC 40 Z9 43 PD SEP PY 2018 VL 10 IS 9 AR 1352 DI 10.3390/rs10091352 UT WOS:000449993800032 DA 2023-03-23 ER PT J AU Ma, L Yao, ZS Zheng, XH Zhang, H Wang, K Zhu, B Wang, R Zhang, W Liu, CY AF Ma, Lei Yao, Zhisheng Zheng, Xunhua Zhang, Han Wang, Kai Zhu, Bo Wang, Rui Zhang, Wei Liu, Chunyan TI Increasing grassland degradation stimulates the non-growing season CO2 emissions from an alpine meadow on the Qinghai-Tibetan Plateau SO ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH DT Article AB The alpine meadow ecosystem is one of the major vegetation biomes on the Qinghai-Tibetan Plateau, which hold substantial quantities of soil organic carbon. Pronounced grassland degradations (induced by overgrazing/climate change and further exacerbated by the subterranean rodent activities) that have widely occurred in this ecosystem may significantly alter the non-growing season carbon turnover processes such as carbon dioxide (CO2) efflux, but little is known about how the non-growing season CO2 emissions respond to the degradation (particularly the exacerbated degradations by plateau zokor), as most previous studies have focused primarily on the growing season. In this study, the effects of four degradation levels (i.e., the healthy meadow (HM), degraded patches (DP), 2-year-old zokor mounds (ZM2), and current-year zokor mounds (ZM1)) on CO2 emissions and corresponding environmental and agronomic variables were investigated over the two non-growing seasons under contrasting climatic conditions (a normal season in 2013-2014 and a warm and humid season in 2014-2015). The temporal variation in the non-growing season CO2 emissions was mainly regulated by soil temperature, while increasing degradation levels reduced the temperature sensitivity of CO2 emissions due to a reduction in soil water content. The cumulative CO2 emissions across the non-growing season were 587-1283kg Cha(-1) for all degradation levels, which varied significantly (p<0.05) interannually. The degradation of alpine meadows significantly (p<0.05) reduced the vegetation cover and aboveground net primary productivity as well as the belowground biomass, which are typically thought to decrease soil CO2 emissions. However, the non-growing season CO2 emissions for the degraded meadow, weighted by the areal extent of the DP, ZM2, and ZM1, were estimated to be 641-1280kg Cha(-1), which was significantly higher (p<0.05) as compared with the HM in the warm and humid season of 2014-2015 but not in the normal season of 2013-2014. Additionally, grassland degradation substantially increased the productivity-scaled non-growing season CO2 emissions, which showed an exponential trend with increasing degradation levels. These results suggest that there is a strong connection between grassland degradation and soil carbon loss, e.g., in the form of CO2 release, pointing to the urgent need to manage degraded grassland restoration that contributes to climate change mitigation. C1 [Ma, Lei; Yao, Zhisheng; Zheng, Xunhua; Zhang, Han; Wang, Kai; Wang, Rui; Zhang, Wei; Liu, Chunyan] Chinese Acad Sci, Inst Atmospher Phys, State Key Lab Atmospher Boundary Layer Phys & Atm, Beijing 100029, Peoples R China. [Ma, Lei; Zheng, Xunhua] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Han] Nanjing Univ Informat Sci & Technol, Nanjing 210044, Jiangsu, Peoples R China. [Zhu, Bo] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolvement & Regulat, Chengdu 610041, Sichuan, Peoples R China. RP Yao, ZS (通讯作者)，Chinese Acad Sci, Inst Atmospher Phys, State Key Lab Atmospher Boundary Layer Phys & Atm, Beijing 100029, Peoples R China. EM zhishengyao@mail.iap.ac.cn TC 21 Z9 23 PD SEP PY 2018 VL 25 IS 26 BP 26576 EP 26591 DI 10.1007/s11356-018-2724-5 UT WOS:000443329100082 DA 2023-03-23 ER PT J AU Wang, J Zhang, CY Yang, H Mou, CX Mo, L Luo, P AF Wang, Jun Zhang, Chunyan Yang, Hao Mou, Chengxiang Mo, Li Luo, Peng TI Plant community ecological strategy assembly response to yak grazing in an alpine meadow on the eastern Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Predicting the impact of grazing on vegetation structure, and thus on ecosystem services, is one of the main technical bottlenecks in alpine grassland conservation and management. However, past researches based on the fixed, discrete, and qualitative indicators limited our understanding for the effect of grazing on plant community assembly. Research based on the quantitative competitor, stress tolerator, and ruderal (CSR) theory increases the possibilities for analyzing this ecological process. To test the hypothesis that the dominant plant strategy in alpine meadow plant community will shift from S-selection to R-selection with increased grazing intensity, the plant community CSR strategy assemblies among the cold-seasonal grazing meadows along a gradient of grazing intensity were studied on the eastern Tibetan Plateau. The dominant strategy concentrated in the S-selected corner under the low grazing intensity, which provided a direct evidence to the environmental filters in the alpine area, and suggested that species of strong S-selection should dominate the undisturbed alpine grassland plant community. The C-selection of dominant strategies increased (R-2 = 0.431, p = 0.004), and the extent of S-selection decreased with greater grazing intensity; however, the R-selection of them only slightly increased under intermediate grazing intensity and finally decreased under high grazing intensity, reflecting a selective grazing disturbance combined with localized enrichment of soil that can provide microsites for the establishment of competitors. The strong C-selected species may dominate the plant community on the eastern Tibetan Plateau in place of S-selected and R-selected species, if the grazing intensity is continually high. C1 [Wang, Jun; Yang, Hao; Mou, Chengxiang; Mo, Li; Luo, Peng] Chinese Acad Sci, Chengdu Inst Biol, CAS Key Lab Mt Ecol Restorat & Bioresource Utiliz, Chengdu 610041, Sichuan, Peoples R China. [Wang, Jun; Yang, Hao; Mou, Chengxiang; Mo, Li; Luo, Peng] Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat & Biodivers Conservat Key Lab Sichu, Chengdu 610041, Sichuan, Peoples R China. [Wang, Jun] China West Normal Univ, Inst Environm Sci, Nanchong 637009, Sichuan, Peoples R China. [Wang, Jun; Yang, Hao; Mou, Chengxiang; Mo, Li; Luo, Peng] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Jun] China West Normal Univ, Coll Environm Sci & Engn, Nanchong 637009, Sichuan, Peoples R China. [Zhang, Chunyan] China West Normal Univ, Coll Life Sci, Nanchong 637009, Sichuan, Peoples R China. RP Luo, P (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, CAS Key Lab Mt Ecol Restorat & Bioresource Utiliz, Chengdu 610041, Sichuan, Peoples R China.; Luo, P (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat & Biodivers Conservat Key Lab Sichu, Chengdu 610041, Sichuan, Peoples R China.; Luo, P (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM luopeng@cib.ac.cn TC 20 Z9 24 PD SEP PY 2018 VL 29 IS 9 BP 2920 EP 2931 DI 10.1002/ldr.3050 UT WOS:000444078100015 DA 2023-03-23 ER PT J AU Xiao, H Peng, Z Xu, CL Zhang, DG Chai, JL Pan, TT Yu, XJ AF Xiao, Hong Peng, Zhen Xu, Chang Lin Zhang, De Gang Chai, Jin Long Pan, Tao Tao Yu, Xiao Jun TI Yak and Tibetan sheep trampling inhibit reproductive and photosynthetic traits of Medicago ruthenica var. inschanica SO ENVIRONMENTAL MONITORING AND ASSESSMENT DT Article AB Livestock grazing affects grassland stability, resilience, and productivity owing to trampling, foraging, and excretion. Over time, trampling influences a wide range of grassland components and can have lasting effects. Trampling helps maintain grassland health but may also cause its degradation. In a field experiment over two growing seasons, we simulated yak and sheep trampling at different intensities and investigated their effects on the reproductive and photosynthetic characteristics of Medicago ruthenica vac inschanica in a Tianzhu alpine meadow in Gansu Province, China. Our results show that simulated trampling inhibited the asexual and sexual reproduction and growth of M. ruthenica. The root surface area, root volume, root biomass, pod length, pod number per unit area, number of seeds per pod, thousand-seed weight, and seed yield were significantly reduced under simulated trampling in the upper 30 cm of soil (P < 0.05) but were not reduced in the deeper soil layers (>30 cm). Light trampling by both yak and Tibetan sheep promoted photosynthesis, while heavy trampling by both species inhibited photosynthesis. Yak trampling inhibited photosynthesis more than Tibetan sheep trampling, and overall, the adverse effects of yak trampling on asexual and sexual reproduction and growth of M ruthenica were greater than those of Tibetan sheep trampling. Thus, the effect of yak trampling is greater than the effect of trampling by Tibetan sheep, where the different trampling intensities of yak and Tibetan sheep can result in direct but varied influences on grasslands, potentially leading to grassland differentiation. C1 [Xiao, Hong; Peng, Zhen; Xu, Chang Lin; Zhang, De Gang; Chai, Jin Long; Pan, Tao Tao; Yu, Xiao Jun] Gansu Agr Univ, Coll Grassland Sci, Lanzhou 730070, Gansu, Peoples R China. [Xiao, Hong; Peng, Zhen; Xu, Chang Lin; Zhang, De Gang; Chai, Jin Long; Pan, Tao Tao; Yu, Xiao Jun] Minist Educ, Key Lab Grassland Ecosyst, Lanzhou 730070, Gansu, Peoples R China. [Xiao, Hong; Peng, Zhen; Xu, Chang Lin; Zhang, De Gang; Chai, Jin Long; Pan, Tao Tao; Yu, Xiao Jun] Sino US Ctr Grassland Ecosyst Sustainabil, Lanzhou 730070, Gansu, Peoples R China. RP Yu, XJ (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Lanzhou 730070, Gansu, Peoples R China. EM 1181827215@qq.com; 1148022412@qq.com; xucl@gsau.edu.cn; zhangdg@gsau.edu.cn; 1373629791@qq.com; 1574690603@qq.com; yuxj@gsau.edu.cn TC 16 Z9 19 PD SEP PY 2018 VL 190 IS 9 AR 507 DI 10.1007/s10661-018-6896-8 UT WOS:000441252100001 DA 2023-03-23 ER PT J AU Zhen, L Du, BZ Wei, YJ Xiao, Y Sheng, WP AF Zhen, Lin Du, Bingzhen Wei, Yunjie Xiao, Yu Sheng, Wenping TI Assessing the effects of ecological restoration approaches in the alpine rangelands of the Qinghai-Tibetan Plateau SO ENVIRONMENTAL RESEARCH LETTERS DT Article AB Ecological restoration has increased in prominence since the last century as an active way to reverse ecosystem deterioration derived from human interventions. The goal of this study was to assess the impact of restoration approaches on ecological and economic conditions of typical regions in the Qinghai-Tibetan Plateau. Data were collected using structured questionnaires delivered to 195 herders living in areas with average elevation above 3773 m. Land use maps, MODIS images, and government statistics were also used for the study. It was found that local herders have adopted five major approaches, i.e. enclosure, grazing prohibition, enclosure + deratization, enclosure + deratization + grass seeding, and enclosure + deratization + crop-forage cultivation + warm sheds, to ensure success of the restoration programs initiated by the government. The results show that vegetation coverage, especially for high and very high coverage grasslands, increased across the study sites and across approaches used, with a high grassland recovery rate observed in the areas where either grazing is prohibited or grassland management was dominated by integration approaches. Furthermore, households who employed integrated approaches tended to have more animals to rear, higher capability of resisting risks, and higher income than those who did not. These findings imply that balanced ecological and economic development is possible when appropriate management approaches are adopted. However, evaluation and monitoring of grassland conditions are needed to readjust restoration policy and associated approaches in a timely manner. C1 [Zhen, Lin; Du, Bingzhen; Wei, Yunjie; Xiao, Yu; Sheng, Wenping] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Zhen, Lin; Wei, Yunjie; Xiao, Yu] Univ Chinese Acad Sci, Sch Resource & Environm, Beijing 100049, Peoples R China. [Zhen, Lin] Minist Land & Resources, Key Lab Resources & Environm Carrying Capac Asses, Beijing 100812, Peoples R China. RP Zhen, L (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China.; Zhen, L (通讯作者)，Univ Chinese Acad Sci, Sch Resource & Environm, Beijing 100049, Peoples R China.; Zhen, L (通讯作者)，Minist Land & Resources, Key Lab Resources & Environm Carrying Capac Asses, Beijing 100812, Peoples R China. EM zhenl@igsnrr.ac.cn TC 12 Z9 15 PD SEP PY 2018 VL 13 IS 9 AR 095005 DI 10.1088/1748-9326/aada51 UT WOS:000444072600001 DA 2023-03-23 ER PT J AU Zong, N Chai, X Shi, PL Yang, XC AF Zong, Ning Chai, Xi Shi, Pei-Li Yang, Xiao-Cheng TI Effects of Warming and Nitrogen Addition on Plant Photosynthate Partitioning in an Alpine Meadow on the Tibetan Plateau SO JOURNAL OF PLANT GROWTH REGULATION DT Article AB Quantifying plant carbon (C) allocation among different pools is critical for understanding and predicting how C turnover responds to global climate change in terrestrial ecosystems. A field experiment with increasing warming and nitrogen (N) was established to investigate interactive effects on plant C allocation in alpine meadows. Open-top chambers (OTCs) were used to simulate warming. In OTCs, daytime air and soil temperature at 5 cm depth increased by 2.0 and 1.6 A degrees C, respectively, compared with ambient conditions, but soil moisture at 5 cm depth decreased by 4.95% (v/v) from 2012 to 2014. Warming reduced aboveground biomass by 38, 36, and 43% in 2012, 2013, and 2014, respectively, and increased belowground biomass by 64% and 29% in 2013 and 2014, respectively, and the root-to-shoot ratio was significantly increased. Specifically, warming increased the proportion of plant roots in the deep layers (10-20 cm). Both N addition and its combination with warming substantially enhanced belowground biomass. Pulse-labeling experiments for C-13 revealed that warming reduced the translocation of assimilated C to shoots by 8.8% (38.7% in warming, and 47.5% in the control [CK]), and increased the allocation to root by 12.2% (55.5% in warming, and 43.3% in CK) after 28 days labeling. However, N addition increased the proportion of assimilated C allocated to shoots by 6.5% (54.0% in N addition, and 47.5% in CK), whereas warming combined with N addition reduced this proportion by 10.9%. A decline in soil water content in the surface layer may be the main cause of plants allocating more newly fixed photosynthate to roots. Therefore, plants promoted root growth to draw water from deeper soil layers (10-20 cm). We concluded that climate warming will change the allocation patterns of plant photosynthates by affecting soil water availability, whereas N addition will increase plant photosynthates aboveground in alpine meadows and thus will significantly affect C turnover under future climate change scenarios. C1 [Zong, Ning; Chai, Xi; Shi, Pei-Li] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, 11A Datun Rd, Beijing 100101, Peoples R China. [Chai, Xi; Shi, Pei-Li] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Yang, Xiao-Cheng] Chengdu Univ Technol, Coll Mat & Chem & Chem Engn, 1 Dongsanlu, Chengdu 610059, Sichuan, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, 11A Datun Rd, Beijing 100101, Peoples R China.; Shi, PL (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China.; Yang, XC (通讯作者)，Chengdu Univ Technol, Coll Mat & Chem & Chem Engn, 1 Dongsanlu, Chengdu 610059, Sichuan, Peoples R China. EM shipl@igsnrr.ac.cn; yxc39@163.com TC 14 Z9 16 PD SEP PY 2018 VL 37 IS 3 BP 803 EP 812 DI 10.1007/s00344-017-9775-6 UT WOS:000439443100009 DA 2023-03-23 ER PT J AU Li, L Tietze, DT Fritz, A Lu, Z Burgi, M Storch, I AF Li, Li Tietze, Dieter Thomas Fritz, Andreas Lu, Zhi Burgi, Matthias Storch, Ilse TI Rewilding cultural landscape potentially puts both endemism at risk: A Tibetan Plateau case study SO BIOLOGICAL CONSERVATION DT Article AB Ecological restoration is becoming a primary strategy to increase provisions of ecosystem services and reverse biodiversity losses. In cultural landscapes undergoing land use extensification, rewilding has been proposed as a viable approach to reverse biodiversity loss through reducing human impacts. The world's largest ecological restoration campaign is taking place on the eastern Qinghai-Tibetan Plateau (QTP) to combat grassland degradation and enhance the upper stream region's water retention capacity. However, little is known about whether the large-scale rewilding also benefits the unique bird assemblage of the eastern QTP. Our study aims to make science-based conservation recommendations for the Tibetan avifauna by detecting their diversity and endemism distribution patterns at the local scale. In the breeding seasons of 2014 and 2015, we carried out bird surveys and conducted a habitat mapping using three Unmanned Aerial Vehicles (UAVs). We developed a comprehensive set of 2D and 3D habitat feature parameters from the high-resolution (10 cm level) UAV-derived images. Meanwhile, we employed the participatory GIS approach to acquire farm-scale human land-use data. Our results indicate that the distributions of avian diversity, endemism and abundance are not congruent across the eastern QTP, which calls for the conservation of different habitat types. Vertical and horizontal habitat heterogeneity maintain the local bird diversity with anthropogenic elements significantly enriching the overall bird abundance. Degraded pastures provided key habitats for two highly abundant endemic passerines the White-rumped Snowfinch Ortychosmuthus taczanowskii and the Ground Tit Pseudopodoces humilis. At the landscape scale, historical human-nature interactions between Tibetan nomads and the alpine environment formed the landscapes patchy vegetation structure. Our results reveal that the Tibetan cultural landscape maintains the structural heterogeneity needed to achieve multiple bird conservation objectives on the eastern QTP. Restoring the cultural landscape to a 'natural' tall-grass or dense-shrubland state of high water-retention capacity may result in the loss of both high-abundance avian communities and endemic species diversity. Our empirical study also indicated that rewilding abandoned agricultural landscape will not necessarily lead to a desired conservation outcome, especially when the requirements of habitat specialists and endemics are not taken into account. Moreover, ecological restoration projects should evaluate the divergences between their ecosystem service and biodiversity objectives. C1 [Li, Li; Storch, Ilse] Univ Freiburg, Wildlife Ecol & Management, D-79106 Freiburg, Germany. [Tietze, Dieter Thomas] Nat Hist Museum Basel, Augustinergasse 2, CH-4001 Basel, Switzerland. [Fritz, Andreas] Univ Freiburg, Remote Sensing & Land Informat Syst, D-79106 Freiburg, Germany. [Lu, Zhi] Peking Univ, Sch Life Sci, Beijing 100871, Peoples R China. [Burgi, Matthias] Swiss Fed Res Inst WSL, Res Unit Landscape Dynam, CH-8903 Birmensdorf, Switzerland. RP Li, L (通讯作者)，Univ Freiburg, Wildlife Ecol & Management, D-79106 Freiburg, Germany. EM li.li@wildlife.uni-freiburg.de TC 11 Z9 11 PD AUG PY 2018 VL 224 BP 75 EP 86 DI 10.1016/j.biocon.2018.05.008 UT WOS:000439537600009 DA 2023-03-23 ER PT J AU Zhao, HW Guo, K Yang, Y Liu, CC Zhao, LQ Qiao, XG Hou, DJ Gao, CG AF Zhao, Haiwei Guo, Ke Yang, Yao Liu, Changcheng Zhao, Liqing Qiao, Xianguo Hou, Dongjie Gao, Chenguang TI Stipa steppes in scantily explored regions of the Tibetan Plateau: classification, community characteristics and climatic distribution patterns SO JOURNAL OF PLANT ECOLOGY DT Article AB Aims As a unique geographical unit of the earth, the Tibetan Plateau is extensively covered by various Stipa communities. However, their vegetation features have not been reported systematically till now, especially in some scantily explored regions. In this study, we endeavor to reveal the community types, quantitative characteristics and climatic distribution patterns of Stipa steppes in these areas based on primary releves obtained from fieldwork. Methods We collected a total of 223 plots in 79 study sites in the Changthang Plateau and the Yarlung Zangbo Valley, ranging from 79 degrees E to 91 degrees E. The categories of Stipa formations were identified according to the classification scheme in Vegetation of China and then verified by Nonmetric Multidimensional Scaling. We performed detrended correspondence analysis and detrended canonical correspondence analysis to hunt for the alteration of Stipa communities along the precipitation gradient. Quantitative characteristics including species richness, coverage, biomass as well as importance values (IV) of dominant species were calculated and visualized, respectively. Important Findings Stipa steppes in scantily explored regions of the Tibetan Plateau are classified into 11 formations but major formations are rather limited in number. Formation (form.) Stipa purpurea is the most widespread Stipa assemblages not only in scantily explored regions but also across the whole Tibetan Plateau. The characteristics of Stipa communities, including coverage, species richness, productivity and IV of dominant species, demonstrate the features of typical alpine steppes on the Tibetan Plateau. Precipitation proves to be the prime climatic factor controlling the distribution patterns of Stipa assemblages. Form. Stipa subsessiliflora var. basiplumosa and form. Stipa glareosa normally distribute in arid habitats, but rainfall for the former is of greater variance. Form. Stipa roborowskyi and form. Stipa capillacea favor moderately moist environment. Form. Stipa purpurea and form. Stipa roborowskyi can tolerate a fairly broad range of precipitation. C1 [Zhao, Haiwei; Guo, Ke; Yang, Yao; Liu, Changcheng; Qiao, Xianguo; Hou, Dongjie; Gao, Chenguang] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, 20 Nanxincun, Beijing 100093, Peoples R China. [Zhao, Haiwei; Qiao, Xianguo; Hou, Dongjie; Gao, Chenguang] Univ Chinese Acad Sci, Coll Life Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China. [Zhao, Liqing] Inner Mongolia Univ, Sch Life Sci, 235 Daxuexi Rd, Hohhot 010021, Inner Mongolia, Peoples R China. RP Guo, K (通讯作者)，Chinese Acad Sci, Inst Bot, 20 Nanxincun, Beijing 100093, Peoples R China. EM guoke@ibcas.ac.cn TC 3 Z9 5 PD AUG PY 2018 VL 11 IS 4 BP 585 EP 594 DI 10.1093/jpe/rtx029 UT WOS:000433291100009 DA 2023-03-23 ER PT J AU Ma, XL Liu, GM Wu, XD Smoak, JM Ye, LL Xu, HY Zhao, L Ding, YJ AF Ma, Xiaoliang Liu, Guimin Wu, Xiaodong Smoak, Joseph M. Ye, Linlin Xu, Haiyan Zhao, Lin Ding, Yongjian TI Influence of land cover on riverine dissolved organic carbon concentrations and export in the Three Rivers Headwater Region of the Qinghai-Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The Qinghai-Tibet-an plateau (QTP) stores a large amount of soil organic carbon and is the headwater region for several large rivers in Asia. Therefore, it is important to understand the influence of environmental factors on river water quality and the dissolved organic carbon (DOC) export in this region. We examined the water physico-chemical characteristics, DOC concentrations and export rates of 7 rivers under typical land cover types in the Three Rivers Headwater Region during August 2016. The results showed that the highest DOC concentrations were recorded in the rivers within the catchment of alpine wet meadow and meadow. These same rivers had the lowest total suspended solids (TSS) concentrations. The rivers within steppe and desert had the lowest DOC concentrations and highest TSS concentrations. The discharge rates and catchment areas were negatively correlated with DOC concentrations. The SLIVA(254) values were significantly negatively correlated with DOC concentrations. The results suggest that the vegetation degradation, which may represent permafrost degradation, can lead to a decrease in DOC concentration, but increasing DOC export and soil erosion. In addition, some of the exported DOC will rapidly decompose in the river, and therefore affect the regional carbon cycle, as well as the water quality in the source water of many large Asian rivers. (C) 2018 Elsevier B.V. All rights reserved. C1 [Ma, Xiaoliang; Liu, Guimin; Xu, Haiyan] Lanzhou Jiaotong Univ, Sch Environm & Municipal Engn, 88 West Anning Rd, Lanzhou 730070, Gansu, Peoples R China. [Ma, Xiaoliang; Wu, Xiaodong; Zhao, Lin; Ding, Yongjian] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, Lanzhou 730000, Gansu, Peoples R China. [Smoak, Joseph M.] Univ S Florida, Environm Sci, St Petersburg, FL 33701 USA. [Ye, Linlin] Nantong Univ, Sch Geog Sci, Nantong 226000, Peoples R China. [Ding, Yongjian] Chinese Acad Sci, Key Lab Ecohydrol River Basin Sci, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. [Ding, Yongjian] Univ Chinese Acad Sci, 19 A Yuquan Rd, Beijing 100049, Peoples R China. RP Liu, GM (通讯作者)，Lanzhou Jiaotong Univ, Sch Environm & Municipal Engn, 88 West Anning Rd, Lanzhou 730070, Gansu, Peoples R China.; Wu, XD (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. EM liuguimin@mail.lzjtu.cn; wuxd@lzb.ac.cn TC 17 Z9 23 PD JUL 15 PY 2018 VL 630 BP 314 EP 322 DI 10.1016/j.scitotenv.2018.02.152 UT WOS:000432467700033 DA 2023-03-23 ER PT J AU Dong, SK Li, Y Zhao, ZZ Li, YY Liu, SL Zhou, HK Dong, QM Li, S Gao, XX Shen, H Xu, YD Han, YH Zhang, J Yang, MY AF Dong, Shikui Li, Yu Zhao, Zhenzhen Li, Yuanyuan Liu, Shiliang Zhou, Huakun Dong, Quanming Li, Shuai Gao, Xiaoxia Shen, Hao Xu, Yudan Han, Yuhui Zhang, Jing Yang, Mingyue TI Land Degradation Enriches Soil delta C-13 in Alpine Steppe and Soil delta N-15 in Alpine Desert by Changing Plant and Soil Features on Qinghai Tibetan Plateau SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL DT Article AB Estimation of natural isotopic abundances can integrate across biogeochemical processes affecting the carbon and nitrogen dynamics in an ecosystem. Here, we investigated the natural isotopic abundances (delta C-13 and delta N-15) of the soil in healthy and degraded alpine ecosystems, including alpine meadow, alpine steppe, and alpine desert on the Qinghai-Tibetan Plateau (QTP). We also examined the effects of plant factors and soil chemical and physical factors on the soil delta C-13 and delta N-15 in these alpine ecosystems of the QTP. The results indicated that the soil delta C-13 and delta N-15 varied significantly with the grassland type, the land degradation, and soil depth. The C4-plant dominated alpine desert was much higher in the soil delta C-13 and delta N-15 than the C3-plant dominated alpine meadow and alpine steppe. Along the soil depth of 0 to 30 cm, the delta C-13 and delta N-15 were enriched in all types of the alpine ecosystems. The land degradation lowered the plant cover, aboveground plant biomass, soil organic carbon (SOC) and soil total nitrogen (TN) in all alpine ecosystems. Land degradation enriched the soil delta C-13 in the alpine steppe and the soil delta N-15 in alpine desert by changing their interactions with the plant and soil features. C1 [Dong, Shikui; Li, Yu; Zhao, Zhenzhen; Liu, Shiliang; Li, Shuai; Gao, Xiaoxia; Shen, Hao; Xu, Yudan; Han, Yuhui; Zhang, Jing; Yang, Mingyue] Beijing Normal Univ, Sch Environ, Beijing 100875, Peoples R China. [Li, Yuanyuan] Minist Environm Protect, Policy Res Ctr Environ & Econ, Beijing 100029, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining 810008, Qinghai, Peoples R China. [Dong, Quanming] Qinghai Univ, Qinghai Acad Anim Husb & Vet Sci, Xining 810003, Qinghai, Peoples R China. RP Dong, SK; Li, Y (通讯作者)，Beijing Normal Univ, Sch Environ, Beijing 100875, Peoples R China. EM dsk03037@bnu.edu.cn; liyu4227@163.com TC 2 Z9 2 PD JUL-AUG PY 2018 VL 82 IS 4 BP 960 EP 968 DI 10.2136/sssaj2018.01.0017 UT WOS:000446664900023 DA 2023-03-23 ER PT J AU Li, CX Wulf, H Schmid, B He, JS Schaepman, ME AF Li, Chengxiu Wulf, Hendrik Schmid, Bernhard He, Jin-Sheng Schaepman, Michael E. TI Estimating Plant Traits of Alpine Grasslands on the Qinghai-Tibetan Plateau Using Remote Sensing SO IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING DT Article AB Mapping plants traits on theQinghai-Tibetan Plateau grassland is important for understanding ecosystem functions and how plants respond to global change. Detailed trait maps for the complete Qinghai-Tibetan Plateau are missing. Here, we addressed this issue by combining Sentinel-2 and Landsat-8 multispectral satellite data with field measurements to map and compare plant traits of meadow and steppe communities across the complete Qinghai-Tibetan Plateau. We measured in-situ plant-level traits of CHLorophyll content (CHL), specific plant area (SPA = plant area / plant dry mass), and plant dry matter content (PDMC = plant dry mass / fresh mass). We hypothesized that plant-level traits of SPA and PDMC are close to community-weighted means (CWMs) of specific leaf area (SLA) and leaf dry matter content (LDMC) because leaves represent the largest fraction of above-ground biomass in the Qinghai-Tibetan Plateau grasslands. Despite vastly different measurement methods, we found that the remotely sensed traits (SPA and PDMC) correlated with literature-derived leaf traits of CWMs of SLA and LDMC. Both remotely sensed and field-measured results showed that alpine meadow plants reveal a wider range and higher averages of CHL and SPA but lower PDMC compared with alpine steppe plants. These trait differences between vegetation types indicate faster growth of alpine meadow and higher resilience to harsh conditions of alpine steppe, representing differences in adaptation strategies to environmental conditions. Our study demonstrates that remote sensing can be used to estimate plant traits in alpine grasslands with potential applications to retrieve functional diversity and correlated ecosystem functions in future studies. C1 [Li, Chengxiu; Wulf, Hendrik; Schmid, Bernhard; Schaepman, Michael E.] Univ Zurich, Dept Geog, Remote Sensing Labs, CH-8057 Zurich, Switzerland. [He, Jin-Sheng] Peking Univ, Dept Ecol, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. RP Li, CX (通讯作者)，Univ Zurich, Dept Geog, Remote Sensing Labs, CH-8057 Zurich, Switzerland. EM chengxiu.li@geo.uzh.ch; hendrik.wulf@geo.uzh.ch; bernhard.schmid@uzh.ch; jshe@pku.edu.cn; michael.schaepman@geo.uzh.ch TC 17 Z9 18 PD JUL PY 2018 VL 11 IS 7 BP 2263 EP 2275 DI 10.1109/JSTARS.2018.2824901 UT WOS:000440035600010 DA 2023-03-23 ER PT J AU Sun, Y Schleuss, PM Pausch, J Xu, XL Kuzyakov, Y AF Sun, Yue Schleuss, Per-Marten Pausch, Johanna Xu, Xingliang Kuzyakov, Yakov TI Nitrogen pools and cycles in Tibetan Kobresia pastures depending on grazing SO BIOLOGY AND FERTILITY OF SOILS DT Article AB Kobresia grasslands on the Tibetan Plateau comprise the world's largest pastoral alpine ecosystem. Overgrazing-driven degradation strongly proceeded on this vulnerable grassland, but the mechanisms behind are still unclear. Plants must balance the costs of releasing C to soil against the benefits of accelerated microbial nutrient mineralization, which increases their availability for root uptake. To achieve the effect of grazing on this C-N exchange mechanism, a (NH4)-N-15 (+) field labeling experiment was implemented at grazed and ungrazed sites, with additional treatments of clipping and shading to reduce belowground C input by manipulating photosynthesis. Grazing reduced gross N mineralization rates by 18.7%, similar to shading and clipping. This indicates that shoot removal by grazing decreased belowground C input, thereby suppressing microbial N mining and overall soil N availability. Nevertheless, NH4 (+) uptake rate by plants at the grazed site was 1.4 times higher than at the ungrazed site, because plants increased N acquisition to meet the high N demands of shoot regrowth (compensatory growth: grazed > ungrazed). To enable efficient N uptake and regrowth, Kobresia plants have developed specific traits (i.e., efficient above-belowground interactions). These traits reflect important mechanisms of resilience and ecosystem stability under long-term moderate grazing in an N-limited environment. However, excessive (over)grazing might imbalance such C-N exchange and amplify plant N limitation, hampering productivity and pasture recovery over the long term. In this context, a reduction in grazing pressure provides a sustainable way to maintain soil fertility, C sequestration, efficient nutrient recycling, and overall ecosystem stability. C1 [Sun, Yue; Kuzyakov, Yakov] Univ Goettingen, Dept Agr Soil Sci, D-37077 Gottingen, Germany. [Schleuss, Per-Marten] Univ Bayreuth, Dept Soil Ecol, BayCEER, D-95447 Bayreuth, Germany. [Pausch, Johanna] Univ Bayreuth, Dept Agroecol, BayCEER, D-95447 Bayreuth, Germany. [Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, D-37077 Gottingen, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan, Russia. RP Xu, XL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. EM xuxingl@hotmail.com TC 28 Z9 30 PD JUL PY 2018 VL 54 IS 5 BP 569 EP 581 DI 10.1007/s00374-018-1280-y UT WOS:000434829400002 DA 2023-03-23 ER PT J AU Chen, J Luo, YQ Xia, JY Zhou, XH Niu, SL Shelton, S Guo, W Liu, SX Dai, WT Cao, JJ AF Chen, Ji Luo, Yiqi Xia, Jianyang Zhou, Xuhui Niu, Shuli Shelton, Shelby Guo, Wei Liu, Suixin Dai, Wenting Cao, Junji TI Divergent responses of ecosystem respiration components to livestock exclusion on the Qinghai Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Grazing exclusion (GE) is an effective method for protecting degraded grasslands, and it can profoundly affect ecosystem carbon (C) cycles. Ecosystem respiration (ER), which includes both autotrophic and heterotrophic respiration (HR), accounts for the largest land-to-atmosphere C fluxes. How ER responds to GE is still unclear, however, and to investigate this, a controlled GE experiment was conducted at a meadow grassland near Qinghai Lake, China. Animal exclusion enhanced ER and aboveground plant respiration (R-agb) by 10.5% and 40.1%, respectively, but it suppressed soil respiration by 12.4% and HR by 17.6%. Positive responses of ER and R-agb were linked to increased aboveground biomass, particularly graminoids biomass. Negative responses of soil respiration and HR were associated with GE-induced changes in microbial biomass C and nitrogen. These results show that grassland responded in complex ways to GE and that ER and its components were regulated by both abiotic and biotic factors. Moreover, the divergent responses of respiration components have important implications for models of terrestrial C cycles and climate under enhanced human activities and changes in land use. C1 [Chen, Ji; Liu, Suixin; Dai, Wenting; Cao, Junji] Chinese Acad Sci, SKLLQG, Inst Earth Environm, Xian 710061, Shaanxi, Peoples R China. [Chen, Ji; Liu, Suixin; Dai, Wenting; Cao, Junji] Chinese Acad Sci, Key Lab Aerosol Chem & Phys, Inst Earth Environm, Xian 710061, Shaanxi, Peoples R China. [Chen, Ji] Northwestern Polytech Univ, Key Lab Space Biosci & Biotechnol, Ctr Ecol & Environm Sci, Xian 710072, Shaanxi, Peoples R China. [Luo, Yiqi] Tsinghua Univ, Dept Earth Syst Sci, Beijing 100084, Peoples R China. [Luo, Yiqi] No Arizona Univ, Ctr Ecosyst Sci & Soc, Flagstaff, AZ 86011 USA. [Xia, Jianyang; Zhou, Xuhui] East China Normal Univ, Sch Ecol & Environm Sci, Tiantong Natl Field Observat Stn Forest Ecosyst, Shanghai 200062, Peoples R China. [Xia, Jianyang; Zhou, Xuhui] East China Normal Univ, Ctr Global Change & Ecol Forecasting, Shanghai 200062, Peoples R China. [Niu, Shuli] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Shelton, Shelby] Univ Colorado, Dept Emergency Med, Denver, CO 80045 USA. [Guo, Wei] Xi An Jiao Tong Univ, Dept Earth & Environm Sci, Xian 710049, Shaanxi, Peoples R China. [Cao, Junji] Xi An Jiao Tong Univ, Inst Global Environm Change, Xian 710049, Shaanxi, Peoples R China. RP Chen, J (通讯作者)，Northwestern Polytech Univ, Ctr Ecol & Environm Sci, West Youyi Rd, Xian 710072, Shaanxi, Peoples R China.; Cao, JJ (通讯作者)，Chinese Acad Sci, Inst Earth Environm, 97 Yanxiang Rd, Xian 710061, Shaanxi, Peoples R China. EM chenji@ieecas.cn; cao@loess.llqg.ac.cn TC 14 Z9 15 PD JUN PY 2018 VL 29 IS 6 BP 1726 EP 1737 DI 10.1002/ldr.2981 UT WOS:000435278900018 DA 2023-03-23 ER PT J AU Li, LH Zhang, YL Liu, LS Wu, JS Li, SC Zhang, HY Zhang, BH Ding, MJ Wang, ZF Paudel, B AF Li, Lanhui Zhang, Yili Liu, Linshan Wu, Jianshuang Li, Shicheng Zhang, Haiyan Zhang, Binghua Ding, Mingjun Wang, Zhaofeng Paudel, Basanta TI Current challenges in distinguishing climatic and anthropogenic contributions to alpine grassland variation on the Tibetan Plateau SO ECOLOGY AND EVOLUTION DT Review AB Quantifying the impact of climate change and human activities on grassland dynamics is an essential step for developing sustainable grassland ecosystem management strategies. However, the direction and magnitude of climate change and human activities in driving alpine grassland dynamic over the Tibetan Plateau remain under debates. Here, we systematically reviewed the relevant studies on the methods, main conclusions, and causes for the inconsistency in distinguishing the respective contribution of climatic and anthropogenic forces to alpine grassland dynamic. Both manipulative experiments and traditional statistical analysis show that climate warming increase biomass in alpine meadows and decrease in alpine steppes, while both alpine steppes and meadows benefit from an increase in precipitation or soil moisture. Overgrazing is a major factor for the degradation of alpine grassland in local areas with high level of human activity intensity. However, across the entire Tibetan Plateau and its subregions, four views characterize the remaining controversies: alpine grassland changes are primarily due to (1) climatic force, (2) nonclimatic force, (3) combination of anthropogenic and climatic force, or (4) alternation of anthropogenic and climatic force. Furthermore, these views also show spatial inconsistencies. Differences on the source and quality of remote sensing products, the structure and parameter of models, and overlooking the spatiotemporal heterogeneity of human activity intensity contribute to current disagreements. In this review, we highlight the necessity for taking the spatiotemporal heterogeneity of human activity intensity into account in the models of attribution assessment, and the importance for accurate validation of climatic and anthropogenic contribution to alpine grassland variation at multiple scales for future studies. C1 [Li, Lanhui; Zhang, Yili; Liu, Linshan; Zhang, Haiyan; Zhang, Binghua; Wang, Zhaofeng; Paudel, Basanta] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing, Peoples R China. [Li, Lanhui; Zhang, Yili; Zhang, Haiyan; Zhang, Binghua] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhang, Yili] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing, Peoples R China. [Wu, Jianshuang] Free Univ Berlin, Inst Biol, Biodivers Theoret Ecol, Berlin, Germany. [Li, Shicheng] China Univ Geosci, Sch Publ Adm, Wuhan, Hubei, Peoples R China. [Ding, Mingjun] Jiangxi Normal Univ, Nanchang, Jiangxi, Peoples R China. RP Zhang, YL; Liu, LS (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing, Peoples R China. EM zhangyl@igsnrr.ac.cn; liuls@igsnrr.ac.cn TC 49 Z9 54 PD JUN PY 2018 VL 8 IS 11 BP 5949 EP 5963 DI 10.1002/ece3.4099 UT WOS:000435776600063 DA 2023-03-23 ER PT J AU Li, XL Gao, J Zhang, J AF Li, Xilai Gao, Jay Zhang, Jing TI A topographic perspective on the distribution of degraded meadows and their changes on the Qinghai-Tibet Plateau, West China SO LAND DEGRADATION & DEVELOPMENT DT Article AB Meadow degradation is a serious environmental and ecological problem on the Qinghai-Tibet Plateau. A topographic perspective on the changes in the severity of meadow degradation can yield vital information on the effectiveness of rehabilitative measures and efforts. This study aims to reveal the topographic properties of degraded meadows in relation to those of the general terrain in the Qingzhen Township of southern Qinghai Province of China comparatively. After degraded meadows were mapped at 3 levels of severity from satellite images recorded in 1995, 2001, and 2015, the topographic features of degraded meadows, intact meadows, and the changes between them were explored in a geographic information system. It is found that degraded meadows increased by 528.07ha (15.21%) during 1995-2001, but lost 1,495.67ha (37.40%) during 2001-2015. The most and the least severely degraded meadows experienced a loss whereas moderately degraded meadows increased, with most changes taking place between adjoining levels of severity. Topographically, the changes in degradation severity bear a consistent relationship with elevation and slope gradient in that more severely degraded meadows are located at a lower elevation of a gentler slope. The changes from degraded to intact meadows take place at a lower elevation on a gentler slope, an outcome likely attributable to the rehabilitative efforts. C1 [Li, Xilai] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. [Gao, Jay] Univ Auckland, Sch Environm, New Zealand Private Bag 92019, Auckland, New Zealand. [Li, Xilai; Zhang, Jing] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Qinghai, Peoples R China. [Li, Xilai] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat Ecol Cold Area Qinghai Prov, Xining 81008, Qinghai, Peoples R China. RP Gao, J (通讯作者)，Univ Auckland, Sch Environm, New Zealand Private Bag 92019, Auckland, New Zealand. EM jg.gao@auckland.ac.nz TC 9 Z9 15 PD JUN PY 2018 VL 29 IS 6 BP 1574 EP 1582 DI 10.1002/ldr.2952 UT WOS:000435278900004 DA 2023-03-23 ER PT J AU Liu, HW Wang, L Zhang, FQ Li, QY Zhou, HK AF Liu, Hanwu Wang, Lin Zhang, Fengqin Li, Qiuying Zhou, Huakun TI ANALYZING THE CAUSES OF ALPINE MEADOW DEGRADATION AND THE EFFICIENCY OF RESTORATION STRATEGIES THROUGH A MATHEMATICAL MODELLING EXERCISE SO MATHEMATICAL BIOSCIENCES AND ENGINEERING DT Article AB As an important ecosystem, alpine meadow in China has been degraded severely over the past few decades. In order to restore degraded alpine meadows efficiently, the underlying causes of alpine meadow degradation should be identified and the efficiency of restoration strategies should be evaluated. For this purpose, a mathematical modeling exercise is carried out in this paper. Our mathematical analysis shows that the increasing of raptor mortality and the decreasing of livestock mortality (or the increasing of the rate at which livestock increases by consuming forage grass) are the major causes of alpine meadow degradation. We find that controlling the amount of livestock according to the grass yield or ecological migration, together with protecting raptor, is an effective strategy to restore degraded alpine meadows; while meliorating vegetation and controlling rodent population with rodenticide are conducive to restoring degraded alpine meadows. Our analysis also suggests that providing supplementary food to livestock and building greenhouse shelters to protect livestock in winter may contribute to alpine meadow degradation. C1 [Liu, Hanwu; Zhang, Fengqin; Li, Qiuying] Yuncheng Univ, Dept Appl Math, Yuncheng 044000, Shanxi, Peoples R China. [Liu, Hanwu; Wang, Lin] Univ New Brunswick, Dept Math & Stat, Fredericton, NB E3B 5A3, Canada. [Zhou, Huakun] Chinese Acad Sci, North West Plateau Inst Biol, Key Lab Ecol Restorat Cold Reg Qinghai Prov, Xining 810001, Qinghai, Peoples R China. RP Wang, L (通讯作者)，Univ New Brunswick, Dept Math & Stat, Fredericton, NB E3B 5A3, Canada. EM liuhanwu-china@163.com; lwang2@unb.ca; zhafq@263.net; liqy-123@163.com; qinghaihk5151@sina.com TC 1 Z9 1 PD JUN PY 2018 VL 15 IS 3 BP 765 EP 773 DI 10.3934/mbe.2018034 UT WOS:000423049800009 DA 2023-03-23 ER PT J AU Zhao, ZZ Dong, SK Jiang, XM Zhao, JB Liu, SL Yang, MY Han, YH Sha, W AF Zhao, Zhenzhen Dong, Shikui Jiang, Xiaoman Zhao, Jinbo Liu, Shiliang Yang, Mingyue Han, Yuhui Sha, Wei TI Are land use and short time climate change effective on soil carbon compositions and their relationships with soil properties in alpine grassland ecosystems on Qinghai-Tibetan Plateau? SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Fencing and grass plantation are two key interventions to preserve the degraded grassland on the Qinghai-Tibetan Plateau (QTP). Climate warming and N deposition have substantially affected the alpine grassland ecosystems. However, molecular composition of soil organic carbon (SOC), the indicator of degradation of SOC, and its responses to climate change are still largely unclear. In this study, we conducted the experiments in three types of land use on the QTP: alpine meadow (AM), alpine steppe (AS), and cultivated grassland (CG) under 2 degrees C climatic warming, 5 levels of nitrogen deposition rates at 8, 24, 40, 56, and 72 kg N ha(-1) year(-1), as well as a combination of climatic warming and N deposition (8 kg N ha(-1) year(-1)). Our findings indicate that all three types of land use were dominated by O-alkyl carbon. The alkyl/O-alkyl ratio, aromaticity and hydrophobicity index of the CG were larger than those of the AM and AS, and this difference was generally stable under different treatments. Most of the SOC in the alpine grasslands was derived from fresh plants, and the carbon in the CG was more stable than that in the AM and AS. The compositions of all the alpine ecosystems were stable under short-term climatic changes, suggesting the short-term climate warming and nitrogen deposition likely did not affect the molecular composition of the SOC in the restored grasslands. (C) 2017 Elsevier B.V. All rights reserved. C1 [Zhao, Zhenzhen; Dong, Shikui; Jiang, Xiaoman; Zhao, Jinbo; Liu, Shiliang; Yang, Mingyue; Han, Yuhui; Sha, Wei] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, 19 XinJieKouWai St, Beijing 100875, Peoples R China. EM dsk03037@bnu.edu.cn TC 16 Z9 16 PD JUN 1 PY 2018 VL 625 BP 539 EP 546 DI 10.1016/j.scitotenv.2017.12.206 UT WOS:000426356600054 DA 2023-03-23 ER PT J AU Badingquiying Smith, AT Harris, RB AF Badingquiying Smith, Andrew T. Harris, Richard B. TI Summer habitat use of plateau pikes (Ochotona curzoniae) in response to winter livestock grazing in the alpine steppe Qinghai-Tibetan Plateau SO ARCTIC ANTARCTIC AND ALPINE RESEARCH DT Article AB Plateau pikas (Ochotona curzoniae), burrowing lagomorphs endemic to the Qinghai-Tibetan Plateau (QTP), are considered pests by Chinese authorities because of their association with grasslands that are characterized as degraded. Officials typically blame pikas for causing the degraded conditions, whereas studies increasingly suggest that sparse vegetation encourages population growth and high densities of pikas. Correlational investigations that document pika density while simultaneously describing grassland conditions can quantify this association, but are uninformative regarding causation. We used livestock exclosures and pika reductions in partially controlled experiments to examine how pika habitat use responds to changes in vegetation structure caused by wintertime livestock grazing. Mean counts of pikas were higher on grazed than ungrazed plots. Linear models accounting for experimental pika reduction as well as seasonal phenology indicated that grazing significantly increased pika use compared with ungrazed plots. These results show that moderate livestock density is likely consistent with both biodiversity conservation and economic activity, and that high pika populations alone are not responsible for observed degradation of the QTP alpine grasslands. Moderate levels of livestock grazing and pika presence are consistent with maintaining the integrity of the alpine steppe ecosystem of the QTP. C1 [Badingquiying] Qinghai Normal Univ, Coll Geog Sci, Xining, Qinghai, Peoples R China. [Badingquiying] Qinghai Normal Univ, Qinghai Prov Key Lab Phys Geog & Environm Proc, Xining, Qinghai, Peoples R China. [Smith, Andrew T.] Arizona State Univ, Sch Life Sci, Tempe, AZ USA. [Harris, Richard B.] Univ Montana, Dept Ecosyst & Conservat Sci, Missoula, MT 59812 USA. [Harris, Richard B.] Washington Dept Fish & Wildlife, Olympia, WA USA. RP Harris, RB (通讯作者)，POB 43200, Olympia, WA 98504 USA. EM rharris@montana.com TC 6 Z9 6 PD MAY 30 PY 2018 VL 50 IS 1 AR e1447190 DI 10.1080/15230430.2018.1447190 UT WOS:000438737300001 DA 2023-03-23 ER PT J AU Okin, GS D'Odorico, P Liu, JQ AF Okin, Gregory S. D'Odorico, Paolo Liu, Jianquan TI A Mechanism of Land Degradation in Turf-Mantled Slopes of the Tibetan Plateau SO GEOPHYSICAL RESEARCH LETTERS DT Article AB Kobresia pygmaea meadows are typical of Tibetan Plateau landscapes in the 3,000 to 5,500 m elevation range and constitute the most extensive alpine ecosystem in the world. Kobresia pygmaea forms turf mats that stabilize the surface and shelter the underlying soils from water erosion. Large tracts of the Plateau, however, exhibit signs of ongoing degradation of the turf and erosion of the underlying soil. Despite the crucial role played by K. pygmaea turf mats in the stabilization of the headwaters of major Asian rivers, the mechanisms responsible for their degradation remain poorly investigated. Here we develop a process-based model of land degradation of Tibetan Plateau slopes, which accounts for (i) turf cracking, (ii) water flow concentration in the cracks, (iii) crack widening by scouring, and (iv) sheet-flow erosion. As expected, soil erosion increases with the slope and drainage area (hence the observation of stronger erosion in relatively steep downhill sites). Model simulations indicate that with a sensible set of parameters representative of soil and hydrologic conditions in the region, Tibetan Plateau landscapes are vulnerable to turf mat degradation and soil erosion. As soon as polygonal cracks develop, water flow widens them until the landscape is completely barren. At this point sheet flow eventually erodes the mineral soil leaving behind a highly degraded landscape. C1 [Okin, Gregory S.] Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90024 USA. [D'Odorico, Paolo] Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. [Liu, Jianquan] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou, Gansu, Peoples R China. RP Okin, GS (通讯作者)，Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90024 USA. EM okin@geog.ucla.edu TC 4 Z9 4 PD MAY 16 PY 2018 VL 45 IS 9 BP 4041 EP 4048 DI 10.1029/2018GL077055 UT WOS:000434111700033 DA 2023-03-23 ER PT J AU Ade, LJ Hu, L Zi, HB Wang, CT Lerdau, M Dong, SK AF Ade, L. J. Hu, L. Zi, H. B. Wang, C. T. Lerdau, M. Dong, S. K. TI Effect of snowpack on the soil bacteria of alpine meadows in the Qinghai-Tibetan Plateau of China SO CATENA DT Article AB Global climate change is accompanied by changes in the amounts of ice and snow. These changes have both a direct effect on the plant community structure, primary productivity and carbon cycle and an indirect influence on the belowground ecosystem. However, the effects of changes in snowpack on the soil environment and belowground ecological processes, particularly in soil microbial communities are still poorly understood in alpine meadows. We conducted a field study of controlled snowpack in the eastern margin of the Tibetan Plateau, where five treatments were set up, named as S0, S1, S2, S3, and S4 (S1: the amount of a natural snowpack; S2, S3, and S4 were twofold, threefold, and fourfold of Sl, respectively; and SO: completely removed snow). Soil physicochemical properties, soil community structure and diversity measured by 16S rRNA gene amplicons were studied. The results indicated that 1) as snowpack increased, the average soil temperature decreased, but soil moisture and soil compaction increased; 2) soil chemical properties (pH, available nitrogen, available potassium, available phosphorus, total nitrogen, total potassium, total phosphorus and total soil organic carbon) all changed as snowpack changed; and 3) increasing snowpack led to a decrease in the relative abundance of Acidobacteria, but Bacteroidetes and Actinobacteria did not decline in response to increasing snowpack. In summary, these results showed that soil bacterial communities are sensitive to changes in snowpack in alpine meadows. C1 [Ade, L. J.; Zi, H. B.] Southwest Univ Nationalities, Inst Qinghai Tibetan Plateau Res, Chengdu 610041, Sichuan, Peoples R China. [Hu, L.; Wang, C. T.] Southwest Univ Nationalities, Sch Life & Technol, Chengdu 610041, Sichuan, Peoples R China. [Lerdau, M.] Univ Virginia, Dept Environm Sci, Charlottesville, VA 22902 USA. [Dong, S. K.] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. RP Wang, CT (通讯作者)，Southwest Univ Nationalities, Sch Life & Technol, Chengdu 610041, Sichuan, Peoples R China. EM wangct@swun.edu.cn TC 24 Z9 26 PD MAY PY 2018 VL 164 BP 13 EP 22 DI 10.1016/j.catena.2018.01.004 UT WOS:000430031800002 DA 2023-03-23 ER PT J AU Che, RX Qin, JL Tahmasbian, I Wang, F Zhou, ST Xu, ZH Cui, XY AF Che, Rongxiao Qin, Jinling Tahmasbian, Iman Wang, Fang Zhou, Shutong Xu, Zhihong Cui, Xiaoyong TI Litter amendment rather than phosphorus can dramatically change inorganic nitrogen pools in a degraded grassland soil by affecting nitrogen-cycling microbes SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB Phosphorus fertilisation and increasing litter input are widely employed to restore the degraded grasslands. Despite the key roles of nitrogen-cycling microbes in determining the soil nitrogen dynamics and development of grassland degradation, little is known about their responses to these restoration efforts. Here, a microcosm experiment, with soils collected from a degraded Tibetan alpine meadow, was conducted to investigate the responses of nitrogen-cycling microbes to litter and phosphorus amendments, and their links with the changes in soil properties. Copies of the corresponding nitrogen-cycling genes (nifH, amoA, narG, nirK, and nirS genes) and their mRNAs were determined using real-time PCR. The results showed that the litter amendment significantly stimulated the transcription of nifH and nirS genes, but reduced the copies of amoA gene and bacterial amoA mRNA. It also significantly increased soil dissolved organic carbon, available phosphorus, ammonium nitrogen, and microbial biomass concentrations, but decreased soil inorganic and nitrate nitrogen concentrations. The phosphorus amendment exerted little effects on soil properties and nitrogen-cycling microbes, while the litter phosphorus interactions significantly offset the individual negative effects of the litter and phosphorus amendments on the denitrifier abundance. The soil nitrate and inorganic nitrogen concentrations were positively correlated with the amoA genes and bacterial amoA mRNA copies, but negatively correlated with nirS mRNA copies. These results indicate that litter addition may decrease soil nitrate and inorganic nitrogen concentrations by suppressing nitrifiers and stimulating nirS gene expression, highlighting the vital roles of nitrogen-cycling microbes in determining the soil nitrogen dynamics during the restoration of degraded grasslands. C1 [Che, Rongxiao; Qin, Jinling; Wang, Fang; Zhou, Shutong; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Che, Rongxiao; Tahmasbian, Iman; Wang, Fang; Xu, Zhihong] Griffith Univ, Environm Futures Res Inst, Sch Environm & Sci, Brisbane, Qld 4111, Australia. RP Cui, XY (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. EM cuixy@ucas.ac.cn TC 69 Z9 74 PD MAY PY 2018 VL 120 BP 145 EP 152 DI 10.1016/j.soilbio.2018.02.006 UT WOS:000430031900014 DA 2023-03-23 ER PT J AU Hedenec, P Singer, D Li, JB Yao, MJ Lin, Q Li, H Kukla, J Cajthaml, T Frouzc, J Rui, JP Li, XZ AF Hedenec, Petr Singer, David Li, Jiabao Yao, Minjie Lin, Qiang Li, Huan Kukla, Jaroslav Cajthaml, Tomas Frouzc, Jan Rui, Junpeng Li, Xiangzhen TI Effect of dry-rewetting stress on response pattern of soil prokaryotic communities in alpine meadow soil SO APPLIED SOIL ECOLOGY DT Article AB Soil microorganisms are recognized as key players in all biogeochemical cycles. However, little effort has been paid to incorporate them in predictive models for future climate change. Here, we investigated the variation of prokaryotic community composition in alpine meadow soil from the Qinghai-Tibet Plateau under dry-rewetting stress using MiSeq sequencing approach. We incubated soils treated by various frequencies of rewetting and durations of desiccation. Emission rates of methane, carbon dioxide and nitrous oxide were measured every week during five months of incubation, and soil samples were taken each month for community composition analysis. Our results revealed that soil prokaryotic community showed different response patterns to dry-wetting cycles. Diversity indices significantly increased in soils under short-term drought and soils rewetted after long-term drought. Higher niche partitioning was promoted by higher frequencies of disturbance and rapid physiological activation of inactive microbial communities during desiccation, allowing colonization by a diverse array of organisms. Null model percentage of NTI revealed a strong phylogenetic relatedness of soil prokaryotic communities across all treatments and incubation times, suggesting that desiccation and rewetting events were strong biological filters shaping community assemblies. Our results also indicated different responses of various genera belonging to same phylum. These results suggest that prokaryotes that are well adapted to extremely stressful conditions such as long-term desiccation may release more greenhouse gasses in a positive feedback loop and that this prospect should be considered when modeling climate change. C1 [Hedenec, Petr; Rui, Junpeng] Fujian Agr & Forestry Univ, Coll Resources & Environm, Fujian Prov Key Lab Soil Environm Hlth & Regulat, Fuzhou 350002, Fujian, Peoples R China. [Hedenec, Petr; Li, Jiabao; Yao, Minjie; Lin, Qiang; Li, Huan; Li, Xiangzhen] Chinese Acad Sci, Key Lab Environm & Appl Microbiol, Chengdu Inst Biol, Chengdu 610041, Sichuan, Peoples R China. [Hedenec, Petr; Li, Jiabao; Yao, Minjie; Lin, Qiang; Li, Huan; Li, Xiangzhen] Environm Microbiol Key Lab Sichuan Prov, Chengdu 610041, Sichuan, Peoples R China. [Hedenec, Petr; Kukla, Jaroslav; Cajthaml, Tomas; Frouzc, Jan] Charles Univ Prague, Fac Sci, Inst Environm Studies, Benatska 2, CR-12844 Prague 2, Czech Republic. [Hedenec, Petr; Kukla, Jaroslav; Cajthaml, Tomas; Frouzc, Jan] Charles Univ Prague, Fac Sci, SoWa Res Infrastruct, Benatska 2, CR-12844 Prague 2, Czech Republic. [Hedenec, Petr; Singer, David] Univ Neuchatel, Lab Soil Biodivers, Rue Emile Argand 11, Neuchatel, Switzerland. [Lin, Qiang; Frouzc, Jan] CAS, Biol Ctr, Inst Soil Biol, Sadkach 702-7, Ceske Budejovice 37005, Czech Republic. [Lin, Qiang; Frouzc, Jan] SoWa Res Infrastruct, Sadkach 702-7, Ceske Budejovice 37005, Czech Republic. [Cajthaml, Tomas] CAS, Inst Microbiol, Lab Environm Biotechnol, Videnska 1083, Prague 14220 4, Czech Republic. RP Rui, JP (通讯作者)，Fujian Agr & Forestry Univ, Coll Resources & Environm, Fujian Prov Key Lab Soil Environm Hlth & Regulat, Fuzhou 350002, Fujian, Peoples R China.; Li, XZ (通讯作者)，Chinese Acad Sci, Key Lab Environm & Appl Microbiol, Chengdu Inst Biol, Chengdu 610041, Sichuan, Peoples R China.; Li, XZ (通讯作者)，Environm Microbiol Key Lab Sichuan Prov, Chengdu 610041, Sichuan, Peoples R China. EM ruijp@cib.ac.cn; lixz@cib.ac.cn TC 8 Z9 8 PD MAY PY 2018 VL 126 BP 98 EP 106 DI 10.1016/j.apsoil.2018.02.015 UT WOS:000428332500011 DA 2023-03-23 ER PT J AU Wang, WH Wu, TH Zhao, L Li, R Zhu, XF Wang, WR Yang, SH Qin, YH Hao, JM AF Wang, Weihua Wu, Tonghua Zhao, Lin Li, Ren Zhu, Xiaofan Wang, Wanrui Yang, Shuhua Qin, Yanhui Hao, Junmin TI Exploring the ground ice recharge near permafrost table on the central Qinghai-Tibet Plateau using chemical and isotopic data SO JOURNAL OF HYDROLOGY DT Article AB Thawing permafrost on the Qinghai-Tibet Plateau (QTP) has great impacts on the local hydrological process by way of causing ground ice to thaw. Until now there is little knowledge on ground ice hydrology near permafrost table under a warming climate. This study applied stable tracers (isotopes and chloride) and hydrograph separation model to quantify the sources of ground ice near permafrost table in continuous permafrost regions of the central QTP. The results indicated that the ground ice near permafrost table was mainly supplied by active layer water and permafrost water, accounting for 58.9 to 87.0% and 13.0 to 41.1%, respectively, which implying that the active layer was the dominant source. The contribution rates from the active layer to the ground ice in alpine meadow (59 to 69%) was less than that in alpine steppe (70 to 87%). It showed well-developed hydrogeochemical depth gradients, presenting depleted isotopes and positive chemical gradients with depth within the soil layer. The effects of evaporation and freeze-out fractionation on the soil water and ground ice were evident. The results provide additional insights into ground ice sources and cycling near permafrost table in permafrost terrain, and would be helpful for improving process-based detailed hydrologic models under the occurring global warming. (C) 2018 Elsevier B.V. All rights reserved. C1 [Wang, Weihua; Wu, Tonghua; Zhao, Lin; Li, Ren; Zhu, Xiaofan; Yang, Shuhua; Qin, Yanhui; Hao, Junmin] Chinese Acad Sci, State Key Lab Cryosphere Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Gansu, Peoples R China. [Wang, Weihua; Wang, Wanrui] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Gansu, Peoples R China. [Wang, Weihua; Zhu, Xiaofan; Yang, Shuhua; Qin, Yanhui; Hao, Junmin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Wu, TH (通讯作者)，Chinese Acad Sci, State Key Lab Cryosphere Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Gansu, Peoples R China. EM thuawu@lzb.ac.cn TC 28 Z9 32 PD MAY PY 2018 VL 560 BP 220 EP 229 DI 10.1016/j.jhydrol.2018.03.032 UT WOS:000430882300017 DA 2023-03-23 ER PT J AU Yang, Y Hopping, KA Wang, GX Chen, J Peng, AH Klein, JA AF Yang, Yan Hopping, Kelly A. Wang, Genxu Chen, Ji Peng, Ahui Klein, Julia A. TI Permafrost and drought regulate vulnerability of Tibetan Plateau grasslands to warming SO ECOSPHERE DT Article AB The Tibetan Plateau has the largest expanse of high-elevation permafrost in the world, and it is experiencing climate warming that may jeopardize the functioning of its alpine ecosystems. Many studies have focused on the effects of climate warming on vegetation production and diversity on the Plateau, but their disparate results have hindered a comprehensive, regional understanding. From a synthesis of twelve warming experiments across the Plateau, we found that warming increased aboveground net primary production (ANPP) and vegetation height at sites with permafrost, but ANPP decreased with warming at non-permafrost sites. Aboveground net primary production responded more negatively to warming under drier conditions, due to both annual drought conditions and warming-induced soil moisture loss. Decreases in species diversity with warming were also larger at sites with permafrost. These results support the emerging understanding that water plays a central role in the functioning of cold environments and suggest that as ecosystems cross a threshold from permafrost to non-permafrost systems, ANPP will decrease across a greater proportion of the Tibetan Plateau. This study also highlights the future convergence of challenges from permafrost degradation and grassland desertification, requiring new collaborations among these currently distinct research and stakeholder groups. C1 [Yang, Yan; Wang, Genxu; Peng, Ahui] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Sichuan, Peoples R China. [Yang, Yan; Klein, Julia A.] Colorado State Univ, Dept Ecosyst Sci & Sustainabil, Campus Delivery 1476, Ft Collins, CO 80523 USA. [Hopping, Kelly A.] Stanford Univ, Dept Earth Syst Sci, 473 Via Ortega, Stanford, CA 94305 USA. [Chen, Ji] Chinese Acad Sci, State Key Lab Loess & Quaternary Geol, Inst Earth Environm, Xian 710061, Shaanxi, Peoples R China. [Chen, Ji] Chinese Acad Sci, Key Lab Aerosol Chem & Phys, Inst Earth Environm, Xian 710061, Shaanxi, Peoples R China. [Chen, Ji] Northwestern Polytech Univ, Ctr Ecol & Environm Sci, Xian 710072, Shaanxi, Peoples R China. RP Klein, JA (通讯作者)，Colorado State Univ, Dept Ecosyst Sci & Sustainabil, Campus Delivery 1476, Ft Collins, CO 80523 USA. EM julia.klein@colostate.edu TC 44 Z9 47 PD MAY PY 2018 VL 9 IS 5 AR e02233 DI 10.1002/ecs2.2233 UT WOS:000435640100026 DA 2023-03-23 ER PT J AU Che, RX Deng, YC Wang, WJ Rui, YC Zhang, J Tahmasbian, I Tang, L Wang, SP Wang, YF Xu, ZH Cui, XY AF Che, Rongxiao Deng, Yongcui Wang, Weijin Rui, Yichao Zhang, Jing Tahmasbian, Iman Tang, Li Wang, Shiping Wang, Yanfen Xu, Zhihong Cui, Xiaoyong TI Long-term warming rather than grazing significantly changed total and active soil procaryotic community structures SO GEODERMA DT Article AB There is a paucity of knowledge in understanding the effects of warming and grazing on soil microbes and their active counterparts, especially on the Tibetan Plateau which is extremely sensitive to global warming and human activities. A six-year field experiment was conducted to investigate the effects of asymmetric warming and moderate grazing on total and active soil microbes in a Tibetan Kobresia alpine meadow. Soil bacterial abundance and 16S rDNA transcriptional activity were determined using real-time PCR. Total and active soil procaryotic community structures were analyzed through MiSeq sequencing based on 16S rDNA and rRNA, respectively. The results showed that the soil procaryotic community was more sensitive to the warming than the grazing. The warming significantly decreased soil microbial respiration rates, 16S rDNA transcription activity, and dispersion of total procaryotic community structures, but significantly increased the alpha diversity of active procaryotes. Warming also significantly increased the relative abundance of oligotrophic microbes, whereas decreasing the copiotrophic lineage proportions. The functional profiles predicted from the total procaryotic community structures remained unaffected by warming. However, the rRNA-based predictions suggested that DNA replication, gene expression, signal transduction, and protein degradation were significantly suppressed under the warming. The grazing only significantly decreased the 16S rDNA transcription and total procaryotic richness. Overall, these findings suggest that warming can shift soil procaryotic community to a more oligotrophic and less active status, highlighting the importance of investigating active microbes to improve our understanding of ecosystem feedbacks to climate change and human activities. C1 [Che, Rongxiao; Zhang, Jing; Tang, Li; Wang, Yanfen; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Che, Rongxiao; Wang, Weijin; Tahmasbian, Iman; Tang, Li; Xu, Zhihong] Griffith Univ, Sch Nat Sci, Environm Futures Res Inst, Brisbane, Qld 4111, Australia. [Deng, Yongcui] Nanjing Normal Univ, Nanjing 210097, Jiangsu, Peoples R China. [Deng, Yongcui] Jiangsu Ctr Collaborat Innovat Geog Informat Reso, Nanjing 210023, Jiangsu, Peoples R China. [Wang, Weijin] Dept Sci Informat Technol & Innovat DSITI, Brisbane, Qld 4068, Australia. [Rui, Yichao] Univ Wisconsin Madison, Dept Soil Sci, Madison, WI 53706 USA. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. RP Cui, XY (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. EM cuixy@ucas.ac.cn TC 37 Z9 38 PD APR 15 PY 2018 VL 316 BP 1 EP 10 DI 10.1016/j.geoderma.2017.12.005 UT WOS:000424179300001 DA 2023-03-23 ER PT J AU Wang, YX Hodgkinson, KC Hou, FJ Wang, ZF Chang, SH AF Wang, Yingxin Hodgkinson, Kenneth C. Hou, Fujiang Wang, Zhaofeng Chang, Shenghua TI An evaluation of government-recommended stocking systems for sustaining pastoral businesses and ecosystems of the Alpine Meadows of the Qinghai-Tibetan Plateau SO ECOLOGY AND EVOLUTION DT Article AB China introduced the Retire Livestock and Restore Grassland policy in 2003. It was strengthened in 2011 by additional funding for on-farm structures. On the Qinghai-Tibetan Plateau (QTP), fences were erected, livestock excluded from degraded areas, rotational stocking introduced, nighttime shelters were built, forages grown, and seed sown. However, the effectiveness of these actions and their value to Tibetan herders has been questioned. We conducted a sheep stocking experiment for 5years in an Alpine Meadow region of the QTP to evaluate stocking options recommended by Government. Cold and warm season stocking each at three rates (0, 8, and 16sheep/ha) and continuous stocking at 0 and 4sheep/ha were compared. We measured live weights of sheep, plant species richness and evenness, root biomass and carbon (C), nitrogen (N) and phosphorus (P) contents of the 0-10cm of soil. We found that resting grassland from stocking during the warm season for later cold season stocking significantly reduced plant species richness and evenness and root biomass but not soil C, N, and P. During cold season stocking, live weights of sheep declined whether at a stocking rate of 8 or 16 per ha. In contrast, sheep continuously stocked on grassland at 4 per ha gained weight throughout both the warm and cold seasons and plant species richness and evenness were maintained. Warm season stocking at 8 and 16sheep/ha increased plant species richness and root biomass but reduced plant species evenness. Resting these alpine grasslands from stocking in the warm season has adverse consequences for plant conservation. Fencing from stocking in the warm season is not justified by this study; all grassland should be judiciously stocked during the warm season to maintain plant species richness. Neither resting nor stocking during the cold season appears to have any adverse consequences but sheltering and in-door feeding of sheep during the cold season may be more profitable than cold season stocking with use of open nighttime yards. C1 [Wang, Yingxin; Hou, Fujiang; Wang, Zhaofeng; Chang, Shenghua] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Key Lab Grassland Livestock Ind Innovat,Minist Ag, Lanzhou, Gansu, Peoples R China. [Hodgkinson, Kenneth C.] CSIRO Land & Water, Canberra, ACT, Australia. RP Hodgkinson, KC (通讯作者)，CSIRO Land & Water, Canberra, ACT, Australia.; Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou, Gansu, Peoples R China. EM ken.hodgkinson@csiro.au; cyhoufj@lzu.edu.cn TC 17 Z9 17 PD APR PY 2018 VL 8 IS 8 BP 4252 EP 4264 DI 10.1002/ece3.3960 UT WOS:000430807200038 DA 2023-03-23 ER PT J AU Liu, T Wang, L Feng, XJ Zhang, JB Ma, T Wang, X Liu, ZG AF Liu, Ting Wang, Liang Feng, Xiaojuan Zhang, Jinbo Ma, Tian Wang, Xin Liu, Zongguang TI Comparing soil carbon loss through respiration and leaching under extreme precipitation events in arid and semiarid grasslands SO BIOGEOSCIENCES DT Article AB Respiration and leaching are two main processes responsible for soil carbon loss. While the former has received considerable research attention, studies examining leaching processes are limited, especially in semiarid grass-lands due to low precipitation. Climate change may increase the extreme precipitation event (EPE) frequency in arid and semiarid regions, potentially enhancing soil carbon loss through leaching and respiration. Here we incubated soil columns of three typical grassland soils from Inner Mongolia and the Qinghai-Tibetan Plateau and examined the effect of simulated EPEs on soil carbon loss through respiration and leaching. EPEs induced a transient increase in CO2 release through soil respiration, equivalent to 32 and 72% of the net ecosystem productivity (NEP) in the temperate grass-lands (Xilinhot and Keqi) and 7% of NEP in the alpine grass-lands (Gangcha). By comparison, leaching loss of soil carbon accounted for 290, 120, and 15% of NEP at the corresponding sites, respectively, with dissolved inorganic carbon (DIC, biogenic DIC C lithogenic DIC) as the main form of carbon loss in the alkaline soils. Moreover, DIC loss increased with recurring EPEs in the soil with the highest pH due to an elevated contribution of dissolved CO2 from organic carbon degradation (indicated by DIC-delta C-13). These results highlight the fact that leaching loss of soil carbon (particularly in the form of DIC) is important in the regional carbon budget of arid and semiarid grasslands and also imply that SOC mineralization in alkaline soils might be underestimated if only measured as CO2 emission from soils into the atmosphere. With a projected increase in EPEs under climate change, soil carbon leaching processes and the influencing factors warrant a better understanding and should be incorporated into soil carbon models when estimating carbon balance in grassland ecosystems. C1 [Liu, Ting; Wang, Liang; Feng, Xiaojuan; Ma, Tian; Wang, Xin; Liu, Zongguang] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Feng, Xiaojuan; Ma, Tian; Wang, Xin] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhang, Jinbo] Nanjing Normal Univ, Sch Geog Sci, Nanjing 210023, Jiangsu, Peoples R China. RP Feng, XJ (通讯作者)，Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China.; Feng, XJ (通讯作者)，Univ Chinese Acad Sci, Beijing, Peoples R China. EM xfeng@ibcas.ac.cn TC 20 Z9 22 PD MAR 16 PY 2018 VL 15 IS 5 BP 1627 EP 1641 DI 10.5194/bg-15-1627-2018 UT WOS:000427717900002 DA 2023-03-23 ER PT J AU Zhang, YJ Pan, Y Zhang, XZ Wu, JX Yu, CQ Li, M Wu, JS AF Zhang, Yanjie Pan, Ying Zhang, Xianzhou Wu, Junxi Yu, Chengqun Li, Meng Wu, Jianshuang TI Patterns and dynamics of the human appropriation of net primary production and its components in Tibet SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Anthropogenic activities have induced profound changes across the globe. Human appropriation of net primary production (HANPP) is a useful indicator for quantifying anthropogenic influences on natural ecosystems. We applied a detailed HANPP framework to the Tibet Autonomous Region of China for the period 1989-2015 and performed clustering analysis to explore county-level dynamics of HANPP components. The results indicated a continuous increase in HANPP per unit area from 103 g C/m(2)/yr in 1989 to 18.5 g C/m(2)/yr in 2008, with some fluctuation and a decline to 16.8 C/m(2)/yr in 2015. As a percentage of potential net primary production (NPPpot), HANPP increased from 6.9% to 13.5%. This rise was mainly driven by the commercialization of animal husbandry and by ecological conservation policies. Animal stocks dominated HANPP in Tibet in 1989, and by 2015 beef or crop production had become predominant in 30 of 73 counties. However, HANPP did not change uniformly across all locations. Changes were mainly concentrated in the south-central river valley area because of the growth in beef and crop production there. While in almost half of the 73 counties located in the northwestern regions, HANPP was dominated by sheep stocks and changed only slightly over the study period. These findings indicate that a comprehensive spatiotemporal analysis of HANPP components in Tibet provides deeper insights into changes in production and livelihood strategies of local residents, aligned with ecological conservation policies and economic development. Moreover, it unravels the complex impacts of human activities on alpine ecosystems, and indicates the need to optimize local ecosystem management and conservation policies. (C) 2018 Elsevier Ltd. All rights reserved. C1 [Zhang, Yanjie; Zhang, Xianzhou; Wu, Junxi; Yu, Chengqun; Li, Meng; Wu, Jianshuang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Zhang, Yanjie; Zhang, Xianzhou; Li, Meng] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Pan, Ying] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Wu, Jianshuang] Free Univ Berlin, Inst Biol, Biodivers Ecol Modelling, D-14195 Berlin, Germany. RP Zhang, XZ; Wu, JX (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. EM zhangxz@igsnrr.ac.cn; wujx@igsnrr.ac.cn TC 18 Z9 24 PD MAR 15 PY 2018 VL 210 BP 280 EP 289 DI 10.1016/j.jenvman.2018.01.039 UT WOS:000425559900026 DA 2023-03-23 ER PT J AU Liu, WJ Chen, SY Liang, JY Qin, X Kang, SC Ren, JW Qin, DH AF Liu, Wenjie Chen, Shengyun Liang, Junyi Qin, Xiang Kang, Shichang Ren, Jiawen Qin, Dahe TI The effect of decreasing permafrost stability on ecosystem carbon in the northeastern margin of the Qinghai-Tibet Plateau SO SCIENTIFIC REPORTS DT Article AB The objective of this study is to investigate the effect of decreased permafrost stability on carbon storage of the alpine ecosystems in the northeastern margin of the Qinghai-Tibet Plateau. During July and August 2013, we selected 18 sites in five types of permafrost (stable, substable, transitional, unstable, and extremely unstable) regions. We measured aboveground phytomass carbon (APC) and soil respiration (SR), soil inorganic carbon (SIC), soil organic carbon (SOC), belowground phytomass carbon, and soil properties down to 50 cm at same types of soils and grasslands. The results indicated that ecosystem carbon in cold calcic soils first decreased and then increased as the permafrost stability declined. Overall, decreasing permafrost stability was expected to reduce ecosystem carbon in meadows, but it was not obvious in swamp meadows and steppes. APC decreased significantly, but SIC and SOC in steppes first decreased and then increased with declining permafrost stability. Soil clay fraction and soil moisture were the controls for site variations of ecosystem carbon. The spatial variations in SR were possibly controlled by soil moisture and precipitation. This meant that alpine ecosystems carbon reduction was strongly affected by permafrost degradation in meadows, but the effects were complex in swamp meadows and steppes. C1 [Liu, Wenjie] Hainan Univ, Inst Trop Agr & Forestry, Haikou 570228, Hainan, Peoples R China. [Liu, Wenjie; Chen, Shengyun; Qin, Xiang; Kang, Shichang; Ren, Jiawen; Qin, Dahe] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Qilian Shan Stn Glaciol & Ecol Environm, State Key Lab Cryospher Sci, Lanzhou 730000, Gansu, Peoples R China. [Liang, Junyi] Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. [Liang, Junyi] Oak Ridge Natl Lab, Climate Change Sci Inst, Oak Ridge, TN 37831 USA. RP Chen, SY (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Qilian Shan Stn Glaciol & Ecol Environm, State Key Lab Cryospher Sci, Lanzhou 730000, Gansu, Peoples R China. EM sychen@lzb.ac.cn TC 3 Z9 3 PD MAR 8 PY 2018 VL 8 AR 4172 DI 10.1038/s41598-018-22468-6 UT WOS:000426825900007 DA 2023-03-23 ER PT J AU Fu, YF Liu, CY Lin, F Hu, XX Zheng, XH Zhang, W Ca, GM AF Fu, Yongfeng Liu, Chunyan Lin, Fei Hu, Xiaoxia Zheng, Xunhua Zhang, Wei Ca, Guangmin TI Quantification of year-round methane and nitrous oxide fluxes in a typical alpine shrub meadow on the Qinghai-Tibetan Plateau SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Alpine meadows are the largest grasslands in China. Greenhouse gas exchanges between alpine meadows and the atmosphere are highly uncertain due to the lack of year-round flux measurements. In this study, the methane (CH4) and nitrous oxide (N2O) fluxes in an alpine Potentilla fruticosa shrub meadow in the Qinghai-Tibetan Plateau were investigated using the static, opaque chamber-gas chromatography method between April 2012 and April 2015. The annual CH4 uptake (1.33-1.35 kg C ha(-1) yr(-1)) and Q(10), value (1.79) were at the low end of the range for natural grasslands in China, which indicated that global warming at the same extent would result in less of an increase in the CH4 sink in the Qinghai-Tibetan Plateau, compared to other grassland areas. The N2O emissions during the spring thaw period showed a tremendous inter-annual variation (0.03 to 0.14 kg N ha(-1)), which was closely linked to the variation in annual precipitation, especially the precipitation of the previous growing season. The high substrate concentrations and soil moisture during the spring thaw periods together provided the conditions for pulse N2O emissions. When the pulse N2O emissions occurred, emissions from the non-growing seasons dominated (67-74%) the annual total emissions. Thus, a proper sampling frequency (daily to weekly measurements) in non-growing seasons was needed for the quantification of annual fluxes. Four gas chromatographic set-ups (the Ar-CH4, N-2-ascarite, N-2-CO2, and pure N-2 methods) were adopted for N2O flux measurements over natural grasslands in China. Using the N-2-CO2 method, the annual N2O emissions from the alpine shrub meadow were quantified to be only 0.18-0.27 kg N ha(-1) yr(-1) in the present study. Based on measurements using the first three of the four gas chromatographic set-ups, the conclusion that can be drawn is that unfertilized natural grasslands in China function as marginally weak N2O sources, whereas the pure N-2 method may remarkably overestimate the emissions. C1 [Fu, Yongfeng; Liu, Chunyan; Lin, Fei; Hu, Xiaoxia; Zheng, Xunhua; Zhang, Wei] Chinese Acad Sci, Inst Atmospher Phys, State Key Lab Atmospher Boundary Layer Phys & Atm, Beijing 100029, Peoples R China. [Fu, Yongfeng; Lin, Fei; Hu, Xiaoxia; Zheng, Xunhua] Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China. [Ca, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Qinghai, Peoples R China. RP Liu, CY (通讯作者)，Chinese Acad Sci, Inst Atmospher Phys, State Key Lab Atmospher Boundary Layer Phys & Atm, Beijing 100029, Peoples R China. EM lcy@post.iap.ac.cn TC 27 Z9 32 PD MAR 1 PY 2018 VL 255 BP 27 EP 36 DI 10.1016/j.agee.2017.12.003 UT WOS:000425578600004 DA 2023-03-23 ER PT J AU Gao, ZY Niu, FJ Wang, YB Lin, ZJ Luo, J Liu, MH AF Gao, Zeyong Niu, Fujun Wang, Yibo Lin, Zhanju Luo, Jing Liu, Minghao TI Root-induced changes to soil water retention in permafrost regions of the Qinghai-Tibet Plateau, China SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Soil water retention plays a crucial role in regulating soil moisture dynamics, water circulation, plant growth, contaminant transport, and permafrost stability, and it is an issue of concern in water-limited ecosystems. However, our understanding of the relationship between plant roots and soil water retention is still relatively poor in the alpine grasslands of permafrost regions. To addresses this, our study evaluated the effect of plants on the soil water retention in permafrost regions of the Qinghai-Tibet Plateau. Three alpine grassland sites were identified and characterized as alpine wet meadow (AWM), alpine meadow (AM), and alpine steppe (AS). Root biomass, soil water retention, and soil physico-chemical properties were examined in the top 0-50 cm of active layer in the three experimental sites in the hinterland of the Qinghai-Tibet Plateau (QTP). Pedotransfer functions (PTFs) and Retention Curve program (RETC) were employed to illustrate how the plant roots affect soil water retention. Approximately 80, 65, and 60% of root biomass was distributed in the top 0-20 cm in the AWM, AM, and AS soil, respectively. Soil water retention was enhanced with the presence of plant roots; thereinto, the highest values of field capacity were found in AWM soil: on average, about 0.45 cm(3) cm(-3). Field capacity of AWM soil was almost twice as high as that of AM soil, and triple higher than that of AS soil. Correlation and regression analysis showed that root-induced changes to soil water retention were caused by altering the soil organic matter and soil structure. In addition, we evaluated the Retention Curve (RETC) program's performance and found that the program underestimated soil water retention if the effects of plant roots were not considered. A lack of alpine plants is associated with a decline in soil physical conditions and soil water retention in permafrost regions, and the function of plant roots should be considered when predicting hydrological processes. C1 [Gao, Zeyong; Niu, Fujun] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. [Gao, Zeyong] Univ Chinese Acad Sci, 19 Yuquan Rd, Beijing 100049, Peoples R China. [Gao, Zeyong; Wang, Yibo; Lin, Zhanju; Luo, Jing; Liu, Minghao] Lanzhou Univ, Coll Earth & Environm Sci, 222 Tianshui South Rd, Lanzhou 730000, Gansu, Peoples R China. RP Niu, FJ (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resources, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China. EM niufujun@lzb.ac.cn TC 24 Z9 29 PD MAR PY 2018 VL 18 IS 3 BP 791 EP 803 DI 10.1007/s11368-017-1815-0 UT WOS:000426070100013 DA 2023-03-23 ER PT J AU Li, Q AF Li, Quan TI Spatial variability and long-term change in pollen diversity in Nam Co catchment (central Tibetan Plateau): Implications for alpine vegetation restoration from a paleoecological perspective SO SCIENCE CHINA-EARTH SCIENCES DT Article AB Pollen diversity offers abundant clues into the floristic diversity and history of vegetation change. Few palynological studies investigated modern pollen diversity or the past floristic diversity on the Tibetan Plateau (TP). Based on modern pollen assemblages from 37 topsoils and 63 surface lake sediments in the Nam Co catchment on the central TP, this study quantitatively explored spatial distribution of modern pollen diversity using Shannon-Wiener index (H) and palynological richness (E(T (n) ), n=600). Pollen diversity indices showed spatial variability among vegetation types, reflecting the differences in terrestrial floristic diversity in the lake catchment. Their values were high in the southeastern region of the lake catchment which is covered by alpine steppe, while values were low for alpine meadow and marsh meadow. The pollen diversity in lacustrine pollen assemblage could be an effective proxy to document past floristic diversity. The past floristic diversity in the lake catchment, recovered from a fossil pollen record of NMLC-1, showed a long-term change of ascending overlaid by several rapid diversity changes during the last 8400 years due to the downward shift of altitudinal vegetation belt driven by a general climatic cooling. The results imply that under the environmental challenge of climate warming and vegetation degradation, alpine vegetation restoration in the Nam Co catchment and the central TP should pay attention to altitudinal vegetation belt and zonal vegetation of alpine steppe, and use the long-term change of floristic diversity as a historical analogue. C1 [Li, Quan] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. RP Li, Q (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM liquan@igsnrr.ac.cn TC 12 Z9 13 PD MAR PY 2018 VL 61 IS 3 BP 270 EP 284 DI 10.1007/s11430-017-9133-0 UT WOS:000426574800003 DA 2023-03-23 ER PT J AU Shao, KQ Gao, G AF Shao, Keqiang Gao, Guang TI Soil microbial communities of three grassland ecosystems in the Bayinbuluke, China SO CANADIAN JOURNAL OF MICROBIOLOGY DT Article AB The microbial community plays an important role in soil nutrient cycles and energy transformations in alpine grassland. In this study, we investigated the composition of the soil microbial community collected from alpine cold swamp meadow (ASM), alpine cold meadow (AM), and alpine cold desert steppe (ADS) within the Bayinbuluke alpine grassland, China, using Illumina amplicon sequencing. Of the 147 271 sequences obtained, 36 microbial phyla or groups were detected. The results showed that the ADS had lower microbial diversity than the ASM and AM, as estimated by the Shannon index. The Verrucomicrobia, Chloroflexi, Planctomycetes, Proteobacteria, and Actinobacteria were the predominant phyla in all 3 ecosystems. Particularly, Thaumarchaeota was only abundant in ASM, Bacteroidetes in AM, and Acidobacteria in ADS. Additionally, the predominant genus also differed with each ecosystem. Candidatus Nitrososphaera was predominant in ADS, the Pir4 lineage in ASM, and Sphingomonas in AM. Our results indicated that the soil microbial community structure was different for each grassland ecosystem in the Bayinbuluke. C1 [Shao, Keqiang; Gao, Guang] Chinese Acad Sci, Nanjing Inst Geog & Limnol, State Key Lab Lake Sci & Environm, Nanjing 210008, Jiangsu, Peoples R China. RP Gao, G (通讯作者)，Chinese Acad Sci, Nanjing Inst Geog & Limnol, State Key Lab Lake Sci & Environm, Nanjing 210008, Jiangsu, Peoples R China. EM guanggao@niglas.ac.cn TC 5 Z9 5 PD MAR PY 2018 VL 64 IS 3 BP 209 EP 213 DI 10.1139/cjm-2017-0585 UT WOS:000425813000005 DA 2023-03-23 ER PT J AU Wang, YH Xu, YP Spencer, RGM Zito, P Kellerman, A Podgorski, D Xiao, WJ Wei, DD Rashid, H Yang, YH AF Wang, Yinghui Xu, Yunping Spencer, Robert G. M. Zito, Phoebe Kellerman, Anne Podgorski, David Xiao, Wenjie Wei, Dandan Rashid, Harunur Yang, Yuanhe TI Selective Leaching of Dissolved Organic Matter From Alpine Permafrost Soils on the Qinghai-Tibetan Plateau SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES DT Article AB Ongoing global temperature rise has caused significant thaw and degradation of permafrost soils on the Qinghai-Tibetan Plateau (QTP). Leaching of organic matter from permafrost soils to aquatic systems is highly complex and difficult to reproduce in a laboratory setting. We collected samples from natural seeps of active and permafrost layers in an alpine swamp meadow on the QTP to shed light on the composition of mobilized dissolved organic matter (DOM) by combining optical measurements, ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry, radiocarbon (C-14), and solid-state C-13 nuclear magnetic resonance spectroscopy. Our results show that even though the active layer soils contain large amounts of proteins and carbohydrates, there is a selective release of aromatic components, whereas in the deep permafrost layer, carbohydrate and protein components are preferentially leached during the thawing process. Given these different chemical characteristics of mobilized DOM, we hypothesize that photomineralization contributes significantly to the loss of DOM that is leached from the seasonally thawed surface layer. However, with continued warming, biodegradation will become more important since biolabile materials such as protein and carbohydrate are preferentially released from deep-layer permafrost soils. This transition in DOM leachate source and associated chemical composition has ramifications for downstream fluvial networks on the QTP particularly in terms of processing of carbon and associated fluxes. C1 [Wang, Yinghui; Xu, Yunping; Xiao, Wenjie; Wei, Dandan; Rashid, Harunur] Shanghai Ocean Univ, Coll Marine Sci, Shanghai Engn Res Ctr Hadal Sci & Technol, Shanghai, Peoples R China. [Wang, Yinghui; Xiao, Wenjie] Peking Univ, Coll Urban & Environm Sci, Key Lab Earth Surface Proc, Minist Educ, Beijing, Peoples R China. [Spencer, Robert G. M.; Kellerman, Anne] Florida State Univ, Natl High Magnet Field Lab, Geochem Grp, Tallahassee, FL 32306 USA. [Spencer, Robert G. M.; Kellerman, Anne] Florida State Univ, Dept Earth Ocean & Atmospher Sci, Tallahassee, FL 32306 USA. [Zito, Phoebe; Podgorski, David] Univ New Orleans, Dept Chem, Pontchartrain Inst Environm Sci, New Orleans, LA 70148 USA. [Yang, Yuanhe] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. RP Xu, YP (通讯作者)，Shanghai Ocean Univ, Coll Marine Sci, Shanghai Engn Res Ctr Hadal Sci & Technol, Shanghai, Peoples R China. EM ypxu@shou.edu.cn TC 15 Z9 15 PD MAR PY 2018 VL 123 IS 3 BP 1005 EP 1016 DI 10.1002/2017JG004343 UT WOS:000430181200018 DA 2023-03-23 ER PT J AU Zhang, NN Sun, G Liang, J Wang, ET Shi, CG He, J Hu, X Zhao, CZ Wu, N AF Zhang, Nan Nan Sun, Geng Liang, Jin Wang, En Tao Shi, Chang Guang He, Jing Hu, Xia Zhao, Chun Zhang Wu, Ning TI Response of ammonium oxidizers to the application of nitrogen fertilizer in an alpine meadow on the Qinghai-Tibetan Plateau SO APPLIED SOIL ECOLOGY DT Article AB The alpine meadows in Qinghai-Tibetan Plateau is an ecosystem sensitive to environmental changes. As part of a study on global climate change and the effects of N precipitation on soil microbiota, we fingerprinted ammonium oxidizing archaea (AOA) and bacteria (AOB) in relation to the N supplement in an alpine meadow in Qinghai Tibetan Plateau. The results showed that nutrient content in the studied soil was significantly varied in different months (sampling period) but not influenced by the N supplement rate. Long-term nitrogen input dramatically changed the abundance and community composition of the AOB but exerted no obvious effect on the AOA community in the tested soil. Significant differences in the abundance and composition of AOA were recorded in different months. Our findings implied that 1) the soil fertility and physicochemical features of the studied alpine meadows in Qinghai-Tibetan Plateau were stable even under the long-term high N supply; 2) AOB might be the active nitrifiers responding to the high N supply, while the AOA were the abundant and stable nitrifiers despite the N supply; 3) sampling periods mainly affected the abundance and community composition of the nitrifiers in the tested alpine meadow; and 4) the AOB in the studied area are psychrotrophs. Therefore, despite the enhancement of plant growth, high N supplements in the tested alpine meadow ecosystems might cause more pollution to water and air, which in turn contributes to global climate change. C1 [Zhang, Nan Nan; Sun, Geng; Liang, Jin; Shi, Chang Guang; He, Jing; Zhao, Chun Zhang; Wu, Ning] Chinese Acad Sci, Chengdu Inst Biol, POB 416, Chengdu 610041, Sichuan, Peoples R China. [Zhang, Nan Nan; Sun, Geng; Liang, Jin; Shi, Chang Guang; He, Jing; Zhao, Chun Zhang; Wu, Ning] Chinese Acad Sci, Chengdu Inst Biol, CAS Key Lab Mt Ecol Restorat & Bioresource Utiliz, Chengdu, Sichuan, Peoples R China. [Zhang, Nan Nan; Sun, Geng; Liang, Jin; Shi, Chang Guang; He, Jing; Zhao, Chun Zhang; Wu, Ning] Chinese Acad Sci, Chengdu Inst Biol, Biodivers Conservat Key Lab Sichuan Prov, Chengdu, Sichuan, Peoples R China. [Wang, En Tao] Inst Politecn Nacl, Escuela Nacl Ciencias Biol, Mexico City 11340, DF, Mexico. [Hu, Xia] Leshan Normal Univ, Leshan 614000, Peoples R China. RP Sun, G (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, POB 416, Chengdu 610041, Sichuan, Peoples R China. EM sungeng@cib.ac.cn TC 12 Z9 14 PD MAR PY 2018 VL 124 BP 266 EP 274 DI 10.1016/j.apsoil.2017.11.018 UT WOS:000428331000033 DA 2023-03-23 ER PT J AU Zhu, XC Shao, MA Liang, Y AF Zhu, Xuchao Shao, Ming'an Liang, Yin TI Spatiotemporal characteristics and temporal stability of soil water in an alpine meadow on the northern Tibetan Plateau SO CANADIAN JOURNAL OF SOIL SCIENCE DT Article AB The spatiotemporal characteristics of soil water content (SWC) have a significant influence on vegetation degradation and growth in alpine meadow ecosystems. The spatiotemporal variability and temporal stability (TS) of SWC, however, have rarely been studied on the northern Tibetan Plateau owing to the rugged and hostile sampling environment. The objective of this study was to analyze the spatiotemporal variability and the TS of SWC in various layers of the soil, to a depth of 50 cm in a 33.5 hm(2) plot, with the data obtained from 113 measuring locations collected on 22 sampling occasions during the growing seasons of 2015 and 2016. The SWC was moderately variable both in time (two consecutive growing seasons) and horizontal space (plot). The variabilities, however, did not vary consistently with increasing depth for the various dominant influencing factors. The SWC in the undeveloped, shallow, and stony alpine meadow soil was temporally stable; TS did not depend on depth due to disturbances by grass roots and stones. The best representative location of TS at each depth could be determined, and all accurately estimated the field mean SWC. Vegetation coverage, soil organic carbon, gravel and stone contents, and saturated hydraulic conductivity were the main factors influencing TS. This study provides useful information for the management of alpine meadows and provides an effective method for studying SWC at a hectometre scale on the Tibetan Plateau. C1 [Zhu, Xuchao; Liang, Yin] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Jiangsu, Peoples R China. [Shao, Ming'an] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Shao, Ming'an] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. RP Shao, MA (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China.; Shao, MA (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. EM shaoma@igsnrr.ac.cn TC 10 Z9 11 PD MAR PY 2018 VL 98 IS 1 BP 161 EP 174 DI 10.1139/cjss-2017-0078 UT WOS:000426967900014 DA 2023-03-23 ER PT J AU Ma, BB Sun, J AF Ma, Baibing Sun, Jian TI Predicting the distribution of Stipa purpurea across the Tibetan Plateau via the MaxEnt model SO BMC ECOLOGY DT Article AB Background: The ecosystems across Tibetan Plateau are changing rapidly under the influence of climate warming, which has caused substantial changes in spatial and temporal environmental patterns. Stipa purpurea, as a dominant herbsage resource in alpine steppe, has a great influence on animal husbandry in the Tibetan Plateau. Global warming has been forecasted to continue in the future (2050s, 2070s), questioning the future distribution of S. purpurea and its response to climate change. The maximum entropy (MaxEnt) modeling, due to its multiple advantages (e.g. uses presence-only data, performs well with incomplete data, and requires small sample sizes and gaps), has been used to understand species environment relationships and predict species distributions across locations that have not been sampled. Results: Annual mean temperature, annual precipitation, temperature seasonality, altitude, and precipitation during the driest month, significantly affected the distribution of S. purpurea. Only 0.70% of the Tibetan Plateau area included a very highly suitable habitat (habitat suitability [HS] = 0.8-1.0). Highly suitable habitat (HS = 0.6-0.8), moderately suitable habitat (HS = 0.4-0.6), and unsuitable habitat (HS = 0.2-0.4) occupied 6.20, 14.30 and 22.40% of the Tibetan Plateau area, respectively, and the majority (56.40%) of the Tibetan Plateau area constituted a highly unsuitable habitat (HS = 0-0.2). In addition, the response curves of species ecological suitability simulated by generalized additive model nearly corresponded with the response curves generated by the MaxEnt model. Conclusions: At a temporal scale, the habitat suitability of S. purpurea tends to increase from the 1990s to 2050s, but decline from the 2050s to 2070s. At a spatial scale, the future distribution of S. purpurea will not exhibit sweeping changes and will remain in the central and southeastern regions of the Tibetan Plateau. These results benefit the local animal husbandry and provide evidence for establishing reasonable management practices. C1 [Ma, Baibing; Sun, Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, 11A Datun Roadm, Beijing 100101, Peoples R China. [Ma, Baibing] Changan Univ, Sch Earth Sci & Resource, Xian 710000, Shaanxi, Peoples R China. [Sun, Jian] Rutgers State Univ, Dept Ecol Evolut & Nat Resources, Grant Walton Ctr Remote Sensing & Spatial Anal, Sch Environm & Biol Sci, New Brunswick, NJ 08901 USA. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, 11A Datun Roadm, Beijing 100101, Peoples R China.; Sun, J (通讯作者)，Rutgers State Univ, Dept Ecol Evolut & Nat Resources, Grant Walton Ctr Remote Sensing & Spatial Anal, Sch Environm & Biol Sci, New Brunswick, NJ 08901 USA. EM sunjian@igsnrr.ac.cn TC 79 Z9 95 PD FEB 21 PY 2018 VL 18 AR 10 DI 10.1186/s12898-018-0165-0 UT WOS:000425989900001 DA 2023-03-23 ER PT J AU Ganjurjav, H Hu, GZ Wan, YF Li, Y Danjiu, LB Gao, QZ AF Ganjurjav, Hasbagan Hu, Guozheng Wan, Yunfan Li, Yue Danjiu, Luobu Gao, Qingzhu TI Different responses of ecosystem carbon exchange to warming in three types of alpine grassland on the central Qinghai-Tibetan Plateau SO ECOLOGY AND EVOLUTION DT Article AB Climate is a driver of terrestrial ecosystem carbon exchange, which is an important product of ecosystem function. The Qinghai-Tibetan Plateau has recently been subjected to a marked increase in temperature as a consequence of global warming. To explore the effects of warming on carbon exchange in grassland ecosystems, we conducted a whole-year warming experiment between 2012 and 2014 using open-top chambers placed in an alpine meadow, an alpine steppe, and a cultivated grassland on the central Qinghai-Tibetan Plateau. We measured the gross primary productivity, net ecosystem CO2 exchange (NEE), ecosystem respiration, and soil respiration using a chamber-based method during the growing season. The results show that after 3years of warming, there was significant stimulation of carbon assimilation and emission in the alpine meadow, but both these processes declined in the alpine steppe and the cultivated grassland. Under warming conditions, the soil water content was more important in stimulating ecosystem carbon exchange in the meadow and cultivated grassland than was soil temperature. In the steppe, the soil temperature was negatively correlated with ecosystem carbon exchange. We found that the ambient soil water content was significantly correlated with the magnitude of warming-induced change in NEE. Under high soil moisture condition, warming has a significant positive effect on NEE, while it has a negative effect under low soil moisture condition. Our results highlight that the NEE in steppe and cultivated grassland have negative responses to warming; after reclamation, the natural meadow would subject to loose more C in warmer condition. Therefore, under future warmer condition, the overextension of cultivated grassland should be avoided and scientific planning of cultivated grassland should be achieved. C1 [Ganjurjav, Hasbagan; Hu, Guozheng; Wan, Yunfan; Li, Yue; Gao, Qingzhu] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. [Ganjurjav, Hasbagan; Hu, Guozheng; Wan, Yunfan; Li, Yue; Gao, Qingzhu] Minist Agr, Key Lab Agroenvironm, Beijing, Peoples R China. [Danjiu, Luobu] Nagqu Grassland Stn, Nagqu, Tibet Autonomou, Peoples R China. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing, Peoples R China. EM gaoqingzhu@caas.cn TC 20 Z9 22 PD FEB PY 2018 VL 8 IS 3 BP 1507 EP 1520 DI 10.1002/ece3.3741 UT WOS:000423807900007 DA 2023-03-23 ER PT J AU Guo, N Wang, AD Degen, AA Deng, B Shang, ZH Ding, LM Long, RJ AF Guo, Na Wang, Aidong Degen, A. Allan Deng, Bin Shang, Zhanhuan Ding, Luming Long, Ruijun TI Grazing exclusion increases soil CO2 emission during the growing season in alpine meadows on the Tibetan Plateau SO ATMOSPHERIC ENVIRONMENT DT Article AB Soil CO2 emission is a key part of the terrestrial carbon cycle. Grazing exclusion by fencing is often considered a beneficial grassland management option to restore degraded grassland, but its effect on soil CO2 emission on the northeastern Tibetan Plateau is equivocal and is the subject of this study. Using a closed static chamber, we measured diurnal soil CO2 flux weekly from July, 2008, to April, 2009, in response to grazing and grazing exclusion in the alpine meadow and alpine shrub meadow. Concomitantly, soil temperature was measured at depths of 5 cm, 10 cm, 15 cm and 20 cm with digital temperature sensors. It emerged that: 1) non-grazed grasslands emitted more soil CO2 than grazed grasslands over the growing season; 2) the alpine shrub meadow emitted more soil CO2 than the alpine meadow; the annual cumulative soil CO2 emissions of alpine meadow and alpine shrub meadow were 241.5-326.5 g C/m(2) and 429.0-512.5 g C/m(2), respectively; 3) seasonal patterns were evident with more soil CO2 flux in the growing than in the non-growing season; and 4) the diurnal soil CO2 flux exhibited a single peak across all sampling sites. In addition, soil CO2 flux was correlated positively with soil" temperature at 5 cm, but not at the other depths. We concluded that grazing exclusion enhanced soil CO2 emission over the growing season, and decreased carbon sequestration of alpine meadow and alpine shrub meadow on the northeastern Tibetan Plateau. Since an increase in soil temperature increased soil CO2 flux, global warming could have an effect on soil CO2 emission in the future. C1 [Guo, Na; Wang, Aidong; Deng, Bin; Shang, Zhanhuan; Ding, Luming; Long, Ruijun] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Degen, A. Allan] Ben Gurion Univ Negev, Blaustein Inst Desert Res, Wyler Dept Dryland Agr, Desert Anim Adaptat & Husb, IL-8410500 Beer Sheva, Israel. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. EM shangzhh@lzu.edu.cn TC 30 Z9 32 PD FEB PY 2018 VL 174 BP 92 EP 98 DI 10.1016/j.atmosenv.2017.11.053 UT WOS:000423888400009 DA 2023-03-23 ER PT J AU Li, W Wang, JL Zhang, XJ Shi, SL Cao, WX AF Li Wen Wang Jinlan Zhang Xiaojiao Shi Shangli Cao Wenxia TI Effect of degradation and rebuilding of artificial grasslands on soil respiration and carbon and nitrogen pools on an alpine meadow of the Qinghai-Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB The alpine meadow ecosystem on the Qinghai-Tibet Plateau has degenerated greatly in recent decades. The most effective means of restoration for severely degraded grasslands is rebuilding artificial grasslands. However, the effects of converting severely degraded grasslands to artificial grasslands on soil respiration and the relationships between soil respiration and carbon and nitrogen storage remain unclear. Therefore, we evaluated soil respiration and carbon and nitrogen storage on native grasslands with different levels of degradation (no degradation (ND), lightly degraded (LD), moderately degraded (MD) and severely degraded (SD)); the study was on a perennial artificial grassland with different restoration years (cultivated for 3 years (A3) and cultivated for 16 years (A16)) and on an annual oat grassland in an alpine meadow of the Qinghai-Tibet Plateau and applied a structural equation model to explore the relative contributions of biotic and abiotic variables in the regulation of soil respiration. Our results demonstrated that grassland degradation significantly decreased the growing season soil respiration, annual mean soil respiration, vegetation, and the soil and ecosystem carbon and nitrogen storage. Meanwhile, the establishment of annual oat grasslands significantly decreased the growing season soil respiration, annual mean soil respiration, 0-30 cm soil layer and ecosystem carbon and nitrogen storage, whereas it significantly increased the vegetation carbon and nitrogen storage. In contrast, the perennial artificial grassland had no significant effect on the growing season soil respiration or on the annual mean soil respiration but significantly increased the forage yield and ecosystem carbon and nitrogen storage. Grassland degradation and artificial grassland establishment had no significant effect on the dormant season soil respiration. Furthermore, soil moisture had a greater impact on growing season soil respiration, whereas soil temperature had a more significant effect on the dormant season soil respiration. Furthermore, a structural equation model indicated that the carbon storage in the roots and the 0-10 cm soil layer were two important biotic factors that controlled soil respiration. Considering the ecological and productive properties, establishing a perennial artificial grassland could be the best strategy for restoring the black-soil-type grasslands native to the Qinghai-Tibet Plateau. C1 [Li Wen; Wang Jinlan; Shi Shangli; Cao Wenxia] Gansu Agr Univ, Grassland Sci Coll, Res Ctr Sustainable Grassland & Livestock Managem, Grassland Ecosyst Key Lab,Minist Educ,Sino US, Lanzhou 730030, Gansu, Peoples R China. [Zhang Xiaojiao] Anim Husb Prairie Stn Longnan, Longnan 746000, Peoples R China. RP Cao, WX (通讯作者)，Gansu Agr Univ, Grassland Sci Coll, Res Ctr Sustainable Grassland & Livestock Managem, Grassland Ecosyst Key Lab,Minist Educ,Sino US, Lanzhou 730030, Gansu, Peoples R China. EM caowenxia@foxmail.com TC 68 Z9 82 PD FEB PY 2018 VL 111 BP 134 EP 142 DI 10.1016/j.ecoleng.2017.10.013 UT WOS:000419529600015 DA 2023-03-23 ER PT J AU Liu, SB Schleuss, PM Kuzyakov, Y AF Liu, Shibin Schleuss, Per-Marten Kuzyakov, Yakov TI RESPONSES OF DEGRADED TIBETAN KOBRESIA PASTURES TO N ADDITION SO LAND DEGRADATION & DEVELOPMENT DT Article AB Kobresia pastures on the Tibetan Plateau are the largest alpine pastoral ecosystems. Kobresia pastures have experienced severe degradation in recent decades, inducing large nitrogen (N) losses from these ecosystems. This is particularly problematic, as it intensifies prevailing N limitation in these regions. Simultaneously, anthropogenic N deposition has increased across these ecosystems, but the fate of added N on variously degraded Kobresia pastures remains unclear. Kobresia pastures of three degradation stages were investigated: living, dying and dead root mats. High and very low (as a tracer) amounts of N-15-labelled ammonium nitrate (NH4NO3) were applied to root mats under controlled conditions. Leaching was simulated over 3 months, and N-15 recovery was measured in the plant-soil system. N addition promoted aboveground biomass and foliar N content of Kobresia during the early growth period, indicating a short-term offset of N limitation. After 7-8 weeks, plant growth and N-15 uptake were reduced in plants with initial N addition, reflecting a transition to N limitation induced by N uptake and leaching from soil. This limitation was also indicated by the strong decline of NO3- in leachates from living root mats compared with degraded root mats. Leaching N losses from dying and dead root mats increased 22 and 63 times, respectively, compared with those of living root mats. We conclude that N addition can facilitate plant growth in living root mats but contributes to N leaching in degraded pastures. This contribution to N leaching may weaken ecosystem recovery, increase NO3- loading of adjacent lower landscape parts and cause eutrophication of aquatic ecosystems. Copyright (c) 2017 John Wiley & Sons, Ltd. C1 [Liu, Shibin; Schleuss, Per-Marten; Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, Busgenweg 2, D-37077 Gottingen, Germany. [Kuzyakov, Yakov] Univ Gottingen, Dept Agr Soil Sci, Busgenweg 2, D-37077 Gottingen, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan 420049, Russia. RP Liu, SB (通讯作者)，Univ Gottingen, Dept Soil Sci Temperate Ecosyst, Busgenweg 2, D-37077 Gottingen, Germany. EM sliu3@gwdg.de TC 11 Z9 12 PD FEB PY 2018 VL 29 IS 2 BP 303 EP 314 DI 10.1002/ldr.2720 UT WOS:000425100700012 DA 2023-03-23 ER PT J AU Meng, BP Gao, JL Liang, TG Cui, X Ge, J Yin, JP Feng, QS Xie, HJ AF Meng, Baoping Gao, Jinlong Liang, Tiangang Cui, Xia Ge, Jing Yin, Jianpeng Feng, Qisheng Xie, Hongjie TI Modeling of Alpine Grassland Cover Based on Unmanned Aerial Vehicle Technology and Multi-Factor Methods: A Case Study in the East of Tibetan Plateau, China SO REMOTE SENSING DT Article AB Grassland cover and its temporal changes are key parameters in the estimation and monitoring of ecosystems and their functions, especially via remote sensing. However, the most suitable model for estimating grassland cover and the differences between models has rarely been studied in alpine meadow grasslands. In this study, field measurements of grassland cover in Gannan Prefecture, from 2014 to 2016, were acquired using unmanned aerial vehicle (UAV) technology. Single-factor parametric and multi-factor parametric/non-parametric cover inversion models were then constructed based on 14 factors related to grassland cover, and the dynamic variation of the annual maximum cover was analyzed. The results show that (1) nine out of 14 factors (longitude, latitude, elevation, the concentrations of clay and sand in the surface and bottom soils, temperature, precipitation, enhanced vegetation index (EVI) and normalized difference vegetation index (NDVI)) exert a significant effect on grassland cover in the study area. The logarithmic model based on EVI presents the best performance, with an R-2 and RMSE of 0.52 and 16.96%, respectively. Single-factor grassland cover inversion models account for only 1-49% of the variation in cover during the growth season. (2) The optimum grassland cover inversion model is the artificial neural network (BP-ANN), with an R-2 and RMSE of 0.72 and 13.38%, and SDs of 0.062% and 1.615%, respectively. Both the accuracy and the stability of the BP-ANN model are higher than those of the single-factor parametric models and multi-factor parametric/non-parametric models. (3) The annual maximum cover in Gannan Prefecture presents an increasing trend over 60.60% of the entire study area, while 36.54% is presently stable and 2.86% exhibits a decreasing trend. C1 [Meng, Baoping; Gao, Jinlong; Liang, Tiangang; Ge, Jing; Yin, Jianpeng; Feng, Qisheng] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China. [Meng, Baoping; Gao, Jinlong; Liang, Tiangang; Ge, Jing; Yin, Jianpeng; Feng, Qisheng] Lanzhou Univ, Minist Agr, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730020, Gansu, Peoples R China. [Cui, Xia] Lanzhou Univ, Coll Earth & Environm Sci, Minist Educ, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Gansu, Peoples R China. [Xie, Hongjie] Univ Texas San Antonio, Lab Remote Sensing & Geoinformat, San Antonio, TX 78249 USA. RP Liang, TG (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China.; Liang, TG (通讯作者)，Lanzhou Univ, Minist Agr, Key Lab Grassland Livestock Ind Innovat, Lanzhou 730020, Gansu, Peoples R China. EM mengbp09@lzu.edu.cn; rslabjinlong@163.com; tgliang@lzu.edu.cn; xiacui@lzu.edu.cn; gej12@lzu.edu; yinjp2013@lzu.edu.cn; fengqsh@lzu.edu.cn; hongjie.xie@utsa.edu TC 30 Z9 33 PD FEB PY 2018 VL 10 IS 2 AR 320 DI 10.3390/rs10020320 UT WOS:000427542100164 DA 2023-03-23 ER PT J AU Sun, J Ma, BB Lu, XY AF Sun, Jian Ma, Baibing Lu, Xuyang TI Grazing enhances soil nutrient effects: Trade-offs between aboveground and belowground biomass in alpine grasslands of the Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Understanding the impact of grazing patterns on grassland production is of fundamental importance for grassland conservation and management. The objective of this study is to obtain an understanding of the trade-offs between aboveground biomass and belowground biomass, which are influenced by environmental factors in free grazing (FG) and grazing exclusion (GE) alpine grasslands on the Tibetan Plateau. We explored the relationships between the trade-off and environmental factors using correlation analysis, a generalized additive model and a structural equation model, and then found that the key factors that determine trade-off showed differences in FG and GE grasslands and that the final structural equation modeling result explained that 96% (path coefficient=0.96) and 65% (path coefficient=0.65) of the variations in the trade-off were due to FG or GE classifications, respectively. The results demonstrated that soil organic carbon, soil carbon/soil nitrogen, and soil available nitrogen affect the trade-off between aboveground and belowground biomass in FG grasslands more obviously than in GE grasslands. However, the effects of growing season temperature on the trade-off were insignificant, -0.218 and -0.181 in FG and GE grasslands, respectively. FG increased the soil bulk density, which resulted in an alteration in the soil pore size distribution and a greater resistance to root penetration. In addition, FG affected the level of soil nutrition, which will affect the nitrogen mineralization of decomposition and absorption, as well as the root biomass. Consequently, this study can provide guidance to improve the quality of grassland. C1 [Sun, Jian; Ma, Baibing] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. [Ma, Baibing] Changan Univ, Sch Earth Sci & Resource, Xian 710000, Shaanxi, Peoples R China. [Lu, Xuyang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China.; Lu, XY (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China. EM sunjian@igsnrr.ac.cn; xylu@imde.ac.cn TC 71 Z9 84 PD FEB PY 2018 VL 29 IS 2 BP 337 EP 348 DI 10.1002/ldr.2822 UT WOS:000425100700015 DA 2023-03-23 ER PT J AU Wu, XD Zhao, L Hu, GJ Liu, GM Li, WP Ding, YJ AF Wu, Xiaodong Zhao, Lin Hu, Guojie Liu, Guimin Li, Wangping Ding, Yongjian TI Permafrost and land cover as controlling factors for light fraction organic matter on the southern Qinghai-Tibetan plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Permafrost degradation can stimulate the decomposition of organic soil matter and cause a large amount of greenhouse gas emissions into the atmosphere. The light fraction organic matter (LFOM) is a labile substrate for microbial decomposition and probably plays an important role in future permafrost carbon cycles. However, little is known about the distribution of LFOM and its relationship with permafrost and environmental factors. Here, we investigated the light fraction carbon (LFC) and nitrogen (LFN) contents and stocks under meadows and wet meadows with different permafrost conditions on the southern Qinghai-Tibetan Plateau. Our results showed that LFC and LFN were mainly distributed in the upper 30 cm of soils, and the sites with permafrost had significantly higher contents of LFC and LFN than those from the sites without existing permafrost. The LFC and LFN decreased sharplywith depth, suggesting that the soil organicmatter (SOM) in this areawas highly decomposed in deep soils. Soil moisture and bulk density explained approximately 50% of the variances in LFC and LFN for all the sampling sites, while soil moisture explained approximately 30% of the variance in permafrost sites. Both the C:N ratios and LFC: LFN ratios in the sites with permafrost were higher than those in the sites without permafrost. The results suggested that the permafrost and land cover types are the main factors controlling LFOM content and stock, and that permafrost degradation would lead to a decrease of LFOM and soil C: N ratios, thus accelerating the decomposition of SOM. (C) 2017 Elsevier B.V. All rights reserved. C1 [Wu, Xiaodong; Zhao, Lin; Hu, Guojie; Ding, Yongjian] Chinese Acad Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, State Key Lab Cryospher Sci, Northwest Inst Ecoenvironm & Resources, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. [Liu, Guimin] Lanzhou Jiaotong Univ, Sch Environm & Municipal Engn, 88 West Anning Rd, Lanzhou 730070, Gansu, Peoples R China. [Li, Wangping] Lanzhou Univ Technol, Sch Civil Engn, 287 Langonping Rd, Lanzhou 730050, Gansu, Peoples R China. [Ding, Yongjian] Univ Chinese Acad Sci, 19 A Yuquan Rd, Beijing 100049, Peoples R China. RP Zhao, L (通讯作者)，320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. EM linzhao@lzb.ac.cn TC 33 Z9 39 PD FEB 1 PY 2018 VL 613 BP 1165 EP 1174 DI 10.1016/j.scitotenv.2017.09.052 UT WOS:000414160500117 DA 2023-03-23 ER PT J AU Zhang, SY Li, XY AF Zhang, Si-Yi Li, Xiao-Yan TI Soil moisture and temperature dynamics in typical alpine ecosystems: a continuous multi-depth measurements-based analysis from the Qinghai-Tibet Plateau, China SO HYDROLOGY RESEARCH DT Article AB Soil temperature and moisture are the key variables that control the overall effect of climate and topography on soil and vegetation in alpine regions. However, there has been little investigation of the potential soil temperature and moisture feedbacks on climate changes in different alpine ecosystems and their impact on vegetation change. Soil temperature and moisture at five depths were measured continuously at 10-min intervals in three typical ecosystems (Kobresia meadow (KMd), Achnatherum splendens steppe (ASSt), and Potentilla fruticosa shrub (PFSh)) of the Qinghai Lake watershed on the northeast Qinghai-Tibet Plateau, China. The findings of this study revealed that the KMd and PFSh sites had relatively low soil temperature and high soil moisture, whereas the ASSt site had relatively warm soil temperature and low soil moisture. The soil and vegetation characteristics had important effects on the infiltration process and soil moisture regime; about 47%, 87%, and 34% of the rainfall (minus interception) permeated to the soil in the KMd, PFSh, and ASSt sites, respectively. In the context of the warming climate, changes to soil moisture and temperature are likely to be the key reasons of the alpine meadow deterioration and the alpine shrub expansion in the alpine regions. C1 [Zhang, Si-Yi; Li, Xiao-Yan] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Zhang, Si-Yi; Li, Xiao-Yan] Beijing Normal Univ, Fac Geog Sci, Sch Nat Resources, Beijing 100875, Peoples R China. [Zhang, Si-Yi] Guangdong Inst Ecoenvironm Sci & Technol, Guangdong Key Lab Agr Environm Pollut Integrated, Guangzhou 510650, Guangdong, Peoples R China. RP Li, XY (通讯作者)，Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China.; Li, XY (通讯作者)，Beijing Normal Univ, Fac Geog Sci, Sch Nat Resources, Beijing 100875, Peoples R China. EM xyli@bnu.edu.cn TC 26 Z9 27 PD FEB PY 2018 VL 49 IS 1 BP 194 EP 209 DI 10.2166/nh.2017.215 UT WOS:000429613800014 DA 2023-03-23 ER PT J AU Xu, B Wang, JN Wu, N Wu, Y Shi, FS AF Xu, Bo Wang, Jinniu Wu, Ning Wu, Yan Shi, Fusun TI Seasonal and interannual dynamics of soil microbial biomass and available nitrogen in an alpine meadow in the eastern part of Qinghai-Tibet Plateau, China SO BIOGEOSCIENCES DT Article AB Soil microbial activity varies seasonally in frozen alpine soils during cold seasons and plays a crucial role in available N pool accumulation in soil. The intra- and interannual patterns of microbial and nutrient dynamics reflect the influences of changing weather factors, and thus provide important insights into the biogeochemical cycles and ecological functions of ecosystems. We documented the seasonal and interannual dynamics of soil microbial and available N in an alpine meadow in the eastern part of Qinghai-Tibet Plateau, China, between April 2011 and October 2013. Soil was collected in the middle of each month and analyzed for water content, microbial biomass C (MBC) and N (MBN), dissolved organic C and N, and inorganic N. Soil microbial community composition was measured by the dilutionplate method. Fungi and actinomycetes dominated the microbial community during the nongrowing seasons, and the proportion of bacteria increased considerably during the early growing seasons. Trends of consistently increasing MBC and available N pools were observed during the nongrowing seasons. MBC sharply declined during soil thaw and was accompanied by a peak in available N pool. Induced by changes in soil temperatures, significant shifts in the structures and functions of microbial communities were observed during the winter-spring transition and largely contributed to microbial reduction. The divergent seasonal dynamics of different N forms showed a complementary nutrient supply pattern during the growing season. Similarities between the interannual dynamics of microbial biomass and available N pools were observed, and soil temperature and water conditions were the primary environmental factors driving interannual fluctuations. Owing to the changes in climate, seasonal soil microbial activities and nutrient supply patterns are expected to change further, and these changes may have crucial implications for the productivity and biodiversity of alpine ecosystems. C1 [Xu, Bo; Wang, Jinniu; Wu, Ning; Wu, Yan; Shi, Fusun] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Sichuan, Peoples R China. [Xu, Bo] Aba Teachers Univ, Coll Resources & Environm, Aba 623002, Sichuan, Peoples R China. [Wang, Jinniu; Wu, Ning; Wu, Yan; Shi, Fusun] Chinese Acad Sci, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Sichuan, Peoples R China. [Wang, Jinniu; Wu, Ning; Wu, Yan; Shi, Fusun] Chinese Acad Sci, Ecol Restorat Biodivers Conservat Key Lab Sichuan, Chengdu 610041, Sichuan, Peoples R China. RP Shi, FS (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Sichuan, Peoples R China.; Shi, FS (通讯作者)，Chinese Acad Sci, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Sichuan, Peoples R China.; Shi, FS (通讯作者)，Chinese Acad Sci, Ecol Restorat Biodivers Conservat Key Lab Sichuan, Chengdu 610041, Sichuan, Peoples R China. EM shifs@cib.ac.cn TC 14 Z9 17 PD JAN 29 PY 2018 VL 15 IS 2 BP 567 EP 579 DI 10.5194/bg-15-567-2018 UT WOS:000423506700003 DA 2023-03-23 ER PT J AU Liu, SB Zamanian, K Schleuss, PM Zarebanadkouki, M Kuzyakov, Y AF Liu, Shibin Zamanian, Kazem Schleuss, Per-Marten Zarebanadkouki, Mohsen Kuzyakov, Yakov TI Degradation of Tibetan grasslands: Consequences for carbon and nutrient cycles SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Review AB The Tibetan Plateau hosts the world's largest alpine pastoral ecosystems, dominated by the endemic sedges Kobresia pygmaea and Kobresia humilis. Owing to the very harsh environment and also to soil nitrogen (N) and phosphorus (P) limitations, these pastoral ecosystems are very sensitive to disturbances (e.g. anthropogenic activities and climate change) and recover extremely slowly. Overgrazing on the Tibetan Plateau has caused severe degradation of vegetation and soils in the last 30-50 years. For the first time, for Kobresia pastures in Tibetan Plateau, we have summarized and generalized the consequences of pasture degradation for soil organic carbon (SOC) and nutrient (N, P) stocks, and evaluated the main biotic and abiotic mechanisms of their loss. Based on 44 literature studies as well as own data, we demonstrated that 42% of SOC stocks were lost, relative to non-degraded pastures. These SOC losses are similar to the decreases in N stocks (-33%), and aboveground (-42%) and belowground (-45%) plant biomass. Although P losses are lower (-17%), its precipitation reduces its availability for plants. These losses are in fact underestimates, since undisturbed natural sites no longer exist on the Tibetan Plateau. The losses are much higher in the upper 10 cm and in some areas extend to complete removal of soil cover. This has dramatic repercussions for local livestock, human populations and river pollution. While some rehabilitation projects have shown positive outcomes, the complete recovery of degraded pastures (e.g. soil fertility, ecosystem stability) is infeasible, because of very slow pedogenic processes, slow vegetation restoration, as well as continuously increasing anthropogenic pressure and climate change. Considering the rapid losses of SOC and nutrients, and the very slow recovery potential, Tibetan pastures in some regions may disappear in the next few decades without proper and effective recovery strategies. C1 [Liu, Shibin; Schleuss, Per-Marten; Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, Gottingen, Germany. [Zamanian, Kazem; Kuzyakov, Yakov] Univ Gottingen, Dept Agr Soil Sci, Gottingen, Germany. [Zarebanadkouki, Mohsen] Univ Gottingen, Div Soil Hydrol, Gottingen, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan 420049, Russia. RP Liu, SB (通讯作者)，Chengdu Univ Technol, Coll Earth Sci, Chengdu 610059, Sichuan, Peoples R China. EM sliu3@gwdg.de TC 159 Z9 179 PD JAN 15 PY 2018 VL 252 BP 93 EP 104 DI 10.1016/j.agee.2017.10.011 UT WOS:000416616100011 DA 2023-03-23 ER PT J AU Cao, YF Ke, X Guo, XW Cao, GM Du, YO AF Cao Yingfang Ke Xun Guo Xiaowei Cao Guangmin Du Yangong TI Nitrous Oxide Emission Rates over 10 Years in an Alpine Meadow on the Tibetan Plateau SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES DT Article AB The alpine grassland ecosystem covering about 85% of the Tibetan plateau is fragile and sensitive to natural and anthropogenic disturbances. However, it is unclear how nitrous oxide (N2O) has varied over the last 10 years. In order to accurately estimate the regional N2O emissions budget, the N2O levels, environmental factors, and biomass were investigated on a yearly, monthly, and seasonal basis from 2000 to 2014 in an alpine meadow. The results showed that there was an overall declining trend in emissions over 10 years, during which the two maximum emission rates were 64.8 +/- 11.1 and 41.8 +/- 18.2 mu g m(-2) h(-1) (in 2001 and 2006). The average N2O emissions rate was about 38.4 +/- 3.3 mu g m(-2) h(-1). Pearson correlation demonstrated that soil and air temperature exerted a crucial influence on N2O, followed by precipitation and aboveground biomass, but the effect of soil moisture at a depth of 10 cm was negative. Multiple linear regressions showed a good relationship between N2O and all environmental factors. Future scenarios of wetter and warmer weather would noticeably increase alpine meadow N2O emissions on the Tibetan Plateau. C1 [Cao Yingfang; Ke Xun; Guo Xiaowei; Cao Guangmin; Du Yangong] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat & Ecol Cold Reg Qinghai, Xining, Qinghai, Peoples R China. [Cao Yingfang; Ke Xun] Univ Chinese Acad Sci, Beijing, Peoples R China. RP Du, YO (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Restorat & Ecol Cold Reg Qinghai, Xining, Qinghai, Peoples R China. EM ygdu@nwipb.cas.cn TC 3 Z9 4 PY 2018 VL 27 IS 3 BP 1353 EP 1358 DI 10.15244/pjoes/76795 UT WOS:000427520400041 DA 2023-03-23 ER PT J AU Ci, P Xu, M AF Ci, Ping Xu, Min TI PATTERNS AND DYNAMICS OF DEGRADATION INDUCED GRASSLAND PRODUCTIVITY CHANGE IN TIBET SO FRESENIUS ENVIRONMENTAL BULLETIN DT Article AB Direction and magnitude of the productivity change concerning grassland degradation in the Tibetan grassland was inconsistently estimated and discussed. The assumption frameworks were debatable. Here we adopted net primary production (NPP) as an indicator, estimated degradation induced grassland productivity change (NPPd) during 2000-2015, based on potential NPP (NPPpot, simulated by the Terrestrial Ecosystem Model), NPP remaining in the ecosystem (NPPeco, based on remote sensing product) and human consumed NPP (NPPh, NPP consumed by livestock). Then, we further examined the correlation between NPPd and other NPP indicators as well as climatic variables, explored the dynamics of detailed livestock husbandry data - sheep and cattle stocks, sheep meat and beef production. The results show that NPPd decreased in the majority areas of the Tibetan grassland during the study period, suggested a recovery of grassland degradation, even under the circumstance of a decreasing NPPpot and an increasing NPPh. This should be the combination effect of ecological conservation policies and local economic developments. These findings provide a quantitative discuss on the patterns and dynamics of grassland degradation in the unique Tibetan grassland under complicated socio-economic developments and conservation polices, that could further contribute to evaluation and optimization of local sustainable ecosystem management. C1 [Ci, Ping; Xu, Min] Inst Forest Inventory Planning & Res Tibet Autono, West Jinzhu Rd 74, Chengguan Dist 850000, Lhasa, Peoples R China. RP Xu, M (通讯作者)，Inst Forest Inventory Planning & Res Tibet Autono, West Jinzhu Rd 74, Chengguan Dist 850000, Lhasa, Peoples R China. EM xumin19900605@163.com TC 1 Z9 1 PY 2018 VL 27 IS 8 BP 5619 EP 5628 UT WOS:000444528000053 DA 2023-03-23 ER PT J AU Guan, S An, N Zong, N He, YT Shi, P Zhang, JJ He, NP AF Guan, Song An, Na Zong, Ning He, Yongtao Shi, Peili Zhang, Jinjing He, Nianpeng TI Climate warming impacts on soil organic carbon fractions and aggregate stability in a Tibetan alpine meadow SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB Alpine meadows in the Tibetan Plateau contain a large amount of soil organic carbon (SOC), which is highly vulnerable to climate change and has thus been a research priority for scientists in recent decades. However, how climate warming influences the composition and stability of SOC remains unclear. In this study, a warming experiment (20102015) using open-top chambers was established (with unwarmed control [CK], winter warming [WW], and year-round warming [YW]) to investigate the effects of warming on the contents of SOC and its fractions, chemical composition of SOC, and water stability of aggregates in an alpine meadow located at the Damxung Grassland Station in the northern Tibetan Plateau. Experimental warming had no apparent effect (p > 0.05) on SOC content (17.8 +/- 1.96, 17.8 +/- 1.13 and 17.8 +/- 1.09 g kg(-1) under CK, WW and YW, respectively) in the 020 cm soil layer. However, warming significantly (p < 0.05) increased soil water-soluble organic carbon (C) content by 46.2% and 69.2%under WW and YW, respectively, and affected SOC chemical composition with decreasing phenol C (by 2.6% under WW, p > 0.05; and 8.4% under YW, p < 0.05) and increasing carboxyl C (by 11.6% under WW, p < 0.05; and 5.0% under YW, p > 0.05). Warming decreased (p > 0.05) the proportions of macroaggregates (20.25 mm) and free microaggregates (0.250.053 mm), whereas warming significantly increased the proportion of non-aggregated silt- and clay-sized fractions (<0.053 mm) by 41.0% and 55.7% under WW and YW, respectively. The variation in the aggregate size distribution resulted in the decline of the mean weight diameter and geometric mean diameter of water-stable aggregates by 5.1% (p > 0.05) and 8.5% (p < 0.05) under WW and by 8.5% and 6.6% (both p < 0.05) under YW, respectively. Of importance, the organic C content in free microaggregates, which provides greater physical protection to stabilize SOC, decreased by 10.9% (p > 0.05) under WW and by 22.4% (p < 0.05) under YW. The organic C contents of particulate organic matter and silt- and clay-sized fractions inside free microaggregates also significantly decreased under YW by 49.4% and 16.9%, respectively. However, the organic C content in non-aggregated silt- and clay-sized fractions significantly increased under WW and YW by 52.9% and 46.8%, respectively. The results suggest that short-term climate warming did not affect total SOC stocks, whereas it had a positive effect on WSOC, carboxyl C and non-aggregated silt- and clay-associated C and exhibited a negative effect on phenol C, free microaggregates-associated C and water stability of aggregates. These variables may act as sensitive indicators of climate warming in the Tibetan alpine meadows, which will in turn affect grassland ecosystem C fluxes in response to further climate change. The findings of the present study help improve our understanding of the responses of terrestrial ecosystem C cycling to future climate change. C1 [Guan, Song; An, Na; Zhang, Jinjing] Jilin Agr Univ, Key Lab Soil Resource Sustainable Utilizat Commod, Coll Resource & Environm Sci, Changchun 130118, Jilin, Peoples R China. [Zong, Ning; He, Yongtao; Shi, Peili; He, Nianpeng] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [He, Nianpeng] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [He, Nianpeng] Northeast Normal Univ, Inst Grassland Sci, Key Lab Vegetat Ecol, Minist Educ, Changchun 130024, Jilin, Peoples R China. RP Zhang, JJ (通讯作者)，Jilin Agr Univ, Key Lab Soil Resource Sustainable Utilizat Commod, Coll Resource & Environm Sci, Changchun 130118, Jilin, Peoples R China.; He, NP (通讯作者)，Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM zhangjinjing@126.com; henp@igsnrr.ac.cn TC 84 Z9 107 PD JAN PY 2018 VL 116 BP 224 EP 236 DI 10.1016/j.soilbio.2017.10.011 UT WOS:000419417900026 DA 2023-03-23 ER PT J AU Pang, XP Guo, ZG AF Pang, Xiao Pan Guo, Zheng Gang TI Response of leaf traits of common plants in alpine meadow to plateau pika disturbance SO RANGELAND JOURNAL DT Article AB Leaf traits have been proven to reflect the adaptation of individual plants to disturbance environments in a grassland ecosystem. A field survey was conducted to investigate the effects of the disturbance intensity of plateau pika on the leaf traits of a dominant (Kobresia pygmaea) and two common plants (Elymus nutans and Anemone rivularis var. flore-minore) in an alpine meadow. This study indicated that the plateau pika disturbance enables the individuals of three plants to exhibit respective plasticity because the three plants had different leaf indices (LI) as the disturbance intensity increased. K. pygmaea, E. nutans and A. rivularis var. flore-minore had high specific leaf area (SLA), leaf dry mass content (LDMC), and leaf nitrogen content (LNC) at relatively low, moderate, and high disturbance intensities of plateau pika, respectively. K. pygmaea, E. nutans and A. rivularis var. flore-minore suffered low nutrient stress at low, moderate and high disturbance intensities due to high N: P at corresponding disturbance intensities. These results indicated that K. pygmaea, E. nutans and A. rivularis var. flore-minore grew well at relatively low, moderate, and high disturbance intensity conditions, respectively, which contributed to the improvement of alpine meadows with a higher proportion of E. nutans at a moderate disturbance intensity or the deterioration of alpine meadows with a higher proportion of A. rivularis var. flore-minore at a high disturbance intensity. Our findings suggest that leaf traits are effective tools to explain how small burrowing herbivore disturbances often lead to the improvement or deterioration of alpine meadows under different disturbance intensities. C1 [Pang, Xiao Pan; Guo, Zheng Gang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, State Key Lab Grassland Agroecosyst,Minist Agr, Lanzhou 730020, Gansu, Peoples R China. RP Guo, ZG (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Key Lab Grassland Livestock Ind Innovat, State Key Lab Grassland Agroecosyst,Minist Agr, Lanzhou 730020, Gansu, Peoples R China. EM guozhg@lzu.edu.cn TC 3 Z9 3 PY 2018 VL 40 IS 1 BP 39 EP 46 DI 10.1071/RJ17089 UT WOS:000428045400005 DA 2023-03-23 ER PT J AU Song, Y Jin, L Wang, HB AF Song, Yi Jin, Long Wang, Haibo TI Vegetation Changes along the Qinghai-Tibet Plateau Engineering Corridor Since 2000 Induced by Climate Change and Human Activities SO REMOTE SENSING DT Article AB The Qinghai-Tibet (QT) Plateau Engineering Corridor is located in the hinterland of the QT Plateau, which is highly sensitive to global climate change. Climate change causes permafrost degradation, which subsequently affects vegetation growth. This study focused on the vegetation dynamics and their relationships with climate change and human activities in the region surrounding the QT Plateau Engineering Corridor. The vegetation changes were inferred by applying trend analysis, the Mann-Kendall trend test and abrupt change analysis. Six key regions, each containing 40 nested quadrats that ranged in size from 500 x 500 m to 20 x 20 km, were selected to determine the spatial scales of the impacts from different factors. Cumulative growing season integrated enhanced vegetation index (CGSIEVI) values were calculated for each of the nested quadrats of different sizes to indicate the overall vegetation state over the entire year at different spatial scales. The impacts from human activities, a sudden increase in precipitation and permafrost degradation were quantified at different spatial scales using the CGSIEVI values and meteorological data based on the double mass curve method. Three conclusions were derived. First, the vegetation displayed a significant increasing trend over 23.6% of the study area. The areas displaying increases were mainly distributed in the Hoh Xil. Of the area where the vegetation displayed a significant decreasing trend, 72.4% was made up of alpine meadows. Second, more vegetation, especially the alpine meadows, has begun to degenerate or experience more rapid degradation since 2007 due to permafrost degradation and overgrazing. Finally, an active layer depth of 3 m to 3.2 m represents a limiting depth for alpine meadows. C1 [Song, Yi] Chinese Acad Sci, Inst Earth Environm, State Key Lab Loess & Quaternary Geol, Xian 710061, Shaanxi, Peoples R China. [Jin, Long] CCCC First Highway Consultants Co Ltd, Minist Transport, Key Lab Highway Construct & Maintenance Technol P, Xian 710065, Shaanxi, Peoples R China. [Wang, Haibo] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. RP Song, Y (通讯作者)，Chinese Acad Sci, Inst Earth Environm, State Key Lab Loess & Quaternary Geol, Xian 710061, Shaanxi, Peoples R China.; Jin, L (通讯作者)，CCCC First Highway Consultants Co Ltd, Minist Transport, Key Lab Highway Construct & Maintenance Technol P, Xian 710065, Shaanxi, Peoples R China. EM songyi@ieecas.cn; jinl@ccroad.com.cn; whb@lzb.ac.cn TC 46 Z9 60 PD JAN PY 2018 VL 10 IS 1 AR 95 DI 10.3390/rs10010095 UT WOS:000424092300094 DA 2023-03-23 ER PT J AU Yang, ZN Zhu, QA Zhan, W Xu, YY Zhu, EX Gao, YH Li, SQ Zheng, QY Zhu, D He, YX Peng, CH Chen, H AF Yang, Zhenan Zhu, Qiuan Zhan, Wei Xu, Yingyi Zhu, Erxiong Gao, Yongheng Li, Shiqing Zheng, Qunying Zhu, Dan He, Yixin Peng, Changhui Chen, Huai TI The linkage between vegetation and soil nutrients and their variation under different grazing intensities in an alpine meadow on the eastern Qinghai-Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB The grassland degradation caused by overgrazing is the result of imbalance of energy flow and material cycle under grazing pressure in the ecosystem, and numerous ecological restoration and ecological engineering techniques widely used to restore some ecosystem. However, little research known focused on the relationship (energy flow and material cycle) between plant and soil under different grazing intensity, especially at the rhizosphere which is the most powerful area of plant and soil interaction. In this research we conducted a 5-year grazing experiment including 4 different grazing intensities (no grazing, UG; light grazing, LG; moderate grazing, MG; and heavy grazing, HG) in an alpine meadow on the northeastern margin of Qinghai-Tibetan Plateau (QTP). Plants and soil materials were sampled in July 2015, and to examine the nutrients concentration and ecological stoichiometric of vegetation and soil, the soil microbial biomass and activity, as well as their relationship with vegetation and soil characteristics. We found that grazing increased vegetation and soil nutrient concentrations and increased the ratio of microbial biomass carbon (MBC) to microbial biomass nitrogen (MBC), but the grazing intensity did not significantly influence the nutrients enrichment ratio of rhizosphere soil. There was significant relationship between total carbon (TC) concentration of vegetation and soil, and between vegetation total phosphorus (TP) and soil PO43--P concentration. These results suggested that vegetation and soil nutrient concentrations respond differently to the grazing intensity. Coupling relationship exists in specific nutrients of vegetation and soil and rhizosphere is a powerful tool to understanding the linkage between plant and soil. C1 [Yang, Zhenan; Zhu, Qiuan; Zhan, Wei; Xu, Yingyi; Zhu, Erxiong; Li, Shiqing; Peng, Changhui; Chen, Huai] Northwest A&F Univ, Coll Forestry, Ctr Ecol Forecasting & Global Change, Yangling 712100, Shaanxi, Peoples R China. [Yang, Zhenan; Zhan, Wei; Xu, Yingyi; Zhu, Erxiong; Zhu, Dan; He, Yixin; Chen, Huai] Chinese Acad Sci, Chengdu Inst Biol, CAS Key Lab Mt Ecol Restorat & Bioresource Utiliz, Chengdu 610041, Sichuan, Peoples R China. [Yang, Zhenan; Zhan, Wei; Xu, Yingyi; Zhu, Erxiong; Zhu, Dan; He, Yixin; Chen, Huai] Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat & Biodivers Conservat Key Lab Sichu, Chengdu 610041, Sichuan, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Sichuan, Peoples R China. [Zheng, Qunying] Sichuan Acad Grassland Sci, Chengdu 611731, Sichuan, Peoples R China. [Peng, Changhui] Univ Quebec, Dept Biol Sci, Inst Environm Sci, Montreal, PQ C3H 3P8, Canada. RP Chen, H (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, CAS Key Lab Mt Ecol Restorat & Bioresource Utiliz, Chengdu 610041, Sichuan, Peoples R China.; Chen, H (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat & Biodivers Conservat Key Lab Sichu, Chengdu 610041, Sichuan, Peoples R China. EM chenhuai@cib.ac.cn TC 40 Z9 49 PD JAN PY 2018 VL 110 BP 128 EP 136 DI 10.1016/j.ecoleng.2017.11.001 UT WOS:000417048500014 DA 2023-03-23 ER PT J AU Cui, SJ Meng, FD Ji, SN Qi, W Li, BW Liu, PP Renzeng, WM Lv, WW Jiang, LL Zhang, LR Li, XE Li, YM Zhang, ZH Luo, CY Tsechoe, D Wang, SP AF Cui, Shujuan Meng, Fandong Ji Suonan Qi Wang Li, Bowen Liu, Peipei Renzeng, Wangmu Lv, Wangwang Jiang, Lili Zhang, Lirong Li, Xine Li, Yaoming Zhang, Zhenhua Luo, Caiyun Tsechoe, Dorji Wang, Shiping TI Responses of phenology and seed production of annual Koenigia islandica to warming in a desertified alpine meadow SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB The distribution of annual plant species greatly expands with degradation and desertification of natural grass-lands caused by climate change and overgrazing. However, limited understanding of how their life history traits respond to climate change limits our ability to predict their adaptive strategies in the future. Here we explored effects of warming on phenological sequences and seed production of annual Koenigia islandica using an open top chamber on the Tibetan plateau from 2014 to 2016. Our results indicate that warming significantly delayed first budding-set and complete leaf coloring, and prolonged the durations of leaf coloring and the total activity period in the alpine region. Warming significantly reduced ratio of reproductive and vegetative phases relative to no warming in 2016. Warming significantly increased plant height at first flowering, seed number and mass, but had no significant effect on seed size in 2016. There was a positive correlation between seed germination time and seed number, and there were negative correlations between seed size and first fruiting-set and flowering duration. Soil temperatures and soil moisture in May and June had positive and negative correlations with seed number and mass per plant, respectively. Our results suggest that the annual plant primarily promotes its fitness through an increase in seed number and mass per plant due to an increase in plant height, rather than by altering phenophases or prolong duration of reproductive phase under future warming in the alpine meadow. C1 [Cui, Shujuan; Meng, Fandong; Ji Suonan; Qi Wang; Li, Bowen; Liu, Peipei; Renzeng, Wangmu; Lv, Wangwang; Jiang, Lili; Zhang, Lirong; Li, Xine; Li, Yaoming; Tsechoe, Dorji; Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. [Zhang, Zhenhua; Luo, Caiyun] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Qinghai, Peoples R China. [Tsechoe, Dorji; Wang, Shiping] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Wang, Shiping] Tibet Univ, Naqu Integrated Observat & Res Stn Ecol & Environ, Lasa 850012, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lasa 850012, Peoples R China. [Cui, Shujuan; Qi Wang; Li, Bowen; Liu, Peipei; Renzeng, Wangmu; Lv, Wangwang] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. EM wangsp@itpcas.ac.cn TC 15 Z9 19 PD DEC 15 PY 2017 VL 247 BP 376 EP 384 DI 10.1016/j.agrformet.2017.08.034 UT WOS:000416186700035 DA 2023-03-23 ER PT J AU Mu, CC Zhang, TJ Zhao, Q Su, H Wang, SF Cao, B Peng, XQ Wu, QH Wu, XD AF Mu, Cuicui Zhang, Tingjun Zhao, Qian Su, Hang Wang, Shufa Cao, Bin Peng, Xiaoqing Wu, Qinghai Wu, Xiaodong TI Permafrost affects carbon exchange and its response to experimental warming on the northern Qinghai-Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Warming will increase the carbon flux in permafrost regions, and this process may be linked with permafrost via soil hydrothermal conditions. We measured the ecosystem respiration rates (ERRs) of alpine wet meadow, alpine meadow, and alpine steppe monthly during the growing seasons in 2014 and 2016 on the northern Qinghai Tibetan Plateau (QTP). The results showed that the temperature sensitivity (Q(10)) values of the ERR in alpine wet meadow and alpine meadow were higher than those in alpine steppe. The permafrost table is significantly correlated with soil temperature and moisture, thus, affects the ERRS in these ecosystems. After a 2-year warming experiment using open-top chambers (OTCs), the change rates of ERR (35.0-35.2%) were higher than those of gross primary production (GPP) (27.5-30.3%), while the absolute changes of GPP were greater than ERR. The average daytime NEE decreased by 16.5% to 21.3%, indicating more carbon assimilation was enhanced by the experimental warming. Our results show that ecosystem respiration rates in meadow and wet meadow are more sensitive to temperature increasing than those in steppe. The meadow and wet meadow ecosystems in permafrost regions on the northern QTP will assimilate more carbon than steppe in the growing seasons under climate warming scenarios.s C1 [Mu, Cuicui; Zhang, Tingjun; Zhao, Qian; Su, Hang; Wang, Shufa; Cao, Bin; Peng, Xiaoqing] Lanzhou Univ, MOE, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Gansu, Peoples R China. [Mu, Cuicui; Wu, Xiaodong] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryosphere Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, Lanzhou 730000, Gansu, Peoples R China. [Wu, Qinghai] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. RP Zhang, TJ (通讯作者)，Lanzhou Univ, MOE, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Gansu, Peoples R China.; Wu, XD (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryosphere Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, Lanzhou 730000, Gansu, Peoples R China. EM tjzhang@lzu.edu.cn; wxd565@163.com TC 30 Z9 38 PD DEC 15 PY 2017 VL 247 BP 252 EP 259 DI 10.1016/j.agrformet.2017.08.009 UT WOS:000416186700023 DA 2023-03-23 ER PT J AU Cao, J Gong, Y Yeh, ET Holden, NM Adamowski, JF Deo, RC Liu, M Zhou, J Zhang, J Zhang, W Zhang, S Sheng, D Yang, S Xu, X Li, M Feng, Q AF Cao, J. Gong, Y. Yeh, E. T. Holden, N. M. Adamowski, J. F. Deo, R. C. Liu, M. Zhou, J. Zhang, J. Zhang, W. Zhang, S. Sheng, D. Yang, S. Xu, X. Li, M. Feng, Q. TI Impact of grassland contract policy on soil organic carbon losses from alpine grassland on the Qinghai-Tibetan Plateau SO SOIL USE AND MANAGEMENT DT Article AB Carbon storage in the soils on the Qinghai-Tibetan Plateau plays a very important role in the global carbon budget. In the 1990s, a policy of contracting collective grasslands to smaller units was implemented, resulting in a change from the traditional collective grassland management to two new management patterns: a multi-household management pattern (MMP: grassland shared by several households without enclosures) and a single-household management pattern (SMP: grassland enclosed and used by only one household). In 2016, 50 MMP and 54 SMP winter pastures on the Qinghai-Tibetan Plateau were sampled to assess the differences in soil organic carbon (SOC) between the two management patterns. Results showed that average SOC was significantly greater under MMP than under SMP, with an estimated 0.41 MgC/ha/yr lost due to SMP following the new grassland contract. Based on the government's grassland policy, four grassland utilization scenarios were developed for both summer and winter pastures. We found that if the grassland were managed under SMP, likely C losses ranged between 0.31x10(7) and 6.15x10(7) Mg C/yr across the Qinghai-Tibetan Plateau relative to MMP, which more closely resembles pre-1990s grassland management. Previous estimates of C losses have only considered land use change (with cover change) and ignored the impacts driven by land management pattern changes (without cover change). The new data suggest that C losses from the Qinghai-Tibetan Plateau are greater than previously estimated, and therefore that the grassland contract policy should be reviewed and SMP households should be encouraged to reunite into the MMP. These findings have potential implications for land management strategies not only on the Qinghai-Tibetan Plateau but also other grazing regions globally where such practices may exist. C1 [Cao, J.; Gong, Y.; Liu, M.; Zhou, J.; Zhang, J.; Sheng, D.; Yang, S.; Xu, X.; Li, M.] Northwest Normal Univ, Coll Geog & Environm Sci, Lanzhou 730070, Gansu, Peoples R China. [Yeh, E. T.] Univ Colorado Boulder, Dept Geog, Campus Box 260, Boulder, CO 80309 USA. [Holden, N. M.] Univ Coll Dublin, Sch Biosyst & Food Engn, Agr & Food Sci Ctr, Dublin 4, Ireland. [Adamowski, J. F.] McGill Univ, Dept Bioresource Engn, Fac Agr & Environm Sci, Quebec City, PQ H9X 3V9, Canada. [Deo, R. C.] Univ Southern Queensland, Inst Agr & Environm, Sch Agr Computat & Environm Sci, Int Ctr Appl Climate Sci, Springfield, Qld 4300, Australia. [Deo, R. C.; Feng, Q.] Chinese Acad Sci, Cold & Arid Reg Environm Engn Res Inst, Key Lab Ecohydrol Inland River Basin, Alashan Desert Ecohydrol Expt Res Stn, Lanzhou 73000, Gansu, Peoples R China. [Zhang, W.] Northwest Normal Univ, Coll Chem Engn, Lanzhou 730070, Gansu, Peoples R China. [Zhang, S.] Northwest Normal Univ, Coll Life Sci, Lanzhou 730070, Gansu, Peoples R China. RP Feng, Q (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm Engn Res Inst, Key Lab Ecohydrol Inland River Basin, Alashan Desert Ecohydrol Expt Res Stn, Lanzhou 73000, Gansu, Peoples R China. EM qifeng@lzb.ac.cn TC 17 Z9 21 PD DEC PY 2017 VL 33 IS 4 BP 663 EP 671 DI 10.1111/sum.12387 UT WOS:000418422500018 DA 2023-03-23 ER PT J AU Che, RX Wang, F Wang, WJ Zhang, J Zhao, X Rui, YC Xu, ZH Wang, YF Hao, YB Cui, XY AF Che, Rongxiao Wang, Fang Wang, Weijin Zhang, Jing Zhao, Xing Rui, Yichao Xu, Zhihong Wang, Yanfen Hao, Yanbin Cui, Xiaoyong TI Increase in ammonia-oxidizing microbe abundance during degradation of alpine meadows may lead to greater soil nitrogen loss SO BIOGEOCHEMISTRY DT Article AB Alpine meadows on the Tibetan Plateau have experienced severe degradation in recent decades. Although the effects of alpine meadow degradation on soil properties have been well documented, there is still a paucity of knowledge regarding the responses of nitrogen-cycling microbes (NCMs) to degradation and their links to the changes in soil properties. Here, we systematically determined the effects of degraded patch formation on soil properties (i.e., total carbon, total nitrogen, ammonium nitrogen, nitrate nitrogen, available phosphorus, dissolved organic carbon, moisture, delta N-15, delta C-13, and pH) and NCMs (based on nifH, amoA, narG, nirK, and nirS genes and their transcripts) across three Tibetan alpine meadows at different degradation stages. Results showed that compared to the original grassed patches, the contents of most soil nutrients (e.g., carbon, nitrogen, and phosphorus) were significantly decreased in the degraded patches across the study sites. Degraded patches also tended to have higher soil delta N-15 values and nitrate contents. Among the aforementioned NCMs, soil diazotrophs and denitrifiers only showed weak responses to the patch formation, while ammonia-oxidizing microbes showed the highest consistency and sensitivity in response to the patch formation across the study sites. The abundance of amoA gene and archaeal amoA mRNA significantly increased in the degraded patches, and they were positively correlated with soil delta N-15 values and nitrate nitrogen contents, but negatively correlated with soil total nitrogen and inorganic nitrogen contents. These results suggest that the increased ammonia-oxidizing microbial abundance may be an important driver of soil nitrogen loss during degraded patch formation in alpine meadows. C1 [Che, Rongxiao; Wang, Fang; Zhang, Jing; Zhao, Xing; Rui, Yichao; Wang, Yanfen; Hao, Yanbin; Cui, Xiaoyong] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Che, Rongxiao; Wang, Fang; Wang, Weijin; Xu, Zhihong] Griffith Univ, Environm Futures Res Inst, Sch Nat Sci, Brisbane, Qld 4111, Australia. [Wang, Weijin] Dept Sci Informat Technol & Innovat DSITI, Brisbane, Qld 4068, Australia. [Rui, Yichao] Univ Western Australia, UWA Sch Agr & Environm, Soil Biol & Mol Ecol Grp, Crawley 6009, Australia. RP Cui, XY (通讯作者)，Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. EM cuixy@ucas.ac.cn TC 34 Z9 36 PD DEC PY 2017 VL 136 IS 3 BP 341 EP 352 DI 10.1007/s10533-017-0399-5 UT WOS:000416325100008 DA 2023-03-23 ER PT J AU Chen, XP Wang, GX Zhang, T Mao, TX Wei, D Song, CL Hu, ZY Huang, KW AF Chen, Xiaopeng Wang, Genxu Zhang, Tao Mao, Tianxu Wei, Da Song, Chunlin Hu, Zhaoyong Huang, Kewei TI Effects of warming and nitrogen fertilization on GHG flux in an alpine swamp meadow of a permafrost region SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Uncertainties in the seasonal changes of greenhouse gases (GHG) fluxes in wetlands limit our accurate understanding of the responses of permafrost ecosystems to future warming and increased nitrogen (N) deposition. Therefore, in an alpine swamp meadow in the hinterland of the Qinghai-Tibet Plateau, a simulated warming with N fertilization experiment was conducted to investigate the key GHG fluxes (ecosystem respiration [Re], CH4 and N2O) in the early (EG), mid (MG) and late (LG) growing seasons. Results showed that warming (6.2 degrees C) increased the average seasonal Re by 30.9% and transformed the alpine swamp meadow from a N2O sink to a source, whereas CH4 flux was not significantly affected. N fertilization (4 g N m(-2) a(-1)) alone had no significant effect on the fluxes of GHGs. The interaction of warming and N fertilization increased CH4 uptake by 69.6% and N2O emissions by 26.2% compared with warming, whereas the Re was not significantly affected. During the EG, although the soil temperature sensitivity of the Re was the highest, the effect of warming on the Re was the weakest. The primary driving factor for Re was soil surface temperature, whereas soil moisture controlled CH4 flux, and the N2O flux was primarily affected by rain events. The results indicated: (i) increasing N deposition has both positive and negative feedbacks on GHG fluxes in response to climate warming; (ii) during soil thawing process at active layer, low temperature of deep frozen soils have a negative contribution to Re in alpine ecosystems; and (iii) although these alpine wetland ecosystems are buffers against increased temperature, their feedbacks on climate change cannot be ignored because of the large soil organic carbon pool and high temperature sensitivity of the Re. (C) 2017 Elsevier B.V. All rights reserved. C1 [Chen, Xiaopeng; Wang, Genxu; Wei, Da; Song, Chunlin; Hu, Zhaoyong; Huang, Kewei] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China. [Chen, Xiaopeng; Song, Chunlin; Hu, Zhaoyong; Huang, Kewei] Univ Chinese Acad Sci, Beijing 100039, Peoples R China. [Zhang, Tao] Guizhou Univ, Inst New Rural Dev, Guiyang 550025, Guizhou, Peoples R China. [Mao, Tianxu] Guizhou Univ, Coll Forestry, Guiyang 550025, Guizhou, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, 9 Fourth Sect,Renmin Rd South, Chengdu 610041, Sichuan, Peoples R China. EM wanggx@imde.ac.cn TC 40 Z9 46 PD DEC 1 PY 2017 VL 601 BP 1389 EP 1399 DI 10.1016/j.scitotenv.2017.06.028 UT WOS:000406294900136 DA 2023-03-23 ER PT J AU Lin, B Zhao, XR Zheng, Y Qi, S Liu, XZ AF Lin, Bin Zhao, Xiaorong Zheng, Yong Qi, Sha Liu, Xingzhong TI Effect of grazing intensity on protozoan community, microbial biomass, and enzyme activity in an alpine meadow on the Tibetan Plateau SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB The alpine meadow has received mounting attention due to its degradation resulting from overgrazing on the Tibetan Plateau. However, belowground biotic characteristics under varied grazing stresses in this ecosystem are poorly understood. Here, the responses of soil protozoan abundance, community composition, microbial biomass, and enzyme activity to five grazing patterns including (1) artificial grassland without grazing (AG), (2) winter grazing (WG), (3) grazing for 7 months within a fence (GF), (4) continuous grazing for a whole year (CG), and (5) natural heavy grazing (HG) were investigated for two continuous years. Soil protozoan community composition was investigated using the most possible number (MPN) method, and soil microbial biomass and enzyme activity were analyzed using chloroform fumigation extraction and substrate utilization methods, respectively. Multivariate statistical analysis, the analysis of variance (ANOVA), multiple comparisons, and correlation analysis were together performed. The WG treatment had the highest abundance of total protozoa (2342-2524 cell g(-1)). Compared with AG treatment, HG treatment significantly reduced the abundance of soil total, flagellate and ciliate protozoa, and protease activities in 2012 and 2013. Significantly, lower soil microbial biomass nitrogen (MBN) was also observed in the HG (6.60 and 14.6 mg N kg(-1)) than those in other four treatments (22.3-82.9 mg N kg(-1)) both in 2012 and 2013, whereas significantly higher microbial biomass carbon (MBC) was observed in HG than that in AG treatment in 2012. Moreover, significantly positive correlations were detected between the abundance of soil protozoa and soil moisture, pH, organic C, total N, and MBN. Our results indicated that soil protozoa showed a negative response to increasing grazing intensities and therefore, suggesting that aboveground grazing practices also exerted strong impact on belowground protozoa, not only on soil microbial characteristics. Soil protozoan community composition was apparently different between the HG treatment and other four grazing patterns and was potentially impacted by altered soil properties and MBC and/or MBN. Our results suggested that moderate grazing may sustain better belowground biotic diversity and ecosystem functioning in this alpine meadow on the Tibetan Plateau. C1 [Lin, Bin; Zheng, Yong; Qi, Sha; Liu, Xingzhong] Chinese Acad Sci, Inst Microbiol, State Key Lab Mycol, 3 Pk 1,Beichen West Rd, Beijing 100101, Peoples R China. [Lin, Bin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhao, Xiaorong] China Agr Univ, Coll Resource & Environm, 2 Yuanmingyuan West Rd, Beijing 100193, Peoples R China. RP Qi, S; Liu, XZ (通讯作者)，Chinese Acad Sci, Inst Microbiol, State Key Lab Mycol, 3 Pk 1,Beichen West Rd, Beijing 100101, Peoples R China. EM qis@im.ac.cn; liuxz@im.ac.cn TC 15 Z9 18 PD DEC PY 2017 VL 17 IS 12 BP 2752 EP 2762 DI 10.1007/s11368-017-1695-3 UT WOS:000415656300005 DA 2023-03-23 ER PT J AU Xie, QY Wang, XD Gao, YH Zhang, MY AF Xie, Qingyan Wang, Xiaodan Gao, Yongheng Zhang, Mengyao TI Short term effect of precipitation amount change on greenhouse gas emissions from alpine grassland in the eastern Qinghai-Tibetan Plateau SO RANGE MANAGEMENT AND AGROFORESTRY DT Article AB The effects of a change in the precipitation amount on greenhouse gases (GHGs) emission from the alpine grassland ecosystem have not yet to be elucidated. In this research, the GHGs (CO2, CH4 and N2O) fluxes in the eastern Qinghai-Tibetan Plateau were measured with an artificially increased precipitation (increase of 200 mm) and a decreased precipitation (decrease of 200 mm) by using the static chamber meteorological chromatography method in a growing season (from May to September). Under both increased precipitation (IP) and decreased precipitation (DP) experimental treatments, the alpine grassland functioned as the source of CO2 and N2O and as the CH4 sink. Compared to the control check (CK), the IP slightly enhanced the average CO2 and N2O emission fluxes by 4.2% (P>0.05) and 17.2% (P>0.05), respectively, but it declined the average CH4 absorption flux by 21.9% (P<0.05). In contrast, the DP decreased the average CO2 emission fluxes by 10.2% (P<0.05), slightly enhanced the average N2O emission fluxes by 4.6% (P>0.05), and increased the average CH4 absorption flux by 15.9% (P<0.05). C1 [Xie, Qingyan; Wang, Xiaodan; Gao, Yongheng; Zhang, Mengyao] Chinese Acad Sci, Inst Mt Hazards & Environm, Beijing, Peoples R China. [Xie, Qingyan] Beijing Normal Univ, Coll Global Change & Earth Syst Sci, Beijing, Peoples R China. RP Gao, YH (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Beijing, Peoples R China. EM yhgao@imde.ac.cn TC 1 Z9 1 PD DEC PY 2017 VL 38 IS 2 BP 151 EP 157 UT WOS:000426406800001 DA 2023-03-23 ER PT J AU Zheng, ZT Zhu, WQ AF Zheng, Zhoutao Zhu, Wenquan TI Uncertainty of Remote Sensing Data in Monitoring Vegetation Phenology: A Comparison of MODIS C5 and C6 Vegetation Index Products on the Tibetan Plateau SO REMOTE SENSING DT Article AB Vegetation phenology is considered a sensitive indicator of climate change, which controls carbon, nitrogen, and water cycles within terrestrial ecosystems. The Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) is an important moderate resolution remote sensing data for monitoring vegetation phenology. However, Terra MODIS Collection 5 (C5) vegetation index products were identified to be affected by sensor degradation, which has been addressed in the recently released MODIS Collection 6 (C6) vegetation index products. In order to compare the difference between MODIS C5 and C6 NDVI in monitoring vegetation phenology, the start and end of growing season (SOS and EOS) of the alpine grassland on the Tibetan Plateau (TP) were extracted using four common methods. Then, the C5 and C6 NDVI-derived SOS (SOSC5 and SOSC6) and EOS (EOSC5 and EOSC6) were compared with ground-observed phenology data. Results showed that the multi-year average growing season NDVIs of C6 were lower than those of C5 in most areas, while the inter-annual variation patterns of regional average SOSC5 and SOSC6 (EOSC5 and EOSC6) were consistent. However, large spatial differences in phenological trends were found between C5 and C6 NDVI products. From C5 to C6, pixels with a SOS (EOS) trend shifting from significant to insignificant or from insignificant to significant accounted for at least 14.58% (9.07%) of the total pixels. SOSC5 was more consistent than SOSC6 with the ground-observed green-up dates. C5 NDVI may be more appropriate for monitoring SOS than C6 NDVI in the study region, but more ground-observed phenology records are needed to confirm it due to only four observational sites in this study. However, large differences and poor correlations existed between EOSC5 (EOSC6) and the ground-observed beginning of leaf coloring. To further evaluate the uncertainty of MODIS C5 and C6 NDVI in monitoring vegetation phenology, higher resolution near-surface remote sensing data and corresponding validation methods should be applied. C1 [Zheng, Zhoutao; Zhu, Wenquan] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Zheng, Zhoutao; Zhu, Wenquan] JCGCS, Beijing 100875, Peoples R China. [Zheng, Zhoutao; Zhu, Wenquan] Beijing Normal Univ, Inst Remote Sensing Sci & Engn, Fac Geog Sci, Beijing Engn Res Ctr Global Land Remote Sensing P, Beijing 100875, Peoples R China. RP Zheng, ZT; Zhu, WQ (通讯作者)，Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China.; Zheng, ZT; Zhu, WQ (通讯作者)，JCGCS, Beijing 100875, Peoples R China.; Zheng, ZT; Zhu, WQ (通讯作者)，Beijing Normal Univ, Inst Remote Sensing Sci & Engn, Fac Geog Sci, Beijing Engn Res Ctr Global Land Remote Sensing P, Beijing 100875, Peoples R China. EM zhengzt90@mail.bnu.edu.cn; zhuwq75@bnu.edu.cn TC 23 Z9 25 PD DEC PY 2017 VL 9 IS 12 AR 1288 DI 10.3390/rs9121288 UT WOS:000419235700084 DA 2023-03-23 ER PT J AU Fu, G Shen, ZX AF Fu, Gang Shen, Zhen Xi TI Clipping has stronger effects on plant production than does warming in three alpine meadow sites on the Northern Tibetan Plateau SO SCIENTIFIC REPORTS DT Article AB The relative effects of warming and clipping on vegetation growth are not fully understood. Therefore, we compared the relative effects of experimental warming and clipping on the normalised difference vegetation index (NDVI), green NDVI (GNDVI), soil-adjusted vegetation index (SAVI), aboveground biomass (AGB) and gross primary production (GPP) in three alpine meadow sites (A, B and C) on the Northern Tibetan Plateau from 2013 to 2015. There were no obvious effects of experimental warming on the NDVI, GNDVI, SAVI, AGB and GPP at the three sites, which were most likely attributed to experimental warming-induced warming and drying conditions. In contrast, clipping significantly decreased the NDVI, SAVI and AGB by 27.8%, 31.3% and 18.2% at site A, by 27.1%, 31.8% and 27.7% at site B, and by 12.3%, 15.1% and 17.6% at site C, respectively. Clipping also significantly reduced the GNDVI and GPP by 11.1% and 28.2% at site A and by 18.9% and 33.7% at site B, respectively. Clipping marginally decreased the GNDVI by 8.7% (p = 0.060) and GPP (p = 0.082) by 14.4% at site C. Therefore, clipping had stronger effects on vegetation growth than did warming in the three alpine meadow sites on the Tibetan Plateau. C1 [Fu, Gang; Shen, Zhen Xi] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. RP Fu, G (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. EM fugang@igsnrr.ac.cn TC 7 Z9 7 PD NOV 27 PY 2017 VL 7 AR 16330 DI 10.1038/s41598-017-16645-2 UT WOS:000416307000005 DA 2023-03-23 ER PT J AU Zhang, ZH Zhu, XX Wang, SP Duan, JC Chang, XF Luo, CY He, JS Wilkes, A AF Zhang, Zhenhua Zhu, Xiaoxue Wang, Shiping Duan, Jichuang Chang, Xiaofeng Luo, Caiyun He, Jin-Sheng Wilkes, Andreas TI Nitrous oxide emissions from different land uses affected by managements on the Qinghai-Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB We evaluated the N2O emissions from four land use types (a native alpine meadow with winter grazing (NAM), an abandoned pasture (APL), a perennial Elymus nutans Griseb. pasture (PEN) and an annual Avena saliva L. pasture (AAS)) with and without three management practices (nitrogen (N) fertilizer, sheep manure and no tillage (NT)) in a Gelic Cambisol soil underlying an alpine meadow on the Qinghai-Tibetan Plateau in 2009 and 2010. Our results show that, compared with NAM, APL had significantly higher cumulative-average seasonal N2O emissions. Converting unmanaged APL to PEN or AAS significantly increased cumulative-average seasonal N2O emissions by 35% and 75%, respectively. Sheep manure and N fertilizer application significantly increased N2O emissions due to increased soil inorganic N concentration. The effect of sheep manure addition on N2O emissions was lower than that of N fertilizer. For AAS, tillage significantly decreased the effect of sheep manure application on N2O emissions. Compared with tillage, NT significantly decreased N2O emissions from AAS. Therefore, our results suggest that cultivating natural grassland would increase N2O emissions, and fertilizer application would amplify the magnitude of emissions, whereas NT could mitigate the fertilizer impact on N2O emission. Furthermore, the structural equation analysis revealed that land use change affected N2O emissions directly by influencing the number of plant species and soil characteristics. There were two different underlying mechanisms regulating N2O emissions in response to N fertilizer and sheep manure addition. C1 [Zhang, Zhenhua; Zhu, Xiaoxue; Luo, Caiyun; He, Jin-Sheng] Chinese Acad Sci, Northwest Inst Plateau Biol, Haibei Alpine Grassland Ecosyst Res Stn, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Qinghai, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. [Wang, Shiping] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhu, Xiaoxue] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Duan, Jichuang] Binhai Res Inst Tianjin, Tianjin 300457, Peoples R China. [Chang, Xiaofeng] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China. [He, Jin-Sheng] Peking Univ, Dept Ecol, Yi Fu Bldg 2,5 Yiheyuan Rd, Beijing 100871, Peoples R China. [Wilkes, Andreas] Dev Ltd, Bury St Edmunds IP33 3EQ, Suffolk, England. RP Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. EM wangsp@itpcas.ac.cn TC 6 Z9 6 PD NOV 15 PY 2017 VL 246 BP 133 EP 141 DI 10.1016/j.agrformet.2017.06.013 UT WOS:000408782000013 DA 2023-03-23 ER PT J AU Li, GY Jiang, GH Bai, J Jiang, CH AF Li, Guangyong Jiang, Guanghui Bai, Ju Jiang, Cuihong TI Spatio-temporal variation of alpine grassland spring phenological and its response to environment factors northeastern of Qinghai-Tibetan Plateau during 2000-2016 SO ARABIAN JOURNAL OF GEOSCIENCES DT Article AB Vulnerable alpine grassland ecosystem is highly sensitive to climate change, and its response and feedback to climate change have been intensely studied by the scientific community. In this study, the alpine grassland ecosystem in the Qinghai Lake watershed of the northeastern Qinghai-Tibet Plateau was selected as the research subject, and MODIS time series data and field sampling data were used to analyze the characteristics of the beginning of the growing season (BGS) pattern and the spatio-temporal variation and responded to environmental factors. The results show that under the combined influence of elevation, land surface temperature (LST), and soil moisture, the multi-year alpine grassland BGS pattern presents zonal horizontal characteristics with increasing delays from the southeast to the northwest and also exhibits non-zonal vertical characteristics in the western mountainous area. Alpine grassland BGS shows significant negative correlations with elevation and the 0-10 cm soil moisture content but a significant positive correlation with the mean spring LST. The relationships among BGS, elevation, and LST change when the elevation is over 4200 m, but the relationship between BGS and soil moisture continues to be a significant negative correlation. In the period 2000-2016, the BGS of the alpine grassland in the watershed generally advanced at the rate of 1.4 days/10 years and in local areas showed spatially heterogeneous trends. Spring soil moisture plays a key role in controlling spatio-temporal variations of BGS in the arid and semi-arid areas of the alpine zone relative to LST. Grassland degradation also affects the BGS spatio-temporal pattern and shows grassland degradation result of BGS in advance. The findings would provide a scientific reference for further understanding the mechanism of alpine vegetation phenology. C1 [Li, Guangyong; Jiang, Guanghui] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Fac Geog Sci, Beijing 100875, Peoples R China. [Li, Guangyong; Bai, Ju] Natl Geomat Ctr China, Beijing 100830, Peoples R China. [Jiang, Cuihong] Beijing Acad Agr & Forestry Sci, Inst Agr Sci Tech Informat, Beijing 100097, Peoples R China. RP Jiang, GH (通讯作者)，Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Fac Geog Sci, Beijing 100875, Peoples R China. EM macrophage@bnu.edu.cn TC 4 Z9 5 PD NOV 14 PY 2017 VL 10 IS 22 AR 480 DI 10.1007/s12517-017-3269-5 UT WOS:000415964200001 DA 2023-03-23 ER PT J AU Fang, K Kou, D Wang, GQ Chen, LY Ding, JZ Li, F Yang, GB Qin, SQ Liu, L Zhang, QW Yang, YH AF Fang, Kai Kou, Dan Wang, Guanqin Chen, Leiyi Ding, Jinzhi Li, Fei Yang, Guibiao Qin, Shuqi Liu, Li Zhang, Qiwen Yang, Yuanhe TI Decreased Soil Cation Exchange Capacity Across Northern China's Grasslands Over the Last Three Decades SO JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES DT Article AB Cation exchange capacity (CEC) helps soils hold nutrients and buffer pH, making it vital for maintaining basic function of terrestrial ecosystems. However, little is known about the temporal dynamics of CEC over broad geographical scales. In this study, we used random forest method to compare historical CEC data from the 1980s with new data from the 2010s across northern China's grasslands. We found that topsoil CEC in the 2010s was significantly lower than in the 1980s, with an overall decline of about 14%. Topsoil CEC decreased significantly in alpine meadow, alpine steppe, meadow steppe, and typical steppe by 11%, 20%, 27%, and 9%, respectively. Desert steppe was the only ecosystem type that experienced no significant change. CEC was positively related to soil carbon content, silt content, and mean annual precipitation, suggesting that the decline was potentially associated with soil organic carbon loss, soil degradation, soil acidification, and extreme precipitation across northern China's grasslands since the 1980s. Overall, our results demonstrate topsoil CEC loss due to environmental changes, which may alter the vegetation community composition and its productivity and thus trigger grassland dynamics under a changing environment. C1 [Fang, Kai; Kou, Dan; Wang, Guanqin; Chen, Leiyi; Ding, Jinzhi; Li, Fei; Yang, Guibiao; Qin, Shuqi; Liu, Li; Zhang, Qiwen; Yang, Yuanhe] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China. [Fang, Kai; Kou, Dan; Wang, Guanqin; Ding, Jinzhi; Li, Fei; Yang, Guibiao; Qin, Shuqi; Liu, Li; Zhang, Qiwen; Yang, Yuanhe] Univ Chinese Acad Sci, Beijing, Peoples R China. RP Yang, YH (通讯作者)，Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing, Peoples R China.; Yang, YH (通讯作者)，Univ Chinese Acad Sci, Beijing, Peoples R China. EM yhyang@ibcas.ac.cn TC 17 Z9 24 PD NOV PY 2017 VL 122 IS 11 BP 3088 EP 3097 DI 10.1002/2017JG003968 UT WOS:000418086800025 DA 2023-03-23 ER PT J AU Li, L Fassnacht, FE Storch, I Burgi, M AF Li, Li Fassnacht, Fabian E. Storch, Ilse Burgi, Matthias TI Land-use regime shift triggered the recent degradation of alpine pastures in Nyanpo Yutse of the eastern Qinghai-Tibetan Plateau SO LANDSCAPE ECOLOGY DT Article AB The eastern Qinghai-Tibetan Plateau is a cultural landscape where traditional pastoralism substantially shaped the present mosaic structure of the alpine grasslands. During the past two decades, however, severe grassland degradations of this region has been considered as the major ecological concern. In this study we took an interdisciplinary approach to investigate the impact of the historical land-use regimes to the observed degradation, by conducting an in-depth case study in a local pastoral village in the Nyanpo Yutse region. Firstly, we mapped historical land-use intensities (LUIs) of the study area at land-use transition time points of 1970s, 1984, 1994 and 2015 with oral history and participatory GIS (PGIS) approaches. Secondly, we conducted Landsat and Moderate Resolution Imaging Spectroradiometer (MODIS) time series analysis to detect the temporal and spatial patterns of the degradation. Thirdly, we discussed the causal relations between the land-use and land-cover changes. Livestock and pasture privatization from 1984 to 1994 created the land-use regime shift which resulted in a marked increase in LUIs and decreased pastoral mobility. The LUI increase in this transition period fostered the establishment of short-grass vegetation which facilitated the spreading of plateau pikas. The installment of iron fences as private pasture borders from 2004 to 2007 eventually started the onset of degradation. Our case study illustrates that the past land-use regime shift triggered the recent ecological regime shift in Nyanpo Yutse. Severe grassland degradation occurred with a time lag during which cumulative LUIs surpassed the vulnerability threshold of the biophysical system. C1 [Li, Li; Storch, Ilse] Univ Freiburg, Chair Wildlife Ecol & Management, Tennenbacher Str 4, D-79106 Freiburg, Germany. [Fassnacht, Fabian E.] Karlsruhe Inst Technol, Inst Geog & Geoecol, Kaiserstr 12, D-76131 Karlsruhe, Germany. [Burgi, Matthias] Swiss Fed Res Inst WSL, Res Unit Landscape Dynam, Zurcherstr 111, CH-8903 Birmensdorf, Switzerland. RP Li, L (通讯作者)，Univ Freiburg, Chair Wildlife Ecol & Management, Tennenbacher Str 4, D-79106 Freiburg, Germany. EM li.li@wildlife.uni-freiburg.de TC 41 Z9 44 PD NOV PY 2017 VL 32 IS 11 SI SI BP 2187 EP 2203 DI 10.1007/s10980-017-0510-2 UT WOS:000414975000008 DA 2023-03-23 ER PT J AU Pan, T Zou, XT Liu, YJ Wu, SH He, GM AF Pan, Tao Zou, Xintong Liu, Yujie Wu, Shaohong He, Guangming TI Contributions of climatic and non-climatic drivers to grassland variations on the Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB Grasslands cover a large portion of the global land surface, providing crucial ecosystem services for humans. During the past decades, grasslands of the Tibetan Plateau (TP), which is the highest plateau over the world, have experienced dramatic changes, especially degradation caused by intensifying climatic (e.g., warming, drying) and non-climatic (e.g., land use changes) drivers. However, it remains unclear how quantitatively different drivers contribute to grassland changes, which is critical for various stakeholders to make informative decisions to mitigate these changes. Here, we proposed a two-step methodology to tackle this challenge. First, the effects of land use changes on grassland distribution were investigated. Then the contributions of climatic and non-climatic drivers were discriminated through the differences between observed Normalized Difference Vegetation Index (NDVI) and simulated NDVI based on General Linear Models (GLM). Results show that the area of grasslands decreased from 1980 to 2010 due to land use changes. The area converted from grasslands to other land covers was larger than that converted from other land covers to grasslands. Grassland NDVI without land use changes did not increase significantly. Climatic drivers such as warming and wetting were beneficial to grassland quality, but continuous drying probably induced grassland degradation. Non-climatic drivers such as ecological programs improved grassland quality, while overgrazing might result in grassland degradation. Our findings indicate the impacts of non-climatic drivers on grassland variations were more intense than that of the climatic drivers in the past three decades. The relative contribution rate of non-climatic drivers (66.07%) doubled that of climatic drivers (33.93%) to grassland variations. The impacts of climatic drivers were relatively slow but persistent. Non-climatic drivers like ecological programs could effectively mitigate grassland degradation induced by land use changes or continuous drying on the TP. This study could provide scientific support for grassland restoration and management on the TP. C1 [Pan, Tao; Zou, Xintong; Liu, Yujie; Wu, Shaohong] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Zou, Xintong] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [He, Guangming] Michigan State Univ, MSU Innovat Ctr, E Lansing, MI 48823 USA. RP Liu, YJ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM liuyujie@igsnrr.ac.cn TC 72 Z9 78 PD NOV PY 2017 VL 108 BP 307 EP 317 DI 10.1016/j.ecoleng.2017.07.039 PN A UT WOS:000412127500035 DA 2023-03-23 ER PT J AU Xue, X You, QG Peng, F Dong, SY Duan, HC AF Xue, Xian You, Quangang Peng, Fei Dong, Siyang Duan, Hanchen TI Experimental Warming Aggravates Degradation-Induced Topsoil Drought in Alpine Meadows of the Qinghai-Tibetan Plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Climatic warming is presumed to cause topsoil drought by increasing evapotranspiration and water infiltration, and by progressively inducing land degradation in alpine meadows of the Qinghai-Tibetan Plateau. However, how soil moisture and temperature patterns of degraded alpine meadows respond to climate warming remains unclear. A 6-year continuous warming experiment was carried out in both degraded and undegraded alpine meadows in the source region of the Yangtze River. The goal was to identify the effects of climatic warming and land degradation on soil moisture (), soil surface temperature (T-sfc), and soil temperature (T-s). In the present study, land degradation significantly reduced by 45-61% at a depth of 0-100cm (p<0001) and increased the annual mean T-sfc by 08 degrees C. Warming with an infrared heater (radiation output of 150Wm(-2)) significantly increased the annual mean T-sfc by 25 degrees C (p<0001) and significantly increased by 47% at a depth of 40-60cm. Experimental warming in degraded land reversed the positive effects of the infrared heater and caused the yearly average to decrease significantly by 37-81% at a depth of 0-100cm. Our research reveals that land degradation caused a significant water deficit near the soil surface. Experimental warming aggravated topsoil drought caused by land degradation, intensified the magnitude of degradation, and caused a positive feedback in the degraded alpine meadow ecosystem. Therefore, an immediate need exists to restore degraded alpine meadow grasslands in the Qinghai-Tibetan Plateau in anticipation of a warmer future. Copyright (c) 2017 John Wiley & Sons, Ltd. C1 [Xue, Xian; You, Quangang; Peng, Fei; Dong, Siyang; Duan, Hanchen] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resource, Key Lab Desert & Desertificat, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. RP Xue, X (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resource, Key Lab Desert & Desertificat, 320 West Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. EM xianxue@lzb.ac.cn TC 23 Z9 27 PD NOV PY 2017 VL 28 IS 8 BP 2343 EP 2353 DI 10.1002/ldr.2763 UT WOS:000414626400002 DA 2023-03-23 ER PT J AU Chen, XP Wang, GX Huang, KW Hu, ZY Song, CL Liang, YM Wang, J Song, XY Lin, S AF Chen, Xiaopeng Wang, Genxu Huang, Kewei Hu, Zhaoyong Song, Chunlin Liang, Yiming Wang, Jian Song, Xiaoyan Lin, Shan TI The effect of nitrogen deposition rather than warming on carbon flux in alpine meadows depends on precipitation variations SO ECOLOGICAL ENGINEERING DT Article AB Uncertainties remain regarding the effects of climate warming and increasing nitrogen (N) deposition on greenhouse gas (GHG) flux in alpine grasslands due to a lack of knowledge about how hydrological characteristics control GHG fluxes. Therefore, a simulated warming and N fertilization experiment was conducted in a non-wetland (alpine meadow, AM) and a wetland (alpine swamp meadow, SM). We measured and analysed the key GHG fluxes (ecosystem respiration [Re], CH4 and N2O) of each treatment during two contrasting hydrological growing seasons. The results showed that: (i) warming increased the Re in both the AM and SM, warming increased the CH4 uptake in the AM but had no effect in the SM, and warming increased the N2O emissions from the AM and resulted in a change of the SM from a N2O sink into a source; (ii) N fertilization decreased the Re of the AM during the dry growing season and of the SM during the wet growing season, increased the CH4 uptake of the AM during the dry growing season, and had no effect on the CH4 and N2O fluxes of the SM; and (iii) the interaction between warming and N fertilization increased the CH4 uptake of the AM over the two growing seasons while increasing the CH4 uptake and N2O emissions of the SM during the dry growing season. Our results suggest that (i) the GHG flux of wetland ecosystems is more sensitive to precipitation variations than that of non-wetlands and (ii) precipitation controls the carbon (Re and CH4) flux response to increasing N deposition of these alpine meadows. (C) 2017 Elsevier B.V. All rights reserved. C1 [Chen, Xiaopeng; Wang, Genxu; Huang, Kewei; Hu, Zhaoyong; Song, Chunlin; Liang, Yiming; Wang, Jian; Song, Xiaoyan; Lin, Shan] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Sichuan, Peoples R China. [Chen, Xiaopeng; Huang, Kewei; Hu, Zhaoyong; Song, Chunlin; Liang, Yiming; Wang, Jian; Song, Xiaoyan; Lin, Shan] Univ Chinese Acad Sci, Beijing 100039, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, 9 Fourth Sect,Renmin Rd South, Chengdu 610041, Sichuan, Peoples R China. EM wanggx@imde.ac.cn TC 12 Z9 14 PD OCT PY 2017 VL 107 BP 183 EP 191 DI 10.1016/j.ecoleng.2017.07.018 UT WOS:000408676900019 DA 2023-03-23 ER PT J AU Sun, XH Zhao, Y Li, Q AF Sun, XiaoHong Zhao, Yan Li, Quan TI Holocene peatland development and vegetation changes in the Zoige Basin, eastern Tibetan Plateau SO SCIENCE CHINA-EARTH SCIENCES DT Article AB Peat sediments and peatland evolution process offer abundant clues into the history of vegetation and climate changes. In order to reconstruct Holocene peatland, vegetation and climate changes on eastern Tibetan Plateau, we conducted analyses of fossil pollen, loss-on-ignition, and carbon accumulation rate on one peat core from Zoige Basin. Our results show local peatland initiated at 10.3 ka, thrived in the early-mid Holocene, and then began to degrade. Throughout the Holocene, Zoige Basin was dominated by alpine meadow. Coniferous forest on montane regions expanded for several times during 10.5-4.6 ka, and then dramatically retreated. Results of peatland property, principal component analysis on fossil pollen suggested the climate maintained warm/wet during 10-5.5 ka, and became relatively cold/dry in the late Holocene. Rapid degradation of peatland, retreat of coniferous forest and climatic drought/cooling occurred at 10.2-10, 9.7-9.5, 8.7-8.5, 7.7-7.4, 6.4-6, 5.5-5.2, 4.8-4.5, 4-3.6, 3.1-2.7, 1.4-1.2 and 0.8-0.6 ka. The long-term variations of Holocene climate and vegetation on eastern Tibetan Plateau could be attributed to changes in insolation-driven temperature and Asian Summer Monsoon intensity, while those rapid centennial changes were probably triggered by abrupt monsoon failures and temperature anomalies in the high northern latitudes. C1 [Sun, XiaoHong; Zhao, Yan; Li, Quan] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Sun, XiaoHong; Zhao, Yan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Li, Q (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM liquan@igsnrr.ac.cn TC 23 Z9 27 PD OCT PY 2017 VL 60 IS 10 BP 1826 EP 1837 DI 10.1007/s11430-017-9086-5 UT WOS:000412466600008 DA 2023-03-23 ER PT J AU Wu, XW Cao, R Wei, X Xi, XQ Shi, PL Eisenhauer, N Sun, SC AF Wu, Xinwei Cao, Rui Wei, Xue Xi, Xinqiang Shi, Peili Eisenhauer, Nico Sun, Shucun TI Soil drainage facilitates earthworm invasion and subsequent carbon loss from peatland soil SO JOURNAL OF APPLIED ECOLOGY DT Article AB 1. Human activities have been a significant driver of environmental changes with tremendous consequences for carbon (C) dynamics. Peatlands are critical ecosystems because they store similar to 30% of the global soil organic C pool and are particularly vulnerable to anthropogenic changes. The Zoige peatland on the eastern Tibet Plateau, as the largest alpine peatland in the world, accounts for 1 parts per thousand of global peat soil organic C storage. However, this peatland has experienced dramatic climate change including increased temperature and reduced precipitation in the past decades, which likely is responsible for a decline of the water-table and facilitated earthworm invasion, two major factors reducing soil organic carbon (SOC) storage of peatlands. 2. Because earthworms often are more active in low-than in high-moisture peatlands, we hypothesized that the simultaneous occurrence of water-table decline and earthworm invasion would synergistically accelerate the release of SOC from peatland soil. We conducted a field experiment with a paired split-plot design, i.e. presence vs. absence of the invasive earthworms (Pheretima aspergillum) nested in drained vs. undrained plots, respectively, for 3 years within the homogenous Zoige peatland. 3. Water-table decline significantly decreased soil water content and bulk density, resulting in a marked reduction of SOC storage. Moreover, consistent with our hypothesis, earthworm presence dramatically reduced SOC in the drained but not in the undrained peatland through the formation of deep burrows and decreasing bulk density of the lower soil layer over 3 years. The variation in SOC likely was due to changes in above-ground plant biomass, root growth and earthworm behaviour induced by the experimental treatments. 4. Synthesis and applications. We suggest that incentive measures should be taken to prevent further water-table decline and earthworm invasion for maintaining the soil carbon pool in Zoige peatland. Artificial filling of drainage canals should be implemented to increase the water-table level, facilitating the recovery of drained peatlands. Moreover, the dispersal of earthworms and their cocoons attached to the roots of crop plants and tree saplings from low-lying areas to the Zoige region should be prevented. C1 [Wu, Xinwei; Cao, Rui; Xi, Xinqiang; Sun, Shucun] Nanjing Univ, Dept Ecol, Coll Life Sci, Nanjing 210023, Jiangsu, Peoples R China. [Wei, Xue; Sun, Shucun] Chengdu Inst Biol, Ctr Ecol Studies, 9 Sect 4 Renminnan Rd, Chengdu 610041, Sichuan, Peoples R China. [Shi, Peili] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Lhasa Natl Ecol Res Stn, Beijing 100101, Peoples R China. [Eisenhauer, Nico] German Ctr Integrat Biodivers Res iDiv, Deutsch Pl 5e, D-04103 Leipzig, Germany. [Eisenhauer, Nico] Univ Leipzig, Inst Biol, Johannisallee 21, D-04103 Leipzig, Germany. RP Sun, SC (通讯作者)，Nanjing Univ, Dept Ecol, Coll Life Sci, Nanjing 210023, Jiangsu, Peoples R China.; Sun, SC (通讯作者)，Chengdu Inst Biol, Ctr Ecol Studies, 9 Sect 4 Renminnan Rd, Chengdu 610041, Sichuan, Peoples R China. EM shcs@nju.edu.cn TC 18 Z9 19 PD OCT PY 2017 VL 54 IS 5 BP 1291 EP 1300 DI 10.1111/1365-2664.12894 UT WOS:000410678700002 DA 2023-03-23 ER PT J AU Mu, CC Abbott, BW Zhao, Q Su, H Wang, SF Wu, QB Zhang, TJ Wu, XD AF Mu, C. C. Abbott, B. W. Zhao, Q. Su, H. Wang, S. F. Wu, Q. B. Zhang, T. J. Wu, X. D. TI Permafrost collapse shifts alpine tundra to a carbon source but reduces N2O and CH4 release on the northern Qinghai-Tibetan Plateau SO GEOPHYSICAL RESEARCH LETTERS DT Article AB Important unknowns remain about how abrupt permafrost collapse (thermokarst) affects carbon balance and greenhouse gas flux, limiting our ability to predict the magnitude and timing of the permafrost carbon feedback. We measured monthly, growing-season fluxes of CO2, CH4, and N2O at a large thermokarst feature in alpine tundra on the northern Qinghai-Tibetan Plateau (QTP). Thermokarst formation disrupted plant growth and soil hydrology, shifting the ecosystem from a growing-season carbon sink to a weak source but decreasing feature level CH4 and N2O flux. Temperature-corrected ecosystem respiration from decomposing permafrost soil was 2.7 to 9.5-fold higher than in similar features from Arctic and Boreal regions, suggesting that warmer and dryer conditions on the northern QTP could accelerate carbon decomposition following permafrost collapse. N2O flux was similar to the highest values reported for Arctic ecosystems and was 60% higher from exposed mineral soil on the feature floor, confirming Arctic observations of coupled nitrification and denitrification in collapsed soils. Q(10) values for respiration were typically over 4, suggesting high-temperature sensitivity of thawed carbon. Taken together, these results suggest that QTP permafrost carbon in alpine tundra is highly vulnerable to mineralization following thaw, and that N2O production could be an important noncarbon permafrost climate feedback. Permafrost collapse altered soil hydrology, shifting the ecosystem from a carbon sink to carbon source but decreasing CH4 and N2O flux. Little to no vegetation recovery after stabilization suggests potentially large net carbon losses. High N2O flux compared to Arctic and Boreal systems suggests noncarbon permafrost climate feedback. C1 [Mu, C. C.; Zhao, Q.; Su, H.; Wang, S. F.; Zhang, T. J.] Lanzhou Univ, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Lanzhou, Gansu, Peoples R China. [Mu, C. C.; Wu, X. D.] Chinese Acad Sci, State Key Lab Cryosphere Sci, Northwest Inst Ecoenvironm & Resource, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou, Gansu, Peoples R China. [Abbott, B. W.] Michigan State Univ, Dept Earth & Environm Sci, E Lansing, MI 48824 USA. [Abbott, B. W.] Brigham Young Univ, Dept Plant & Wildlife Sci, Provo, UT 84602 USA. [Wu, Q. B.] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Northwest Inst Ecoenvironm & Resource, Lanzhou, Gansu, Peoples R China. RP Zhang, TJ (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Lanzhou, Gansu, Peoples R China.; Wu, XD (通讯作者)，Chinese Acad Sci, State Key Lab Cryosphere Sci, Northwest Inst Ecoenvironm & Resource, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou, Gansu, Peoples R China. EM tjzhang@lzu.edu.cn; wxd565@163.com TC 51 Z9 66 PD SEP 16 PY 2017 VL 44 IS 17 BP 8945 EP 8952 AR L074338 DI 10.1002/2017GL074338 UT WOS:000411702400032 DA 2023-03-23 ER PT J AU Cao, R Wei, X Yang, YHS Xi, XQ Wu, XW AF Cao, Rui Wei, Xue Yang, Yangheshan Xi, Xinqiang Wu, Xinwei TI The effect of water table decline on plant biomass and species composition in the Zoige peatland: A four-year in situ field experiment SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB The Zoige peatland is the largest alpine peatland in the world, and it is suffering the threat of water table decline. Plant productivity and species composition are important to ecosystem carbon sequestration and soil carbon input in peatlands. We examined the responses of plant community composition and biomass accumulation to water table decline to better understanding the responses of this peatland to environmental changes. A four-year in situ field experiment was conducted involving three treatments: deep, shallow, and control water tables, which were achieved by experimental drainage with 50 cm, 20 cm, and 0 cm deep ditches, respectively. Experimental drainage decreased the annual mean height of water table by ca. 12 cm and 15 cm (relative to the control) in the shallow and deep water table treatments, respectively, over the four years. The response of aboveground plant biomass (APB) to water table decline declined in the first year, remained unchanged in the second year and increased during the third and fourth years. However, water table decline had a non-significant effect on belowground plant biomass. This duration-dependent response of APB can be attributed to the changes in community species composition during the study years. Specifically, the negative effect of water table decline in the first year was due to the significant decrease in APB of hygrophytes (sedges and rushes). In the second year, although water table decline significantly increased APB of mesophytes (grasses and forbs), this increase was offset by the decrease in APB of hygrophytes, leading to a neutral effect. In both the third and fourth years, the extent of the increase in APB of mesophytes (typically the forb species Anemone trullifolia var. linearis) was greater than that of the decrease in APB of hygrophytes, leading to a positive effect. Our results indicate that short-term decline of the water table may increase the primary productivity by shifting dominant species of hygrophytes to mesophytes in the Zogie peatland. C1 [Cao, Rui; Yang, Yangheshan; Xi, Xinqiang; Wu, Xinwei] Nanjing Univ, Sch Life Sci, Dept Ecol, 163 Xianlin Ave, Nanjing 210023, Jiangsu, Peoples R China. [Wei, Xue] Chinese Acad Sci, Chengdu Inst Biol, ECORES Lab, Chengdu 610041, Peoples R China. RP Wu, XW (通讯作者)，Nanjing Univ, Sch Life Sci, Dept Ecol, 163 Xianlin Ave, Nanjing 210023, Jiangsu, Peoples R China. EM wuxw@nju.edu.cn TC 17 Z9 21 PD SEP 1 PY 2017 VL 247 BP 389 EP 395 DI 10.1016/j.agee.2017.07.008 UT WOS:000408597800043 DA 2023-03-23 ER PT J AU He, SY Richards, K AF He, Siyuan Richards, Keith TI Kobresia meadow degradation and its impact on water status SO ECOHYDROLOGY DT Article AB Alpine Kobresia meadows are valuable pasture resources on the central and eastern QinghaiTibetan Plateau that are also important in preserving local and regional water. Kobresia pygmaea is the dominant species forming a typical turf layer resistant to disturbance; however, overgrazing may have exceeded that resistance. An integrated approach, including field monitoring, soil sampling, stable isotope hydrology, and physical modelling, was used to evaluate the hydrological consequences of meadow degradation with respect to normal meadow, degraded crust, and bare soil. Multiple evidence confirms that the soil moisture condition worsens when the meadow degrades. Bare soil has the coarsest soil texture, rapid infiltration, and low soil moisture in the root zone, and soil evaporation rate is high compared to normal meadow especially in dry periods. Crusted meadow soil has the lowest surface infiltration and a larger exposure of the leaf surface because of low plant cover over a dark surface, which favours high transpiration. Crusted meadow also has a drier condition in the root zone. These suggest that degradation is a positive feedback process in which leaf and soil exposure to radiation strengthen water demand for transpiration and facilitate non-productive water loss, leaving the root zone (0-20 cm) dry and subject to further soil erosion. This positive process suggests that recovery of the Kobresia meadow is a long-term task which has to consider the different levels of degradation and the effects of local climate change, in order to adapt the rangeland management practices, to the needs of meadow conservation and restoration. C1 [He, Siyuan] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [He, Siyuan; Richards, Keith] Univ Cambridge, Dept Geog, Downing Pl, Cambridge CB2 3EN, England. RP He, SY (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM siyuan.he@bnu.edu.cn TC 5 Z9 5 PD SEP PY 2017 VL 10 IS 6 AR e1844 DI 10.1002/eco.1844 UT WOS:000410633100014 DA 2023-03-23 ER PT J AU Jiang, LB Zhang, L Deng, BL Liu, XS Yi, HQ Xiang, H Li, Z Zhang, WY Guo, XM Niu, DK AF Jiang, Liangbo Zhang, Ling Deng, Bangliang Liu, Xishuai Yi, Huiqin Xiang, Hai Li, Zhi Zhang, Wenyuan Guo, Xiaomin Niu, Dekui TI Alpine meadow restorations by non-dominant species increased soil nitrogen transformation rates but decreased their sensitivity to warming SO JOURNAL OF SOILS AND SEDIMENTS DT Article; Proceedings Paper CT 8th International Symposium on Forest Soils - Linking Soil Processes to Forest Productivity and Water Protection under Global Change CY OCT 24-28, 2015 CL Fujian Normal Univ, Fuzhou, PEOPLES R CHINA HO Fujian Normal Univ AB Alpine meadow soils are large carbon (C) and nitrogen (N) pools correlated significantly with global C and N cycling. Soil N transformations, including nitrification and N mineralization, are key processes controlling N availability. Alpine meadow degradations are common worldwide, and vegetation restorations have been widely implemented. However, grass species used for restorations may alter soil N transformations or their response to warming and N deposition due to divergent plant traits and their different effects on soil characteristic. To understand the effects of meadow restorations by non-historically dominant species on N transformations, we measured N transformation rates in restored soils and control soils under the context of warming and N deposition. We collected soils from plots restored by dominant (Miscanthus floridulus) and non-dominant species (including Carex chinensis and Fimbristylis dichotoma) and non-restored plots in alpine meadows of Wugong Mountain, China. We measured nitrification and N mineralization rates when soils were incubated at different temperature (15 or 25 A degrees C) and N additions (control vs. 4 g m(-2)) to examine their responses to restoration species, warming, and N. Vegetation restored soils differed substantially from non-restored bare soils. Total N, total organic C, pH, and dissolved organic C contributed the most to the separation. Restoration altered soil N transformations substantially, even though the effects varied among restoration species. Specifically, non-historically dominant species accelerated N transformations, while the originally dominant species decreased N transformations. In addition, sensitivity of nitrification to warming in restored soils was decreased by restorations. Soils restored by originally dominant species were higher in sensitivity of N transformations to warming than those restored by the other two species. Warming increased nitrification rates by 45.5 and 17.4 % in bare soils and restored soils, respectively. Meanwhile, N mineralization rates were increased by 52.8 and 21.9 %, respectively. Vegetation restoration of the degraded meadows impacted N transformations and their sensitivity to warming. The effects varied with identity of the restoration species, suggesting that grass species should be considered in future restorations of degraded meadows in terms of their divergent effects on N transformations and sensitivity to warming. C1 [Jiang, Liangbo; Zhang, Ling; Deng, Bangliang; Liu, Xishuai; Yi, Huiqin; Xiang, Hai; Li, Zhi; Zhang, Wenyuan; Guo, Xiaomin] Jiangxi Agr Univ, Coll Forestry, Coinnovat Ctr Jiangxi Typical Trees Cultivat & Ut, Jiangxi Key Lab Silviculture, Nanchang 330045, Jiangxi, Peoples R China. [Zhang, Wenyuan] Griffith Univ, Environm Futures Res Inst, Sch Nat Sci, Brisbane, Qld 4111, Australia. [Niu, Dekui] Jiangxi Agr Univ, Coll Land Resources & Environm, Nanchang 330045, Jiangxi, Peoples R China. RP Zhang, L (通讯作者)，Jiangxi Agr Univ, Coll Forestry, Coinnovat Ctr Jiangxi Typical Trees Cultivat & Ut, Jiangxi Key Lab Silviculture, Nanchang 330045, Jiangxi, Peoples R China. EM lingzhang09@126.com TC 16 Z9 17 PD SEP PY 2017 VL 17 IS 9 BP 2329 EP 2337 DI 10.1007/s11368-016-1488-0 UT WOS:000407481200012 DA 2023-03-23 ER PT J AU Zhang, CH Willis, CG Klein, JA Ma, Z Li, JY Zhou, HK Zhao, XQ AF Zhang, Chunhui Willis, Charles G. Klein, Julia A. Ma, Zhen Li, Junyong Zhou, Huakun Zhao, Xinquan TI Recovery of plant species diversity during long-term experimental warming of a species-rich alpine meadow community on the Qinghai-Tibet plateau SO BIOLOGICAL CONSERVATION DT Article AB Climate change is predicted to dramatically alter the composition of plant communities. The impact of climate change on these communities is often based on short-term warming experiments, which have revealed marked declines in species diversity in response to relatively minor increases in average annual temperatures. The long-term effects of such warming on community diversity and composition, however, are less well understood. Here, we formalize a hypothesis of rebounding diversity, where species richness initially declines in response to warming, but subsequently recovers through a combination of colonization (via dispersal and seed banks) and competitive release (via shifts in the dominant species). We compared long-term changes in species diversity and abundance between control and experimentally warmed (1-2 degrees C) plots, sampled over an 18-year period, in alpine meadow communities of the Qinghai-Tibet plateau. While there was an initial decline in species diversity by c. 40% (11-19 species) over the first four years, 18 years later, diversity had rebounded to initial levels, on a par with control plots. The composition of the experimentally warmed communities, however, was significantly altered. Our study suggests that short-term experiments may be insufficient to capture the temporal variability in community diversity and composition in response to climate change. Rather, the long-term impacts of continued global warming are predicted to result in highly dynamic processes of community reassembly and turnover that do not necessarily lead to a net decline in local diversity, but do lead to the formation of novel communities. C1 [Zhang, Chunhui] Qinghai Univ, State Key Lab Plateau Ecol & Agr, Xining 810016, Qinghai, Peoples R China. [Zhang, Chunhui; Ma, Zhen; Zhou, Huakun; Zhao, Xinquan] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Qinghai, Peoples R China. [Willis, Charles G.] Harvard Univ Herbaria, Cambridge, MA 02138 USA. [Klein, Julia A.] Colorado State Univ, Dept Ecosyst Sci & Sustainabil, Ft Collins, CO 80525 USA. [Klein, Julia A.] Colorado State Univ, Nat Resource Ecol Lab, Ft Collins, CO 80525 USA. [Ma, Zhen; Zhou, Huakun; Zhao, Xinquan] Key Lab Restorat Ecol Cold Reg Lab Qinghai, Xining 810008, Qinghai, Peoples R China. [Li, Junyong] Henan Univ, Coll Environm & Planning, Key Lab Geospatial Technol Middle & Lower Yellow, Kaifeng 475004, Henan, Peoples R China. RP Ma, Z; Zhou, HK; Zhao, XQ (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Qinghai, Peoples R China. EM mazhen@nwipb.cas.cn; hkzhou@nwipb.cas.cn; xqzhao@nwipb.cas.cn TC 36 Z9 39 PD SEP PY 2017 VL 213 BP 218 EP 224 DI 10.1016/j.biocon.2017.07.019 PN A UT WOS:000410014100025 DA 2023-03-23 ER PT J AU Zhao, GS Shi, PL AF Zhao, Guang-shuai Shi, Pei-li TI Sources of uncertainty in exploring rangeland phenology: A case study in an alpine meadow on the central Tibetan Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Global climate change has been found to substantially influence the phenology of rangeland, especially on the Tibetan Plateau. However, there is considerable controversy about the trends and causes of rangeland phenology owing to different phenological exploration methods and lack of ground validation. Little is known about the uncertainty in the exploration accuracy of vegetation phenology. Therefore, in this study, we selected a typical alpine rangeland near Damxung national meteorological station as a case study on central Tibetan Plateau, and identified several important sources influencing phenology to better understand their effects on phenological exploration. We found man-made land use was not easily distinguished from natural rangelands, and therefore this may confound phenological response to climate change in the rangeland. Change trends of phenology explored by four methods were similar, but ratio threshold method (RTM) was more suitable for exploring vegetation phenology in terms of the beginning of growing season (BGS) and end of growing season (EGS). However, some adjustments are needed when RTM is used in extreme drought years. MODIS NDVI/EVI dataset was most suitable for exploring vegetation phenology of BGS and EGS. The discrimination capacities of vegetation phenology declined with decreasing resolution of remote sensing images from MODIS to GIMMS AVHRR datasets. Additionally, distinct trends of phenological change rates were indicated in different terrain conditions, with advance of growing season in high altitudes but delay of season in lower altitudes. Therefore, it was necessary to eliminate interference of complex terrain and man-made land use to ensure the representativeness of natural vegetation. Moreover, selecting the appropriate method to explore rangelands and fully considering the impact of topography are important to accurately analyze the effects of climate change on vegetation phenology. C1 [Zhao, Guang-shuai; Shi, Pei-li] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Shi, Pei-li] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhao, Guang-shuai] China Natl Forestry Econ & Dev Res Ctr, Beijing 100714, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China.; Shi, PL (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM zhaogsh@126.com; shipl@igsnrr.ac.cn TC 2 Z9 2 PD SEP PY 2017 VL 14 IS 9 BP 1827 EP 1838 DI 10.1007/s11629-016-4115-z UT WOS:000409490000013 DA 2023-03-23 ER PT J AU Zhi, JJ Zhang, GL Yang, F Yang, RM Liu, F Song, XD Zhao, YG Li, DC AF Zhi, Junjun Zhang, Ganlin Yang, Fei Yang, Renmin Liu, Feng Song, Xiaodong Zhao, Yuguo Li, Decheng TI Predictingmattic epipedons in the northeastern Qinghai-Tibetan Plateau using Random Forest SO GEODERMA REGIONAL DT Article AB Mattic epipedon (ME), a special diagnostic surface horizon for soils in alpine meadow, plays an important role in carbon storage, soil water retention, and indication of alpine meadow degradation. At the global scale, it mainly distributes in the Qinghai-Tibetan Plateau and other similar alpine environments. However, its spatial patterns and the relations with environmental conditions remain unknown. This study attempts to explore key environmental variables responsible for the occurrence of the special surface soil horizon and based on those factors to predict and map digitally the spatial distribution of ME. By combining a variable selection procedure and the Random Forest (RF) algorithm, the variables extracted from Landsat 5 TM mosaic image, ASTER GDEM, and climate data were optimized and their importance was measured. The classification accuracy was compared with that obtained from binary logistic regression algorithm. In addition, a land use/land cover (LULC) map-based modification was conducted to further improve the classification accuracy. Results showed that the variable selection procedure had little effect in improving prediction accuracy. However, the number of used variables markedly reduced from 26 to 6 with a 77% decrease, which could speed up the training of the RF model (about one-third of the computation time could be saved). Analysis of variable importance showed that band 3 of TM and normalized difference vegetation index were the most important environmental variables influencing the occurrence of ME. The final overall accuracy of the ME map was predicted to be 84%. Our results demonstrate that the proposed procedure, which combined the proposed variables (derived from remote sensing, GDEM, and climate data), the variable selection approach, the RF algorithm, and the LULC map-based modification method can identify key environmental variables influencing the occurrence of ME and map the spatial distribution of ME effectively on the Qinghai-Tibetan Plateau. (c) 2017 Published by Elsevier B.V. C1 [Zhi, Junjun; Zhang, Ganlin; Yang, Fei; Yang, Renmin; Liu, Feng; Song, Xiaodong; Zhao, Yuguo; Li, Decheng] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, 71 East Beijing Rd, Nanjing 210008, Jiangsu, Peoples R China. [Zhang, Ganlin; Yang, Fei; Yang, Renmin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Zhang, GL (通讯作者)，Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, 71 East Beijing Rd, Nanjing 210008, Jiangsu, Peoples R China. EM glzhang@issas.ac.cn TC 24 Z9 26 PD SEP PY 2017 VL 10 BP 1 EP 10 DI 10.1016/j.geodrs.2017.02.001 UT WOS:000457279000002 DA 2023-03-23 ER PT J AU Zhao, ZZ Dong, SK Jiang, XM Liu, SL Ji, HZ Li, Y Han, YH Sha, W AF Zhao, Zhenzhen Dong, Shikui Jiang, Xiaoman Liu, Shiliang Ji, Hanzhong Li, Yu Han, Yuhui Sha, Wei TI Effects of warming and nitrogen deposition on CH4, CO2 and N2O emissions in alpine grassland ecosystems of the Qinghai-Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Increases in nitrogen (N) deposition along with climate warming can change the dynamics of carbon and nitrogen in the soil, and alter greenhouse gases (GHGs) fluxes. To examine how N deposition and warming affect GHGs (CH4, CO2 and N2O) fluxes in alpine grasslands, we conducted experiments in an alpinemeadow (AM), alpine-steppe (AS), and alpine cultivated grassland (CG) on the Qinghai-Tibetan Plateau (QTP). We simulated N deposition by treating soil with ammonium nitrate (NH4NO3) (8 kg N ha(-1) year(-1)), a warming treatment using an open top chamber (OTC) was carried out, and a combined treatment of warming and N deposition (8 kg N ha(-1) year(-1)) was conducted. The GHGs were collected during early, peak, and late plant growing seasons, i.e., May, August, and October of 2015, respectively, using a static chamber. We found, in general, neither N deposition nor warming solely altered CH4 and N2O fluxes in the alpine grasslands. The N deposition under warming conditions reduced CO2 emission significantly. The reduction of CO2 emission was most significant in the alpine steppe. The effects of climaticwarming and N deposition on the GHGs varied greatly across the grassland types and the growing seasons. The cultivated grasslands were much more unstable than the native grasslands in CH4 uptake. In can be concluded the N deposition associated with human activities may buffer the CO2 emission in the alpine grassland ecosystems in terms of climate changes on the QTP. (C) 2017 Elsevier B.V. All rights reserved. C1 [Zhao, Zhenzhen; Dong, Shikui; Jiang, Xiaoman; Liu, Shiliang; Li, Yu; Han, Yuhui; Sha, Wei] Beijing Normal Univ, Sch Environm, 19 XinJieKouWai St, Beijing 100875, Peoples R China. [Ji, Hanzhong] Anim Husb & Sci Res Inst Qinghai Prov, Haibei 810200, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, 19 XinJieKouWai St, Beijing 100875, Peoples R China. EM dsk03037@bnu.edu.cn TC 81 Z9 94 PD AUG 15 PY 2017 VL 592 BP 565 EP 572 DI 10.1016/j.scitotenv.2017.03.082 UT WOS:000400082100059 DA 2023-03-23 ER PT J AU Yang, SZ Liebner, S Winkel, M Alawi, M Horn, F Dorfer, C Ollivier, J He, JS Jin, HJ Kuhn, P Schloter, M Scholten, T Wagner, D AF Yang, Sizhong Liebner, Susanne Winkel, Matthias Alawi, Mashal Horn, Fabian Doerfer, Corina Ollivier, Julien He, Jin-Sheng Jin, Huijun Kuehn, Peter Schloter, Michael Scholten, Thomas Wagner, Dirk TI In-depth analysis of core methanogenic communities from high elevation permafrost-affected wetlands SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB The organic carbon of permafrost affected soils is receiving particular attention with respect to its fate and potential feedback to global warming. The structural and activity changes of methanogenic communities in the degrading permafrost-affected wetlands on the Tibetan Plateau can serve as fundamental elements for modelling feedback interaction of ecosystems to climate change. Hence, we aimed at anticipating if and how the rapid environmental changes occurring especially on the high altitude Tibetan platform will affect methanogenic communities. We identified methanogenic community composition, activity and abundance in wetland soils with different hydrological settings, permafrost extent and soil properties and pinpoint the environmental controls. We show that despite a pronounced natural gradient, the Tibetan high elevation wetland soils host a large methanogenic core microbiome. Hydrogenotrophic methanogens, in particular Methanoregula, and H2-dependent methanogenesis were overall dominant although acetoclastic methanogens in addition to hydrogenotrophs were among the dominating taxa in a minerotrophic fen. Tracing the Methanoregula community of the Tibetan Plateau using public databases revealed its global relevance in natural terrestrial habitats. Unlike the composition, the activity and abundance of methanogens varied strongly in the studied soils with higher values in alpine swamps than in alpine meadows. This study indicates that in the course of current wetland and permafrost degradation and the loss in soil moisture, a decrease in the methane production potential is expected on the high Tibetan Plateau but it will not lead to pronounced changes within the methanogenic community structure. (C) 2017 The Authors. Published by Elsevier Ltd. C1 [Yang, Sizhong; Liebner, Susanne; Winkel, Matthias; Alawi, Mashal; Horn, Fabian; Wagner, Dirk] GFZ German Res Ctr Geosci, Sect Geomicrobiol 5 3, D-14473 Potsdam, Germany. [Yang, Sizhong; Jin, Huijun] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soils Engn, Lanzhou 730000, Peoples R China. [Doerfer, Corina; Kuehn, Peter; Scholten, Thomas] Univ Tubingen, Dept Geosci, D-72074 Tubingen, Germany. [Ollivier, Julien; Schloter, Michael] Helmholtz Zentrum Munchen, Res Unit Comparat Microbiome Anal, D-85764 Neuherberg, Germany. [He, Jin-Sheng] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. RP Wagner, D (通讯作者)，GFZ German Res Ctr Geosci, Sect Geomicrobiol 5 3, D-14473 Potsdam, Germany. EM dirk.wagner@gfz-potsdam.de TC 32 Z9 33 PD AUG PY 2017 VL 111 BP 66 EP 77 DI 10.1016/j.soilbio.2017.03.007 UT WOS:000401877800008 DA 2023-03-23 ER PT J AU Cai, YJ Du, ZY Yan, Y Wang, XD Liu, XP AF Cai, Yanjiang Du, Ziyin Yan, Yan Wang, Xiaodan Liu, Xiuping TI Greater stimulation of greenhouse gas emissions by stored yak urine than urea in an alpine steppe soil from the Qinghai-Tibetan Plateau: A laboratory study SO GRASSLAND SCIENCE DT Article AB Urine deposition by grazing animals, with urea as the major constituent, is an important nitrogen (N) source in grassland ecosystems and may affect the production of three potent greenhouse gases (GHGs): nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2). However, owing to the greater chemical complexity of urine, the effect of urine on GHG emissions may differ from that of urea, and this difference has not been well reported. A short-term laboratory study was conducted to examine the influence of stored yak urine and urea at addition rates of 350 and 700 mg N m(-1) soil on GHG emissions at 20 and 60% water holding capacity (WHC) in an alpine steppe soil from the Qinghai-Tibetan Plateau. Compared with no N addition, urea led to greater increases in soil ammonium N (NH4+-N) concentrations, while yak urine resulted in a greater increase in soil dissolved organic carbon concentrations. Greater (P < 0.05) cumulative N2O and CH4 emissions occurred under 60% than 20% WHC, but soil moisture content did not affect CO2 emissions (P > 0.05). There were no statistically significant (P > 0.05) differences in N2O or CH4 emissions between the two N-addition rates, regardless of N type. The increases in N2O and CH4 emissions after N addition were greater in the urine than in the urea treatments, particularly under 60% WHC. The average CO2 emissions for the two soil moisture contents in the urine treatments increased with increasing N-addition rate, but the two urea treatments showed similar values to the control. The greater GHG emissions in the stored yak urine treatments were probably due to the existence of intrinsic organic carbon. Our results suggest that fresh yak urine may also possibly cause more GHG losses than urea under equivalent N application rates in alpine steppe soil on the Qinghai-Tibetan Plateau. C1 [Cai, Yanjiang; Du, Ziyin; Yan, Yan; Wang, Xiaodan] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu, Peoples R China. [Cai, Yanjiang] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing, Jiangsu, Peoples R China. [Liu, Xiuping] Chinese Acad Sci, Inst Genet & Dev Biol, Ctr Agr Resources Res, Shijiazhuang, Peoples R China. RP Cai, YJ (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, 9,Block 4,Renminnanlu Rd, Chengdu 610041, Peoples R China. EM yanjiangcai@163.com TC 5 Z9 11 PD JUL PY 2017 VL 63 IS 3 BP 196 EP 207 DI 10.1111/grs.12164 UT WOS:000404757800007 DA 2023-03-23 ER PT J AU Chen, JJ Yi, SH Qin, Y AF Chen, Jianjun Yi, Shuhua Qin, Yu TI The contribution of plateau pika disturbance and erosion on patchy alpine grassland soil on the Qinghai-Tibetan Plateau: Implications for grassland restoration SO GEODERMA DT Article AB Patchy alpine grassland with soil excavated by plateau pika (Ochotona curzoniae) and with bald patches is common on the Qinghai-Tibetan Plateau (QTP) where desertification has developed rapidly over the last few decades. This may have significant effects on alpine grassland restoration, by changing soil properties. In this study, the contribution of plateau pika disturbance and erosion on patchy alpine grassland soil, were examined by classifying the surface of the patchy grassland into 4 types vegetation patch, new pika pile, old pika pile and bald patch and comparing (t)he gravel content of the top layer of soil, soil moisture, soil hardness, soil organic carbon (SOC), and soil total nitrogen (TN) among them in the four study areas with different climatic conditions, altitudes, and grassland types on the QTP. We also analyzed the relationship between the amount of soil surface gravel and the Green Fractional Vegetation Cover (GFVC) using aerial photos. The results showed that (1) gravel content was significantly greater in bald patches and pika piles than in vegetation patches (p < 0.05); (2) soil moisture, hardness, SOC and TN were the highest in vegetation patches, and significantly lower in pika piles than in vegetation patches (p < 0.05); (3) GFVC was negatively and linearly correlated with the amount of soil surface gravel, with the amount of soil surface gravel in non-vegetation patches significantly greater than in vegetation patches (p < 0.001). Our results suggested that pika burrowing activity may increase the gravel content of the top layer of soil and decrease soil moisture, hardness, SOC and TN, which can increase soil erosion and hinder vegetation restoration. (C) 2017 Elsevier B.V. All rights reserved. C1 [Chen, Jianjun; Yi, Shuhua; Qin, Yu] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, 320 Donggang West Rd, Lanzhou 730000, Peoples R China. [Chen, Jianjun] Univ Chinese Acad Sci, 19 A Yuquan Rd, Beijing 100049, Peoples R China. [Yi, Shuhua] Nantong Univ, Sch Geog Sci, 999 Tongjing Rd, Nantong 226007, Peoples R China. RP Yi, SH (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Cryospher Sci, 320 Donggang West Rd, Lanzhou 730000, Peoples R China. EM yis@lzb.ac.cn TC 58 Z9 68 PD JUL 1 PY 2017 VL 297 BP 1 EP 9 DI 10.1016/j.geoderma.2017.03.001 UT WOS:000399627300001 DA 2023-03-23 ER PT J AU Wang, CT Wang, GX Wu, PF Rafique, R Zi, HB Li, XZ Luo, YQ AF Wang, Changting Wang, Genxu Wu, Pengfei Rafique, Rashid Zi, Hongbiao Li, Xiangzhen Luo, Yiqi TI EFFECTS OF ANT MOUNDS ON THE PLANT AND SOIL MICROBIAL COMMUNITY IN AN ALPINE MEADOW OF QINGHAI-TIBET PLATEAU SO LAND DEGRADATION & DEVELOPMENT DT Article AB Ants are important soil engineers, affecting the structure and function of ecosystems. To address the impacts of ants (Camponotus herculeanus) on the properties of an alpine meadow ecosystem of Qinghai-Tibet Plateau, we investigated the effects of ant mounds on plant biomass, soil physicochemical properties, microbial diversity, and functions. We found that the total biomass of plant community was significantly greater in ant mound periphery. Plant species richness in ant mounds was reduced compared with that of control plots without ant mounds. Significant changes in physicochemical properties of soil were also observed. Soil organic matter, total nitrogen, available phosphorous, total potassium, and available potassium increased in ant mound soil due to the excavation activities by ants as well as the accumulation of organic matter and other nutrients during mound construction. For example, roots/soil contents (g/g) and soil moisture in ant mound soils were lower than those in controls. Microbial community composition and microbial biomass were clearly changed in ant mound soils. BIOLOG analysis further indicated that the functional diversity of the microbial community of ant mound soil increased and differed from that of controls. This study indicates that ant-induced modification of soil properties indirectly influences plant biomass and species composition, and ant mounds have different microbial communities from those of control soil. Copyright (C) 2016 John Wiley & Sons, Ltd. C1 [Wang, Changting; Wu, Pengfei; Zi, Hongbiao] Southwest Univ Nationalities, Coll Life Sci & Technol, 16 South Sect 4,Yihuan Rd, Chengdu 610041, Sichuan, Peoples R China. [Wang, Genxu] Chinese Acad Sci, Inst Hazards & Environm, Chengdu 610041, Sichuan, Peoples R China. [Rafique, Rashid; Luo, Yiqi] Univ Oklahoma, Dept Microbiol & Plant Biol, Norman, OK 73019 USA. [Li, Xiangzhen] Chinese Acad Sci, Chengdu Inst Biol, Environm Microbiol Key Lab Sichuan Prov, Key Lab Environm & Appl Microbiol, 17 South Sect 2,Yihuan Rd, Chengdu 610041, Peoples R China. RP Wang, CT (通讯作者)，Southwest Univ Nationalities, Coll Life Sci & Technol, 16 South Sect 4,Yihuan Rd, Chengdu 610041, Sichuan, Peoples R China.; Li, XZ (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Environm Microbiol Key Lab Sichuan Prov, Key Lab Environm & Appl Microbiol, 17 South Sect 2,Yihuan Rd, Chengdu 610041, Peoples R China. EM wangct@swun.edu.cn; lixz@cib.ac.cn TC 10 Z9 13 PD JUL PY 2017 VL 28 IS 5 BP 1538 EP 1548 DI 10.1002/ldr.2681 UT WOS:000407990500005 DA 2023-03-23 ER PT J AU Wang, Y Heberling, G Gorzen, E Miehe, G Seeber, E Wesche, K AF Wang, Yun Heberling, Gwendolyn Goerzen, Eugen Miehe, Georg Seeber, Elke Wesche, Karsten TI Combined effects of livestock grazing and abiotic environment on vegetation and soils of grasslands across Tibet SO APPLIED VEGETATION SCIENCE DT Article AB QuestionsLivestock grazing and abiotic environmental factors both shape grassland systems; however, the relative importance of their impacts on plant species composition and soil fertility has rarely been investigated. Focusing on Tibetan grasslands, which are of global ecological importance and exhibit broad climatic and elevational gradients, we asked whether grazing effects are pronounced in humid regions, while climate controls are overriding grazing effects in semi-arid regions. LocationTwenty-eight sites across Tibetan pastures, China; 2820-5150m a.s.l. MethodsWe used multivariate analyses and generalized linear mixed models to examine the effects of livestock activity (hotspots with excessive trampling and nutrient input, heavy, moderate and light grazing), habitat (meadow, steppe, steppe-meadow) and their interactions. We focused on plant species composition, richness and concentrations of soil organic carbon (SOC), total N and other plant-available nutrients in soils. Major environmental factors were precipitation, temperature and elevation. Plant indicator species sensitive to trampling and/or grazing were identified. ResultsLivestock grazing changed plant species composition and overall soil fertility across habitats. However, effects were only pronounced in hotspots directly adjacent to herder camps, while differences between grazing intensity levels were weak. Heavy grazing favoured annual species, reduced concentrations of SOC and total N in meadows. The environmental factors that control plant communities and soil condition varied among habitats. Plants and soils were more tightly linked in steppes and steppe-meadows than in meadows. ConclusionsSeveral plant species were identified as frequently and reliably present in hotspots of livestock activity, thus are indicative of intensive trampling and excess plant available nutrient inputs. Overall, plant species composition and soil condition across Tibetan pastures were weakly affected by intensified grazing alone compared to that shaped by environmental factors. This clearly refutes the broadly held perception that increased grazing intensity leads to grassland degradation. Such differing and strong abiotic impacts should be considered in future grassland management and conservation. C1 [Wang, Yun; Seeber, Elke; Wesche, Karsten] Senckenberg Museum Nat Hist Gorlitz, POB 300154, D-02806 Gorlitz, Germany. [Heberling, Gwendolyn; Seeber, Elke] Ernst Moritz Arndt Univ Greifswald, Inst Landscape Ecol, Soldmannstr 15, D-17487 Greifswald, Germany. [Goerzen, Eugen] Univ Kiel, Dept Landscape Ecol, Olshausenstr 75, D-24118 Kiel, Germany. [Miehe, Georg] Philipps Univ Marburg, Fac Geog, Deutschhausstr 10, D-35032 Marburg, Germany. [Wesche, Karsten] German Ctr Integrat Biodivers Res iDiv, Deutsch Pl 5e, D-04103 Leipzig, Germany. [Wesche, Karsten] Tech Univ Dresden, Int Inst Zittau, Markt 23, D-02763 Zittau, Germany. RP Wang, Y (通讯作者)，Senckenberg Museum Nat Hist Gorlitz, POB 300154, D-02806 Gorlitz, Germany. EM yun.wang@senckenberg.de; gwenheb@web.de; eugen.goerzen@gmx.de; miehe@mailer.uni-marburg.de; seeber.elke@gmx.net; karsten.wesche@senckenberg.de TC 48 Z9 50 PD JUL PY 2017 VL 20 IS 3 BP 327 EP 339 DI 10.1111/avsc.12312 UT WOS:000403676000003 DA 2023-03-23 ER PT J AU Zhang, YG Liu, X Cong, J Lu, H Sheng, YY Wang, XL Li, DQ Liu, XD Yin, HQ Zhou, JZ Deng, Y AF Zhang, Yuguang Liu, Xiao Cong, Jing Lu, Hui Sheng, Yuyu Wang, Xiulei Li, Diqiang Liu, Xueduan Yin, Huaqun Zhou, Jizhong Deng, Ye TI The microbially mediated soil organic carbon loss under degenerative succession in an alpine meadow SO MOLECULAR ECOLOGY DT Article AB Land-cover change has long been recognized as having marked effect on the amount of soil organic carbon (SOC). However, the microbially mediated processes and mechanisms on SOC are still unclear. In this study, the soil samples in a degenerative succession from alpine meadow to alpine steppe meadow in the Qing-hai-Tibetan Plateau were analysed using high-throughput technologies, including Illumina sequencing and GEOCHIP functional gene arrays. The soil microbial community structure and diversity were significantly (p<.05) different between alpine meadow and alpine steppe meadow; the microbial.-diversity in alpine steppe meadow was significantly (p<.01) higher than in alpine meadow. Molecular ecological network analysis indicated that the microbial community structure in alpine steppe meadow was more complex and tighter than in the alpine meadow. The relative abundance of soil microbial labile carbon degradation genes (e.g., pectin and hemicellulose) was significantly higher in alpine steppe meadow than in alpine meadow, but the relative abundance of soil recalcitrant carbon degradation genes (e.g., chitin and lignin) showed the opposite tendency. The Biolog Ecoplate experiment showed that microbially mediated soil carbon utilization was more active in alpine steppe meadow than in alpine meadow. Consequently, more soil labile carbon might be decomposed in alpine steppe meadow than in alpine meadow. Therefore, the degenerative succession of alpine meadow because of climate change or anthropogenic activities would most likely decrease SOC and nutrients medicated by changing soil microbial community structure and their functional potentials for carbon decomposition. C1 [Zhang, Yuguang; Liu, Xiao; Cong, Jing; Lu, Hui; Sheng, Yuyu; Wang, Xiulei; Li, Diqiang] Chinese Acad Forestry, Inst Forest Ecol Environm & Protect, Beijing, Peoples R China. [Zhang, Yuguang; Liu, Xiao; Cong, Jing; Lu, Hui; Sheng, Yuyu; Wang, Xiulei; Li, Diqiang] Key Lab Forest Ecol & Environm State Forestry Adm, Beijing, Peoples R China. [Cong, Jing; Liu, Xueduan; Yin, Huaqun] Cent S Univ, Sch Minerals Proc & Bioengn, Changsha, Hunan, Peoples R China. [Lu, Hui] Minzu Univ China, Coll Life & Environm Sci, Beijing, Peoples R China. [Zhou, Jizhong] Univ Oklahoma, Inst Environm Genom, Dept Bot & Microbiol, Norman, OK 73019 USA. [Deng, Ye] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, CAS Key Lab Environm Biotechnol, Beijing, Peoples R China. [Deng, Ye] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China. RP Zhang, YG (通讯作者)，Chinese Acad Forestry, Inst Forest Ecol Environm & Protect, Beijing, Peoples R China.; Zhang, YG (通讯作者)，Key Lab Forest Ecol & Environm State Forestry Adm, Beijing, Peoples R China.; Deng, Y (通讯作者)，Chinese Acad Sci, Res Ctr Ecoenvironm Sci, CAS Key Lab Environm Biotechnol, Beijing, Peoples R China. EM yugzhang@sina.com.cn; yedeng@rcees.ac.cn TC 15 Z9 27 PD JUL PY 2017 VL 26 IS 14 BP 3676 EP 3686 DI 10.1111/mec.14148 UT WOS:000404618000009 DA 2023-03-23 ER PT J AU Liu, SL Cheng, FY Dong, SK Zhao, HD Hou, XY Wu, X AF Liu, Shiliang Cheng, Fangyan Dong, Shikui Zhao, Haidi Hou, Xiaoyun Wu, Xue TI Spatiotemporal dynamics of grassland aboveground biomass on the Qinghai-Tibet Plateau based on validated MODIS NDVI SO SCIENTIFIC REPORTS DT Article AB Spatiotemporal dynamics of aboveground biomass (AGB) is a fundamental problem for grassland environmental management on the Qinghai-Tibet Plateau (QTP). Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) data can feasibly be used to estimate AGB at large scales, and their precise validation is necessary to utilize them effectively. In our study, the clip-harvest method was used at 64 plots in QTP grasslands to obtain actual AGB values, and a handheld hyperspectral spectrometer was used to calculate field-measured NDVI to validate MODIS NDVI. Based on the models between NDVI and AGB, AGB dynamics trends during 2000-2012 were analyzed. The results showed that the AGB in QTP grasslands increased during the study period, with 70% of the grasslands undergoing increases mainly in the Qinghai Province. Also, the meadow showed a larger increasing trend than steppe. Future AGB dynamic trends were also investigated using a combined analysis of the slope values and the Hurst exponent. The results showed high sustainability of AGB dynamics trends after the study period. Predictions indicate 60% of the steppe and meadow grasslands would continue to increase in AGB, while 25% of the grasslands would remain in degradation, with most of them distributing in Tibet. C1 [Liu, Shiliang; Cheng, Fangyan; Dong, Shikui; Zhao, Haidi; Hou, Xiaoyun; Wu, Xue] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. RP Liu, SL; Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM shiliangliu@bnu.edu.cn; dongshikui@sina.com TC 65 Z9 70 PD JUN 23 PY 2017 VL 7 AR 4182 DI 10.1038/s41598-017-04038-4 UT WOS:000404118700072 DA 2023-03-23 ER PT J AU Qi, Q Zhao, MX Wang, SP Ma, XY Wang, YX Gao, Y Lin, QY Li, XZ Gu, BH Li, GX Zhou, JZ Yang, YF AF Qi, Qi Zhao, Mengxin Wang, Shiping Ma, Xingyu Wang, Yuxuan Gao, Ying Lin, Qiaoyan Li, Xiangzhen Gu, Baohua Li, Guoxue Zhou, Jizhong Yang, Yunfeng TI The Biogeographic Pattern of Microbial Functional Genes along an Altitudinal Gradient of the Tibetan Pasture SO FRONTIERS IN MICROBIOLOGY DT Article AB As the highest place of the world, the Tibetan plateau is a fragile ecosystem. Given the importance of microbial communities in driving soil nutrient cycling, it is of interest to document the microbial biogeographic pattern here. We adopted a microarray-based tool named GeoChip 4.0 to investigate grassland microbial functional genes along an elevation gradient from 3200 to 3800 m above sea level open to free grazing by local herdsmen and wild animals. Interestingly, microbial functional diversities increase with elevation, so does the relative abundances of genes associated with carbon degradation, nitrogen cycling, methane production, cold shock and oxygen limitation. The range of Shannon diversities (10.27-10.58) showed considerably smaller variation than what was previously observed at ungrazed sites nearby (9.95-10.65), suggesting the important role of livestock grazing on microbial diversities. Closer examination showed that the dissimilarity of microbial community at our study sites increased with elevations, revealing an elevation-decay relationship of microbial functional genes. Both microbial functional diversity and the number of unique genes increased with elevations. Furthermore, we detected a tight linkage of greenhouse gas (CO2) and relative abundances of carbon cycling genes. Our biogeographic study provides insights on microbial functional diversity and soil biogeochemical cycling in Tibetan pastures. C1 [Qi, Qi; Zhao, Mengxin; Ma, Xingyu; Gao, Ying; Zhou, Jizhong; Yang, Yunfeng] Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing, Peoples R China. [Wang, Shiping] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing, Peoples R China. [Wang, Yuxuan] Tsinghua Univ, Dept Earth Syst Sci, Beijing, Peoples R China. [Wang, Yuxuan] Univ Houston, Dept Earth & Atmospher Sci, Houston, TX USA. [Lin, Qiaoyan] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Northwest Inst Plateau Biol, Xining, Peoples R China. [Li, Xiangzhen] Chinese Acad Sci, Environm Microbiol Key Lab Sichuan Prov, Key Lab Environm & Appl Microbiol, Chengdu Inst Biol, Chengdu, Peoples R China. [Gu, Baohua] Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. [Li, Guoxue] China Agr Univ, Coll Resources & Environm Sci, Beijing, Peoples R China. [Zhou, Jizhong] Univ Oklahoma, Inst Environm Genom, Norman, OK 73019 USA. [Zhou, Jizhong] Univ Oklahoma, Dept Microbiol & Plant Biol, Norman, OK 73019 USA. [Zhou, Jizhong] Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA USA. [Zhou, Jizhong] Tsinghua Univ, Sch Environm, Collaborat Innovat Ctr Reg Environm Qual, Beijing, Peoples R China. RP Yang, YF (通讯作者)，Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing, Peoples R China. EM yangyf@tsinghua.edu.cn TC 18 Z9 19 PD JUN 13 PY 2017 VL 8 AR 976 DI 10.3389/fmicb.2017.00976 UT WOS:000403138000001 DA 2023-03-23 ER PT J AU Chen, BX Zhang, XZ Sun, YF Wang, JS He, YT AF Chen Bao-Xiong Zhang Xian-Zhou Sun Yu-Fang Wang Jing-Sheng He Yong-Tao TI Alpine grassland fPAR change over the Northern Tibetan Plateau from 2002 to 2011 SO ADVANCES IN CLIMATE CHANGE RESEARCH DT Article AB In this study, two different methods including Digital Camera and Reference Panel (DCRP) and traditional in situ fPAR observation for measuring the in situ point fPAR of very short alpine grass vegetation were compared, and the Moderate Resolution Imaging Spectroradiometer (MODIS) fPAR products were evaluated and validated by in situ point data on the alpine grassland over the Northern Tibetan Plateau, which is sensitive to climate change and vulnerable to anthropogenic activities. Results showed that the MODIS alpine grassland fPAR product, examined by using DCRP, and traditional in situ fPAR observation had a significant relationship at the spatial and temporal scales. The decadal MODIS fPAR trend analysis showed that, average growing season fPAR increased by 1.2 x 10(-4) per year and in total increased 0.86% from 2002 to 2011 in alpine grassland, when most of the fPAR increments occurred in southeast and center of the Northern Tibetan Plateau, the alpine grassland tended to recover from degradation slightly. However, climatic factors have influenced the various alpine grassland vegetation fPAR over a period of 10 years; precipitation significantly affected the alpine meadow fPAR in the eastern region, whereas temperature considerably influenced the alpine desert steppe fPAR in the west region. These findings suggest that the regional heterogeneity in alpine grassland fPAR results from various environmental factors, except for vegetation characteristics, such as canopy structure and leaf area. C1 [Chen Bao-Xiong; Sun Yu-Fang] Minist Agr Peoples Republ China, Rural Energy & Environm Agcy, Beijing 100125, Peoples R China. [Zhang Xian-Zhou; Wang Jing-Sheng; He Yong-Tao] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. RP Chen, BX (通讯作者)，Minist Agr Peoples Republ China, Rural Energy & Environm Agcy, Beijing 100125, Peoples R China. EM cbxiong@126.com TC 3 Z9 5 PD JUN PY 2017 VL 8 IS 2 BP 108 EP 116 DI 10.1016/j.accre.2017.05.008 UT WOS:000413286200006 DA 2023-03-23 ER PT J AU Hu, L Zi, HB Ade, L Lerdau, M Wang, CT AF Hu, Lei Zi, HongBiao Ade, LuJi Lerdau, Manuel Wang, ChangTing TI Effects of zokors (Myospalax baileyi) on plant, on abiotic and biotic soil characteristic of an alpine meadow SO ECOLOGICAL ENGINEERING DT Article AB The population of plateau zokor (Myospalax baileyi) has markedly increased on the degraded alpine meadow of Qinghai-Tibetan plateau. Zokors build mounds that alter plant and soil nutrients as well as biotic communities. This study explored changes in biotic and abiotic features of the community on zokor mounds of different ages (one year, and five-six year, referred to as ZM-1, and ZM-5-6) and undisturbed alpine meadow (CM) in the eastern Qinghai-Tibetan Plateau. Significant difference of four plant functional groups on the CM, ZM-1 and ZM-5-6 indicated the grass and sedge plants have led the recovery, and the forb plants lag behind the legumes in the process of restoration in disturbed alpine meadow. Redundancy analysis (RDA) identified that variance in soil microbial communities are mainly explained by the interacting effects of soil physicochemical properties and plant community characteristics. The results also demonstrate that influence of zokors on alpine meadow restoration is complex. While it is clear that intermediate concentrations of zokors appear to enhance the recovery process, it is also clear that the positive feedback between degradation and zokor population dynamics can lead to zokor population levels that cause degradation and retard recovery. A management challenge then becomes how to maintain these intermediate zokor populations and thus maximize meadow recovery. (C) 2017 Elsevier B.V. All rights reserved. C1 [Hu, Lei] Nanjing Univ, Sch Life Sci, Nanjing 210093, Jiangsu, Peoples R China. [Hu, Lei; Zi, HongBiao; Ade, LuJi; Wang, ChangTing] Southwest Univ Nationalities, Coll Life Sci & Technol, First Ring Rd, Chengdu 610041, Peoples R China. [Lerdau, Manuel] Univ Virginia, Dept Environm Sci, Charlottesville, VA 92697 USA. [Lerdau, Manuel] Univ Virginia, Dept Biol, Charlottesville, VA 92697 USA. RP Wang, CT (通讯作者)，Southwest Univ Nationalities, Coll Life Sci & Technol, First Ring Rd, Chengdu 610041, Peoples R China. EM wangct6@163.com TC 12 Z9 15 PD JUN PY 2017 VL 103 BP 95 EP 105 DI 10.1016/j.ecoleng.2017.03.010 PN A UT WOS:000402830200010 DA 2023-03-23 ER PT J AU Lu, QS Ning, JC Liang, FY Bi, XL AF Lu, Qingshui Ning, Jicai Liang, Fuyuan Bi, Xiaoli TI Evaluating the Effects of Government Policy and Drought from 1984 to 2009 on Rangeland in the Three Rivers Source Region of the Qinghai-Tibet Plateau SO SUSTAINABILITY DT Article AB The Three Rivers Source Region of the Qinghai-Tibet Plateau is a key area that has extensive impacts on much of the population and economy of China as well as several Southeast Asian countries. The rangeland in this area has undergone degradation, the driving factors of which have been extensively investigated in previous studies. However, the effect of policy on rangeland was not analyzed by subdividing the study period according to the timing of the rangeland policies. The role of dry conditions during the process of degradation has not been studied. Therefore, the period from 1984 to 2009 was subdivided into five periods according to the timing of the relevant government policies based on long-term field investigation. The mean annual normalized difference vegetation index (NDVI) and its relationship to dry conditions, policy, temperature, precipitation, and moisture index were analyzed for the five periods. According to our analysis, dry conditions mainly occurred in non-vegetation-growing months, and they did not affect the status of the rangeland. The privatization of rangeland and livestock caused the number of livestock to increase, resulting in a decrease in the mean annual NDVI from 1984 to 1993. The policies of "Green-to-Grain" and eco-migration caused livestock numbers to decrease and the NDVI to increase after 1994. Physical factors such as temperature, precipitation, and moisture also affected the status of the rangeland. Increased temperature had positive effects on rangeland in most areas, but its effect was offset by increased numbers of livestock from 1984 to 1993. Precipitation had positive effects only in drier areas in which the precipitation in the vegetation-growing months was less than 400 mm. In general, the policies of "Green-to-Grain" and eco-migration improved the status of rangeland, and helped improve sustainable use of the rangeland. The methods used in this study could be applied to other case studies of rangeland. Governments should continue to implement compensation policies to maintain the improved condition of rangeland in the area and expand those policies to other rangeland areas. C1 [Lu, Qingshui] Univ Jinan, Inst Green Dev, Jinan 250022, Peoples R China. [Ning, Jicai; Bi, Xiaoli] Chinese Acad Sci, Yantai Inst Coastal Zone Res, Yantai 264003, Peoples R China. [Liang, Fuyuan] Western Illinois Univ, Macomb, IL 61455 USA. RP Ning, JC (通讯作者)，Chinese Acad Sci, Yantai Inst Coastal Zone Res, Yantai 264003, Peoples R China. EM sm_luqs@ujn.edu.cn; jcning@yic.ac.cn; f-liang@wiu.edu; xlbi@yic.ac.cn TC 7 Z9 7 PD JUN PY 2017 VL 9 IS 6 AR 1033 DI 10.3390/su9061033 UT WOS:000404133200164 DA 2023-03-23 ER PT J AU Niu, B He, YT Zhang, XZ Du, MY Shi, PL Sun, W Zhang, LM AF Niu, Ben He, Yongtao Zhang, Xianzhou Du, Mingyuan Shi, Peili Sun, Wei Zhang, Leiming TI CO2 Exchange in an Alpine Swamp Meadow on the Central Tibetan Plateau SO WETLANDS DT Article AB Alpine wetland on the Qinghai-Tibetan Plateau holds the highest organic carbon density of plateau ecosystems and is among the most sensitive areas to climate change. Understanding CO2 exchange and its environmental forces in this specific ecosystem can benefit constraints of carbon budgets from site to global scale under future climate change. Here we investigated CO2 flux measurements from 2009 to 2013 in a wide-distributed alpine wetland, Kobresia littledalei-Blysmus sinocompressus swamp meadow, by eddy covariance (EC) on the central Tibetan Plateau. Results showed diurnal variation of net ecosystem CO2 exchange (NEE) was affected by photosynthetically active radiation (PAR), and this alpine swamp meadow had a high maximum ecosystem photosynthesis rate (Amax) with 32.96 mu mol CO2 m(-2) s(-1). Nighttime ecosystem respiration (Re) rates were well associated with temperature, and average annual temperature sensitivity of Re (Q(10)) was 3.2. Both temperature and relative humidity (RH) played key roles in regulations of seasonal NEE, and their interactive effect was only significant in GS, especially when soil temperature at 10 cm was above 6.3 degrees C. Our results suggested this alpine swamp meadow was a stable CO2 sink with an annual accumulation of - 161.85 +/- 28.02 g C m(-2). However, response of annual Re was more sensitive than GPP to change of temperature and length of growing season (LOG), which implied that future climate warming likely to weaken the CO2 sink of this alpine swamp meadow. C1 [Niu, Ben; He, Yongtao; Zhang, Xianzhou; Shi, Peili; Sun, Wei] Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Niu, Ben] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [He, Yongtao; Zhang, Xianzhou; Shi, Peili] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. [Du, Mingyuan] Natl Agr & Food Res Org, Inst Agroenvironm Sci, 3-1-3 Kannondai, Tsukuba, Ibaraki 3058604, Japan. [Zhang, Leiming] Chinese Acad Sci, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. RP He, YT (通讯作者)，Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China.; He, YT (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100190, Peoples R China. EM heyt@igsnrr.ac.cn TC 22 Z9 26 PD JUN PY 2017 VL 37 IS 3 BP 525 EP 543 DI 10.1007/s13157-017-0888-2 UT WOS:000403573000011 DA 2023-03-23 ER PT J AU Pu, Y Wang, CF Meyers, PA AF Pu, Yang Wang, Canfa Meyers, Philip A. TI Origins of biomarker aliphatic hydrocarbons in sediments of alpine Lake Ximencuo, China SO PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY DT Article AB Aliphatic hydrocarbons in lake sediments are important lipid biomarkers that have been widely used in paleoenvironmental reconstructions on the dual premises that their sources are defined and that they resist degradation. As a test of these premises, we have analyzed the n-alkane and n-alkene distributions in the leaf waxes of the eight dominant plants and in the surface soil at five locations surrounding Lake Ximencuo, a typical alpine lake on the eastern Qinghai-Tibetan Plateau, to explore the origins, delivery, and deposition of these molecular biomarkers in the surface sediment of this restricted lake system. Distinctive distributions of n-alkanes and n-alkenes were found in the leaf waxes of the different plants. Unlike those of the plants, the n-alkane distributions in the soil are virtually identical at the locations around the lake, and the n-alkenes found in the plant waxes are rare in the surface soil. These differences imply extensive diagenetic degradation of the soil-hosted hydrocarbons. In contrast to the soils, the hydrocarbon distribution in the lake sediment is more like those of the plants. It contains n-alkanes that range from C-15 to C-33 with a maximum abundance at n-C-31 and includes a suite of n-C-21:1 to n-C-28:1 alkenes with odd-carbon preference. Although they may originate from land-plant debris that is washed directly into the lake, the alkenes are postulated to originate principally from algae living in the lake because of their absence in the soils. The biomarker hydrocarbons in the lake sediments appear to integrate multiple inputs, including plants around the lake, glacial meltwaters, and algae, fungi, and microbes within the lake. The results of this study highlight that different groups of aliphatic hydrocarbons in lake sediments can have different origins and consequently are likely to reflect different aspects of past environmental conditions. Hence, consideration of the multiple possible origins of these biomarkers has the potential to expand and refine paleoenvironmental reconstructions that employ them. (C) 2017 Elsevier B.V. All rights reserved. C1 [Pu, Yang] Nanjing Univ Informat Sci & Technol, Sch Geog & Remote Sensing, Nanjing 210044, Jiangsu, Peoples R China. [Pu, Yang] Nanjing Univ, Dept Earth Sci, MOE, Key Lab Surficial Geochem, 163 Xianlindadao, Nanjing 210046, Jiangsu, Peoples R China. [Wang, Canfa] China Univ Geosci, State Key Lab Biogeol & Environm Geol, Wuhan 430074, Peoples R China. [Meyers, Philip A.] Univ Michigan, Dept Earth & Environm Sci, 1100 North Univ Ave, Ann Arbor, MI 48109 USA. RP Meyers, PA (通讯作者)，Univ Michigan, Dept Earth & Environm Sci, 1100 North Univ Ave, Ann Arbor, MI 48109 USA. EM pameyers@umich.edu TC 10 Z9 11 PD JUN 1 PY 2017 VL 475 BP 106 EP 114 DI 10.1016/j.palaeo.2017.03.011 UT WOS:000400532500009 DA 2023-03-23 ER PT J AU Li, J Liu, D Wang, T Li, YN Wang, SP Yang, YT Wang, XY Guo, H Peng, SS Ding, JZ Shen, MG Wang, L AF Li, Jia Liu, Dan Wang, Tao Li, Yingnian Wang, Shiping Yang, Yuting Wang, Xiaoyi Guo, Hui Peng, Shushi Ding, Jinzhi Shen, Miaogen Wang, Lei TI Grassland restoration reduces water yield in the headstream region of Yangtze River SO SCIENTIFIC REPORTS DT Article AB Large-scale ecological restoration programs are considered as one of the key strategies to enhance ecosystem services. The Headstream region of Yangtze River (HYZR), which is claimed to be China's Water Tower but witnessed the rapid grassland deterioration during 1970s-2000, has seen a series of grassland restoration programs since 2000. But few studies have thoroughly estimated the hydrological effect of this recent grassland restoration. Here we show that restoration significantly reduces growing-season water yield coefficient (WYC) from 0.37 +/- 0.07 during 1982-1999 to 0.24 +/- 0.07 during 2000-2012. Increased evapotranspiration (ET) is identified as the main driver for the observed decline in WYC. After factoring out climate change effects, vegetation restoration reduces streamflow by 9.75 +/- 0.48 mm from the period 1982-1999 to the period 2000-2012, amounting to 16.4 +/- 0. 80% of climatological growing-season streamflow. In contrary to water yield, restoration is conducive to soil water retention-an argument that is supported by long-term in-situ grazing exclusion experiment. Grassland restoration therefore improves local soil water conditions but undercuts gain in downstream water resources associated with precipitation increases. C1 [Li, Jia; Wang, Tao; Wang, Shiping; Shen, Miaogen; Wang, Lei] Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100085, Peoples R China. [Li, Jia; Liu, Dan; Wang, Tao; Wang, Shiping; Wang, Xiaoyi; Guo, Hui; Ding, Jinzhi; Shen, Miaogen; Wang, Lei] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100085, Peoples R China. [Li, Yingnian] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810001, Peoples R China. [Li, Yingnian] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. [Yang, Yuting] CSIRO Land & Water, Canberra, ACT, Australia. [Peng, Shushi] Univ Versailles St Quentin En Yvelines, CNRS, Commissariat Energie Atom, Lab Sci Climat & Environm, F-91191 Gif Sur Yvette, France. RP Wang, T (通讯作者)，Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100085, Peoples R China.; Wang, T (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100085, Peoples R China.; Li, YN (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810001, Peoples R China.; Li, YN (通讯作者)，Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. EM twang@itpcas.ac.cn; ynli@nwipb.cas.cn TC 37 Z9 39 PD MAY 19 PY 2017 VL 7 AR 2162 DI 10.1038/s41598-017-02413-9 UT WOS:000401614900020 DA 2023-03-23 ER PT J AU Ma, ZY Liu, HY Mi, ZR Zhang, ZH Wang, YH Xu, W Jiang, L He, JS AF Ma, Zhiyuan Liu, Huiying Mi, Zhaorong Zhang, Zhenhua Wang, Yonghui Xu, Wei Jiang, Lin He, Jin-Sheng TI Climate warming reduces the temporal stability of plant community biomass production SO NATURE COMMUNICATIONS DT Article AB Anthropogenic climate change has emerged as a critical environmental problem, prompting frequent investigations into its consequences for various ecological systems. Few studies, however, have explored the effect of climate change on ecological stability and the underlying mechanisms. We conduct a field experiment to assess the influence of warming and altered precipitation on the temporal stability of plant community biomass in an alpine grassland located on the Tibetan Plateau. We find that whereas precipitation alteration does not influence biomass temporal stability, warming lowers stability through reducing the degree of species asynchrony. Importantly, biomass temporal stability is not influenced by plant species diversity, but is largely determined by the temporal stability of dominant species and asynchronous population dynamics among the coexisting species. Our findings suggest that ongoing and future climate change may alter stability properties of ecological communities, potentially hindering their ability to provide ecosystem services for humanity. C1 [Ma, Zhiyuan; Liu, Huiying; Wang, Yonghui; Xu, Wei; He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. [Ma, Zhiyuan; Liu, Huiying; Wang, Yonghui; Xu, Wei; He, Jin-Sheng] Peking Univ, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China. [Mi, Zhaorong; Zhang, Zhenhua; He, Jin-Sheng] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Jiang, Lin] Georgia Inst Technol, Sch Biol Sci, Atlanta, GA 30332 USA. [Mi, Zhaorong] Chinese Acad Agr Sci, Farmland Irrigat Res Inst, Xinxiang 453002, Peoples R China. [Wang, Yonghui] Inner Mongolia Univ, Dept Ecol, Coll Life Sci, Hohhot 010021, Peoples R China. RP He, JS (通讯作者)，Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China.; He, JS (通讯作者)，Peking Univ, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China.; He, JS (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China.; Jiang, L (通讯作者)，Georgia Inst Technol, Sch Biol Sci, Atlanta, GA 30332 USA. EM lin.jiang@biology.gatech.edu; jshe@pku.edu.cn TC 518 Z9 558 PD MAY 10 PY 2017 VL 8 AR 15378 DI 10.1038/ncomms15378 UT WOS:000400888300001 DA 2023-03-23 ER PT J AU Pan, T Hou, S Wu, SH Liu, YJ Liu, YH Zou, XT Herzberger, A Liu, JG AF Pan, Tao Hou, Shuai Wu, Shaohong Liu, Yujie Liu, Yanhua Zou, Xintong Herzberger, Anna Liu, Jianguo TI Variation of soil hydraulic properties with alpine grassland degradation in the eastern Tibetan Plateau SO HYDROLOGY AND EARTH SYSTEM SCIENCES DT Article AB Ecosystems in alpine mountainous regions are vulnerable and easily disturbed by global environmental change. Alpine swamp meadow, a unique grassland type in the eastern Tibetan Plateau that provides important ecosystem services to the upstream and downstream regions of international rivers of Asia and other parts of the world, is undergoing severe degradation, which can dramatically alter soil hydraulic properties and water cycling processes. However, the effects of alpine swamp meadow degradation on soil hydraulic properties and the corresponding influencing mechanisms are still poorly understood. In this study, soil moisture content (SMC), field capacity (FC) and saturated hydraulic conductivity (K-s) together with several basic soil properties under lightly degraded (LD), moderately degraded (MD) and severely degraded (SD) alpine swamp meadow were investigated; the variations in SMC, FC and K-s with alpine swamp meadow degradation and their dominant influencing factors were analysed. The results showed that SMC and FC decreased consistently from LD to SD, while K-s decreased from LD to MD and then increased from MD to SD, following the order of LD > SD > MD. Significant differences in soil hydraulic properties between degradation degrees were found in the upper soil layers (0-20 cm), indicating that the influences of degradation were most pronounced in the top-soils. FC was positively correlated with capillary porosity, water-stable aggregates, soil organic carbon, and silt and clay content; K-s was positively correlated with non-capillary porosity (NCP). Relative to other soil properties, soil porosity is the dominant factor influencing FC and K-s. Capillary porosity explained 91.1% of total variance in FC, and NCP explained 97.3% of total variance in K-s. The combined effect of disappearing root activities and increasing sand content was responsible for the inconsistent patterns of NCP and K-s. Our findings suggest that alpine swamp meadow degradation would inevitably lead to reduced water holding capacity and rainfall infiltration. This study provides a more comprehensive understanding of the soil hydrological effects of vegetation degradation. Further hydrological modelling studies in the Tibetan Plateau and similar regions are recommended to understand the effects of degraded alpine swamp meadows on soil hydraulic properties. C1 [Pan, Tao; Hou, Shuai; Wu, Shaohong; Liu, Yujie; Liu, Yanhua; Zou, Xintong] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Hou, Shuai; Zou, Xintong] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Pan, Tao; Herzberger, Anna; Liu, Jianguo] Michigan State Univ, Ctr Syst Integrat & Sustainabil, Dept Fisheries & Wildlife, E Lansing, MI 48824 USA. RP Liu, YJ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM liuyujie@igsnrr.ac.cn TC 48 Z9 52 PD MAY 2 PY 2017 VL 21 IS 4 BP 2249 EP 2261 DI 10.5194/hess-21-2249-2017 UT WOS:000400516200001 DA 2023-03-23 ER PT J AU Chen, XP Wang, GX Zhang, T Mao, TX Wei, D Hu, ZY Song, CL AF Chen, Xiaopeng Wang, Genxu Zhang, Tao Mao, Tianxu Wei, Da Hu, Zhaoyong Song, Chunlin TI Effects of warming and nitrogen fertilization on GHG flux in the permafrost region of an alpine meadow SO ATMOSPHERIC ENVIRONMENT DT Article AB The limited number of in situ measurements of greenhouse gas (GHG) flux during soil freeze-thaw cycles in permafrost regions limits our ability to accurately predict how the alpine ecosystem carbon sink or source function will vary under future warming and increased nitrogen (N) deposition. An alpine meadow in the permafrost region of the Qinghai-Tibet Plateau was selected, and a simulated warming with N fertilization experiment was carried out to investigate the key GHG fluxes (ecosystem respiration [Re], CH4 and N2O) in the early (EG), mid (MG) and late (LG) growing seasons. The results showed that: (i) warming (4.5 degrees C) increased the average seasonal Re, CH4 uptake and N2O emission by 73.5%, 65.9% and 431.6%, respectively. N fertilization (4 g N m(-2)) alone had no significant effect on GHG flux; the interaction of warming and N fertilization enhanced CH4 uptake by 10.3% and N2O emissions by 27.2% than warming, while there was no significant effect on the Re; (ii) the average seasonal fluxes of Re, CH4 and N2O were MG > LG > EG, and Re and CH4 uptake were most sensitive to the soil freezing process instead of soil thawing process; (iii) surface soil temperature was the main driving factor of the Re and CH4 fluxes, and the N2O flux was mainly affected by daily rainfall; (iv) in the growing season, warming increased greenhouse warming potential (GWP) of the alpine meadow by 74.5%, the N fertilization decreased GWP of the warming plots by 13.9% but it was not statistically significant. These results indicate that (i) relative to future climate warming (or permafrost thawing), there could be a hysteresis of GHG flux in the alpine meadow of permafrost region; (ii) under the scenario of climate warming, increasing N deposition has limited impacts on the feedback of GHG flux of the alpine meadow. (C) 2017 Elsevier Ltd. All rights reserved. C1 [Chen, Xiaopeng; Wang, Genxu; Zhang, Tao; Mao, Tianxu; Wei, Da; Hu, Zhaoyong; Song, Chunlin] Chinese Acad Sci, Key Lab Mt Environm Evolvement & Regulat, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Chen, Xiaopeng; Zhang, Tao; Mao, Tianxu; Song, Chunlin] Univ Chinese Acad Sci, Beijing 100039, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Key Lab Mt Environm Evolvement & Regulat, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM wanggx@imde.ac.cn TC 51 Z9 57 PD MAY PY 2017 VL 157 BP 111 EP 124 DI 10.1016/j.atmosenv.2017.03.024 UT WOS:000400217900012 DA 2023-03-23 ER PT J AU Gu, YF Wang, YY Xiang, QJ Yu, XM Zhao, K Zhang, XP Lindstrom, K Hu, YF Liu, SQ AF Gu Yunfu Wang, Yingyan Xiang, Quanju Yu, Xiumei Zhao, Ke Zhang, Xiaoping Lindstrom, Kristina Hu Yufu Liu, Songqing TI Implications of wetland degradation for the potential denitrifying activity and bacterial populations with nirS genes as found in a succession in Qinghai Tibet plateau, China SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB Alpine wetland in the Zoige Plateau has suffered from serious degradation during"the last 30 years due to global climate change and anthropogenic impact. Denitrification is a key nitrogen removal process which can be performed by different microorganisms, including bacteria harboring ttirS-genes. In this study, a degradation succession was used to study the effect on potential denitrification activity (PDA) and on bacterial communities harboring nirS genes. Based on the determination of the PDA, the abundance, structural diversity, and phylogenetic identity of the soil bacteria with nirS genes were further assessed by qPCR, terminal restriction fragment length polymorphism (T-RFLP), and DNA-sequencing, respectively. The results showed that soil PDA ranged from 8.78 to 52.77 ng N20-N g(-1) dry soil h(-1), being lowest in sandy soil and highest in swamp soil. The abundance of nirS genes (copies g(-1) soil) were also the lowest in the sandy soil while highest in the swamp soil. The average Shannon-Wiener diversity index of the nirS denitrifying bacterial structural ranged from 2.20 in the meadow soil to 3.07 in the swamp soil. Redundancy analysis (RDA) showed that the nirS denitrifying bacterial community correlated with soil water content and available phosphorus, with water content as the major factor in shaping the nirS denitrifying bacterial community. The results of this study suggest that the wetland degradation would decrease soil PDA, and abundance and structural diversity of the denitrifying bacteria with nirS genes. These findings can contribute to support a theoretical foundation for predicting the potential influences of wetland degradation on soil denitrifying bacteria in alpine wetlands. (C) 2017 Elsevier Masson SAS. All rights reserved. C1 [Gu Yunfu; Wang, Yingyan; Xiang, Quanju; Yu, Xiumei; Zhao, Ke; Zhang, Xiaoping; Hu Yufu] Sichuan Agr Univ, Dept Microbiol, Coll Resource Sci & Technol, Chengdu 611130, Peoples R China. [Lindstrom, Kristina] Univ Helsinki, Dept Environm Sci, FIN-00014 Helsinki, Finland. [Liu, Songqing] Chengdu Normal Univ, Dept Microbiol, Coll Chem & Life Sci, Chengdu 611130, Peoples R China. RP Gu, YF (通讯作者)，Sichuan Agr Univ, Dept Microbiol, Coll Resource Sci & Technol, Chengdu 611130, Peoples R China. EM guyf@sicau.edu.cn TC 16 Z9 18 PD MAY-JUN PY 2017 VL 80 BP 19 EP 26 DI 10.1016/j.ejsobi.2017.03.005 UT WOS:000404704700003 DA 2023-03-23 ER PT J AU Hu, YF Jiang, SL Yuan, S Deng, LJ Xiao, HH Shu, XY Chen, GD Xia, JG AF Hu, Yu-Fu Jiang, Shuang-Long Yuan, Shu Deng, Liang-Ji Xiao, Hai-Hua Shu, Xiang-Yang Chen, Guang-Deng Xia, Jian-Guo TI Changes in soil organic carbon and its active fractions in different desertification stages of alpine-cold grassland in the eastern Qinghai-Tibet Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB In recent years, the desertification of alpine-cold grasslands has become increasingly serious in the Qinghai-Tibet Plateau in China, but it has not received the same amount of attention as has desertification in (semi) arid areas. Little is thus known about the change in soil organic carbon (SOC) during alpine-cold grassland desertification. To quantify the impacts of desertification on vegetation, SOC and its active fractions in alpine-cold grasslands, areas of light desertified grassland, medium desertified grassland, heavy desertified grassland, serious desertified grassland, and nondesertified grassland were selected as experimental sites in the eastern Qinghai-Tibet Plateau in China. The species number, height and coverage of vegetation were surveyed, and the soil particle fractions, SOC and SOC active fractions (including dissolved organic carbon (DOC), microbial biomass carbon (MBC), and labile organic carbon (LOC) were measured to a depth of 0-100 cm. The results showed that alpine-cold grassland desertification resulted in a significant reduction in vegetation cover, plant biomass, fine soil particles, SOC, DOC, LOC and MBC. The decreases in DOC, LOC and MBC were more rapid and apparent than were those in SOC, and the decrease in MBC was the most obvious among them. The rates of reduction in SOC concentrations accelerated as desertification progressed; most of the SOC was lost in the middle and later desertification stages, with lower losses during early desertification. The results indicate that active SOC fractions, particularly MBC, are more sensitive to desertification and can be used as sensitive indicators of desertification. Efforts to limit desertification and reduce SOC loss in alpine-cold grasslands should focus on early desertification stages and adopt strategies to prevent overgrazing and control the erosion of soil by wind. C1 [Hu, Yu-Fu; Jiang, Shuang-Long; Yuan, Shu; Deng, Liang-Ji; Xiao, Hai-Hua; Shu, Xiang-Yang; Chen, Guang-Deng; Xia, Jian-Guo] Sichuan Agr Univ, Coll Resources Sci & Technol, Chengdu 611130, Peoples R China. RP Hu, YF (通讯作者)，Sichuan Agr Univ, Coll Resources Sci & Technol, Chengdu 611130, Peoples R China. EM huyufu@sicau.edu.cn TC 12 Z9 16 PD MAY PY 2017 VL 76 IS 9 AR 348 DI 10.1007/s12665-017-6684-8 UT WOS:000401323600020 DA 2023-03-23 ER PT J AU Liu, SB Schleuss, PM Kuzyakov, Y AF Liu, Shibin Schleuss, Per-Marten Kuzyakov, Yakov TI Carbon and Nitrogen Losses from Soil Depend on Degradation of Tibetan Kobresia Pastures SO LAND DEGRADATION & DEVELOPMENT DT Article AB Degradation of Kobresia pygmaea pastures has strongly increased on the Tibetan Plateau over the last few decades and contributed to a high loss of soil organic carbon and nutrients. The pathways of carbon (C) and nitrogen (N) losses from degraded K. pygmaea pastures are still unclear, but this is a prerequisite to assess the recovery of Tibetan grasslands. We investigated the response of day- and nighttime CO2 efflux and leaching of dissolved organic C and N, NH4+ and NO3- from K. pygmaea root mats in three degradation stages: living root mat, dying root mat and dead root mat. Dying root mat had the highest C loss as CO2 and as leached dissolved organic carbon. This indicates K. pygmaea pastures shift from a C sink to a C source following plant death. In contrast, living root mat had the lowest daytime CO2 efflux (038 +/- 01 mu gCg(-1)h(-1)) because CO2 was assimilated via photosynthesis. Nighttime CO2 efflux positively correlated with soil moisture for living and dead root mats. It indicates that increasing precipitation might accelerate C losses due to enhanced soil organic carbon decomposition. Furthermore, dead root mat had the highest average NO3- loss (23 +/- 26mgNL(-1)) from leaching compared with other root mats. Consequently, leaching increases the negative impacts of pasture degradation on N availability in these often N limited ecosystems and thus impedes the recovery of K. pastures following degradation. Copyright (c) 2016 John Wiley & Sons, Ltd. C1 [Liu, Shibin; Schleuss, Per-Marten; Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temp Ecosyst, Busgenweg 2, D-37077 Gottingen, Germany. [Kuzyakov, Yakov] Univ Gottingen, Dept Agr Soil Sci, Busgenweg 2, D-37077 Gottingen, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan 420049, Russia. RP Liu, SB (通讯作者)，Univ Gottingen, Dept Soil Sci Temp Ecosyst, Busgenweg 2, D-37077 Gottingen, Germany. EM sliu3@gwdg.de TC 34 Z9 37 PD MAY PY 2017 VL 28 IS 4 BP 1253 EP 1262 DI 10.1002/ldr.2522 UT WOS:000401322900008 DA 2023-03-23 ER PT J AU Liu, YS Fan, JW Shi, ZJ Yang, XH Harris, W AF Liu, Yanshu Fan, Jiangwen Shi, Zhongjie Yang, Xiaohui Harris, Warwick TI Relationships between plateau pika (Ochotona curzoniae) densities and biomass and biodiversity indices of alpine meadow steppe on the Qinghai-Tibet Plateau China SO ECOLOGICAL ENGINEERING DT Article AB Variations of plant biomass and plant species diversity in relation to plateau pika densities in alpine meadow steppe of the Qinghai-Tibet Plateau China were investigated. Peak above-and below-ground biomass, botanical composition, and soil moisture were measured and from these species and functional diversity indices were calculated with reference to pika burrow densities, biomass and soil moisture. Biomass components generally decreased with increased pika burrow density. Biomass of sedges and forbs increased whereas aboveground biomass of grasses first increased and then decreased as burrow density increased. There were positive linear relationships between aboveground biomass and both species and functional group richness and diversity, and also between soil moisture and these indices. These results are relevant to considerations of whether plateau pika is a pest or is a key species in maintaining the ecological stability and biodiversity of its indigenous habitat. (C) 2017 Elsevier B.V. All rights reserved. C1 [Liu, Yanshu; Shi, Zhongjie; Yang, Xiaohui] Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. [Liu, Yanshu; Fan, Jiangwen] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Harris, Warwick] Landcare Res, POB 40, Lincoln 7640, NE, New Zealand. RP Fan, JW (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM fanjw@igsnrr.ac.cn TC 31 Z9 35 PD MAY PY 2017 VL 102 BP 509 EP 518 DI 10.1016/j.ecoleng.2017.02.026 UT WOS:000399623700054 DA 2023-03-23 ER PT J AU Wu, GL Wang, D Liu, Y Ding, LM Liu, ZH AF Wu Gao-Lin Wang Dong Liu Yu Ding Lu-Ming Liu Zhen-Heng TI Warm-season Grazing Benefits Species Diversity Conservation and Topsoil Nutrient Sequestration in Alpine Meadow SO LAND DEGRADATION & DEVELOPMENT DT Article AB Seasonal grazing is one way of the moderate grazing regimes, but little information is available on compared study of seasonal grazing in alpine meadow. We studied the aboveground and belowground properties among warm-seasonal grazing meadows and cold-seasonal grazing meadows on the Qinghai-Tibetan Plateau. Results showed that the warm-seasonal grazing increased forb functional group proportion, plant density and evenness index but decreased root biomass, plant height and graminoid functional group proportions. Grazing seasons affected variation in soil bulk density, soil water content, pH and soil nutrient content, and the variations caused the various of soil carbon and nitrogen density. The highest values of soil carbon and nitrogen contents and densities in the warm-season grazing meadow occurred at the top 10-cm soil, while the highest values in the cold-season grazing meadow occurred at the depth of 30- to 50-cm soil. Our results indicated that the warm-season grazing is suitable for the species diversity conservation and the nutrient sequestration at the topsoil. However, the cold-season grazing is suitable for the nutrient sequestration at the deep soil. This study implied that the warm-season and cold-season grazing might be exchanged regularly to practice continuous carbon and nitrogen sequestration. Periodic cold-season and warm-season grazing would be the suitable grazing regime to keep alpine meadow sustainability. Copyright (c) 2016 John Wiley & Sons, Ltd. C1 [Wu Gao-Lin; Wang Dong; Liu Yu] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 710020, Shaanxi, Peoples R China. [Wu Gao-Lin; Wang Dong; Liu Yu] Chinese Acad Sci & Minist Water Resources, Inst Soil & Water Conservat, Yangling 710020, Shaanxi, Peoples R China. [Ding Lu-Ming] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Liu Zhen-Heng] Maqu Alpine Grassland Workstn, Maqu 747300, Gansu, Peoples R China. RP Wu, GL (通讯作者)，Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 710020, Shaanxi, Peoples R China. EM gaolinwu@gmail.com TC 37 Z9 40 PD MAY PY 2017 VL 28 IS 4 BP 1311 EP 1319 DI 10.1002/ldr.2536 UT WOS:000401322900013 DA 2023-03-23 ER PT J AU Xu, LX Cao, Y Li, W Cheng, Y Qin, TC Zhou, YC Liu, F AF Xu, Ling-xiang Cao, Yu Li, Wei Cheng, Yu Qin, Tong-chun Zhou, Yuan-chang Liu, Fan TI Maintain Spatial Heterogeneity, Maintain BiodiversityA Seed Bank Study in a Grazed Alpine Fen Meadow SO LAND DEGRADATION & DEVELOPMENT DT Article AB Wetland degradation is a source of anxiety and is more severe in cold regions than other areas. The soil seed bank acts as a propagule source for revegetation to affiliate the restoration of degraded wetlands. However, the effects of this approach are controversial and depend on the traits of the seed bank and its interactions with the environment. The seed bank in an alpine fen meadow was studied to determine its exact role in revegetation. The surveyed shore of a Tibetan lake, Gahai Lake, was divided into three sites under different levels of grazing pressure. Each site was separated into six transects along a water-depth gradient to collect soil cores to determine the pattern of biodiversity through a germination experiment in a greenhouse. After an analysis of heterogeneity-related diversity, partitioning of 58 discovered species indicated that 39.5 could be contributed to beta-diversity, which was mainly contributed to water depth. Overgrazing (0.607 sheep unit/acre, NovemberMarch) decreased seed bank diversity in many respects, especially through decreasing spatial heterogeneity and homogenizing biota. A lightly grazed, well-protected site had not only the highest beta-diversity and species abundance but also the highest inter-site species turnover rate compared with other sites under moderate grazing intensity. Despite the lack of target species, the seed bank serves as (i) a species-rich pool; (ii) an extant legacy seed source for sustaining heterogeneity and floristic diversity; and (iii) an ecological indicator, and its effect can be reinforced by appropriate grazing practices (multiple intensity) and hydrological modifications. Copyright (c) 2016 John Wiley & Sons, Ltd. C1 [Xu, Ling-xiang; Cao, Yu; Li, Wei; Cheng, Yu; Liu, Fan] Chinese Acad Sci, Wuhan Bot Garden, Hubei Key Lab Wetland Evolut & Ecol Restorat, Wuhan 430074, Hubei, Peoples R China. [Xu, Ling-xiang; Cao, Yu; Li, Wei; Cheng, Yu; Liu, Fan] Chinese Acad Sci, Wuhan Bot Garden, Key Lab Aquat Bot & Watershed Ecol, Wuhan 430074, Hubei, Peoples R China. [Xu, Ling-xiang; Zhou, Yuan-chang] Fujian Agr & Forestry Univ, Coll Crop Sci, Fuzhou 350002, Fujian, Peoples R China. [Qin, Tong-chun] China Inst Geoenvironm Monitoring, Beijing 100081, Peoples R China. RP Liu, F (通讯作者)，Chinese Acad Sci, Wuhan Bot Garden, Key Lab Aquat Bot & Watershed Ecol, Wuhan 430074, Hubei, Peoples R China.; Zhou, YC (通讯作者)，Fujian Agr & Forestry Univ, Coll Crop Sci, Fuzhou 350002, Fujian, Peoples R China. EM zwy_2002@163.com; fanliu@wbgcas.cn TC 3 Z9 4 PD MAY PY 2017 VL 28 IS 4 BP 1376 EP 1385 DI 10.1002/ldr.2606 UT WOS:000401322900020 DA 2023-03-23 ER PT J AU Wu, PF Zhang, HZ Cui, LW Wickings, K Fu, SL Wang, CT AF Wu, Pengfei Zhang, Hongzhi Cui, Liwei Wickings, Kyle Fu, Shenglei Wang, Changting TI Impacts of alpine wetland degradation on the composition, diversity and trophic structure of soil nematodes on the Qinghai-Tibetan Plateau SO SCIENTIFIC REPORTS DT Article AB Alpine wetlands on the Qinghai-Tibetan Plateau are undergoing degradation. However, little is known regarding the response of soil nematodes to this degradation. We conducted investigations in a wet meadow (WM), a grassland meadow (GM), a moderately degraded meadow (MDM) and a severely degraded meadow (SDM) from April to October 2011. The nematode community taxonomic composition was similar in the WM, GM and MDM and differed from that in the SDM. The abundance declined significantly from the WM to the SDM. The taxonomic richness and Shannon index were comparable between the WM and MDM but were significantly lower in the SDM, and the Pielou evenness showed the opposite pattern. The composition, abundance and diversity in the WM and SDM were relatively stable over time compared with other habitats. The abundances of all trophic groups, aside from predators, decreased with degradation. The relative abundances of herbivores, bacterivores, predators and fungivores were stable, while those of omnivores and algivores responded negatively to degradation. Changes in the nematode community were mainly driven by plant species richness and soil available N. Our results demonstrate that alpine wetland degradation significantly affects the soil nematode communities, suppressing but not shifting the main energy pathways through the soil nematode communities. C1 [Wu, Pengfei; Zhang, Hongzhi; Cui, Liwei; Wang, Changting] Southwest Univ Nationalities, Coll Life Sci & Technol, Chengdu 610041, Peoples R China. [Wickings, Kyle] Cornell Univ, Dept Entomol, New York State Agr & Expt Stn, Geneva, NY 14456 USA. [Fu, Shenglei] Henan Univ, Sch Environm & Planning, Kaifeng 475004, Peoples R China. RP Wu, PF (通讯作者)，Southwest Univ Nationalities, Coll Life Sci & Technol, Chengdu 610041, Peoples R China. EM wupf@swun.cn TC 27 Z9 35 PD APR 12 PY 2017 VL 7 AR 837 DI 10.1038/s41598-017-00805-5 UT WOS:000399186000001 DA 2023-03-23 ER PT J AU Zhang, Y Dong, SK Gao, QZ Liu, SL Ganjurjav, H Wang, XX Su, XK Wu, XY AF Zhang, Yong Dong, Shikui Gao, Qingzhu Liu, Shiliang Ganjurjav, Hasbagan Wang, Xuexia Su, Xukun Wu, Xiaoyu TI Soil bacterial and fungal diversity differently correlated with soil biochemistry in alpine grassland ecosystems in response to environmental changes SO SCIENTIFIC REPORTS DT Article AB To understand effects of soil microbes on soil biochemistry in alpine grassland ecosystems under environmental changes, we explored relationships between soil microbial diversity and soil total nitrogen, organic carbon, available nitrogen and phosphorus, soil microbial biomass and soil enzyme activities in alpine meadow, alpine steppe and cultivated grassland on the Qinghai-Tibetan plateau under three-year warming, enhanced precipitation and yak overgrazing. Soil total nitrogen, organic carbon and NH4-N were little affected by overgrazing, warming or enhanced precipitation in three types of alpine grasslands. Soil microbial biomass carbon and phosphorus along with the sucrase and phosphatase activities were generally stable under different treatments. Soil NO3-N, available phosphorus, urease activity and microbial biomass nitrogen were increased by overgrazing in the cultivated grassland. Soil bacterial diversity was positively correlated with, while soil fungal diversity negatively with soil microbial biomass and enzyme activities. Soil bacterial diversity was negatively correlated with, while soil fungal diversity positively with soil available nutrients. Our findings indicated soil bacteria and fungi played different roles in affecting soil nutrients and microbiological activities that might provide an important implication to understand why soil biochemistry was generally stable under environmental changes in alpine grassland ecosystems. C1 [Zhang, Yong; Dong, Shikui; Liu, Shiliang; Su, Xukun; Wu, Xiaoyu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Zhang, Yong] Southwest Forestry Univ, Natl Plateau Wetland Res Ctr, Kunming 650224, Peoples R China. [Gao, Qingzhu; Ganjurjav, Hasbagan; Wang, Xuexia] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China.; Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM dongshikui@sina.com; gaoqzh@ami.ac.cn TC 92 Z9 104 PD MAR 6 PY 2017 VL 7 BP 1 EP 10 AR 43077 DI 10.1038/srep43077 UT WOS:000395392900001 DA 2023-03-23 ER PT J AU Wang, YB Sun, Y Niu, FJ Wu, QB AF Wang, Yibo Sun, Yan Niu, Fujun Wu, Qingbai TI Using Cs-137 measurements to investigate the impact of soil erosion on soil nutrients in alpine meadows within the Yangtze River region, China SO COLD REGIONS SCIENCE AND TECHNOLOGY DT Article AB In this study, the Cs-137 technique was used to study soil erosion and its impact on soil nutrients in an alpine meadow area of the upper Yangtze River. The results show that soil erosion significantly affects the redistribution of soil organic carbon (SOC), total nitrogen (N) and total phosphorus (P). To characterize the distribution and dynamics of Cs-137, SOC, total N and total P in the intensively eroded soil, the SOC, total N, total P stocks and Cs-137 were measured in a reference plot derived from values extracted at Beiluhe Basin. More than 90% of Cs-137 were concentrated in the upper 0-10 cm of the soil profile within the reference plot, presenting an exponentially decreasing distribution with depth along the whole profile (R-2 > 0.8). Soil nutrient content and distribution changed noticeably after the soil eroded. The top 0-5 cm of the soil profile lost 65%, 70%, 67% and 12% of Cs-137, total N, SOC and total P respectively. Cs-137 increased from 58% to 70% at depths of 10-20 cm and 20-30 cm, whereas total N and SOC values decreased from 77% to 25%. During the process of erosion, there is a close relation between (CS)-C-137 changes and SOC, total N and total P values. (C) 2016 Elsevier B.V. All rights reserved. C1 [Wang, Yibo; Sun, Yan] Lanzhou Univ, Key Lab Western Chinas Environm Syst, Minist Educ, Coll Earth & Environm Sci, Lanzhou 730000, Peoples R China. [Wang, Yibo; Niu, Fujun; Wu, Qingbai] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Wang, YB (通讯作者)，Lanzhou Univ, Key Lab Western Chinas Environm Syst, Minist Educ, Coll Earth & Environm Sci, Lanzhou 730000, Peoples R China.; Wang, YB (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. EM wangyib@lzu.edu.cn TC 12 Z9 12 PD MAR PY 2017 VL 135 BP 28 EP 33 DI 10.1016/j.coldregions.2016.12.008 UT WOS:000393724200004 DA 2023-03-23 ER PT J AU Yin, GA Niu, FJ Lin, ZJ Luo, J Liu, MH AF Yin, Guoan Niu, Fujun Lin, Zhanju Luo, Jing Liu, Minghao TI Effects of local factors and climate on permafrost conditions and distribution in Beiluhe basin, Qinghai-Tibet Plateau, China SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Beiluhe basin is underlain by warm and ice-rich permafrost, and covered by vegetation and soils characteristic of the Qinghai-Tibet Plateau. A field monitoring network was established to investigate permafrost conditions and to assess potential impacts of local factors and climate change. This paper describes the spatial variations in permafrost conditions from instrumented boreholes, controlling environmental factors, and recent thermal evolution of permafrost in the basin. The study area was divided into 10 ecotypes using satellite imagery based classification. The field investigations and cluster analysis of ground temperatures indicated that permafrost underlies most of the ground in swamp meadow, undisturbed alpine meadow, degrading alpine meadow, and desert alpine grassland, but is absent in other cover types. Permafrost-ecotope relations examined over a 2-year (2014-2016) period indicated that: (i) ground surface temperatures varied largely among ecotopes; (ii) annual mean ground temperatures ranged from 1.5 to 0 degrees C in permafrost, indicating sensitive permafrost conditions; (iii) active-layer thicknesses ranged from 1.4 m to 3.4 m; (iv) ground ice content at the top of permafrost is high, but the active-layer soil is relatively dry. Long-term climate warming has driven thermal changes to permafrost, but ground surface characteristics and soil moisture content strongly influence the ground thermal state. These factors control local-scale spatial variations in permafrost conditions. The warm permafrost in the basin is commonly in thermal disequilibrium, and is sensitive to future climate change. Active-layer thicknesses have increased by at least 42 cm and the mean annual ground temperatures have increased by up to 0.2 degrees C in the past 10 years over the basin. A permafrost distribution map was produced based on ecotypes, suggesting that permafrost underlies 64% of the study region. C1 [Yin, Guoan; Niu, Fujun; Lin, Zhanju; Luo, Jing; Liu, Minghao] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soils Engn, Lanzhou 730000, Peoples R China. [Yin, Guoan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Niu, FJ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, State Key Lab Frozen Soils Engn, Lanzhou 730000, Peoples R China. EM niufujun@lzb.ac.cn TC 56 Z9 57 PD MAR 1 PY 2017 VL 581 BP 472 EP 485 DI 10.1016/j.scitotenv2016.12.155 UT WOS:000394635300044 DA 2023-03-23 ER PT J AU Zhang, ZQ Wu, QB Gao, SR Hou, YD AF Zhang, Zhongqiong Wu, Qingbai Gao, Siru Hou, Yandong TI Response of the soil hydrothermal process to difference underlying conditions in the Beiluhe permafrost region SO ENVIRONMENTAL EARTH SCIENCES DT Article AB The changes in hydrothermal dynamics under different underlying conditions are the important aspect of hydrological and ecological processes, and engineering stability in permafrost regions. This study monitored the temperature and moisture of soil at a depth range from 0 to 80 cm beneath the barren, alpine steppe, and alpine meadow at the Beiluhe Basin on the Qinghai-Tibet Plateau. The freezing and thawing process and hydrothermal dynamic changes were analyzed within the test range. In a year, the freezing and thawing process controlled the pattern of hydrothermal changes. The properties of ground surface affected the hydrothermal change process in various stages. In the freeze stages, moisture and the absolute value of ground temperature showed an exponential relationship. In the thawing stages, moisture may increase, decrease, or remain stable in different temperature ranges. This process is affected by precipitation, solar radiation, and so on. At a 0-30 cm depth range, moisture increased linearly with precipitation. At 0-20 cm depth range, precipitation had a significant effect on the ground temperature changes. With the same rainfall condition, the decline of ground temperature corresponds with solar radiation flux. Results confirmed that ground properties were important factors that control the soil moisture and temperature change in the permafrost region. C1 [Zhang, Zhongqiong; Wu, Qingbai; Gao, Siru; Hou, Yandong] Chinese Acad Sci, State Key Lab Frozen Soil Engn, NW Inst Eco Environm & Resources, Lanzhou 730000, Peoples R China. [Zhang, Zhongqiong; Wu, Qingbai] Chinese Acad Sci, Beiluhe Observat Stn Frozen Soil Environm & Engn, NW Inst Eco Environm & Resources, Golmud 816000, Qinghai, Peoples R China. RP Zhang, ZQ (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, NW Inst Eco Environm & Resources, Lanzhou 730000, Peoples R China. EM zhongqionghao@163.com TC 13 Z9 16 PD MAR PY 2017 VL 76 IS 5 AR 194 DI 10.1007/s12665-017-6518-8 UT WOS:000396208400007 DA 2023-03-23 ER PT J AU Li, W Epstein, HE Wen, ZM Zhao, JE Jin, JW Jing, GH Cheng, JM Du, GZ AF Li, Wei Epstein, Howard E. Wen, Zhongming Zhao, Jie Jin, Jingwei Jing, Guanghua Cheng, Jimin Du, Guozhen TI Community-weighted mean traits but not functional diversity determine the changes in soil properties during wetland drying on the Tibetan Plateau SO SOLID EARTH DT Article AB Climate change and human activities have caused a shift in vegetation composition and soil biogeochemical cycles of alpine wetlands on the Tibetan Plateau. The primary goal of this study was to test for associations between community-weighted mean (CWM) traits, functional diversity, and soil properties during wetland drying. We collected soil samples and investigated the aboveground vegetation in swamp, swamp meadow, and typical meadow environments. Four CWM trait values (specific leaf area is SLA, leaf dry matter content is LDMC, leaf area is LA, and mature plant height is MPH) for 42 common species were measured across the three habitats; three components of functional diversity (functional richness, functional evenness, and functional divergence) were also quantified at these sites. Our results showed that the drying of the wetland dramatically altered plant community and soil properties. There was a significant correlation between CWM of traits and soil properties, but not a significant correlation between functional diversity and soil properties. Our results further showed that CWM-LA, CWM-SLA, and CWM-LDMC had positive correlations with soil readily available nutrients (available nitrogen, AN; available phosphorus, AP), but negative correlations with total soil nutrients (soil organic carbon is SOC, total nitrogen is TN, and total phosphorus is TP). Our study demonstrated that simple, quantitative plant functional traits, but not functional diversity, are directly related to soil C and N properties, and they likely play an important role in plant-soil interactions. Our results also suggest that functional identity of species may be more important than functional diversity in influencing ecosystem processes during wetland drying. C1 [Li, Wei; Wen, Zhongming; Jin, Jingwei; Cheng, Jimin] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China. [Li, Wei; Wen, Zhongming; Jin, Jingwei; Jing, Guanghua; Cheng, Jimin] Chinese Acad Sci, Inst Soil & Water Conservat, Yangling 712100, Peoples R China. [Li, Wei; Wen, Zhongming; Jin, Jingwei; Jing, Guanghua; Cheng, Jimin] Minist Water Resource, Yangling 712100, Peoples R China. [Epstein, Howard E.] Univ Virginia, Dept Environm Sci, 291 McCormick Rd, Charlottesville, VA 22904 USA. [Zhao, Jie] Northwest A&F Univ, Coll Anim Sci & Technol, Yangling 712100, Peoples R China. [Du, Guozhen] Lanzhou Univ, Sch Life Sci, Lanzhou 730000, Peoples R China. RP Li, W (通讯作者)，Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China.; Li, W (通讯作者)，Chinese Acad Sci, Inst Soil & Water Conservat, Yangling 712100, Peoples R China.; Li, W (通讯作者)，Minist Water Resource, Yangling 712100, Peoples R China. EM liwei2013@nwsuaf.edu.cn TC 15 Z9 16 PD FEB 6 PY 2017 VL 8 IS 1 BP 137 EP 147 DI 10.5194/se-8-137-2017 UT WOS:000395084500002 DA 2023-03-23 ER PT J AU Bosch, A Schmidt, K He, JS Doerfer, C Scholten, T AF Bosch, Anna Schmidt, Karsten He, Jin-Sheng Doerfer, Corina Scholten, Thomas TI Potential CO2 emissions from defrosting permafrost soils of the Qinghai-Tibet Plateau under different scenarios of climate change in 2050 and 2070 SO CATENA DT Article AB Permafrost soils store enormous quantities of organic carbon. Especially on the alpine Qinghai-Tibet Plateau, global warming induces strong permafrost thawing, which strengthens the microbial decomposition of organic carbon and the emission of the greenhouse gas carbon dioxide (CO2). Enhanced respiration rates may intensify climate warming in turn, but the magnitude of future CO2 emissions from this data-scarce region in a changing climate remains highly uncertain. Here, we aim at an area-wide estimation of future potential CO2 emissions for the permafrost region on the Qinghai-Tibet Plateau as key region for climate change studies due to its size and sensitiveness. We calculated four potential soil respiration scenarios for 2050 and 2070 each. Using a regression model, results from laboratory experiments and C stock estimations from other studies, we provide an approximation of total potential soil CO2 emissions on a regional scale ranging from 737.90 g CO2 m(-2) 4224.77 g CO2 m(-2) y(-1). Our calculations as first estimate of thawing-induced CO2 emissions (5123 g CO2 m(-2) y(-1)-3002.82 g CO2 m(2) y(-1)) from permafrost soils of the Qinghai-Tibet Plateau under global warming appear to be consistent to measurements of C loss from thawing permafrost soils measured within other studies. Thawing-induced soil CO2 emissions from permafrost soils with a organic C content ranging from 2.42 g degrees C kg(-1) to 425.23 g C kg(-1) increase general soil respiration by at least about one third on average at a temperature of 5 degrees C. Differences between scenarios remain <1% and thawing-induced CO2 emissions generally decrease over time comparing 2015, 2050 and 2070. With this spatial approximation at a regional scale, a first area-wide estimate of potential CO2 emissions for 2050 and 2070 from permafrost soils of the Qinghai-Tibet Plateau is provided. This offers support of assessing potential area-specific greenhouse gas emissions and more differentiated climate change models. (C) 2016 Elsevier B.V. All rights reserved. C1 [Bosch, Anna; Schmidt, Karsten; Doerfer, Corina; Scholten, Thomas] Univ Tubingen, Dept Geosci, Chair Soil Sci & Geomorphol, Tubingen, Germany. [He, Jin-Sheng] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [He, Jin-Sheng] Peking Univ, Key Lab Earth Surface Proc, Coll Urban & Environm Sci, Dept Ecol,Minist Educ, Beijing 100871, Peoples R China. RP Bosch, A (通讯作者)，Univ Tubingen, Dept Geosci Soil Sci & Geomorphol, Ruemelinstr 19-23, D-72070 Tubingen, Germany. EM anna.bosch@geographie.uni-tuebingen.de TC 28 Z9 30 PD FEB PY 2017 VL 149 BP 221 EP 231 DI 10.1016/j.catena.2016.08.035 PN 1 UT WOS:000390733300021 DA 2023-03-23 ER PT J AU Feng, YF Wu, JS Zhang, J Zhang, XZ Song, CQ AF Feng, Yunfei Wu, Jianshuang Zhang, Jing Zhang, Xianzhou Song, Chunqiao TI Identifying the Relative Contributions of Climate and Grazing to Both Direction and Magnitude of Alpine Grassland Productivity Dynamics from 1993 to 2011 on the Northern Tibetan Plateau SO REMOTE SENSING DT Article AB Alpine grasslands on the Tibetan Plateau are claimed to be sensitive and vulnerable to climate change and human disturbance. The mechanism, direction and magnitude of climatic and anthropogenic influences on net primary productivity (NPP) of various alpine pastures remain under debate. Here, we simulated the potential productivity (with only climate variables being considered as drivers; NPPP) and actual productivity (based on remote sensing dataset including both climate and anthropogenic drivers; NPPA) from 1993 to 2011. We denoted the difference between NPPP and NPPA as NPPpc to quantify how much forage can be potentially consumed by livestock. The actually consumed productivity (NPPac) by livestock were estimated based on meat production and daily forage consumption per standardized sheep unit. We hypothesized that the gap between NPPpc and NPPac (NPPgap) indicates the direction of vegetation dynamics, restoration or degradation. Our results show that growing season precipitation rather than temperature significantly relates with NPPgap, although warming was significant for the entire study region while precipitation only significantly increased in the northeastern places. On the Northern Tibetan Plateau, 69.05% of available alpine pastures showed a restoration trend with positive NPPgap, and for 58.74% of alpine pastures, stocking rate is suggested to increase in the future because of the positive mean NPPgap and its increasing trend. This study provides a potential framework for regionally regulating grazing management with aims to restore the degraded pastures and sustainable management of the healthy pastures on the Tibetan Plateau. C1 [Feng, Yunfei; Wu, Jianshuang; Zhang, Xianzhou] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Wu, Jianshuang] Free Univ Berlin, Dahlem Ctr Plant Sci, Biodivers Ecol Modelling, D-14195 Berlin, Germany. [Zhang, Jing] Beijing Normal Univ, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China. [Song, Chunqiao] Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90095 USA. RP Wu, JS (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China.; Wu, JS (通讯作者)，Free Univ Berlin, Dahlem Ctr Plant Sci, Biodivers Ecol Modelling, D-14195 Berlin, Germany. EM fengyf.13b@igsnrr.ac.cn; wujs07s@zedat.fu-berlin.de; jingzhang@bnu.edu.cn; zhangxz@igsnrr.ac.cn; chunqiao@ucla.edu TC 19 Z9 20 PD FEB PY 2017 VL 9 IS 2 AR 136 DI 10.3390/rs9020136 UT WOS:000397013700038 DA 2023-03-23 ER PT J AU Cong, N Shen, MG Piao, SL Chen, XQ An, S Yang, W Fu, YSH Meng, FD Wang, T AF Cong, Nan Shen, Miaogen Piao, Shilong Chen, Xiaoqiu An, Shuai Yang, Wei Fu, Yongshuo H. Meng, Fandong Wang, Tao TI Little change in heat requirement for vegetation green-up on the Tibetan Plateau over the warming period of 1998-2012 SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB We investigated spatial and temporal variations in the accumulated growing degree-days (AGDD) requirement for spring vegetation green-up onset on the Tibetan Plateau (TP) during the rapid warming period of 1998-2012, which is essential for understanding and modeling the spring vegetation phenological responses to climate change. Annual green-up date was determined by using a satellite-derived normalized difference vegetation index. The annual AGDD requirement was then determined as the sum of daily mean air temperatures above 0 degrees C over the dormancy period. Linear regression between the AGDD requirement and year was used to determine its temporal trend. Partial correlation analysis was used to assess factors controlling inter-annual variations in the AGDD requirement. We found the AGDD requirement was significantly different for different vegetation types and showed large spatial variations ranging from a few degrees C-days in cold and wet areas to more than 1000 degrees C-days in warm and dry areas of the TP. Despite the rapid warming and subsequent earlier green-up date, the AGDD requirement did not increase significantly over the period 1998-2012. Interestingly, we found that the inter-annual variations in AGDD requirement were extensively driven by the number of chilling days, while precipitation sum and insolation affected the AGDD requirement in limited areas. Although the winter warming reduced chilling accumulation on the TP, the AGDD requirement for vegetation green-up onset did not necessarily increase over 1998-2012, being insensitive to decline in the chilling accumulation. This suggested that the chilling requirement to break vegetation dormancy might be still fulfilled. In other words, the winter warming might not substantially affect the vegetation green-up process, since the reduction in chilling accumulation may not affect the dormancy break. However, the negative temporal correlation between the AGDD requirement and number of chilling days indicates that continued future warming may lead to a deficiency in chilling and thus an increase in AGDD requirement. (C) 2016 Elsevier B.V. All rights reserved. C1 [Cong, Nan; Shen, Miaogen; Piao, Shilong; Meng, Fandong; Wang, Tao] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, 16 Lincui Rd, Beijing 100101, Peoples R China. [Shen, Miaogen; Piao, Shilong; Wang, Tao] CAS Ctr Excellence Tibetan Plateau Earth Sci, 16 Lincui Rd, Beijing 100101, Peoples R China. [Piao, Shilong; Chen, Xiaoqiu; An, Shuai; Fu, Yongshuo H.] Peking Univ, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. [Yang, Wei] Chiba Univ, Ctr Environm Remote Sensing, Chiba 2638522, Japan. [Fu, Yongshuo H.] Univ Antwerp, Dept Biol, Ctr Excellence PLECO Plant & Vegetat Ecol, Univ Pl 1, B-2610 Antwerp, Belgium. RP Shen, MG (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, 16 Lincui Rd, Beijing 100101, Peoples R China. EM shen.miaogen@gmail.com TC 40 Z9 44 PD JAN 15 PY 2017 VL 232 BP 650 EP 658 DI 10.1016/j.agrformet.2016.10.021 UT WOS:000389089800053 DA 2023-03-23 ER PT J AU You, QG Xue, X Peng, F Dong, SY Gao, YH AF You, Quangang Xue, Xian Peng, Fei Dong, Siyang Gao, Yanhong TI Surface water and heat exchange comparison between alpine meadow and bare land in a permafrost region of the Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Patch degradation of the alpine meadow on the Tibetan Plateau (TP) induced by climate warming and anthropogenic activities affects the pattern of coupled water and heat cycling between the land surface and the atmosphere, which could positively feedback to the regional and global climate warming. However, previous research has mostly focused on the homogeneous underlying surface rather than heterogeneous underlying surface. Thus, this study aims at forming a better understanding of the difference in water and heat exchange over heterogeneous underlying surface in the permafrost region of the TP hinterland. We based our analysis on two years of weather and energy flux measurements that were collected over two contrasting landscapes under the same climate conditions: a natural alpine meadow (AM) and severely degraded alpine meadow, termed bare land (BL). The major surface characteristics affecting the difference between AM and BL energy budgets are also presented and analyzed (such as land surface albedo and temperature, shallow soil temperature and moisture, soil stratification, and phenology). The results show that the thawing of a shallow active soil layer induced a rapid increase in soil moisture, triggering the dramatic change in main energy partitioning from sensible heat flux (H) to latent heat flux (LE) in both AM and BL sites. Surface albedo decreased but surface cooling increased with the reduction in the vegetation coverage, and temperature gradient between surface and 10 cm depth increased with the erosion of root turf that is capable of thermal insulation and high water retention, together could alter the surface energy budget. The annual surface heat source or available energy (R-n-G) in AM was approximately equal to that in BL. However, more available energy was consumed by H to warm the low atmosphere in BL as evidenced by the Bowen ratio increasing from 0.49 to 0.84 in summer and from 2.96 to 5.64 over a whole year. The results of this research suggest that the soil moisture, canopy, and root turf were the major factors affecting the energy partitioning in the hinterland of the TP. The decrease in vegetation coverage results in increases of H and heating of the lower atmosphere. Therefore, this could lead to a potential positive feedback to regional climate warming. In addition, given the background of TP warming, Kobresia turf can effectively prevent permafrost degradation due to its thermal insulation characteristics. (C) 2016 Elsevier B.V. All rights reserved. C1 [You, Quangang; Xue, Xian; Peng, Fei; Dong, Siyang] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Key Lab Desert & Desertificat, 320 West Donggang Rd, Lanzhou 730000, Peoples R China. [You, Quangang; Gao, Yanhong] Chinese Acad Sci, Key Lab Land Surface Proc & Climate Change Cold &, Lanzhou 730000, Peoples R China. [Dong, Siyang] Univ Chinese Acad Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China. RP Xue, X (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Key Lab Desert & Desertificat, 320 West Donggang Rd, Lanzhou 730000, Peoples R China. EM xianxue@lzb.ac.cn TC 54 Z9 65 PD JAN 15 PY 2017 VL 232 BP 48 EP 65 DI 10.1016/j.agrformet.2016.08.004 UT WOS:000389089800005 DA 2023-03-23 ER PT J AU Dong, YQ Sun, ZJ An, SH Yang, HL Yang, J Ma, L AF Dong, Yiqiang Sun, Zongjiu An, Shazhou Yang, Helong Yang, Jing Ma, Liang TI NATURAL RESTORATION OF DEGRADED GRASSLAND ON THE NORTHERN XINJIANG, CHINA: THE RESTORATION DIFFERENCE BETWEEN LIGHTLY AND MODERATELY DEGRADED DESERTS UNDER GRAZING EXCLUSION SO FRESENIUS ENVIRONMENTAL BULLETIN DT Article AB Overgrazing has caused extensively vegetation destruction in deserts, the widely distributed type of grassland in northern Xinjiang, China. To restore the degraded desert ecosystems, grazing exclusion (GE) was extensively implemented in recent decades. However, changes in the vegetation characteristics and plant biodiversity in different years of GE have not been thoroughly elucidated. This study paper examines the changes in desert community characteristics (i.e., biomass, coverage, density) and plant biodiversity (i.e. Margelef richness index, Simpson dominance index and Pielou evenness index) under lightly degraded desert (LD) in Urumqi with freely grazing (FG), 1 a, 6 a,9 a and moderately degraded desert (MD) in Shawan with FG, 1 a, 4 a, 11 a. The results indicated that the vegetation density and biomass in LD had no statistical difference response to GE, while compared with FG, the coverage and biomass of GE sites in MD sigiiificantly increased by 36.9%-115.7% and 62.9%-217.5%, respectively. Relative short-term GE could increase Simpson dominance index and Margelef richness index in LD, but the Simpson dominance index and Pielou evenness index reduced in relative long-term GE condition. In addition, we suggests that the optimal vegetation biomass and plants growth condition of LD and MD were calculated and observed at the 4-5 a and 7-11 a in our study areas, respectively. Hence, we proposed that degraded deserts should adopt the grazing management when it recovered to a certain extent. C1 [Dong, Yiqiang; Sun, Zongjiu; An, Shazhou; Yang, Helong; Yang, Jing; Ma, Liang] Xinjiang Agr Univ, Coll Pratacultural & Environm Sci, Nongda East Rd 311, Urumqi 830052, Xinjiang, Peoples R China. [Dong, Yiqiang; Sun, Zongjiu; An, Shazhou; Yang, Helong; Yang, Jing] Key Lab Grassland Resources & Ecol Xinjiang, Urumqi 830052, Xinjiang, Peoples R China. RP An, SH (通讯作者)，Xinjiang Agr Univ, Coll Pratacultural & Environm Sci, Nongda East Rd 311, Urumqi 830052, Xinjiang, Peoples R China. EM xjasz@126.com TC 6 Z9 8 PY 2017 VL 26 IS 6 BP 3845 EP 3855 UT WOS:000405360700017 DA 2023-03-23 ER PT J AU Gao, ZY Niu, FJ Wang, YB Luo, J Lin, ZJ AF Gao, Zeyong Niu, Fujun Wang, Yibo Luo, Jing Lin, Zhanju TI Impact of a thermokarst lake on the soil hydrological properties in permafrost regions of the Qinghai-Tibet Plateau, China SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The formation of thermokarst lakes can degrade alpine meadow ecosystems through changes in soil water and heat properties, which might have an effect on the regional surface water and groundwater processes. In this study, a typical thermokarst lake was selected in the Qinghai-Tibet Plateau (QTP), and the ecological index (S-L) was used to divide the affected areas into extremely affected, severely affected, medium-affected, lightly affected, and non-affected areas, and soil hydrological properties, including saturated hydraulic conductivity and soil water-holding capacity, were investigated. The results showed that the formation of a thermokarst lake can lead to the degradation of alpine meadows, accompanied by a change in the soil physiochemical and hydrological properties. Specifically, the soil structure turned towards loose soil and the soil nutrients decreased from non-affected areas to severely affected areas, but the soil organic matter and available potassium increased slightly in the extremely affected areas. Soil saturated hydraulic conductivity showed a 1.7- to 4.1-fold increase in the lake-surrounding areas, and the highest value (401.9 cm d(-1)) was detected in the severely affected area. Soil water-holding capacity decreased gradually during the transition from the non-affected areas to the severely affected areas, but it increased slightly in the extremely affected areas. The principal component analysis showed that the plant biomass was vital to the changes in soil hydrological properties. Thus, the vegetation might serve as a link between the thermokarst lake and soil hydrological properties. In this particular case, it was concluded that the thermokarst lake adversely affected the regional hydrological services in the alpine ecosystem. These results would be useful for describing appropriate hydraulic parameters with the purpose of modeling soil water transportation more accurately in the Qinghai-Tibet Plateau. (C) 2016 Elsevier B.V. All rights reserved. C1 [Gao, Zeyong; Niu, Fujun; Luo, Jing; Lin, Zhanju] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. [Gao, Zeyong] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Gao, Zeyong; Wang, Yibo] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Peoples R China. RP Niu, FJ (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. EM niufujun@lzb.ac.cn TC 21 Z9 23 PD JAN 1 PY 2017 VL 574 BP 751 EP 759 DI 10.1016/j.scitotenv.2016.09.108 UT WOS:000389090100072 DA 2023-03-23 ER PT J AU Li, W Cao, WX Wang, JL Li, XL Xu, CL Shi, SL AF Li, Wen Cao, Wenxia Wang, Jinlan Li, Xiaolong Xu, Changlin Shi, Shangli TI Effects of grazing regime on vegetation structure, productivity, soil quality, carbon and nitrogen storage of alpine meadow on the Qinghai-Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB Grazing regime has an important effect on grassland ecosystem. however, the mechanisms how alpine meadow vegetation, soil quality responds to this management regime remain unclear. A short term field experiment (4-5 years) was conducted to quantify the impact of different grazing management regimes (fencing (NG), grazing rest in growing stage (RG), traditional grazing (TG) and continued grazing (CG)) on alpine meadow of the Qinghai-Tibet Plateau (QTP) and investigated vegetation structure, soil physicochemical properties, C and N storage regarding grazing regime, during two consecutive years: 2014 and 2015. Our results revealed that the above-, below-ground and litter biomass, plant coverage in NG were significantly higher than those in RG, TG and CG in 2014 and 2015. The NG significantly increased the diversity, evenness and richness indexes when compared to CG, while NG significantly decreased those indexes compared with RG. Meanwhile, litter biomass and plant coverage had no significant difference between RG and TG in 2014 and 2015, and the above- and below-ground biomass had no significant difference between RG and TG in 2014, but RG significantly increased the above- and below-ground biomass compared with TG in 2015. The NG, RG and TG sites all significantly improved the bulk density, soil compaction in 0-30 cm soil depth, available nitrogen and available potassium concentrations in 0-10 cm soil layer compared with CG site. NG, RG and TG all significantly increased the soil water content, total nitrogen, total phosphorus and available phosphorus in 0-30 cm soil depth compared with CG site. The C and N storage in vegetation, 0-40 cm soil depth and whole ecosystem were significantly increased in NG, RG and TG compared with CG in both years. Our results demonstrated that fencing is the most suitable grazing management regime on alpine meadow of the QTP. However, taking into account other factors such as: use and update of grassland resources, economic income stability of herdsmen, the grazing rest in the growing stage enable to promote the efficient use of grassland resources, maintaining alpine ecosystem and preventing it from further degradation or desertification is the best one. (C) 2016 Elsevier B.V. All rights reserved. C1 [Li, Wen; Cao, Wenxia; Li, Xiaolong; Xu, Changlin; Shi, Shangli] Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Grassland Sci Coll, Grassland Ecosyst Key Lab,Minist Educ, Lanzhou 730030, Peoples R China. [Wang, Jinlan] Gansu Agr Univ, Coll Anim Sci & Technol, Lanzhou 730030, Peoples R China. RP Cao, WX (通讯作者)，Gansu Agr Univ, Sino US Res Ctr Sustainable Grassland & Livestock, Grassland Sci Coll, Grassland Ecosyst Key Lab,Minist Educ, Lanzhou 730030, Peoples R China. EM caowenxia@foxmail.com TC 76 Z9 88 PD JAN PY 2017 VL 98 BP 123 EP 133 DI 10.1016/j.ecoleng.2016.10.026 UT WOS:000390454300016 DA 2023-03-23 ER PT J AU Lu, XY Kelsey, KC Yan, Y Sun, J Wang, XD Cheng, GW Neff, JC AF Lu, Xuyang Kelsey, Kathy C. Yan, Yan Sun, Jian Wang, Xiaodan Cheng, Genwei Neff, Jason C. TI Effects of grazing on ecosystem structure and function of alpine grasslands in Qinghai-Tibetan Plateau: a synthesis SO ECOSPHERE DT Article AB Humans have grazed on the Qinghai-Tibetan Plateau (QTP) for many thousands of years. In recent decades, the intensity of grazing has increased and several new management strategies have been put into place to address the resulting changes in rangeland condition. Effective management of grazing activities in this region requires understanding the impact of livestock grazing across the diverse array of alpine grassland ecosystems present in the QTP, but recent studies have identified a number of critical uncertainties in the ecological science that underlies these management principles. To address these uncertainties, we carried out a synthesis analysis of the effect of livestock grazing on 26 indicators of ecosystem structure and function based on 61 studies from 88 independent research sites within the QTP. Our synthesis results indicate that livestock grazing exerts complex controls on ecosystem structure and function, which vary according to local landscape characteristics. We found that grazing contributes to greater plant species diversity (Shannon-Wiener index, Simpson dominance index, and Pielou evenness index significantly increased 0.18, 0.05, and 0.03, respectively, due to grazing), but decreased aboveground biomass (47.15%), soil organic carbon (12.41%), soil total nitrogen (12.75%), and microbial biomass carbon (9.42%). Further, ecosystem function is controlled by interactions between grazing and other landscape characteristics such as elevation and mean annual temperature. The management regime currently in place in the QTP, which involves complete exclusion of grazing in some areas, can have variable effects on grassland health. Therefore, the complexity of these responses is an indication that livestock and grassland management may benefit from a more nuanced management regime than is currently utilized in the QTP. C1 [Lu, Xuyang; Yan, Yan; Wang, Xiaodan; Cheng, Genwei] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Lu, Xuyang; Kelsey, Kathy C.; Neff, Jason C.] Univ Colorado, Environm Studies Program, Boulder, CO 80309 USA. [Sun, Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. RP Lu, XY (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China.; Lu, XY (通讯作者)，Univ Colorado, Environm Studies Program, Boulder, CO 80309 USA. EM xylu@imde.ac.cn TC 127 Z9 139 PD JAN PY 2017 VL 8 IS 1 AR e01656 DI 10.1002/ecs2.1656 UT WOS:000396526300005 DA 2023-03-23 ER PT C AU Niu, CS Li, BF Zhang, YA Sakamoto, M AF Niu, Chengshui Li, Bingfen Zhang, Yu-an Sakamoto, Makoto BE Sugisaka, M Jia, Y Ito, T Lee, JJ TI Application of ViSC to the Natural Grazing in Qinghai Tibet Plateau SO ICAROB 2017: PROCEEDINGS OF THE 2017 INTERNATIONAL CONFERENCE ON ARTIFICIAL LIFE AND ROBOTICS DT Proceedings Paper CT International Conference on Artificial Life and Robotics (ICAROB) CY JAN 19-22, 2017 CL Miyazaki, JAPAN AB "SanjiangyuanRegion" is a complex ecosystem with typical characteristics of alpine grass land, which the livestock production relies mainly on the yak grazing. In recent year, grassland degradation, the reduction of herdsmen income and on-going deterioration of the ecological environment caused by human disturbance are gradually intense, which a scientific and rational grazing mode of combination of ecological animal husbandry and sustainable utilization of grassland should be established urgently. Applying the ViSC combined with the optimization theory, will study establish the optimization of alpine grassland yak grazing system, which provides a theoretical basis for scientific grazing. C1 [Niu, Chengshui; Zhang, Yu-an] Qinghai Univ, Dept Comp Technol & Applicat, Xining 810016, Peoples R China. [Li, Bingfen] Qinghai Univ, Sch Mech Engn, Xining 810016, Peoples R China. [Sakamoto, Makoto] Univ Miyazaki, Fac Engn, Miyazaki 8892192, Japan. RP Zhang, YA (通讯作者)，Qinghai Univ, Dept Comp Technol & Applicat, Xining 810016, Peoples R China. EM 2011990029@qhu.edu.cn TC 0 Z9 0 PY 2017 BP P683 EP P687 UT WOS:000404239000160 DA 2023-03-23 ER PT J AU Shang, ZH Hou, Y Li, F Guo, CC Jia, TH Degen, AA White, A Ding, LM Long, RJ AF Shang, Zhanhuan Hou, Yuan Li, Fei Guo, Cancan Jia, Tianhua Degen, A. Allan White, Andrew Ding, Luming Long, Ruijun TI Inhibitory action of allelochemicals from Artemisia nanschanica to control Pedicularis kansuensis, an annual weed of alpine grasslands SO AUSTRALIAN JOURNAL OF BOTANY DT Article AB The inhibitory action of allelochemicals can be used effectively for biological weed management and can minimise environmental impacts related to herbicides. The aim of the present study was to identify allelochemicals of Artemisia nanschanica Krasch, a typical weed with strong allelopathic effects, that could potentially control Pedicularis kansuensis Maxim, the key pioneer weed that causes rapid degradation of alpine pastures. Gas chromatography and mass spectrometry were used to identify the compounds of six extracts from A. nanschanica. Two ethyl acetate extracts were the most effective in reducing the seed germination rate and in inhibiting seedling shoot and root growth of P. kansuensis. Three chemical compounds from the ethyl acetate extracts were identified for their allelopathic inhibitory effects, a sesquiterpene and two aromadendrene oxides, with the sesquiterpene being the most effective. The three compounds showed the best inhibitory effect through synergistic action. We concluded that the three allelochemicals of A. nanschanica, either alone or in combination, can be used to biologically control P. kansuensis in alpine pastures on the Tibetan plateau. C1 [Shang, Zhanhuan; Hou, Yuan; Li, Fei; Guo, Cancan; Jia, Tianhua; Ding, Luming; Long, Ruijun] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Sch Life Sci, Lanzhou 730000, Gansu, Peoples R China. [Degen, A. Allan] Ben Gurion Univ Negev, Desert Anim Adaptat & Husb, Wyler Dept Dryland Agr, Blaustein Inst Desert Res, IL-8410500 Beer Sheva, Israel. [White, Andrew] Univ Adelaide, Sch Earth & Environm Sci, Adelaide, SA 5005, Australia. RP Shang, ZH (通讯作者)，Lanzhou Univ, State Key Lab Grassland Agroecosyst, Sch Life Sci, Lanzhou 730000, Gansu, Peoples R China. EM shangzhh@lzu.edu.cn TC 4 Z9 5 PY 2017 VL 65 IS 4 BP 305 EP 314 DI 10.1071/BT17014 UT WOS:000406131200001 DA 2023-03-23 ER PT J AU Xu, HJ Wang, XP Zhang, XX AF Xu, Hao-jie Wang, Xin-ping Zhang, Xiao-xiao TI Impacts of climate change and human activities on the aboveground production in alpine grasslands: a case study of the source region of the Yellow River, China SO ARABIAN JOURNAL OF GEOSCIENCES DT Article AB Changes in aboveground net primary productivity (ANPP) in alpine grasslands are the consequence of climate change and human activities, but it is difficult to disentangle their relative contributions. Based on monthly remote-sensed vegetation index and meteorological data during the period 1982-2010, we analysed the long-term variation of annual ANPP in the source region of the Yellow River and quantified the effects of climate and human activities including grazing on ANPP variability, using the Carnegie-Ames-Stanford Approach (CASA) model and the ANPP-based residual trend analysis method. Our results suggested that ANPP increased in 80% of alpine grasslands. Areas with negative changes in ANPP were found mainly in the eastern portion of the region, accounting for 0.3% of alpine grasslands. ANPP was positively correlated with the monthly mean temperature from June to September and the sunshine duration in September at a regional scale. Moreover, ANPP was negatively correlated with the total livestock numbers. Using the residual trend analysis method, we demonstrated that climate and human activities accounted for 76.6 and 23.4%, respectively, of the variability in ANPP for the entire study region in 1982-2010. We concluded that climate change alleviated climatic constraints, in particular temperature limitations and sunshine duration, resulting in a significant increase in ANPP. Overgrazing was supposed to be the primary driver for grassland degradation in the eastern region. Our study has implications for grassland management and its sustainability to minimize the risk of grassland degradation and desertification processes in geoecologically and socially important regions such as the study region in China. C1 [Xu, Hao-jie; Wang, Xin-ping] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Shapotou Desert Res & Expt Stn, Lanzhou 730000, Peoples R China. [Xu, Hao-jie] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Xiao-xiao] Lanzhou Univ, Sch Phys Sci & Technol, Lanzhou 730000, Peoples R China. RP Xu, HJ (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Shapotou Desert Res & Expt Stn, Lanzhou 730000, Peoples R China.; Xu, HJ (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM xuhj2014@lzb.ac.cn TC 20 Z9 23 PD JAN PY 2017 VL 10 IS 1 AR 17 DI 10.1007/s12517-016-2801-3 UT WOS:000392059600017 DA 2023-03-23 ER PT J AU Yi, SH AF Yi, Shuhua TI FragMAP: a tool for long-term and cooperative monitoring and analysis of small-scale habitat fragmentation using an unmanned aerial vehicle SO INTERNATIONAL JOURNAL OF REMOTE SENSING DT Article; Proceedings Paper CT Conference on Small Unmanned Aerial Systems (sUAS) for Environmental Research CY JUN, 2016 CL Univ Worcester, Worcester, ENGLAND HO Univ Worcester AB Small patches of fragmented landscape cannot be resolved using remote-sensing satellite images and they are too numerous and too irregular to be measured easily and efficiently on the ground. As a result, studies of habitat fragmentation at small scales are inadequate. The major objective of this study is to develop a practical tool that can be used for the long-term and cooperative monitoring and analysis of small-scale habitat fragmentation with an unmanned aerial vehicle (UAV). This tool has two components. The software consists of: (1) field trip preparation; (2) auto-piloting; (3) image location and selection; and (4) image analysis. The hardware comprises: (1) a desktop computer; (2) a Phantom 3 Professional four-wheel drone (DJI Innovation Company Inc.); and (3) a Huawei Pad with an Android 4.4 operating system. This tool was demonstrated during field trips on the Qinghai-Tibetan Plateau (QTP) in the summer of 2015. It is stable, robust, efficient, and easy to operate. More importantly, it is designed to be used in a cooperative way within a team and among groups and for long-term repeated monitoring. This tool is suitable for widespread deployment to establish a monitoring network studying small-scale habitat fragmentation status and rate of change. C1 [Yi, Shuhua] Chinese Acad Sci, Arid Regions Environm & Engn Res Inst, State Key Lab Cryospher Sci Cold, Lanzhou, Peoples R China. [Yi, Shuhua] Nantong Univ, Sch Geog Sci, Nantong, Peoples R China. RP Yi, SH (通讯作者)，Chinese Acad Sci, Arid Regions Environm & Engn Res Inst, State Key Lab Cryospher Sci Cold, Lanzhou, Peoples R China.; Yi, SH (通讯作者)，Nantong Univ, Sch Geog Sci, Nantong, Peoples R China. EM yis@lzb.ac.cn TC 41 Z9 57 PY 2017 VL 38 IS 8-10 BP 2686 EP 2697 DI 10.1080/01431161.2016.1253898 UT WOS:000397995100037 DA 2023-03-23 ER PT J AU Yu, KF Lehmkuhl, F Falk, D AF Yu, Kai-Feng Lehmkuhl, Frank Falk, Dimitri TI Quantifying land degradation in the Zoige Basin, NE Tibetan Plateau using satellite remote sensing data SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Considerable efforts have been dedicated to desertification research in the arid and semi-arid drylands of central Asia. However, there are few quantitative studies in conjunction with proper qualitative evaluation concerning land degradation and aeolian activity in the alpine realm. In this study, spectral information from two Landsat-5 TM scenes (04.08.1994 and 28.07.2009, respectively) was combined with reference information obtained in the field to run supervised classifications of eight landscape types for both time steps. Subsequently, the temporal and spatial patterns of the alpine wetlands/grasslands evolutions in the Zoige Basin were quantified and assessed based on these two classification maps. The most conspicuous change is the sharp increase of similar to 627 km(2) degraded meadow. Concerning other land-covers, shallow wetland increases similar to 107 km(2) and aeolian sediments (mobile dunes and sand sheets) have an increase of similar to 30 km(2). Considering the deterioration, an obvious decrease of 440 km(2) degraded wetland can be observed. Likewise, decrease of deep wetland (similar to 78 km(2)), humid meadow (similar to 80 km(2)) and undisturbed meadow (similar to 88 km(2)) were determined. These entire evolution matrixes undoubtedly hint a deteriorating tendency of the Zoige Basin ecosystem, which is characterized by significantly declined proportion of intact wetlands, meadow, rangeland and a considerable increase of degraded meadow and larger areas of mobile dunes. In particular, not only temporal alteration of the land cover categories, the spatial and topographical characteristics of the land degradation also deserves more attention. In the alpine rangelands, the higher terraces of the river channels along with their slopes are more liable to the degradation and desertification. This tendency has significantly impeded the nomadic and agriculture activities. The set of anthropozoogenic factors encompassing enclosures, overgrazing and trampling, rodent damaging and exceedingly ditching in the wetlands are assumed to be the main controlling mechanisms for the landscape degradation. A suite of strict protection policies is urgent and indispensable for self-regulation and restoration of the alpine meadow ecosystem. Controlling the size of livestock, less ditching in the rangeland, and the launching of a more strict nature reserve management by adjacent Ruoergai, Maqu and Hongyuan Counties would be practical and efficacious in achieving these objectives. C1 [Yu, Kai-Feng; Lehmkuhl, Frank; Falk, Dimitri] Rhein Westfal TH Aachen, Dept Geog, Templergraben 55, D-52056 Aachen, Germany. RP Yu, KF (通讯作者)，Rhein Westfal TH Aachen, Dept Geog, Templergraben 55, D-52056 Aachen, Germany. EM kaifeng.yu@geo.rwth-aachen.de; flehmkuhl@geo.rwth-aachen.de; dimitri.falk@geo.rwth-aachen.de TC 22 Z9 27 PD JAN PY 2017 VL 14 IS 1 BP 77 EP 93 DI 10.1007/s11629-016-3929-z UT WOS:000394156500006 DA 2023-03-23 ER PT J AU Zhang, L Unteregelsbacher, S Hafner, S Xu, XL Schleuss, PM Miehe, G Kuzyakov, Y AF Zhang, Li Unteregelsbacher, Sebastian Hafner, Silke Xu, Xingliang Schleuss, Per-Marten Miehe, Georg Kuzyakov, Yakov TI Fate of Organic and Inorganic Nitrogen in Crusted and Non-Crusted Kobresia Grasslands SO LAND DEGRADATION & DEVELOPMENT DT Article AB A widespread pattern of the Tibetan plateau is mosaics of grasslands of Cyperaceae and grasses with forbs, interspersed with patches covered by lichen crusts induced by overgrazing. However, the fate of inorganic and organic N in non-crusted and crusted patches in Kobresia grasslands remains unknown. We reported on a field N-15-labeling experiment in two contrasting patches to compare retention of organic and inorganic N over a period of 29days. N-15 as KNO3, (NH4)(2)SO4 or glycine was sprayed onto soil surface. Crusted patches decreased plant and soil N stocks. More N-15 from three N forms was recovered in soil than plants in both patches 29days after the labeling. In non-crusted patches, N-15 recovery by the living roots was about two times higher than in crusted ones, mainly because of higher root biomass. Microorganisms in non-crusted patches were N-limited because of more living roots and competed strongly for N with roots. Inorganic N input to non-crusted patches could alleviate N limitation to plants and microorganisms, and leads to higher total N-15 recovery (plant+soil) for inorganic N forms. Compared to non-crusted patches, microorganisms in crusted patches were more C-limited because of depletion of available C caused by less root exudation. Added glycine could activate microorganisms, together with the hydrophobicity of glycine and crusts, leading to higher N-15-glycine than inorganic N. We conclude that overgrazing-induced crusts in Kobresia grasslands changed the fate of inorganic and organic N, and lead to lower total recovery from inorganic N but higher from organic N. Copyright (c) 2016 John Wiley & Sons, Ltd. C1 [Zhang, Li; Xu, Xingliang; Kuzyakov, Yakov] Chinese Acad Sci, Inst Geog Sci & Nat Resources, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China. [Zhang, Li; Unteregelsbacher, Sebastian; Hafner, Silke; Schleuss, Per-Marten; Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, Gottingen, Germany. [Zhang, Li] Univ Chinese Acad Sci, Beijing, Peoples R China. [Miehe, Georg] Univ Marburg, Fac Geog, Marburg, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan, Russia. RP Xu, XL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources, Key Lab Ecosyst Network Observat & Modeling, Beijing, Peoples R China. EM xuxingl@hotmail.com TC 26 Z9 26 PD JAN PY 2017 VL 28 IS 1 BP 166 EP 174 DI 10.1002/ldr.2582 UT WOS:000393800400015 DA 2023-03-23 ER PT J AU Zong, N Shi, PL Chai, X Jiang, J Zhang, XZ Song, MH AF Zong, Ning Shi, Pei-li Chai, Xi Jiang, Jing Zhang, Xian-zhou Song, Ming-hua TI Responses of ecosystem respiration to nitrogen enrichment and clipping mediated by soil acidification in an alpine meadow SO PEDOBIOLOGIA DT Article AB Clipping is one of the most important land-use practices in grassland ecosystems, yet the extent of clipping effect on ecosystem carbon (C) cycles depends on its interaction with nitrogen (N) deposition in future global climate change scenario, especially in the N-limited alpine meadow ecosystem. We conducted a field N addition (40 kg N ha(-1) yr(-1)) and clipping experiment in an alpine meadow on the northern Tibet Plateau to investigate the effects of exogenous N input and clipping on ecosystem (Re) and soil respiration (Rs). Generally, N enrichment enhanced Re, Rs and aboveground biomass (AGB) in the second year of the experiment, but the extent of the enhancements decreased from the third year of the experiment. Clipping didn't affect Re, Rs and AGB relative to the control, while clipping and N addition significantly increased belowground biomass. Soil inorganic N increased, while soil pH decreased with the year of N additions. Significant positive correlations of aboveground biomass with Re and Rs suggest the increase of plant photosynthetic C fixation under N addition is a key force in driving thus ecosystem CO2 efflux. However, the positive correlation between soil pH and aboveground biomass indicated soil acidification could be one of important factors decelerating the positive responses of plant growth to soil N availability increase. All the results suggest soil acidification due to N addition influenced the effects of N enrichment and clipping on ecosystem CO2 efflux through modulating plant growth and photosynthetic C allocation. (C) 2016 Elsevier GmbH. All rights reserved. C1 [Zong, Ning; Shi, Pei-li; Chai, Xi; Zhang, Xian-zhou; Song, Ming-hua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, A11,Datun Rd, Beijing 100101, Peoples R China. [Chai, Xi] Univ Chinese Acad Sci, 19 Yuquan Rd, Beijing 100049, Peoples R China. [Jiang, Jing] Nanjing Agr Inst Jiangsu Hilly Reg, 6 Xianyin South Rd, Nanjing 210046, Jiangsu, Peoples R China. [Shi, Pei-li] Univ Chinese Acad Sci, Coll Resources & Environm, 19 Yuquan Rd, Beijing 100049, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Lhasa Natl Ecol Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM shipl@igsnrr.ac.cn TC 13 Z9 14 PY 2017 VL 60 BP 1 EP 10 DI 10.1016/j.pedobi.2016.11.001 UT WOS:000394067600001 DA 2023-03-23 ER PT J AU Wang, HM Sun, J Li, WP Wu, JB Chen, YJ Liu, WH AF Wang Haiming Sun Jian Li Weipeng Wu Jianbo Chen Youjun Liu Wenhui TI Effects of soil nutrients and climate factors on belowground biomass in an alpine meadow in the source region of the Yangtze-Yellow rivers, Tibetan Plateau of China SO JOURNAL OF ARID LAND DT Article AB Improving our knowledge of the effects of environmental factors (e.g. soil conditions, precipitation and temperature) on belowground biomass in an alpine grassland is essential for understanding the consequences of carbon storage in this biome. The object of this study is to investigate the relative importance of soil nutrients and climate factors on belowground biomass in an alpine meadow in the source region of the Yangtze and Yellow rivers, Tibetan Plateau. Soil organic carbon (SOC), total nitrogen (TN) and total phosphorous (TP) contents and belowground biomass were measured at 22 sampling sites across an alpine meadow on the Tibetan Plateau. We analyzed the data by using the redundancy analysis to determine the main environmental factors affecting the belowground biomass and the contribution of each factor. The results showed that SOC, TN and TP were the main factors that influenced belowground biomass, and the contribution of SOC, TN and TP on biomass was in the range of 47.87%-72.06% at soil depths of 0-30 cm. Moreover, the combined contribution of annual mean temperature (AMT) and mean annual precipitation (MAP) on belowground biomass ranged from 0.92% to 4.10%. A potential mechanism for the differences in belowground biomass was caused by the variations in soil nitrogen and phosphorous, which were coupled with SOC. A significant correlation was observed between MAP and soil nutrients (SOC, TN and TP) at the soil depth of 0-10 cm (P < 0.05). We concluded that precipitation is an important driving force in regulating ecosystem functioning as reflected in variations of soil nutrients (SOC, TN and TP) and dynamics of belowground biomass in alpine grassland ecosystems. C1 [Wang Haiming; Wu Jianbo] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Sun Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Li Weipeng] China West Normal Univ, Land & Resource Coll, Nanchong 637002, Peoples R China. [Chen Youjun] Southwest Univ Nationalities Sichuan, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. [Liu Wenhui] Qinghai Acad Anim Sci & Vet Med, Xining 810016, Peoples R China. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. EM sunjian@igsnrr.ac.cn TC 13 Z9 15 PD DEC PY 2016 VL 8 IS 6 BP 881 EP 889 DI 10.1007/s40333-016-0055-2 UT WOS:000386126200006 DA 2023-03-23 ER PT J AU Wang, XY Yi, SH Wu, QB Yang, K Ding, YJ AF Wang, Xiaoyun Yi, Shuhua Wu, Qingbai Yang, Kun Ding, Yongjian TI The role of permafrost and soil water in distribution of alpine grassland and its NDVI dynamics on the Qinghai-Tibetan Plateau SO GLOBAL AND PLANETARY CHANGE DT Article AB Soil temperature and soil water are two important factors controlling vegetation growth. Climate warming and associated permafrost degradation might change these soil conditions and affect alpine grassland on the Qinghai-Tibetan Plateau. However, our current understanding of the role of soil temperature and water at the plateau scale is inadequate. In this study, we used plateau scale soil water content, frozen soil type, vegetation index and land surface temperature datasets to investigate the spatial distribution, limiting factors of vegetation growth and normalized difference vegetation index (NDVI) changing trends in two major alpine grasslands, alpine meadow and alpine steppe, in relation to soil temperature and soil water conditions. Our results showed that: 1) alpine meadow is mainly distributed in seasonal frozen soil areas (55.90% of alpine meadow) with a soil water content between 0.15 and 0.25 m(3)/m(3) and alpine steppe is mainly found in seasonal frozen and sub-stable permafrost areas (69.38% of alpine steppe) with a soil water content between 0.05 and 0.20 m(3)/m(3); 2) at the plateau scale, there were 35.6% (more in colder regions) of alpine meadow pixels and 33.6% (more in wetter regions) of alpine steppe pixels having increase NDVI changing trends during 1982-2012, respectively; and the values having decrease NDVI changing trends are 7.3% and 9.7%, respectively; and 3) the vegetation growth of alpine meadow is mainly limited by soil temperature, while that of alpine steppe is limited by both soil temperature and soil water. We also find the limiting factors of temperature or water can only explain <50% variation of vegetation growth trends in alpine grasslands. Our findings warrant the use of process-based ecosystem models to consider other factors, such as grazing, erosion and soil texture, among others, in addition to soil temperature and water to make proper projections when simulating the responses of vegetation growth to ;climate warming in alpine grasslands with different hydro-thermal conditions. (C) 2016 Elsevier B.V. All rights reserved. C1 [Wang, Xiaoyun] Lanzhou Univ, Key Lab Western Chinas Environm Syst, Minist Educ, Coll Earth & Environm Sci, Lanzhou 730000, Peoples R China. [Wang, Xiaoyun; Yi, Shuhua; Ding, Yongjian] Chinese Acad Sci, State Key Lab Cryospher Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Wu, Qingbai] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Yang, Kun] Chinese Acad Sci, Key Lab Tibetan Environm Changes & Land Surface P, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. RP Yi, SH (通讯作者)，Chinese Acad Sci, State Key Lab Cryospher Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. EM yis@lzb.ac.cn TC 52 Z9 59 PD DEC PY 2016 VL 147 BP 40 EP 53 DI 10.1016/j.gloplacha.2016.10.014 UT WOS:000390518500004 DA 2023-03-23 ER PT J AU Wu, LS Nie, YY Yang, ZR Zhang, J AF Wu Li-sha Nie Yuan-yang Yang Zhi-rong Zhang Jie TI Responses of soil inhabiting nitrogen-cycling microbial communities to wetland degradation on the Zoige Plateau, China SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB The wetlands on the Zoige Plateau have experienced serious degradation, with most of the original marsh being converted to marsh meadow or meadow. Based on the 3 wetland degradation stages, we determined the effects of wetland degradation on the structure and relative abundance of nitrogen-cycling (nitrogen-fixing, ammonia-oxidizing, and denitrifying) microbial communities in 3 soil types (intact wetland: marsh soil; early degrading wetland: marsh meadow soil; and degraded wetland: meadow soil) using 454-pyrosequencing. The structure and relative abundance of nitrogen-cycling microbial communities differed in the 3 soil types. Proteobacteria was the predominant phylum in most soil samples but the most abundant soil nitrogen-fixing and denitrifying microbial bacteria differed at the class, order, family, and genus levels among the 3 soil types. At the genus level, the majority of nitrogen-fixing bacterium sequences related to Bradyrhizobium were from marsh and marsh meadow soils; whereas those related to Geobacter originated from meadow soil. The majority of ammonia-oxidizing bacterium sequences related to Nitrosospira were from marsh (except for the 40-60 cm layer), marsh meadow and meadow soils; whereas those related to Candidatus Solibacter originated from 40-60 cm layer of marsh soil. The majority of denitrifying bacterium sequences related to Candidatus Solibacter and Anaeromyxobacter were from marsh and meadow soils; whereas those related to Herbaspirillum originated from meadow soil. The distribution of operational taxonomic units (OTUs) and species were correlated with soil type based upon Venn and Principal Coordinates Analysis (PCoA). Changes in soil type, caused by different water regimes were the most important factors influencing compositional changes in the nitrogen-fixing, ammonia-oxidizing, and denitrifying microbial communities. C1 [Wu Li-sha; Nie Yuan-yang; Yang Zhi-rong; Zhang Jie] Sichuan Univ, Coll Life Sci, Minist Educ, Key Lab Biol Resource & Ecol Environm, Chengdu 610065, Peoples R China. [Wu Li-sha] Chengdu Univ Tradit Chinese Med, Coll Med Technol, Chengdu 611137, Peoples R China. RP Zhang, J (通讯作者)，Sichuan Univ, Coll Life Sci, Minist Educ, Key Lab Biol Resource & Ecol Environm, Chengdu 610065, Peoples R China. EM balanu@126.com; yuanyang8238@163.com; bioyang@163.com; zhangjfy@scu.edu.cn TC 14 Z9 15 PD DEC PY 2016 VL 13 IS 12 BP 2192 EP 2204 DI 10.1007/s11629-016-4004-5 UT WOS:000391425900010 DA 2023-03-23 ER PT J AU Zhou, JH Cai, WT Qin, Y Lai, LM Guan, TY Zhang, XL Jiang, LH Du, H Yang, DW Cong, ZT Zheng, YR AF Zhou, Jihua Cai, Wentao Qin, Yue Lai, Liming Guan, Tianyu Zhang, Xiaolong Jiang, Lianhe Du, Hui Yang, Dawen Cong, Zhentao Zheng, Yuanrun TI Alpine vegetation phenology dynamic over 16 years and its covariation with climate in a semi-arid region of China SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Vegetation phenology is a sensitive indicator of ecosystem response to climate change, and plays an important role in the terrestrial biosphere. Improving our understanding of alpine vegetation phenology dynamics and the correlation with climate and grazing is crucial for high mountains in arid areas subject to climatic warming. Using a time series of SPOT Normalized Difference Vegetation Index (NDVI) data from 1998 to 2013, the start of the growing season (SOS), end of the growing season (EOS), growing season length (GSL), and maximum NDVI (MNDVI) were extracted using a threshold-based method for six vegetation groups in the Heihe River headwaters. Spatial and temporal patterns of SOS, EOS, GSL, MNDVI, and correlations with climatic factors and livestock production were analyzed. The MNDVI increased significantly in 58% of the study region, whereas SOS, EOS, and GSL changed significantly in <5% of the region. The MNDVI in five vegetation groups increased significantly by a range from 0.045 to 0.075. No significant correlation between SOS and EOS was observed in any vegetation group. The SOS and GSL were highly correlated with temperature in May and April-May, whereas MNDVI was correlated with temperature in August and July-August. The EOS of different vegetation groups was correlated with different climatic variables. Maximum and minimum temperature, accumulated temperature, and effective accumulated temperature showed stronger correlations with phenological metrics compared with those of mean temperature, and should receive greater attention in phenology modeling in the future. Meat and milk production were significantly correlated with the MNDVI of scrub, steppe, and meadow. Although the MNDVI increased in recent years, ongoing monitoring for rangeland degradation is recommended. (C) 2016 Elsevier B.V. All rights reserved. C1 [Zhou, Jihua; Cai, Wentao; Lai, Liming; Guan, Tianyu; Zhang, Xiaolong; Jiang, Lianhe; Du, Hui; Zheng, Yuanrun] Chinese Acad Sci, Inst Bot, Key Lab Resource Plants, Beijing Bot Garden,Wes China Subalpine Bot Garden, Beijing 100093, Peoples R China. [Zhou, Jihua; Cai, Wentao; Guan, Tianyu; Zhang, Xiaolong] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Qin, Yue; Yang, Dawen; Cong, Zhentao] Tsinghua Univ, Dept Hydraul Engn, State Key Lab Hydrosci & Engn, Beijing 100084, Peoples R China. RP Zheng, YR (通讯作者)，Chinese Acad Sci, Inst Bot, Key Lab Plant Resources, 20 Nanxincun, Beijing 100093, Peoples R China. EM zhengyr@ibcas.ac.cn TC 65 Z9 70 PD DEC 1 PY 2016 VL 572 BP 119 EP 128 DI 10.1016/j.scitotenv.2016.07.206 UT WOS:000387807200013 DA 2023-03-23 ER PT J AU Yi, SH Chen, JJ Qin, Y Xu, GW AF Yi, Shuhua Chen, Jianjun Qin, Yu Xu, Gaowei TI The burying and grazing effects of plateau pika on alpine grassland are small: a pilot study in a semiarid basin on the Qinghai-Tibet Plateau SO BIOGEOSCIENCES DT Article AB There is considerable controversy about the effects of plateau pika (Ochotona curzoniae, hereafter pika) on alpine grassland on the Qinghai-Tibet Plateau (QTP). On the one hand, pika is considered a keystone species. On the other hand, it is being poisoned. Although significant efforts have been made to study the effects of pika at a quadrat scale ( similar to m(2)), our knowledge about its distribution and effects at a larger scale is very limited. In this study, we investigated the direct effects, i.e., burying and grazing, of pika by upscaling field sampling at a quadrat scale to a plot scale (similar to 1000m(2)) by aerial photographing. Altogether 168 plots were set on four different types of alpine grassland in a semiarid basin on the QTP. Results showed that (1) the effects of pika pile burying on the reduction of vegetation cover, biomass, soil carbon, and nitrogen were less than 10 %, which was much smaller than the effects of bald patches; and (2) pika consumed 8-21% of annual net primary production of grassland. We concluded that the direct burying and grazing effects of pika on alpine grassland were minor in this region. The quadcopter is an efficient and economic tool for long-term repeated monitoring over large regions for further understanding the role of pika. C1 [Yi, Shuhua; Chen, Jianjun; Qin, Yu; Xu, Gaowei] Chinese Acad Sci, State Key Lab Cryosphere Sci, Cold & Arid Reg Environm & Engn Res Inst, 320 Donggang West Rd, Lanzhou 730000, Peoples R China. [Yi, Shuhua] Nantong Univ, Sch Geog Sci, 999 Tongjing Rd, Nantong 226007, Peoples R China. [Chen, Jianjun; Xu, Gaowei] Univ Chinese Acad Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China. RP Yi, SH (通讯作者)，Chinese Acad Sci, State Key Lab Cryosphere Sci, Cold & Arid Reg Environm & Engn Res Inst, 320 Donggang West Rd, Lanzhou 730000, Peoples R China.; Yi, SH (通讯作者)，Nantong Univ, Sch Geog Sci, 999 Tongjing Rd, Nantong 226007, Peoples R China. EM yis@lzb.ac.cn TC 29 Z9 39 PD NOV 23 PY 2016 VL 13 IS 22 BP 6273 EP 6284 DI 10.5194/bg-13-6273-2016 UT WOS:000388715300001 DA 2023-03-23 ER PT J AU Sun, G Wang, ZY Zhu-Barker, X Zhang, NN Wu, N Liu, L Lei, YB AF Sun, Geng Wang, Zhiyuan Zhu-Barker, Xia Zhang, Nannan Wu, Ning Liu, Lin Lei, Yanbao TI Biotic and abiotic controls in determining exceedingly variable responses of ecosystem functions to extreme seasonal precipitation in a mesophytic alpine grassland SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB As a result of global climate change, frequent and intensive extreme climate events are observed and predicted. These extreme climate events can change ecosystem functions through driving plant growth and mortality, as well as ecological and evolutionary processes into different directions. We simulated a 1-in-100-year extreme precipitation event in different plant growth seasons (i.e. spring, summer, or autumn) to investigate the functional responses of a mesophytic alpine grassland ecosystem to climate change in the Tibetan plateau. The results demonstrated that the seasonal distribution of extreme precipitation is a critical factor in determining soil microbial- and plant-productivity. The response of vegetation net primary productivity (NPP) to extreme precipitation depends on the growth seasons and plant types. Total NPP in the treatments experienced extreme precipitation in the early (spring), mid- (summer) and late (autumn) plant growth seasons were significant lower, higher, and no difference, respectively, compared with the control. Soil temperature and moisture were the key abiotic factors that affected ecosystem functions. For example, in the early plant growth season, no changes of soil moisture and the decreased temperature in response to the extreme precipitation resulted in a substantial decline in NPP. By contrast, in the mid-plant growth season, higher temperature and soil moisture elicited positive synergistic effects on plant growth and soil microbial processes. The increased sensitivity of above-ground NPP and the shift of dominant species from sedges to less palatable forbs might inevitably exaggerate the degradation of this grassland. Nevertheless, a high resilience index in the related ecological processes could potentially contribute to the grassland acclimation and stability, as most parameters returned to the similar levels as in the control after the extreme events ceased. Therefore, several synergistic or antagonistic mechanisms are hypothesized to operate in parallel or at different levels of organization and timescales. Further studies involving a range of different potential scenarios and longer periods are needed to predict the future climate change impacts on mesophytic grassland. (C) 2016 Elsevier B.V. All rights reserved. C1 [Sun, Geng; Wang, Zhiyuan; Zhang, Nannan; Wu, Ning] Chinese Acad Sci, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Peoples R China. [Sun, Geng; Wang, Zhiyuan; Zhang, Nannan; Wu, Ning] Chinese Acad Sci, Ecol Restorat Biodivers Conservat Key Lab Sichuan, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Wang, Zhiyuan] Yunnan Acad Agr Sci, Inst Agr Environm & Resources, Kunming 650205, Peoples R China. [Zhu-Barker, Xia] Univ Calif Davis, Dept Land Air & Water Resources, Davis, CA 95616 USA. [Liu, Lin] Sichuan Agr Univ, Coll Anim Sci & Technol, Chengdu 611130, Peoples R China. [Lei, Yanbao] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. RP Sun, G (通讯作者)，Chinese Acad Sci, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Peoples R China.; Sun, G (通讯作者)，Chinese Acad Sci, Ecol Restorat Biodivers Conservat Key Lab Sichuan, Chengdu Inst Biol, Chengdu 610041, Peoples R China.; Lei, YB (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. EM sungeng@cib.ac.cn; leiyb@imde.ac.cn TC 15 Z9 16 PD NOV 15 PY 2016 VL 228 BP 180 EP 190 DI 10.1016/j.agrformet.2016.07.010 UT WOS:000383295200015 DA 2023-03-23 ER PT J AU Du, ZY Wang, XD Liu, XP Cai, YJ AF Du Zi-yin Wang Xiao-dan Liu Xiu-ping Cai Yan-jiang TI Effects of rock fragments on yak dung greenhouse gas emissions on the Qinghai-Tibetan Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Dung deposition is an important pathway of nutrient return and redistribution in alpine grasslands of the Qinghai-Tibetan Plateau. To date, information on the greenhouse gas emissions of yak dung on alpine grasslands, especially where there are large amounts of rock fragments, is limited. Our aim, therefore, was to evaluate variations in N2O, CH4, and CO2 emissions from yak dung (CCD), and compare it to dung placed on rock fragments (RCD), alpine steppe soil (CSD), and a soil and rock fragment mixture (RSD) over a 30-day incubation period. The results showed that the total N2O emissions from treatments without soil were significantly (P < 0.05) lower than those from treatments with soil. The highest total CH4 emissions were detected in the CSD treatment, while CH4 losses from treatments without rock fragments were significantly (P < 0.05) greater than those with rock fragments. The total CO2 emissions from the RSD treatment was 6.30%-12.0% lower than those in the other three treatments. The soil beneath yak dung pats elevated the global warming potential (GWP), while the addition of rock fragments to the soil significantly (P < 0.05) decreased the GWP by reducing emissions of the three greenhouse gases. We therefore suggest that interactions between rock fragments and alpine steppe soil are effective in decreasing yak dung greenhouse gas emissions. This finding indicates that rock fragments are an effective medium for reducing greenhouse gas emissions from dung pats, and more attention should therefore be paid to evaluate its ecological impact in future studies. These results should help guide scientific assessments of regional GHG budgets in agricultural ecosystems where the addition of livestock manure to soils with large amounts of rock fragments is common. C1 [Du Zi-yin; Wang Xiao-dan; Cai Yan-jiang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Du Zi-yin] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Liu Xiu-ping] Chinese Acad Sci, Inst Genet & Dev Biol, Ctr Agr Resources Res, Shijiazhuang 050021, Peoples R China. RP Wang, XD; Cai, YJ (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. EM dzy@imde.ac.cn; wxd@imde.ac.cn; xiupingliu@sjziam.ac.cn; yanjiangcai@163.com TC 3 Z9 3 PD NOV PY 2016 VL 13 IS 11 BP 2006 EP 2014 DI 10.1007/s11629-015-3798-x UT WOS:000387032600009 DA 2023-03-23 ER PT J AU Li, YK Ouyang, JZ Lin, L Xu, XL Zhang, FW Du, YG Liu, SL Cao, GM Han, F AF Li Yi-kang Ouyang Jing-zheng Lin Li Xu Xing-liang Zhang Fa-wei Du Yan-gong Liu Shu-li Cao Guang-min Han Fa TI Alterations to biological soil crusts with alpine meadow retrogressive succession affect seeds germination of three plant species SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Biological soil crusts (BSCs) are the important components of alpine meadow ecosystems. The extent and morphology of BSCs vary greatly with alpine meadow retrogressive succession due to grazing pressure. There is significant interest in impacts of crust composition on plant seed germination, especially in (semi-) arid environments. However, little is known about the influences of BSCs, and their associations with alpine meadow succession, on germination of typical alpine meadow vascular plant species. In a full factorial common-garden experiment, we studied effects of: (1) crust type, (2) seed position, and (3) surface texture on seed germination. We chose three typical alpine meadow plant species (i.e. Poa pratensis, Tibetia himalaica and Potentillen nivea), which belonged to different functional groups (graminoids, legumes, and forbs) and play important roles in all alpine meadow succession stages. Crust type and seed position influenced seed germination, and the inhibitory effects of BSCs depended on the crust type and seed species tested. The major factors influencing seed germination were BSC type, seed position, soil texture, and the interactions between BSC type and seed position; species and seed position; species and surface texture; and species, crust type, and surface texture. Cyanobacteria crust significantly inhibited germination of all seeds. Seed position also had a significant effect on seed germination (p < 0.001). Fewer seedlings germinated on the surface than below the surface, this was especially true for P. nivea. seeds within cyanobacteria and lichen crusts. Only germination rates of T. himalaica on the soil surface were significantly correlated with plant occurrence frequency within the alpine meadow community. The poor correlation for the other two species is possibly that they are perennials. Our results clearly demonstrated that BSCs can be biological filters during seed germination, depending on the BSC succession stage. Through their influences on seed germination, BSCs can strongly influence community assemblages throughout alpine meadow retrogressive succession. C1 [Li Yi-kang; Lin Li; Zhang Fa-wei; Du Yan-gong; Liu Shu-li; Cao Guang-min; Han Fa] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. [Li Yi-kang; Zhang Fa-wei; Liu Shu-li] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Xu Xing-liang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Ouyang Jing-zheng] Liancheng Natl Nat Reserve Gansu Prov, Yongdeng Country 730000, Peoples R China. RP Han, F (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. EM liyikang501@163.com; oyjztt@163.com; hanxiao_2000_00@126.com; xuxingl@hotmail.com; flingzhang@gmail.com; ygdu@nwipb.cas.cn; liushuli0203@163.com; caogm@nwipb.cas.cn; hanfa@nwipb.cas.cn TC 0 Z9 3 PD NOV PY 2016 VL 13 IS 11 BP 1995 EP 2005 DI 10.1007/s11629-016-3917-3 UT WOS:000387032600008 DA 2023-03-23 ER PT J AU Wang, Y Wesche, K AF Wang, Yun Wesche, Karsten TI Vegetation and soil responses to livestock grazing in Central Asian grasslands: a review of Chinese literature SO BIODIVERSITY AND CONSERVATION DT Review AB Grasslands in northern China and the Qinghai-Tibetan plateau are particularly important to both ecosystem functioning and pastoral livelihoods. Although there are numerous degradation studies on the effect of livestock grazing across the region, they are largely only published in Chinese, and most focus on single sites. Based on case studies from 100 sites, covering a mean annual precipitation gradient of 95-744 mm, we present a comprehensive, internationally accessible review on the impact of livestock grazing on vegetation and soils. We compared ungrazed or slightly grazed sites with moderately and heavily grazed sites by evaluating changes in two indicator groups: vegetation (plant species richness, vegetation cover, aboveground biomass, belowground biomass and root/shoot ratio) and soil (pH, bulk density, organic C, total N, total P and available P). Most indicators declined with intensified grazing, while soil pH, bulk density and belowground biomass increased. Available P showed no clear response. Variables within indicator groups were mostly linearly correlated at a given grazing intensity. Relative grazing effects on different indicators varied along specific abiotic gradients. Grazing responses of plant species richness, aboveground biomass, soil bulk density, total N and available P interacted with precipitation patterns, while grazing effects on belowground biomass were influenced by temperature. Elevation had impact on grazing responses of aboveground biomass and soil organic carbon. Complex grazing effects reflect both methodological inconsistency and ecological complexity. Further assessments should consider specific characteristics of different indicators in the context of the local environment. C1 [Wang, Yun; Wesche, Karsten] Senckenberg Museum Nat Hist Gorlitz, POB 300154, D-02806 Gorlitz, Germany. [Wesche, Karsten] German Ctr Integrat Biodivers Res iDiv, Deutsch Pl 5e, D-04103 Leipzig, Germany. RP Wang, Y (通讯作者)，Senckenberg Museum Nat Hist Gorlitz, POB 300154, D-02806 Gorlitz, Germany. EM yunwang.hh@gmail.com TC 101 Z9 114 PD NOV PY 2016 VL 25 IS 12 SI SI BP 2401 EP 2420 DI 10.1007/s10531-015-1034-1 UT WOS:000386500700011 DA 2023-03-23 ER PT J AU Yu, CQ Zhang, XZ Zhang, J Li, SW Song, CQ Fang, YZ Wurst, S Wu, JS AF Yu, Chengqun Zhang, Xianzhou Zhang, Jing Li, Shaowei Song, Chunqiao Fang, Yuzhi Wurst, Susanne Wu, Jianshuang TI Grazing Exclusion to Recover Degraded Alpine Pastures Needs Scientific Assessments across the Northern Tibetan Plateau SO SUSTAINABILITY DT Article AB The northern Tibetan Plateau is the most traditional and important semi-nomadic region in Tibet. The alpine vegetation is sensitive and vulnerable to climate change and human activities, and is also important as an ecological security in protecting the headwaters of major rivers in Asia. Therefore, the Tibetan alpine grasslands have fundamental significance to both Mainland China and South Asia. The pasture degradation, however, likely threatens the livelihood of residents and the habitats of wildlife on this plateau. Since 2004, the government has launched a series of ecological restoration projects and economic compensatory payment polices. Many fences were additionally built on degraded pastures to prevent new degradation, to promote functionality recovery, and to balance the stocking rate with forage productivity. The grazed vs. fenced paired pastures across different zonal grassland communities along evident environmental gradients provide us with a natural comparative experiment platform to test the relative contributions of natural and anthropogenic factors. This study critically reviews the background, significance of and debates on short-term grazing exclusion with fences in this region. We also aim to figure out scientific and standardized workflows for assessing the effectiveness of grazing exclusion and compensatory payments in the future. C1 [Yu, Chengqun; Zhang, Xianzhou; Li, Shaowei; Fang, Yuzhi; Wu, Jianshuang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Zhang, Jing] Beijing Normal Univ, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China. [Song, Chunqiao] Univ Calif Los Angeles, Dept Geog, Los Angeles, CA 90095 USA. [Wurst, Susanne; Wu, Jianshuang] Free Univ Berlin, Dahlem Ctr Plant Sci, Funct Biodivers, D-14195 Berlin, Germany. RP Wu, JS (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China.; Wu, JS (通讯作者)，Free Univ Berlin, Dahlem Ctr Plant Sci, Funct Biodivers, D-14195 Berlin, Germany. EM yucq@igsnrr.ac.cn; zhangxz@igsnrr.ac.cn; jingzhang@bnu.edu.cn; leesw@igsnrr.ac.cn; chunqiao@ucla.edu; fanyuzhi@igsnrr.ac.cn; s.wurst@fu-berlin.de; wujs.07s@igsnrr.ac.cn TC 33 Z9 36 PD NOV PY 2016 VL 8 IS 11 AR 1162 DI 10.3390/su8111162 UT WOS:000389316200082 DA 2023-03-23 ER PT J AU Zou, JR Luo, CY Xu, XL Zhao, N Zhao, L Zhao, XQ AF Zou, Jingru Luo, Caiyun Xu, Xingliang Zhao, Na Zhao, Liang Zhao, Xinquan TI Relationship of plant diversity with litter and soil available nitrogen in an alpine meadow under a 9-year grazing exclusion SO ECOLOGICAL RESEARCH DT Article AB Grazing exclusion is widely used globally to restore degraded grasslands. Plant diversity has important impacts on grassland ecosystem functions, including grassland productivity and carbon storage. In this study, we selected a Kobresia meadow on the Qinghai-Tibetan Plateau to investigate how grazing exclusion affects plant diversity. Inorganic nitrogen (NH4 (+) and NO3 (-)) was also measured because its availability impacts plant growth. We found that plant diversity in the meadow was significantly lower under grazing exclusion (fenced meadow) for 9 years compared with moderate grazing. Accumulated litter was significantly higher under grazing exclusion (386.41 g m(-2)) compared with grazing (58.77 g m(-2)). Soil inorganic nitrogen at 0-5 cm depth was significantly higher under grazing exclusion (13.60 x 10(-2) g kg(-1)) than under grazing (9.40 x 10(-2) g kg(-1)). The composition of the four functional groups (grasses, sedges, legumes, and forbs) might alter in response to significant changes in the amount of litter and soil available nitrogen content under grazing exclusion compared with grazing. However, the enhanced soil available nitrogen content showed weak feedbacks on plant diversity. In conclusion, light limitation induced by increased amounts of litter may be the main factor causing decreased plant diversity in grazing-excluded meadows compared with moderately grazed meadows. C1 [Zou, Jingru; Luo, Caiyun; Zhao, Na; Zhao, Liang; Zhao, Xinquan] Chinese Acad Sci, Northwest Plateau Inst Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. [Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Zou, Jingru] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Zhao, XQ (通讯作者)，Chinese Acad Sci, Northwest Plateau Inst Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Peoples R China. EM xqzhao@nwipb.cas.cn TC 16 Z9 20 PD NOV PY 2016 VL 31 IS 6 BP 841 EP 851 DI 10.1007/s11284-016-1394-3 UT WOS:000387344900009 DA 2023-03-23 ER PT J AU Mu, JP Zeng, YL Wu, QG Niklas, KJ Niu, KC AF Mu, Junpeng Zeng, Yuling Wu, Qinggui Niklas, Karl J. Niu, Kechang TI Traditional grazing regimes promote biodiversity and increase nectar production in Tibetan alpine meadows SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Pastoralists claim that traditional management practices involving light to moderate grazing ensure sustainable yield and promote the multifunctional services provided by rangeland ecosystems. Nectar production is a key ecosystem function crucial to successful apiculture and to the sustainability of services provided by pollinators in the Tibetan alpine rangeland. Here, we evaluated whether traditional (light to moderate) grazing promotes plant biodiversity and nectar production at the level of individual plants and at the level of an entire community. We compared plant species diversity and nectar production of the dominant nectariferous species (Saussurea nigrescens) at the individual plant level and at the community level in ungrazed, lightly grazed, moderately grazed, and heavily grazed plots in each of three Tibetan alpine meadow sites. Individual nectar production was quantified as nectar volume x floret number per capitulum x capitulum per plant. Community nectar production was calculated as individual nectar production x the number of flowering plants per 1.0 m(2) plot. We found that nectar production at the floret, individual, and community levels was significantly higher in lightly and moderately grazed plots compared to heavily grazed or ungrazed plots. This somewhat counterintuitive observation (particularly with regard to ungrazed plots) resulted from the fact that light and moderate grazing increased floret and capitulum number, and the number of flowering individuals per plot as a result of lowered competition for light. Moreover, species richness was significantly correlated with nectar production (as a result of light to moderate grazing) both at the individual level and at the community level. These results support the traditional view that light to moderate grazing not only promotes plant biodiversity but also ensures a sustainable yield in nectar production (and forage). Thus, traditional grazing management practices are more "eco-friendly" compared to recent and widespread practices involving either grazing exclusion or overgrazing in the Tibetan rangelands examined in this study. (C) 2016 Elsevier B.V. All rights reserved. C1 [Mu, Junpeng; Zeng, Yuling; Wu, Qinggui] Mianyang Normal Univ, Ecol Secur, Mianyang 621000, Peoples R China. [Mu, Junpeng; Zeng, Yuling; Wu, Qinggui] Mianyang Normal Univ, Protect Key Lab Sichuan Prov, Mianyang 621000, Peoples R China. [Mu, Junpeng; Niu, Kechang] Nanjing Univ, Dept Biol, Nanjing 210023, Jiangsu, Peoples R China. [Niklas, Karl J.] Cornell Univ, Plant Biol Sect, Sch Integrat Plant Sci, Ithaca, NY 14853 USA. RP Niu, KC (通讯作者)，Nanjing Univ, Dept Biol, Nanjing 210023, Jiangsu, Peoples R China. EM kechangniu@nju.edu.cn TC 24 Z9 26 PD OCT 3 PY 2016 VL 233 BP 336 EP 342 DI 10.1016/j.agee.2016.09.030 UT WOS:000389088400036 DA 2023-03-23 ER PT J AU Huang, K Zhang, YJ Zhu, JT Liu, YJ Zu, JX Zhang, J AF Huang, Ke Zhang, Yangjian Zhu, Juntao Liu, Yaojie Zu, Jiaxing Zhang, Jing TI The Influences of Climate Change and Human Activities on Vegetation Dynamics in the Qinghai-Tibet Plateau SO REMOTE SENSING DT Article AB Grasslands occupy nearly three quarters of the land surface of the Qinghai-Tibet plateau ( QTP) and play a critical role in regulating the ecological functions of the QTP. Ongoing climate change and human interference have greatly affected grasslands on the QTP. Differentiating human-induced and climate-driven vegetation changes is vital for both ecological understanding and the management of husbandry. In this study, we employed statistical analysis of annual records, various sources of remote sensing data, and an ecosystem process model to calculate the relative contribution of climate and human activities to vegetation vigor on the QTP. The temperature, precipitation and the intensity and spatial pattern of livestock grazing differed between the periods prior to and after the year 2000, which led to different vegetation dynamics. Overall, increased temperature and enhanced precipitation favored vegetation growth. However, their combined effects exhibited strong spatial heterogeneity. Specifically, increased temperature restrained vegetation growth in dry steppe regions during a period of slightly increasing precipitation from 1986 to 2000 and in meadow regions during a period of precipitation decline during 2000-2011, thereby making precipitation a dominant factor. An increase in precipitation tended to enhance vegetation growth in wet meadow regions during warm periods, and temperature was the limiting factor in Tibet during dry periods. The dominant role played by climate and human activities differed with location and targeted time period. Areas dominated by human activities are much smaller than those dominated by climate. The effects of grazing on grassland pasture were more obvious under unfavorable climate conditions than under suitable ones. C1 [Huang, Ke; Zhang, Yangjian; Zhu, Juntao; Liu, Yaojie; Zu, Jiaxing] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Huang, Ke; Liu, Yaojie; Zu, Jiaxing] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Yangjian] Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhang, Jing] Beijing Normal Univ, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China. RP Zhang, YJ; Zhu, JT (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China.; Zhang, YJ (通讯作者)，Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. EM huangk.13b@igsnrr.ac.cn; zhangyj@igsnrr.ac.cn; zhujt@igsnrr.ac.cn; liuyj.14b@igsnrr.ac.cn; zujx.15b@igsnrr.ac.cn; jingzhang@bnu.edu.cn TC 165 Z9 174 PD OCT PY 2016 VL 8 IS 10 AR 876 DI 10.3390/rs8100876 UT WOS:000387357300090 DA 2023-03-23 ER PT J AU Liu, SL Du, YG Zhang, FW Lin, L Li, YK Guo, XW Li, Q Cao, GM AF Liu Shu-li Du Yan-gong Zhang Fa-wei Lin Li Li Yi-kang Guo Xiao-wei Li Qian Cao Guang-min TI Distribution of soil carbon in different grassland types of the Qinghai-Tibetan Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Accurate estimate of soil carbon storage is essential to reveal the role of soil in global carbon cycle. However, there is large uncertainty on the estimation of soil organic carbon (SOC) storage in grassland among previous studies, and the study on soil inorganic carbon (SIC) is still lack. We surveyed 153 sites during plant peak growing season and estimated SOC and SIC for temperate desert, temperate steppe, alpine steppe, steppe meadow, alpine meadow and swamp, which covered main grassland in the Qinghai Plateau during 2011 to 2012. The results showed that the vertical and spatial distributions of SOC and SIC varied by grassland types. The SOC amount mainly decreased from southeast to northwest, whereas the SIC amount increased from southeast to northwest. The magnitude of SOC amount in the top 50 cm across grassland types ranked by: swamp > alpine meadow > steppe meadow > temperate steppe > alpine steppe > temperate desert, while the SIC amount showed an opposite order. There was a great deal of variation in proportion of SOC and SIC among different grassland types (from 55.17 to 94.59 for SOC and 5.14 to 44.83 for SIC). The total SOC and SIC storage was 5.78 Pg and 1.37 Pg, respectively, in the top 50 cm of soil in Qinghai Province. The mixed linear model revealed that grassland types was the predominant factor in spatial variations of SOC amount while grassland types and soil pH accounted for those of SIC amount. Our results suggested that the community shift of alpine meadow towards alpine grassland induced by climate warming would decrease carbon sequestration capacity by 6.0 kg C m(2). C1 [Liu Shu-li; Du Yan-gong; Zhang Fa-wei; Lin Li; Li Yi-kang; Guo Xiao-wei; Li Qian; Cao Guang-min] Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai 810001, Peoples R China. [Liu Shu-li] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Cao, GM (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Qinghai 810001, Peoples R China. EM liushuli0203@163.com; ygdu@nwipb.cas.cn; fwzhang@nwipb.cas.cn; hanxiao_2000_00@126.com; liyikang501@163.com; xwguo1206@163.com; liqian@nwipb.cas.cn; caogm@nwipb.ac.cn TC 13 Z9 13 PD OCT PY 2016 VL 13 IS 10 BP 1806 EP 1817 DI 10.1007/s11629-015-3764-7 UT WOS:000386502400009 DA 2023-03-23 ER PT J AU Hoppe, F Zhusui Kyzy, T Usupbaev, A Schickhoff, U AF Hoppe, Franziska Zhusui Kyzy, Taalaigul Usupbaev, Adilet Schickhoff, Udo TI Rangeland degradation assessment in Kyrgyzstan: vegetation and soils as indicators of grazing pressure in Naryn Oblast SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Rangelands occupy more than 80% of the agricultural land in Kyrgyzstan. At least 30% of Kyrgyz pasture areas are considered to be subject to vegetation and soil degradation. Since animal husbandry is the economic basis to sustain people's livelihoods, rangeland degradation presents a threat for the majority of the population. We present for the first time an ecological assessment of different pasture types in a remote area of the Naryn Oblast, using vegetation and soils as indicators of rangeland conditions. We analysed the current degree of utilization (grazing pressure), the amount of biomass, soil samples, and vegetation data, using cluster analysis as well as ordination techniques. Winter pastures (kyshtoo) are characterized by higher pH values (average of 7.27) and lower organic matter contents (average of 12.83%) compared to summer pastures (dzailoo) with average pH values of 6.03 and average organic matter contents of 21.05%. Additionally, summer pastures show higher above-ground biomass, and higher species richness and diversity. Our results support the hypothesis that winter pastures, which are located near settlements, suffer from over-utilisation, while the more distant summer pastures are subjected to much lower grazing pressure. C1 [Hoppe, Franziska; Schickhoff, Udo] CEN Ctr Earth Syst Res & Sustainabil, Inst Geog, D-20146 Hamburg, Germany. [Zhusui Kyzy, Taalaigul; Usupbaev, Adilet] Natl Acad Sci Kyrgyz Republ, Inst Biol & Pedol, Lab Flora, Bishkek 720071, Kyrgyzstan. RP Hoppe, F (通讯作者)，CEN Ctr Earth Syst Res & Sustainabil, Inst Geog, D-20146 Hamburg, Germany. EM Franziska.hoppe@uni-hamburg.de; talaykul@bk.ru; adilet.usupbaev@mail.ru; udo.schickhoff@uni-hamburg.de TC 19 Z9 19 PD SEP PY 2016 VL 13 IS 9 BP 1567 EP 1583 DI 10.1007/s11629-016-3915-5 UT WOS:000382748500005 DA 2023-03-23 ER PT J AU Hu, YF Peng, JJ Yuan, S Shu, XY Jiang, SL Pu, Q Ma, KY Yuan, CM Chen, GD Xiao, HH AF Hu, Yu-Fu Peng, Jia-Jia Yuan, Shu Shu, Xiang-Yang Jiang, Shuang-Long Pu, Qin Ma, Ke-Ya Yuan, Cheng-Ming Chen, Guang-Deng Xiao, Hai-Hua TI Influence of ecological restoration on vegetation and soil microbiological properties in Alpine-cold semi-humid desertified land SO ECOLOGICAL ENGINEERING DT Article AB Recently desertification of Alpine-cold semi-humid grassland has become increasingly serious on the eastern edge of the Qinghai-Tibet plateau. However, the restoration and control of desertified land in these areas have not received enough attention as in arid and semi-arid areas, and little is known about the vegetation community and soil microbiological properties during the ecological restoration in Alpine cold semi-humid desertified areas. In this paper, the method of fencing, removing grazing and planting Tamarix ramosissima was taken as the measure for ecological restoration of Alpine-cold desertified land in Northwest Sichuan. The results showed ecological restoration resulted in significant improvement in the height, coverage, density, biomass, and diversity of vegetation communities, numbers of soil microorganisms (including bacteria, actinomycetes and fungi). Microbial biomass carbon and nitrogen, and urease, invertase and protease activities increased after the restoration, especially in the 0-20 cm layer. These trends increased with increasing restoration age but decreased with increasing soil depth. Ecological restoration by fencing, non-grazing and planting T. ramosissima is therefore considered an effective and applicable measure to restore vegetation and soil microbiological properties and control desertification in the Northwest Sichuan, and is recommended for adoption in Alpine-cold semi-humid sandy areas on a large scale. (C) 2016 Elsevier B.V. All rights reserved. C1 [Hu, Yu-Fu; Peng, Jia-Jia; Yuan, Shu; Shu, Xiang-Yang; Jiang, Shuang-Long; Pu, Qin; Ma, Ke-Ya; Yuan, Cheng-Ming; Chen, Guang-Deng; Xiao, Hai-Hua] Sichuan Agr Univ, Coll Resources Sci & Technol, Chengdu 611130, Peoples R China. RP Hu, YF (通讯作者)，Sichuan Agr Univ, Coll Resources Sci & Technol, Chengdu 611130, Peoples R China. EM huyufu@sicau.edu.cn TC 27 Z9 33 PD SEP PY 2016 VL 94 BP 88 EP 94 DI 10.1016/j.ecoleng.2016.05.061 UT WOS:000381636400012 DA 2023-03-23 ER PT J AU Wang, ZK Ding, LB Wang, JS Zuo, XL Yao, SC Feng, JG AF Wang, Zhikai Ding, Lubin Wang, Jingsheng Zuo, Xiaolong Yao, Shuaichen Feng, Jiguang TI Effects of root diameter, branch order, root depth, season and warming on root longevity in an alpine meadow SO ECOLOGICAL RESEARCH DT Article AB Fine root is of importance in biogeochemical cycles especially in terrestrial ecosystems. The lack of understanding of the factors controlling root lifespan has made accurate prediction of carbon flow and nutrient cycling difficult. A controlled warming experiment was performed in an alpine meadow on the northern Tibetan Plateau (near Nagchu Town). We used a minirhizotron technique to measure root dynamics in situ during the growing season of 2013 and 2014 and survival analyses to assess root lifespan and the effects of root diameter, branch order, birth season, root depth and warming on root lifespan. Root diameter, branch order and root depth were all positively correlated with root lifespan. With an increase in diameter of 0.1 mm, mortality hazard ratio of roots declined by 19.3 %. An increase in one level in branch order was associated with a decrease of 43.8 % in root death ratio. Compared with roots born in May-mid-July, the mortality hazard ratio of roots born in late July-August and September-October reduced by 26.8 and 56.5 %, respectively. In warming treatments, roots tended to be thinner, less branched and deeper, and there was a higher proportion of roots born in spring compared to ambient conditions. Warming shortened the median root lifespan 44 days. However, in single warming condition, root diameter had no significant influence on root lifespan. Root diameter, branch order, root depth and season of birth were all factors affecting root lifespan in the alpine meadow; however, root branch order was dominant. C1 [Wang, Zhikai; Wang, Jingsheng] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, 11A Datun Rd, Beijing 100101, Peoples R China. [Wang, Zhikai; Ding, Lubin; Wang, Jingsheng; Zuo, Xiaolong; Yao, Shuaichen; Feng, Jiguang] Renmin Univ China, Sch Environm & Nat Resources, 59 Zhongguancun St, Beijing 100872, Peoples R China. RP Wang, JS (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, 11A Datun Rd, Beijing 100101, Peoples R China.; Wang, JS (通讯作者)，Renmin Univ China, Sch Environm & Nat Resources, 59 Zhongguancun St, Beijing 100872, Peoples R China. EM michealwzk@163.com; wangjsh@igsnrr.ac.cn TC 10 Z9 14 PD SEP PY 2016 VL 31 IS 5 BP 739 EP 747 DI 10.1007/s11284-016-1385-4 UT WOS:000382141400015 DA 2023-03-23 ER PT J AU Zhang, Y Zhang, CB Wang, ZQ Chen, YZ Gang, CC An, R Li, JL AF Zhang, Ying Zhang, Chaobin Wang, Zhaoqi Chen, Yizhao Gang, Chengcheng An, Ru Li, Jianlong TI Vegetation dynamics and its driving forces from climate change and human activities in the Three-River Source Region, China from 1982 to 2012 SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The Three-River Source Region (TRSR), a region with key importance to the ecological security of China, has undergone climate changes and a shift in human activities driven by a series of ecological restoration projects in recent decades. To reveal the spatiotemporal dynamics of vegetation dynamics and calculate the contributions of driving factors in the TRSR across different periods from 1982 to 2012, net primary productivity (NPP) estimated using the Carnegie-Ames-Stanford approach model was used to assess the status of vegetation. The actual effects of different climatic variation trends on interannual variation in NPP were analyzed. Furthermore, the relationships of NPP with different climate factors and human activities were analyzed quantitatively. Results showed the following: from 1982 to 2012, the average NPP in the study area was 187.37 g cm(-2) yr(-1). The average NPP exhibited a fluctuation but presented a generally increasing trend over the 31-year study period, with an increase rate of 1.31 g cm(-2) yr(-2). During the entire study period, the average contributions of temperature, precipitation, and solar radiation to NPP interannual variation over the entire region were 0.58, 0.73, and 0.09 g cm(-2) yr(-2), respectively. Radiation was the climate factor with the greatest influence on NPP interannual variation. The factor that restricted NPP increase changed from temperature and radiation to precipitation. The average contributions of climate change and human activities to NPP interannual variation were 1.40 g cm(-2) yr(-2) and -0.08 g cm(-2) yr(-2), respectively. From 1982 to 2000, the general climate conditions were favorable to vegetation recovery, whereas human activities had a weaker negative impact on vegetation growth. From 2001 to 2012, climate conditions began to have a negative impact on vegetation growth, whereas human activities made a favorable impact on vegetation recovery. (c) 2016 Elsevier B.V. All rights reserved. C1 [Zhang, Ying; Zhang, Chaobin; Wang, Zhaoqi; Chen, Yizhao; Gang, Chengcheng; Li, Jianlong] Nanjing Univ, Sch Life Sci, Xianlin Rd 163, Nanjing 210046, Jiangsu, Peoples R China. [An, Ru] Hohai Univ, Sch Earth Sci & Engn, Xikang Rd 129, Nanjing 210098, Jiangsu, Peoples R China. RP Li, JL (通讯作者)，Nanjing Univ, Sch Life Sci, Xianlin Rd 163, Nanjing 210046, Jiangsu, Peoples R China. EM lijianlongnju@163.com TC 189 Z9 220 PD SEP 1 PY 2016 VL 563 BP 210 EP 220 DI 10.1016/j.scitotenv.2016.03.223 UT WOS:000377792800024 DA 2023-03-23 ER PT J AU Zhao, JX Li, X Li, RC Tian, LH Zhang, T AF Zhao, Jingxue Li, Xiang Li, Ruicheng Tian, Lihua Zhang, Tao TI Effect of grazing exclusion on ecosystem respiration among three different alpine grasslands on the central Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB Alpine grasslands are currently experiencing an increasing threat from overgrazing, and grazing exclusion has been widely used as a simple and effective method for restoring degraded grasslands on the Tibetan Plateau (TP). This paper studied effects of grazing exclusion on ecosystem respiration (Re), plant and soil characteristics for two growing season (2012 and 2013) in three alpine grasslands (alpine steppe, alpine meadow and swamp meadow) on the central TP. Grazing exclusion enhanced plant height, total cover, aboveground biomass and belowground biomass in all the three alpine grasslands. Grazing exclusion increased Re in alpine steppe and alpine meadow, but decreased Re in swamp meadow. Soil temperature and soil moisture well explained the seasonal variations of Re in alpine steppe and alpine meadow. However, soil temperature, rather than soil moisture, was the major environment factor controlling the seasonal variation of Re in swamp meadows. The temperature sensitivity of Re (Q(10)) was higher in swamp meadow and alpine meadow compared with alpine steppe. Grazing exclusion had a slight tendency to decrease Q(10) in alpine steppe and alpine meadow, but increase Q(10) in swamp meadows. Results suggest that grazing exclusion effects on Re and Q(10) of alpine grassland were determined by vegetation types. (C) 2016 Elsevier B.V. All rights reserved. C1 [Zhao, Jingxue; Li, Xiang] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Bldg 3,16 Lin Cui Rd, Beijing 100101, Peoples R China. [Zhao, Jingxue; Li, Ruicheng] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Tian, Lihua] Southwest Univ Nationalities, Inst Qinghai Tibetan Plateau, Chengdu 610041, Peoples R China. [Zhang, Tao] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730000, Peoples R China. RP Zhao, JX (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Bldg 3,16 Lin Cui Rd, Beijing 100101, Peoples R China. EM zhaojx@itpcas.ac.cn TC 21 Z9 22 PD SEP PY 2016 VL 94 BP 599 EP 607 DI 10.1016/j.ecoleng.2016.06.112 UT WOS:000381636400065 DA 2023-03-23 ER PT J AU Zhang, Y Dong, SK Gao, QZ Liu, SL Zhou, HK Ganjurjav, H Wang, XX AF Zhang, Yong Dong, Shikui Gao, Qingzhu Liu, Shiliang Zhou, Huakun Ganjurjav, Hasbagan Wang, Xuexia TI Climate change and human activities altered the diversity and composition of soil microbial community in alpine grasslands of the Qinghai-Tibetan Plateau SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Alpine ecosystems are known to be sensitive to climate change and human disturbances. However, the knowledge about the changes of their underground microbial communities is inadequate. We explored the diversity and structure of soil bacterial and fungal communities using Ilumina MiSeq sequencing in native alpine grasslands (i.e. the alpine meadow, alpine steppe) and cultivated grassland of the Qinghai-Tibetan Plateau (QTP) under three-year treatments of overgrazing, warming and enhanced rainfall. Enhanced rainfall rather than warming significantly reduced soil microbial diversity in native alpine grasslands. Variable warming significantly reduced it in the cultivated grassland. Over 20% and 40% variations of microbial diversity could be explained by soil nutrients and moisture in the alpine meadow and cultivated grassland, separately. Soil microbial communities could be clustered into different groups according to different treatments in the alpine meadow and cultivated grassland. For the alpine steppe, with the lowest soil nutrients and moistures, <10% variations of microbial diversity was explained by soil properties; and the soil microbial communities among different treatments were similar. The soil microbial community in the cultivated grassland was varied from it in native grasslands. Over 50% variations of soil microbial communities among different treatments were explained by soil nutrients and moisture in each grassland type. Our results suggest that climate change and human activities strongly affected soil microbial communities by changing soil nutrients and moistures in alpine grassland ecosystems. (C) 2016 Elsevier B.V. All rights reserved. C1 [Zhang, Yong; Dong, Shikui; Liu, Shiliang] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. [Gao, Qingzhu; Ganjurjav, Hasbagan; Wang, Xuexia] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Zhou, Huakun] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Peoples R China. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China.; Dong, SK (通讯作者)，19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM dongshikui@sina.com; gaoqzh@ami.ac.cn TC 130 Z9 144 PD AUG 15 PY 2016 VL 562 BP 353 EP 363 DI 10.1016/j.scitotenv.2016.03.221 UT WOS:000377372400036 DA 2023-03-23 ER PT J AU Ding, JZ Li, F Yang, GB Chen, LY Zhang, BB Liu, L Fang, K Qin, SQ Chen, YL Peng, YF Ji, CJ He, HL Smith, P Yang, YH AF Ding, Jinzhi Li, Fei Yang, Guibiao Chen, Leiyi Zhang, Beibei Liu, Li Fang, Kai Qin, Shuqi Chen, Yongliang Peng, Yunfeng Ji, Chengjun He, Honglin Smith, Pete Yang, Yuanhe TI The permafrost carbon inventory on the Tibetan Plateau: a new evaluation using deep sediment cores SO GLOBAL CHANGE BIOLOGY DT Article AB The permafrost organic carbon (OC) stock is of global significance because of its large pool size and the potential positive feedback to climate warming. However, due to the lack of systematic field observations and appropriate upscaling methodologies, substantial uncertainties exist in the permafrost OC budget, which limits our understanding of the fate of frozen carbon in a warming world. In particular, the lack of comprehensive estimates of OC stocks across alpine permafrost means that current knowledge on this issue remains incomplete. Here, we evaluated the pool size and spatial variations of permafrost OC stock to 3m depth on the Tibetan Plateau by combining systematic measurements from a substantial number of pedons (i.e. 342 three-metre-deep cores and 177 50-cm-deep pits) with a machine learning technique (i.e. support vector machine, SVM). We also quantified uncertainties in permafrost carbon budget by conducting Monte Carlo simulations. Our results revealed that the combination of systematic measurements with the SVM model allowed spatially explicit estimates to be made. The OC density (OC amount per unit area, OCD) exhibited a decreasing trend from the south-eastern to the north-western plateau, with the exception that OCD in the swamp meadow was substantially higher than that in surrounding regions. Our results also demonstrated that Tibetan permafrost stored a large amount of OC in the top 3m, with the median OC pool size being 15.31 Pg C (interquartile range: 13.03-17.77Pg C). 44% of OC occurred in deep layers (i.e. 100-300cm), close to the proportion observed across the northern circumpolar permafrost region. The large carbon pool size together with significant permafrost thawing suggests a risk of carbon emissions and positive climate feedback across the Tibetan alpine permafrost region. C1 [Ding, Jinzhi; Li, Fei; Yang, Guibiao; Chen, Leiyi; Zhang, Beibei; Liu, Li; Fang, Kai; Qin, Shuqi; Chen, Yongliang; Peng, Yunfeng; Yang, Yuanhe] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Ding, Jinzhi; Li, Fei; Yang, Guibiao; Liu, Li; Fang, Kai; Qin, Shuqi] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Beibei] Inner Mongolia Univ Technol, Hohhot 010051, Inner Mongolia, Peoples R China. [Ji, Chengjun] Peking Univ, Dept Ecol, Beijing 100871, Peoples R China. [Ji, Chengjun] Peking Univ, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China. [He, Honglin] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Smith, Pete] Univ Aberdeen, Inst Biol & Environm Sci, Aberdeen AB24 3UU, Scotland. RP Yang, YH (通讯作者)，Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. EM yhyang@ibcas.ac.cn TC 144 Z9 160 PD AUG PY 2016 VL 22 IS 8 BP 2688 EP 2701 DI 10.1111/gcb.13257 UT WOS:000380016800005 DA 2023-03-23 ER PT J AU Dai, GH Zhu, SS Liu, ZG Chen, LT He, JS Feng, XJ AF Dai GuoHua Zhu ShanShan Liu ZongGuang Chen LiTong He JinSheng Feng XiaoJuan TI Distribution of fatty acids in the alpine grassland soils of the Qinghai-Tibetan Plateau SO SCIENCE CHINA-EARTH SCIENCES DT Article AB As an important biomarker, fatty acids (FAs) have been extensively used to trace the origin of organic matter in sediments and soils. However, studies of the distribution and abundance of FAs in alpine grassland soils are still rare, especially on the Qinghai-Tibetan Plateau (QTP), the highest plateau in the world, which contributes sediments to many large rivers in Asia. This study investigates the composition, distribution and source of FAs with increasing soil depths from 17 typical alpine grassland sites in the QTP. The most abundant FAs included the ubiquitous C-16 FA and even-numbered long-chain FAs (C-20-C-30), indicating mixed inputs from microbial and higher plant sources. Source apportionment showed that higher plants were the dominant contributor of FAs (approximately 40%) in QTP soils. The abundance of FAs decreased with soil depth, with the highest value (1.08 +/- 0.09 mg/g OC) at a 0-10 cm depth and the lowest value (0.46 +/- 0.12 mg/g OC) at a 50-70 cm depth, due to much lower plant inputs into the deeper horizons. The total concentration of FAs was negatively correlated to the mean annual temperature (MAT; P < 0.05) and soil pH (P < 0.01), suggesting that the preservation of FAs was favored in low-MAT and low-pH soils on the QTP. The abundance of fresh OC source FAs increased significantly with the mean annual precipitation (MAP; P < 0.05), indicating that high MAP facilitates the accumulation of fresh FAs in QTP soils. Other environmental parameters, such as the soil mineral content (aluminum and iron oxide), microbial community composition as well as litter quality and quantity, may also exert a strong control on the preservation of FAs in QTP soils and warrant further research to better understand the mechanisms responsible for the preservation of FAs in QTP soils. C1 [Dai GuoHua; Zhu ShanShan; Liu ZongGuang; Feng XiaoJuan] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Chen LiTong; He JinSheng] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [He JinSheng] Peking Univ, Dept Ecol, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. RP Feng, XJ (通讯作者)，Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. EM xfeng@ibcas.ac.cn TC 2 Z9 2 PD JUL PY 2016 VL 59 IS 7 BP 1329 EP 1338 DI 10.1007/s11430-016-5271-2 UT WOS:000379345900002 DA 2023-03-23 ER PT J AU Liu, X Lyu, SM Zhou, SR Bradshaw, CJA AF Liu, Xiang Lyu, Shengman Zhou, Shurong Bradshaw, Corey J. A. TI Warming and fertilization alter the dilution effect of host diversity on disease severity SO ECOLOGY DT Article AB An essential ecosystem service is the dilution effect of biodiversity on disease severity, yet we do not fully understand how this relationship might change with continued climate warming and ecosystem degradation. We designed removal experiments in natural assemblages of Tibetan alpine meadow vegetation by manipulating plot-level plant diversity to investigate the relationship between different plant biodiversity indices and foliar fungal pathogen infection, and how artificial fertilization and warming affect this relationship. Although pathogen group diversity increased with host species richness, disease severity decreased as host diversity rose (dilution effect). The dilution effect of phylogenetic diversity on disease held across different levels of host species richness (and equal abundances), meaning that the effect arises mainly in association with enhanced diversity itself rather than from shifting abundances. However, the dilution effect was weakened by fertilization. Among indices, phylogenetic diversity was the most parsimonious predictor of infection severity. Experimental warming and fertilization shifted species richness to the most supported predictor. Compared to planting experiments where artificial communities are constructed from scratch, our removal experiment in natural communities more realistically demonstrate that increasing perturbation adjusts natural community resistance to disease severity. C1 [Liu, Xiang; Lyu, Shengman; Zhou, Shurong] Fudan Univ, Minist Educ, Key Lab Biodivers Sci & Ecol Engn, Sch Life Sci, Shanghai 200438, Peoples R China. [Bradshaw, Corey J. A.] Univ Adelaide, Sch Biol Sci, Adelaide, SA 5005, Australia. RP Zhou, SR (通讯作者)，Fudan Univ, Minist Educ, Key Lab Biodivers Sci & Ecol Engn, Sch Life Sci, Shanghai 200438, Peoples R China. EM zhshrong@fudan.edu.cn TC 57 Z9 60 PD JUL PY 2016 VL 97 IS 7 BP 1680 EP 1689 DI 10.1890/15-1784.1 UT WOS:000379323800006 DA 2023-03-23 ER PT J AU Xu, HJ Wang, XP Zhang, XX AF Xu, Hao-jie Wang, Xin-ping Zhang, Xiao-xiao TI Alpine grasslands response to climatic factors and anthropogenic activities on the Tibetan Plateau from 2000 to 2012 SO ECOLOGICAL ENGINEERING DT Article AB To address pasture degradation on the Tibetan Plateau, the Chinese government has launched the ecological restoration project Grazing Withdrawal Program (GWP) since 2004. However, few studies have evaluated the impact of the GWP on grassland recovery. Based on monthly remote-sensed vegetation index and meteorological data from 2000 to 2012, we assessed the dynamics of annual net primary productivity (NPP) in alpine grasslands and quantified the effects of climatic factors and anthropogenic activities on NPP change by using the climate-driven NPP and the Carnegie-Ames-Stanford Approach (CASA) models. We found that there existed two distinct periods with an accelerating trend in NPP increase before and after 2004. The area percentage of NPP change induced by climatic factors increased from 41.55% to 83.75%, but that percentage caused by human activities decreased from 58.45% to 16.25% in the two periods of 2000-2004 and 2004-2012. Between 2000 and 2004, overgrazing reduced the positive effect of climate change on NPP variability, resulting in wide-scale grassland degradation. Between 2004 and 2012, grassland ecosystems gradually recovered from heavy grazing pressure, and the human induced degradation was reversed after the implementation of the GWP. Thus, temperature and solar radiation became dominant factors in driving NPP change. Our results indicated that the GWP produces a significant positive effect on the restoration of alpine grasslands by controlling livestock numbers and decreasing grazing intensity. This study provides an objective assessment of restoration actuation on grassland ecosystems, having important implications for demonstrating the effectiveness of the GWP on grassland restoration on the Tibetan Plateau. (C) 2016 Elsevier B.V. All rights reserved. C1 [Xu, Hao-jie; Wang, Xin-ping] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Shapotou Desert Res & Expt Stn, Lanzhou 730000, Peoples R China. [Xu, Hao-jie] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Xiao-xiao] Lanzhou Univ, Sch Phys Sci & Technol, Lanzhou 730000, Peoples R China. RP Wang, XP (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Shapotou Desert Res & Expt Stn, Lanzhou 730000, Peoples R China. EM xpwang@lzb.ac.cn TC 103 Z9 127 PD JUL PY 2016 VL 92 BP 251 EP 259 DI 10.1016/j.ecoleng.2016.04.005 UT WOS:000376732000030 DA 2023-03-23 ER PT J AU Zhu, JT Zhang, YJ Wang, WF AF Zhu, Juntao Zhang, Yangjian Wang, Wenfeng TI Interactions between warming and soil moisture increase overlap in reproductive phenology among species in an alpine meadow SO BIOLOGY LETTERS DT Article AB Climate warming strongly influences reproductive phenology of plants in alpine and Arctic ecosystems. Here, we focus on phenological shifts caused by experimental warming in a typical alpine meadow on the Tibetan Plateau. Under soil water stress caused by warming, most plants in the alpine meadow advanced or delayed their reproductive events to be aligned with the timing of peak rainfall. As a result, warming significantly increased the temporal overlap among reproductive stages of early- and late-flowering species. In addition, we found that some species, for example the late-flowering species, were unable to produce flowers and fruits under warming with failed monsoon rains. The potentially warmer- and drier-growing seasons under climate change may similarly shift the phenological patterns and change species composition of these alpine systems. C1 [Zhu, Juntao; Zhang, Yangjian] Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Zhang, Yangjian] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Wang, Wenfeng] Tibet Acad Agr & Anim Husb Sci, Inst Agr Sci, Lhasa 850032, Peoples R China. RP Zhu, JT; Zhang, YJ (通讯作者)，Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China.; Zhang, YJ (通讯作者)，CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. EM zhujt@igsnrr.ac.cn; zhangyj@igsnrr.ac.cn TC 32 Z9 36 PD JUL PY 2016 VL 12 IS 7 AR 20150749 DI 10.1098/rsbl.2015.0749 UT WOS:000382423700012 DA 2023-03-23 ER PT J AU Ganjurjav, H Gao, QZ Gornish, ES Schwartz, MW Liang, Y Cao, XJ Zhang, WN Zhang, Y Li, WH Wan, YF Li, Y Danjiu, LB Guo, HB Lin, ED AF Ganjurjav, Hasbagan Gao, Qingzhu Gornish, Elise S. Schwartz, Mark W. Liang, Yan Cao, Xujuan Zhang, Weina Zhang, Yong Li, Wenhan Wan, Yunfan Li, Yue Danjiu, Luobu Guo, Hongbao Lin, Erda TI Differential response of alpine steppe and alpine meadow to climate warming in the central Qinghai-Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Recently, the Qinghai-Tibetan Plateau has experienced significant warming. Climate warming is expected to have profound effects on plant community productivity and composition, which can drive ecosystem structure and function. To explore effects of warming on plant community productivity and composition, we conducted a warming experiment using open top chambers (OTCs) from 2012 to 2014 in alpine meadow and alpine steppe habitat on the central Qinghai-Tibetan Plateau. We measured above-ground net primary productivity (ANPP), community composition and species diversity under ambient and two levels of artificially warmed conditions across three years. Our results showed that warming significantly stimulated plant growth in the alpine meadow, but reduced growth on the alpine steppe. The increase of ANPP in alpine meadow was a result of an increase of plant height under warming. Warming-induced drought conditions were primarily responsible for the observed decrease of ANPP in an alpine steppe. Plant community composition and species diversity were not influenced by warming in alpine meadow. Alternatively, in alpine steppe, cover of graminoids and forbs significantly declined while legumes substantially increased under warming, subsequently resulting in rapid species losses. Changes in soil moisture were responsible for observed changes in graminoids and legumes in the alpine steppe. Overall, experimental results demonstrated that warming had a positive impact on plant community structure and function in alpine meadow and had a negative impact on these characteristics in an alpine steppe. This work highlights the important role of soil moisture for regulating plant productivity and community composition response to warming in the alpine steppe. In particular, the deep-rooted, drought resistant plants may increase in a warmer future in the central Qinghai-Tibetan Plateau. These changes may reduce habitat quality for the local community of grazers because many of the species that increased are also unpalatable to grazers. (C) 2016 Elsevier B.V. All rights reserved. C1 [Ganjurjav, Hasbagan; Gao, Qingzhu; Liang, Yan; Cao, Xujuan; Zhang, Weina; Li, Wenhan; Wan, Yunfan; Li, Yue; Lin, Erda] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, CAAS 12 South St Zhongguancun, Beijing 100081, Peoples R China. [Ganjurjav, Hasbagan; Gao, Qingzhu; Liang, Yan; Cao, Xujuan; Zhang, Weina; Li, Wenhan; Wan, Yunfan; Li, Yue; Lin, Erda] Minist Agr, Key Lab Agroenvironm & Climate Change, Beijing 100081, Peoples R China. [Gornish, Elise S.] Univ Calif Davis, Dept Plant Sci, Davis, CA 95616 USA. [Schwartz, Mark W.] Univ Calif Davis, Inst Environm, Davis, CA 95616 USA. [Zhang, Yong] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Danjiu, Luobu; Guo, Hongbao] Nagqu Agr & Anim Husb Bur, Nagqu 852100, Tibet Autonomou, Peoples R China. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, CAAS 12 South St Zhongguancun, Beijing 100081, Peoples R China. EM gaoqingzhu@caas.cn TC 113 Z9 127 PD JUN 15 PY 2016 VL 223 BP 233 EP 240 DI 10.1016/j.agrformet.2016.03.017 UT WOS:000376835000020 DA 2023-03-23 ER PT J AU Li, H Zhang, F Li, Y Zhao, X Cao, G AF Li, H. Zhang, F. Li, Y. Zhao, X. Cao, G. TI Thirty-year variations of above-ground net primary production and precipitation-use efficiency of an alpine meadow in the north-eastern Qinghai-Tibetan Plateau SO GRASS AND FORAGE SCIENCE DT Article AB Above-ground net primary production (ANPP) and precipitation-use efficiency (PUE) are key factors that can clarify the response of grassland ecosystem carbon and water cycles to ongoing climate change. The variations of ANPP and PUE were analysed based on long-term insitu observations of a species-rich alpine meadow in the north-eastern Qinghai-Tibetan Plateau from 1981 to 2010. ANPP and PUE increased markedly over time. ANPP was significantly controlled by post-growing season length (from 1 September to the end of growing season in the previous year, R-2=031, P<001). Regression trees showed that air temperature during October of the previous year played a predominant role in ANPP annual variations. Results indicated that a strong thermal-lagging effect on ANPP variations was present in the alpine meadow ecosystem. ANPP variations were undetectable during wet, normal and dry years (P=025). Our finding supported the hypothesis that temporal site-specific ANPP variations were less regulated by a single factor. The temporal PUE declined linearly with increasing annual precipitation, and the slope was obviously steeper than that of spatial patterns. More ANPP variability in an alpine meadow under warming conditions might occur via community transition in the north-eastern Qinghai-Tibetan Plateau. C1 [Li, H.; Zhang, F.; Li, Y.; Zhao, X.; Cao, G.] Chinese Acad Sci, Northwest Inst Plateau Biol, Xinning St 23, Xining 810001, Qinghai, Peoples R China. [Li, H.; Zhang, F.; Li, Y.; Zhao, X.; Cao, G.] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Qinghai, Peoples R China. RP Li, Y (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xinning St 23, Xining 810001, Qinghai, Peoples R China. EM ynli@nwipb.cas.cn TC 19 Z9 29 PD JUN PY 2016 VL 71 IS 2 BP 208 EP 218 DI 10.1111/gfs.12165 UT WOS:000376001900004 DA 2023-03-23 ER PT J AU Luan, JW Song, HT Xiang, CH Zhu, D Suolang, D AF Luan, Junwei Song, Hongtao Xiang, Chenghua Zhu, Dan Suolang, Duoerji TI Soil moisture, species composition interact to regulate CO2 and CH4 fluxes in dry meadows on the Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB Alpine meadows on the Tibetan Plateau are important sinks for atmosphere carbon (C). Environmental degradation is transforming the continuous sedge (e.g., Kobresia humilis) meadows into a mosaic of sedge and forb-dominated (e.g., Potentilla leuconota) patches, and this provides an ideal system in which to examine how the change in species composition (from sedge-to forb-dominated) affects the CO2 and CH4 fluxes and their response to environmental change. Net ecosystem CO2 exchange (NEE), ecosystem respiration (R-eco), and methane (CH4) fluxes were measured monthly both in sedge- and forb-dominated patches during the growing seasons of 2011 and 2012. The seasonal variations of NEE (negative values represent net uptake of CO2) were negatively affected by soil water content (SWC) both in the sedge (R = -0.46, P=0.02) and in the forb (R = -0.71, P < 0.001) sites, and the SWC regulated the NEE through exerting influence on gross ecosystem photosynthesis (GEP) (P < 0.001) rather than on R-eco (P>0.1). The CH4 fluxes were positively correlated with SWC for both sedge (R = 0.48, P = 0.016) and forb sites (R = 0.70, P < 0.001). Nevertheless, the CH4 emission can offset only 0.05% of the net C uptake as a result of the increase in SWC. Change in species composition did not affect the rates in NEE, R-eco, and GEP (P > 0.05); however, it led to the NEE of the meadow being more sensitive to SWC change (P=0.042). Change in species composition significantly reduced the CH4 flux (P=0.05), which were attributed to the decrease in soil labile carbon (e.g., microbial biomass carbon) and soil enzymatic activity (e.g., protease and urease). However, it increased the soil moisture sensitivity of CH4 flux (P=0.033). We conclude that the C sink strength of the alpine dry meadow is subject to the change in soil water availability on the Plateau, and the alpine meadow will become more vulnerable to drought with the ongoing spread of forb-dominated patches. Our results highlight the role of species composition in regulating the response of the alpine meadow C cycle to environmental change. (C) 2016 Elsevier B.V. All rights reserved. C1 [Luan, Junwei] Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China. [Song, Hongtao] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. [Xiang, Chenghua] Sichuan Acad Forestry, Chengdu 610081, Peoples R China. [Zhu, Dan] Chinese Acad Sci, Chengdu Inst Biol, Chengdu, Peoples R China. [Suolang, Duoerji] Management Bur Zoige Wetland Nat Reserve, Zoige 624500, Peoples R China. [Luan, Junwei] Mem Univ Newfoundland, Sustainable Resource Management, Grenfell Campus, Corner Brook, ON A2H 5G4, Canada. RP Luan, JW (通讯作者)，Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China.; Luan, JW (通讯作者)，Mem Univ Newfoundland, Sustainable Resource Management, Grenfell Campus, Corner Brook, ON A2H 5G4, Canada. EM junweiluan@gmail.com TC 17 Z9 19 PD JUN PY 2016 VL 91 BP 101 EP 112 DI 10.1016/j.ecoleng.2016.02.012 UT WOS:000374766500014 DA 2023-03-23 ER PT J AU Wang, SY Zhang, Y Lu, SH Su, PX Shang, LY Li, ZG AF Wang, Shaoying Zhang, Yu Lu, Shihua Su, Peixi Shang, Lunyu Li, Zhaoguo TI Biophysical regulation of carbon fluxes over an alpine meadow ecosystem in the eastern Tibetan Plateau SO INTERNATIONAL JOURNAL OF BIOMETEOROLOGY DT Article AB The eddy covariance method was used to measure net ecosystem CO2 exchange (NEE) between atmosphere and an alpine meadow ecosystem in the eastern Tibetan Plateau of China in 2010. Our results show that photosynthesis was reduced under low air temperature (T-a), high vapor pressure deficit (VPD), and medium soil water content (SWC) conditions, when compared to that under other Ta (i.e., medium and high), VPD (i.e., low and medium), and SWC (i.e., low and high) conditions. The apparent temperature sensitivity of ecosystem respiration (Q10) declined with progressing phenology during the growing season and decreased with an increase of soil temperature (T-s) during the non-growing season. Increased ecosystem respiration (R-eco) was measured during spring soil thawing. By the path analysis, Ta, Ts, and VPD were the main control factors of CO2 exchange at 30-min scale in this alpine meadow. Integrated NEE, gross primary production (GPP), and Reco over the measured year were -156.4, 1164.3, and 1007.9 g C m(-2), respectively. Zoige alpine meadow was a medium carbon sink based on published data for grassland ecosystems. C1 [Wang, Shaoying; Zhang, Yu; Lu, Shihua; Su, Peixi; Shang, Lunyu; Li, Zhaoguo] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Inst, Key Lab Land Surface & Climate Change Cold & Arid, Lanzhou 730000, Peoples R China. RP Zhang, Y (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Inst, Key Lab Land Surface & Climate Change Cold & Arid, Lanzhou 730000, Peoples R China. EM yuzhang@lzb.ac.cn TC 20 Z9 27 PD JUN PY 2016 VL 60 IS 6 BP 801 EP 812 DI 10.1007/s00484-015-1074-y UT WOS:000379262000002 DA 2023-03-23 ER PT J AU Wang, ZW Wang, Q Zhao, L Wu, XD Yue, GY Zou, DF Nan, ZT Liu, GY Pang, QQ Fang, HB Wu, TH Shi, JZ Jiao, KQ Zhao, YH Zhang, LL AF Wang Zhi-wei Wang Qian Zhao Lin Wu Xiao-dong Yue Guang-yang Zou De-fu Nan Zhuo-tong Liu Guang-yue Pang Qiang-qiang Fang Hong-bing Wu Tong-hua Shi Jian-zong Jiao Ke-qin Zhao Yong-hua Zhang Le-le TI Mapping the vegetation distribution of the permafrost zone on the Qinghai-Tibet Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB In this paper, an updated vegetation map of the permafrost zone in the Qinghai-Tibet Plateau (QTP) was delineated. The vegetation map model was extracted from vegetation sampling with remote sensing (RS) datasets by decision tree method. The spatial resolution of the map is 1 kmx1 km, and in it the alpine swamp meadow is firstly distinguished in the high-altitude areas. The results showed that the total vegetated area in the permafrost zone of the QTP is 1,201,751 km(2). In the vegetated region, 50,260 km(2) is the areas of alpine swamp meadow, 583,909 km(2) for alpine meadow, 332754 km(2) for alpine steppe, and 234,828 km(2) for alpine desert. This updated vegetation map in permafrost zone of QTP could provide more details about the distribution of alpine vegetation types for studying the vegetation mechanisms in the land surface processes of high altitude areas. C1 [Wang Zhi-wei; Wang Qian] Guizhou Acad Agr Sci, Guizhou Inst Prataculture, Guiyang 330006, Peoples R China. [Wang Zhi-wei; Zhao Lin; Wu Xiao-dong; Yue Guang-yang; Zou De-fu; Nan Zhuo-tong; Liu Guang-yue; Pang Qiang-qiang; Fang Hong-bing; Wu Tong-hua; Shi Jian-zong; Jiao Ke-qin; Zhao Yong-hua; Zhang Le-le] Chinese Acad Sci, Cold & Arid Reg Environm & Engineer Res Inst, State Key Lab Cryosher Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou 730000, Peoples R China. [Wang Zhi-wei; Zou De-fu; Fang Hong-bing; Zhang Le-le] Chinese Acad Sci, Grad Univ, Beijing 10049, Peoples R China. RP Zhao, L (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engineer Res Inst, State Key Lab Cryosher Sci, Cryosphere Res Stn Qinghai Tibet Plateau, Lanzhou 730000, Peoples R China. EM wzw1206@163.com; snoopy0729@163.com; linzhao@lzb.ac.cn; wxd565@163.com; yuegy@lzb.ac.cn; zoudf09@lzu.edu.cn; nztong@lzb.ac.cn; liuguangyue@lzb.ac.cn; qqpang@lzb.ac.cn; fanghb@mail.lzjtu.cn; thuawu@lzb.ac.cn; shijz@lzb.ac.cn; kqjiao@lzb.ac.cn; zhaoyonghua@lzb.ac.cn; wyy198836@163.com TC 69 Z9 86 PD JUN PY 2016 VL 13 IS 6 BP 1035 EP 1046 DI 10.1007/s11629-015-3485-y UT WOS:000379268300007 DA 2023-03-23 ER PT J AU Dong, JF Cui, XY Wang, SP Wang, F Pang, Z Xu, N Zhao, GQ Wang, SP AF Dong, Junfu Cui, Xiaoyong Wang, Shuping Wang, Fang Pang, Zhe Xu, Ning Zhao, Guoqiang Wang, Shiping TI Changes in Biomass and Quality of Alpine Steppe in Response to N & P Fertilization in the Tibetan Plateau SO PLOS ONE DT Article AB In the alpine steppe zone on the Central Tibetan Plateau, a large amount of area has been degraded due to natural and artificial factors. N & P fertilization is widely accepted to recover degraded pastures in other regions all over the world. However, it is not clear how alpine steppe communities respond to N & P fertilization, and what is the optimal application rate, in the perspective of forage production. To attempt to explore these questions, in July 2013, two fencing sites were designed in Baingoin County with 12 treatments of different levels of nitrogen (N-0: 0; N-1: 7.5 g m(-2) yr(-1); N-2: 15 g m(-2) yr(-1)) & phosphate (P-0: 0; P-1: 7.5 gP(2)O(5) m(-2) yr(-1); P-2: 15 gP(2)O(5) m(-2) yr(-1); P-3: 30 gP(2)O(5) m(-2) yr(-1)). The results indicated N&P addition was capable to ameliorate the quality of the two sites in the Tibetan Plateau steppe. Increasing N application level resulted in significant increment in Gramineae and total biomass in the two sites. P addition significantly improved the quantity of Compositae, total biomass and the biomasss of other species in site II, while it only significantly improved the total biomass in site I. Gramineae was much more sensitive to N-induced changes than P-induced changes, and this indicated N addition was better to ameliorate the quality of plateau steppe than P-induced changes. No strong evidence was found for critical threshold within 15 g N m(-2) yr(-1), and there was decreasing tendency when P addition rate was above 15 g m(-2) yr(-1). N&P has the potential to accelerate soil acidification, which improved the content of available K, likely as a result of nonsignificant correlation between biomass and soil moisture. This work highlights the the tradeoffs that exist in N and P addition in recovering degraded steppe. C1 [Dong, Junfu; Wang, Shuping; Wang, Fang; Xu, Ning; Zhao, Guoqiang] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. [Dong, Junfu; Cui, Xiaoyong; Pang, Zhe] Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. RP Wang, SP (通讯作者)，Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. EM wshuping@ucas.ac.cn TC 16 Z9 22 PD MAY 25 PY 2016 VL 11 IS 5 AR e0156146 DI 10.1371/journal.pone.0156146 UT WOS:000376881700065 DA 2023-03-23 ER PT J AU Chang, XF Bao, XY Wang, SP Zhu, XX Luo, CY Zhang, ZH Wilkes, A AF Chang, Xiaofeng Bao, Xiaoying Wang, Shiping Zhu, Xiaoxue Luo, Caiyun Zhang, Zhenhua Wilkes, Andreas TI Exploring effective sampling design for monitoring soil organic carbon in degraded Tibetan grasslands SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB The effects of climate change and human activities on grassland degradation and soil carbon stocks have become a focus of both research and policy. However, lack of research on appropriate sampling design prevents accurate assessment of soil carbon stocks and stock changes at community and regional scales. Here, we conducted an intensive survey with 1196 sampling sites over an area of 190 km(2) of degraded alpine meadow. Compared to lightly degraded meadow, soil organic carbon (SOC) stocks in moderately, heavily and extremely degraded meadow were reduced by 11.0%, 13.5% and 17.9%, respectively. Our field survey sampling design was overly intensive to estimate SOC status with a tolerable uncertainty of 10%. Power analysis showed that the optimal sampling density to achieve the desired accuracy would be 2, 3, 5 and 7 sites per 10 km2 for lightly, moderately, heavily and extremely degraded meadows, respectively. If a subsequent paired sampling design with the optimum sample size were performed, assuming stock change rates, predicted by experimental and modeling results, we estimate that about 5-10 years would be necessary to detect expected trends in SOC in the top 20 cm soil layer. Our results highlight the utility of conducting preliminary surveys to estimate the appropriate sampling density and avoid wasting resources due to over-sampling, and to estimate the sampling interval required to detect an expected sequestration rate. Future studies will be needed to evaluate spatial and temporal patterns of SOC variability. (C) 2016 Published by Elsevier Ltd. C1 [Chang, Xiaofeng] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, 26 Xinong Rd, Yangling 712100, Peoples R China. [Zhu, Xiaoxue; Luo, Caiyun; Zhang, Zhenhua] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Haibei Alpine Meadow Ecosyst Res Stn, 23 Xinning Rd, Xining 810008, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, 16 Lincui Rd, Beijing 100101, Peoples R China. [Wang, Shiping] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Bao, Xiaoying; Zhu, Xiaoxue] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Wang, Shiping] Tibet Univ, Naqu Integrated Observat & Res Stn Ecol & Environ, Lasa 850012, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lasa 850012, Peoples R China. [Wilkes, Andreas] World Agroforestry Ctr ICRAF, East & Cent Asia Program, 12 Zhongguancun Nan St, Beijing 100081, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. EM wangsp@itpcas.ac.cn TC 8 Z9 10 PD MAY 15 PY 2016 VL 173 BP 121 EP 126 DI 10.1016/j.jenvman.2016.03.010 UT WOS:000374365100013 DA 2023-03-23 ER PT J AU Ma, K Liu, JG Balkovic, J Skalsky, R Azevedo, LB Kraxner, F AF Ma, Kun Liu, Junguo Balkovic, Juraj Skalsky, Rastislav Azevedo, Ligia B. Kraxner, Florian TI Changes in soil organic carbon stocks of wetlands on China's Zoige plateau from 1980 to 2010 SO ECOLOGICAL MODELLING DT Article AB China's Zoige Plateau, located in the northeastern part of the Qinghai-Tibet plateau, has the largest alpine peat wetland in the world. However, little is known about how the soil organic carbon (SOC) stock of these wetlands has been influenced by human activities. In this study, we quantified the changes in the SOC stock in two counties (i.e., Hongyuan and Ruoergai) in the Zoige Plateau wetlands between 1980 and 2010 in response to progressive drainage of the wetlands and increased grazing intensity using the Environmental Policy Integrated Climate (EPIC) model. The results indicate that wetlands accumulate large amounts of SOC (>300 t C ha(-1)) in the upper 1 m of the soil in the study area. Wetland soils sequestered similar to 0.25 t C ha(-1) yr(-1) despite the degradation that has occurred due to drainage and grazing. Drainage was one of the main driving factors for SOC loss in the wetlands. Conversion of wetlands to grassland via drainage since 1980 led to a loss of approximately 4 t C ha(-1) from the SOC stock. On the other hand, grazing might have positive impact on root biomass accumulation, thus enhancing the SOC stock. As estimated by EPIC, more intensive grazing slightly increased the SOC stock. However, grazing is also a reason why wetlands were drained with all the negative effects on the SOC pool. The potential SOC sequestration of intensive grazing was offseted by the negative effect of drainage. The outcomes suggest not only to limit drainage and restore wetland, but also to control grazing which will in turn decrease drainages to sustain the ecosystem service of carbon sequestration provided by the Zoige wetlands. (C) 2016 Elsevier B.V. All rights reserved. C1 [Ma, Kun; Liu, Junguo] Beijing Forestry Univ, Sch Nat Conservat, Beijing 100083, Peoples R China. [Liu, Junguo] South Univ Sci & Technol China, Sch Environm Sci & Engn, Shenzhen 518055, Peoples R China. [Balkovic, Juraj; Skalsky, Rastislav; Azevedo, Ligia B.; Kraxner, Florian] Int Inst Appl Syst Anal, Ecosyst Serv & Management Program, A-2361 Laxenburg, Austria. [Balkovic, Juraj] Comenius Univ, Fac Nat Sci, Dept Soil Sci, Bratislava 84215, Slovakia. RP Liu, JG (通讯作者)，Beijing Forestry Univ, Sch Nat Conservat, Beijing 100083, Peoples R China.; Liu, JG (通讯作者)，South Univ Sci & Technol China, Sch Environm Sci & Engn, Shenzhen 518055, Peoples R China. EM makun920@126.com; junguo.liu@gmail.com; balkovic@iiasa.ac.at; skalsky@iiasa.ac.at; azevedol@iiasa.ac.at; kraxner@iiasa.ac.at TC 28 Z9 36 PD MAY 10 PY 2016 VL 327 BP 18 EP 28 DI 10.1016/j.ecolmodel.2016.01.009 UT WOS:000373546600002 DA 2023-03-23 ER PT J AU Chen, J Zhao, L Sheng, Y Li, J Wu, XD Du, EJ Liu, GY Pang, QQ AF Chen, Ji Zhao, Lin Sheng, Yu Li, Jing Wu, Xiao-dong Du, Er-ji Liu, Guang-yue Pang, Qiang-qiang TI Some characteristics of permafrost and its distribution in the Gaize area on the Qinghai-Tibet Plateau, China SO ARCTIC ANTARCTIC AND ALPINE RESEARCH DT Article AB An investigation of permafrost in the Gaize area in the west Qinghai-Tibet Plateau in China was conducted in October and November of 2010 and 2011. It was found that mean annual ground temperature was >-1 degrees C with a permafrost thickness of <60 m in the widespread alpine steppe below an altitude of 5400 m a.s.l. The active layer thickness was usually deeper than 3 m with a maximum of about 5.7 m. Overall, the ice/water content of the top 15 m of frozen soil was usually <10%. The altitudinal limit of permafrost in the alpine steppe was about 5100, 5000, and 4950 m a.s.l. on south-, eastwest-, and north-facing slopes, respectively. A permafrost map was constructed using the ARCGIS platform and topographic information from the TOPO 30 digital elevation model. Statistical analysis of the map revealed that permafrost is primarily distributed in the hilly/mountainous areas of Gaize, covering 51% of the study area. The area of permafrost in this map is considerably less than in the Permafrost Map of the Qinghai Tibet Plateau drawn in 1996. Further analysis revealed that the large difference between the two maps could be attributed to both errors in the earlier mapping method and permafrost degradation. C1 [Chen, Ji; Zhao, Lin; Sheng, Yu; Li, Jing; Wu, Xiao-dong; Du, Er-ji; Liu, Guang-yue; Pang, Qiang-qiang] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Chen, Ji; Sheng, Yu; Li, Jing] State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. [Chen, Ji] Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Lanzhou 730000, Peoples R China. [Zhao, Lin; Wu, Xiao-dong; Du, Er-ji; Liu, Guang-yue; Pang, Qiang-qiang] Chinese Acad Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, Lanzhou 730000, Peoples R China. RP Chen, J (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China.; Chen, J (通讯作者)，State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China.; Chen, J (通讯作者)，Beiluhe Observat & Res Stn Frozen Soil Engn & Env, Lanzhou 730000, Peoples R China. EM chenji@lzb.ac.cn TC 17 Z9 18 PD MAY PY 2016 VL 48 IS 2 BP 395 EP 409 DI 10.1657/AAAR0014-023 UT WOS:000376226700012 DA 2023-03-23 ER PT J AU Shang, ZH Yang, SH Wang, YL Shi, JJ Ding, LM Long, RJ AF Shang, Zhanhuan Yang, Shihai Wang, Yanlong Shi, Jianjun Ding, Luming Long, Ruijun TI Soil seed bank and its relation with above-ground vegetation along the degraded gradients of alpine meadow SO ECOLOGICAL ENGINEERING DT Article AB Degradation of alpine meadow may change the composition and size of the soil seed bank, which will impact on the seed bank's capacity for restoration. Four plots were selected to represent the degradation gradients of alpine meadow on Tibetan plateau, namely normal meadow, lightly-degraded meadow, moderately-degraded meadow, and severely-degraded meadow. Soil cores were collected in two seasons, November of 2004 (after seed dispersal) and April of 2005 (before seedling emergence). Soil seed banks were examined by a seedling emergence method. Totals of 56 and 57 species were identified from soil seed bank of four plots in November and April, respectively. The mean size of the soil seed bank on the four plots varied between 2662 and 8026 seeds m-2 in November, and between 3744 and 9773 seeds m-2 in April. The difference in soil seed bank size between the two sampling times (November and April) was not significant within plots. Soil seed banks and above-ground vegetation presented the same trend with vegetation succession across the differently degraded meadows. In all plots, hemicryptophytes accounted for the majority of species and produced the largest number of seeds, of which the majority was weeds. In degraded meadows, the significant increase in weeds (species richness, plant density) changed species composition of soil seed bank and above-ground vegetation along degrading trend. The soil seed bank has important implications for vegetation succession and the restoration of species-diverse alpine meadow on the Tibetan plateau. (C) 2016 Elsevier B.V. All rights reserved. C1 [Shang, Zhanhuan; Ding, Luming; Long, Ruijun] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agro Ecosyst, Lanzhou 730000, Peoples R China. [Yang, Shihai] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. [Wang, Yanlong; Shi, Jianjun] Qinghai Acad Anim & Vet Sci, Inst Grassland Sci, Xining 810003, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agro Ecosyst, Lanzhou 730000, Peoples R China. EM shangzhh@lzu.edu.cn TC 38 Z9 43 PD MAY PY 2016 VL 90 BP 268 EP 277 DI 10.1016/j.ecoleng.2016.01.067 UT WOS:000373376700033 DA 2023-03-23 ER PT J AU Li, Q Chen, DD Zhao, L Yang, X Xu, SX Zhao, XQ AF Li, Qi Chen, Dongdong Zhao, Liang Yang, Xue Xu, Shixiao Zhao, Xinquan TI More than a century of Grain for Green Program is expected to restore soil carbon stock on alpine grassland revealed by field C-13 pulse labeling SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB Anthropogenic changes in land use/cover have altered the vegetation, soil, and carbon (C) cycling on the Qinghai-Tibetan Plateau (QTP) over the last similar to 50 years. As a result, the Grain for Green Program (GfGP) has been widely implemented over the last 10 years to mitigate the impacts of cultivation. To quantify the effects of the GfGP on C partitioning and turnover rates at the ecosystem scale, an in situ C-13 pulse labeling experiment was conducted on natural and GfGP grasslands in an agro-pastoral ecotone in the LakeQinghai region on the QTP. Wefound that there were significant differences in the C stocks of all the considered pools in both the natural and GfGP grasslands, with higher CO2 uptake rates in the GfGP grassland than that in the natural grassland. Partitioning of photoassimilate (% of recovered C-13) in C pools of both grasslands was similar 25 days after labeling, except in the roots of the 0-15 and 5-15 cm soil layer. Soil organic C (SOC) sequestration rate in the GfGP grasslandwas 11.59 +/- 1.89 g C m(-2) yr(-1) significantly greater than that in the natural grassland. The results confirmed that the GfGP is an efficient approach for grassland restoration and C sequestration. However, it will take more than a century (119.19 +/- 20.26 yr) to restore the SOC stock from the current cropland baseline level to the approximate level of natural grassland. We suggest that additional measures are needed in the selection of suitable plant species for vegetation restoration, and in reasonable grazing management. (C) 2016 Elsevier B.V. All rights reserved. C1 [Li, Qi; Chen, Dongdong; Zhao, Liang; Xu, Shixiao; Zhao, Xinquan] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Qinghai, Peoples R China. [Yang, Xue] Dept Educ Qinghai Prov, Xining 810008, Qinghai, Peoples R China. [Zhao, Xinquan] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 10041, Sichuan, Peoples R China. RP Zhao, XQ (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810001, Qinghai, Peoples R China. EM xqzhao@nwipb.cas.cn TC 17 Z9 19 PD APR 15 PY 2016 VL 550 BP 17 EP 26 DI 10.1016/j.scitotenv.2016.01.060 UT WOS:000371226700003 DA 2023-03-23 ER PT J AU Li, YM Wang, SP Jiang, LL Zhang, LR Cui, SJ Meng, FD Wang, Q Li, XN Zhou, Y AF Li, Yaoming Wang, Shiping Jiang, Lili Zhang, Lirong Cui, Shujuan Meng, Fandong Wang, Qi Li, Xine Zhou, Yang TI Changes of soil microbial community under different degraded gradients of alpine meadow SO AGRICULTURE ECOSYSTEMS & ENVIRONMENT DT Article AB Changes in soil bacterial and fungal composition and their diversity with degradation degrees (i.e. non degraded (ND), moderately degraded (MD) and severely degraded (SD) meadows) were investigated in a Tibetan alpine meadow using the Illumina MiSeq. Proteobacteria,Actinobacteria, and Acidobacteria were predominant bacteria in the studied meadow soils, regardless of degradation. ND and MD exhibited no significant differences in bacterial species composition and diversity, while SD significantly altered bacterial composition and increased their diversity compared with ND and MD. Sordariomycetes was predominant fungal class in ND, however, a shift in the fungal class from it to Dothideomycetes was found with increasing degradation level. Moreover, SD apparently increased the relative abundance of pathogenic fungi compared with ND. Degradation significantly shifted fungal species composition and increased their diversity. Soil nutrient conditions could explain 33.8 and 35.6% of the variance in bacterial and fungal composition, respectively. In addition, 25.3 and 21.7% of the variance in bacterial and fungal composition, respectively, were explained by plant properties. However, neither bacterial nor fungal diversity paralleled plant diversity with degradation. Soil silt to sand ratio was the best predictor of shifts in bacterial a -diversity with degradation degrees (R-2> 0.46), while fungal a -diversity was most closely associated with changes in soil available potassium (R-2>0.66). Together, these results suggest that changes of microbial diversity and plant diversity was decoupled under degradation process, and degradation could increase the potential risk of plant diseases and decrease health of the alpine ecosystem. (C) 2016 Elsevier B.V. All rights reserved. C1 [Li, Yaoming; Wang, Shiping; Jiang, Lili; Zhang, Lirong; Cui, Shujuan; Meng, Fandong; Wang, Qi; Li, Xine; Zhou, Yang] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. [Wang, Shiping] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. RP Li, YM; Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China.; Wang, SP (通讯作者)，CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. EM liyaoming@itpcas.ac.cn; wangsp@itpcas.ac.cn TC 82 Z9 108 PD APR 15 PY 2016 VL 222 BP 213 EP 222 DI 10.1016/j.agee.2016.02.020 UT WOS:000384383600022 DA 2023-03-23 ER PT J AU Cheng, RL Yu, YX Liu, LX Zhang, CX Fang, CX AF Cheng, Ruo-Lin Yu, Yong-Xin Liu, Ling-Xiao Zhang, Chuan-Xi Fang, Cheng-Xiang TI A draft genome of the ghost moth, Thitarodes (Hepialus) sp., a medicinal caterpillar fungus SO INSECT SCIENCE DT Letter C1 [Cheng, Ruo-Lin; Zhang, Chuan-Xi] Zhejiang Univ, Inst Insect Sci, Hangzhou 310003, Zhejiang, Peoples R China. [Cheng, Ruo-Lin; Yu, Yong-Xin; Liu, Ling-Xiao; Fang, Cheng-Xiang] Biol Proc Sci & Technol Co Ltd, Chengdu, Peoples R China. RP Zhang, CX (通讯作者)，Zhejiang Univ, Inst Insect Sci, Hangzhou 310003, Zhejiang, Peoples R China.; Fang, CX (通讯作者)，Biol Proc Sci & Technol Co Ltd, Chengdu, Peoples R China. EM chxzhang@zju.edu.cn; cxfang@whu.edu.cn TC 5 Z9 5 PD APR PY 2016 VL 23 IS 2 BP 326 EP 329 DI 10.1111/1744-7917.12292 UT WOS:000373010300017 DA 2023-03-23 ER PT J AU Cheng, Y Cai, YJ Wang, SQ AF Cheng, Yi Cai, Yanjiang Wang, Shen-qiang TI Yak and Tibetan sheep dung return enhance soil N supply and retention in two alpine grasslands in the Qinghai-Tibetan Plateau SO BIOLOGY AND FERTILITY OF SOILS DT Article AB Yak and Tibetan sheep grazing is a common phenomenon on natural grasslands in the Qinghai-Tibetan Plateau, and large amounts of excrement are directly deposited onto alpine grasslands. However, little is known about the effects of excrement return on soil N supply and N retention capacity. This study investigated the short-term effects of yak and Tibetan sheep dung on gross N transformation rates determined by N-15 tracing technique of alpine steppe (AS) and meadow (AM) soils at 60 % water holding capacity (WHC) under laboratory conditions. Cumulative gross N mineralization and NH4 (+) immobilization over the 21-day incubation period in AM soil were around 2.8 and 2.0 times as high as that in AS soil, respectively. Cumulative gross nitrification in AM soil was 0.96 times higher, while the value of gross NO3 (-) immobilization rate was 0.65 times lower than in AS soil, resulting in higher NO3 (-) accumulation in AM soil. Dung addition increased soil gross N mineralization and NH4 (+) immobilization rates by 12-35 % and 17-59 %, respectively. Amending yak and sheep dung decreased gross nitrification rates by 3-23 % but increased gross NO3 (-) immobilization rates by 25-190 %, which led to a decreased net NO3 (-) accumulation and NO3 (-) losses risk through leaching. The cumulative CO2 emissions over the 21 days of incubation period were enhanced by 65 and 120 % for AS and AM soil, respectively. The application of dung stimulated cumulative N2O emissions, but the stimulation was only significant in AM soil. In general, yak and sheep dung return has a positive effect on soil N supply and retention owing to the increase in NH4 (+) availability for plant with simultaneously decreasing NO3 (-) accumulation in soils. C1 [Cheng, Yi; Wang, Shen-qiang] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Jiangsu, Peoples R China. [Cai, Yanjiang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. RP Wang, SQ (通讯作者)，Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Jiangsu, Peoples R China. EM sqwang@issas.ac.cn TC 12 Z9 16 PD APR PY 2016 VL 52 IS 3 BP 413 EP 422 DI 10.1007/s00374-016-1088-6 UT WOS:000373441700013 DA 2023-03-23 ER PT J AU Jia, QH Sun, Q Xie, MM Shan, YB Ling, Y Zhu, QZ Tian, MZ AF Jia Qiuhuan Sun Qing Xie Manman Shan Yabing Ling Yuan Zhu Qingzeng Tian Mingzhong TI Normal Alkane Distributions in Soil Samples along a Lhasa-Bharatpur Transect SO ACTA GEOLOGICA SINICA-ENGLISH EDITION DT Article AB We present n-alkane distributions in the soil samples along a transect from Lhasa on the Tibetan Plateau to Bharatpur in Nepal, which covers a large geographical area and a wide range of climatic conditions. These data allow us to assess the significance of n-alkane distributions in different vegetation types and their relationships to temperature and precipitation. In the tropical rainforest and broadleaved forest zones, n-alkanes exhibit a bimodal distribution pattern with dominant homologues around n-C-31 and n-C-23. The bimodal distribution of tropical rainforest n-alkanes may be a general pattern because of the presence of many lianas, epiphytic plants, algae and the strong microbial activity and degradation involved in the postdepositional process. In the warm-temperate mixed forest and needle-leaved forest zones, the long-chain alkanes have a pattern of n-C-31 > n-C-33 >> n-C-27. In the alpine shrub and grassland zone, although the most abundant homologue is n-C-31, relatively high n-C-23 concentrations have also been observed in some samples. The statistical results show a good correlation between n-alkane proxies and climatic factors. The average chain length (ACL) values are positively correlated with precipitation and temperature across the transect. The carbon preference index (CPI) values show a negative correlation with temperature and precipitation along a Lhasa-Bharatpur transect. Although there is a positive relationship between ACL and temperature, it is difficult to separate the two climatic variables (temperature and precipitation) because they are well coupled in the monsoon region. C1 [Jia Qiuhuan; Tian Mingzhong] China Univ Geosci, Sch Earth Sci & Resources, Beijing 100083, Peoples R China. [Jia Qiuhuan; Sun Qing; Xie Manman; Shan Yabing; Ling Yuan] Natl Res Ctr Geoanal, Beijing 100037, Peoples R China. [Zhu Qingzeng] Chinese Acad Sci, Inst Geol & Geophys, Key Lab Cenozo Geol & Environm, Beijing 100029, Peoples R China. RP Sun, Q (通讯作者)，Natl Res Ctr Geoanal, Beijing 100037, Peoples R China. EM sunqing1616@yahoo.com TC 8 Z9 9 PD APR PY 2016 VL 90 IS 2 BP 738 EP 748 DI 10.1111/1755-6724.12701 UT WOS:000374705600022 DA 2023-03-23 ER PT J AU Feng, JL Hu, HP Chen, F AF Feng, Jin-Liang Hu, Hai-Ping Chen, Feng TI An eolian deposit-buried soil sequence in an alpine soil on the northern Tibetan Plateau: Implications for climate change and carbon sequestration SO GEODERMA DT Article AB The accumulation of eolian dust plays an important role in the development of alpine soils on the northern Tibetan Plateau. However, little is known either about the nature of soil-forming processes in the region, or about the magnitude of soil organic and inorganic carbon (SOC and SIC) storage. Here we report the results of an investigation of a typical profile, consisting of a series of buried soils developed within eolian deposits, situated at an altitude of 4951 m in the Amdo zone of the northern Tibetan Plateau. Bulk density, pH, SOC and SIC content, grain-size distribution, magnetic susceptibility and mineralogical composition were measured at high resolution, and AMS C-14 dating was used to provide a chronology. Based on all of the analytical data we conclude that this alpine accretionary soil profile contains three buried soils beneath the present surface soil layer. The deepest and oldest soil is the basal paleo-weathering crust (Ferralsol) which underwent active soil formation from 5540 to 7615 yr. BP, or even earlier. The other soils, which are developed within the overlying eolian dust deposits, are Luvisols and they document the occurrence of two intervals of more humid conditions than the present day: from similar to 3455 to 5540 yr. cal BP and from similar to 2000-2500 yr. cal BP. Microscopic analysis of coarse particles from the profile reveals that high values of magnetic susceptibility at the base of the profile reflect the presence of coarse magnetite grains present as inclusions within quartz grains derived from the weathering of granitic gneiss. In addition, the magnetic susceptibility profile reflects the effects of winnowing of the eolian fraction by wind activity, and not the production of fine magnetic grains during pedogenesis. SOC is the dominant form of carbon in this alpine soil and the SOC density and average accumulation rate values within the entire interval of eolian deposits are 19.67 kg C m(-2) and 3.55 g C m(-2) yr.(-1), respectively. These remarkably high values indicate that this alpine accretionary soil is characterized by highly efficient SOC burial, and therefore that such soils are an important terrestrial CO2 sink. Likewise, the buried soil plays an important role in SOC storage. Finally, the characteristics of the buried soils indicate a long-term climatic trend towards aridity in the study region. This natural trend has promoted the processes of desertification and grassland degradation on the northern Tibetan Plateau, and these processes may have been exacerbated by human activity. (C) 2015 Elsevier B.V. All rights reserved. C1 [Feng, Jin-Liang; Hu, Hai-Ping; Chen, Feng] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100101, Peoples R China. [Hu, Hai-Ping; Chen, Feng] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Feng, JL (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Bldg 3,16th Lincui Rd, Beijing 100101, Peoples R China. EM fengjl@itpcas.ac.cn TC 9 Z9 10 PD MAR 15 PY 2016 VL 266 BP 14 EP 24 DI 10.1016/j.geoderma.2015.12.005 UT WOS:000369682100002 DA 2023-03-23 ER PT J AU Badingqiuying Smith, AT Senko, J Siladan, MU AF Badingqiuying Smith, Andrew T. Senko, Jesse Siladan, Marcelino U. TI Plateau pika Ochotona curzoniae poisoning campaign reduces carnivore abundance in southern Qinghai, China SO MAMMAL STUDY DT Article AB The plateau pika (Ochotona curzoniae), a small burrowing lagomorph that occupies the high alpine grasslands of the Qinghai-Tibetan Plateau (QTP), has been subject to a massive eradication campaign in China since the late 1950's under the assumption that it promotes grassland degradation. However, mounting evidence suggests that pikas are a keystone species that provide critical ecological services in the alpine meadow ecosystem. Since the implementation of pika control programs, few studies have investigated the potential impacts of pika poisoning on native carnivore species. In 2007 we investigated the impact of pika poisoning on carnivores in southern Qinghai Province, China. Our results show a decrease in the abundance of carnivores from areas where pikas had been poisoned compared with non-poisoned sites, suggesting that the eradication of pikas at regional scales may alter or disrupt ecological communities on the QTP. C1 [Badingqiuying; Smith, Andrew T.; Senko, Jesse] Arizona State Univ, Sch Life Sci, Tempe, AZ 85287 USA. [Siladan, Marcelino U.] Miriam Coll, Coll Arts & Sci, Environm Grad Program, Katipunan Ave 1100, Quezon City 1108, Metro Manila, Philippines. RP Badingqiuying (通讯作者)，Arizona State Univ, Sch Life Sci, Tempe, AZ 85287 USA. EM badingqiuying.xxx@asu.edu TC 21 Z9 26 PD MAR PY 2016 VL 41 IS 1 BP 1 EP 8 UT WOS:000376651400001 DA 2023-03-23 ER PT J AU Deng, BL Li, ZZ Zhang, L Ma, YC Li, Z Zhang, WY Guo, XM Niu, DK Siemann, E AF Deng, Bangliang Li, Zhenzhen Zhang, Ling Ma, Yingchao Li, Zhi Zhang, Wenyuan Guo, Xiaomin Niu, Dekui Siemann, Evan TI Increases in soil CO2 and N2O emissions with warming depend on plant species in restored alpine meadows of Wugong Mountain, China SO JOURNAL OF SOILS AND SEDIMENTS DT Article AB Ecosystem restorations can impact carbon dioxide (CO2) and nitrous oxide (N2O) emissions which are important greenhouse gasses. Alpine meadows are degraded worldwide, but restorations are increasing. Because their soils represent large carbon (C) and nitrogen (N) pools, they may produce significant amounts of CO2 and N2O depending on the plant species used in restorations. In addition, warming and N deposition may impact soil CO2 and N2O emissions from restored meadows. We collected soils from degraded meadows and plots restored using three different plant species at Wugong Mountain (Jiangxi, China). We measured CO2 and N2O emissions when soils were incubated at different temperatures (15, 25 or 35 A degrees C) and levels of N addition (control vs. 4 g m(-2)) to understand their responses to warming and N deposition. Dissolved organic C was higher in restored plots (especially with Fimbristylis dichotoma) compared to non-restored bare soils, and their soil inorganic N was lower. CO2 emission rates were increased by vegetation restorations, decreased by N deposition, and increased by warming. CO2 emission rates were similar for the three grass species at 15 and 25 A degrees C, but they were lower with Miscanthus floridulus at 35 A degrees C. Soils from F. dichotoma and Carex chinensis plots had higher N2O emissions than degraded or M. floridulus plots, especially at 25 A degrees C. These results show that the effects of restorations on soil greenhouse gas emissions depended on plant species. In addition, these differences varied with temperature suggesting that future climate should be considered when choosing plant species in restorations to predict soil CO2 and N2O emissions and global warming potential. C1 [Deng, Bangliang; Li, Zhenzhen; Zhang, Ling; Ma, Yingchao; Li, Zhi; Zhang, Wenyuan; Guo, Xiaomin] Jiangxi Agr Univ, Coll Forestry, Nanchang 330045, Peoples R China. [Niu, Dekui] Jiangxi Agr Univ, Coll Land Resources & Environm, Nanchang 330045, Peoples R China. [Siemann, Evan] Rice Univ, Dept Biosci, Houston, TX 77005 USA. RP Zhang, L (通讯作者)，Jiangxi Agr Univ, Coll Forestry, Nanchang 330045, Peoples R China. EM lingzhang09@126.com TC 35 Z9 45 PD MAR PY 2016 VL 16 IS 3 BP 777 EP 784 DI 10.1007/s11368-015-1307-z UT WOS:000370958100005 DA 2023-03-23 ER PT J AU Zhang, SY Li, XY Zhao, GQ Huang, YM AF Zhang, Si-Yi Li, Xiao-Yan Zhao, Guo-Qin Huang, Yong-Mei TI Surface energy fluxes and controls of evapotranspiration in three alpine ecosystems of Qinghai Lake watershed, NE Qinghai-Tibet Plateau SO ECOHYDROLOGY DT Article AB Qinghai Lake watershed, located in the northeast of the Qinghai-Tibet Plateau, is a region that is sensitive and vulnerable to global climate change. Both the hydrological cycle and water balance in a watershed are significantly influenced by surface energy fluxes and evapotranspiration (ET); however, there is limited information related to the water and heat fluxes in this area. Using the Bowen ratio energy balance method, we measured surface energy fluxes and ET and then explored their controlling factors in three typical ecosystems of the Qinghai Lake watershed, i.e. Kobresia meadow (KMd.), Potentilla fruticosa shrub (PFSh.) and Achnatherum splendens steppe (ASSt.) between 2012 and 2013 for the first time. It was found that between the different ecosystems, there were large differences in the energy portioning. Annual sensible and latent heats accounted for 56-64% and 35-45% of net radiation, respectively. The Bowen rations were the highest in the ASSt. site and the lowest in the PFSh. site. The Bowen ratios and soil water content had negative correlations. Annual ET was 507.9, 493.2 and 413.7mm for the PFSh., KMd. and ASSt. sites, respectively. The annual ET in the KMd. and PFSh. sites was 16% and 3% less than the annual precipitation, while the ET was 26% higher than precipitation for the ASSt. site. Fluctuations in the daily ET of alpine ecosystems from the Qinghai Lake watershed were primarily controlled by radiation, especially during the growing season, whereas ET was also controlled by soil water content in the ASSt. ecosystem where precipitation was low. Copyright (c) 2015 John Wiley & Sons, Ltd. C1 [Zhang, Si-Yi; Li, Xiao-Yan] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Zhang, Si-Yi; Li, Xiao-Yan; Zhao, Guo-Qin; Huang, Yong-Mei] Beijing Normal Univ, Coll Resources Sci & Technol, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. [Zhang, Si-Yi] Guangdong Inst Ecoenvironm & Soil Sci, Guangdong Key Lab Agr Environm Pollut Integrated, Guangzhou 510650, Guangdong, Peoples R China. RP Li, XY (通讯作者)，Beijing Normal Univ, Coll Resources Sci & Technol, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM xyli@bnu.edu.cn TC 35 Z9 38 PD MAR PY 2016 VL 9 IS 2 BP 267 EP 279 DI 10.1002/eco.1633 UT WOS:000372309400007 DA 2023-03-23 ER PT J AU Zhang, Y Dong, SK Gao, QZ Liu, SL Liang, Y Cao, XJ AF Zhang, Yong Dong, Shikui Gao, Qingzhu Liu, Shiliang Liang, Yan Cao, Xujuan TI Responses of alpine vegetation and soils to the disturbance of plateau pika (Ochotona curzoniae) at burrow level on the Qinghai-Tibetan Plateau of China SO ECOLOGICAL ENGINEERING DT Article AB The plateau pika (Ochotona curzoniae) is considered a keystone species on the Qinghai-Tibetan Plateau (QTP). Under a moderate burrow density condition, we investigated plant community and soil properties surrounding pika's burrows in comparison to the control sites (without pika's burrows) in an alpine meadow ecosystem. The results demonstrated that plant biomass, especially aboveground biomass around pika's burrow, was improved. The contents of available soil nutrients around the pika's burrow were improved as well. The highest aboveground biomass and highest contents of NH4-N, available phosphorus and available potassium was detected at the back of the burrow. The compositions of plant community were not changed significantly around the pika burrow, excluding at the front of the burrow. Our findings revealed that the activities of plateau pika can improve the production of alpine meadow and increase the soil fertility at individual burrow level when the burrow density was not out of control. (C) 2015 Elsevier B.V. All rights reserved. C1 [Zhang, Yong; Dong, Shikui; Liu, Shiliang; Cao, Xujuan] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Fernow Hall, Ithaca, NY 14853 USA. [Gao, Qingzhu; Liang, Yan] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China.; Dong, SK (通讯作者)，Beijing Normal Univ, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM dongshikui@sina.com; gaoqzh@ami.ac.cn TC 45 Z9 63 PD MAR PY 2016 VL 88 BP 232 EP 236 DI 10.1016/j.ecoleng.2015.12.034 UT WOS:000369691900022 DA 2023-03-23 ER PT J AU Zhang, YX Min, QW Zhao, GG Jiao, WJ Liu, WW Bijaya, GCD AF Zhang, Yongxun Min, Qingwen Zhao, Guigen Jiao, Wenjun Liu, Weiwei Bijaya, Dhruba G. C. TI Can Clean Energy Policy Improve the Quality of Alpine Grassland Ecosystem? A Scenario Analysis to Influence the Energy Changes in the Three-River Headwater Region, China SO SUSTAINABILITY DT Article; Proceedings Paper CT Sustainable Asia Conference (SAC) CY SEP 20-21, 2015 CL Lanzhou, PEOPLES R CHINA AB In past decades, ecological services and functions of alpine grassland in the Three-River Headwater Region (TRHR), Qinghai-Tibetan Plateau, have been severely degraded due to overgrazing and overuse of yak dung as a fuel. Therefore, the eco-migration project has been implemented by the national government for improving eco-environmental quality in this region. This paper examines the carbon cycle change from clean energy use of households and assesses its influence on the local grassland ecosystem. Based on the data of household fuels from questionnaire surveys and local statistical yearbooks, we have calculated carbon emission and the ecological benefits by using clean energies. The results showed that total carbon in the process from Net Primary Productivity (NPP) of the ecosystem to dung fuel decreases sharply, and carbon emission from dung is approximate 6% of ecosystem NPP. Reducing the use of yak dung as a fuel has no significant influence on carbon emission, but improves the ecological benefits of the grassland ecosystem, because it is a very important part of the ecosystem carbon cycle. With the most abundant solar energy resources in China, the region should make full use of its advantage for improving ecosystem service values of alpine grassland by making more dung returns to grassland. In conclusion, a clean energy policy (CEP) can effectively improve the ecological services and functions of alpine grassland in the TRHR. C1 [Zhang, Yongxun; Min, Qingwen; Zhao, Guigen; Jiao, Wenjun; Liu, Weiwei; Bijaya, Dhruba G. C.] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A,Datun Rd, Beijing 100101, Peoples R China. [Zhang, Yongxun; Zhao, Guigen; Liu, Weiwei; Bijaya, Dhruba G. C.] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Zhang, YX; Zhao, GG (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A,Datun Rd, Beijing 100101, Peoples R China.; Zhang, YX; Zhao, GG (通讯作者)，Univ Chinese Acad Sci, Beijing 100049, Peoples R China. EM zhangyongxun666@163.com; minqw@igsnrr.ac.cn; zhaoguigen@sina.cn; jiaowj1022@163.com; liuww.13b@igsnrr.ac.cn; gc10dhruba@yahoo.com TC 6 Z9 6 PD MAR PY 2016 VL 8 IS 3 AR 231 DI 10.3390/su8030231 UT WOS:000373800600094 DA 2023-03-23 ER PT J AU Li, JZ Liu, YM Mo, CH Wang, L Pang, GW Cao, MM AF Li, Jingzhong Liu, Yongmei Mo, Chonghui Wang, Lei Pang, Guowei Cao, Mingming TI IKONOS Image-Based Extraction of the Distribution Area of Stellera chamaejasme L. in Qilian County of Qinghai Province, China SO REMOTE SENSING DT Article AB Stellera chamaejasme L. (S. chamaejasme) is one of the primary toxic grass species (poisonous plants) distributed in the alpine meadows of Qinghai Province, China. In this study, according to the distinctive phenological characteristics of S. chamaejasme, the spectral differences between S. chamaejasme in the full-bloom stage and other pasture grasses were analyzed and the red, blue, and near-infrared bands of IKONOS image were determined as the diagnostic bands of S. chamaejasme recognition. Feature indexes related to S. chamaejasme were established using the diagnostic bands, and and NDVIblue = (rho(nir) - rho(blue))/(rho(nir) - rho(blue) ) obtained as S. chamaejasme sensitive index based on the linear regression analysis between the indexes derived from field spectra and the actual cover fraction of S. chamaejasme communities. The distribution area of S. chamaejasme was extracted by using the index NDVIblue derived from IKONOS multispectral image in Qilian County of Qinghai Province, China and the verified result reached an overall accuracy of 90.71%. The study indicated that high resolution multispectral satellite images (such as IKONOS images) had significant potential in remote sensing recognition of toxic grass species. C1 [Li, Jingzhong; Liu, Yongmei; Wang, Lei; Pang, Guowei; Cao, Mingming] NW Univ Xian, Coll Urban & Environm Sci, Xian 710127, Peoples R China. [Li, Jingzhong] Xuchang Univ, Coll Urban Planning & Landscape Garden, Xuchang 461000, Peoples R China. [Mo, Chonghui] Qinghai Univ, Agr & Anim Husb Coll, Xining 810016, Peoples R China. RP Liu, YM (通讯作者)，NW Univ Xian, Coll Urban & Environm Sci, Xian 710127, Peoples R China. EM zhong_lij@163.com; liuym@nwu.edu.cn; mchqwhmhg@126.com; montez@nwu.edu.cn; gwpang@126.com; chengshi@nwu.edu.cn TC 6 Z9 11 PD FEB PY 2016 VL 8 IS 2 AR 148 DI 10.3390/rs8020148 UT WOS:000371898800051 DA 2023-03-23 ER PT J AU Li, Q Lu, HY Shen, CM Zhao, Y Ge, QS AF Li, Quan Lu, Houyuan Shen, Caiming Zhao, Yan Ge, Quansheng TI Vegetation successions in response to Holocene climate changes in the central Tibetan Plateau SO JOURNAL OF ARID ENVIRONMENTS DT Article AB Alpine vegetation in the central Tibetan Plateau is vulnerable to climate change. Nine lacustrine pollen records with well-constrained chronologies and high-resolution data were reviewed to document regional and local patterns of alpine vegetation succession in this region, and to understand the climatic driving forces for these changes. According to the relationship between modern pollen distribution and climate condition in the central Tibetan Plateau, Cyperaceae is a moisture-favored and cold-resistant component in both the vegetation and pollen assemblages in the region, while Artemisia is a drought-tolerant and temperate component. Within an east west transect across contemporary alpine steppe zone and alpine meadow zone of the central Tibetan Plateau, Kobresia (Cyperaceae)-dominated alpine meadow expanded westwards to invade the alpine steppe (dominated by Artemisia and Poaceae), and to replace the Artemisia-rich temperate steppe on a regional scale during the mid-Holocene, probably driven by the enhanced precipitation. Vegetation within a south north transect, covered by alpine steppe and temperate steppe, underwent a turnover in steppe composition from a predominance of Artemisia during the first half of the Holocene to a predominance of Cyperaceae in the latter half on a regional scale, caused by a decline in the temperature. Furthermore, altitudinal vegetation belts in the central Tibetan Plateau shifted downwards in response to cooling climate since the early Holocene. Therefore, monsoonal precipitation and insolation-driven temperature changes may be the key climate driving forces for the Holocene vegetation successions in the central Tibetan Plateau. (C) 2015 Elsevier Ltd. All rights reserved. C1 [Li, Quan; Zhao, Yan; Ge, Quansheng] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. [Lu, Houyuan] Chinese Acad Sci, Inst Geol & Geophys, Key Lab Cenozo Geol & Environm, Beijing 100029, Peoples R China. [Shen, Caiming] Yunnan Normal Univ, Coll Tourism & Geog Sci, Kunming 650500, Peoples R China. [Shen, Caiming] SUNY Albany, Atmospher Sci Res Ctr, Albany, NY 12203 USA. RP Li, Q (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Land Surface Pattern & Simulat, Beijing 100101, Peoples R China. EM liquan@igsnrr.cn TC 12 Z9 14 PD FEB PY 2016 VL 125 BP 136 EP 144 DI 10.1016/j.jaridenv.2015.07.010 UT WOS:000366773000019 DA 2023-03-23 ER PT J AU Ma, WM Ding, KY Li, ZW AF Ma, Wenming Ding, Keyi Li, Zhongwu TI Comparison of soil carbon and nitrogen stocks at grazing-excluded and yak grazed alpine meadow sites in Qinghai-Tibetan Plateau, China SO ECOLOGICAL ENGINEERING DT Article AB The effects of yak grazing on C and N below-ground pools were evaluated by comparing five grazing excluded sample site pairs (5 years of grazing exclusion) at the Eastern edge of the Qinghai-Tibetan Plateau. Soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), bulk density, pH and soil particle size fractions were analyzed in these samples taken at a depth of 10 cm. Our results showed TK stock and bulk density had increasing trends with grazing activity. pH presented a slight increase, but the differences were not significant. On the contrary, SOC, TSN and TP stocks declined in grazing plots (P < 0.05) and respectively decreased by 32.9%, 27.4%, and 10.5%, while TK stocks increased by 6.8%. P may become limited elements over time owing to an imbalance of inputs and outputs. Elemental stocks calculated by the equivalent mass method indicated the reported SOC losses based on the conventional method might be overestimated and that sampling depth of 7.64 cm rather than same with sampling depth for grazing-excluded site (10 cm) should be applied for grazing site if conventional method is used to calculate carbon stock. The soil silt content in grazing-excluded sites was greater than that in grazed zones (P < 0.05), whilst greater soil specific surface areas were also found in the grazing excluded sites, indicating that manual fencing led to heterogeneous distribution of soil particles and those silts may play a primary role in nutrient stocks in this region. (C) 2015 Elsevier B.V. All rights reserved. C1 [Ma, Wenming; Ding, Keyi] Southwest Univ Nationalities, South 4th Sect,1st Ring Rd, Chengdu 610041, Peoples R China. [Li, Zhongwu] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China. RP Ma, WM; Ding, KY (通讯作者)，Southwest Univ Nationalities, South 4th Sect,1st Ring Rd, Chengdu 610041, Peoples R China. EM qswghn2013@163.com; keyiding2000@aliyun.com TC 44 Z9 50 PD FEB PY 2016 VL 87 BP 203 EP 211 DI 10.1016/j.ecoleng.2015.11.040 UT WOS:000368899800026 DA 2023-03-23 ER PT J AU Shang, W Wu, XD Zhao, L Yue, GY Zhao, YH Qiao, YP Li, YQ AF Shang, Wen Wu, Xiaodong Zhao, Lin Yue, Guangyang Zhao, Yonghua Qiao, Yongping Li, Yuqiang TI Seasonal variations in labile soil organic matter fractions in permafrost soils with different vegetation types in the central Qinghai-Tibet Plateau SO CATENA DT Article AB Labile soil organic matter (SOM) plays a crucial role in nutrient and carbon cycling, particularly in permafrost ecosystems. Understanding its variation is therefore very important. In the present study, we evaluated the seasonal patterns of labile SOM from April 2013 to March 2014 under alpine swamp meadow (ASM), meadow (AM), steppe (AS) and desert (AD) vegetation in permafrost regions of the China's Qinghai-Tibet Plateau. The fractions (0 to 10 cm depth) included dissolved organic carbon (DOC), light-fraction carbon (LFC) and nitrogen (LFN), and microbial biomass carbon (MBC) and nitrogen (MBN). These fractions showed dramatic seasonal patterns in ASM and AM soils, but were relatively stable in AD soil. Soil DOC concentrations in the ASM, AM, and AD soils increased from April to May 2013, then increased again from July to August 2013 and from February to March 2014. The LFC and LFN concentrations in all four vegetation types were higher from June to August 2013. The highest MBC and MBN concentrations in the ASM, AM, and AS soils all occurred in the summer and the ASM soil showed a second peak in October or November 2013. Seasonal changes in climatic factors, vegetation types, and permafrost features were great causes of labile SOM variations in this study. Throughout the entire sampling period, the ASM soil generally had the highest labile SOM, followed by the AM, AS, and AD soils; thus, the ASM soil is the best system conserving soil nutrient (especially labile fractions) and microbial activity. Correlation analysis indicated that these fractions were not related to soil moisture and temperature in AS or AD soils, but soil temperature and moisture were significantly related to MBC and MBN in AM soil and DOC in ASM soil. Thus, the response of the labile SOM fractions in this high-altitude permafrost soils to climate change depended strongly on vegetation types. (C) 2015 Elsevier B.V. All rights reserved. C1 [Shang, Wen; Wu, Xiaodong; Zhao, Lin; Yue, Guangyang; Zhao, Yonghua; Qiao, Yongping] Chinese Acad Sci, Cryosphere Res Stn Qinghai Xizang Tibet Plateau, State Key Lab Cryospher Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Gansu, Peoples R China. [Shang, Wen] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Li, Yuqiang] Chinese Acad Sci, Naiman Desertificat Res Stn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Gansu, Peoples R China. RP Wu, XD (通讯作者)，320 Donggang West Rd, Lanzhou 730000, Peoples R China. EM wxd565@163.com; linzhao@lzb.ac.cn TC 48 Z9 56 PD FEB PY 2016 VL 137 BP 670 EP 678 DI 10.1016/j.catena.2015.07.012 UT WOS:000367635800066 DA 2023-03-23 ER PT J AU Bosch, A Dorfer, C He, JS Schmidt, K Scholten, T AF Bosch, Anna Doerfer, Corina He, Jin-Sheng Schmidt, Karsten Scholten, Thomas TI Predicting soil respiration for the Qinghai-Tibet Plateau: An empirical comparison of regression models SO PEDOBIOLOGIA DT Article AB Alpine ecosystems like the Qinghai-Tibet Plateau strongly respond to global warming. Their soils, containing large carbon stocks, release more carbon dioxide as a possible consequence. Reciprocally, this may intensify climate warming. The Qinghai-Tibet plateau's large and almost inaccessible terrain results in a general data scarcity for this area making the quantification of soil carbon dynamics challenging. The current study provides an area-wide estimation of soil respiration for the Qinghai-Tibet Plateau, which is a key region for climate change studies due to its size and sensitivity. We compared the ability of six regression models to predict soil respiration that were developed within different studies and are based on mean annual air temperature, mean annual precipitation and belowground biomass. We used the WorldClim data sets to approximate annual soil respiration on a regional scale. Compared to field measurements of soil respiration at single spots in different vegetation zones on the Qinghai-Tibet Plateau (max. 1876.63 g Cm-2 year(-1)), our predicted results (max. 1765.13 g Cm-2 year-1) appear to be consistent. The basic difference between grasslands and forests in soil respiration is indicated by all regression models, however, a more precise differentiation between vegetation types is only exhibited by the regression model based on mean annual precipitation. Overall, this model performs best for most and the largest vegetation zones. Nevertheless, the approximations of the model based on mean annual temperature by Raich and Schlesinger (1992) with a lower constant better represent the vegetation zone of the alpine steppe. With this spatial estimation of soil respiration at a regional scale, a basis for assessing an area-specific potential of greenhouse gas emissions on the Qinghai-Tibet Plateau is provided. Moreover, we quantify a complex soil ecological process for this data-scarce area. (C) 2016 Elsevier GmbH. All rights reserved. C1 [Bosch, Anna; Doerfer, Corina; Schmidt, Karsten; Scholten, Thomas] Univ Tubingen, Dept Geosci, Chair Soil Sci & Geomorphol, Ruemelinstr 19-23, D-72070 Tubingen, Germany. [He, Jin-Sheng] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [He, Jin-Sheng] Peking Univ, Dept Ecol, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. [He, Jin-Sheng] Peking Univ, Minist Educ, Key Lab Earth Surface Proc, Beijing 100871, Peoples R China. RP Bosch, A (通讯作者)，Univ Tubingen, Dept Geosci, Chair Soil Sci & Geomorphol, Ruemelinstr 19-23, D-72070 Tubingen, Germany. EM anna.bosch@geographie.uni-tuebingen.de TC 7 Z9 7 PD JAN PY 2016 VL 59 IS 1-2 BP 41 EP 49 DI 10.1016/j.pedobi.2016.01.002 UT WOS:000372385300006 DA 2023-03-23 ER PT J AU Du, YG Guo, XW Cao, GM Li, YK AF Du, Yangong Guo, Xiaowei Cao, Guangmin Li, Yikang TI Increased Nitrous Oxide Emissions Resulting from Nitrogen Addition and Increased Precipitation in an Alpine Meadow Ecosystem SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES DT Article AB The effects of nitrogen (N) addition and increased precipitation on nitrous oxide (N2O) emissions in alpine meadow ecosystems are still unclear. In this study, we measured N2O fluxes on the Tibetan plateau under interactions of moderate atmospheric N deposition and increased precipitation using a closed chamber method. Under all applied treatment conditions, the alpine meadow ecosystem acted as a source of N2O. The N2O emission rate reached a maximum of 74.83 +/- 14.40 mu g m(-2) h(-1), with a significant increase in emission rate of 68.76% following N addition when compared with the control plot (p<0.05). Increased precipitation, and its interactive combination with N deposition, enhanced the N2O emission rate by 53.90% and 44.52%, respectively. However, there was no significant difference between these two treatments. Increased precipitation would help to mitigate N2O fluxes under global nitrogen deposition conditions. C1 [Du, Yangong] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Du, Yangong; Guo, Xiaowei; Cao, Guangmin; Li, Yikang] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Du, Yangong] Wagga Wagga Agr Inst, NSW Dept Ind Skills & Reg Dev, Wagga Wagga, NSW 2650, Australia. [Guo, Xiaowei] Graham Ctr Agr Innovat, Alliance NSW Dept Ind, Wagga Wagga, NSW 2650, Australia. [Guo, Xiaowei] Charles Start Univ, Wagga Wagga, NSW 2650, Australia. RP Du, YG (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China.; Du, YG (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China.; Du, YG (通讯作者)，Wagga Wagga Agr Inst, NSW Dept Ind Skills & Reg Dev, Wagga Wagga, NSW 2650, Australia. EM ygdu@nwipb.cas.cn TC 8 Z9 12 PY 2016 VL 25 IS 1 BP 447 EP 451 DI 10.15244/pjoes/60860 UT WOS:000369561700048 DA 2023-03-23 ER PT J AU He, SY Richards, K Zhao, ZQ AF He, Siyuan Richards, Keith Zhao, Zhiqiang TI Climate extremes in the Kobresia meadow area of the Qinghai-Tibetan Plateau, 1961-2008 SO ENVIRONMENTAL EARTH SCIENCES DT Article AB The Alpine Kobresia meadow is a major vegetation type on the Qinghai-Tibetan Plateau in western China. It is important both in preserving local and regional water and carbon and as a valuable pasture resource; however, meadow degradation has been spreading under both climatic and human disturbance. Climate extremes and related disasters are more discernible by local people than gradual trends and may have rapid and direct impact on the ecosystem; however, research on the resilience of the Kobresia meadow is rare. This study uses time series of 21 objectively defined indices of daily temperature (12) and precipitation (9) extremes from representative weather stations in the Kobresia meadow region to analyse the spatial pattern and regional trend in climate extremes over the period of 1961-2008. A general tendency towards more warm extremes is found over the Kobresia meadow and is more noticeable at night, although the increase in the warmest daytime temperature is larger than that of the warmest night-time temperature. The meadow region is, however, not experiencing a uniform tendency in terms of precipitation extremes, except for a decrease in consecutive dry days, which seems to occur especially at higher altitudes. Regionally, there seems no obvious trend in rain intensity, but a quasi-decadal fluctuation occurs. The middle and eastern Kobresia meadow area has experienced relatively milder extreme climatic change especially in night-time cold temperatures and in precipitation. Targeted measures towards sustaining the Kobresia meadow need to take these regional differences in climatic extremes into account. C1 [He, Siyuan] Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. [Richards, Keith] Univ Cambridge, Dept Geog, Downing Pl, Cambridge CB2 3EN, England. [Zhao, Zhiqiang] Peking Univ, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. RP He, SY (通讯作者)，Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM siyuan.he@bnu.edu.cn TC 17 Z9 17 PD JAN PY 2016 VL 75 IS 1 AR 60 DI 10.1007/s12665-015-4784-x UT WOS:000370239800060 DA 2023-03-23 ER PT J AU Li, HQ Zhang, FW Mao, SJ Zhu, JB Yang, YS He, HD Li, YN AF Li, Hongqin Zhang, Fawei Mao, Shaojuan Zhu, Jingbin Yang, Yongsheng He, Huidan Li, Yingnian TI Effects of Grazing Exclusion on Soil Properties in Maqin Alpine Meadow, Tibetan Plateau, China SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES DT Article AB Grazing exclusion with fencing has been widely implemented to rehabilitate degraded grasslands in China. However, the response of grassland ecosystems has remained controversial among sites and vegetation types. In this study, characteristics of vegetation and soil properties under degradation gradients (light and middle) and grazing exclusion were examined in the Maqin alpine meadow in August 2013. The results showed that grazing exclusion resulted in a significant recovery in vegetation with higher above-and below-ground biomasses, which reached 459.29 g.m(-2) and 5,657.93 g.m(-2) in comparison with 132.53 g.m(-2) and 1,494.37 g.m(-2) in middle degraded plots, respectively. Soil bulk density in grazing exclusion decreased especially obviously in the 0-10 cm layer. Soil capillary and saturated water in grazing exclusion increased to 1,075.2 g.kg(-1) and 1,072.4 g.kg(-1), respectively, in the 0-10 cm layer. They also increased a little in the 10-20 cm layer. Grazing exclusion had significant positive effects on soil organic carbon and total nitrogen content, especially in the 0-10 cm layer. The results above indicated that grazing exclusion was an effective restoration approach to rehabilitate degraded alpine meadow in Maqin. C1 [Li, Hongqin; Zhang, Fawei; Zhu, Jingbin; Yang, Yongsheng; He, Huidan; Li, Yingnian] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Peoples R China. [Li, Hongqin; Zhang, Fawei; Yang, Yongsheng; Li, Yingnian] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. [Zhu, Jingbin; He, Huidan] Univ Chinese Acad Sci, Beijing, Peoples R China. [Mao, Shaojuan] Qinghai Univ, Xining, Peoples R China. RP Li, YN (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Peoples R China.; Li, YN (通讯作者)，Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, Xining, Peoples R China. EM ynli@nwipb.cas.cn TC 12 Z9 12 PY 2016 VL 25 IS 4 BP 1583 EP 1587 DI 10.15244/pjoes/62099 UT WOS:000381108800021 DA 2023-03-23 ER PT J AU Qin, XJ Sun, J Liu, M Lu, XY AF Qin, Xiaojing Sun, Jian Liu, Miao Lu, Xuyang TI The Impact of Climate Change and Human Activity on Net Primary Production in Tibet SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES DT Article AB The Tibetan Plateau has faced environmental degradation in recent years due to intensified human activity and climate change. In this study, the dynamics of net primary production (NPP), annual mean temperature (AMT), annual mean precipitation (AMP), number of animals (NA), number of rural laborers (NRL), and animal husbandry (AH) were analyzed and the response of NPP to climate and human activity explored. The results show that NPP was increasing gradually from northwest to southeast and is similar to the distribution of AMP. In addition, NA, NRL, and AH cluster around Lhasa. Moreover, AMP had a negative correlation with NPP in Tibet while AMT has a positive effect on NPP. Moreover, because of the large number of livestock there is a negative relationship between NA and NPP in most Tibetan regions. Furthermore, it was found that human activity made a higher contribution to NPP in Tibet (24.73%) than climate factors (17.28%). It is, therefore, necessary to further explore the relationship between human activity and the vegetation dynamic in the region. C1 [Qin, Xiaojing; Lu, Xuyang] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Sun, Jian] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Liu, Miao] Chinese Acad Sci, Res Ctr Ecoenvironm Sci, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China. [Qin, Xiaojing] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Sun, J (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. EM sunjian@igsnmac.cn TC 8 Z9 11 PY 2016 VL 25 IS 5 BP 2113 EP 2120 DI 10.15244/pjoes/62986 UT WOS:000385472400035 DA 2023-03-23 ER PT J AU Wang, DX Gao, YH Wang, P Zeng, XY AF Wang, Dongxue Gao, Yongheng Wang, Ping Zeng, Xiaoyang TI RESPONSES OF CO2 AND N2O EMISSIONS TO CARBON AND PHOSPHORUS ADDITIONS IN TWO CONTRASTING ALPINE MEADOW SOILS ON THE QINGHAI-TIBETAN PLATEAU SO FRESENIUS ENVIRONMENTAL BULLETIN DT Article AB A 45-day incubation experiment in laboratory was conducted to examine the effects of the carbon (C) and phosphorus (P) additions on carbon dioxide (CO2) and nitrous oxide (N2O) emissions from two alpine meadow soils sampled on the Qinghai-Tibetan Plateau: one with acid pH and high organic carbon content (HM), and the other one with alkaline pH and low organic carbon content (CM). The concentrations of DOC, NO3--N, NH4+-N and DTN in soils were measured at the end of the incubation. Addition of C significantly increased soil CO2 and N2O emissions in both alpine meadow soils. No significant effect of P addition on CO2 and N2O emission was detected in both soils. Data analysis revealed a significant positive correlation between the cumulative CO2 emissions and the soil DOC concentration, and a significant negative correlation between the cumulative N2O emissions and soil NO3--N concentration. These results suggest that soil CO2 and N2O emission is directly linked to the availability of soil C, while P is not the limiting factor for soil microbial activity in alpine meadow soils. C1 [Wang, Dongxue; Wang, Ping] Gansu Agr Univ, Coll Resources & Environm, Lanzhou 730070, Peoples R China. [Wang, Dongxue; Gao, Yongheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Zeng, Xiaoyang] Sichuan Coll Architectural Technol, Dept Landscape Architecture, Deyang 610081, Peoples R China. RP Wang, P (通讯作者)，Gansu Agr Univ, Coll Resources & Environm, Lanzhou 730070, Peoples R China. EM ecologist@126.com TC 6 Z9 8 PY 2016 VL 25 IS 10 BP 4401 EP 4408 UT WOS:000386746100069 DA 2023-03-23 ER PT J AU Wu, QB Zhang, ZQ Gao, SR Ma, W AF Wu, Qingbai Zhang, Zhongqiong Gao, Siru Ma, Wei TI Thermal impacts of engineering activities and vegetation layer on permafrost in different alpine ecosystems of the Qinghai-Tibet Plateau, China SO CRYOSPHERE DT Article AB Climate warming and engineering activities have various impacts on the thermal regime of permafrost in alpine ecosystems of the Qinghai-Tibet Plateau. Using recent observations of permafrost thermal regimes along the Qinghai-Tibet highway and railway, the changes of such regimes beneath embankments constructed in alpine meadows and steppes are studied. The results show that alpine meadows on the Qinghai-Tibet Plateau can have a controlling role among engineering construction effects on permafrost beneath embankments. As before railway construction, the artificial permafrost table (APT) beneath embankments is not only affected by climate change and engineering activities but is also controlled by alpine ecosystems. However, the change rate of APT is not dependent on ecosystem type, which is predominantly affected by climate change and engineering activities. Instead, the rate is mainly related to cooling effects of railway ballast and heat absorption effects of asphalt pavement. No large difference between alpine and steppe can be identified regarding the variation of soil temperature beneath embankments, but this difference is readily identified in the variation of mean annual soil temperature with depth. The vegetation layer in alpine meadows has an insulation role among engineering activity effects on permafrost beneath embankments, but this insulation gradually disappears because the layer decays and compresses over time. On the whole, this layer is advantageous for alleviating permafrost temperature rise in the short term, but its effect gradually weakens in the long term. C1 [Wu, Qingbai; Zhang, Zhongqiong; Gao, Siru; Ma, Wei] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Wu, Qingbai; Ma, Wei] Chinese Acad Sci, Beiluhe Observat Stn Frozen Soil Environm & Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Wu, QB (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China.; Wu, QB (通讯作者)，Chinese Acad Sci, Beiluhe Observat Stn Frozen Soil Environm & Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. EM qbwu@lzb.ac.cn TC 43 Z9 46 PY 2016 VL 10 IS 4 BP 1695 EP 1706 DI 10.5194/tc-10-1695-2016 UT WOS:000381218000013 DA 2023-03-23 ER PT J AU Zhu, XX Luo, CY Wang, SP Zhang, ZH Cui, SJ Bao, XY Jiang, LL Li, YM Li, XN Wang, Q Zhou, Y AF Zhu, Xiaoxue Luo, Caiyun Wang, Shiping Zhang, Zhenhua Cui, Shujuan Bao, Xiaoying Jiang, Lili Li, Yaoming Li, Xine Wang, Qi Zhou, Yang TI Effects of warming, grazing/cutting and nitrogen fertilization on greenhouse gas fluxes during growing seasons in an alpine meadow on the Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Increased nitrogen (N) deposition within the context of both warming and grazing is relevant to understand the response of greenhouse gases fluxes (GHG) (i.e. CO2, CH4 and N2O fluxes) for alpine meadow ecosystems to projected changes in the environment. A previous controlled warming and grazing experiment only included no warming with no grazing (NWNG), no warming with grazing (NWG), warming with no grazing (WNG) and warming with grazing (WG) from 2006 to 2010. N fertilization was added to the experimental setup to determine the effects of warming, grazing and N fertilization on GHG fluxes in an alpine meadow on the Tibetan Plateau during the growing seasons from 2010 to 2012. Sheep grazing was utilized during the growing season from 2006 to 2010 and cutting was used as simulation of grazing during the non-growing seasons in 2011 and 2012. Warming significantly increased average seasonal CO2 emission by 10%, and nitrogen addition increased average seasonal CH4 uptake by 14% during the growing seasons in the dry years of 2011 and 2012. Warming increased average seasonal CH4 uptake by 32-46% over the 3-year period, and grazing increased annual average N2O emission by 62% only in 2010. N fertilization alone did not significantly affect CO2 and N2O fluxes during the experimental period. The interactive effects of warming, grazing/cutting and N fertilization effect on daily CH4 or daily N2O flux depended on sampling date. Ecosystem CO2 emission was mainly affected by soil temperature and plant aboveground net primary production (ANPP), which explained about 55% and 18% of its variation. Soil moisture and ANPP could explain 17% and 8% of the variation of CH4 uptake in the region. Our results suggest that the stimulating effect of warming on ecosystem respiration still occurs in 2011 and 2012 after warming for seven years. Moreover, our results imply that moderate grazing/cutting may be preferred compared with no grazing or no cutting because its negative effect on GHG fluxes was small, and interactive effect of warming, grazing/cutting and increased N deposition on GHG emission could be neglected in the alpine meadow. (C) 2015 Elsevier B.V. All rights reserved. C1 [Zhu, Xiaoxue; Luo, Caiyun; Zhang, Zhenhua] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Wang, Shiping; Cui, Shujuan; Jiang, Lili; Li, Yaoming; Li, Xine; Wang, Qi; Zhou, Yang] Chinese Acad Sci, Key Lab Alpine Ecol & Biodivers, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. [Wang, Shiping] CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. [Zhu, Xiaoxue; Cui, Shujuan; Bao, Xiaoying; Wang, Qi; Zhou, Yang] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, Key Lab Alpine Ecol & Biodivers, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. EM wangsp@itpcas.ac.cn TC 73 Z9 85 PD DEC 15 PY 2015 VL 214 BP 506 EP 514 DI 10.1016/j.agrformet.2015.09.008 UT WOS:000364730000045 DA 2023-03-23 ER PT J AU Li, XY Cheng, SL Fang, HJ Yu, GR Dang, XS Xu, MJ Wang, L Si, GY Geng, J He, S AF Li, Xiaoyu Cheng, Shulan Fang, Huajun Yu, Guirui Dang, Xusheng Xu, Minjie Wang, Lei Si, Gaoyue Geng, Jing He, Shun TI The contrasting effects of deposited NH4+ and NO3- on soil CO2, CH4 and N2O fluxes in a subtropical plantation, southern China SO ECOLOGICAL ENGINEERING DT Article AB Background and aims: Deposited NH4+ and NO3- differently affect soil carbon (C) and nitrogen (N) cycles due to their contrasting actions in terrestrial ecosystems. However, little information on the effects of exogenous NH4+ and NO3- inputs on the exchange of greenhouse gases (GHGs) from the subtropical plantation soils as well as their contribution to global warming is available to date. Methods: Based on a field experiment, two-form (NH4Cl and NaNO3) and two-level (40 and 120 kg N ha(-1) yr(-1)) of N addition, in a slash pine plantation of southern China, we investigated soil CO2, CH4 and N2O fluxes and related auxiliary variables (soil temperature and moisture) twice a week using static chamber-gas chromatography. The total global warming potential (GWP) of soil GHG fluxes and N2O emission factor (EF) were calculated. Results: Low level of NaNO3 addition significantly increased cumulative annual soil CO2 emission by 33.7%. N addition significantly promoted annual soil N2O emission by 2.4-6.9 folds; moreover, ammonium-N addition had a greater promotion to soil N2O emission than nitrate-N addition. However, short-term N addition did not change soil CH4 uptake. Also, soil CO2 and N2O fluxes were positively correlated with soil temperature and moisture, while soil CH4 uptake was only driven by soil moisture. Overall, elevated N addition increased the total GWP, and changed the temperature sensitivity (Q(10)) of soil CO2 and N2O fluxes. Conclusions: These results suggest that chronic atmospheric N deposition changes soil-atmospheric GHG fluxes in the subtropical plantation of southern China depending on the levels and forms of N input, and would exacerbate global warming. (C) 2015 Elsevier B.V. All rights reserved. C1 [Li, Xiaoyu; Fang, Huajun; Yu, Guirui; Dang, Xusheng; Wang, Lei; Geng, Jing] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Cheng, Shulan; Xu, Minjie; Si, Gaoyue; He, Shun] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Fang, HJ (通讯作者)，11A Datun Rd, Beijing 100101, Peoples R China. EM slcheng@ucas.ac.cn; fanghj@igsnrr.ac.cn TC 33 Z9 40 PD DEC PY 2015 VL 85 BP 317 EP 327 DI 10.1016/j.ecoleng.2015.10.003 UT WOS:000365322700034 DA 2023-03-23 ER PT J AU Li, HL Nicotra, AB Xu, DH Du, GZ AF Li, Honglin Nicotra, Adrienne B. Xu, Danghui Du, Guozhen TI Habitat-specific responses of leaf traits to soil water conditions in species from a novel alpine swamp meadow community SO CONSERVATION PHYSIOLOGY DT Article AB Species originally from alpine wetland and alpine meadow communities now coexist in a novel 'alpine swamp meadow' community as a consequence of wetland drying in the eastern Tibetan Plateau. Considering the projected increase in the fluctuation of water supply from precipitation during the growing season in this area in the future, it is important to investigate the responses of the species that make up this new community to soil water availability. Using a transplant experimental design, we compared the response of leaf traits and growth to different water conditions for species grouped according to their original habitat of wetland or meadow. Twelve perennial herbaceous species, which form an alpine swamp meadow community in Maqu County in the eastern Tibetan Plateau, were used in this study and subjected to two water treatments, namely waterlogged and dry-down. Overall, significant differences in leaf production in response to soil water availability were found for these two groups, indicating strongly different effects of water availability on their growth. Furthermore, the meadow group had lower specific leaf area, leaf area and relative leaf water content, but thicker leaves than those of the wetland group, indicating significant habitat-specific differences in leaf morphology. Regarding physiological traits, the wetland group had significantly higher photosynthetic rates in inundated conditions, whereas for the meadow group the photosynthetic rate was greatest in cyclically dry conditions. Likewise, a similar pattern was observed for stomatal conductance; however, both groups achieved higher instantaneous water use efficiency during the dry-down treatment. The results of this study indicate that the composition of the alpine swamp meadow could be sensitive to changes in precipitation and might be changed substantially by future declines in water supply, as predicted by global climate change models for this region. This potential for compositional change of the community should be considered when management and conservation decisions are made. C1 [Li, Honglin; Xu, Danghui; Du, Guozhen] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Peoples R China. [Li, Honglin; Nicotra, Adrienne B.] Australian Natl Univ, Res Sch Biol, Canberra, ACT 0200, Australia. RP Du, GZ (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland & Agroecosyst, Lanzhou 730000, Peoples R China. EM guozdu@lzu.edu.cn TC 6 Z9 6 PD NOV 11 PY 2015 VL 3 AR cov046 DI 10.1093/conphys/cov046 UT WOS:000375201400001 DA 2023-03-23 ER PT J AU Shi, SB Shi, R Li, M AF Shi, Sheng-Bo Shi, Rui Li, Miao TI Changes in photosynthesis of alpine plant Saussurea superba during leaf expansion SO ACTA PHYSIOLOGIAE PLANTARUM DT Article AB The native alpine plant Saussurea superba is widely distributed in Qinghai-Tibetan Plateau regions. The leaves of S. superba grow in whorled rosettes, and are horizontally oriented to maximize sunlight exposure. Experiments were conducted in an alpine Kobresia humilis meadow near Haibei Alpine Meadow Ecosystem Research Station (37 degrees 29'-37 degrees 45'N, 101 degrees 12'-101 degrees 33'E; alt. 3200 m). Leaf growth, photosynthetic pigments and chlorophyll fluorescence parameters were measured in expanding leaves of S. superba. The results indicate that leaf area increased progressively from inner younger leaves to outside fully expanded ones, and then slightly decreased in nearly senescent leaves, due to early unfavorable environmental conditions, deviating from the ordinary growth pattern. The specific leaf area decreased before leaves were fully expanded, and the leaf thickness was largest in mature leaves. There were no significant changes in the content of chlorophylls (Chl) and carotenoids (Car), but the ratios of Chl a/b and Car/Chl declined after full expansion of the leaves. The variation of Chl a/b coincided well with changes in photochemical quenching (q(P)) and the fraction of open PSII reaction centers (q(L)). The maximum quantum efficiency of PSII photochemistry after 5 min dark relaxation (F-(v)/F-(m)) continuously increased from younger leaves to fully mature leaves, suggesting that mature leaves could recover more quickly from photoinhibition than younger leaves. The light-harvesting capacity was relatively steady during leaf expansion, as indicated by the maximum quantum efficiency of open PSII centers (F-v(')/F-m(')). UV-absorbing compounds could effectively screen harmful solar radiation, and are a main protection way on the photosynthetic apparatus. The decline of q(P) and q(L) during maturation, together with limitation of quantum efficiency of PSII reaction centers (L-(PFD)), shows a decrease of oxidation state of Q(A) in PSII reaction centers under natural sunlight. Furthermore, light-induced (UNPQ) and non-light-induced quenching (Phi(NO)) were consistent with variation of L-(PFD). It is concluded that the leaves of S. superba could be classified into four functional groups: young, fully expanded, mature, and senescent. Quick recovery from photoinhibition was correlated with protection by screening pigments, and high level of light energy trapping was correlated with preservation of photosynthetic pigments. Increasing of Phi(NPQ) and Phi(NO) during leaves maturation indicates that both thermal dissipation of excessive excitation energy in safety and potential threat to photosynthetic apparatus were strengthened due to the declination of q(P) and q(L), and enhancement of L-(PFD). C1 [Shi, Sheng-Bo; Li, Miao] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810001, Qinghai, Peoples R China. [Shi, Rui] Sun Yat Sen Univ, Sch Life Sci, Guangzhou 510275, Guangdong, Peoples R China. RP Shi, SB (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, 23 Xinning Rd, Xining 810001, Qinghai, Peoples R China. EM sbshi@nwipb.cas.cn TC 1 Z9 3 PD NOV PY 2015 VL 37 IS 11 AR 235 DI 10.1007/s11738-015-1987-4 UT WOS:000365020200016 DA 2023-03-23 ER PT J AU Zhang, T Wang, GX Yang, Y Mao, TX Chen, XP AF Zhang, Tao Wang, Genxu Yang, Yan Mao, Tianxu Chen, Xiaopeng TI Non-growing season soil CO2 flux and its contribution to annual soil CO2 emissions in two typical grasslands in the permafrost region of the Qinghai-Tibet Plateau SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB Non-growing season soil CO2 emissions are very important part of the annual C balance in the Arctic tundra ecosystems, but very limited information is available for the permafrost region of the Qinghai-Tibet Plateau, which hold great quantities of C. We conducted a full year measurement of soil CO2 flux in an alpine meadow and swamp meadow to quantify seasonal dynamics of non-growing season (include winter and initial thaw and freeze period (TFP)) soil CO2 flux and its contribution to annual soil CO2 emissions. Mean soil CO2 flux was higher in TFP (0.38-0.54 mu mol m(-2) s(-1)) than in winter (0.11-0.23 mu mol m(-2) s(-1)), with significant higher in swamp meadow than alpine meadow in the nongrowing season. Soil temperature explained 76-85% of the yearly variation in the soil CO2 flux, with higher temperature sensitivity (Q(10)) in the TFP (5.67-9.43) than in other seasons (2.65-2.99). The cumulative non-growing season soil CO2 emission was 228-358 g CO2 m(-2), accounted for 25-26% of annual emissions. The integrated contribution of non-growing season to annual emission based on season-specific, annual and growing season Q(10) model were 26-27%, 32-34% and 44-45%, respectively, season-specific model may improve the accuracy of estimating the soil CO2 emissions. Our results indicate that non-growing season contributes a large portion of the annual soil CO2 emission in the permafrost region of the Qinghai-Tibet Plateau. Hence, estimating of annual C balance must consider the non-growing season soil CO2 emission, and should not neglect the soil CO2 emission of swamp meadow. (C) 2015 Elsevier Masson SAS. All rights reserved. C1 [Zhang, Tao; Wang, Genxu; Yang, Yan; Mao, Tianxu; Chen, Xiaopeng] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu, Peoples R China. [Zhang, Tao; Mao, Tianxu; Chen, Xiaopeng] Univ Chinese Acad Sci, Beijing 100000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, 9,Block 4,Renminnanlu Rd, Chengdu, Peoples R China. EM wanggx@imde.ac.cn TC 30 Z9 35 PD NOV-DEC PY 2015 VL 71 BP 45 EP 52 DI 10.1016/j.ejsobi.2015.10.004 UT WOS:000366539200006 DA 2023-03-23 ER PT J AU Qi, J Nie, ZN Jiao, T Zhang, DG AF Qi, Juan Nie, Zhongnan Jiao, Ting Zhang, Degang TI Phosphorus and Defoliation Interact and Improve the Growth and Composition of the Plant Community and Soil Properties in an Alpine Pasture of Qinghai-Tibet Plateau SO PLOS ONE DT Article AB Pasture degradation caused by overgrazing and inappropriate fertiliser management is a major production and environmental threat in Qinghai-Tibet Plateau. Previous research has focused on the effects of mixed nitrogen (N) and phosphorus (P) fertiliser and reduced grazing pressure on the plant community of the grassland; however, the role of P and how it interacts with various defoliation (the process of the complete or partial removal of the above-ground parts of plants by grazing or cutting) intensities on the plant and soil of the grassland ecosystem have not been quantified. A field experiment was conducted to quantify how P application in combination of defoliation pressure could impact the dynamic change of the plant and soil in a native alpine grassland ecosystem of the Qinghai-Tibet Plateau, China, from May 2012 to September 2014. A split-plot design with 4 replicates and repeated measures was used to determine the growth and composition of plant community and soil physical and chemical properties under various levels of P fertiliser and defoliation intensity. The results showed that applying 20 kg P/ha increased the herbage yield of Melissitus ruthenica by 68% and total pasture yield by 25%. Close defoliation favoured the growth and plant frequency of the shorter species, whereas lax defoliation favoured that of the taller plant species. Medium P rate and cutting to 3 cm above ground gave an overall best outcome in pasture yield, quality and frequency and soil moisture and nutrient concentration. Application of P fertiliser with a moderate defoliation pressure to promote legume growth and N fixation has the potential to achieve multiple benefits in increasing pasture and livestock production and improving environmental sustainability in the alpine pasture of Qinghai-Tibet Plateau, a fragile and P-deficient ecosystem zone in China and its western neighbouring countries. C1 [Qi, Juan; Nie, Zhongnan; Jiao, Ting; Zhang, Degang] Gansu Agr Univ, Coll Grassland Sci, Lanzhou, Gansu, Peoples R China. [Nie, Zhongnan] Dept Econ Dev Jobs Transport & Resources, Hamilton, Vic, Australia. RP Nie, ZN (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Lanzhou, Gansu, Peoples R China. EM zhongnannie@gmail.com TC 5 Z9 7 PD OCT 29 PY 2015 VL 10 IS 10 AR e0141701 DI 10.1371/journal.pone.0141701 UT WOS:000363920300072 DA 2023-03-23 ER PT J AU Cai, HY Yang, XH Xu, XL AF Cai, Hongyan Yang, Xiaohuan Xu, Xinliang TI Human-induced grassland degradation/restoration in the central Tibetan Plateau: The effects of ecological protection and restoration projects SO ECOLOGICAL ENGINEERING DT Article AB Ecological projects are an important and vital method to help ecosystem adaptation and restoration in response to the environment change and human interference. The accurate and objective assessment of ecological projects will assist ecosystem management and adaption. This study took the central Tibetan Plateau as the study area, where a series of ecological projects has been implemented since 2005 to prevent grassland degradation by protecting and restoring the grasslands. Our aim is to explore where and to what extent the ecological projects influenced the grassland variation, using SPOT NDVI-based residual trend as an indicator. The results indicated that before the projects (between 1998 and 2004), human-induced degradation characterized the grassland. However, a general grassland restoration was detected after the projects from 2005 to 2012. Moreover, over 60% of project plots had positive trends in the NDVI residuals. From the spatial patterns, project-induced restoration was detected in the western and northern regions, such as Maduo, Dongde and Xinghai counties. For the eastern regions, the human-induced degradation has been generally mitigated and yet not reversed after the projects. Our results indicated that ecological protection and restoration projects in the central Tibetan Plateau have mitigated the grassland degradation and even reversed the degradation in some areas, and also suggested that the NDVI-based residual trend is a useful indicator for assessing the effectiveness of the ecological projects in alpine regions. (C) 2015 Elsevier B.V. All rights reserved. C1 [Cai, Hongyan; Yang, Xiaohuan; Xu, Xinliang] Chinese Acad Sci, State Key Lab Resources & Environm Informat Syst, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. RP Xu, XL (通讯作者)，Chinese Acad Sci, State Key Lab Resources & Environm Informat Syst, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. EM caihy@igsnrr.ac.cn; yangxh@igsnrr.ac.cn; xuxl@lreis.ac.cn TC 138 Z9 170 PD OCT PY 2015 VL 83 BP 112 EP 119 DI 10.1016/j.ecoleng.2015.06.031 UT WOS:000360812000016 DA 2023-03-23 ER PT J AU Chen, YC Sun, J Xie, FT Wang, XD Cheng, GW Lu, XY AF Chen, Youchao Sun, Jian Xie, Fangting Wang, Xiaodan Cheng, Genwei Lu, Xuyang TI Litter chemical structure is more important than species richness in affecting soil carbon and nitrogen dynamics including gas emissions from an alpine soil SO BIOLOGY AND FERTILITY OF SOILS DT Article AB Plant litter can influence many fundamental ecosystem functions during decomposition. However, the mechanism of litter diversity effects on belowground ecological processes remains unclear, especially with regard to soil C and the N cycle in alpine ecosystems. In this study, we incubated the litter of four alpine steppe species (SP: Stipa purpurea, CM: Carex moorcroftii, LP: Leontopodium pusillum, AN: Artemisia nanschanica) alone or in mixture with soil. The litter-mixing experiment was conducted to determine the effects of litter diversity on soil C and N dynamics in an alpine steppe in Northern Tibet. Litter treatments significantly enhanced CO2 and N2O emissions and decreased CH4 immobilization in general; soil organic C, total N, water soluble organic C, water soluble organic N, microbial biomass C, microbial biomass N, and urease activity were also enhanced, while soil total inorganic N was decreased by litter treatments. Plant species richness poorly affected soil C and N dynamics, while litter chemical structure, such as C, N, lingin:N, phenol:N, cellulose, and cellulose:N, significantly affected soil C and N dynamics. Non-additive effects of litter mixture were predominant on soil C and N dynamics, while antagonistic effects were more frequent than synergistic effects. These results indicated that litter addition can significantly impact soil C and N dynamics through non-additive effects of litter mixture, and litter chemical structure is more important than species richness in affecting soil C and N dynamics of the alpine steppe in Northern Tibet. C1 [Chen, Youchao; Xie, Fangting; Wang, Xiaodan; Cheng, Genwei; Lu, Xuyang] Chinese Acad Sci, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Chen, Youchao; Xie, Fangting] Chinese Acad Sci, Grad Univ Chinese Acad Sci, Beijing 100101, Peoples R China. [Sun, Jian] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. RP Lu, XY (通讯作者)，Chinese Acad Sci, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. EM xylu@imde.ac.cn TC 27 Z9 30 PD OCT PY 2015 VL 51 IS 7 BP 791 EP 800 DI 10.1007/s00374-015-1025-0 UT WOS:000361348100003 DA 2023-03-23 ER PT J AU Fassnacht, FE Li, L Fritz, A AF Fassnacht, Fabian Ewald Li, Li Fritz, Andreas TI Mapping degraded grassland on the Eastern Tibetan Plateau with multi-temporal Landsat 8 data - where do the severely degraded areas occur? SO INTERNATIONAL JOURNAL OF APPLIED EARTH OBSERVATION AND GEOINFORMATION DT Article AB The Tibetan Plateau in Western China is the world's largest alpine landscape, sheltering a rich diversity of native flora and fauna. In the past few decades, the Tibetan Plateau was found to suffer from grassland degradation processes. Grassland degradation is assumed to not only endanger biodiversity but also to increase the risk for natural hazards in other parts of the country which are ecologically and hydrologically connected to the area. However, the mechanisms behind the degradation processes remain poorly understood due to scarce baseline data and insufficient scientific research. We argue that remote sensing data can help to better understand degradation processes and patterns by: (1) identifying the distribution of severely degraded areas and (2) comparing the patterns of key spatial attributes of the identified areas (altitude above sea level, aspect, slope, administrative districts) with existing theories on degradation drivers. Therefore, we applied four Landsat 8 images covering large portions of the three counties Jigzhi, Baima and Darlag in the Eastern Tibetan Plateau. The dates of the Landsat scenes were selected to cover differing phenological stages of the ecosystem. Reference data were collected with a remotely piloted aircraft and a standard consumer RGB camera. To exploit the phenological information in the Landsat data as well as deal with the problem of cloud cover in multiple images, we developed a straightforward PCA-based procedure to merge the Landsat scenes. The merged Landsat data served as input to a supervised support vector machine classification which was validated with an iterative bootstrap procedure and an additional independent validation set. The considered classes were "high-cover grassland", "grassland (including several stages of grassland vitality)", "(severely) degraded grassland", "green shrubland", "grey shrubland", "urban areas" and "water bodies". Kappa accuracies ranged between 0.84 and 0.93 in the iterative procedure, while the independent validation led to a kappa accuracy of 0.76. Mean producer's and user's accuracies for all classes were higher than 80%, and confusion mainly occurred between the two shrubland classes and between the three grassland classes. Analysis of the slope, aspect and altitude values of the vegetation classes revealed that the degraded areas mostly occurred at the higher altitudes of the study area (4300-4600 m), with no strong connection to any specific slope or aspect. High-cover grassland was mostly located on sunny slopes at lower altitudes (less than 4300 m), while shrubland preferred shady, relatively steep slopes across all altitudes. These observations proved to be stable across the examined counties, while the proportions of land-cover classes differed between the examined regions. Most counties showed 5-7% severely degraded land cover. Darlag, the county located at the edge of the permafrost zone, and featuring the highest average altitude and lowest annual temperature and precipitation, was found to suffer from larger areas of severe degradation (14%). Therefore, our findings support a strong connection between degradation patterns and climatic as well as altitudinal gradients, with an increased degradation risk for high altitude areas and areas in colder and drier climatic zones. This is relevant information for pastoral management to avoid further degradation of high altitude pastures. (C) 2015 Elsevier B.V. All rights reserved. C1 [Fassnacht, Fabian Ewald] Karlsruhe Inst Technol, Inst Geog & Geoecol, D-76131 Karlsruhe, Germany. [Li, Li] Univ Freiburg, Wildlife Ecol & Management, D-79102 Freiburg, Germany. [Fritz, Andreas] Univ Freiburg, Remote Sensing & Landscape Informat Syst, D-79102 Freiburg, Germany. RP Fassnacht, FE (通讯作者)，Karlsruhe Inst Technol, Inst Geog & Geoecol, Kaiserstr 12, D-76131 Karlsruhe, Germany. EM fabian.fassnacht@kit.edu; li.li@wildlife.uni-freiburg.de; andreas.fritz@felis.uni-freiburg.de TC 51 Z9 55 PD OCT PY 2015 VL 42 BP 115 EP 127 DI 10.1016/j.jag.2015.06.005 UT WOS:000362061200012 DA 2023-03-23 ER PT J AU Xu, B Li, JY Jin, YX Wang, ZL Qin, ZH Wu, MQ Wang, DL Zhang, J Ma, HL Yang, XC AF Xu, B. Li, J. Y. Jin, Y. X. Wang, Z. L. Qin, Z. H. Wu, M. Q. Wang, D. L. Zhang, J. Ma, H. L. Yang, X. C. TI Temporal and spatial variations of grassland desertification monitoring in Tibet of China SO INTERNATIONAL JOURNAL OF REMOTE SENSING DT Article; Proceedings Paper CT 4th International Symposium on Recent Advances in Quantitative Remote Sensing (RAQRS) CY SEP 22-26, 2014 CL Global Change Unit Univ Valencia, Torrent, SPAIN HO Global Change Unit Univ Valencia AB Tibet, the largest region of the Qinghai-Tibet Plateau, is undergoing extensive grassland deterioration and desertification due to both human and natural factors. Alpine meadow and grassland restoration is difficult after degradation; consequently, the desertification of the Tibetan grassland has attracted substantial social attention. This article considered Amdo, Baingoin, Coqen, and Zhongba counties in Tibet as the study areas, employed remote-sensing data, and developed Tibetan grassland desertification classification indices based on field surveys. Moreover, this study used spectral mixture analysis (SMA) methods to interpret remote-sensing image data from the study areas during three periods (1990, 2000, and 2009) and considered the bare sand (gravel) area proportion as the main basis for the evaluation of grassland desertification. The results of this study demonstrate that the slightly, moderately, and severely desertified grasslands of the monitoring zone covered a total area of 114,113.16km(2) in 1990, accounting for 82.12% of the study area. The area exhibited no change in 2000 and decreased by 4472.31km(2) in 2009. The severely desertified grassland area declined from 1990 to 2009. The degree of grassland desertification in these four Tibetan counties diminished from 1990 to 2009, and the grassland desertification area exhibited a gradual reduction during the same period. Regarding other soil coverage types, the ice and snow area markedly changed and declined to approximately one-third of its original extent during these 20years, and most of the ice and snow area was converted to bare land and various types of desertified grassland. C1 [Xu, B.; Li, J. Y.; Jin, Y. X.; Qin, Z. H.; Wang, D. L.; Ma, H. L.; Yang, X. C.] Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Key Lab Agri Informat, Minist Agr, Beijing 100081, Peoples R China. [Li, J. Y.] Ludong Univ, Coll Geog & Planning, Yantai 264025, Peoples R China. [Wang, Z. L.; Wu, M. Q.] Chinese Acad Sci, Ecoenvironm Sci Res Ctr, State Key Lab Urban & Reg Ecol, Beijing 100085, Peoples R China. [Zhang, J.] Planning & Design Inst Forest Prod Ind, State Forestry Adm, Beijing 100714, Peoples R China. RP Yang, XC (通讯作者)，Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Key Lab Agri Informat, Minist Agr, Beijing 100081, Peoples R China. EM yangxiuchun@caas.cn TC 7 Z9 8 PD OCT PY 2015 VL 36 IS 19-20 SI SI BP 5150 EP 5164 DI 10.1080/01431161.2015.1066526 UT WOS:000364334500024 DA 2023-03-23 ER PT J AU Su, JH Aryal, A Nan, ZB Ji, WH AF Su, Junhu Aryal, Achyut Nan, Zhibiao Ji, Weihong TI Climate Change-Induced Range Expansion of a Subterranean Rodent: Implications for Rangeland Management in Qinghai-Tibetan Plateau SO PLOS ONE DT Article AB Disturbances, both human-induced and natural, may re-shape ecosystems by influencing their composition, structure, and functional processes. Plateau zokor (Eospalax baileyi) is a typical subterranean rodent endemic to Qinghai-Tibetan Plateau (QTP), which are considered ecosystem engineers influencing the alpine ecosystem function. It is also regarded as a pest aggravating the degradation of overgrazed grassland and subject to regular control in QTP since 1950s. Climate change has been predicted in this region but little research exists exploring its impact on such subterranean rodent populations. Using plateau zokor as a model, through maximum entropy niche-based modeling (Maxent) and sustainable habitat models, we investigate zokor habitat dynamics driven by the future climate scenarios. Our models project that zokor suitable habitat will increase by 6.25% in 2050 in QTP. The predication indicated more threats in terms of grassland degradation as zokor suitable habitat will increase in 2050. Distribution of zokors will shift much more in their southern range with lower elevation compare to northern range with higher elevation. The estimated distance of shift ranges from 1 km to 94 km from current distribution. Grassland management should take into account such predictions in order to design mitigation measures to prevent further grassland degradation in QTP under climate change scenarios. C1 [Su, Junhu; Ji, Weihong] Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ,Pratacultural Engn Lab Gansu Prov,Sin, Lanzhou 730070, Peoples R China. [Su, Junhu; Aryal, Achyut; Ji, Weihong] Gansu Agr Univ, Gansu Agr Univ Massey Univ Res Ctr Grassland Biod, Lanzhou 730070, Peoples R China. [Su, Junhu; Nan, Zhibiao] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Aryal, Achyut; Ji, Weihong] Massey Univ, Inst Nat & Math Sci, Auckland, New Zealand. RP Ji, WH (通讯作者)，Gansu Agr Univ, Coll Grassland Sci, Key Lab Grassland Ecosyst, Minist Educ,Pratacultural Engn Lab Gansu Prov,Sin, Lanzhou 730070, Peoples R China. EM j.j.weihong@massey.ac.nz TC 38 Z9 48 PD SEP 25 PY 2015 VL 10 IS 9 AR e0138969 DI 10.1371/journal.pone.0138969 UT WOS:000361800700132 DA 2023-03-23 ER PT J AU Schleuss, PM Heitkamp, F Sun, Y Miehe, G Xu, XL Kuzyakov, Y AF Schleuss, Per-Marten Heitkamp, Felix Sun, Yue Miehe, Georg Xu, Xingliang Kuzyakov, Yakov TI Nitrogen Uptake in an Alpine Kobresia Pasture on the Tibetan Plateau: Localization by N-15 Labeling and Implications for a Vulnerable Ecosystem SO ECOSYSTEMS DT Article AB Grasslands are very important regionally and globally because they store large amounts of carbon (C) and nitrogen (N) and provide food for grazing animals. Intensive degradation of alpine grasslands in recent decades has mainly impacted the upper root-mat/soil horizon, with severe consequences for nutrient uptake in these nutrient-limited ecosystems. We used N-15 labeling to identify the role of individual soil layers for N-uptake by Kobresia pygmaea-the dominating plant in the degraded Tibetan pasture ecosystems. We hypothesized a very efficient N-uptake corresponding mainly to the vertical distribution of living roots (topsoil > subsoil). We assume that K. pygmaea develops a very dense root-mat, which has to be maintained by small aboveground biomass, to enable this efficient N-uptake. Consequently, a higher N-investment into roots compared to shoots was hypothesized. The N-15 recovery in whole plants (similar to 70%) indicated very efficient N-uptake from the upper injection depths (0-5 cm). The highest N-15 amounts were recovered in root biomass, whereby N-15 recovery in roots strongly decreased with depth. In contrast, N-15 recovery in shoots was generally low (similar to 18%) and independent of the N-15 injection depth. This clearly shows that the low N demand of Kobresia shoots can be easily covered by N-uptake from any depth. Less living root biomass in lower versus upper soil was compensated by a higher specific activity of roots for N-uptake. The N-15 allocation into roots was on average 1.7 times higher than that into shoots, which agreed well with the very high R/S ratio. Increasing root biomass is an efficient strategy of K. pygmaea to compete for belowground resources at depths and periods with available resources. This implies high C-costs to maintain root biomass (similar to 6.0 kg DM m(-2)), which must be covered by a very low amount of photosynthetically active shoots (0.3 kg DM m(-2)). It also suggests that Kobresia grasslands react extremely sensitively toward changes in climate and management that disrupt this above-/belowground trade-off mechanism. C1 [Schleuss, Per-Marten; Sun, Yue; Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, D-37077 Gottingen, Germany. [Heitkamp, Felix] Univ Gottingen, Fac Geosci & Geog, Landscape Ecol, D-37077 Gottingen, Germany. [Sun, Yue; Xu, Xingliang] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Miehe, Georg] Univ Marburg, Fac Geog, D-35032 Marburg, Germany. [Kuzyakov, Yakov] Univ Gottingen, Dept Agr Soil Sci, D-37077 Gottingen, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan, Russia. RP Schleuss, PM (通讯作者)，Univ Gottingen, Dept Soil Sci Temperate Ecosyst, Busgenweg 2, D-37077 Gottingen, Germany. EM pschleu1@gwdg.de TC 40 Z9 47 PD SEP PY 2015 VL 18 IS 6 BP 946 EP 957 DI 10.1007/s10021-015-9874-9 UT WOS:000360543100002 DA 2023-03-23 ER PT J AU Xue, X Peng, F You, QG Xu, MH Dong, SY AF Xue, Xian Peng, Fei You, Quangang Xu, Manhou Dong, Siyang TI Belowground carbon responses to experimental warming regulated by soil moisture change in an alpine ecosystem of the Qinghai-Tibet Plateau SO ECOLOGY AND EVOLUTION DT Article AB Recent studies found that the largest uncertainties in the response of the terrestrial carbon cycle to climate change might come from changes in soil moisture under the elevation of temperature. Warming-induced change in soil moisture and its level of influence on terrestrial ecosystems are mostly determined by climate, soil, and vegetation type and their sensitivity to temperature and moisture. Here, we present the results from a warming experiment of an alpine ecosystem conducted in the permafrost region of the Qinghai-Tibet Plateau using infrared heaters. Our results show that 3years of warming treatments significantly elevated soil temperature at 0-100cm depth, decreased soil moisture at 10cm depth, and increased soil moisture at 40-100cm depth. In contrast to the findings of previous research, experimental warming did not significantly affect NH4+-N, NO3--N, and heterotrophic respiration, but stimulated the growth of plants and significantly increased root biomass at 30-50cm depth. This led to increased soil organic carbon, total nitrogen, and liable carbon at 30-50cm depth, and increased autotrophic respiration of plants. Analysis shows that experimental warming influenced deeper root production via redistributed soil moisture, which favors the accumulation of belowground carbon, but did not significantly affected the decomposition of soil organic carbon. Our findings suggest that future climate change studies need to take greater consideration of changes in the hydrological cycle and the local ecosystem characteristics. The results of our study will aid in understanding the response of terrestrial ecosystems to climate change and provide the regional case for global ecosystem models. C1 [Xue, Xian; Peng, Fei; You, Quangang; Xu, Manhou; Dong, Siyang] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. RP Xue, X (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Key Lab Desert & Desertificat, 320 West Donggang Rd, Lanzhou 730000, Peoples R China. EM xianxue@lzb.ac.cn TC 19 Z9 21 PD SEP PY 2015 VL 5 IS 18 BP 4063 EP 4078 DI 10.1002/ece3.1685 UT WOS:000362090700018 DA 2023-03-23 ER PT J AU Zhu, P Chen, RS Song, YX Liu, GX Chen, T Zhang, W AF Zhu, Ping Chen, Rensheng Song, Yaoxuan Liu, Guangxiu Chen, Tuo Zhang, Wei TI Effects of land cover conversion on soil properties and soil microbial activity in an alpine meadow on the Tibetan Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB Land cover conversion intensively occurred in the Tibetan Plateau of China during the past decades. However, responses of soil properties and soil microbial activities to land cover conversion under different land cover types have not been fully understood. The objective was to assess the effects of land cover conversion on soil C and N stocks and soil microbial properties of topsoil of an alpine meadow in the Tibetan Plateau. Soil cores of surface soil (0-20 cm) were collected from three adjacent land cover types: native alpine meadow, artificial grassland and mound-shaped denuded land. Soil microbial metabolic diversity was measured using Biolog EcoPlates. Significant losses of SOC and TN storages were subject to land cover conversion in topsoil, decreasing 14.5 and 10.9 % of alpine meadow to artificial grassland and 52.9 and 51.7 % to denuded land. Alpine meadow soils had the highest soil microbial biomass and microbial metabolic activity of three land cover types. Microbial biomass and microbial metabolic activity decreased markedly after alpine meadow conversion to denuded land. Land use conversion from original alpine meadow to artificial grassland and denuded land caused decline in soil organic carbon density, total nitrogen density and soil microbial activity. Soil carbon emissions from alpine meadow conversion were released to the atmosphere and could influence climatic change. C1 [Zhu, Ping; Chen, Rensheng; Song, Yaoxuan] Chinese Acad Sci, Qilian Alpine Ecol & Hydrol Res Stn, Lanzhou 730000, Peoples R China. [Zhu, Ping; Chen, Rensheng; Song, Yaoxuan; Liu, Guangxiu; Chen, Tuo; Zhang, Wei] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Chen, RS (通讯作者)，Chinese Acad Sci, Qilian Alpine Ecol & Hydrol Res Stn, Lanzhou 730000, Peoples R China. EM crs2008@lzb.ac.cn TC 8 Z9 11 PD SEP PY 2015 VL 74 IS 5 BP 4523 EP 4533 DI 10.1007/s12665-015-4509-1 UT WOS:000360401400070 DA 2023-03-23 ER PT J AU Liu, B You, GY Li, R Shen, WS Yue, YM Lin, NF AF Liu, Bo You, Guangyong Li, Ru Shen, Weishou Yue, Yuemin Lin, Naifeng TI Spectral characteristics of alpine grassland and their changes responding to grassland degradation on the Tibetan Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB Remote sensing is used as the indispensable technology in alpine grassland degradation assessment especially at regional scale on the Tibetan Plateau. However, the lack of field spectral data, as the foundation of remote sensing, due to the formidable natural and climate conditions hinders the understanding of spectral characteristics of alpine grassland and their degradation assessment. In this study, spectral characteristics of alpine grasslands and their changes responding to degradation were explored. The results showed that the main spectral characteristics for discriminating the dominant species of alpine meadow (Kobresia littledalei and Kobresia pygmaea), alpine steppe (Stipa purpurea) and desert (Potentilla fruticosa) are spectral features of chlorophyll, cellulose and water which are related to their growth form, plant inclination and residue of withered leaf sheaths. The spectral curves of alpine meadow have a much smaller variety over the whole spectral region compared to those of alpine steppe and desert which generally have weaker chlorophyll and water absorption features and more noticeable non-vegetation features. Different grassland degradation processes exhibit different patterns of spectral characteristics change due to the species composition, vegetation succession, vegetation coverage and soil background. Grassland degradation can happen without obvious vegetation coverage reduction or even with an increment of NDVI (normalized difference vegetation index). Therefore, the assessment of grassland degradation cannot be fulfilled well using single vegetation index or spectral feature. The combination of several vegetation indices or hyperspectral remote sensing along with the priori knowledge is needed in order to perform the assessment more accurately in further studies. C1 [Liu, Bo] Nanjing Univ Informat Sci & Technol, Sch Geog & Remote Sensing, Nanjing 210044, Jiangsu, Peoples R China. [You, Guangyong; Shen, Weishou; Lin, Naifeng] Nanjing Inst Environm Sci, Minist Environm Protect, Nanjing 210042, Jiangsu, Peoples R China. [Li, Ru] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Beijing 100101, Peoples R China. [Yue, Yuemin] Chinese Acad Sci, Inst Subtrop Agr, Changsha 410125, Hunan, Peoples R China. RP Shen, WS (通讯作者)，Nanjing Inst Environm Sci, Minist Environm Protect, Nanjing 210042, Jiangsu, Peoples R China. EM shenws@163.com TC 21 Z9 23 PD AUG PY 2015 VL 74 IS 3 BP 2115 EP 2123 DI 10.1007/s12665-015-4196-y UT WOS:000358073800023 DA 2023-03-23 ER PT J AU Wu, JS Yang, PW Zhang, XZ Shen, ZX Yu, CQ AF Wu, Jianshuang Yang, Pengwan Zhang, Xianzhou Shen, Zhenxi Yu, Chengqun TI Spatial and climatic patterns of the relative abundance of poisonous vs. non-poisonous plants across the Northern Tibetan Plateau SO ENVIRONMENTAL MONITORING AND ASSESSMENT DT Article AB It is the most serious challenge to promote degraded grassland recovery currently facing the developing Tibetan Autonomous Region. We conducted field surveys of 75 grazing sites between 2009 and 2012 across the Northern Tibetan Plateau and described the spatial and climatic patterns of the occurrence of poisonous plants. Our results showed lower ratios of species richness (SprRatio), coverage (CovRatio), and biomass (BioRatio) of non-poisonous vs. poisonous plants in the semi-arid alpine steppe zone, where the growing season precipitation (GSP) is between 250 and 350 mm; however, this result is in contrast to the relatively wetter meadow (GSP >350 mm) and much drier desert-steppe (GSP <250mm) communities. Results from generalized additive models (GAMs) further confirmed that precipitation is primarily responsible for the initially decreasing and then increasing tendency of compositional ratios of non-poisonous to poisonous species. The wide confidence bands at GSP <250 mm indicated that precipitation is not an effective indicator for predicting compositional changes in desert-steppe communities. When mean annual livestock grazing pressure was incorporated into the optimal GAMs, the model performance improved: the Akaike information criterion (AIC) decreased by 1.20 for SprRatio and 3.09 for BioRatio, and the deviance explained (R2) increased by 6.0 % for SprRatio and 3.6 % for BioRatio. Therefore, more detailed information on grazing disturbance (timing, frequency, and density) should be collected to disentangle the relative contribution of climate change and grazing activities to changes in community assembly and ecological functions of alpine grasslands on the Northern Tibetan Plateau. C1 [Wu, Jianshuang; Yang, Pengwan; Zhang, Xianzhou; Shen, Zhenxi; Yu, Chengqun] Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Wu, Jianshuang] Free Univ Berlin, Funct Biodivers, Dahlem Ctr Plant Sci, D-14195 Berlin, Germany. [Yang, Pengwan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Wu, JS (通讯作者)，Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modelling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM wujs.07s@igsnrr.ac.cn TC 11 Z9 15 PD AUG PY 2015 VL 187 IS 8 AR 491 DI 10.1007/s10661-015-4707-z UT WOS:000358782300010 DA 2023-03-23 ER PT J AU Harris, RB Wang, WY Badinqiuying Smith, AT Bedunah, DJ AF Harris, Richard B. Wang Wenying Badinqiuying Smith, Andrew T. Bedunah, Donald J. TI Herbivory and Competition of Tibetan Steppe Vegetation in Winter Pasture: Effects of Livestock Exclosure and Plateau Pika Reduction SO PLOS ONE DT Article AB Rangeland degradation has been identified as a serious concern in alpine regions of western China on the Qinghai-Tibetan plateau (QTP). Numerous government-sponsored programs have been initiated, including many that feature long-term grazing prohibitions and some that call for eliminating pastoralism altogether. As well, government programs have long favored eliminating plateau pikas (Ochotona curzoniae), assumed to contribute to degraded conditions. However, vegetation on the QTP evolved in the presence of herbivory, suggesting that deleterious effects from grazing are, to some extent, compensated for by reduced plant-plant competition. We examined the dynamics of common steppe ecosystem species as well as physical indicators of rangeland stress by excluding livestock and reducing pika abundance on experimental plots, and following responses for 4 years. We established 12 fenced livestock exclosures within pastures grazed during winter by local pastoralists, and removed pikas on half of these. We established paired, permanent vegetation plots within and outside exclosures and measured indices of erosion and biomass of common plant species. We observed modest restoration of physical site conditions (reduced bare soil, erosion, greater vegetation cover) with both livestock exclusion and pika reduction. As expected in areas protected from grazing, we observed a reduction in annual productivity of plant species avoided by livestock and assumed to compete poorly when protected from grazing. Contrary to expectation, we observed similar reductions in annual productivity among palatable, perennial graminoids under livestock exclusion. The dominant grass, Stipa purpurea, displayed evidence of density-dependent growth, suggesting that intra-specific competition exerted a regulatory effect on annual production in the absence of grazing. Complete grazing bans on winter pastures in steppe habitats on the QTP may assist in the recovery of highly eroded pastures, but may not increase annual vegetative production. C1 [Harris, Richard B.] Univ Montana, Dept Ecosyst & Conservat Sci, Missoula, MT 59812 USA. [Wang Wenying] Qinghai Normal Univ, Xining, Qinghai, Peoples R China. [Badinqiuying; Smith, Andrew T.] Arizona State Univ, Dept Life Sci, Tempe, AZ USA. [Bedunah, Donald J.] Univ Montana, Dept Forest Management, Missoula, MT 59812 USA. RP Harris, RB (通讯作者)，Washington Dept Fish & Wildlife, Olympia, WA 98501 USA. EM rharris@montana.com TC 39 Z9 43 PD JUL 24 PY 2015 VL 10 IS 7 AR e0132897 DI 10.1371/journal.pone.0132897 UT WOS:000358622000043 DA 2023-03-23 ER PT J AU Zhang, H Wang, ZF Zhang, YL Ding, MJ Li, LH AF Zhang, Hua Wang, Zhaofeng Zhang, Yili Ding, Mingjun Li, Lanhui TI Identification of traffic-related metals and the effects of different environments on their enrichment in roadside soils along the Qinghai-Tibet highway SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The road transportation could affect roadside soils environment detrimentally, including heavy metal enrichment. In order to identify and evaluate the enrichment of heavy metals resulted from road transportation on the Tibetan Plateau, the 11 heavy metals (V, Cr, Co, Ni, Cu, Zn, As, Cd, Rb, Pb and Tl) in the topsoil (0-10 cm depth) from four sites along the Qinghai-Tibet highway were discussed in this study. Our results indicate that heavy metals such as Cr, Cu, Zn, As, Cd and Pb are related to road transportation. The content of most of these heavy metals in roadside soils decreased exponentially with the distance from the road, as did some of the Nemero Synthesis Indexes (PN values). The contamination factor for the traffic-related metals ranged from 0.56 (no pollution) to 5.67 (considerable pollution) and the Nemero Synthesis Indexes of these heavy metals ranged from 0.80 (no pollution) to 4.49 (severe pollution). Cd was of priority concern as it had the highest contamination factor. The highest PN value for these traffic-related heavy metals was found in soils at site TTH (alpine steppe). Although transportation contributed to the high contents of these traffic-related metals in roadside environments, regional differences such as wind and the terrain also had significant relationship with their enrichment in these roadside soils. The roadside distance at which there is a potential risk to livestock and wildlife from the contamination of soils by heavy metals should be determined scientifically along the Qinghai-Tibet highway, based on the different natural environments found in the region. (C) 2015 Elsevier B.V. All rights reserved. C1 [Zhang, Hua; Wang, Zhaofeng; Zhang, Yili] Chinese Acad Sci, Key Lab Land Surface Pattern & Simulat, IGSNRR, Beijing 100101, Peoples R China. [Zhang, Hua; Ding, Mingjun; Li, Lanhui] Jiangxi Normal Univ, Minist Educ, Key Lab Poyang Lake Wetland & Watershed Res, Nanchang 330022, Peoples R China. [Zhang, Yili] Chinese Acad Sci, Ctr Excellence & Innovat Tibetan Plateau Earth Sy, Beijing 100101, Peoples R China. RP Zhang, YL (通讯作者)，Chinese Acad Sci, Key Lab Land Surface Pattern & Simulat, IGSNRR, 11 A Datun Rd, Beijing 100101, Peoples R China. EM zhangyl@igsnrr.ac.cn TC 101 Z9 111 PD JUL 15 PY 2015 VL 521 BP 160 EP 172 DI 10.1016/j.scitotenv.2015.03.054 UT WOS:000353909000019 DA 2023-03-23 ER PT J AU Gou, XL Tan, B Wu, FZ Yang, WQ Xu, ZF Li, ZP Zhang, XT AF Gou, Xiaolin Tan, Bo Wu, Fuzhong Yang, Wanqin Xu, Zhengfeng Li, Zhiping Zhang, Xitao TI Seasonal Dynamics of Soil Microbial Biomass C and N along an Elevational Gradient on the Eastern Tibetan Plateau, China SO PLOS ONE DT Article AB Little information is available on the seasonal response of soil microbial biomass to climate warming even though it is very sensitive to climate change. A two-year field experiment was conducted in the subalpine and alpine forests of the eastern Tibetan Plateau, China. The intact soil cores from 3,600 m site were incubated in three elevations (3,000 m, 3,300 m and 3,600 m) to simulate climate warming. Soil microbial biomass carbon (MBC) and nitrogen (MBN) were measured at different periods (early growing season [EG], late growing season [LG], onset of soil freezing period [OF], deep soil frozen period [DF] and soil thawing period [ET]) from May 2010 to August 2012. Average air temperature and soil temperature increased with the decrease of elevation during the experimental period. MBC and MBN showed a sharp decrease during the OF and ET in both organic layer and mineral layer at the three sites. Additionally, a relatively high MBC was observed during the DF. MBC and MBN in the soil organic layer decreased with the decrease of elevation but the opposite was true in the mineral soil layer. Warming had stronger effects on soil microbial biomass in the organic layer than in the mineral soil layer. The results indicated that future warming would alter soil microbial biomass and biogeochemical cycling in the forest ecosystems on the eastern Tibetan Plateau. C1 [Gou, Xiaolin; Tan, Bo; Wu, Fuzhong; Yang, Wanqin; Xu, Zhengfeng; Li, Zhiping; Zhang, Xitao] Sichuan Agr Univ, Key Lab Ecol Forestry Engn, Inst Ecol & Forestry, Chengdu 611130, Peoples R China. RP Yang, WQ (通讯作者)，Sichuan Agr Univ, Key Lab Ecol Forestry Engn, Inst Ecol & Forestry, 211 Huimin Rd, Chengdu 611130, Peoples R China. EM scyangwq@163.com TC 8 Z9 11 PD JUL 6 PY 2015 VL 10 IS 7 AR e0132443 DI 10.1371/journal.pone.0132443 UT WOS:000358157600270 DA 2023-03-23 ER PT J AU Shang, ZH Hou, YC Pan, DF Yang, SH Shi, JJ Ding, LM Long, RJ AF Shang, Zhanhuan Hou, Yaochen Pan, Duofeng Yang, Shihai Shi, Jianjun Ding, Luming Long, Ruijun TI Recruitment of seedlings versus ramets as affected by pasture degradation in alpine meadows and the implications for ecological restoration SO PLANT ECOLOGY & DIVERSITY DT Article AB Background: The degradation of alpine meadows on the Qinghai-Tibetan Plateau (QTP) has an impact on vegetation recruitment from seedlings and ramets.Aims: Understanding the relative contribution of recruitment by seedling and ramet in alpine meadows is for the ecological restoration of degraded grasslands on the QTP.Methods: An experiment was conducted to investigate seedling and ramet densities, species composition and their relationships with standing vegetation in plots representative of non-degraded (ND), lightly (LD), moderately (MD) and severely degraded (SD) alpine meadows.Results: With increasing degradation and the reduction in vegetation cover, the number of seedlings and ramets declined. The proportion of young plants arising from seedlings was low, with the majority of species reproducing clonally. The establishment of seedlings of forbs in SD meadows led to species-rich, forb-dominant vegetation in these areas.Conclusions: LD and MD meadows appear to be able to be managed by reduced grazing for the restoration of grass- and sedge-dominated pastures. In contrast, restoration of SD meadows will require additional intervention, such as of seeding and weed eradication. C1 [Shang, Zhanhuan; Ding, Luming; Long, Ruijun] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. [Hou, Yaochen] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730000, Peoples R China. [Pan, Duofeng] Heilongjiang Acad Agr Sci, Grassland Inst, Haerbin, Peoples R China. [Yang, Shihai] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. [Shi, Jianjun] Qinghai Acad Anim & Vet Sci, Inst Grassland Sci, Xining, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Peoples R China. EM shangzhh@lzu.edu.cn TC 5 Z9 8 PD JUL 4 PY 2015 VL 8 IS 4 BP 547 EP 557 DI 10.1080/17550874.2015.1050710 UT WOS:000361689200001 DA 2023-03-23 ER PT J AU He, SY Richards, K AF He, Siyuan Richards, Keith TI Impact of Meadow Degradation on Soil Water Status and Pasture ManagementA Case Study in Tibet SO LAND DEGRADATION & DEVELOPMENT DT Article; Proceedings Paper CT 2nd Scientific Conference on United-Nations-Convention-Combat-Desertification (UNCCD) CY APR 09-12, 2013 CL Bonn, GERMANY AB Alpine meadow dominated by Kobresia pygmaea forms both an important ecosystem and the main pasture resource on the Qinghai-Tibetan Plateau, and its degradation is detrimental to ecosystem health and the pastoral economy. This paper reports research on the impacts of possible degradation on soil and biological properties related to water status, as water availability is fundamental to grass productivity. It also considers herders' perceptions towards, and adaptation to, the changing environment. The research was carried out in and around Kema village in Nagqu Prefecture, Northern Tibet. The biotic and abiotic properties of the K. pygmaea meadow are significantly different in patches with diverse soil and vegetation combinations, which include normal meadow, crusted meadow, and bare soil. Change of species composition, low species diversity, coarsening of soil, and lack of soil moisture and organic matter are found under bare soil after erosion of the turf layer. Low infiltration rates and reduced dew deposition are found under crusted meadow. Herders have witnessed some aspects of the deterioration of meadow quality and have noticed some climatic variations. However, they do not consistently link changing meadow quality to climate change and rarely have a clear idea of what overgrazing is, as although their mobility has been reduced, they may think that they are still using pastures periodically as in transhumance. Adapting current privatisation policies by considering herders' traditions and needs, and balancing scientific knowledge with local perception and knowledge, will help to guarantee long-term benefits through sustainable use of the fragile alpine meadow resource. Copyright (c) 2014 John Wiley & Sons, Ltd. C1 [He, Siyuan; Richards, Keith] Univ Cambridge, Dept Geog, Cambridge CB2 3EN, England. RP He, SY (通讯作者)，Univ Cambridge, Dept Land Econ, Cambridge Ctr Climate Change Mitigat, 19 Silver St, Cambridge CB3 9EP, England. EM sh615@cam.ac.uk TC 37 Z9 38 PD JUL PY 2015 VL 26 IS 5 SI SI BP 468 EP 479 DI 10.1002/ldr.2358 UT WOS:000357780800008 DA 2023-03-23 ER PT J AU Li, J Zhang, FW Lin, L Li, HQ Du, YG Li, YK Cao, GM AF Li, Jing Zhang, Fawei Lin, Li Li, Hongqin Du, Yangong Li, Yikang Cao, Guangmin TI Response of the plant community and soil water status to alpine Kobresia meadow degradation gradients on the Qinghai-Tibetan Plateau, China SO ECOLOGICAL RESEARCH DT Article AB Degradation of alpine Kobresia meadow in the Qinghai-Tibetan Plateau is a serious problem, but its effect on the plant community and soil water status is not fully understood. We chose four homogeneous sites with < 20, 20-70, 70-90, and > 90 % absolute abundance of palatable grasses, and classified them as degradation gradient categories of poor, fair, good, and excellent, respectively. The lowest aboveground biomass and infiltration rate, and the highest root biomass, thickness of mattic epipedon, topsoil (< 10 cm) organic matter content and volumetric ratio of root/soil all occurred in fair plots. There was little fluctuation in plant community diversity and topsoil bulk density among the degradation gradients. Results of non-metric multidimensional scaling suggested that vegetation dynamics along degradation processes were non-equilibrium in the alpine Kobresia meadow. The effects of degradation on soil water content and retention were the highest in the top layer (> 10 cm). The minimum topsoil water content and maximum topsoil water retention both occurred in fair plots, indicating asynchrony between soil water content and holding capacity along degradation gradients, which likely resulted in a non-equilibrium plant community pattern through physiological desiccation and nutrient deficits. Our findings should be highly informative for threshold-based management of the degraded alpine Kobresia meadow in the future. C1 [Li, Jing; Zhang, Fawei; Lin, Li; Li, Hongqin; Du, Yangong; Li, Yikang; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810001, Qinghai, Peoples R China. [Li, Jing; Zhang, Fawei; Lin, Li; Li, Hongqin; Du, Yangong; Li, Yikang; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Qinghai, Peoples R China. RP Zhang, FW (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, 23 Xinning St, Xining 810001, Qinghai, Peoples R China. EM fwzhang@nwipb.cas.cn TC 31 Z9 39 PD JUL PY 2015 VL 30 IS 4 BP 589 EP 596 DI 10.1007/s11284-015-1258-2 UT WOS:000357679000005 DA 2023-03-23 ER PT J AU Miao, FH Guo, ZG Xue, R Wang, XZ Shen, YY AF Miao, Fuhong Guo, Zhenggang Xue, Ran Wang, Xianzhi Shen, Yuying TI Effects of Grazing and Precipitation on Herbage Biomass, Herbage Nutritive Value, and Yak Performance in an Alpine Meadow on the Qinghai-Tibetan Plateau SO PLOS ONE DT Article AB The Qinghai-Tibetan Plateau is a very large land unit and an important terrestrial ecosystem within the Eurasian continent. Because of the harsh climate associated with the high altitude, alpine meadows on the plateau are susceptible to degradation from overgrazing. For this region, and for other alpine meadow pastures internationally, there is a need to define the sustainable stocking rate, to develop sound policy pertaining to future land use. Here we report biomass and liveweight gain per animal and per ha for pastures grazed by yaks at high, medium, or low stocking rates over 4 growing seasons from 2010 to 2013. Measures of herbage nutritive value are reported. The influence of inter-year variation in precipitation on standing herbage biomass was also evaluated. Higher precipitation increased standing herbage biomass and herbage nutritive value, indicating that vegetation suffered summer water deficit even in this environment. The sustainable stocking rate in this environment was determined to be approximately 1 yak ha(-1) (grown from 80 kg to 120 kg liveweight in 90 d). At this stocking rate, yak weight gain per ha was 88% of that achieved at higher stocking rates typically used by farmers, but with little or no evidence of land degradation. C1 [Miao, Fuhong; Guo, Zhenggang; Xue, Ran; Wang, Xianzhi; Shen, Yuying] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. RP Shen, YY (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. EM yy.shen@lzu.edu.cn TC 46 Z9 61 PD JUN 3 PY 2015 VL 10 IS 6 AR e0127275 DI 10.1371/journal.pone.0127275 UT WOS:000355700700056 DA 2023-03-23 ER PT J AU Cao, H Zhao, XQ Wang, SP Zhao, L Duan, JC Zhang, ZH Ge, SD Zhu, XX AF Cao, Hui Zhao, Xinquan Wang, Shiping Zhao, Liang Duan, Jichuang Zhang, Zhenhua Ge, Shidong Zhu, Xiaoxue TI Grazing intensifies degradation of a Tibetan Plateau alpine meadow through plant-pest interaction SO ECOLOGY AND EVOLUTION DT Article AB Understanding the plant-pest interaction under warming with grazing conditions is critical to predict the response of alpine meadow to future climate change. We investigated the effects of experimental warming and grazing on the interaction between plants and the grassland caterpillar Gynaephora menyuanensis in an alpine meadow on the Tibetan Plateau in 2010 and 2011. Our results showed that grazing significantly increased nitrogen concentration in graminoids and sward openness with a lower sward height, sward coverage, and plant litter mass in the community. Grazing significantly increased G.menyuanensis body size and potential fecundity in 2010. The increases in female body size were about twofold greater than in males. In addition, grazing significantly increased G.menyuanensis density and its negative effects on aboveground biomass and graminoid coverage in 2011. We found that G.menyuanensis body size was significantly positively correlated with nitrogen concentration in graminoids but negatively correlated with plant litter mass. Even though warming did not significantly increased G.menyuanensis performance and the negative effects of G.menyuanensis on alpine meadow, the increases in G.menyuanensis growth rate and its negative effect on aboveground biomass under the warming with grazing treatment were significantly higher than those under the no warming with grazing treatment. The positive effects of grazing on G.menyuanensis performance and its damage were exacerbated by the warming treatment. Our results suggest that the fitness of G.menyuanensis would increase under future warming with grazing conditions, thereby posing a greater risk to alpine meadow and livestock production. C1 [Cao, Hui; Zhao, Xinquan; Zhao, Liang; Duan, Jichuang; Zhang, Zhenhua; Ge, Shidong; Zhu, Xiaoxue] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Cao, Hui; Zhu, Xiaoxue] Grad Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhao, Xinquan] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. [Duan, Jichuang] Binhai Res Inst Tianjin, Tianjin 300457, Peoples R China. RP Zhao, XQ (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. EM zhaoxq@cib.ac.cn TC 22 Z9 24 PD JUN PY 2015 VL 5 IS 12 BP 2478 EP 2486 DI 10.1002/ece3.1537 UT WOS:000356370400016 DA 2023-03-23 ER PT J AU Dong, SK Wang, XX Liu, SL Li, YY Su, XK Wen, L Zhu, L AF Dong, S. K. Wang, X. X. Liu, S. L. Li, Y. Y. Su, X. K. Wen, L. Zhu, L. TI Reproductive responses of alpine plants to grassland degradation and artificial restoration in the Qinghai-Tibetan Plateau SO GRASS AND FORAGE SCIENCE DT Article AB Artificial grassland establishment has been implemented in the alpine region of Qinghai-Tibetan Plateau in China as a mitigation tool against grassland degradation, one of the major environmental problems in this region. We hypothesized that both grassland degradation and artificial restoration may alter the reproductive modes of the alpine vegetation at the levels of individual species as well as plant functional groups. By investigating a long-term field study of grassland degradation and artificial restoration experiments, we found that alpine plants can maintain a highly plastic relationship between sexual and asexual reproduction, that is, the alpine plants in degraded grasslands increased their efforts towards sexual reproduction while those in artificially restored grasslands promoted their efforts in vegetative reproduction with in the year after restoration. The high reproductive plasticity of the alpine plants can be regulated through a number of mechanisms, which include changing proportion of clonal species in the plant composition, altering number ratio of sexual and vegetative propagules, shifting biomass allocation for sexual and vegetative reproduction at both individual species and functional group levels. These conclusions demonstrate how crucial it is to consider manipulation of reproductive modes needed to restore the structure and stability of degraded alpine grasslands. C1 [Dong, S. K.; Wang, X. X.; Liu, S. L.; Li, Y. Y.; Su, X. K.; Wen, L.; Zhu, L.] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Dong, S. K.] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 33 Z9 41 PD JUN PY 2015 VL 70 IS 2 BP 229 EP 238 DI 10.1111/gfs.12114 UT WOS:000352797100003 DA 2023-03-23 ER PT J AU Gao, YH Zeng, XY Xie, QY Ma, XX AF Gao, Yongheng Zeng, Xiaoyang Xie, Qingyan Ma, Xingxing TI Release of Carbon and Nitrogen from Alpine Soils During Thawing Periods in the Eastern Qinghai-Tibet Plateau SO WATER AIR AND SOIL POLLUTION DT Article AB Soil thawing can affect the turnover of soil carbon (C) and nitrogen (N) and their release into the atmosphere. However, little has been known about the release of C and N during the thawing of alpine soils in the Qinghai-Tibet Plateau. This study investigated the effects of soil thawing on the release of CO2, CH4, and N2O from alpine peatland soils and alpine meadow soils through an indoor experiment and determined the changes in the dissolved organic C (DOC), dissolved organic N (DON), NO3--N, NH4+-N, and NO2--N concentrations in the soils after soil thawing. The freeze-thaw treatments were performed by incubating the soil columns at mild (-5 degrees C) and severe (-15 degrees C) for 14 days, and then at 5 degrees C for 18 days. The control columns were incubated at 5 degrees C. During thawing, the cumulative CO2 emissions from the severely frozen alpine peatland soils and alpine meadow soils were 36 and 85 % higher than those from the control soils, and the cumulative N2O emissions were 3.9 and 5.8 times higher than those from the control soils. However, the thawing after mild freezing produced no significant effects. The two freezing temperatures significantly increased the release of CH4 from the alpine peatland soils, but the thawing of the severely frozen soils reduced the CH4 uptake of the alpine meadow soils by 27 %. After the severely frozen alpine peatland soils thawed, the concentrations of DOC, DON, NO3--N, NH4+-N, and NO2--N increased significantly, but NO2--N showed no significant changes for the alpine meadow soils. After thawing with mild freezing, DOC in the alpine peatland soils and NH4+-N, NO2--N, and DOC in the alpine meadow soils showed no significant changes. This study indicates that the potential for release of C and N from alpine soils during thawing periods strongly depends on the freezing temperature and soil types. C1 [Gao, Yongheng; Xie, Qingyan; Ma, Xingxing] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolut & Regulat, Chengdu, Peoples R China. [Zeng, Xiaoyang] Sichuan Coll Architectural Technol, Dept Landscape Architecture, Deyang, Peoples R China. RP Gao, YH (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolut & Regulat, Chengdu, Peoples R China. EM yhgao@imde.ac.cn TC 23 Z9 28 PD JUN PY 2015 VL 226 IS 7 AR 209 DI 10.1007/s11270-015-2479-2 UT WOS:000357690100016 DA 2023-03-23 ER PT J AU Wu, PF Zhang, HZ Wang, Y AF Wu, Pengfei Zhang, Hongzhi Wang, Yong TI The response of soil macroinvertebrates to alpine meadow degradation in the Qinghai-Tibetan Plateau, China SO APPLIED SOIL ECOLOGY DT Article AB The alpine meadow in the Qinghai-Tibetan Plateau has degraded in recent years; however, the response of soil macroinvertebrates to the alpine meadow degradation is unknown. We hypothesized that (i) soil macroinvertebrate diversity and abundance decrease gradually during alpine meadow degradation and (ii) the composition of soil macroinvertebrate communities is specific to particular degradation phases. We investigated the soil macroinvertebrates, plant communities and soil properties in a swampy meadow, grassland meadow, moderately degraded meadow and severely degraded meadow to test the hypotheses from April 2009 to October 2011. These areas represent four degradation phases of alpine meadows. The structure of the soil macroinvertebrate community in the moderately degraded meadow was notably different from that of the swampy meadow and the grassland meadow. Most of the macroinvertebrate groups disappeared from the severely degraded meadow. Taxonomic richness and abundance were significantly greater in the moderately degraded meadow and were significantly lower in the severely degraded meadow. Significant seasonal dynamics were only found for taxonomic richness in the moderately degraded meadow. Furthermore, the abundances of Polydesmida and Coleoptera differed significantly between the four habitats, but no significant seasonal changes were observed in the four habitats. The soil macroinvertebrate structures were influenced by the plant and soil variations, particularly the available soil P and K, the pH and vegetation heights, which changed significantly among the habitats. The soil macroinvertebrate taxonomic richness was also significantly correlated with the species richness, species coverage, vegetation height, aboveground biomass of the plant community, bulk density, organic matter, available soil N, P and K and pH. However, the abundances of the soil macroinvertebrate community and Polydesmida were only correlated with the available soil P and K, while Coleoptera was significantly correlated with all measured soil parameters, plant species richness and species coverage. Our results demonstrated that moderate and severe degradation in the alpine meadow have significant effects on the structure, diversity and abundance of soil macroinvertebrate communities, and the available soil P and K, pH and vegetation height are the determining factors. Our results also indicated that the soil macroinvertebrates in moderately degraded meadows will be more easily affected by climate changes in the future. (C) 2015 Elsevier B.V. All rights reserved. C1 [Wu, Pengfei; Zhang, Hongzhi; Wang, Yong] Southwest Univ Nationalities, Coll Life Sci & Technol, Chengdu 610041, Peoples R China. RP Wang, Y (通讯作者)，Southwest Univ Nationalities, Coll Life Sci & Technol, Chengdu 610041, Peoples R China. EM wupf@swun.cn; wangyong010101@swun.cn TC 22 Z9 32 PD JUN PY 2015 VL 90 BP 60 EP 67 DI 10.1016/j.apsoil.2015.02.006 UT WOS:000351691600008 DA 2023-03-23 ER PT J AU Su, XK Wu, Y Dong, SK Wen, L Li, YY Wang, XX AF Su Xu-kun Wu Yu Dong Shi-kui Wen Lu Li Yuan-yuan Wang Xue-xia TI Effects of grassland degradation and re-vegetation on carbon and nitrogen storage in the soils of the Headwater Area Nature Reserve on the Qinghai-Tibetan Plateau, China SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Both overgrazing and climate change contribute to grassland degradation in the alpine regions of China and negatively affect soil carbon and nitrogen pools. We quantified changes in soil organic carbon (SOC) and total nitrogen (TN) in black soil beach (BSB). We measured SOC and TN in severely degraded and non-degraded grasslands to calculate differences in carbon and nitrogen storage, and field survey results were extrapolated to the entire headwaters area of the Qinghai-Tibetan Plateau (36.3x10(5) km(2)) to determine SOC and TN losses from these grasslands. We also evaluated changes in SOC and TN in severely degraded grasslands that were artificially re-vegetated five, seven and nine years ago. Totally 92.43 Tg C and 7.08 Tg N were lost from the BSB in the headwater area, which was approximately 50% of the original C and N soil pools. Re-vegetation of the degraded grasslands in the headwater area would result in a gain of 32.71 Tg C in the soil after five years, a loss of 5.52 Tg C after seven years and an increase of 44.15 Tg C after nine years. The TN increased by 53.09% and 59.98% after five and nine years, respectively, while it decreased by 4.92% after seven years of re-vegetation. The results indicate that C and N stocks followed a "V" shaped pattern with re-vegetation time. Understanding plant-soil interactions during succession of artificially planting grassland ecosystems is essential for developing scientifically sound management strategies for the effectively re-vegetated BSB. C1 [Su Xu-kun; Wu Yu; Dong Shi-kui; Wen Lu; Li Yuan-yuan; Wang Xue-xia] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM suxukun@126.com; wuyu3366169@126.com; dongshikui@sina.com; wenlu5210@126.com; yuanyuanhaha1989@163.com; wxx0427@163.com TC 39 Z9 43 PD MAY PY 2015 VL 12 IS 3 BP 582 EP 591 DI 10.1007/s11629-014-3043-z UT WOS:000355429000005 DA 2023-03-23 ER PT J AU Wagner, B Liang, EY Li, XX Dulamsuren, C Leuschner, C Hauck, M AF Wagner, Bettina Liang, Eryuan Li, Xiaoxia Dulamsuren, Choimaa Leuschner, Christoph Hauck, Markus TI Carbon pools of semi-arid Picea crassifolia forests in the Qilian Mountains (north-eastern Tibetan Plateau) SO FOREST ECOLOGY AND MANAGEMENT DT Article AB The vast alpine grasslands of the Tibetan Plateau are lined by a belt of oroboreal coniferous forests in the transition zone to the Central Asian semi-deserts and deserts which may play important roles in the hydrology and biogeochemistry of the region. Many of these forests exist under semi-arid climates, are exposed to rapid climate warming and suffer from intensive human impact. We investigated the carbon stocks in biomass and soil in the Picea crassifolia (Qinghai spruce) forests of the Qilian Mountains, northeastern Tibetan Plateau. In 18 forest plots at 2600-2800 m elevation, we found ecosystem carbon stocks of 348 Mg C ha(-1) with carbon densities of 43 Mg C ha(-1) in the live and dead aboveground biomass, 12 Mg C ha(-1) in roots, 3 Mg C ha(-1) in litter and 305 Mg C ha(-1) in the soil (SOC; 0-100 cm). The below-ground carbon pools exceed averages reported for northern boreal forests and even more clearly for zonal forest vegetation in the temperate zone. The high SOC density in the P. crassifolia forests are probably the result of slow decomposition rates due to low soil temperatures in combination with low soil moisture. The widespread degradation of mountain spruce forests to shrubland reduces the ecosystem carbon stock by >85 Mg C ha(-1), and is partly caused by a 15%-reduction in SOC. We conclude that the remaining mountain forests of spruce and other conifers at the northern fringe of the Tibetan Plateau play an important role in the regional carbon budget and need urgent conservation. (C) 2015 Elsevier B.V. All rights reserved. C1 [Wagner, Bettina; Dulamsuren, Choimaa; Leuschner, Christoph; Hauck, Markus] Univ Gottingen, Albrecht von Haller Inst Plant Sci, Dept Plant Ecol, D-37073 Gottingen, Germany. [Liang, Eryuan; Li, Xiaoxia] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Key Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. RP Hauck, M (通讯作者)，Univ Gottingen, Albrecht von Haller Inst Plant Sci, Dept Plant Ecol, Untere Karspule 2, D-37073 Gottingen, Germany. EM mhauck@gwdg.de TC 28 Z9 29 PD MAY 1 PY 2015 VL 343 BP 136 EP 143 DI 10.1016/j.foreco.2015.02.001 UT WOS:000352246000014 DA 2023-03-23 ER PT J AU Yuan, H Hou, FJ AF Yuan, Hang Hou, Fujiang TI Grazing intensity and soil depth effects on soil properties in alpine meadow pastures of Qilian Mountain in northwest China SO ACTA AGRICULTURAE SCANDINAVICA SECTION B-SOIL AND PLANT SCIENCE DT Article AB In the mountainous rangeland of inland arid regions of Eurasia, seasonal grazing has been important to local communities for production of food, fiber, and for income, for the past thousand years. Recent population increases and other changes have put traditional grazing systems under pressure. However, empirical data describing soil properties or the impact of traditional grazing practice on the thresholds at which increase in animal stocking rate (SR) may result in degradation are lacking. Here, we provide, for alpine "typical steppe" at Qilian Mountain on the Tibetan plateau in China, a description of variation in some soil properties with soil depth, and with variation in grazing intensity. The soils studied have a humus-rich epipedon typically exceeding our sampling depth of 40 cm. As commonly reported, increased grazing intensity has correlated with depletion in soil organic carbon (SOC). Regression of our SOC data on SR indicated no "safe" threshold for grazing intensity below which SOC depletion would not occur. Other soil changes linked to increased grazing intensity in our study included a lowering of the carbon:nitrogen ratio (indicating possibly increased risk of nitrogen loss from farming systems to the wider environment), an increase in soil bulk density, a decrease in soil moisture content, and transfer of phosphorus from less intensively grazed areas toward animal night pens. Our study site is experiencing a climate warming trend which may be contributing to loss of SOC. C1 [Yuan, Hang] Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730020, Gansu, Peoples R China. [Hou, Fujiang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China. RP Hou, FJ (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Gansu, Peoples R China. EM cyhoufj@lzu.edu.cn TC 24 Z9 35 PD APR 3 PY 2015 VL 65 IS 3 BP 222 EP 232 DI 10.1080/09064710.2014.992940 UT WOS:000350385700003 DA 2023-03-23 ER PT J AU Yang, Y Wang, GX Klanderud, K Wang, JF Liu, GS AF Yang, Yan Wang, Genxu Klanderud, Kari Wang, Junfeng Liu, Guangsheng TI Plant community responses to five years of simulated climate warming in an alpine fen of the Qinghai-Tibetan Plateau SO PLANT ECOLOGY & DIVERSITY DT Article AB Background: Alpine and arctic ecosystems at high latitudes have been shown to be particularly vulnerable to climate change, but little has been reported about plant community responses from lower latitudes, such as the vast Qinghai-Tibetan Plateau. Aim: To examine how alpine fen plant community species richness, diversity, cover, above- and below-ground biomass, and how the abundance of two sedges, the dominant Kobresia tibetica and the subordinate Carex moorcroftii, respond to experimental warming. Methods: We used open-top chambers of two heights, with identical open-top area, to simulate two levels of experimental warming at 4700m on the Qinghai-Tibetan Plateau. Results: Five years of experimental warming reduced species richness and diversity, primarily due to a decrease in the diversity of graminoids. Above-ground biomass, vegetation height and cover increased at both levels of warming. Below-ground biomass increased at a depth of 5-20cm, but not at 0-5cm, indicating an allocation of resource to plant roots in deeper soils. Conclusion: The different responses to warming between the two graminoids in the study suggest that further studies on species-specific responses are needed to understand the regional differences observed in response to long-term warming. Our study also documented a decline in species richness and diversity in the control plots during the five-year experimental period which, together with results from other studies in this region, suggests that the alpine fens are already changing in response to the on-going climate warming in this area. C1 [Yang, Yan; Wang, Genxu; Liu, Guangsheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolvement & Regulat, Chengdu, Peoples R China. [Klanderud, Kari] Norwegian Univ Life Sci, Dept Ecol & Nat Resource Management, As, Norway. [Wang, Junfeng] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Frozen Soil Engn, Lanzhou, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolvement & Regulat, Chengdu, Peoples R China. EM wanggx@imde.ac.cn TC 18 Z9 22 PD MAR 4 PY 2015 VL 8 IS 2 BP 211 EP 218 DI 10.1080/17550874.2013.871654 UT WOS:000349789100002 DA 2023-03-23 ER PT J AU Dong, QM Zhao, XQ Wu, GL Chang, XF AF Dong, Quan-Ming Zhao, Xin-Quan Wu, Gao-Lin Chang, Xiao-Feng TI Optimization yak grazing stocking rate in an alpine grassland of Qinghai-Tibetan Plateau, China SO ENVIRONMENTAL EARTH SCIENCES DT Article AB A simple yak (Bos grunniens) production model developed in this study was to evaluate the health of the intensive livestock production system in the three rivers headwaters region, on the Qinghai-Tibetan Plateau. An experiment conducted for 3 years showed that individual yak liveweight gain (kg/head) was negatively related to stocking rate (Sr) (head/ha). Yak liveweight gain per hectare (kg/ha) was modeled as a quadratic function of Sr, with an apparent optimum yak stocking rate (Sr-op). Following the model, the Sr-op rate was 1.67 heads/ha for the warm-season pasture (WSP), 0.72 head/ha for the cool-season pasture (CSP), and 0.63 head/ha for the yearlong periods grazing pastures, respectively. The corresponding maximum carrying capacity (when individual yak live weight gain was equal to zero) was 3.34, 1.44, and 1.26 head/ha for warm-season, cool-season, and yearlong periods grazing pasture, respectively. In comparison with modeled maximum stock carrying capacity, all the cold-season pasture in the three rivers headwaters region were overgrazed. By contrast, only 37.5 % of the warm-season rangeland area overgrazed. It indicated that reconstruction of the proportion of the seasonal rangeland area may be an effective strategy to prevent serious rangeland degradation in this alpine region. Moreover, adjustment of the stoking rate at optimum values may likely improve the income for local herders. C1 [Dong, Quan-Ming] Qinghai Acad Anim & Vet Sci, Key Lab Alpine Grassland Ecosyst River Head Water, Xining 810016, Qinghai, Peoples R China. [Dong, Quan-Ming; Zhao, Xin-Quan] Chinese Acad Sci, Northwest Plateau Inst Biol, Xining 810003, Qinghai, Peoples R China. [Wu, Gao-Lin; Chang, Xiao-Feng] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. RP Zhao, XQ (通讯作者)，Chinese Acad Sci, Northwest Plateau Inst Biol, Xining 810003, Qinghai, Peoples R China. EM xqzhao@nwipb.cas.cn; gaolinwu@gmail.com TC 28 Z9 32 PD MAR PY 2015 VL 73 IS 5 BP 2497 EP 2503 DI 10.1007/s12665-014-3597-7 UT WOS:000349360600046 DA 2023-03-23 ER PT J AU Ingrisch, J Biermann, T Seeber, E Leipold, T Li, MS Ma, YM Xu, XL Miehe, G Guggenberger, G Foken, T Kuzyakov, Y AF Ingrisch, Johannes Biermann, Tobias Seeber, Elke Leipold, Thomas Li, Maoshan Ma, Yaoming Xu, Xingliang Miehe, Georg Guggenberger, Georg Foken, Thomas Kuzyakov, Yakov TI Carbon pools and fluxes in a Tibetan alpine Kobresia pygmaea pasture partitioned by coupled eddy-covariance measurements and (CO2)-C-13 pulse labeling SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB The Tibetan highlands host the largest alpine grassland ecosystems worldwide, bearing soils that store substantial stocks of carbon (C) that are very sensitive to land use changes. This study focuses on the cycling of photoassimilated C within a Kobresia pygmaea pasture, the dominating ecosystems on the Tibetan highlands. We investigated short-term effects of grazing cessation and the role of the characteristic Kobresia root turf on C fluxes and belowground C turnover. By combining eddy-covariance measurements with (CO2)-C-13 pulse labeling we applied a powerful new approach to measure absolute fluxes of assimilates within and between various pools of the plant-soil-atmosphere system. The roots and soil each store roughly 50% of the overall C in the system (76 Mg Cha(-1)), with only a minor contribution from shoots, which is also expressed in the root:shoot ratio of 90. During June and July the pasture acted as a weak C sink with a strong uptake of approximately 2 g C m(-2) d(-1) in the first half of July. The root turf was the main compartment for the turnover of photoassimilates, with a subset of highly dynamic roots (mean residence time 20 days), and plays a key role for the C cycling and C storage in this ecosystem. The short-term grazing cessation only affected aboveground biomass but not ecosystem scale C exchange or assimilate allocation into roots and soil. (C) 2014 Elsevier B.V. All rights reserved. C1 [Ingrisch, Johannes] Univ Bayreuth, Dept Agroecosyst Res, Bayreuth, Germany. [Biermann, Tobias; Leipold, Thomas; Foken, Thomas] Univ Bayreuth, Dept Micrometeorol, Bayreuth, Germany. [Seeber, Elke] Senckenberg Museum Nat Hist, Gorlitz, Germany. [Li, Maoshan] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou, Peoples R China. [Ma, Yaoming] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing, Peoples R China. [Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China. [Miehe, Georg] Univ Marburg, Fac Geog, Marburg, Germany. [Guggenberger, Georg] Leibniz Univ Hannover, Inst Soil Sci, D-30167 Hannover, Germany. [Foken, Thomas] Bayreuth Ctr Ecol & Ecosystem Res BayCEER, Bayreuth, Germany. [Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, D-37073 Gottingen, Germany. [Kuzyakov, Yakov] Univ Gottingen, Dept Agr Soil Sci, D-37073 Gottingen, Germany. [Kuzyakov, Yakov] Kazan Fed Univ, Inst Environm Sci, Kazan, Russia. RP Ingrisch, J (通讯作者)，Univ Innsbruck, Inst Ecol, Stemwartestr 15, A-6020 Innsbruck, Austria. EM johannes.ingrisch@uibk.ac.at TC 26 Z9 28 PD FEB 1 PY 2015 VL 505 BP 1213 EP 1224 DI 10.1016/j.scitotenv.2014.10.082 UT WOS:000347654900120 DA 2023-03-23 ER PT J AU Sun, FD Chen, WY Liu, L Liu, W Lu, CX Smith, P AF Sun, Feida Chen, Wenye Liu, Lin Liu, Wei Lu, Chengxiang Smith, Pete TI The density of active burrows of plateau pika in relation to biomass allocation in the alpine meadow ecosystems of the Tibetan Plateau SO BIOCHEMICAL SYSTEMATICS AND ECOLOGY DT Article AB Understanding the relationships between plateau pika population and plants biomass is essential for improving small herbivores management in alpine meadow ecosystems. Four degrees of active burrow densities were classified to evaluate pika populations and biomass allocation interactions. Our results showed that plant composition, overall vegetation height and cover, dominant species were significantly different among four sites. Additionally, plant functional groups, above ground, below ground and total biomass, root:shoot ratios and the living roots proportion were the greatest at the zero-density site, and those at the medium-density site were the lowest. We postulate that pika activities may not be the cause of the differences, but a symptom of grassland degradation. Further, pika population fluctuations should be monitored, and when the population exceeds the economic threshold of low-density (110 pikas or/and 512 active burrows ha(-1)) or reaches high-density (200 pikas or/and 1360 active burrows ha(-1)), integrated management strategies should be implemented to protect damage. (C) 2015 Elsevier Ltd. All rights reserved. C1 [Sun, Feida; Liu, Lin; Liu, Wei; Lu, Chengxiang] Sichuan Agr Univ, Coll Anim Sci & Technol, Dept Grassland Sci, Yaan 625014, Sichuan Provinc, Peoples R China. [Chen, Wenye] Gansu Forestry Sci & Technol Res Acad, Lanzhou 730020, Gansu Province, Peoples R China. [Smith, Pete] Univ Aberdeen, Inst Biol & Environm Sci, Aberdeen AB24 3UU, Scotland. RP Sun, FD (通讯作者)，Sichuan Agr Univ, Coll Anim Sci & Technol, Dept Grassland Sci, Yaan 625014, Sichuan Provinc, Peoples R China. EM sunfeida@sohu.com TC 22 Z9 31 PD FEB PY 2015 VL 58 BP 257 EP 264 DI 10.1016/j.bse.2014.12.016 UT WOS:000351320000037 DA 2023-03-23 ER PT J AU Wang, JS Wang, ZK Zhang, XZ Zhang, YJ Ran, CQ Zhang, JL Chen, BX Zhang, BS AF Wang, Jingsheng Wang, Zhikai Zhang, Xianzhou Zhang, Yangjian Ran, Congqian Zhang, Junlong Chen, Baoxiong Zhang, Bingsong TI Response of Kobresia pygmaea and Stipa purpurea Grassland Communities in Northern Tibet to Nitrogen and Phosphate Addition SO MOUNTAIN RESEARCH AND DEVELOPMENT DT Article AB The Tibetan Plateau is of fundamental ecological significance to China, Asia, and the world. In recent years, Tibetan grasslands have suffered from severe degradation due to climate change and anthropogenic disturbance. In this study, nitrogen (N) and phosphate were applied to a moderately degraded Kobresia pygmaea meadow and Stipa purpurea steppe in the arid alpine northern Tibetan Plateau. The results showed that with increasing nitrogenous fertilizer, the height, coverage, biomass, and importance value of the K. pygmaea population decreased whereas the population of S. purpurea exhibited the opposite trend. Application of a mixed fertilizer with the same amount of N and phosphorus (P) (5 g each per m(2)) doubled the biomass of the K. pygmaea meadow and increased the aboveground biomass of the S. purpurea steppe by 72.3%. The nitrogenous fertilizer increased the total biomass and belowground biomass of the S. purpurea steppe, whereas the mixed fertilizer was beneficial to aboveground grass recovery. Application of 10 g N + 5 g P m(-2) fertilizer increased aboveground biomass by 164.8%, whereas the belowground biomass was less than the control by 4.7%. The N and P fertilizer did not affect soil pH, except for some changes in soil N and P contents. C1 [Wang, Jingsheng; Zhang, Xianzhou; Zhang, Yangjian; Chen, Baoxiong; Zhang, Bingsong] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Wang, Jingsheng; Wang, Zhikai; Ran, Congqian; Zhang, Junlong] Renmin Univ China, Sch Environm & Nat Resources, Beijing 100872, Peoples R China. RP Zhang, XZ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. EM zhangxz@igsnrr.ac.cn TC 15 Z9 18 PD FEB PY 2015 VL 35 IS 1 BP 78 EP 86 DI 10.1659/MRD-JOURNAL-D-11-00104.1 UT WOS:000350990000009 DA 2023-03-23 ER PT J AU Zhou, ZY Yi, SH Chen, JJ Ye, BS Sheng, Y Wang, GX Ding, YJ AF Zhou, Zhaoye Yi, Shuhua Chen, Jianjun Ye, Baisheng Sheng, Yu Wang, Genxu Ding, Yongjian TI Responses of alpine grassland to climate warming and permafrost thawing in two basins with different precipitation regimes on the Qinghai-Tibetan Plateau SO ARCTIC ANTARCTIC AND ALPINE RESEARCH DT Article AB Alpine grassland and permafrost occupy about two thirds and one half of the total area of the Qinghai-Tibetan Plateau (QTP), respectively. Soil water, which can be affected by permafrost thawing and precipitation, is important for vegetation growth in this region. It is therefore vital to consider the effects of both thawing and precipitation when studying the effect of climate warming on alpine grassland on the QTP. In this study, we examined two adjacent basins, one semiarid and the other semihumid, in the northeastern section of the QTP. We used remote sensing data to compare fractional vegetation cover (FVC) and the relationships between FVC and land surface temperature (LST) in different types of frozen ground; the samples were analogous to a chronosequence of climate warming and permafrost thawing. Our analysis produced three significant results: (1) the FVCs of the semihumid basin were significantly greater than those of the semiarid basin for most types of frozen ground (p < 0.05); (2) the changes in FVC along the climate warming and permafrost thawing chronosequence were different in the two basins, with the maximum FVC occurring on the transition permafrost zone in the semiarid basin and on the seasonal frost zone in the semihumid basin; and (3) at the peak of the growing season, only the three warmest types of frozen ground in the semiarid basin had a negative relationship between FVC and LST, suggesting that vegetation growth was limited by water. Therefore, we concluded that the responses of alpine grassland to climate warming in the permafrost regions are complicated by precipitation and permafrost thawing; specifically, grasslands will not necessarily simply degrade as the climate warms, as suggested by previous plotscale studies. C1 [Zhou, Zhaoye] Lanzhou Univ Technol, Sch Civil Engn, Lanzhou 730050, Peoples R China. [Zhou, Zhaoye; Yi, Shuhua; Chen, Jianjun; Ye, Baisheng; Ding, Yongjian] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China. [Sheng, Yu] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. [Wang, Genxu] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. RP Yi, SH (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, 320 Donggang West Rd, Lanzhou 730000, Peoples R China. EM yis@lzb.ac.cn TC 26 Z9 27 PD FEB PY 2015 VL 47 IS 1 BP 125 EP 131 DI 10.1657/AAAR0013-098 UT WOS:000350219000011 DA 2023-03-23 ER PT J AU Shi, CG Silva, LCR Zhang, HX Zheng, QY Xiao, BX Wu, N Sun, G AF Shi, Changguang Silva, Lucas C. R. Zhang, Hongxuan Zheng, Qunying Xiao, Bingxue Wu, Ning Sun, Geng TI Climate warming alters nitrogen dynamics and total non-structural carbohydrate accumulations of perennial herbs of distinctive functional groups during the plant senescence in autumn in an alpine meadow of the Tibetan Plateau, China SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Although photoperiod is known to be the main factor driving plant senescence in perennial plants, temperature has also been shown to modulate this process, which suggests that climate warming will significantly impact the length of plant growing season and affect terrestrial productivity. To test this assumption, we measured the effects of simulated autumn warming on four perennial herbaceous species, i.e. Elymus nutans, Koeleria macrantha, Vicia unijuga and Allium atrosanguineum, representing two major plant functional groups (grasses and forbs), in a typical alpine meadow of the Tibetan Plateau. Warming was simulated using open-top chambers, and its effects on degradation of chlorophyll and nitrogen (N) concentration in leaves and stems were determined during the senescence processes in autumn. The potential effects of autumn warming on total non-structural carbohydrate (TNC) in roots, growth and flowering phenology were further investigated in the following year. We found that warming delayed chlorophyll degradation of perennial herbs in early phase but accelerated it in later phase, regardless of functional groups, which led to higher N concentrations in leaves and stems during the whole senescence period. Autumn warming also significantly increased TNC in roots as a result of the delayed process of chlorophyll degradation, although the magnitudes were dependent on functional groups, which may be explained by inherent differences in growth patterns and phenology between grasses and forbs. We demonstrate that warming can increase carbohydrate accumulation not only by enhancing activities of photosynthetic enzymes proved by many previous studies but by altering chlorophyll degradation and preferential allocation of resources to different compartments. Furthermore, these results suggest that the net effect of climate warming on terrestrial ecosystems will be determined by floristic composition, as contrasting immediate and lasting (one year) changes in nutrient use and carbon allocation in response to warming were observed among species. (C) 2014 Elsevier B.V. All rights reserved. C1 [Shi, Changguang; Wu, Ning; Sun, Geng] Chinese Acad Sci, Chengdu Inst Biol, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Peoples R China. [Shi, Changguang] Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat Biodivers Conservat Key Lab Sichuan, Chengdu 610041, Peoples R China. [Silva, Lucas C. R.] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Silva, Lucas C. R.] Univ Calif Davis, Biogeochem & Nutrient Cycling Lab, Davis, CA 95616 USA. [Zhang, Hongxuan; Zheng, Qunying; Xiao, Bingxue] Sichuan Acad Grassland Sci, Ctr Ecol Studies, Chengdu 611731, Peoples R China. [Wu, Ning] Int Ctr Integrated Mt Dev ICIMOD, Kathmandu, Nepal. RP Wu, N (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Peoples R China. EM wuning@cib.ac.cn; sungeng@cib.ac.cn TC 35 Z9 41 PD JAN 15 PY 2015 VL 200 BP 21 EP 29 DI 10.1016/j.agrformet.2014.09.006 UT WOS:000347582300003 DA 2023-03-23 ER PT J AU Dong, SK Sherman, R AF Dong, Shikui Sherman, Ruth TI Enhancing the resilience of coupled human and natural systems of alpine rangelands on the Qinghai-Tibetan Plateau SO RANGELAND JOURNAL DT Editorial Material AB This special issue covers a wide range of topics on the protection and sustainable management of alpine rangelands on the Qinghai-Tibetan Plateau (QTP), including Indigenous knowledge of sustainable rangeland management, science-policy interface for alpine rangeland biodiversity conservation, adaptations of local people to social and environmental changes and policy design for managing coupled human-natural systems of alpine rangelands. C1 [Dong, Shikui] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Dong, Shikui; Sherman, Ruth] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. TC 68 Z9 69 PY 2015 VL 37 IS 1 SI SI BP I EP III DI 10.1071/RJ14117 UT WOS:000349618400001 DA 2023-03-23 ER PT J AU Ganjurjav, H Duan, MJ Wan, YF Zhang, WN Gao, QZ Li, Y Jiangcun, WZ Danjiu, LB Guo, HB AF Ganjurjav, Hasbagan Duan, Min-jie Wan, Yun-fan Zhang, Wei-na Gao, Qing-zhu Li, Yue Jiangcun, Wang-zha Danjiu, Luo-bu Guo, Hong-bao TI Effects of grazing by large herbivores on plant diversity and productivity of semi-arid alpine steppe on the Qinghai-Tibetan Plateau SO RANGELAND JOURNAL DT Article AB Grazing by large herbivores may have a strong impact on plant diversity and productivity, but the effects are expected to vary with grazing pressure. The changes in productivity and species diversity of Stipa purpurea-dominated semi-arid alpine steppe grassland were measured under four different stocking rates of Tibetan sheep [no grazing, light (2.4 sheep units ha(-1)), moderate (3.6 sheep units ha(-1)), and heavy (6.0 sheep units ha(-1)) grazing] in a 5-year (2006-2010) grazing experiment on the Qinghai-Tibetan Plateau, China. Herbage mass and aboveground net primary productivity of alpine steppe declined significantly with increasing stocking rate (P < 0.05). Over the 5 years of the experiment, the proportion of forbs and sedges increased significantly under light and moderate grazing; the proportion of grasses decreased significantly, whereas the proportion of S. purpurea did not change compared with the no grazing treatment. Species diversity was highest under moderate grazing and was significantly higher than the no grazing treatment in 2 years (2008 and 2010). Moderate grazing enhanced the species diversity of the plant community due to an increase in the proportion of forbs. There were significant positive linear correlations between herbage mass and species diversity under no and light grazing. Species diversity was not related to productivity under moderate and heavy grazing. In conclusion, grazing by sheep reduced plant productivity; plant diversity increased under low and moderate grazing, and was as a result of changes in the composition of the plant community of a semi-arid alpine steppe. C1 [Ganjurjav, Hasbagan; Wan, Yun-fan; Zhang, Wei-na; Gao, Qing-zhu; Li, Yue] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Ganjurjav, Hasbagan; Wan, Yun-fan; Zhang, Wei-na; Gao, Qing-zhu; Li, Yue] Minist Agr, Key Lab Agroenvironm & Climate Change, Beijing 100081, Peoples R China. [Duan, Min-jie] Beijing Inst Landscape Architecture, Beijing 100102, Peoples R China. [Jiangcun, Wang-zha; Danjiu, Luo-bu; Guo, Hong-bao] Nagqu Agr & Anim Husb Bur, Nagqu 852100, Tibet Autonomou, Peoples R China. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM gaoqingzhu@caas.cn TC 14 Z9 15 PY 2015 VL 37 IS 4 BP 389 EP 397 DI 10.1071/RJ14127 UT WOS:000358664300006 DA 2023-03-23 ER PT J AU Guo, XW Du, YG Han, DR Xu, XL Zhang, FW Lin, L Li, YK Liu, SL Ouyang, JZ Cao, GM AF Guo, Xiaowei Du, Yangong Han, Daorui Xu, Xingliang Zhang, Fawei Lin, Li Li, Yikang Liu, Shuli Ouyang, Jingzheng Cao, Guangmin TI Effects of Landuse Change on CH4 Soil-Atmospheric Exchange in Alpine Meadow on the Tibetan Plateau SO POLISH JOURNAL OF ENVIRONMENTAL STUDIES DT Article AB Degradation of shrub meadows and reclamation of alpine meadows may heavily affect the soil sink for atmospheric methane (CH4), but this is poorly understood. Therefore, in situ measurements of atmospheric CH4 consumption were conducted in four landuse types: natural alpine meadow (NM), Elymus nutans pasture (EP), herbaceous meadow in shrub (HS), and a P. fruticosa shrub meadow (PS) within two years. CH4 fluxes were measured using static chambers and gas chromatography. All four types of land use showed atmospheric CH4 sink throughout the two years, with mean soil CH4 consumption rates at 24.6+/-10.9, 33.8+/-15.0, 39.8+/-10.3, and 28.1+/-12.1 mu g CH4.m(-2).hr(-1) for NM, EP, PS, and HS, respectively. Soil CH4 consumption increased by 40% by reclamation from NM to EP, while it decreased by 30% by degradation from PS to HS. Soil CH4 consumption in four types of land use was significantly correlated with temperature at 5 cm depth (P<0.01) and the soil water-filled pore space (WFPS) (P<0.05). Temperature showed stronger effects on soil CH4 consumption than WFPS, except in NM. UV radiation was positively correlated with soil CH4 consumption with increasing temperature and decreasing soil moisture. These findings indicate that a decrease in the grazing pressure in shrub meadows and increase in the area of artificial pasture reclaimed from alpine meadows would enhance the CH4 sink in alpine meadows on the Tibetan Plateau. C1 [Guo, Xiaowei; Du, Yangong; Zhang, Fawei; Lin, Li; Li, Yikang; Liu, Shuli; Ouyang, Jingzheng; Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Guo, Xiaowei; Han, Daorui; Liu, Shuli; Ouyang, Jingzheng] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100039, Peoples R China. [Han, Daorui; Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. RP Guo, XW (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. EM caogm@nwipb.cas.cn TC 6 Z9 6 PY 2015 VL 24 IS 4 BP 1593 EP 1602 DI 10.15244/pjoes/36181 UT WOS:000358899400014 DA 2023-03-23 ER PT J AU Li, YY Dong, SK Liu, SL Zhou, HK Gao, QZ Cao, GM Wang, XX Su, XK Zhang, Y Tang, L Zhao, HD Wu, XY AF Li, Yuanyuan Dong, Shikui Liu, Shiliang Zhou, Huakun Gao, Qingzhu Cao, Guangmin Wang, Xuexia Su, Xukun Zhang, Yong Tang, Lin Zhao, Haidi Wu, Xiaoyu TI Seasonal changes of CO2, CH4 and N2O fluxes in different types of alpine grassland in the Qinghai-Tibetan Plateau of China SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB Grassland degradation and grassland use type changes are associated with dynamics in soil properties and biogeochemical cycling, with implications for carbon and nitrogen cycling and trace gas fluxes. To examine the influence of grassland degradation and grassland use type changes on gases fluxes, emissions of CO2, CH4 and N2O were measured in three alpine ecosystems (alpine meadow, alpine steppe and alpine desert) with healthy and degraded grasslands on the Qinghai-Tibetan Plateau in May, August and October 2013. The lowest CO2, CH4 and N2O fluxes occurred in alpine deserts, and the highest fluxes occurred in alpine steppe. In general, degraded grasslands had relatively higher gas fluxes than healthy grasslands, except for CH4 dynamics. The temporal variation in gas fluxes indicated that CO2 and N2O fluxes were highest in August and lowest in May, while the lowest fluxes of CH4 were in August. Stepwise linear analysis was employed to explore the key factors for different gas fluxes. In alpine meadow and alpine steppe, the variation in CO2 and N2O fluxes in August could be explained by soil temperature and soil water content, while in May and October, soil physical and chemical properties, including soil pH, clay content and NO3--N, were the key factors. Soil water content and NH4+-N contributed to the CH4 fluxes. However, in alpine desert, soil water content was the key factor affecting gas emissions for different experimental sites. These results indicate that the examined alpine grasslands emitted a large amount of gas emissions especially after the grassland had degraded; therefore, more attention should be paid to protecting grassland degradation in the Qinghai-Tibetan Plateau. (C) 2014 Elsevier Ltd. All rights reserved. C1 [Li, Yuanyuan; Dong, Shikui; Liu, Shiliang; Wang, Xuexia; Su, Xukun; Zhang, Yong; Tang, Lin; Zhao, Haidi; Wu, Xiaoyu] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Zhou, Huakun; Cao, Guangmin] Chinese Acad Sci, Inst Northwest Biol, Xining 810003, Peoples R China. [Gao, Qingzhu] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 86 Z9 96 PD JAN PY 2015 VL 80 BP 306 EP 314 DI 10.1016/j.soilbio.2014.10.026 UT WOS:000346545800036 DA 2023-03-23 ER PT J AU Lin, L Li, YK Xu, XL Zhang, FW Du, YG Liu, SL Guo, XW Cao, GM AF Lin, L. Li, Y. K. Xu, X. L. Zhang, F. W. Du, Y. G. Liu, S. L. Guo, X. W. Cao, G. M. TI Predicting parameters of degradation succession processes of Tibetan Kobresia grasslands SO SOLID EARTH DT Article AB In the past two decades, increasing human activity (i.e., overgrazing) in the Tibetan Plateau has strongly influenced plant succession processes, resulting in the degradation of alpine grasslands. Therefore, it is necessary to diagnose the degree of degradation to enable implementation of appropriate management for sustainable exploitation and protection of alpine grasslands. Here, we investigated environmental factors and plant functional group (PFG) quantity factors during the alpine grassland succession processes. Principal component analysis (PCA) was used to identify the parameters indicative of degradation. We divided the entire degradation process into six stages. PFG types shifted from rhizome bunchgrasses to rhizome plexus and denseplexus grasses during the degradation process. Leguminosae and Gramineae plants were replaced by sedges during the advanced stages of degradation. The PFGs were classified into two reaction groups: the grazing-sensitive group, containing Kobresia humilis Mey, and Gramineae and Leguminosae plants, and the grazing-insensitive group, containing Kobresia pygmaea Clarke. The first group was correlated with live root biomass in the surface soil (0-10 cm), whereas the second group was strongly correlated with mattic epipedon thickness and K. pygmaea characteristics. The degree of degradation of alpine meadows may be delineated by development of mattic epipedon and PFG composition. Thus, meadows could be easily graded and their use adjusted based on our scaling system, which would help prevent irreversible degradation of important grasslands. Because relatively few environmental factors are investigated, this approach can save time and labor to formulate a conservation management plan for degraded alpine meadows. C1 [Lin, L.; Li, Y. K.; Zhang, F. W.; Du, Y. G.; Liu, S. L.; Guo, X. W.; Cao, G. M.] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810001, Peoples R China. [Xu, X. L.] Chinese Acad Sci, Inst Geog Sci & Nat Resources, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. RP Li, YK (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810001, Peoples R China. EM liyikang501@163.com; xuxingl@hotmail.com TC 49 Z9 57 PY 2015 VL 6 IS 4 BP 1237 EP 1246 DI 10.5194/se-6-1237-2015 UT WOS:000374540800010 DA 2023-03-23 ER PT J AU Liu, SL Zhao, HD Su, XK Deng, L Dong, SK Zhang, X AF Liu, S. L. Zhao, H. D. Su, X. K. Deng, L. Dong, S. K. Zhang, X. TI Spatio-temporal variability in rangeland conditions associated with climate change in the Altun Mountain National Nature Reserve on the Qinghai-Tibet Plateau over the past 15 years SO RANGELAND JOURNAL DT Article AB One of the focuses of global change research is on the impact of climate change on alpine vegetation. The Altun Mountain National Nature Reserve is the largest alpine desert rangeland reserve in China to protect wild endangered ungulate species. This paper aims to detect changing trends in rangeland conditions in this region. Temporal changes in the Normalised Difference Vegetation Index (NDVI) for the rangelands in the Altun Nature Reserve and its correlation with climatic variables were studied over the period from 1998 to 2012. Based on the NDVI index and using ArcGIS spatial analyst, the areas of likely rangeland degradation and areas of improved in rangeland condition were identified using linear regression analysis. The results showed that NDVI values were relatively low, varying from 0.04 to 0.1, and there existed distinct monthly changes. The highest NDVI values were exhibited in August. Generally, the NDVI showed an increasing trend over time with several annual fluctuations. High values were distributed mainly in the core area of the nature reserve. Trend analysis showed that vegetation near rivers and lakes was most likely to be degraded but, overall, the vegetation conditions improved over the 15 years of the study, which meant an improvement in the habitats of key wild ungulate species. Precipitation and temperature had a significant linear positive correlation with NDVI, which suggested that they were the main driving forces for rangeland improvement. The vegetation at the edge of the protected areas appeared degraded due to human activities. C1 [Liu, S. L.; Zhao, H. D.; Su, X. K.; Deng, L.; Dong, S. K.] Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China. [Zhang, X.] Nat Reserve Adm Altun Natl Nat Reserve, Kuerle 841000, Peoples R China. RP Liu, SL (通讯作者)，Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China. EM shiliangliu@bnu.edu.cn TC 23 Z9 23 PY 2015 VL 37 IS 1 SI SI BP 67 EP 75 DI 10.1071/RJ14068 UT WOS:000349618400008 DA 2023-03-23 ER PT J AU Liu, SL Su, XK Dong, SK Cheng, FY Zhao, HD Wu, XY Zhang, X Li, JR AF Liu, Shiliang Su, Xuku Dong, Shikui Cheng, Fangyan Zhao, Haidi Wu, Xiaoyu Zhang, Xiang Li, Junran TI Modeling aboveground biomass of an alpine desert grassland with SPOT-VGT NDVI SO GISCIENCE & REMOTE SENSING DT Article AB Grassland biomass on the Qinghai-Tibet Plateau is of great significance for the study of wildlife habitat and climate change. Based on Systeme Pour l'Observation de la Terre Vegetation normalized difference vegetation index (NDVI) data from 1998 to 2012 and a field survey investigation in 2013, we assessed aboveground biomass (AGB) dynamics in the Altun Mountain Nature Reserve. The results demonstrated that annual NDVI values varied greatly with an increasing trend. Areas of high- and medium-coverage grassland showed similar increasing trends. The NDVI-biomass relationship could be quantified by an exponential model and previous models over-estimated the amount of biomass in the alpine desert grassland. The total biomass was estimated to be 62 x 10(6) kg per year with large annual variations. No significant relationship was found between AGB and soil organic carbon contents, and the total grassland area (NDVI > 0.1) was positively correlated with the annual average temperature. C1 [Liu, Shiliang; Su, Xuku; Dong, Shikui; Cheng, Fangyan; Zhao, Haidi; Wu, Xiaoyu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Zhang, Xiang] Nat Reserve Adm Altun Natl Nat Reserve, Kuerle 841000, Peoples R China. [Li, Junran] Univ Tulsa, Dept Geosci, Tulsa, OK 74104 USA. RP Liu, SL (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM shiliangliu@bnu.edu.cn TC 20 Z9 21 PY 2015 VL 52 IS 6 BP 680 EP 699 DI 10.1080/15481603.2015.1080143 UT WOS:000369953700003 DA 2023-03-23 ER PT J AU Peng, F Quangang, Y Xue, X Guo, J Wang, T AF Peng, F. Quangang, Y. Xue, X. Guo, J. Wang, T. TI Effects of rodent-induced land degradation on ecosystem carbon fluxes in an alpine meadow in the Qinghai-Tibet Plateau, China SO SOLID EARTH DT Article AB The widespread land degradation in an alpine meadow ecosystem would affect ecosystem carbon (C) balance. Biomass, soil chemical properties and carbon dioxide (CO2) of six levels of degraded lands (D1-D6, according to the number of rodent holes and coverage) were investigated to examine the effects of rodent-induced land degradation on an alpine meadow ecosystem. Soil organic carbon (SOC), labile soil carbon (LC), total nitrogen (TN) and inorganic nitrogen (N) were obtained by chemical analysis. Soil respiration (R-s), net ecosystem exchange (NEE) and ecosystem respiration (ER) were measured by a Li-Cor 6400XT. Gross ecosystem production (GEP) was the sum of NEE and ER. Aboveground biomass (AGB) was based on a linear regression with coverage and plant height as independent variables. Root biomass (RB) was obtained by using a core method. Soil respiration, ER, GEP and AGB were significantly higher in slightly degraded (D3 and D6, group I) than in severely degraded land (D1, D2, D4 and D5, group II). Positive values of NEE average indicate that the alpine meadow ecosystem is a weak C sink during the growing season. The only significant difference was in ER among different degradation levels. R-s, ER and GEP were 38.2, 44.3 and 46.5% higher in group I than in group II, respectively. Similar difference of ER and GEP between the two groups resulted in an insignificant difference of NEE. Positive correlations of AGB with ER, NEE and GEP, and relatively small AGB and lower CO2 fluxes in group II, suggest the control of AGB on ecosystem CO2 fluxes. Correlations of RB with SOC, LC, TN and inorganic N indicate the regulation of RB on soil C and N with increasing number of rodent holes in an alpine meadow ecosystem in the permafrost region of the Qinghai-Tibet Plateau (QTP). C1 [Peng, F.; Quangang, Y.; Xue, X.; Guo, J.; Wang, T.] Chinese Acad Sci, Key Lab Desert & Desertificat, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou, Peoples R China. RP Xue, X (通讯作者)，Chinese Acad Sci, Key Lab Desert & Desertificat, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou, Peoples R China. EM xianxue@lzb.ac.cn TC 50 Z9 56 PY 2015 VL 6 IS 1 BP 303 EP 310 DI 10.5194/se-6-303-2015 UT WOS:000352161500022 DA 2023-03-23 ER PT C AU Sun, FD Chen, WY Lu, CX AF Sun, Fei-Da Chen, Wen-Ye Lu, Cheng-Xiang GP Destech Publicat Inc TI Plateau Pika Population Management in the Alpine Meadow Ecosystems of the Tibetan Plateau SO INTERNATIONAL CONFERENCE ON ENERGY AND ENVIRONMENT ENGINEERING (ICEEE 2015) DT Proceedings Paper CT International Conference on Energy and Environment Engineering (ICEEE) CY APR 11-12, 2015 CL Nanjing, PEOPLES R CHINA AB Understanding the impacts of the activities of plateau pikas on plants biomass and grassland degradation is essential for improving the management of pika populations in alpine meadow ecosystems. We defined four degrees with different active burrows densities within twelve survey sites to evaluate pika populations and biomass changes interactions. We conclude that pika activities may not be the cause of grassland degradation, but as a symptom of grassland degradation, while the high-frequency activities have triggered changes to reverse succession process. As such, a reduction of livestock numbers, a variable rotational grazing system, restorative management techniques, and community participation in co-management of the meadows are likely to effectively improve grassland productivity and deter pika outbreaks. Further, pika population fluctuations should be monitored, and when the population exceeds the economic threshold or reaches high-density, integrated management strategies should be implemented to protect damage. C1 [Sun, Fei-Da] Sichuan Agr Univ, Coll Anim Sci & Technol, Yaan 625014, Peoples R China. [Chen, Wen-Ye] Gansu Forestry Sci & Technol Res Acad, Lanzhou 730020, Peoples R China. [Lu, Cheng-Xiang] Sichuan Agr Univ, Coll Water Conservancy & Hydropower Engn, Yaan 625014, Peoples R China. RP Sun, FD (通讯作者)，Sichuan Agr Univ, Coll Anim Sci & Technol, Yaan 625014, Peoples R China. EM sunfd08@163.com; 442869815@qq.com; 414585379@qq.com TC 0 Z9 0 PY 2015 BP 597 EP 602 UT WOS:000352343500105 DA 2023-03-23 ER PT J AU Tang, L Dong, SK Sherman, R Liu, SL Liu, QR Wang, XX Su, XK Zhang, Y Li, YY Wu, Y Zhao, HD Zhao, C Wu, XY AF Tang, Lin Dong, Shikui Sherman, Ruth Liu, Shiliang Liu, Quanru Wang, Xuexia Su, Xukun Zhang, Yong Li, Yuanyuan Wu, Yu Zhao, Haidi Zhao, Chen Wu, Xiaoyu TI Changes in vegetation composition and plant diversity with rangeland degradation in the alpine region of Qinghai-Tibet Plateau SO RANGELAND JOURNAL DT Article AB The changes in vegetation composition and plant diversity of three different alpine ecosystems: alpine meadow, alpine steppe and alpine desert, impacted by different levels of degradation (healthy, lightly degraded and moderately degraded) were examined across a large-scale transect on the Qinghai-Tibet Plateau. The alpine meadow was dominated by sedges, the alpine steppe was dominated by grasses and the alpine desert was dominated by shrubs. The alpine meadow had the highest species diversity, whereas the alpine steppe had the lowest and tended to be dominated by a few species. Forbs were the dominant and most diverse functional group in the alpine meadow and the alpine steppe, which was different from the alpine desert. The importance values of the dominant species and levels of diversity measured by various vegetation indices were only slightly different in the degraded sites as compared with the non-degraded alpine meadow and steppe, whereas the alpine desert showed large changes in the composition and diversity of the plant community in response to degradation. In conclusion, the plant composition of the alpine meadow and alpine steppe ecosystems was more stable and appeared more resistant to disturbance than that of the alpine desert ecosystem. C1 [Tang, Lin; Dong, Shikui; Liu, Shiliang; Wang, Xuexia; Su, Xukun; Zhang, Yong; Li, Yuanyuan; Wu, Yu; Zhao, Haidi; Zhao, Chen; Wu, Xiaoyu] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Dong, Shikui; Sherman, Ruth] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. [Liu, Quanru] Beijing Normal Univ, Coll Life Sci, Beijing 100875, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 36 Z9 46 PY 2015 VL 37 IS 1 SI SI BP 107 EP 115 DI 10.1071/RJ14077 UT WOS:000349618400012 DA 2023-03-23 ER PT J AU Wang, CZ Guo, HD Zhang, L Liu, SY Qiu, YB Sun, ZC AF Wang, Cuizhen Guo, Huadong Zhang, Li Liu, Shuangyu Qiu, Yubao Sun, Zhongchang TI Assessing phenological change and climatic control of alpine grasslands in the Tibetan Plateau with MODIS time series SO INTERNATIONAL JOURNAL OF BIOMETEOROLOGY DT Article AB The Tibetan Plateau, a unique cold and dry region recognized as the Earth's third pole, is primarily composed of alpine grasslands (> 60 %). While a warming climate in the plateau is being recorded, phenology of alpine grasslands and its climatic dependencies are less investigated. This study tests the feasibility of the frequently observed Moderate Resolution Imaging Spectroradiometer (MODIS) time series (500 m, 8 days) in examining alpine phenology in the plateau. A set of phenological metrics are extracted from the MODIS Normalized Difference Vegetation Index (NDVI) series in each year, 2000-2010. A nonparametric Mann-Kendall trend analysis is performed to find the trends of these phenological metrics, which are then linked to monthly climatic records in the growing season. Opposite trends of phenological change are observed between the east and west of the plateau, with delayed start of season, peak date, and end of season in the west and advanced phenophases in the east. The correlation analysis indicates that precipitation, with a decreasing trend in the west and increasing trend in the east, may serve as the primary driver of the onset and peak dates of greenness. Temperature increases all over the plateau. While the delay of the end of season in the west could be related to higher late-season temperature, its advance in the east needs further investigation in this unique cold region. This study demonstrates that frequent satellite observations are able to extract phenological features of alpine grasslands and to provide spatiotemporally detailed base information for long-term monitoring on the plateau under rapid climate change. C1 [Wang, Cuizhen] Univ S Carolina, Dept Geog, Columbia, SC 29208 USA. [Guo, Huadong; Zhang, Li; Liu, Shuangyu; Qiu, Yubao; Sun, Zhongchang] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Beijing, Peoples R China. RP Wang, CZ (通讯作者)，Univ S Carolina, Dept Geog, Columbia, SC 29208 USA. EM cwang@mailbox.sc.edu; hdguo@ceode.ac.cn; lizhang@ceode.ac.cn; liushuangy2008@163.com; ybqiu@ceode.ac.cn; zcsun@ceode.ac.cn TC 54 Z9 57 PD JAN PY 2015 VL 59 IS 1 BP 11 EP 23 DI 10.1007/s00484-014-0817-5 UT WOS:000346637800002 DA 2023-03-23 ER PT J AU Wang, XX Dong, SK Sherman, R Liu, QR Liu, SL Li, YY Wu, Y AF Wang, Xuexia Dong, Shikui Sherman, Ruth Liu, Quanru Liu, Shiliang Li, Yuanyuan Wu, Yu TI A comparison of biodiversity-ecosystem function relationships in alpine grasslands across a degradation gradient on the Qinghai-Tibetan Plateau SO RANGELAND JOURNAL DT Article AB To examine biodiversity-ecosystem function relationships in alpine grasslands of the Qinghai-Tibetan Plateau, we compared differences in plant species and functional group diversity (sedges, grasses, legumes and non-leguminous forbs) to aboveground biomass, soil carbon (C) and nitrogen (N) pools and soil loss in five sites that ranged from healthy to severely degraded grasslands. Plant diversity decreased from 36 species in the healthy grassland to 15 species in the severely degraded grassland, and the plant functional groups changed from predominantly grasses and sedges to mostly forbs as the level of degradation increased. Plant biomass and soil pools of C and N decreased whereas soil loss and the amount of bare ground increased across the degradation gradient from healthy to severely degraded grasslands. Simple linear regressions showed strong positive relationships between species diversity and aboveground biomass of sedges, grasses and legumes and between soil C and N pools, but negative relationships between species diversity and non-leguminous forbs and soil loss. Our results provide strong evidence that plant diversity in grasslands on the Qinghai-Tibetan Plateau is positively related to primary productivity, C and N storage in soils and soil conservation, and that grassland degradation is impairing ecosystem function resulting in a loss in ecosystem services. C1 [Wang, Xuexia; Dong, Shikui; Liu, Shiliang; Li, Yuanyuan; Wu, Yu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Dong, Shikui; Sherman, Ruth] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. [Liu, Quanru] Beijing Normal Univ, Coll Life Sci, Beijing 100875, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 35 Z9 39 PY 2015 VL 37 IS 1 SI SI BP 45 EP 55 DI 10.1071/RJ14081 UT WOS:000349618400006 DA 2023-03-23 ER PT J AU Wu, QB Hou, YD Yun, HB Liu, YZ AF Wu Qingbai Hou Yandong Yun Hanbo Liu Yongzhi TI Changes in active-layer thickness and near-surface permafrost between 2002 and 2012 in alpine ecosystems, Qinghai-Xizang (Tibet) Plateau, China SO GLOBAL AND PLANETARY CHANGE DT Article AB Between 2002 and 2012, daily soil temperature measurements were made at 10 sites within five alpine ecosystems in the Beiluhe area of the central Qinghai-Tibet Plateau. Changes in freeze-thaw occurrence, active-layer thickness and near-surface permafrost temperature in barren, desert grassland, alpine steppe and alpine meadow ecosystems indicate that alpine ecosystems are sensitive to climate variability. During this time, the average onset of spring thawing at 50-cm depth advanced by at least 16 days in all but the barren alpine settings, and the duration of thaw increased by at least 14 days for all but the desert grassland and barren ecosystems. All sites showed an increase in active-layer thickness (ALT) and near-surface permafrost temperature: the average increase of ALT was similar to 4.26 cm/a and the average increase in permafrost temperatures at 6 m and 10 m depths were, respectively, similar to 0.13 degrees C and similar to 0.14 degrees C. No apparent trend in mean annual air temperature was detected at the Beiluhe weather station. However, an increasing trend in precipitation was measured. This suggests that the primary control on the ALT increase was an increase in summer rainfall and the primary control on increasing permafrost temperature was probably the combined effects of increasing rainfall and the asymmetrical seasonal changes in subsurface soil temperatures. (C) 2014 Elsevier B.V. All rights reserved. C1 [Wu Qingbai; Hou Yandong; Yun Hanbo; Liu Yongzhi] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Wu Qingbai; Yun Hanbo; Liu Yongzhi] Chinese Acad Sci, Beiluhe Observat Stn Frozen Soil Environm & Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Hou Yandong] Univ Chinese Acad Sci, Sch Resources & Environm, Beijing 100049, Peoples R China. RP Wu, QB (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. EM qbwu@lzbac.cn TC 149 Z9 167 PD JAN PY 2015 VL 124 BP 149 EP 155 DI 10.1016/j.gloplacha.2014.09.002 UT WOS:000349577800011 DA 2023-03-23 ER PT J AU Xu, HY Wu, XD Zhao, L Zhao, YG Wu, TH Hu, GJ Li, WP Ding, YJ AF Xu, Haiyan Wu, Xiaodong Zhao, Lin Zhao, Yuguo Wu, Tonghua Hu, Guojie Li, Wangping Ding, Yongjian TI CHANGES IN SOIL ENZYME ACTIVITIES UNDER DIFFERENT VEGETATION TYPES OF THE NORTHERN FRINGE OF THE PERMAFROST REGIONS IN THE QINGHAI-TIBETAN PLATEAU SO FRESENIUS ENVIRONMENTAL BULLETIN DT Article AB Soil enzyme activities play key roles in soil biochemical processes. Enzymes are sensitive to environmental changes. To investigate the effects of vegetation and permafrost on the soil quality in the Qinghai-Tibetan Plateau, this study examined the enzyme activities of invertase, amylase, catalase, polyphenol oxidase, urease, and alkaline phosphatase in the soils under different vegetation and permafrost conditions of the northern fringe of the permafrost regions in the Qinghai-Tibetan Plateau. In addition, 19 soil physio-chemical variables including moisture, bulk density, organic matter, total nitrogen (TN), phosphorus (P), total potassium (TK), and pH, were investigated. The results showed that the environmental variables and enzyme activities varied in the soils from the wet meadow to the meadow where permafrost exists. The soil from the alpine desert showed the lowest enzyme activity and the lowest organic matter content, whereas the soils from the alpine steppe showed some similarities with the meadow and the steppe. meadow. The statistical analyses demonstrated that the soil properties were greatly affected by the vegetation and the permafrost, and the enzyme activities were good indicators of soil quality. There were no obvious differences between the soils from the meadow and the wet meadow, which may indicate that the wet meadow ecosystems in this fringe area are more vulnerable than those of the continuous permafrost regions. C1 [Xu, Haiyan] Lanzhou Jiaotong Univ, Sch Environm & Municipal Engn, Lanzhou 730070, Peoples R China. [Xu, Haiyan; Wu, Xiaodong; Zhao, Lin; Wu, Tonghua; Hu, Guojie; Li, Wangping; Ding, Yongjian] Chinese Acad Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, State Key Lab Cryospher Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Zhao, Yuguo] Chinese Acad Sci, Inst Soil Sci, Nanjing 210008, Jiangsu, Peoples R China. RP Wu, XD (通讯作者)，Chinese Acad Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, State Key Lab Cryospher Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. EM wxd565@163.com TC 1 Z9 2 PY 2015 VL 24 IS 12C BP 4720 EP 4728 UT WOS:000367699500003 DA 2023-03-23 ER PT J AU Xu, YD Li, F Xu, C Luo, SH Chao, SJ Guo, Y Liu, CC Zhang, LB AF Xu, Yanda Li, Fen Xu, Cui Luo, Shanghua Chao, Shijun Guo, Yang Liu, Chengcheng Zhang, Linbo TI Quantitative assessment of the ecological impact of Chinese cordyceps collection in the typical production areas SO ECOSCIENCE DT Article AB Chinese cordyceps (or caterpillar fungus, Cordyceps sinensis), an expensive medicinal organism, is collected intensively every spring. It is concluded that over-collection has caused vegetation and soil degradation. However, most descriptions of the ecological impact of collection were qualitative and the impact on plant communities has not been quantified precisely. Collection plots and control plots were established in three counties on the Tibetan Plateau in order to measure impacts of collection on plant community composition. The results showed that due to Chinese cordyceps collection, species diversity expressed as the Shannon-Wiener indices significantly decreased by 10-13%, community dominance expressed as the Berger-Parker indices significantly increased by 17-32%, vegetation cover significantly decreased by 11-19% and aboveground biomass significantly decreased by 21-46%. However, root biomass did not change significantly, and only a few soil physical and chemical indicators in some plots changed significantly. Although Chinese cordyceps collection caused ecological degradation, the undisturbed plant roots and soil guarantee vegetation recovery. Aboveground biomass was the most sensitive variable to Chinese cordyceps collection, and could be used as the evaluation indicator in efforts of ecological protection and recovery. C1 [Xu, Yanda; Li, Fen; Luo, Shanghua; Guo, Yang; Liu, Chengcheng; Zhang, Linbo] Chinese Res Inst Environm Sci, State Key Lab Environm Criteria & Risk Assessment, Beijing 100012, Peoples R China. [Xu, Yanda; Li, Fen; Luo, Shanghua; Guo, Yang; Liu, Chengcheng; Zhang, Linbo] Chinese Res Inst Environm Sci, State Environm Protect Key Lab Reg Ecol Proc & Fu, Beijing 100012, Peoples R China. [Xu, Cui] Beijing Normal Univ, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Chao, Shijun] Environm Sci Res & Design Inst Qinghai Prov, Sci Res Dept, Xining 810007, Peoples R China. RP Zhang, LB (通讯作者)，Chinese Res Inst Environm Sci, State Key Lab Environm Criteria & Risk Assessment, Beijing 100012, Peoples R China.; Zhang, LB (通讯作者)，Chinese Res Inst Environm Sci, State Environm Protect Key Lab Reg Ecol Proc & Fu, Beijing 100012, Peoples R China. EM zhanglb@craes.org.cn TC 5 Z9 5 PY 2015 VL 22 IS 2-4 BP 167 EP 175 DI 10.1080/11956860.2016.1181516 UT WOS:000378164500008 DA 2023-03-23 ER PT J AU Zhang, Y Gao, QZ Dong, SK Liu, SL Wang, XX Su, XK Li, YY Tang, L Wu, XY Zhao, HD AF Zhang, Yong Gao, Qingzhu Dong, Shikui Liu, Shiliang Wang, Xuexia Su, Xukun Li, Yuanyuan Tang, Lin Wu, Xiaoyu Zhao, Haidi TI Effects of grazing and climate warming on plant diversity, productivity and living state in the alpine rangelands and cultivated grasslands of the Qinghai-Tibetan Plateau SO RANGELAND JOURNAL DT Article AB Overgrazing and climate warming may be important drivers of alpine rangeland degradation in the Qinghai-Tibetan Plateau (QTP). In this study, the effects of grazing and experimental warming on the vegetation of cultivated grasslands, alpine steppe and alpine meadows on the QTP were investigated. The three treatments were a control, a warming treatment and a grazing treatment and were replicated three times on each vegetation type. The warming treatment was applied using fibreglass open-top chambers and the grazing treatment was continuous grazing by yaks at a moderately high stocking rate. Both grazing and warming negatively affected vegetation cover. Grazing reduced vegetation height while warming increased vegetation height. Grazing increased but warming reduced plant diversity. Grazing decreased and warming increased the aboveground plant biomass. Grazing increased the preferred forage species in native rangelands (alpine steppe and alpine meadow), while warming increased the preferred forage species in the cultivated grassland. Grazing reduced the vegetation living state (VLS) of all three alpine grasslands by nearly 70%, while warming reduced the VLS of the cultivated grassland and the alpine steppe by 32% and 56%, respectively, and promoted the VLS of the alpine meadow by 20.5%. It was concluded that overgrazing was the main driver of change to the alpine grassland vegetation on the QTP. The findings suggest that grazing regimes should be adapted in order for them to be sustainable in a warmer future. C1 [Zhang, Yong; Dong, Shikui; Liu, Shiliang; Wang, Xuexia; Su, Xukun; Li, Yuanyuan; Tang, Lin; Wu, Xiaoyu; Zhao, Haidi] Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China. [Gao, Qingzhu] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM gaoqzh@ami.ac.cn; dongshikui@sina.com TC 81 Z9 93 PY 2015 VL 37 IS 1 SI SI BP 57 EP 65 DI 10.1071/RJ14080 UT WOS:000349618400007 DA 2023-03-23 ER PT J AU Niu, FJ He, JX Zhang, GS Liu, XM Liu, W Dong, MX Wu, FS Liu, YJ Ma, XJ An, LZ Feng, HY AF Niu, Fujun He, Junxia Zhang, Gaosen Liu, Xiaomei Liu, Wei Dong, Maoxing Wu, Fasi Liu, Yongjun Ma, Xiaojun An, Lizhe Feng, Huyuan TI Effects of enhanced UV-B radiation on the diversity and activity of soil microorganism of alpine meadow ecosystem in Qinghai-Tibet Plateau SO ECOTOXICOLOGY DT Article AB The effects of enhanced UV-B radiation on abundance, community composition and the total microbial activity of soil bacteria in alpine meadow ecosystem of Qinghai-Tibet Plateau were investigated. Traditional counting and 16S rRNA gene sequencing were used to investigate the culturable bacteria and their composition in soil, meanwhile the total microbial activity was measured by microcalorimetry. The population of soil culturable bacteria was slightly reduced with the enhanced UV-B radiation in both of the two depths, 2.46 x 10(6) CFU/g in upper layer (0-10 cm), 1.44 x 10(6) CFU/g in under layer (10-20 cm), comparing with the control (2.94 x 10(6) CFU/g in upper layer, 1.65 x 10(6) CFU/g in under layer), although the difference was not statistically significant (P > 0.05). However, the bacteria diversity decreased obviously due to enhanced UV-B, the number of species for upper layer was decreased from 20 to 13, and from 16 to 13 for the lower layer. The distribution of species was also quite different between the two layers. Another obvious decrease induced by enhanced UV-B radiation was in the total soil microbial activities, which was represented by the microbial growth rate constant (k) in this study. The results indicated that the culturable bacteria community composition and the total activity of soil microbes have been considerably changed by the enhanced UV-B radiation. C1 [Niu, Fujun; Zhang, Gaosen] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. [He, Junxia; Liu, Xiaomei; Liu, Wei; Dong, Maoxing; Wu, Fasi; Liu, Yongjun; Ma, Xiaojun; An, Lizhe; Feng, Huyuan] Lanzhou Univ, Sch Life Sci, MOE Key Lab Cell Activ & Stress Adaptat, Lanzhou 730000, Peoples R China. RP Feng, HY (通讯作者)，Lanzhou Univ, Sch Life Sci, MOE Key Lab Cell Activ & Stress Adaptat, Lanzhou 730000, Peoples R China. EM fenghy@lzu.edu.cn TC 6 Z9 10 PD DEC PY 2014 VL 23 IS 10 SI SI BP 1833 EP 1841 DI 10.1007/s10646-014-1314-7 UT WOS:000345034000003 DA 2023-03-23 ER PT J AU Xue, ZS Zhang, ZS Lu, XG Zou, YC Lu, YL Jiang, M Tong, SZ Zhang, K AF Xue, Zhenshan Zhang, Zhongsheng Lu, Xianguo Zou, Yuanchun Lu, Yonglei Jiang, Ming Tong, Shouzheng Zhang, Kun TI Predicted areas of potential distributions of alpine wetlands under different scenarios in the Qinghai-Tibetan Plateau, China SO GLOBAL AND PLANETARY CHANGE DT Article AB Wetlands are vulnerable ecosystems to climate change for they would normally adapt slowly to keep pace with changing environmental conditions especially wetlands located at high altitudes which are under threat of severe warming. In this paper, we used distribution data of four types of wetlands in the Qinghai-Tibetan Plateau (QTP) and ensemble habitat distribution models (HDMs) to assess the potential impacts of climate change under three IPCC scenarios. The baseline year was 2000s and the scenarios were used for 3 periods (2020s, 2050s and 2080s) at a spatial resolution of 1 x 1 km. The simulation results show that severe warming will happen in mid-21st century and annual average temperature will be above 0 degrees C. Areas climatically suitable for alpine wetlands tend to shift and shrink generally in the QTP in the future. Even under the optimistic scenario, the total area of wetland is predicted to decline by 35.7%. Nearly all wet meadow and saltmarsh will disappear under all scenarios in the Qiangtang basin. Vital functions of alpine wetlands such as carbon sequestration, water maintain, and habitats provide will be at severe risk. This research provides valuable information for the future conservation of the alpine wetlands within the QTP. (C) 2014 Elsevier B.V. All rights reserved. C1 [Xue, Zhenshan; Zhang, Zhongsheng; Lu, Xianguo; Zou, Yuanchun; Jiang, Ming; Tong, Shouzheng] Chinese Acad Sci, Northeast Inst Geog & Agroecol, Key Lab Wetland Ecol & Environm, Changchun 130102, Peoples R China. [Lu, Yonglei] Forestry Dept Tibet, Inst Tibetan Forestry Survey & Planning, Lhasa 850000, Peoples R China. [Zhang, Kun] Southwest Forestry Univ, Natl Plateau Wetlands Res Ctr, Kunming 650224, Peoples R China. RP Lu, XG (通讯作者)，Chinese Acad Sci, Northeast Inst Geog & Agroecol, Key Lab Wetland Ecol & Environm, Changchun 130102, Peoples R China. TC 30 Z9 35 PD DEC PY 2014 VL 123 BP 77 EP 85 DI 10.1016/j.gloplacha.2014.10.012 PN A UT WOS:000347592300008 DA 2023-03-23 ER PT J AU Wei, D Xu-Ri Liu, YW Wang, YH Wang, YS AF Wei, Da Xu-Ri Liu, Yongwen Wang, Yinghong Wang, Yuesi TI Three-year study of CO2 efflux and CH4/N2O fluxes at an alpine steppe site on the central Tibetan Plateau and their responses to simulated N deposition SO GEODERMA DT Article AB The alpine steppe covers 700,000 km(2) on the central and western Tibetan Plateau, constituting a large portion of China's total grassland ecosystem. Yet, limited effort has been made to quantify its greenhouse gas fluxes and examine how they will respond to increased reactive N deposition. Therefore, we conducted an experiment to simulate an elevated level of N deposition (10 kg N ha(-1) a(-1)) to investigate the variability in GHG fluxes and their responses to the N treatment. Three years of measurements showed that: (1) CO2 efflux was 132.7 +/- 20.1 mg m(-2) h(-1) during the growing season, while CH4 uptake was -60.0 +/- 7.1 mu g m(-2) h(-1). The alpine steppe acted as a weak source of N2O (0.14 +/- 038 mu g m(-2) h(-1)), but neither soil moisture nor temperature explained its variation. (2) Simulated N deposition significantly enhanced the plant community in the alpine steppe in terms of leaf tissue N content. However, neither the seasonal pattern nor the CO2 efflux and CH4 uptake were significantly affected by the N additions, and the emission factors (EFs) of N2O varied from 0.16 to 0.85% (0.56 +/- 020%). Our consecutive observations quantify the alpine steppe ecosystem of the Tibetan Plateau as a vital CH4 sink. The lower EFs of N2O in the simulated N deposition experiment confirm previous measurements at temperate grassland sites in China, implying a potential overestimation of N2O emissions based on the IPCC default. (C) 2014 Elsevier B.V. All rights reserved. C1 [Wei, Da; Xu-Ri; Liu, Yongwen] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing, Peoples R China. [Liu, Yongwen] Univ Chinese Acad Sci, Beijing, Peoples R China. [Wang, Yinghong; Wang, Yuesi] Chinese Acad Sci, Inst Atmospher Phys, Beijing, Peoples R China. RP Xu-Ri (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Bldg 3,Courtyard 16,Lin Cui Rd, Beijing, Peoples R China. EM xu-ri@itpcas.ac.cn TC 47 Z9 51 PD NOV PY 2014 VL 232 BP 88 EP 96 DI 10.1016/j.geoderma.2014.05.002 UT WOS:000340315700010 DA 2023-03-23 ER PT J AU Wu, JS Zhang, XZ Shen, ZX Shi, PL Yu, CQ Chen, BX AF Wu, Jianshuang Zhang, Xianzhou Shen, Zhenxi Shi, Peili Yu, Chengqun Chen, Baoxiong TI Effects of livestock exclusion and climate change on aboveground biomass accumulation in alpine pastures across the Northern Tibetan Plateau SO CHINESE SCIENCE BULLETIN DT Article AB To better understand the ecological and economic benefits of short-term grazing exclusion on the aboveground net primary productivity (ANPP) of alpine pastures, we conducted annual multi-site transect surveys in the summers from 2009 to 2011 and calculated the aboveground biomass discrepancy (ABD) between grazed and ungrazed pastures at plant community and economic group levels for three zonal alpine grassland types-meadow, steppe, and desert-steppe-across the northern Tibetan Plateau. Our results indicated that aboveground biomass (AGB) significantly differed among grassland types and declined northwesterly from 64.07 to 11.44 g m(-2) with decreasing precipitation and increasing temperature. The mean ABD exhibited considerable community dependency, with meadow (12.47 g m(-2)) > steppe (6.91 g m(-2)) > desert steppe (2.54 g m(-2)), and it declined from 25.42 to 1.29 g m(-2) with decreasing precipitation and increasing temperature. 'Good forage', i.e. grasses and sedges, benefited most from grazing exclusion, followed by edible forbs. With longer grazing exclusion durations (GEDs), the aboveground biomass of poisonous locoweeds initially decreased and then increased compared with the adjacent grazed sites. In the nested analysis of co-variances with a general linear model, growing season precipitation (GSP; from May to September) accounted for 52.67% of the observed variation in AGB, followed by AGT (9.77 %) and pasture management systems (PMSs; grazing or grazing-excluded, 5.31 %). The variation in ABD was explained primarily by AGT (16.52 %), GED (20.25 %), and the interaction of AGT x GED (19.58 %). Our results confirm that precipitation is the primary factor controlling the ANPP of alpine grasslands on the Northern Tibetan Plateau and that the ecological benefits arising from grazing exclusion are also partly dependent on grassland type and exclusion duration. Therefore, spatial and temporal variations in growing season precipitation and plant functional traits or economic group composition should be jointly considered when developing policies concerning the management and spatial layouts of grazing exclosures in this region. C1 [Wu, Jianshuang; Zhang, Xianzhou; Shen, Zhenxi; Shi, Peili; Yu, Chengqun; Chen, Baoxiong] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. [Chen, Baoxiong] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Zhang, XZ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. EM zhangxz@igsnrr.ac.cn TC 29 Z9 37 PD NOV PY 2014 VL 59 IS 32 BP 4332 EP 4340 DI 10.1007/s11434-014-0362-y UT WOS:000342451800019 DA 2023-03-23 ER PT J AU Leipe, C Demske, D Tarasov, PE Wunnemann, B Riedel, F AF Leipe, Christian Demske, Dieter Tarasov, Pavel E. Wuennemann, Bernd Riedel, Frank CA HIMPAC Project Members TI Potential of pollen and non-pollen palynomorph records from Tso Moriri (Trans-Himalaya, NW India) for reconstructing Holocene limnology and human-environmental interactions SO QUATERNARY INTERNATIONAL DT Article AB The high-altitude lake Tso Moriri (32 degrees 55'46 '' N, 78 degrees 19'24 '' E; 4522 m a.s.l.) is situated at the margin of the Indian Summer Monsoon and westerly influences in the Trans-Himalayan region of Ladakh. Human settlements are rare and domestic and wild animals are concentrated in the alpine meadows. A set of modern surface samples and fossil pollen from a deep-water core was evaluated with focus on indicator types revealing human impact, grazing activities and lake system development during the last ca. 12 cal ka BP. The non-pollen palynomorph (NPP) record, comprising remains of limnic algae and invertebrates as well as fungal spores and charred plant tissue fragments, were examined in order to attest palaeolimnic phases and human impact, respectively. Changes in the early and middle Holocene limnic environment are mainly influenced by regional climatic conditions and glacier-fed meltwater flow in the catchment area. The NPP record indicates low lake productivity with high influx of freshwater between ca. 11.5 and 4.5 cal ka BP which is in agreement with the regional monsoon dynamics and published climate reconstructions. Geomorphologic observations suggest that during this period of enhanced precipitation the lake had a regular outflow and contributed large amounts of water to the Sutlej River, the lower reaches of which were integral part of the Indus Civilisation area. The inferred minimum freshwater input and maximum lake productivity between ca. 4.5-1.8 cal ka BP coincides with the reconstruction of greatest aridity and glaciation in the Korzong Valley, resulting in significantly reduced or even ceased outflow. We suggest that lowered lake levels and river discharge at a larger regional scale may have caused irrigation problems and harvest losses in the Indus Valley and lowlands occupied by sedentary agricultural communities. This scenario, in turn, supports the hypothesis that Mature Harappan urbanism(ca. 4.5-3.9 cal ka BP) emerged in order to facilitate storage, protection, administration, and redistribution of crop yields, and secondly, the eventual decline of the Harappan Culture (ca. 3.5-3 cal ka BP) was promoted by prolonged aridity. There is no clear evidence for human impact around Tso Moriri prior to ca. 3.7 cal ka BP, with a more distinct record since ca. 2.7 cal ka BP. This suggests that the sedimentary record from Tso Moriri primarily archives the regional climate history. (C) 2014 Elsevier Ltd and INQUA. All rights reserved. C1 [Leipe, Christian; Demske, Dieter; Tarasov, Pavel E.; Riedel, Frank] Free Univ Berlin, Inst Geol Sci, D-12249 Berlin, Germany. [Wuennemann, Bernd] Free Univ Berlin, Inst Geog Sci, D-12249 Berlin, Germany. [Wuennemann, Bernd] Nanjing Univ, Sch Geog & Oceanog Sci, Nanjing, Peoples R China. RP Leipe, C (通讯作者)，Free Univ Berlin, Inst Geol Sci, Malteserstr 74-100,Bldg D, D-12249 Berlin, Germany. EM c.leipe@fu-berlin.de TC 47 Z9 48 PD OCT 20 PY 2014 VL 348 BP 113 EP 129 DI 10.1016/j.quaint.2014.02.026 UT WOS:000344237300009 DA 2023-03-23 ER PT J AU Chu, HJ Wang, SP Yue, HW Lin, QY Hu, YG Li, XZ Zhou, JZ Yang, YF AF Chu, Houjuan Wang, Shiping Yue, Haowei Lin, Qiaoyan Hu, Yigang Li, Xiangzhen Zhou, Jizhong Yang, Yunfeng TI Contrasting soil microbial community functional structures in two major landscapes of the Tibetan alpine meadow SO MICROBIOLOGYOPEN DT Article AB The grassland and shrubland are two major landscapes of the Tibetan alpine meadow, a region very sensitive to the impact of global warming and anthropogenic perturbation. Herein, we report a study showing that a majority of differences in soil microbial community functional structures, measured by a functional gene array named GeoChip 4.0, in two adjacent shrubland and grassland areas, were explainable by environmental properties, suggesting that the harsh environments in the alpine grassland rendered niche adaptation important. Furthermore, genes involved in labile carbon degradation were more abundant in the shrubland than those of the grassland but genes involved in recalcitrant carbon degradation were less abundant, which was conducive to long-term carbon storage and sequestration in the shrubland despite low soil organic carbon content. In addition, genes of anerobic nitrogen cycling processes such as denitrification and dissimilatory nitrogen reduction were more abundant, shifting soil nitrogen cycling toward ammonium biosynthesis and consequently leading to higher soil ammonium contents. We also noted higher abundances of stress genes responsive to nitrogen limitation and oxygen limitation, which might be attributed to low total nitrogen and higher water contents in the shrubland. Together, these results provide mechanistic knowledge about microbial linkages to soil carbon and nitrogen storage and potential consequences of vegetation shifts in the Tibetan alpine meadow. C1 [Chu, Houjuan; Yue, Haowei; Zhou, Jizhong; Yang, Yunfeng] Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100084, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, Beijing 100085, Peoples R China. [Lin, Qiaoyan; Hu, Yigang] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adapt & Evolut Plateau Biota, Xining 810008, Peoples R China. [Hu, Yigang] Chinese Acad Sci, Cold & Arid Reg & Environm & Engn Res Inst, Shapotou Desert Expt & Res Stn, Lanzhou 730000, Peoples R China. [Li, Xiangzhen] Chengdu Inst Biol, Chinese Acad Sci, Chengdu 610041, Peoples R China. [Zhou, Jizhong] Univ Oklahoma, Inst Environm Genom, Norman, OK 73019 USA. [Zhou, Jizhong] Univ Oklahoma, Dept Bot & Microbiol, Norman, OK 73019 USA. [Zhou, Jizhong] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Yang, YF (通讯作者)，Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100084, Peoples R China. EM yangyf@tsinghua.edu.cn TC 11 Z9 15 PD OCT PY 2014 VL 3 IS 5 BP 585 EP 594 DI 10.1002/mbo3.190 UT WOS:000343761600001 DA 2023-03-23 ER PT J AU Tasumi, M Hirakawa, K Hasegawa, N Nishiwaki, A Kimura, R AF Tasumi, Masahiro Hirakawa, Kiyomi Hasegawa, Nobumi Nishiwaki, Aya Kimura, Rikako TI Application of MODIS Land Products to Assessment of Land Degradation of Alpine Rangeland in Northern India with Limited Ground-Based Information SO REMOTE SENSING DT Article AB Land degradation of alpine rangeland in Dachigam National Park, Northern India, was evaluated in this study using MODerate resolution Imaging Spectroradiometer (MODIS) land products. The park has been used by a variety of livestock holders. With increasing numbers of livestock, the managers and users of the park are apprehensive about degradation of the grazing land. However, owing to weak infrastructure for scientific and statistical data collection and sociopolitical restrictions in the region, a lack of quality ground-based weather, vegetation, and livestock statistical data had prevented scientific assessment. Under these circumstances, the present study aimed to assess the rangeland environment and its degradation using MODIS vegetation, snow, and evapotranspiration products as primary input data for assessment. The result of the analysis indicated that soil water content and the timing of snowmelt play an important role in grass production in the area. Additionally, the possibility of land degradation in heavily-grazed rangeland was indicated via a multiple regression analysis at a decadal timescale, whereas weather conditions, such as rainfall and snow cover, primarily explained year-by-year differences in grass production. Although statistical uncertainties remain in the results derived in this study, the satellite-based data and the analyses will promote understanding of the rangeland environment and suggest the potential for unsustainable land management based on statistical probability. This study provides an important initial evaluation of alpine rangeland, for which ground-based information is limited. C1 [Tasumi, Masahiro; Hirakawa, Kiyomi; Hasegawa, Nobumi; Nishiwaki, Aya] Miyazaki Univ, Fac Agr, Miyazaki 8892192, Japan. [Kimura, Rikako] Tokyo Univ Agr, Sci Informat Program, Setagaya Ku, Tokyo 1568502, Japan. RP Tasumi, M (通讯作者)，Miyazaki Univ, Fac Agr, 1-1 Gakuen Kibanadai Nishi, Miyazaki 8892192, Japan. EM tasumi@cc.miyazaki-u.ac.jp; nikujuu400@gmail.com; nhasegaw@cc.miyazaki-u.ac.jp; nishiwaki@cc.miyazaki-u.ac.jp; r3kimura@nodai.ac.jp TC 10 Z9 11 PD OCT PY 2014 VL 6 IS 10 BP 9260 EP 9276 DI 10.3390/rs6109260 UT WOS:000344458000006 DA 2023-03-23 ER PT J AU Wang, XX Dong, SK Yang, B Li, YY Su, XK AF Wang, Xuexia Dong, Shikui Yang, Bing Li, Yuanyuan Su, Xukun TI The effects of grassland degradation on plant diversity, primary productivity, and soil fertility in the alpine region of Asia's headwaters SO ENVIRONMENTAL MONITORING AND ASSESSMENT DT Article AB A 3-year survey was conducted to explore the relationships among plant composition, productivity, and soil fertility characterizing four different degradation stages of an alpine meadow in the source region of the Yangtze and Yellow Rivers, China. Results showed that plant species diversity, productivity, and soil fertility of the top 30-cm soil layer significantly declined with degradation stages of alpine meadow over the study period. The productivity of forbs significantly increased with degradation stages, and the soil potassium stock was not affected by grassland degradation. The vegetation composition gradually shifted from perennial graminoids (grasses and sedges) to annual forbs along the degradation gradient. The abrupt change of response in plant diversity, plant productivity, and soil nutrients was demonstrated after heavy grassland degradation. Moreover, degradation can indicate plant species diversity and productivity through changing soil fertility. However, the clear relationships are difficult to establish. In conclusion, degradation influenced ecosystem function and services, such as plant species diversity, productivity, and soil carbon and nitrogen stocks. Additionally, both plant species diversity and soil nutrients were important predictors in different degradation stages of alpine meadows. To this end, heavy degradation grade was shown to cause shift of plant community in alpine meadow, which provided an important basis for sustaining ecosystem function, manipulating the vegetation composition of the area and restoring the degraded alpine grassland. C1 [Wang, Xuexia; Dong, Shikui; Li, Yuanyuan; Su, Xukun] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Yang, Bing] Chinese Acad Sci, Chengdu Inst Biol, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu 610041, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 59 Z9 74 PD OCT PY 2014 VL 186 IS 10 BP 6903 EP 6917 DI 10.1007/s10661-014-3898-z UT WOS:000341497800068 DA 2023-03-23 ER PT J AU You, QY Xue, X Peng, F Xu, MH Duan, HC Dong, SY AF You, QuanGang Xue, Xian Peng, Fei Xu, Manhou Duan, Hanchen Dong, Siyang TI Comparison of ecosystem characteristics between degraded and intact alpine meadow in the Qinghai-Tibetan Plateau, China SO ECOLOGICAL ENGINEERING DT Article AB Climate warming and overgrazing are inducing degradation of the alpine meadow ecosystem on the Qinghai-Tibetan Plateau. The Plateau is an important pastoral region in China and controversy surrounds the estimated carbon release occurring in this region of the world. Nevertheless, little comprehensive research analyzing land degradation has been conducted involving multiple factors in this region. Usingtwo years of observational data, we compared differences in air temperature and relative humidity, soil temperature and moisture, soil texture, soil bulk density, soil organic carbon, soil respiration, vegetation height, coverage and biodiversity, above- and below ground biomass between moderately degraded and intact alpine meadow, and analyzed their relationships. The results show that the main process occurring during degradation was that Spenceria species and weeds with deep roots and a relatively high ability to resist drought replaced Kobresia species that previously exhibited high vegetation coverage and low vegetation height in alpine meadows of the Qinghai-Tibetan Plateau; these changes fundamentally affected corresponding changes in soil physical, chemical and thermal characteristics of the meadows. The change of vegetation species is believed to be the result of drought in the shallow soil of this habitat and is controlled by temperature and precipitation. The results suggest that a good collocation between temperature and precipitation is beneficial to the development of the alpine meadows; conversely, a poor pairing of temperature and precipitation not only causes the degradation of alpine meadows, it can even continually intensify the process by creating a vicious circle involving changes in soil physical, chemical, thermal and hydraulic conditions. (C) 2014 Elsevier B.V. All rights reserved. C1 [You, QuanGang; Xue, Xian; Peng, Fei; Xu, Manhou; Duan, Hanchen; Dong, Siyang] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Key Lab Desert & Desertificat, Lanzhou 730000, Peoples R China. RP Xue, X (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Key Lab Desert & Desertificat, 320 West Donggang Rd, Lanzhou 730000, Peoples R China. EM youqg@lzb.ac.cn; xianxue@lzb.ac.cn; pengguy02@yahoo.com; xumanhou@163.com; duanhanchen09@163.com; paula859@163.com TC 39 Z9 50 PD OCT PY 2014 VL 71 BP 133 EP 143 DI 10.1016/j.ecoleng.2014.07.022 UT WOS:000343151000019 DA 2023-03-23 ER PT J AU Shi, CG Sun, G Zhang, HX Xiao, BX Ze, B Zhang, NN Wu, N AF Shi, Changguang Sun, Geng Zhang, Hongxuan Xiao, Bingxue Ze, Bai Zhang, Nannan Wu, Ning TI Effects of Warming on Chlorophyll Degradation and Carbohydrate Accumulation of Alpine Herbaceous Species during Plant Senescence on the Tibetan Plateau SO PLOS ONE DT Article AB Plant senescence is a critical life history process accompanied by chlorophyll degradation and has large implications for nutrient resorption and carbohydrate storage. Although photoperiod governs much of seasonal leaf senescence in many plant species, temperature has also been shown to modulate this process. Therefore, we hypothesized that climate warming would significantly impact the length of the plant growing season and ultimate productivity. To test this assumption, we measured the effects of simulated autumn climate warming paradigms on four native herbaceous species that represent distinct life forms of alpine meadow plants on the Tibetan Plateau. Conditions were simulated in open-top chambers (OTCs) and the effects on the degradation of chlorophyll, nitrogen (N) concentration in leaves and culms, total non-structural carbohydrate (TNC) in roots, growth and phenology were assessed during one year following treatment. The results showed that climate warming in autumn changed the senescence process only for perennials by slowing chlorophyll degradation at the beginning of senescence and accelerating it in the following phases. Warming also increased root TNC storage as a result of higher N concentrations retained in leaves; however, this effect was species dependent and did not alter the growing and flowering phenology in the following seasons. Our results indicated that autumn warming increases carbohydrate accumulation, not only by enhancing activities of photosynthetic enzymes (a mechanism proposed in previous studies), but also by affecting chlorophyll degradation and preferential allocation of resources to different plant compartments. The different responses to warming can be explained by inherently different growth and phenology patterns observed among the studied species. The results implied that warming leads to changes in the competitive balance among life forms, an effect that can subsequently shift vegetation distribution and species composition in communities. C1 [Shi, Changguang; Sun, Geng; Zhang, Nannan; Wu, Ning] Chinese Acad Sci, Chengdu Inst Biol, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu, Peoples R China. [Shi, Changguang; Sun, Geng; Zhang, Nannan; Wu, Ning] Chinese Acad Sci, Chengdu Inst Biol, Ecol Restorat Biodivers Conservat Key Lab Sichuan, Chengdu, Peoples R China. [Shi, Changguang] Univ Chinese Acad Sci, Beijing, Peoples R China. [Zhang, Hongxuan; Xiao, Bingxue; Ze, Bai] Sichuan Acad Grassland Sci, Ctr Ecol Studies, Chengdu, Peoples R China. [Wu, Ning] Int Ctr Integrated Mt Dev ICIMOD, Ecosyst Serv, Kathmandu, Nepal. RP Sun, G (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Key Lab Mt Ecol Restorat & Bioresource Utilizat, Chengdu, Peoples R China. EM sungeng@cib.ac.cn; wuning@cib.ac.cn TC 47 Z9 53 PD SEP 18 PY 2014 VL 9 IS 9 AR e107874 DI 10.1371/journal.pone.0107874 UT WOS:000342921200057 DA 2023-03-23 ER PT J AU Cai, YJ Wang, XD Tian, LL Zhao, H Lu, XY Yan, Y AF Cai, Yanjiang Wang, Xiaodan Tian, Linlin Zhao, Hui Lu, Xuyang Yan, Yan TI The impact of excretal returns from yak and Tibetan sheep dung on nitrous oxide emissions in an alpine steppe on the Qinghai-Tibetan Plateau SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB This study describes the impact of excretal returns derived from livestock dung on nitrous oxide (N2O) emissions in a grazed alpine grassland ecosystem. N2O flux, vegetation and soil characteristics were measured in an alpine steppe on the Qinghai-Tibetan Plateau. Measurements were obtained from control (CK) plot and experimental plot to which either yak dung (YD) or Tibetan sheep dung (SD) was added. We found significantly lower surface soil temperature and higher soil moisture in the YD plot than in either the CK or SD plot. The application of YD resulted in significantly less biomass of aboveground vegetation, lower carbon and nitrogen uptake, and significantly higher cumulative N2O emission in comparison to the CK or SD treatment. N2O from SD treatment was probably mainly produced via nitrification, while N2O from YD treatment was primarily produced by denitrification. Emission factors of N2O for both YD and SD were far lower than the default values proposed by the IPCC and the release of N2O from YD and SD patches is low. (C) 2014 Elsevier Ltd. All rights reserved. C1 [Cai, Yanjiang; Wang, Xiaodan; Tian, Linlin; Zhao, Hui; Lu, Xuyang; Yan, Yan] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu, Peoples R China. RP Wang, XD (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, 9,Block 4,Renminnanlu Rd, Chengdu, Peoples R China. EM wxd@imde.ac.cn TC 35 Z9 45 PD SEP PY 2014 VL 76 BP 90 EP 99 DI 10.1016/j.soilbio.2014.05.008 UT WOS:000339695900011 DA 2023-03-23 ER PT J AU Li, XL Perry, GLW Brierley, G Sun, HQ Li, CH Lu, GX AF Li, X. -L. Perry, G. L. W. Brierley, G. Sun, H. -Q. Li, C. -H. Lu, G. -X. TI QUANTITATIVE ASSESSMENT OF DEGRADATION CLASSIFICATIONS FOR DEGRADED ALPINE MEADOWS (HEITUTAN), SANJIANGYUAN, WESTERN CHINA SO LAND DEGRADATION & DEVELOPMENT DT Article AB Improving our understanding of abiotic and biotic thresholds that are transgressed during ecosystem degradation is vital for effective landscape-level restoration. Establishing logical and consistent typologies of degradation is an important first-step in this process. Areas of degraded alpine meadow in western China are referred to as Heitutan (or black soil beach') and cover vast areas. Previously, four classes of grassland degradation have been differentiated in this large area: non-degraded alpine meadow and moderate, severe and extreme Heitutan. We evaluated existing field-based classifications of Heitutan in the Sanjiangyuan region, and examined the criteria on which these classifications are made, by using multivariate statistical approaches. First, we asked whether existing qualitative classifications, based on vegetation cover and the abundance of impalatable plant species, adequately describe the nature of degradation at different locations. We then used a suite of vegetation and soil measures collected across 175 sites spanning a range of degradation conditions to develop a new quantitative assessment of degradation across the alpine meadows of the Qinghai-Tibetan Plateau. Hierarchical classification highlights two broad classes of degradation: non-degraded alpine meadow and degraded Heitutan. The non-degraded category effectively combines the non-degraded grassland and moderate classes, whereas the degraded Heitutan combines the severe and extreme Heitutan classes. Ordination analyses suggest that the four previously recognized classes of degradation intergrade. Of the 14 biophysical variables used to classify subsites on the basis of their degradation, bare ground area and vegetation cover are the two most useful predictors of grassland condition and associated ecological threshold conditions. Copyright (c) 2012 John Wiley & Sons, Ltd. C1 [Li, X. -L.; Sun, H. -Q.; Li, C. -H.; Lu, G. -X.] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Li, X. -L.; Perry, G. L. W.; Brierley, G.] Univ Auckland, Sch Environm, Auckland 1, New Zealand. [Perry, G. L. W.] Univ Auckland, Sch Biol Sci, Auckland 1, New Zealand. RP Perry, GLW (通讯作者)，Univ Auckland, Sch Environm, Private Bag 92019, Auckland 1, New Zealand. EM george.perry@auckland.ac.nz TC 57 Z9 64 PD SEP-OCT PY 2014 VL 25 IS 5 BP 417 EP 427 DI 10.1002/ldr.2154 UT WOS:000342615900002 DA 2023-03-23 ER PT J AU Ma, Z Ma, MJ Baskin, JM Baskin, CC Li, JY Du, GZ AF Ma, Zhen Ma, Miaojun Baskin, Jerry M. Baskin, Carol C. Li, Junyong Du, Guozhen TI Responses of alpine meadow seed bank and vegetation to nine consecutive years of soil fertilization SO ECOLOGICAL ENGINEERING DT Article AB Decline in aboveground species diversity in response to nutrient enrichment has been demonstrated by many studies. However, information on the soil seed bank also is important for restoration of species-rich vegetation, but this subject has received little attention. The aim of this study was to investigate the relationship between the aboveground vegetation and the soil seed bank of an alpine meadow along a fertilization gradient that can germinate in spring. We determined species richness, density, life form and functional groups in the soil seed bank and in the aboveground vegetation along an N-P fertilization gradient from 0 to Fer(120) (120 g/m(2); i.e. 25.4 g N and 28.2 P m(2)/yr). Non-metric multidimensional scaling was used to test the similarity between soil seed bank and aboveground vegetation. Species richness of both soil seed bank and vegetation declined in response to 9 years of fertilization, but rate of decline in the seed bank was slower than that in the vegetation. Seed density did not differ along the fertilization gradient except for Fer(30), which had the highest seed density. Plant density in the vegetation declined along the fertilization gradient. Proportion of annuals increased both in the vegetation and the soil seed bank along a fertilization gradient. Percentage of different functional groups in the soil seed bank changed but less than that in the vegetation. The similarity between soil seed bank and vegetation increased from Fer(0) to Fer(90) and then decreased in Fern. Fertilization influenced species composition of the soil seed bank, but the effect was smaller than that on the aboveground vegetation. The seed bank present in spring provides high species richness and high seed densities for restoration, but restoration to the non-fertilized state would be difficult due to the shift to a higher proportion of annuals and to a low proportion of sedges along the fertilization gradient. (C) 2014 Elsevier B.V. All rights reserved. C1 [Ma, Zhen; Ma, Miaojun; Li, Junyong; Du, Guozhen] Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. [Baskin, Jerry M.; Baskin, Carol C.] Univ Kentucky, Dept Biol, Lexington, KY 40506 USA. [Baskin, Carol C.] Univ Kentucky, Dept Plant & Soil Sci, Lexington, KY 40506 USA. RP Ma, MJ (通讯作者)，Lanzhou Univ, Sch Life Sci, State Key Lab Grassland Agroecosyst, Lanzhou 730000, Gansu, Peoples R China. EM qinfenma@126.com; mamiaojun@gmail.com; ccbask0@uky.edu; jyli10@lzu.edu.cn; guozdu@lzu.edu.cn TC 24 Z9 28 PD SEP PY 2014 VL 70 BP 92 EP 101 DI 10.1016/j.ecoleng.2014.04.009 UT WOS:000340652100011 DA 2023-03-23 ER PT J AU Zhang, L Guo, HD Wang, CZ Ji, L Li, J Wang, K Dai, L AF Zhang, Li Guo, HuaDong Wang, CuiZhen Ji, Lei Li, Jing Wang, Kun Dai, Lin TI The long-term trends (1982-2006) in vegetation greenness of the alpine ecosystem in the Qinghai-Tibetan Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB The increased rate of annual temperature in the Qinghai-Tibetan Plateau exceeded all other areas of the same latitude in recent decades. The influence of the warming climate on the alpine ecosystem of the plateau was distinct. An analysis of alpine vegetation under changes in climatic conditions was conducted in this study. This was done through an examination of vegetation greenness and its relationship with climate variability using the Advanced Very High Resolution Radiometer satellite imagery and climate datasets. Vegetation in the plateau experienced a positive trend in greenness, with 18.0 % of the vegetated areas exhibiting significantly positive trends, which were primarily located in the eastern and southwestern parts of the plateau. In grasslands, 25.8 % of meadows and 14.1 % of steppes exhibited significant upward trends. In contrast, the broadleaf forests experienced a trend of degradation. Temperature, particularly summer temperature, was the primary factor promoting the vegetation growth in the plateau. The wetter and warmer climate in the east contributed to the favorable conditions for vegetation. The alpine meadow was mostly sensitive to temperature, while the steppes were sensitive to both temperature and precipitation. Although a warming climate was expected to be beneficial to vegetation growth in the alpine region, the rising temperature coupled with reduced precipitation in the south did not favor vegetation growth due to low humidity and poor soil moisture conditions. C1 [Zhang, Li; Guo, HuaDong; Wang, Kun; Dai, Lin] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Key Lab Digital Earth Sci, Beijing 100094, Peoples R China. [Zhang, Li; Li, Jing] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Wang, CuiZhen] Univ S Carolina, Dept Geog, Columbia, SC 29208 USA. [Ji, Lei] US Geol Survey, Earth Resources Observat & Sci EROS Ctr, ASRC InuTeq, Sioux Falls, SD 57198 USA. RP Zhang, L (通讯作者)，Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Key Lab Digital Earth Sci, Beijing 100094, Peoples R China. EM zhangli@radi.ac.cn TC 41 Z9 47 PD SEP PY 2014 VL 72 IS 6 BP 1827 EP 1841 DI 10.1007/s12665-014-3092-1 UT WOS:000341083800007 DA 2023-03-23 ER PT J AU Li, YY Dong, SK Liu, SL Wang, XX Wen, L Wu, Y AF Li, Yuan-Yuan Dong, Shi-Kui Liu, Shiliang Wang, Xuexia Wen, Lu Wu, Yu TI The interaction between poisonous plants and soil quality in response to grassland degradation in the alpine region of the Qinghai-Tibetan Plateau SO PLANT ECOLOGY DT Article AB The objective of this study was to explore the distribution of poisonous plants and soil quality in relation to grassland degradation in the Qinghai-Tibetan Plateau (QTP) by employing poisonous plants characteristics including diversity index, coverage and composition and the soil properties including soil physical, chemical, and biological indicators. The degraded grasslands (DGs) had significantly increased cover and diversity values of poisonous plants compared with the non-DGs (NDGs). Grassland use types had significant effects on the composition and characteristics of poisonous plants. The NDGs had increased levels of soil nutrients and soil enzyme activities, with decreased soil pH and bulk density (BD), indicating a higher and better soil nutrient status compared with DGs. The soil texture, soil pH, and soil BD were very important in affecting the structures of poisonous plants. We concluded that grassland degradation had significant effect on poisonous plants coverage and diversity; conversely, poisonous plants also aggregated the grassland degradation, decreasing the soil fertility in the QTP. C1 [Li, Yuan-Yuan; Dong, Shi-Kui; Liu, Shiliang; Wang, Xuexia; Wen, Lu; Wu, Yu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Dong, Shi-Kui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. RP Li, YY (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM yuanyuanhaha1989@163.com; dongshikui@sina.com TC 36 Z9 46 PD AUG PY 2014 VL 215 IS 8 BP 809 EP 819 DI 10.1007/s11258-014-0333-z UT WOS:000341091600002 DA 2023-03-23 ER PT J AU Luan, JW Cui, LJ Xiang, CH Wu, JH Song, HT Ma, QF AF Luan, Junwei Cui, Lijuan Xiang, Chenghua Wu, Jianghua Song, Hongtao Ma, Qiongfang TI Soil carbon stocks and quality across intact and degraded alpine wetlands in Zoige, east Qinghai-Tibet Plateau SO WETLANDS ECOLOGY AND MANAGEMENT DT Article AB The wetlands on the Qinghai-Tibet Plateau are experiencing serious degradation, with more than 90,000 hectares of marshland converted to wet meadow or meadow after 40 years of drainage. However, little is known about the effects of wetland conversion on soil C stocks and the quality of soil organic carbon (SOC) (defined by the proportion of labile versus more resistant organic carbon compounds). SOC, microbial biomass carbon, light fraction organic carbon (LFOC), dissolved organic carbon, and the chemical composition of SOC in the soil surface layer (0-10 cm), were investigated along a wetland degradation gradient (marsh, wet meadow, and meadow). Wetland degradation caused a 16 % reduction in the carbon stocks from marsh (178.7 +/- A 15.2 kg C m(-2)) to wet meadow (150.6 +/- A 21.5 kg C m(-2)), and a 32 % reduction in C stocks of the 0-10 cm soil layer from marsh to meadow (122.2 +/- A 2.6 kg C m(-2)). Wetland degradation also led to a significant reduction in SOC quality, represented by the lability of the carbon pool as determined by a density fractionation method (L (LFOC)), and a significant increase in the stability of the carbon pool as reflected by the alkyl-C:O-alkyl-C ratio. C-13 NMR spectroscopy showed that the labile form of C (O-alkyl-C) declined significantly after wetland degradation. These results assist in explaining the transformation of organic C in these plateau wetland soils and suggest that wetland degradation not only caused SOC loss, but also decreased the quality of the SOC of the surface soil. C1 [Luan, Junwei; Cui, Lijuan] Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China. [Luan, Junwei; Wu, Jianghua] Mem Univ Newfoundland, Corner Brook, NF A2H 6P9, Canada. [Xiang, Chenghua] Sichuan Acad Forestry, Chengdu 610081, Peoples R China. RP Luan, JW (通讯作者)，Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China. EM junweiluan@gmail.com; lkyclj@163.com TC 25 Z9 34 PD AUG PY 2014 VL 22 IS 4 BP 427 EP 438 DI 10.1007/s11273-014-9344-8 UT WOS:000339379400006 DA 2023-03-23 ER PT J AU Xiong, DP Shi, PL Sun, YL Wu, JS Zhang, XZ AF Xiong Dingpeng Shi Peili Sun Yinliang Wu Jianshuang Zhang Xianzhou TI Effects of grazing exclusion on plant productivity and soil carbon, nitrogen storage in alpine meadows in northern Tibet, China SO CHINESE GEOGRAPHICAL SCIENCE DT Article AB Grazing exclusion is widely adopted in restoring degraded alpine grasslands on the Qinghai-Tibetan Plateau. However, its effectiveness remains poorly understood. In this study, we investigated the effects of grazing exclusion on plant productivity, species diversity and soil organic carbon (SOC) and soil total nitrogen (STN) storage along a transect spanning from east to west of alpine meadows in northern Tibet, China. After six years of grazing exclusion, plant cover, aboveground biomass (AGB), belowground biomass (BGB), SOC and STN were increased, but species diversity indices declined. The enhancement of AGB and SOC caused by grazing exclusion was correlated positively with mean annual precipitation (MAP). Grazing exclusion led to remarkable biomass increase of sedge species, especially Kobresia pygmaea, whereas decrease of biomass in forbs and no obvious change in grass, leguminous and noxious species. Root biomass was concentrated in the near surface layer (10 cm) after grazing exclusion. The effects of grazing exclusion on SOC storage were confined to shallow soil layer in sites with lower MAP. It is indicated that grazing exclusion is an effective measure to increase forage production and enhance soil carbon sequestration in the studied region. The effect is more efficient in sites with higher precipitation. However, the results revealed a tradeoff between vegetation restoration and ecological biodiversity. Therefore, carbon pools recover more quickly than plant biodiversity in the alpine meadows. We suggest that grazing exclusion should be combined with other measures to reconcile grassland restoration and biodiversity conservation. C1 [Xiong Dingpeng; Shi Peili; Sun Yinliang; Wu Jianshuang; Zhang Xianzhou] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Natl Ecol Res Stn, Beijing 100101, Peoples R China. [Xiong Dingpeng; Sun Yinliang] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Natl Ecol Res Stn, Beijing 100101, Peoples R China. EM shipl@igsnrr.ac.cn TC 56 Z9 71 PD AUG PY 2014 VL 24 IS 4 BP 488 EP 498 DI 10.1007/s11769-014-0697-y UT WOS:000339332100012 DA 2023-03-23 ER PT J AU Cai, XB Peng, YL Yang, MN Zhang, T Zhang, Q AF Cai, Xiao-Bu Peng, Yue-Lin Yang, Min-Na Zhang, Tao Zhang, Qiang TI Grassland Degradation Decrease the Diversity of Arbuscular Mycorrhizal Fungi Species in Tibet Plateau SO NOTULAE BOTANICAE HORTI AGROBOTANICI CLUJ-NAPOCA DT Article AB Arbuscular mycorrhizal (AM) fungi play a vital role in restoration of an ecosystem. Grassland degradation in alpine steppe is severe, but the influence of grassland degradation on AM fungi composition in Tibetan Plateau is still not well understood. This research studied the diversity of arbuscular mycorrhizal fungi in degraded alpine steppe, dominated by Stipa purpurea. The results showed that the species richness and abundance of AM fungi in degraded grasslands significantly decreased. In different typical grasslands species, diversity of AM fungi genus Glomus was much higher than other genera (Acaulospora and Scutellospora). Compared with normal grassland, the AM fungal species diversity in moderately degraded grassland decreased by 30%, but in lightly degraded and severely degraded grassland, it highly increased with 15.3% and 13.3%, respectively. The species diversity of genus Glomus in moderately degraded grassland and lightly degraded grassland were higher than for normal grassland. Significant differences were observed in a relative abundance of common dominant species among different degraded grasslands. The proportion of dominant species highly increased with the aggravation of grassland degradation. The results suggest that the grassland mild degradation increased the adaptability and stress resistance of species. C1 [Cai, Xiao-Bu] Tibet Agr & Anim Husb Coll, Dept Resources & Environm, Linzhi 860000, Tibet, Peoples R China. [Peng, Yue-Lin; Yang, Min-Na] Tibet Agr & Anim Husb Coll, Dept Plant Sci, Linzhi 860000, Tibet, Peoples R China. [Zhang, Tao] NE Normal Univ, Inst Grassland Sci, Minist Educ, Key Lab Vegetat Ecol, Changchun 130024, Peoples R China. [Zhang, Qiang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. RP Zhang, T (通讯作者)，NE Normal Univ, Inst Grassland Sci, Minist Educ, Key Lab Vegetat Ecol, Changchun 130024, Peoples R China. EM zhangt946@nenu.edu.cn; zhangqiang_zz@163.com TC 12 Z9 17 PD JUL-DEC PY 2014 VL 42 IS 2 BP 333 EP 339 DI 10.15835/nbha4229458 UT WOS:000346326700005 DA 2023-03-23 ER PT J AU Yi, SH Wang, XY Qin, Y Xiang, B Ding, YJ AF Yi, Shuhua Wang, Xiaoyun Qin, Yu Xiang, Bo Ding, Yongjian TI Responses of alpine grassland on Qinghai-Tibetan plateau to climate warming and permafrost degradation: a modeling perspective SO ENVIRONMENTAL RESEARCH LETTERS DT Article AB Permafrost plays a critical role in soil hydrology. Thus, the degradation of permafrost under warming climate conditions may affect the alpine grassland ecosystem on the Qinghai-Tibetan Plateau. Previous space-for-time studies using plot and basin scales have reached contradictory conclusions. In this study, we applied a process-based ecosystem model (DOS-TEM) with a state-of-the-art permafrost hydrology scheme to examine this issue. Our results showed that 1) the DOS-TEM model could properly simulate the responses of soil thermal and hydrological dynamics and of ecosystem dynamics to climate warming and spatial differences in precipitation; 2) the simulated results were consistent with plot-scale studies showing that warming caused an increase in maximum unfrozen thickness, a reduction in vegetation and soil carbon pools as a whole, and decreases in soil water content, net primary production, and heterotrophic respiration; and 3) the simulated results were also consistent with basin-scale studies showing that the ecosystem responses to warming were different in regions with different combinations of water and energy constraints. Permafrost prevents water from draining into water reservoirs. However, the degradation of permafrost in response to warming is a long-term process that also enhances evapotranspiration. Thus, the degradation of the alpine grassland ecosystem on the Qinghai-Tibetan Plateau (releasing carbon) cannot be mainly attributed to the disappearing waterproofing function of permafrost. C1 [Yi, Shuhua; Wang, Xiaoyun; Qin, Yu; Ding, Yongjian] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China. [Wang, Xiaoyun] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Xiang, Bo] Chongqing Meteorol Adm, Chongqing 404100, Peoples R China. RP Yi, SH (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, 320 Donggang West Rd, Lanzhou 730000, Peoples R China. EM yis@lzb.ac.cn TC 57 Z9 63 PD JUL PY 2014 VL 9 IS 7 AR 074014 DI 10.1088/1748-9326/9/7/074014 UT WOS:000341873200015 DA 2023-03-23 ER PT J AU Gao, JG Zhang, YL Liu, LS Wang, ZF AF Gao, Jun-Gang Zhang, Yi-Li Liu, Lin-Shan Wang, Zhao-Feng TI Climate change as the major driver of alpine grasslands expansion and contraction: A case study in the Mt. Qomolangma (Everest) National Nature Preserve, southern Tibetan Plateau SO QUATERNARY INTERNATIONAL DT Article AB To assess the spatial patterns of alpine grassland changes (expansion and contraction) and their responses to climate changes in the context of global change in recent years on the southern Tibetan Plateau, the Mt. Qomomagma National Nature Preserve (QNNP), covering an area of 36 594 km(2) and located on the southern Tibetan Plateau was selected as the study area. Alpine grassland cover was obtained by image reclassification of more than five pairs of remote sensing images taken in 1976-2006. Expansion and contraction were determined by cover changes in alpine grassland and expressed as binary variables. Logistic regression was then used to analyze the impacts of climatic-, neighborhood-, and topographic-related variables on alpine grassland changes. In the study period, the area of alpine grassland increased by 84.3 km(2). The expansion rate is significantly higher on the gentle slopes with higher mean annual temperature (MAT), interannual variability trend of temperature (IVT), and inter-annual variability trend of precipitation (IVP), and also in areas close to lakes and distant from roads. While most contraction is found on the gentle slopes and in areas close to streams, lakes, and roads; the MAT is also a significant driven impact factor. Alpine grassland expansion and contraction in the QNNP were significantly affected by MAT but not by mean annual precipitation (MAP). The IVT and IVP had significant effects on alpine grassland expansion but not on contraction. The results contradict the prevailing view that climate changes, such as increased temperature with decreased precipitation, would exacerbate grassland degradation on the Tibetan Plateau. This study indicated that climate changes have different effects on alpine grassland changes in different areas of the Tibetan Plateau. (C) 2013 Elsevier Ltd and INQUA. All rights reserved. C1 [Gao, Jun-Gang; Zhang, Yi-Li; Liu, Lin-Shan; Wang, Zhao-Feng] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. RP Zhang, YL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. EM jungang.gao@163.com; zhangyl@igsnrr.ac.cn TC 33 Z9 36 PD JUN 26 PY 2014 VL 336 BP 108 EP 116 DI 10.1016/j.quaint.2013.09.035 UT WOS:000338402600014 DA 2023-03-23 ER PT J AU Li, X Yang, YQ Ma, L Sun, XD Yang, SH Kong, XX Hu, XY Yang, YP AF Li, Xiong Yang, Yunqiang Ma, Lan Sun, Xudong Yang, Shihai Kong, Xiangxiang Hu, Xiangyang Yang, Yongping TI Comparative Proteomics Analyses of Kobresia pygmaea Adaptation to Environment along an Elevational Gradient on the Central Tibetan Plateau SO PLOS ONE DT Article AB Variations in elevation limit the growth and distribution of alpine plants because multiple environmental stresses impact plant growth, including sharp temperature shifts, strong ultraviolet radiation exposure, low oxygen content, etc. Alpine plants have developed special strategies to help survive the harsh environments of high mountains, but the internal mechanisms remain undefined. Kobresia pygmaea, the dominant species of alpine meadows, is widely distributed in the Southeastern Tibet Plateau, Tibet Autonomous Region, China. In this study, we mainly used comparative proteomics analyses to investigate the dynamic protein patterns for K. pygmaea located at four different elevations (4600, 4800, 4950 and 5100 m). A total of 58 differentially expressed proteins were successfully detected and functionally characterized. The proteins were divided into various functional categories, including material and energy metabolism, protein synthesis and degradation, redox process, defense response, photosynthesis, and protein kinase. Our study confirmed that increasing levels of antioxidant and heat shock proteins and the accumulation of primary metabolites, such as proline and abscisic acid, conferred K. pygmaea with tolerance to the alpine environment. In addition, the various methods K. pygmaea used to regulate material and energy metabolism played important roles in the development of tolerance to environmental stress. Our results also showed that the way in which K. pygmaea mediated stomatal characteristics and photosynthetic pigments constitutes an enhanced adaptation to alpine environmental stress. According to these findings, we concluded that K. pygmaea adapted to the high-elevation environment on the Tibetan Plateau by aggressively accumulating abiotic stress-related metabolites and proteins and by the various life events mediated by proteins. Based on the species'lexible physiological and biochemical processes, we surmised that environment change has only a slight impact on K. pygmaea except for possible impacts to populations on vulnerable edges of the species' range. C1 [Li, Xiong; Yang, Yunqiang; Ma, Lan; Sun, Xudong; Kong, Xiangxiang; Hu, Xiangyang; Yang, Yongping] Chinese Acad Sci, Kunming Inst Bot, Key Lab Plant Biodivers & Biogeog East Asia, Kunming, Peoples R China. [Li, Xiong; Yang, Yunqiang; Ma, Lan; Sun, Xudong; Kong, Xiangxiang; Hu, Xiangyang; Yang, Yongping] Chinese Acad Sci, Plant Germplasm & Genom Ctr, Germplasm Bank Wild Species, Kunming Inst Bot, Kunming, Peoples R China. [Li, Xiong; Yang, Yunqiang; Ma, Lan; Yang, Shihai; Kong, Xiangxiang] Univ Chinese Acad Sci, Beijing, Peoples R China. [Yang, Shihai] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing, Peoples R China. RP Hu, XY (通讯作者)，Chinese Acad Sci, Kunming Inst Bot, Key Lab Plant Biodivers & Biogeog East Asia, Kunming, Peoples R China. EM huxiangyang@mail.kib.ac.cn; yangyp@mail.kib.ac.cn TC 24 Z9 26 PD JUN 2 PY 2014 VL 9 IS 6 AR e98410 DI 10.1371/journal.pone.0098410 UT WOS:000336956300063 DA 2023-03-23 ER PT J AU Chen, BX Zhang, XZ Tao, J Wu, JS Wang, JS Shi, PL Zhang, YJ Yu, CQ AF Chen, Baoxiong Zhang, Xianzhou Tao, Jian Wu, Jianshuang Wang, Jingsheng Shi, Peili Zhang, Yangjian Yu, Chengqun TI The impact of climate change and anthropogenic activities on alpine grassland over the Qinghai-Tibet Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Climate change and anthropogenic activities are two factors that have important effects on the carbon cycle of terrestrial ecosystems, but it is almost impossible to fully separate them at present. This study used process-based terrestrial ecosystem model to stimulate the potential climate-driven alpine grassland net primary production (NPP), and Carnegie-Ames-Stanford Approach based on remote sensing to stimulate actual alpine grassland NPP influenced by both of climate change and anthropogenic activities over the Qinghai-Tibet plateau (QTP) from 1982 to 2011. After the models were systematically calibrated, the simulations were validated with continuous 3-year paired field sample data, which were separately collected in fenced and open grasslands. We then simulated the human-induced NPP, calculated as the difference between potential and actual NPP, to determine the effect of anthropogenic activities on the alpine grassland ecosystem. The simulation results showed that the climate change and anthropogenic activities mainly drove the actual grassland NPP increasing in the first 20-year and the last 10-year respectively, the area percentage of actual grassland NPP change caused by climate change declined from 79.62% in the period of 1982-2001 to 56.59% over the last 10 years; but the percentage change resulting from human activities doubled from 20.16% to 42.98% in the same periods over the QTP. The effect of human activities on the alpine grassland ecosystem obviously intensified in the latter period compared with the former 20 years, so the negative effect caused by climate change to ecosystem could have been relatively mitigated or offset over the QTP in the last ten years. (C) 2014 Elsevier B.V. All rights reserved. C1 [Chen, Baoxiong; Zhang, Xianzhou; Tao, Jian; Wu, Jianshuang; Wang, Jingsheng; Shi, Peili; Zhang, Yangjian; Yu, Chengqun] Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Chen, Baoxiong] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. RP Zhang, XZ (通讯作者)，Chinese Acad Sci, Lhasa Plateau Ecosyst Res Stn, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM zhangxz@igsnrr.ac.cn TC 386 Z9 477 PD JUN 1 PY 2014 VL 189 BP 11 EP 18 DI 10.1016/j.agrformet.2014.01.002 UT WOS:000333852900003 DA 2023-03-23 ER PT J AU Shen, MG Zhang, GX Cong, N Wang, SP Kong, WD Piao, SL AF Shen, Miaogen Zhang, Gengxin Cong, Nan Wang, Shiping Kong, Weidong Piao, Shilong TI Increasing altitudinal gradient of spring vegetation phenology during the last decade on the Qinghai-Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Spring vegetation phenology in temperate and cold regions is widely expected to advance with increasing temperature, and is often used to indicate regional climatic change. The Qinghai-Tibetan Plateau (QTP) has recently experienced intensive warming, but strongly contradictory evidence exists regarding changes in satellite retrievals of spring vegetation phenology. We investigated spatio-temporal variations in green-up date on the QTP from 2000 to 2011, as determined by five methods employing vegetation indices from each of the four sources: three Normalized Difference Vegetation Index (NDVI) from the Advanced Very High Resolution Radiometer (AVHRR), Systeme Pour l'Observation de la Terre (SPOT), MODerate resolution Imaging Spectroradiometer (MODIS), and the Enhanced Vegetation Index (EVI) from MODIS. Results indicate that, at the regional scale, all vegetation indices and processing methods consistently found no significant temporal trend (all P > 0.05). This insignificance resulted from substantial spatial heterogeneity of trends in green-up date, with a notably delay in the southwest region, and widespread advancing trend in the other areas, despite a region-wide temperature increase. These changes doubled the altitudinal gradient of green-up date, from 0.63 days 100 m(-1) in the early 2000s to 1.30 days 100 m(-1) in the early 2010s. The delays in the southwest region and at high altitudes were likely caused by the decline in spring precipitation, rather than the increasing spring temperature, suggesting that spring precipitation may be an important regulator of spring phenological response to climatic warming over a considerable area of the QTP. Consequently, a delay in spring vegetation phenology in the QTP may not necessarily indicate spring cooling. Furthermore, the phenological changes retrieved from the widely used AVHRR NDVI differed from those retrieved from SPOT and MODIS NDVIs and MODIS EVI, necessitating the use of multiple datasets when monitoring vegetation dynamics from space. (C) 2014 Elsevier B.V. All rights reserved. C1 [Shen, Miaogen; Zhang, Gengxin; Wang, Shiping; Kong, Weidong; Piao, Shilong] Chinese Acad Sci, Lab Alpine Ecol & Biodivers, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. [Cong, Nan] Peking Univ, Dept Ecol, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. RP Zhang, GX (通讯作者)，Chinese Acad Sci, Lab Alpine Ecol & Biodivers, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. EM zhangg@itpcas.ac.cn TC 276 Z9 314 PD JUN 1 PY 2014 VL 189 BP 71 EP 80 DI 10.1016/j.agrformet.2014.01.003 UT WOS:000333852900009 DA 2023-03-23 ER PT J AU Liu, B Shen, WS Lin, NF Li, R Yue, YM AF Liu, Bo Shen, Weishou Lin, Naifeng Li, Ru Yue, Yuemin TI Deriving vegetation fraction information for the alpine grassland on the Tibetan plateau using in situ spectral data SO JOURNAL OF APPLIED REMOTE SENSING DT Article AB Vegetation fraction (VF) is the indispensable factor involved in the assessment of land degradation in the inclement climate condition and harsh natural environment. Based on the analysis of an in situ spectral dataset of alpine grasslands on the Tibetan plateau, we assessed the performance of 28 widely used vegetation indices (VIs) and a spectral mixture analysis (SMA) model applied on the analytical spectral device and simulated enhanced thematic mapper (ETM)+ and Huan Jing (HJ)-1 data to select a method for retrieving VF there. The results show that simple VIs are competent for extracting VF information, and VIs with an extra blue band involved will produce a better performance. However, involvement of too many more bands does not yield much higher accuracy, indicated by the fact that hyperspectral VIs are not superior to multispectral ones in our case. The SMA model provides an acceptable accuracy as well but lower than that of VI regression. In addition, the normalized difference vegetation index (NDVI) values of vegetation and soil, generally, as the key parameter in the widely used NDVI-SMA model is obtained, and this would benefit the application of this model to derive VF of alpine grasslands on the Tibetan plateau with minimal or no need for field work support. (C) 2014 Society of Photo-Optical Instrumentation Engineers (SPIE) C1 [Liu, Bo; Shen, Weishou; Lin, Naifeng] Nanjing Inst Environm Sci, Minist Environm Protect, Nanjing 210042, Jiangsu, Peoples R China. [Li, Ru] Chinese Acad Sci, Inst Remote Sensing & Digital Earth, Beijing 100101, Peoples R China. [Yue, Yuemin] Chinese Acad Sci, Inst Subtrop Agr, Changsha 410125, Hunan, Peoples R China. RP Shen, WS (通讯作者)，Nanjing Inst Environm Sci, Minist Environm Protect, Nanjing 210042, Jiangsu, Peoples R China. EM shenweishou@163.com TC 10 Z9 10 PD MAY 13 PY 2014 VL 8 AR 083630 DI 10.1117/1.JRS.8.083630 UT WOS:000336783900001 DA 2023-03-23 ER PT J AU Blankinship, JC Hart, SC AF Blankinship, Joseph C. Hart, Stephen C. TI Hydrological Control of Greenhouse Gas Fluxes in a Sierra Nevada Subalpine Meadow SO ARCTIC ANTARCTIC AND ALPINE RESEARCH DT Article AB Alpine and subalpine meadows are often hotspots of water availability and biodiversity in montane landscapes, but we know little about whether these attributes also make meadows hotspots of greenhouse gas (GHG) emission. Furthermore, many of these meadows will likely become drier during the growing season in the future because of less precipitation, earlier timing of snowmelt, and increased evapotranspiration associated with climatic warming. To evaluate the potential effects of soil drying on GHG emission, we studied a soil moisture gradient in a Sierra Nevada subalpine meadow in California. Our objectives were: (1) to assess the strength of hydrological control for soil carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes both earlier and later in the growing season; and (2) to quantify the contribution of CH4 and N2O to net GHG emission. The replicated gradient spanned 50 m, from the wet middle to dry edge of the meadow, and soil volumetric water content was measured 0 to 12 cm deep. Fluxes of CO2, CH4, and N2O were measured using static chambers at 10 m intervals across the gradient. We found that the wet side of the gradient was not a CH4 or N2O source on either sampling date. Net CH4 emission from soil was rare and CH4 uptake was prevalent, particularly on the dry side of the gradient. Soil N2O fluxes shifted from net uptake at the middle of the meadow to net emission at the edge, but only earlier in the growing season. Of the three GHGs, CO2 fluxes showed the most temporal variation but surprisingly varied little across the hydrological gradient. Other environmental factors-including plant species richness and soil carbon concentration-appeared more important than soil moisture in explaining CO2 fluxes. Therefore, the strength of near-surface hydrological control increased in the following order: CO2 < N2O < CH4. Our results suggest that non-CO2 greenhouse gases will need proper accounting during the snow-free season in order to more accurately predict the effects of future soil drying on GHG emissions in heterogeneous montane landscapes. C1 [Blankinship, Joseph C.; Hart, Stephen C.] Univ Calif Merced, Merced, CA 95343 USA. [Blankinship, Joseph C.; Hart, Stephen C.] Univ Calif Merced, Sierra Nevada Res Inst, Merced, CA 95343 USA. RP Blankinship, JC (通讯作者)，Univ Calif Santa Barbara, Earth Res Inst, Santa Barbara, CA 93108 USA. EM joseph.blankinship@lifesci.ucsb.edu TC 5 Z9 5 PD MAY PY 2014 VL 46 IS 2 BP 355 EP 364 DI 10.1657/1938-4246-46.2.355 UT WOS:000336778500006 DA 2023-03-23 ER PT J AU Tian, XF Hu, HW Ding, Q Song, MH Xu, XL Zheng, Y Guo, LD AF Tian, Xiao-Fang Hu, Hang-Wei Ding, Qiong Song, Ming-Hua Xu, Xing-Liang Zheng, Yong Guo, Liang-Dong TI Influence of nitrogen fertilization on soil ammonia oxidizer and denitrifier abundance, microbial biomass, and enzyme activities in an alpine meadow SO BIOLOGY AND FERTILITY OF SOILS DT Article AB Terrestrial ecosystems are predicted to experience an increasing level of atmospheric nitrogen (N) deposition, which may cause significant shifts in plant community composition and concomitantly stimulate soil acidification. However, little is known concerning the effects of N deposition on belowground microbial communities in alpine grassland ecosystems such as on the Tibetan Plateau. This study examined the responses of soil N-transforming microbes (measured after DNA extraction and quantitative PCR), soil microbial biomass C (SMBC) and N (SMBN), and soil enzyme activities to different forms (NH4 (+)-N, NO3 (-)-N, and NH4NO3-N) and rates (1.5 and 7.5 g N m(-2) year(-1), denoted as low and high N, respectively) of N fertilization (addition) in two successive plant growing seasons. The N rate, not N form, influenced the abundance of ammonia-oxidizing archaea (AOA). High N addition significantly increased ammonia-oxidizing bacteria (AOB) abundance which differed across different N form treatments. Nitrogen addition had no significant impact on the abundance of soil denitrifiers. The SMBC and SMBN were significantly decreased by high N additions, but no difference was found among different N forms. Despite higher urease activities being detected in the late plant growing season, the activities of invertase and alkaline phosphomonoesterase stayed unchanged irrespective of the different N amendments and plant growing season. Significant positive correlations were found between potential nitrification rates and AOB abundances. These results highlight that AOB seemed to respond more sensitively to different N fertilization and might have prominent roles in soil N cycling processes in this Tibetan Plateau alpine meadow than AOA. C1 [Tian, Xiao-Fang; Ding, Qiong; Zheng, Yong; Guo, Liang-Dong] Chinese Acad Sci, Inst Microbiol, State Key Lab Mycol, Beijing 100101, Peoples R China. [Hu, Hang-Wei; Zheng, Yong] Univ Western Sydney, Hawkesbury Inst Environm, Penrith, NSW 2751, Australia. [Song, Ming-Hua; Xu, Xing-Liang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. RP Zheng, Y (通讯作者)，Chinese Acad Sci, Inst Microbiol, State Key Lab Mycol, Beijing 100101, Peoples R China. EM zhengy@im.ac.cn TC 65 Z9 79 PD MAY PY 2014 VL 50 IS 4 BP 703 EP 713 DI 10.1007/s00374-013-0889-0 UT WOS:000334935000015 DA 2023-03-23 ER PT J AU Lehnert, LW Meyer, H Meyer, N Reudenbach, C Bendix, J AF Lehnert, Lukas W. Meyer, Hanna Meyer, Nele Reudenbach, Christoph Bendix, Joerg TI A hyperspectral indicator system for rangeland degradation on the Tibetan Plateau: A case study towards spaceborne monitoring SO ECOLOGICAL INDICATORS DT Article AB The Tibetan Plateau suffers from progressive degradation caused by over-grazing due to improper livestock management, global climate change and herbivory from small mammals. Therefore, a robust indicator system for rangeland degradation has to be developed and tested. This paper investigates local patterns of degradation at two sites (Lake Namco and Mt. Kailash) in Xizang province (China) that are covered by vegetation types typical of a large portion of the plateau. The suitability of a two-indicator system is analysed using hyperspectral field measurements, and its transferability to spaceborne data is tested. The indicators are (1) land-cover fractions derived from linear spectral unmixing and (2) chlorophyll content as a proxy for nutrient and water availability calculated using hyperspectral vegetation indices and partial least squares regression. Because cattle remain near settlements overnight in the local semi-nomadic pastoral system, it can be expected that grazing intensity is highest near the settlement and declines with increasing distance. Therefore, we tested the effect of distance on both indicators using a Spearman correlation analysis. The predicted chlorophyll content and land cover fractions of the indicator system were in good agreement with field observations (correlation coefficients between 0.70 and 0.98). High correlations between distance from settlements and land-cover fractions at both study sites demonstrated that the land-cover fraction is a reliable indicator for degradation. A positive correlation between distance from settlements and photosynthetically active vegetation (PV) revealed over-grazing patterns at the first site. Furthermore, the chlorophyll indicator was proven suitable because chlorophyll concentration declined with increasing distance from settlements. This underlines the over-grazing pattern because cattle excrement was the only external source of nutrients in the ecosystem and it was positively correlated with grazing intensity. However, at the second site, we found a significant positive effect of distance on the amount of photosynthetically non-active vegetation; no effect of distance on PV and chlorophyll content was found. Therefore, no evidence of pasture degradation was detected at the second site. Regarding the potential use of satellite data for degradation monitoring, we found that (1) the land-cover indicator derived from multispectral data was more robust than using noise-filtered hyperspectral information and (2) the chlorophyll amount indicator was estimated from simulated EnMAP data with low error rates. Because the proposed two-indicator system can be derived from multi- and hyperspectral satellite data and combines site conditions and local plant cover, it provides a time-saving and robust method to measure pasture degradation across large areas, assuming that respective satellite data are available. (C) 2013 Published by Elsevier Ltd. C1 [Lehnert, Lukas W.; Meyer, Hanna; Reudenbach, Christoph; Bendix, Joerg] Univ Marburg, Dept Geog, D-35037 Marburg, Germany. [Meyer, Nele] Univ Bonn, Dept Geog, D-53115 Bonn, Germany. RP Lehnert, LW (通讯作者)，Univ Marburg, Dept Geog, Deutschhausstr 10, D-35037 Marburg, Germany. EM lukas.lehnert@staff.uni-marburg.de; hanna.meyer@geo.uni-marburg.de; nele.meyer@uni-bonn.de; reudenbach@geo.uni-marburg.de; bendix@staff.uni-marburg.de TC 46 Z9 55 PD APR PY 2014 VL 39 BP 54 EP 64 DI 10.1016/j.ecolind.2013.12.005 UT WOS:000331685600006 DA 2023-03-23 ER PT J AU Zhang, W Liu, CY Zheng, XH Fu, YF Hu, XX Cao, GM Butterbach-Bahl, K AF Zhang, Wei Liu, Chunyan Zheng, Xunhua Fu, Yongfeng Hu, Xiaoxia Cao, Guangmin Butterbach-Bahl, Klaus TI The increasing distribution area of zokor mounds weaken greenhouse gas uptakes by alpine meadows in the Qinghai-Tibetan Plateau SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB The population of the plateau zokor (Myospalax fontanierii) rapidly increases on the degraded alpine meadows of Qinghai-Tibetan Plateau. The burrowing and feeding activities of plateau zokor exert huge effects on the plant community and soil properties. However, the possible effects on the production and consumption of greenhouse gases have not been investigated. To evaluate the effects, we measured the ecosystem respiration (Re), soil methane (CH4) and nitrous oxide (N2O) fluxes and the main soil, vegetation and environmental factors of zokor mounds of different excavation years (one-, two- and three to five-year, hereafter referred to as ZM1, ZM2 and ZM3-5) and surrounding control meadow (CM) in a typical Kobresia humilis meadow from July to November 2012. The cumulative Re, CH4 uptake and N2O emissions were 1.82 +/- 0.28, 2.83 +/- 0.48, 3.13 +/- 0.13 and 3.91 +/- 0.27 ton C ha(-1), 1.55 +/- 0.27, 1.33 +/- 0.15, 1.20 +/- 0.16 and 1.02 +/- 0.25 kg C ha(-1) and 0.23 +/- 0.02, 0.10 +/- 0.04, 0.08 +/- 0.01 and 0.07 +/- 0.02 kg N ha(-1) for ZM1, ZM2, ZM3-5 and CM, respectively. The soil CH4 uptake and N2O emission were stimulated and the Re was inhibited for ZM1, ZM2 and ZM3-5 as compared to the CM. If the distribution area of zokor mounds increased from 2% to 6%, the combined CO2-equivalent of CH4 and N2O exchanges strengthened 3.2 times. Furthermore, the composition of plant community altered; the plant biomass, topsoil organic carbon content, temperature and moisture decreased; and the topsoil gas permeability, inorganic nitrogen and dissolved organic carbon contents increased on zokor mounds as compared to the CM (P < 0.05). The recovery process of the vegetation and soil organic carbon pools of zokor mounds requires many years (>10 years). In view of the loss of soil organic carbon and the stimulation of N2O emission, the increasing distribution area of zokor mounds weaken the function of alpine meadows on the Qinghai-Tibetan Plateau as a greenhouse gas sink. (C) 2014 Elsevier Ltd. All rights reserved. C1 [Zhang, Wei; Liu, Chunyan; Zheng, Xunhua; Fu, Yongfeng; Hu, Xiaoxia] Chinese Acad Sci, State Key Lab Atmospher Boundary Layer Phys & Atm, Inst Atmospher Phys, Beijing 100029, Peoples R China. [Cao, Guangmin] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810001, Qinghai, Peoples R China. [Butterbach-Bahl, Klaus] Karlsruhe Res Ctr, Inst Meteorol & Climate Res, Atmospher Environm Res IMK IFU, D-82467 Garmisch Partenkirchen, Germany. RP Liu, CY (通讯作者)，Chinese Acad Sci, State Key Lab Atmospher Boundary Layer Phys & Atm, Inst Atmospher Phys, Beijing 100029, Peoples R China. EM lcy@post.iap.ac.cn TC 41 Z9 47 PD APR PY 2014 VL 71 BP 105 EP 112 DI 10.1016/j.soilbio.2014.01.005 UT WOS:000333508400012 DA 2023-03-23 ER PT J AU Zhang, YL Qi, W Zhou, CP Ding, MJ Liu, LS Gao, JG Bai, WQ Wang, ZF Zheng, D AF Zhang Yili Qi Wei Zhou Caiping Ding Mingjun Liu Linshan Gao Jungang Bai Wanqi Wang Zhaofeng Zheng Du TI Spatial and temporal variability in the net primary production of alpine grassland on the Tibetan Plateau since 1982 SO JOURNAL OF GEOGRAPHICAL SCIENCES DT Article AB Based on the GIMMS AVHRR NDVI data (8 km spatial resolution) for 1982-2000, the SPOT VEGETATION NDVI data (1 km spatial resolution) for 1998-2009, and observational plant biomass data, the CASA model was used to model changes in alpine grassland net primary production (NPP) on the Tibetan Plateau (TP). This study will help to evaluate the health conditions of the alpine grassland ecosystem, and is of great importance to the promotion of sustainable development of plateau pasture and to the understanding of the function of the national ecological security shelter on the TP. The spatio-temporal characteristics of NPP change were investigated using spatial statistical analysis, separately on the basis of physico-geographical factors (natural zone, altitude, latitude and longitude), river basin, and county-level administrative area. Data processing was carried out using an ENVI 4.8 platform, while an ArcGIS 9.3 and ANUSPLIN platform was used to conduct the spatial analysis and mapping. The primary results are as follows: (1) The NPP of alpine grassland on the TP gradually decreases from the southeast to the northwest, which corresponds to gradients in precipitation and temperature. From 1982 to 2009, the average annual total NPP in the TP alpine grassland was 177.2x10(12) gC yr(-1)(yr represents year), while the average annual NPP was 120.8 gC m(-2) yr(-1). (2) The annual NPP in alpine grassland on the TP fluctuates from year to year but shows an overall positive trend ranging from 114.7 gC m(-2) yr(-1) in 1982 to 129.9 gC m(-2) yr(-1) in 2009, with an overall increase of 13.3%; 32.56% of the total alpine grassland on the TP showed a significant increase in NPP, while only 5.55% showed a significant decrease over this 28-year period. (3) Spatio-temporal characteristics are an important control on annual NPP in alpine grassland: a) NPP increased in most of the natural zones on the TP, only showing a slight decrease in the Ngari montane desert-steppe and desert zone. The positive trend in NPP in the high-cold shrub-meadow zone, high-cold meadow steppe zone and high-cold steppe zone is more significant than that of the high-cold desert zone; b) with increasing altitude, the percentage area with a positive trend in annual NPP follows a trend of "increasing-stable-decreasing", while the percentage area with a negative trend in annual NPP follows a trend of "decreasing-stable-increasing", with increasing altitude; c) the variation in annual NPP with latitude and longitude co-varies with the vegetation distribution; d) the variation in annual NPP within the major river basins has a generally positive trend, of which the growth in NPP in the Yellow River Basin is most significant. Results show that, based on changes in NPP trends, vegetation coverage and phonological phenomenon with time, NPP has been declining in certain places successively, while the overall health of the alpine grassland on the TP is improving. C1 [Zhang Yili; Qi Wei; Zhou Caiping; Ding Mingjun; Liu Linshan; Gao Jungang; Bai Wanqi; Wang Zhaofeng; Zheng Du] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Qi Wei] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Ding Mingjun] Jiangxi Normal Univ, Nanchang 330028, Peoples R China. RP Zhang, YL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM zhangyl@igsnrr.ac.cn; firefoxqiwei@qq.com TC 105 Z9 131 PD APR PY 2014 VL 24 IS 2 BP 269 EP 287 DI 10.1007/s11442-014-1087-1 UT WOS:000329619000006 DA 2023-03-23 ER PT J AU Zhong, X Peng, QY Li, SS Chen, H Sun, HX Zhang, GR Liu, X AF Zhong, Xin Peng, Qing-yun Li, Shao-Song Chen, Hai Sun, Hong-Xia Zhang, Gu-Ren Liu, Xin TI Detection of Ophiocordyceps sinensis in the roots of plants in alpine meadows by nested-touchdown polymerase chain reaction SO FUNGAL BIOLOGY DT Article AB Ophiocordyceps sinensis, one of the most important income sources of rural Tibetan families, is an entomopathogenic fungus that parasitizes the ghost moth Thitarodes larvae, which live in alpine meadows on the Tibetan Plateau and in the Himalayas. The annual yield of O. sinensis has gradually declined in recent years. However, there is no effective method to sustain or increase the yield of O. sinensis artificially because the life cycle of the O. sinensis anamorph remains unclear. Here we detected O. sinensis in alpine plant roots by nested-touchdown polymerase chain reaction (PCR). Forty-two alpine plant species were screened. The roots from 23 alpine plant species (54.76 %) tested positive including 13 families and 18 genera. The detection results indicate that O. sinensis is present in the plant roots during the anamorph life cycle, to deal with harsh conditions in alpine habitats and have an increased opportunity to infect the larvae. The finding provides new information regarding the biology and ecology of O. sinensis that may be used to sustain this valuable resource. (C) 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved. C1 [Zhong, Xin; Peng, Qing-yun; Li, Shao-Song; Chen, Hai; Sun, Hong-Xia; Zhang, Gu-Ren; Liu, Xin] Sun Yat Sen Univ, Food & Hlth Engn Res Ctr, Sch Life Sci, State Educ Minist, Guangzhou 510275, Guangdong, Peoples R China. RP Liu, X (通讯作者)，Sun Yat Sen Univ, Food & Hlth Engn Res Ctr, Sch Life Sci, State Educ Minist, Guangzhou 510275, Guangdong, Peoples R China. EM lsslx@mail.sysu.edu.cn TC 20 Z9 23 PD APR PY 2014 VL 118 IS 4 BP 359 EP 363 DI 10.1016/j.funbio.2013.12.005 UT WOS:000336116200001 DA 2023-03-23 ER PT J AU Zhang, BZ Cai, GJ Wang, HT Li, D Yang, XJ An, XL Zheng, XW Tian, Y Zheng, W Zheng, TL AF Zhang, Bangzhou Cai, Guanjing Wang, Haitao Li, Dong Yang, Xujun An, Xinli Zheng, Xiaowei Tian, Yun Zheng, Wei Zheng, Tianling TI Streptomyces alboflavus RPS and Its Novel and High Algicidal Activity against Harmful Algal Bloom Species Phaeocystis globosa SO PLOS ONE DT Article AB Phaeocystis globosa blooms have frequently occurred along coastal waters and exerted serious impacts on ecological environments by releasing toxic hemolytic substances, forming nuisance foam, and causing oxygen depletion. An actinomycete strain RPS with high algicidal activity against P. globosa was isolated and identified as Streptomyces alboflavus, based on morphology, physiological and biochemical characteristics, and 16S rDNA sequence analysis. RPS lysed 95% of P. globosa within 48 h by releasing an extracellular active substance into the growth medium. The activity of RPS supernatant was sensitive to temperature at and above 50 degrees C and insensitive to pH from 3 to 11. The molecular weight of the active substance was between 100 Da and 1000 Da, and approximately 90% of it was extracted by ethyl acetate. It was presumed that the active component efficiently inhibited the movement of P. globosa, caused the flagella to fall off the algae, and finally lysed the algal cells. RPS showed a wide target range against harmful algae. S. alboflavus RPS with high algicidal activity and such novel features of temperature and pH sensitivity, low molecular weight, algicidal process, and target range possesses great potential in the biological control of P. globosa blooms. C1 [Zheng, Wei] Xiamen Univ, Sch Life Sci, State Key Lab Marine Environm Sci, Xiamen, Fujian, Peoples R China. Xiamen Univ, Sch Life Sci, Key Lab, Minist Educ, Xiamen, Fujian, Peoples R China. RP Zheng, W (通讯作者)，Xiamen Univ, Sch Life Sci, State Key Lab Marine Environm Sci, Xiamen, Fujian, Peoples R China. EM jedi@xmu.edu.cn; microzh@xmu.edu.cn TC 62 Z9 78 PD MAR 27 PY 2014 VL 9 IS 3 AR e92907 DI 10.1371/journal.pone.0092907 UT WOS:000333677500054 DA 2023-03-23 ER PT J AU Pan, Y Wu, JX Xu, ZR AF Pan, Ying Wu, Junxi Xu, Zengrang TI Analysis of the tradeoffs between provisioning and regulating services from the perspective of varied share of net primary production in an alpine grassland ecosystem SO ECOLOGICAL COMPLEXITY DT Article AB Because ecosystems are complex, tradeoffs exist among supplies of multiple ecosystem services, especially between the provisioning and regulating services. In ecosystem processes, net primary production (NPP) is connected with many other processes such as respiration and evapotranspiration. As one key supporting service, NPP is also related to other provisioning and regulating services. This study introduces an analysis framework of ecosystem services tradeoffs from the perspective of varied share of NPP, in the alpine grassland ecosystem of Damxung County on the Tibetan plateau, China. Total NPP was divided into the share of NPP spent on supplying provisioning services and the share used in supporting regulating services. Tradeoffs between provisioning and regulating services were analyzed by quantifying the change of meat provisioning service and the remaining share of NPP used in other ways; the corresponding change in the share of NPP used to support regulating services was also analyzed and compared with other changes in regulating services, such as carbon sequestration and water conservation services. The results show, from 2000 to 2010, the meat provisioning service increased by 199%, but this was at a cost of additional livestock feeding, which used more NPP of the alpine grassland ecosystem. As a result, by 2010 the remaining NPP used for supporting regulating services shrank to 77% of the 2000 level, which was accompanied by a decrease in carbon sequestration and water conservation services by 90% and 67%, respectively. The analysis of tradeoffs from the perspective of variations in the share of NPP used for various services will contribute to the study of mechanisms involved in providing ecosystem services, interactions between the provisioning of various services, and will also help land managers improve the management of ecosystems. Published by Elsevier B.V. C1 [Pan, Ying; Wu, Junxi; Xu, Zengrang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. RP Wu, JX (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Datun Rd 11A, Beijing 100101, Peoples R China. EM wujx@igsnrr.ac.cn TC 39 Z9 52 PD MAR PY 2014 VL 17 BP 79 EP 86 DI 10.1016/j.ecocom.2013.11.001 UT WOS:000331679000008 DA 2023-03-23 ER PT J AU Thapa, BB Panthi, S Rai, RK Shrestha, UB Aryal, A Shrestha, S Shrestha, B AF Thapa, Barna Bahadur Panthi, Saroj Rai, Rajesh Kumar Shrestha, Uttam Babu Aryal, Achyut Shrestha, Sabina Shrestha, Bhushan TI An assessment of Yarsagumba (Ophiocordyceps sinensis) collection in Dhorpatan Hunting Reserve, Nepal SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Yarsagumba (Ophiocordyceps sinensis), an endemic species to the Himalayas and Tibetan Plateau, is one of the most valuable medicinal mushrooms in the world. In Nepal, it is distributed largely in isolated patches of alpine grasslands of 3,000-5,000 m elevation. Although it is reported from 27 northernmost districts of Nepal, the local distribution pattern of this species is largely unknown. Furthermore, the collection system and local management regime of this species are not well documented. We conducted a field survey at Dhorpatan Hunting Reserve (DHR) among the different stakeholders in January-June 2012 to assess collection sites, patterns and trends and to understand the management regime. We estimated that about 75 kg of Yarsagumba is collected every year from DHR and the amount has been declining since 2008. To manage the resource, locals have initiated regulating the collection by issuing permits, taxing to the collectors, and monitoring the activities of harvesters with the help of park authorities. The revenue generated at local level from the permits has been used for community developmental activities. C1 [Thapa, Barna Bahadur] Babar Mahal, Dept Natl Parks & Wildlife Conservat, Kathmandu 44600, Nepal. [Panthi, Saroj] Dhorpatan Hunting Reserve, Baglung Stn, Baglung 33300, Nepal. [Rai, Rajesh Kumar] Green Governance Nepal, Kathmandu 44600, Nepal. [Shrestha, Uttam Babu] Univ Massachusetts, Dept Biol, Boston, MA 02125 USA. [Aryal, Achyut] Massey Univ, Inst Nat & Math Sci, Auckland 0745, New Zealand. [Shrestha, Sabina] Kyung Hee Univ, Inst Life Sci & Resources, Grad Sch Biotechnol, Yongin 446701, South Korea. [Shrestha, Sabina; Shrestha, Bhushan] Green Energy Mission Nepal, Kathmandu 44600, Nepal. [Shrestha, Bhushan] Rural Dev Adm, Mushroom Res Div, Natl Inst Hort & Herbal Sci, Suwon 441707, South Korea. RP Shrestha, B (通讯作者)，Green Energy Mission Nepal, POB 10647, Kathmandu 44600, Nepal. EM barnathapa@gmail.com; bhushanshrestha2004@yahoo.com TC 15 Z9 15 PD MAR PY 2014 VL 11 IS 2 BP 555 EP 562 DI 10.1007/s11629-013-2692-7 UT WOS:000332968800024 DA 2023-03-23 ER PT J AU Wu, GL Ren, GH Dong, QM Shi, JJ Wang, YL AF Wu, Gao-Lin Ren, Guo-Hua Dong, Quan-Min Shi, Jian-Jun Wang, Yan-Long TI Above- and Belowground Response along Degradation Gradient in an Alpine Grassland of the Qinghai- Tibetan Plateau SO CLEAN-SOIL AIR WATER DT Article AB Grassland degradation is one of the worldwide ecological problems. The objective of this study was to assess the above- and belowground response of an alpine grassland along degradation gradient in the headwater areas of the Qinghai-Tibetan Plateau. Results showed that aboveground biomass, cover, and high quality herbage percentage presented a decreasing trend along degradation gradient. But, species number, species diversity, and evenness showed the maximum value in moderate degraded grassland, and the minimum value was appeared in the extreme degraded grassland. Similarity index was the maximum between original vegetation and light degradation grassland. And the similarity index between light degradation and moderate degradation, between original vegetation and moderate degradation were significantly different. Meanwhile, soil hardness, pH value, soil moisture, available nitrogen, available phosphorus, and available potassium, all showed the decreased trend along the grassland degradation gradient. Grassland degradation led to a decrease of soil physics and chemical properties. Our results predicted that there was also a degradation of soil properties when community structure and composition degraded along the grassland degradation gradient. C1 [Wu, Gao-Lin] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Ren, Guo-Hua; Dong, Quan-Min; Shi, Jian-Jun; Wang, Yan-Long] Qinghai Acad Anim & Vet Sci, Key Lab Alpine Grassland Ecosyst Three River Head, Xining, Qinghai, Peoples R China. [Ren, Guo-Hua; Dong, Quan-Min; Shi, Jian-Jun; Wang, Yan-Long] Qinghai Acad Anim & Vet Sci, Minist Educ, Xining, Qinghai, Peoples R China. RP Wu, GL (通讯作者)，Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. EM gaolinwu@gmail.com; dqm850@sina.com TC 47 Z9 57 PD MAR PY 2014 VL 42 IS 3 BP 319 EP 323 DI 10.1002/clen.201200084 UT WOS:000332379100014 DA 2023-03-23 ER PT J AU Miehe, G Miehe, S Bohner, J Kaiser, K Hensen, I Madsen, D Liu, JQ Opgenoorth, L AF Miehe, Georg Miehe, Sabine Boehner, Juergen Kaiser, Knut Hensen, Isabel Madsen, David Liu, JianQuan Opgenoorth, Lars TI How old is the human footprint in the world's largest alpine ecosystem? A review of multiproxy records from the Tibetan Plateau from the ecologists' viewpoint SO QUATERNARY SCIENCE REVIEWS DT Review AB The age at which a human environment was made is strongly debated in Quaternary science. The perception of the human footprint requires an understanding of the contrast between the present cultural environment and the natural vegetation. This is especially true for high altitude ecosystems, such as the world's largest alpine ecosystem, the 450,000 km(2) of golf-course-like pastures dominating the southeastern Tibetan Plateau. This ecosystem is widely considered to be natural, but only because of the unawareness of the effects of grazing management and the incorrect assessment of human signals in palaeo proxies. Here we posit the hypothesis that this ecosystem is a human-induced replacement. To test our hypothesis against defined a priori criteria, we 1) monitored vegetation in grazing exclosures; 2) produced floristically complete vegetation records; 3) compared the vegetation records with data of the nearest climate stations; 4) surveyed forest and experimental reforestation trials with endemic tree species; 5) analyzed pollen and re-evaluated published pollen diagrams; and 6) integrated these results with palaeopedological and anthracological results of previous studies. The results of long-term grazing exclosure experiments, the prevalence of grazing-adapted plant functional types, the occurrence of isolated vigorous forests in "alpine" pastures, and the successful reforestation trials in presently treeless pastures together suggest that dominant pastures replaced forests in the montane belt and tall grassland in the alpine belt. The spatial and temporal coincidence of palaeosols and archaeological sites with tree species charcoal, the decline in forest pollen during the mid-Holocene climatic optimum, and the first appearance of human indicator pollen are most parsimoniously explained by the early presence of foragers and pastoralists. The onset of pastoralism in the Tibetan Highlands is presumed to date from the 8th millennium BP. (C) 2013 Elsevier Ltd. All rights reserved. C1 [Miehe, Georg; Miehe, Sabine] Univ Marburg, Fac Geog, D-35032 Marburg, Germany. [Boehner, Juergen] Univ Hamburg, Inst Geog, D-20146 Hamburg, Germany. [Kaiser, Knut] Deutsch GeoForsch Zentrum GFZ, D-14473 Potsdam, Germany. [Hensen, Isabel] Univ Halle Wittenberg, Inst Geobot, D-06108 Halle, Germany. [Madsen, David] Univ Texas Austin, TARL, Austin, TX 78712 USA. [Liu, JianQuan] Lanzhou Univ, Coll Life Sci, State Key Lab Grassland Agriecosyst, Lanzhou 730000, Gansu, Peoples R China. [Opgenoorth, Lars] Univ Marburg, Dept Ecol, Fac Biol, D-35043 Marburg, Germany. RP Miehe, G (通讯作者)，Univ Marburg, Fac Geog, Deutschhausstrasse 10, D-35032 Marburg, Germany. EM miehe@uni-marburg.de; opgenoorth@uni-marburg.de TC 100 Z9 104 PD FEB 15 PY 2014 VL 86 BP 190 EP 209 DI 10.1016/j.quascirev.2013.12.004 UT WOS:000331991100014 DA 2023-03-23 ER PT J AU Xiao, XY Haberle, SG Shen, J Yang, XD Han, Y Zhang, EL Wang, SM AF Xiao, Xiayun Haberle, Simon G. Shen, Ji Yang, Xiangdong Han, Yong Zhang, Enlou Wang, Sumin TI Latest Pleistocene and Holocene vegetation and climate history inferred from an alpine lacustrine record, northwestern Yunnan Province, southwestern China SO QUATERNARY SCIENCE REVIEWS DT Article AB Reconstructing past changes of the summer monsoon in southwestern China is key to understanding the paleoclimatic dynamics of the Indian summer monsoon (southwest monsoon), a major tropical system with impacts beyond the region. High-resolution pollen and conifer stoma data are presented from a sediment core (Tiancai Lake), located just below treeline in the Hengduan Mountains, northwestern Yunnan Province of China. These data record changes in vegetation and climate for the latest Pleistocene and Holocene (c. the last 12,230 cal. yr BP), and by comparing these results with the pollen records from the nearby Erhai Lake and Lugu Lake, a regional climate history in Yunnan Province can be inferred. During the period of 12,230-11,510 cal. yr BP, open alpine meadow around Tiancai Lake indicates a relatively cold and dry climate, corresponding to the Younger Dryas cold event (YD). Between 11,510 and 10,000 cal. yr BP, the vegetation types around Tiancai Lake changed into Picea and Abies forest and alpine Rhododendron shrubland, reflecting increases in the temperature and humidity. From similar to 10,000 to 6100 cal. yr BP, Tsuga forest expanded persistently toward Tiancai Lake, indicating further climate changed towards warmer and wetter conditions. Between 6100 and 3410 cal. yr BP, Tsuga forest was the dominant vegetation type nearest to Tiancai Lake, denoting warm and humid climatic conditions, corresponding to the Holocene climatic optimum in the northwestern Yunnan Province. Tsuga forest in mountains around Lugu Lake shrank quickly at 3410 cal. yr BP, reflecting significant decline of humidity. Since 2930 cal. yr BP, Tsuga forest around Tiancai Lake shrank gradually, indicating a fluctuating decrease of temperature. These climatic changes reflect changes of the southwest monsoon, namely, warm and humid climate indicating strong southwest monsoon, cold and dry climate denoting weak southwest monsoon. (C) 2013 Elsevier Ltd. All rights reserved. C1 [Xiao, Xiayun; Shen, Ji; Yang, Xiangdong; Zhang, Enlou; Wang, Sumin] Chinese Acad Sci, Nanjing Inst Geog & Limnol, State Key Lab Lake Sci & Environm, Nanjing 210008, Jiangsu, Peoples R China. [Haberle, Simon G.] Australian Natl Univ, Coll Asia & Pacific, Dept Archaeol & Nat Hist, Canberra, ACT 0200, Australia. [Han, Yong] Nanjing Univ, Sch Atmospher Sci, Nanjing 210093, Jiangsu, Peoples R China. RP Xiao, XY (通讯作者)，Chinese Acad Sci, Nanjing Inst Geog & Limnol, State Key Lab Lake Sci & Environm, Nanjing 210008, Jiangsu, Peoples R China. EM xyxiao@niglas.ac.cn; jishen@niglas.ac.cn TC 134 Z9 163 PD FEB 15 PY 2014 VL 86 BP 35 EP 48 DI 10.1016/j.quascirev.2013.12.023 UT WOS:000331991100004 DA 2023-03-23 ER PT J AU Gao, QZ Li, Y Xu, HM Wan, YF Jiangcun, WZ AF Gao, Qing-zhu Li, Yue Xu, Hong-mei Wan, Yun-fan Jiangcun, Wang-zha TI Adaptation strategies of climate variability impacts on alpine grassland ecosystems in Tibetan Plateau SO MITIGATION AND ADAPTATION STRATEGIES FOR GLOBAL CHANGE DT Article AB Northern Tibet is the headstream region for the Yangtze, Salween River, Mekong River, and numerous other inflowing rivers and high mountain lakes. Sustaining the environmental conditions in the region is of vital importance for Tibet and the whole of China. The alpine grassland ecosystem in Northern Tibet is the most important ecosystem and extremely sensitive to climate change and human activity. In this study, we analyzed the characteristics of climate variability based on observed meteorological data and future climate scenarios, and reviewed the impact of climate variability and to explore adaptation strategies of alpine grassland in Northern Tibet. The result showed that the annual mean temperature has increased by 0.31 A degrees C center dot 10a(-1) while the annual total precipitation has increased by 14.6 mm center dot 10a(-1) with high inter-annual and inter-seasonal fluctuations in Northern Tibet from 1961 to 2008. The rising trends of temperature and precipitation would be continued and the aridity indices showed a decreasing trend in the future, which potentially predicts that the climate in Northern Tibet becomes warmer and dryer. The climate variability results the melting of glaciers, the expansion of inland high mountain lakes and the negative impacts on alpine grassland in recent years. In order to adapt to such possible future climate changes, the alpine grassland water-saving irrigation was recommended as key adaptation measure and also rational grazing management, alpine grassland fencing and artificial grass planting were selected as adaptation measures, to lower the negative impacts of climate variability on the alpine grassland ecosystem in Northern Tibet. C1 [Gao, Qing-zhu; Li, Yue; Wan, Yun-fan] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Gao, Qing-zhu; Li, Yue; Wan, Yun-fan] Minist Agr, Key Lab Agroenvironm & Climate Change, Beijing 100081, Peoples R China. [Xu, Hong-mei] China Meteorol Adm, Natl Climate Ctr, Beijing 100081, Peoples R China. [Jiangcun, Wang-zha] Nagqu Grassland Stn, Nagqu 852100, Tibet Autonomou, Peoples R China. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM gaoqzh@ami.ac.cn TC 35 Z9 44 PD FEB PY 2014 VL 19 IS 2 BP 199 EP 209 DI 10.1007/s11027-012-9434-y UT WOS:000329791200005 DA 2023-03-23 ER PT J AU Zhang, XF Xu, SJ Li, CM Zhao, L Feng, HY Yue, GY Ren, ZW Cheng, GD AF Zhang, Xinfang Xu, Shijian Li, Changming Zhao, Lin Feng, Huyuan Yue, Guangyang Ren, Zhengwei Cheng, Guogdong TI The soil carbon/nitrogen ratio and moisture affect microbial community structures in alkaline permafrost-affected soils with different vegetation types on the Tibetan plateau SO RESEARCH IN MICROBIOLOGY DT Article AB In the Tibetan permafrost region, vegetation types and soil properties have been affected by permafrost degradation, but little is known about the corresponding patterns of their soil microbial communities. Thus, we analyzed the effects of vegetation types and their covariant soil properties on bacterial and fungal community structure and membership and bacterial community-level physiological patterns. Pyrosequencing and Biolog EcoPlates were used to analyze 19 permafrost-affected soil samples from four principal vegetation types: swamp meadow (SM), meadow (M), steppe (S) and desert steppe (DS). Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria dominated bacterial communities and the main fungal phyla were Ascomycota, Basidiomycota and Mucoromycotina. The ratios of ProteobacterialAcidobacteria decreased in the order: SM > M > S > DS, whereas the Ascomycota/Basidiomycota ratios increased. The distributions of carbon and nitrogen cycling bacterial genera detected were related to soil properties. The bacterial communities in SM/M soils degraded amines/amino acids very rapidly, while polymers were degraded rapidly by S/DS communities. UniFrac analysis of bacterial communities detected differences among vegetation types. The fungal UniFrac community patterns of SM differed from the others. Redundancy analysis showed that the carbon/nitrogen ratio had the main effect on bacteria community structures and their diversity in alkaline soil, whereas soil moisture was mainly responsible for structuring fungal communities. Thus, microbial communities and their functioning are probably affected by soil environmental change in response to permafrost degradation. (C) 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved. C1 [Zhang, Xinfang; Xu, Shijian; Li, Changming; Feng, Huyuan; Ren, Zhengwei] Lanzhou Univ, Sch Life Sci, MOE Key Lab Cell Activ & Stress Adaptat, Lanzhou 730000, Gansu, Peoples R China. [Zhang, Xinfang; Zhao, Lin; Yue, Guangyang; Cheng, Guogdong] Chinese Acad Sci, Cold & Arid Regions Environm & Engn Res Inst, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China. RP Xu, SJ (通讯作者)，Lanzhou Univ, Sch Life Sci, MOE Key Lab Cell Activ & Stress Adaptat, Lanzhou 730000, Gansu, Peoples R China. EM Zhangxinfang@lzu.edu.cn TC 87 Z9 102 PD FEB-MAR PY 2014 VL 165 IS 2 BP 128 EP 139 DI 10.1016/j.resmic.2014.01.002 UT WOS:000347590900008 DA 2023-03-23 ER PT J AU Babel, W Biermann, T Coners, H Falge, E Seeber, E Ingrisch, J Schleuss, PM Gerken, T Leonbacher, J Leipold, T Willinghofer, S Schutzenmeister, K Shibistova, O Becker, L Hafner, S Spielvogel, S Li, X Xu, X Sun, Y Zhang, L Yang, Y Ma, Y Wesche, K Graf, HF Leuschner, C Guggenberger, G Kuzyakov, Y Miehe, G Foken, T AF Babel, W. Biermann, T. Coners, H. Falge, E. Seeber, E. Ingrisch, J. Schleuss, P. -M. Gerken, T. Leonbacher, J. Leipold, T. Willinghoefer, S. Schuetzenmeister, K. Shibistova, O. Becker, L. Hafner, S. Spielvogel, S. Li, X. Xu, X. Sun, Y. Zhang, L. Yang, Y. Ma, Y. Wesche, K. Graf, H. -F. Leuschner, C. Guggenberger, G. Kuzyakov, Y. Miehe, G. Foken, T. TI Pasture degradation modifies the water and carbon cycles of the Tibetan highlands SO BIOGEOSCIENCES DT Article AB The Tibetan Plateau has a significant role with regard to atmospheric circulation and the monsoon in particular. Changes between a closed plant cover and open bare soil are one of the striking effects of land use degradation observed with unsustainable range management or climate change, but experiments investigating changes of surface properties and processes together with atmospheric feedbacks are rare and have not been undertaken in the world's two largest alpine ecosystems, the alpine steppe and the Kobresia pygmaea pastures of the Tibetan Plateau. We connected measurements of micro-lysimeter, chamber, C-13 labelling, and eddy covariance and combined the observations with land surface and atmospheric models, adapted to the highland conditions. This allowed us to analyse how three degradation stages affect the water and carbon cycle of pastures on the landscape scale within the core region of the Kobresia pygmaea ecosystem. The study revealed that increasing degradation of the Kobresia turf affects carbon allocation and strongly reduces the carbon uptake, compromising the function of Kobresia pastures as a carbon sink. Pasture degradation leads to a shift from transpiration to evaporation while a change in the sum of evapotranspiration over a longer period cannot be confirmed. The results show an earlier onset of convection and cloud generation, likely triggered by a shift in evapotranspiration timing when dominated by evaporation. Consequently, precipitation starts earlier and clouds decrease the incoming solar radiation. In summary, the changes in surface properties by pasture degradation found on the highland have a significant influence on larger scales. C1 [Babel, W.; Biermann, T.; Falge, E.; Gerken, T.; Leonbacher, J.; Leipold, T.; Foken, T.] Univ Bayreuth, Dept Micrometeorol, Bayreuth, Germany. [Coners, H.; Willinghoefer, S.; Leuschner, C.] Univ Gottingen, Dept Plant Ecol & Ecosyst Res, D-37073 Gottingen, Germany. [Seeber, E.; Wesche, K.] Senckenberg Museum Gorlitz, Dept Bot, Gorlitz, Germany. [Ingrisch, J.; Schleuss, P. -M.; Hafner, S.; Spielvogel, S.; Xu, X.; Sun, Y.; Kuzyakov, Y.] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, D-37073 Gottingen, Germany. [Gerken, T.; Graf, H. -F.] Univ Cambridge, Dept Geog, Ctr Atmospher Sci, Cambridge CB2 3EN, England. [Schuetzenmeister, K.; Spielvogel, S.] Univ Koblenz Landau, Inst Integrated Environm Sci, Koblenz, Germany. [Shibistova, O.; Becker, L.; Guggenberger, G.] Leibniz Univ Hannover, Hannover, NH, Germany. [Shibistova, O.] VN Sukachev Inst Forest, Krasnoyarsk, Russia. [Li, X.] Lanzhou Univ, Sch Life Sci, Lanzhou 730000, Peoples R China. [Xu, X.; Sun, Y.] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China. [Zhang, L.; Ma, Y.] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface, Beijing, Peoples R China. [Yang, Y.] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers Focuses, Beijing, Peoples R China. [Wesche, K.] German Ctr Integrat Biodivers Res iDiv, Halle Jena Leipzig, Germany. [Kuzyakov, Y.] Univ Gottingen, Dept Agr Soil Sci, D-37073 Gottingen, Germany. [Kuzyakov, Y.] Kazan Fed Univ, Inst Environm Sci, Kazan, Russia. [Miehe, G.] Univ Marburg, Marburg, Germany. [Ingrisch, J.] Univ Innsbruck, Inst Ecol Res, Innsbruck, Austria. RP Foken, T (通讯作者)，Univ Bayreuth, Dept Micrometeorol, Bayreuth, Germany. EM thomas.foken@uni-bayreuth.de TC 67 Z9 71 PY 2014 VL 11 IS 23 BP 6633 EP 6656 DI 10.5194/bg-11-6633-2014 UT WOS:000346357100009 DA 2023-03-23 ER PT J AU Chang, XF Zhu, XX Wang, SP Cui, SJ Luo, CY Zhang, ZH Wilkes, A AF Chang, X. F. Zhu, X. X. Wang, S. P. Cui, S. J. Luo, C. Y. Zhang, Z. H. Wilkes, A. TI Impacts of management practices on soil organic carbon in degraded alpine meadows on the Tibetan Plateau SO BIOGEOSCIENCES DT Article AB Grassland soil organic carbon (SOC) is sensitive to anthropogenic activities. Increased anthropogenic disturbance related to overgrazing has led to widespread alpine grassland degradation on the Tibetan Plateau. The degraded grasslands are considered to have great potential for carbon sequestration after adoption of improved management practices. Here, we calibrated and employed the Century model to investigate the effects of overgrazing and improved managements on the SOC dynamics in alpine meadows. We calibrated the Century model against plant productivity at the Haibei Research Station. SOC stocks for validation were obtained in 2009-2010 from degraded alpine meadows in two communes. We found that Century model can successfully capture grassland SOC changes. Overall, our simulation suggests that degraded alpine meadow SOC significantly increased with the advent of restoration management from 2011 to 2030. Carbon sequestration rates ranged between 0.04 Mg C ha(-1) yr(-1) in lightly degraded winter grazing grasslands and 2.0 Mg C ha(-1) yr(-1) in moderately degraded summer grazing grasslands. Our modelling work also predicts that improve management in degraded Tibetan grasslands will contribute to an annual carbon sink of 0.022-0.059 Pg C yr(-1). These results imply that restoration of degraded grasslands in the Tibetan Plateau has great potential for soil carbon sequestration to mitigate greenhouse gases. C1 [Chang, X. F.; Wang, S. P.] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. [Chang, X. F.] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Inst Soil & Water Conservat, Yangling 712100, Peoples R China. [Zhu, X. X.; Cui, S. J.; Luo, C. Y.; Zhang, Z. H.] Chinese Acad Sci, Northwest Inst Plateau Biol, Haibei Alpine Meadow Ecosyst Res Stn, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Zhu, X. X.; Cui, S. J.] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. [Wilkes, A.] Chinese Acad Sci, Kunming Inst Bot, Ctr Mt Ecosyst Studies, Kunming 650201, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, 16 Lincui Rd, Beijing 100101, Peoples R China. EM wangsp@itpcas.ac.cn TC 22 Z9 28 PY 2014 VL 11 IS 13 BP 3495 EP 3503 DI 10.5194/bg-11-3495-2014 UT WOS:000339265800005 DA 2023-03-23 ER PT J AU Cui, GW Li, HY Sun, T Wang, Z Xi, LQ AF Cui, Guo-Wen Li, Hong-Ying Sun, Tao Wang, Zha Xi, Lin-Qiao TI An Experimental Study of Variety Screening, Sequential Cropping, Compaction and Mixed Cropping Techniques for the Cultivation of Annual Forage Crops in Agro-pastoral Area of Tibet, China SO INTERNATIONAL JOURNAL OF AGRICULTURE AND BIOLOGY DT Article AB Field experiments were conducted in Jangdam, in the Tibetan plateau of China, to investigate the forage production potential of oats (Avena sativa L.), forage-type triticale (xTriticosecale Wittmack) and common vetch (Vicia sativa L.). The forage productivity of oats and forage-type triticale were evaluated in comparison with local naked barley (Hordeum vulgare L.) in single and sequential cropping systems, with and without a compaction roller. The effect of mixed cropping oats with common vetch on the yield and quality of forages was also examined for different seeding ratios. Hay yield, seed germination, and crude protein content were determined for each of the cropping systems. The results revealed that oats and forage-type triticale produced a significantly higher hay yield than local naked barley in both single and sequential cropping systems. Sequential cropping significantly enhanced the total forage yield to 12.4 Mg ha(-1) for oats, compared to single cropping (8.7 Mg ha(-1)). The seed germination percentage was significantly increased in compacted soil after sowing, which also leads to higher hay yield. Mixed sowing of oats with common vetch brought a protein-rich harvest with a higher or equivalent yield than single-sown oats. The crude protein concentration of the whole forage decreased with the decrease in the seeding ratio of common vetch; the seeding ratio of 70% oat and 100% common vetch achieved a higher forage yield and protein content than the other mixtures studied. (C) 2014 Friends Science Publishers C1 [Cui, Guo-Wen; Li, Hong-Ying; Sun, Tao; Xi, Lin-Qiao] Northeast Agr Univ, Coll Anim Sci & Technol, Harbin 150030, Peoples R China. [Wang, Zha] Shigatse Sci & Technol Bur, Shigatse 857000, Peoples R China. RP Cui, GW (通讯作者)，Northeast Agr Univ, Coll Anim Sci & Technol, Harbin 150030, Peoples R China. EM cgw603@163.com TC 0 Z9 1 PY 2014 VL 16 IS 1 BP 97 EP 103 UT WOS:000331620400013 DA 2023-03-23 ER PT J AU Jing, X Wang, YH Chung, HG Mi, ZR Wang, SP Zeng, H He, JS AF Jing, Xin Wang, Yonghui Chung, Haegeun Mi, Zhaorong Wang, Shiping Zeng, Hui He, Jin-Sheng TI No temperature acclimation of soil extracellular enzymes to experimental warming in an alpine grassland ecosystem on the Tibetan Plateau SO BIOGEOCHEMISTRY DT Article AB Alpine grassland soils store large amounts of soil organic carbon (SOC) and are susceptible to rising air temperature. Soil extracellular enzymes catalyze the rate-limiting step in SOC decomposition and their catalysis, production and degradation rates are regulated by temperature. Therefore, the responses of these enzymes to warming could have a profound impact on carbon cycling in the alpine grassland ecosystems. This study was conducted to measure the responses of soil extracellular enzyme activity and temperature sensitivity (Q(10)) to experimental warming in samples from an alpine grassland ecosystem on the Tibetan Plateau. A free air-temperature enhancement system was set up in May 2006. We measured soil microbial biomass, nutrient availability and the activity of five extracellular enzymes in 2009 and 2010. The Q(10) of each enzyme was calculated using a simple first-order exponential equation. We found that warming had no significant effects on soil microbial biomass C, the labile C or N content, or nutrient availability. Significant differences in the activity of most extracellular enzymes among sampling dates were found, with typically higher enzyme activity during the warm period of the year. The effects of warming on the activity of the five extracellular enzymes at 20 A degrees C were not significant. Enzyme activity in vitro strongly increased with temperature up to 27 A degrees C or over 30 A degrees C (optimum temperature; T-opt). Seasonal variations in the Q(10) were found, but the effects of warming on Q(10) were not significant. We conclude that soil extracellular enzymes adapted to seasonal temperature variations, but did not acclimate to the field experimental warming. C1 [Jing, Xin; Wang, Yonghui; Zeng, Hui; He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. [Jing, Xin; Wang, Yonghui; Zeng, Hui; He, Jin-Sheng] Peking Univ, Minist Educ, Key Lab Earth Surface Proc, Beijing 100871, Peoples R China. [Chung, Haegeun] Konkuk Univ, Dept Environm Engn, Seoul 143701, South Korea. [Mi, Zhaorong; He, Jin-Sheng] Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, Beijing 100085, Peoples R China. [Zeng, Hui] Peking Univ, Shenzhen Grad Sch, Key Lab Urban Habitat Environm Sci & Technol, Shenzhen 518055, Peoples R China. RP He, JS (通讯作者)，Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, 23 Xinning Rd, Xining 810008, Peoples R China. EM jshe@nwipb.cas.cn TC 55 Z9 73 PD JAN PY 2014 VL 117 IS 1 BP 39 EP 54 DI 10.1007/s10533-013-9844-2 UT WOS:000329606200004 DA 2023-03-23 ER PT J AU Li, YY Dong, SK Wen, L Wang, XX Wu, Y AF Li, Yuan-Yuan Dong, Shi-Kui Wen, Lu Wang, Xue-Xia Wu, Yu TI Soil carbon and nitrogen pools and their relationship to plant and soil dynamics of degraded and artificially restored grasslands of the Qinghai-Tibetan Plateau SO GEODERMA DT Article AB Land disturbances and management approaches can significantly alter the restoration of degraded grasslands. Therefore, understanding the carbon and nitrogen storage accompanying plant and soil physical and chemical properties due to anthropogenic disturbance and different management strategies is important, as it can help us understand not only how ecosystem responds to its dynamics but also the restoration effects of restoration methods. In our study, we investigated carbon, nitrogen storage, plant community alterations and other soil chemical and physical properties regarding artificial grasslands with different restoration years and native grasslands with different degradation levels. We found that artificial grassland establishment significantly increased above- and belowground biomass, but the richness, diversity and evenness indexes had a decreasing trend compared with extremely degraded grasslands. Grazing also had a negative effect on plant communities and diversity indexes. The soil organic carbon (SOC) was highest in non-degraded grasslands (ND). The SOC content had decreased 21.89%, 3830% and 43.15% with the increase of the grassland degradation compared with ND. The total nitrogen (TN) content was also higher in the ND (0.955 kg.m(-2)) than in either degraded grasslands (0.908 kg.m(-2), 0.786 kg.m(-2), and 0.769 kg.m(-2) for moderately, heavily and extremely degraded, respectively). The total carbon, SOC and TN content were concentrated on the 0-4 cm depth, accounting for more than 50% of the total content We also found that the soil nutrients substantially decreased with increasing restoration years. Furthermore, soil nutrients had a close relationship with plant and soil factors, as reflected by a correlation index. The above-mentioned results indicated that artificial grasslands can be used as an effective method to restore "black-beach" soil grassland. In the long term, however, management interventions should be implemented to prevent the degradation of artificial grasslands. (C) 2013 Elsevier B.V. All rights reserved. C1 [Li, Yuan-Yuan; Dong, Shi-Kui; Wen, Lu; Wang, Xue-Xia; Wu, Yu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 108 Z9 122 PD JAN PY 2014 VL 213 BP 178 EP 184 DI 10.1016/j.geoderma.2013.08.022 UT WOS:000329594800021 DA 2023-03-23 ER PT J AU Lu, JF Dong, ZB Li, WJ Hu, GY AF Lu, Junfeng Dong, Zhibao Li, Wenjin Hu, Guangyin TI The effect of desertification on carbon and nitrogen status in the northeastern margin of the Qinghai-Tibetan Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB Environmental degradation resulting from desertification often accelerates biodiversity loss and alters carbon (C) and nitrogen (N) stocks within grassland ecosystem. In order to evaluate the effect of desertification on plant diversity and carbon (C) and nitrogen (N) stocks, species compositions and C and N contents in plants and soil were investigated along five regions with different degrees of desertification in the northeastern margin of the Qinghai-Tibetan Plateau (control, light, moderate, severe and very severe stages). The study showed: (1) species composition and richness changed significantly with the development of grassland desertification; (2) the aboveground biomass C and N contents in the control were 101.60 and 4.03 g m(-2), respectively. Compared to the control, the aboveground tissue C and N contents significantly decreased from light, moderate, severe to very severe stages. (3) The root C and N contents in the control in 0-40 cm depth are 1,372.83 and 31.49 g m(-2), respectively, while the root C and N contents in 0-40 cm were also declining from the control, light, moderate, severe to very severe stages. (4) Compared to the plant, the soil made a greater contribution for C and N distribution, in which the soil organic C and total N contents in 0-40 cm depth in the control are 20,386.70 and 3,587.89 g m(-2), respectively. At the same time, soil organic C and N contents also decreased significantly from the control to very severe stages. These results suggest that grassland desertification not only alters species compositions and leads to the loss of plant diversity, but also results in greater loss of organic C and N in alpine meadow, in which there is a negative effect on reducing greenhouse gas emission. C1 [Lu, Junfeng; Dong, Zhibao; Hu, Guangyin] Chinese Acad Sci, Key Lab Desert & Desertificat, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Gansu, Peoples R China. [Li, Wenjin] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Sch Life Sci, Lanzhou 730000, Peoples R China. RP Lu, JF (通讯作者)，Chinese Acad Sci, Key Lab Desert & Desertificat, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Gansu, Peoples R China. EM lujunfeng2004@yahoo.com.cn TC 12 Z9 15 PD JAN PY 2014 VL 71 IS 2 SI SI BP 807 EP 815 DI 10.1007/s12665-013-2482-0 UT WOS:000329996200028 DA 2023-03-23 ER PT J AU Luo, MW Mao, L Guo, ZG AF Luo, Ming Wei Mao, Liang Guo, Zheng Gang TI LEAF NITROGEN AND PHOSPHORUS STOICHIOMETRY OF PLANTS FROM NATURAL AND RESTORABLE COMMUNITIES AT LANDS USED FOR QINGHAI-TIBET HIGHWAY CONSTRUCTION, CHINA SO POLISH JOURNAL OF ECOLOGY DT Article AB Highway network construction is one of common factors contributing to alpine grassland degradation in the Qinghai-Tibet Plateau as well as other regions, resulting in big area land used for highway construction by abruptly removing the vegetation and topsoil on both sides of roadbed. Taking the Land Used for Qinghai-Tibet Highway Construction (LUQHC) produced in 1994 as an example, a field survey was conducted to investigate the leaf N, P stoichiometry of plants from natural communities and restorable communities by using all plants and same pairwise of species, because the natural vegetation restoration at LUQHC is driven by element availability to some extent. This study showed that plants were probably P-limited in study region and the variation of N:P ratio was closely related to leaf P concentration. Results of same pairwise of species showed that the leaf N, P and N:P ratio of plants from restorable communities were higher than those of adjacent natural communities, indicating that leaf N and P were simultaneously affected by the environment circumstance of LUQHC. However, results of all species showed that the environment factors only impacted on leaf N concentration. These showed that the plant in restorable communities suffered from more intense P-limited conditions than those in natural communities, and that the same pairwise of species sampling was better to acquire the N- or P-limitation status for plant in restoriable communities than all species. This study also showed that phylogenetic variation (family and genus identity) was key factor affecting the variantions of N, P stoichiometry. C1 [Luo, Ming Wei; Mao, Liang; Guo, Zheng Gang] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, Lanzhou 730020, Peoples R China. RP Guo, ZG (通讯作者)，Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Agroecosyst, POB 61, Lanzhou 730020, Peoples R China. EM guozhg@lzu.edu.cn TC 2 Z9 5 PY 2014 VL 62 IS 2 BP 227 EP 238 DI 10.3161/104.062.0204 UT WOS:000338092500003 DA 2023-03-23 ER PT J AU Shang, ZH Gibb, MJ Leiber, F Ismail, M Ding, LM Guo, XS Long, RJ AF Shang, Z. H. Gibb, M. J. Leiber, F. Ismail, M. Ding, L. M. Guo, X. S. Long, R. J. TI The sustainable development of grassland-livestock systems on the Tibetan plateau: problems, strategies and prospects SO RANGELAND JOURNAL DT Review AB The Tibetan plateau is the source of most of the major rivers of Asia and has a huge impact on the livelihoods of the population, who have for centuries engaged in traditional herding practices. Sustainable management of the plateau is of critical importance not only for maintaining livelihoods but also because of its vital ecological function. The major problem of sustainable development in these grassland-livestock systems is the conflict between forage and livestock production. Despite considerable investment of manpower, material resources and capital over many years, attempts to resolve the problem have not been successful. The magnitude of conflict between forage and livestock is addressed by presenting 19 resolution strategies based on numerous research data. Each of these strategies is evaluated in terms of how it can be implemented, its potential benefits for livestock production, current progress and the requirement for further research. The 19 strategies have been divided into four topic categories, namely; grassland-forage, livestock, economy and market, society-culture, which cover the basic elements of sustainable development in this pastoral region. It is argued that improved planning and implementation of the proposed strategies must be based on the background investigation of natural and social status of the pastoral region. Particular attention needs to be given to genetic resources and technology in order to ensure the successful implementation of these proposals. In addition to expanding the use of 18 currently practiced strategies, the authors propose a further novel strategy of replacing the current intensive form of ecological migration with a model incorporating two semipermanent settlements. The objective of this novel strategy is to retain the nomadic element of pastoral husbandry while increasing the temporal and spatial scale of rotational stocking to reduce pasture degradation on the Tibetan plateau. It is argued that these proposals should be urgently incorporated into two national plans for the pastoral livestock industry, and the construction of an ecologically safe shelter zone on the Tibetan plateau, while ensuring a sustainable livelihood of its pastoral residents. Ensuring a successful implementation of these strategies in resolving the conflict between grassland and livestock, and promoting sustainable development on the Tibetan plateau, requires willing support at the level of national investment and policy commitment and from the herdsmen. C1 [Shang, Z. H.; Long, R. J.] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. [Shang, Z. H.] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. [Gibb, M. J.] Inst Grassland & Environm Res, North Wyke EX20 2SB, Devon, England. [Leiber, F.] FiBL, Dept Livestock Sci, Res Inst Organ Agr, CH-5070 Frick, Switzerland. [Ismail, M.] Int Ctr Integrated Mt Dev, Kathmandu, Nepal. [Ding, L. M.; Guo, X. S.] Lanzhou Univ, State Key Lab Grassland Agroecosyst, Sch Life Sci, Lanzhou 730000, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, State Key Lab Grassland Agroecosyst, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. EM shangzhh@lzu.edu.cn TC 91 Z9 107 PY 2014 VL 36 IS 3 BP 267 EP 296 DI 10.1071/RJ14008 UT WOS:000340270900007 DA 2023-03-23 ER PT J AU Zhang, WJ Lu, QF Song, KC Qin, GH Wang, Y Wang, X Li, HX Li, J Liu, GD Li, H AF Zhang, Wenjiang Lu, Qifeng Song, Kechao Qin, Guanghua Wang, Yan Wang, Xin Li, Hongxia Li, Jun Liu, Guodong Li, Hua TI Remotely sensing the ecological influences of ditches in Zoige Peatland, eastern Tibetan Plateau SO INTERNATIONAL JOURNAL OF REMOTE SENSING DT Article AB Zoige Peatland in the eastern Tibetan Plateau, the largest alpine peatland in China, was widely ditched in 1970s for pasture expansion. The ditching is believed to have caused peatland degradation, but there is still no widespread agreement on this due to the absence of essential regional and temporal information about ditch drainage. Therefore, this study used both remote-sensing observations and field surveys to examine the ecological influences of ditching for this alpine peatland. In the study, ditch distribution was interpreted with remote-sensing imagery and the ecological responses were investigated with temporal observation by Moderate Resolution Imaging Spectroradiometer (MODIS) and field surveys. The results showed that there were similar to 1200 km ditches interpreted, mainly in three spatial patterns depending on hydro-geomorphologies. The MODIS enhanced vegetation index (EVI) was more sensitive to peatland surface water depth (R-2 = 0.678, P < 0.001) than the normalized difference water index (NDWI) (R-2 = 0.583, P < 0.001), because the latter would become saturated at a certain surface water depth (similar to 50 cm in Zoige). The temporal MODIS imagery reflected the ecological responses of ditched peatland to drainage in terms of vegetation density and water conditions. This study indicated that ditching depressed the surface water depth of the Zoige Peatland in summer, but not to the extent of completely transforming peatland into steppe due to the recharging of local beneficial hydro-geomorphologies. The MODIS indices investigated in the study could be used to monitor the annual regional status of vegetation cover and surface water for Zoige peatland. C1 [Zhang, Wenjiang; Song, Kechao; Qin, Guanghua; Wang, Yan; Wang, Xin; Li, Hongxia; Li, Jun; Liu, Guodong] Sichuan Univ, State Key Lab Hydraul & Mt River Engn, Chengdu 61065, Peoples R China. [Lu, Qifeng] Natl Satellite Meteorol Ctr China, Beijing 100081, Peoples R China. [Li, Hua] Adm Zoige Wetland Natl Nat Reserve, Zoige 624500, Peoples R China. RP Lu, QF (通讯作者)，Natl Satellite Meteorol Ctr China, Beijing 100081, Peoples R China. EM luqf@cma.gov.cn TC 21 Z9 28 PY 2014 VL 35 IS 13 BP 5186 EP 5197 DI 10.1080/01431161.2014.939779 UT WOS:000340105700032 DA 2023-03-23 ER PT J AU Zhang, YJ Zhang, XQ Wang, XY Liu, N Kan, HM AF Zhang, Y. J. Zhang, X. Q. Wang, X. Y. Liu, N. Kan, H. M. TI Establishing the carrying capacity of the grasslands of China: a review SO RANGELAND JOURNAL DT Review AB China is rich in grassland resources, with 400x10(6)ha of natural grasslands and 18 main types, mostly distributed in the north-east, north, Qinghai-Tibet Plateau and Xinjiang regions. Grassland-based livestock production is the foundation of the economy in these rural areas. Degradation of grassland has occurred to varying degrees in these regions. Mean overgrazing rates across the whole country were estimated to be similar to 30% in 2009. Considerable amounts of research have focussed, especially since 2000, on developing better ways of managing Chinese grasslands. Research concerning the relationship between forage production and animal performance, is reviewed for three important national grassland regions. For the three major grassland (steppes) types of Inner Mongolia, the stocking rates proposed as a result of research were 1.0-2.2 sheep units (SU) ha(-1) for the western, drier Stipa breviflora desert steppe; 2.0-3.8SUha(-1) for the steppe of Artemisia frigida and Stipa grandis; and 1.8-4.0SUha(-1) for the eastern higher-rainfall Leymus chinensis meadow steppe in Hulunbeir. In the Qinghai-Tibetan alpine meadows, the stocking rate of grassland dominated by Edelweiss-Potentilla and Kobresia parva, proposed on the basis of research, was 1.0-5.8SUha(-1). In Xinjiang's desert steppe, the stocking rates of Seriphidium transiliense desert steppe were proposed on the basis of research were 1.2SUha(-1) in spring and 1.8SUha(-1) in autumn for non-degraded pasture, and 0.3 and 1.2SUha(-1) for moderate-degraded pasture, respectively. These stocking rates were based on either annual net primary production or desired levels of livestock production and it is argued that there is a need to develop carrying capacities based on a wider range of sustainability criteria and with the most appropriate grazing systems. C1 [Zhang, Y. J.; Zhang, X. Q.; Wang, X. Y.; Liu, N.; Kan, H. M.] China Agr Univ, Coll Anim Sci & Technol, Beijing 100193, Peoples R China. [Zhang, X. Q.] Chinese Acad Agr Sci, Grassland Res Inst, Hohhot 010010, Peoples R China. RP Zhang, YJ (通讯作者)，China Agr Univ, Coll Anim Sci & Technol, Beijing 100193, Peoples R China. EM zhangyj@cau.edu.cn TC 48 Z9 55 PY 2014 VL 36 IS 1 BP 1 EP 9 DI 10.1071/RJ13033 UT WOS:000330724900001 DA 2023-03-23 ER PT J AU Li, YY Dong, SK Wen, L Wang, XX Wu, Y AF Li, Yuan-yuan Dong, Shi-kui Wen, Lu Wang, Xue-xia Wu, Yu TI Three-Dimensional Framework of Vigor, Organization, and Resilience (VOR) for Assessing Rangeland Health: A Case Study from the Alpine Meadow of the Qinghai-Tibetan Plateau, China SO ECOHEALTH DT Article AB Rangeland health assessments play an important role in providing qualitative and quantitative data about ecosystem attributes and rangeland management. The objective of this study is to test the feasible of a modified model and visualize the health in a three-dimensional model. A modified Costanza model was employed, and eight indicators, including the biomass, biodiversity, and carrying capacity [associated with the vigor, organization, and resilience (VOR)] were applied. An entropy method was also developed to calculate the weight of each indicator, and a three-dimensional framework was applied to visualize the indicators and health index. The conceptual model was demonstrated using data from a case study on the alpine rangeland of the Qinghai-Tibetan Plateau, one of the globally important grassland biomes being severely degraded by natural and human factors. The health indices of four grassland plots at different levels of degradation were calculated using a modified approach to measuring their VOR. The results indicated that the least disturbed plot was relatively healthy compared to the other plots. In addition, the health indices presented in the three-dimensional VOR framework decreased in a consistent manner across the four plots along the disturbance gradients. Such rangeland health assessments should be integrated with management efforts to insure their long-term sustainable use. C1 [Li, Yuan-yuan; Dong, Shi-kui; Wen, Lu; Wang, Xue-xia; Wu, Yu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, 19 Xinjiekou Wai St, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 26 Z9 32 PD DEC PY 2013 VL 10 IS 4 BP 423 EP 433 DI 10.1007/s10393-013-0877-8 UT WOS:000332375100012 DA 2023-03-23 ER PT J AU Ren, GH Deng, B Shang, ZH Hou, Y Long, RJ AF Ren, G. H. Deng, B. Shang, Z. H. Hou, Y. Long, R. J. TI Plant communities and soil variations along a successional gradient in an alpine wetland on the Qinghai-Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB Wetlands provide essential ecosystem services, such as improved water quality and climate regulation; however, these ecosystems are shrinking on the landscape because of land use practices and climate change. We aimed to characterise how vegetation and soil factors change in these systems in a globally important wetland area on the Qinghai-Tibetan Plateau. Vegetation and soil samples were collected from four successional stages (wetland, swamp meadow, transitional meadow and mature meadow), and CCA was used to evaluate relationship changes between plant communities and soil properties with degradation succession. We observed that species richness significantly increased with degradation, and the herbaceous and sedge plants yielded to forb species. Soil clay, organic matter and nutrient content significantly decreased along successional age, but soil sand, bulk density, pH and electric conductivity significantly increased. Additionally, our results obviously indicated that vegetation composition variation was driven by soil features, particularly soil clay, bulk density and nutrient content in the early successional stage and soil sand and available nitrogen in the later stage. These observations indicated that alpine wetland degradation results in the variation of plant communities, which present different floristic compositions and species abundances that are highly structured by soil properties. (C) 2013 Elsevier B.V. All rights reserved. C1 [Ren, G. H.] Shanxi Agr Univ, Coll Anim Sci & Vet Med, Taigu 030801, Peoples R China. [Ren, G. H.; Deng, B.; Shang, Z. H.; Hou, Y.; Long, R. J.] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, Lanzhou 730000, Peoples R China. RP Long, RJ (通讯作者)，222 Tianshui South Rd, Lanzhou 730000, Gansu, Peoples R China. EM longrj@lzu.edu.cn TC 16 Z9 21 PD DEC PY 2013 VL 61 BP 110 EP 116 DI 10.1016/j.ecoleng.2013.09.017 PN A UT WOS:000328487200014 DA 2023-03-23 ER PT J AU Li, HX Liu, GH Fu, BJ AF Li, Huixia Liu, Guohua Fu, Bojie TI Spatial variations of rain-use efficiency along a climate gradient on the Tibetan Plateau: A satellite-based analysis SO INTERNATIONAL JOURNAL OF REMOTE SENSING DT Article AB Understanding the spatial relationship between rain-use efficiency (RUE) and climate conditions is crucial for predicting the steady-state responses of an ecosystem to climate variations. We clarified the spatial variations of RUE in different ecosystems along both mean annual precipitation (MAP) and mean annual temperature (MAT) gradients in the Three-river Headwaters Region (THR) of China. RUE displayed a unimodal pattern along a MAP gradient across different ecosystems, with a higher value in forest, shrub, and less-arid alpine meadow than in alpine steppe, alpine talus vegetation, and more-arid alpine meadow. RUE followed an increasing trend along the MAT gradient both in a given ecosystem and across various ecosystems. The varying maximum RUE (RUEmax) with temperature suggested that no common spatial RUEmax existed across different ecosystems in the driest pixels. With the mutual interference between precipitation and temperature excluded, RUE increased both with precipitation at a given temperature level and with temperature at a given precipitation level in cold and dry ecosystems, while RUE probably decreased both with precipitation at a given temperature level and with temperature at a given precipitation level in warm and humid ecosystems. Our study illuminates the response of RUE to climate variations in alpine areas based on the spatial model, aiming to improve our understanding of the interactions between vegetation and climate conditions and the potential trade-offs between the ecosystem's carbon and water. C1 [Li, Huixia] Foshan Univ, Dept Resource & Environm Sci, Foshan 528000, Peoples R China. [Li, Huixia; Liu, Guohua; Fu, Bojie] Chinese Acad Sci, State Key Lab Urban & Reg Ecol, Res Ctr Ecoenvironm Sci, Beijing 100085, Peoples R China. RP Li, HX (通讯作者)，Foshan Univ, Dept Resource & Environm Sci, Foshan 528000, Peoples R China. EM chinagirlshelly@163.com TC 9 Z9 14 PD NOV 10 PY 2013 VL 34 IS 21 BP 7487 EP 7503 DI 10.1080/01431161.2013.826839 UT WOS:000324459800004 DA 2023-03-23 ER PT J AU Cai, YJ Wang, XD Ding, WX Tian, LL Zhao, H Lu, XY AF Cai, Yanjiang Wang, Xiaodan Ding, Weixin Tian, Linlin Zhao, Hui Lu, Xuyang TI Potential short-term effects of yak and Tibetan sheep dung on greenhouse gas emissions in two alpine grassland soils under laboratory conditions SO BIOLOGY AND FERTILITY OF SOILS DT Article AB Yak and Tibetan sheep graze extensively on natural grasslands in the Qinghai-Tibetan Plateau, and large amounts of excrement are directly deposited onto alpine grasslands. However, information on greenhouse gas (GHG) emissions from this excrement is limited. This study evaluated the short-term effects of yak and Tibetan sheep dung on nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2) emissions from alpine steppe soil at a water holding capacity (WHC) of 40 or 60 % and from alpine meadow soil at a WHC of 60 or 80 % under laboratory conditions. Cumulative N2O emissions over a 15-day incubation period at low soil moisture conditions ranged from 111 to 232 mu g N2O-N kg soil(-1) in the yak dung treatments, significantly (P < 0.01) higher than that of sheep dung treatments (28.7 to 33.7 mu g N2O-N kg soil(-1)) and untreated soils (1.04-6.94 mu g N2O-N kg soil(-1)). At high soil moisture conditions, N2O emissions were higher from sheep dung than yak dung and non-treated soils. No significant difference was found between the yak dung and non-treated alpine meadow soil at 80 % WHC. Low N2O emission in the yak dung treatment from relatively wet soil was probably due to complete denitrification to N-2. Yak dung markedly (P < 0.001) increased CH4 and CO2 emissions, likely being the main source of these two gases. The addition of sheep dung markedly (P < 0.001) elevated CO2 emissions. Dung application significantly (P < 0.01) increased global warming potential, particularly for alpine steppe soil. In conclusion, our findings suggest that yak and Tibetan sheep dung deposited on alpine grassland soils may increase GHG emissions. C1 [Cai, Yanjiang; Wang, Xiaodan; Tian, Linlin; Zhao, Hui; Lu, Xuyang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. [Ding, Weixin] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Jiangsu, Peoples R China. RP Cai, YJ (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Surface Proc & Ecol Regulat, Chengdu 610041, Peoples R China. EM yanjiangcai@163.com TC 42 Z9 57 PD NOV PY 2013 VL 49 IS 8 BP 1215 EP 1226 DI 10.1007/s00374-013-0821-7 UT WOS:000326374900021 DA 2023-03-23 ER PT J AU Dong, QM Zhao, XQ Wu, GL Shi, JJ Ren, GH AF Dong, Quan-Min Zhao, Xin-Quan Wu, Gao-Lin Shi, Jian-Jun Ren, Guo-Hua TI A review of formation mechanism and restoration measures of "black-soil-type" degraded grassland in the Qinghai-Tibetan Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Review AB The aim of this paper was to review the formation mechanism and restorative measures of the black-soil-type degraded grassland ecosystem of the source area of Yangtze and Yellow Rivers, Qinghai-Tibetan Plateau. The relationship among plants, animals, soil, climate change, human activity and the black-soil-type degraded grassland was analyzed based on a review of literature and report of previous investigations conducted by the authors. Degradation of the black-soil-type grassland was caused by a set of complex factors such as altitude range, district characteristics and weather conditions, which existed for a long period of time. Livestock overgrazing and climate dryness were the dominant factors that caused the degradation of the grassland in question. In addition, damages done by rodents, especially pikas (Ochotona curzoniae), via burrowing through the turf and gnawing at herbs have sped up the formation process of the degradation of the black-soil-type grassland. Furthermore, with the inflation of the population in the last 20 years, the influence of human activity on grassland degradation cannot be neglected. Based on the different successive stages of degradation of the black-soil-type grassland ecosystem, different restorative measures were suggested. The lightly and moderately degraded grasslands should be kept away from disturbance, such as fencing closure, weeding, fertilizing, using rodenticide, decreasing stocking rate, optimizing population structure stocked and slaughter ages; whereas the artificial and semi-artificial grassland establishment required to restore ecosystems should be applied to heavily and extremely degraded grasslands. C1 [Dong, Quan-Min; Shi, Jian-Jun; Ren, Guo-Hua] Qinghai Acad Anim & Vet Sci, Key Lab Alpine Grassland Ecosyst Three River Head, Xining 810016, Qinghai, Peoples R China. [Dong, Quan-Min; Zhao, Xin-Quan] Chinese Acad Sci, Northwest Plateau Inst Biol, Xining 810003, Qinghai, Peoples R China. [Wu, Gao-Lin] Chinese Acad Sci, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Wu, Gao-Lin] Minist Water Resources, Yangling 712100, Shaanxi, Peoples R China. RP Zhao, XQ (通讯作者)，Chinese Acad Sci, Northwest Plateau Inst Biol, 59 Xiguan Dajie, Xining 810003, Qinghai, Peoples R China. EM dqm850@sina.com; xqzhao@nwipb.cas.cn; gaolinwu@gmail.com TC 88 Z9 110 PD NOV PY 2013 VL 70 IS 5 BP 2359 EP 2370 DI 10.1007/s12665-013-2338-7 UT WOS:000326046100038 DA 2023-03-23 ER PT J AU Li, YY Dong, SK Wen, L Wang, XX Wu, Y AF Li, Yuanyuan Dong, Shikui Wen, Lu Wang, Xuexia Wu, Yu TI The effects of fencing on carbon stocks in the degraded alpine grasslands of the Qinghai-Tibetan Plateau SO JOURNAL OF ENVIRONMENTAL MANAGEMENT DT Article AB Quantifying the carbon storage of grasslands under different management strategies can help us understand how this ecosystem responds to different land management practices. To assess the C cycle and the importance of soil microbial biomass carbon, we measured the levels of soil organic carbon, biomass carbon (above- and underground) and soil microbial biomass carbon in areas with different grazing intensities and different management strategy (fenced and unfenced) in the Qinghai-Tibetan Plateau. We also calculated the ratio of soil microbial biomass carbon to soil organic carbon as an indicator of the soil organic matter availability and quality. Results showed that degradation had significant effects on the soil organic carbon, biomass carbon and microbial biomass carbon (P < 0.05). However, fencing only had a significant effect on the non-degraded and moderately degraded grasslands (P < 0.05). We also found that the level of soil microbial biomass carbon was positively correlated with the biomass carbon and soil organic carbon. From our research, we concluded that the level of soil microbial biomass carbon was crucial to the C cycle in the alpine grasslands and that fencing may be an important management strategy for restoring lightly or moderately degraded grassland in the Qinghai-Tibetan Plateau. (C) 2013 Elsevier Ltd. All rights reserved. C1 [Li, Yuanyuan; Dong, Shikui; Wen, Lu; Wang, Xuexia; Wu, Yu] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14583 USA. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 55 Z9 59 PD OCT 15 PY 2013 VL 128 BP 393 EP 399 DI 10.1016/j.jenvman.2013.05.058 UT WOS:000326203400044 DA 2023-03-23 ER PT J AU Chen, H Zhu, QA Peng, CH Wu, N Wang, YF Fang, XQ Gao, YH Zhu, D Yang, G Tian, JQ Kang, XM Piao, SL Ouyang, H Xiang, WH Luo, ZB Jiang, H Song, XZ Zhang, Y Yu, GR Zhao, XQ Gong, P Yao, TD Wu, JH AF Chen, Huai Zhu, Qiuan Peng, Changhui Wu, Ning Wang, Yanfen Fang, Xiuqing Gao, Yongheng Zhu, Dan Yang, Gang Tian, Jianqing Kang, Xiaoming Piao, Shilong Ouyang, Hua Xiang, Wenhua Luo, Zhibin Jiang, Hong Song, Xingzhang Zhang, Yao Yu, Guirui Zhao, Xinquan Gong, Peng Yao, Tandong Wu, Jianghua TI The impacts of climate change and human activities on biogeochemical cycles on the Qinghai-Tibetan Plateau SO GLOBAL CHANGE BIOLOGY DT Review AB With a pace of about twice the observed rate of global warming, the temperature on the Qinghai-Tibetan Plateau (Earth's third pole') has increased by 0.2 degrees C per decade over the past 50years, which results in significant permafrost thawing and glacier retreat. Our review suggested that warming enhanced net primary production and soil respiration, decreased methane (CH4) emissions from wetlands and increased CH4 consumption of meadows, but might increase CH4 emissions from lakes. Warming-induced permafrost thawing and glaciers melting would also result in substantial emission of old carbon dioxide (CO2) and CH4. Nitrous oxide (N2O) emission was not stimulated by warming itself, but might be slightly enhanced by wetting. However, there are many uncertainties in such biogeochemical cycles under climate change. Human activities (e.g. grazing, land cover changes) further modified the biogeochemical cycles and amplified such uncertainties on the plateau. If the projected warming and wetting continues, the future biogeochemical cycles will be more complicated. So facing research in this field is an ongoing challenge of integrating field observations with process-based ecosystem models to predict the impacts of future climate change and human activities at various temporal and spatial scales. To reduce the uncertainties and to improve the precision of the predictions of the impacts of climate change and human activities on biogeochemical cycles, efforts should focus on conducting more field observation studies, integrating data within improved models, and developing new knowledge about coupling among carbon, nitrogen, and phosphorus biogeochemical cycles as well as about the role of microbes in these cycles. C1 [Chen, Huai; Wu, Ning; Zhu, Dan; Zhao, Xinquan] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Chen, Huai; Zhu, Qiuan; Peng, Changhui; Yang, Gang; Luo, Zhibin; Zhang, Yao] Northwest Agr & Forest Univ, Lab Ecol Forecasting & Global Change, Coll Forestry, Yangling 712100, Peoples R China. [Chen, Huai; Zhu, Qiuan; Wu, Ning; Wang, Yanfen; Gao, Yongheng; Zhu, Dan; Yang, Gang; Tian, Jianqing] Chinese Acad Sci, Zoige Peatland & Global Change Res Stn, Hongyuan 624400, Peoples R China. [Peng, Changhui; Fang, Xiuqing] Univ Quebec, Inst Environm Sci, Dept Biol Sci, Montreal, PQ C3H 3P8, Canada. [Wu, Ning] Int Ctr Integrated Mt Dev, Kathmandu, Nepal. [Wang, Yanfen; Kang, Xiaoming] Chinese Acad Sci, Grad Univ, Beijing 100039, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Tian, Jianqing] Chinese Acad Sci, Inst Microbiol, Beijing 100101, Peoples R China. [Piao, Shilong; Yao, Tandong] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100085, Peoples R China. [Piao, Shilong] Peking Univ, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. [Ouyang, Hua; Yu, Guirui] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Xiang, Wenhua] Cent South Univ Forestry & Technol, Res Sect Forest Ecol, Changsha 410004, Hunan, Peoples R China. [Jiang, Hong; Song, Xingzhang] Zhejiang Agr & Forestry Univ, Zhejiang Prov Key Lab Carbon Cycling & Carbon Seq, Linan 311300, Peoples R China. [Zhao, Xinquan] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Peoples R China. [Gong, Peng] Tsinghua Univ, Ctr Earth Syst Sci, Beijing 100084, Peoples R China. [Wu, Jianghua] Mem Univ Newfoundland, Corner Brook, NF A2H 5G4, Canada. RP Peng, CH (通讯作者)，Northwest Agr & Forest Univ, Lab Ecol Forecasting & Global Change, Coll Forestry, Yangling 712100, Peoples R China. EM chenhuai81@gmail.com; qiuan.zhu@gmail.com; peng.changhui@uqam.ca TC 519 Z9 582 PD OCT PY 2013 VL 19 IS 10 BP 2940 EP 2955 DI 10.1111/gcb.12277 UT WOS:000323844200003 DA 2023-03-23 ER PT J AU Li, N Wang, GX Liu, GS Lin, Y Sun, XY AF Li Na Wang Genxu Liu Guangsheng Lin Yun Sun Xiangyang TI The ecological implications of land use change in the Source Regions of the Yangtze and Yellow Rivers, China SO REGIONAL ENVIRONMENTAL CHANGE DT Article AB The alpine ecosystems in permafrost regions are extremely sensitive to climate change. The headwater regions of Yangtze River and Yellow River of the Qinghai-Tibet Plateau are on the permafrost area. Aerial photos of the Source Regions of the Yangtze and Yellow River taken in 1968 and three phases of TM images acquired from 1986, 2000, and 2008 were used to analyze the spatial alterations of the land cover and corresponding effects on the environment guided by landscape ecology theory. Firstly, land cover types were divided into three classes and 11 subclasses. Analysis results revealed the trends and magnitude of the eco-environmental changes in the regions over the past four decades and showed a continuous degradation of grasslands and the extension of desertification and salinization. Secondly, five landscape pattern indices (i.e., NP, MPS, PR, SHEI, CONTAG) commonly used in landscape ecological studies were calculated, and results showed that this region had become more centralized and diversified. Finally, the factors causing the degradation of alpine grasslands were analyzed. The regional climate exhibited a tendency toward significant warming and desiccation with the air temperature increased by 0.03 A degrees C per year and relative stable precipitation over the last 40 years. And the temperature of permafrost in 0-20 cm soil layer obviously raised by 0.2-0.3 A degrees C in the last 40 years. The combined effects of climate warming and permafrost variation were the major drivers for the changes of landscape in alpine ecosystems. C1 [Li Na] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolvement & Regulat, Chengdu 610041, Peoples R China. [Li Na; Wang Genxu; Liu Guangsheng; Lin Yun; Sun Xiangyang] Chinese Acad Sci, Northeast Inst Geog & Agroecol, Key Lab Mollisols Agroecol, Harbin 150081, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Northeast Inst Geog & Agroecol, Key Lab Mollisols Agroecol, Harbin 150081, Peoples R China. EM bluena820@163.com; wanggx@imde.ac.cn TC 8 Z9 9 PD OCT PY 2013 VL 13 IS 5 BP 1099 EP 1108 DI 10.1007/s10113-013-0419-5 UT WOS:000324823700015 DA 2023-03-23 ER PT J AU Li, YY Dong, SK Wen, L Wang, XX Wu, Y AF Li, Yuanyuan Dong, Shikui Wen, Lu Wang, Xuexia Wu, Yu TI Assessing the soil quality of alpine grasslands in the Qinghai-Tibetan Plateau using a modified soil quality index SO ENVIRONMENTAL MONITORING AND ASSESSMENT DT Article AB Soil degradation has caused various problems on the planet. Human disturbance and land use changes always negatively affect soil quality. In this study, we used a modified soil quality index (SQI) to assess soil quality under differing degrees of human disturbance and land use. The alpine grasslands were studied at different levels of degradation [i.e., severely degraded grassland, heavily degraded grassland, moderately degraded grassland, and non-degraded grassland (NDG)] in a case study conducted in Qinghai-Tibetan Plateau (QTP) to test the feasibility of using the SQI. Fifteen chemical, physical, and biological soil parameters were measured in each type of grassland. Significant variations in SQI were found across the different types of grasslands according to severity of human disturbance and changes in land use. Urease, the ratio of microbial biomass nitrogen to total nitrogen, proteinase, and soil organic carbon were found to be the most important indicators for assessing soil quality. NDG had a higher SQI than the other three types of grasslands. It was concluded that SQI is effective for assessing the soil quality of alpine grasslands in the QTP. The intensity of human disturbance had a negative effect on soil quality in the QTP. C1 [Li, Yuanyuan; Dong, Shikui; Wen, Lu; Wang, Xuexia; Wu, Yu] Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China. [Dong, Shikui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. RP Dong, SK (通讯作者)，Cornell Univ, Dept Nat Resources, Fernow Hall, Ithaca, NY 14853 USA. EM dongshikui@sina.com TC 16 Z9 24 PD OCT PY 2013 VL 185 IS 10 BP 8011 EP 8022 DI 10.1007/s10661-013-3151-1 UT WOS:000323836100006 DA 2023-03-23 ER PT J AU Wen, L Dong, SK Li, YY Sherman, R Shi, JJ Liu, DM Wang, YL Ma, YS Zhu, L AF Wen, Lu Dong, Shi Kui Li, Yuan Yuan Sherman, Ruth Shi, Jian Jun Liu, De Mei Wang, Yan Long Ma, Yu Shou Zhu, Lei TI The effects of biotic and abiotic factors on the spatial heterogeneity of alpine grassland vegetation at a small scale on the Qinghai-Tibet Plateau (QTP), China SO ENVIRONMENTAL MONITORING AND ASSESSMENT DT Article AB Understanding the complex effects of biotic and abiotic factors on the composition of vegetation is very important for developing and implementing strategies for promoting sustainable grassland development. The vegetation-disturbance-environment relationship was examined in degraded alpine grasslands in the headwater areas of three rivers on the Qinghai-Tibet Plateau in this study. The investigated hypotheses were that (1) the heterogeneity of the vegetation of the alpine grassland is due to a combination of biotic and abiotic factors and that (2) at a small scale, biotic factors are more important for the distribution of alpine vegetation. On this basis, four transects were set along altitudinal gradients from 3,770 to 3,890 m on a sunny slope, and four parallel transects were set along altitudinal gradients on a shady slope in alpine grasslands in Guoluo Prefecture of Qinghai Province, China. It was found that biological disturbances were the major forces driving the spatial heterogeneity of the alpine grassland vegetation and abiotic factors were of secondary importance. Heavy grazing and intensive rat activity resulted in increases in unpalatable and poisonous weeds and decreased fine forages in the form of sedges, forbs, and grasses in the vegetation composition. Habitat degradation associated with biological disturbances significantly affected the spatial variation of the alpine grassland vegetation, i.e., more pioneer plants of poisonous or unpalatable weed species, such as Ligularia virgaurea and Euphorbia fischeriana, were found in bare patches. Environmental/abiotic factors were less important than biological disturbances in affecting the spatial distribution of the alpine grassland vegetation at a small scale. It was concluded that rat control and light grazing should be applied first in implementing restoration strategies. The primary vegetation in lightly grazed and less rat-damaged sites should be regarded as a reference for devising vegetation restoration measures in alpine pastoral regions. C1 [Wen, Lu; Dong, Shi Kui; Li, Yuan Yuan; Zhu, Lei] Beijing Normal Univ, State Key Lab Water Environm Simulat, Environm Sch, Beijing 100875, Peoples R China. [Sherman, Ruth] Cornell Univ, Dept Nat Resources, Ithaca, NY 14853 USA. [Shi, Jian Jun; Wang, Yan Long; Ma, Yu Shou] Qinghai Univ, Qinghai Acad Anim Sci & Vet Med, Xining 810003, Peoples R China. [Liu, De Mei] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, State Key Lab Water Environm Simulat, Environm Sch, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 33 Z9 39 PD OCT PY 2013 VL 185 IS 10 BP 8051 EP 8064 DI 10.1007/s10661-013-3154-y UT WOS:000323836100009 DA 2023-03-23 ER PT J AU Yang, W Zheng, Y Gao, C He, XH Ding, Q Kim, Y Rui, YC Wang, SP Guo, LD AF Yang, Wei Zheng, Yong Gao, Cheng He, Xinhua Ding, Qiong Kim, Yongchan Rui, Yichao Wang, Shiping Guo, Liang-Dong TI The Arbuscular Mycorrhizal Fungal Community Response to Warming and Grazing Differs between Soil and Roots on the Qinghai-Tibetan Plateau SO PLOS ONE DT Article AB Arbuscular mycorrhizal (AM) fungi form symbiotic associations with most plant species in terrestrial ecosystems, and are affected by environmental variations. To reveal the impact of disturbance on an AM fungal community under future global warming, we examined the abundance and community composition of AM fungi in both soil and mixed roots in an alpine meadow on the Qinghai-Tibetan Plateau, China. Warming and grazing had no significant effect on AM root colonization, spore density and extraradical hyphal density. A total of 65 operational taxonomic units (OTUs) of AM fungi were identified from soil and roots using molecular techniques. AM fungal OTU richness was higher in soil (54 OTUs) than in roots (34 OTUs), and some AM fungi that differed between soil and roots, showed significantly biased occurrence to warming or grazing. Warming and grazing did not significantly affect AM fungal OTU richness in soil, but warming with grazing significantly increased AM fungal OTU richness in roots compared to the grazing-only treatment. Non-metric multidimensional scaling analysis showed that the AM fungal community composition was significantly different between soil and roots, and was significantly affected by grazing in roots, whereas in soil it was significantly affected by warming and plant species richness. The results suggest that the AM fungal community responds differently to warming and grazing in soil compared with roots. This study provides insights into the role of AM fungi under global environmental change scenarios in alpine meadows of the Qinghai-Tibetan Plateau. C1 [Yang, Wei; Zheng, Yong; Gao, Cheng; Ding, Qiong; Kim, Yongchan; Guo, Liang-Dong] Chinese Acad Sci, Inst Microbiol, State Key Lab Mycol, Beijing, Peoples R China. [Yang, Wei; Kim, Yongchan; Rui, Yichao] Univ Chinese Acad Sci, Beijing, Peoples R China. [He, Xinhua] Univ Western Australia, Sch Plant Biol, Crawley, Australia. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, Beijing, Peoples R China. RP Guo, LD (通讯作者)，Chinese Acad Sci, Inst Microbiol, State Key Lab Mycol, Beijing, Peoples R China. EM guold@sun.im.ac.cn TC 139 Z9 158 PD SEP 26 PY 2013 VL 8 IS 9 AR e76447 DI 10.1371/journal.pone.0076447 UT WOS:000325220000067 DA 2023-03-23 ER PT J AU Fu, G Zhang, XZ Zhang, YJ Shi, PL Li, YL Zhou, YT Yang, PW Shen, ZX AF Fu, Gang Zhang, Xianzhou Zhang, Yangjian Shi, Peili Li, Yunlong Zhou, Yuting Yang, Pengwan Shen, Zhenxi TI Experimental warming does not enhance gross primary production and above-ground biomass in the alpine meadow of Tibet SO JOURNAL OF APPLIED REMOTE SENSING DT Article AB In order to understand the response of gross primary production (GPP) and above-ground biomass (AGB) to warming, a field warming experiment using open-top chambers was conducted in an alpine meadow at three elevations (i.e., 4313, 4513, and 4693 m) on the Northern Tibetan Plateau in May 2010. We calculated GPP from the moderate-resolution imaging spectroradiometer algorithm and AGB using the surface measured data in 2012. Average GPP and AGB at elevation 4313 m was significantly decreased by experimental warming, whereas the declines at elevations 4513 and 4693 m were not statistically significant across all sampling dates. The negative effects of experimental warming on GPP and AGB may be related to experimental warming-induced soil drying. The different responses of GPP and AGB to experimental warming among the three alpine meadow sites could be dependent on climate conditions. Our findings suggested that experimental warming did not enhance GPP and AGB in the alpine meadow, and its effects differed among alpine meadows on the Tibetan Plateau. (C) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. C1 [Fu, Gang; Zhang, Xianzhou; Zhang, Yangjian; Shi, Peili; Li, Yunlong; Yang, Pengwan; Shen, Zhenxi] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. [Zhou, Yuting] Univ Oklahoma, Ctr Spatial Anal, Dept Microbiol & Plant Bot, Norman, OK 73019 USA. [Li, Yunlong; Yang, Pengwan] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China. RP Fu, G (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. EM shenzx@igsnrr.ac.cn TC 60 Z9 69 PD SEP 16 PY 2013 VL 7 AR 073505 DI 10.1117/1.JRS.7.073505 UT WOS:000324368100001 DA 2023-03-23 ER PT J AU Han, QF Luo, GP Li, CF Ye, H Chen, YL AF Han, QiFei Luo, GePing Li, ChaoFan Ye, Hui Chen, YaoLiang TI Modeling grassland net primary productivity and water-use efficiency along an elevational gradient of the Northern Tianshan Mountains SO JOURNAL OF ARID LAND DT Article AB Mountainous ecosystems are considered highly sensitive and vulnerable to natural disasters and climatic changes. Therefore, quantifying the effects of elevation on grassland productivity to understand ecosystem-climate interactions is vital for mountainous ecosystems. Water-use efficiency (WUE) provides a useful index for understanding the metabolism of terrestrial ecosystems as well as for evaluating the degradation of grasslands. This paper explored net primary productivity (NPP) and WUE in grasslands along an elevational gradient ranging from 400 to 3,400 m asl in the northern Tianshan Mountains-southern Junggar Basin (TMJB), Xinjiang of China, using the Biome-BGC model. The results showed that: 1) the NPP increased by 0.05 g C/(m(2)center dot a) with every increase of 1-m elevation, reached the maximum at the mid-high elevation (1,600 m asl), and then decreased by 0.06 g C/(m(2)center dot a) per 1-m increase in elevation; 2) the grassland NPP was positively correlated with temperature in alpine meadow (AM, 2,700-3,500 m asl), mid-mountain forest meadow (MMFM, 1,650-2,700 m asl) and low-mountain dry grassland (LMDG, 650-1,650 m asl), while positive correlations were found between NPP and annual precipitation in plain desert grassland (PDG, lower than 650 m asl); 3) an increase (from 0.08 to 1.09 g C/(m(2)center dot a)) in mean NPP for the grassland in TMJB under a real climate change scenario was observed from 1959 to 2009; and 4) remarkable differences in WUE were found among different elevations. In general, WUE increased with decreasing elevation, because water availability is lower at lower elevations; however, at elevations lower than 540 m asl, we did observe a decreasing trend of WUE with decreasing elevation, which may be due to the sharp changes in canopy cover over this gradient. Our research suggests that the NPP simulated by Biome-BGC is consistent with field data, and the modeling provides an opportunity to further evaluate interactions between environmental factors and ecosystem productivity. C1 [Han, QiFei; Luo, GePing; Li, ChaoFan; Ye, Hui; Chen, YaoLiang] Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China. [Han, QiFei; Li, ChaoFan; Ye, Hui; Chen, YaoLiang] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. RP Luo, GP (通讯作者)，Chinese Acad Sci, Xinjiang Inst Ecol & Geog, State Key Lab Desert & Oasis Ecol, Urumqi 830011, Peoples R China. EM luogp@ms.xjb.ac.cn TC 18 Z9 19 PD SEP PY 2013 VL 5 IS 3 BP 354 EP 365 DI 10.1007/s40333-013-0182-y UT WOS:000321558300009 DA 2023-03-23 ER PT J AU Shang, ZH Feng, QS Wu, GL Ren, GH Long, RJ AF Shang, Z. H. Feng, Q. S. Wu, G. L. Ren, G. H. Long, R. J. TI Grasslandification has significant impacts on soil carbon, nitrogen and phosphorus of alpine wetlands on the Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB Changes in land use will alter soil profiles of wetlands under climatic change and human disturbance, especially through grasslandification. Grasslandification is the process where a wetland is drained and converted to pasture. Grasslandificationon on the Tibetan plateau has been intensive over the last 40 years, mostly from drainage by humans. However, many previous studies have generally analysed only wetland ecological processes, despite the fact that grasslandificaiton, the biggest change process on the Tibetan plateau, has resulted from social and economic stresses. The assessment of changes to the soil C, N and P by grasslandification is the key to understanding the contribution to carbon management from alpine wetlands and variation of soil nutrition. We experimentally investigated the effect of grasslandification on soil physical (water, pH and EC) and chemical profiles (C, N and P) in grasslandification-pasture plots and reference wetland plots based on previous remote sensing results of the Maqu alpine wetland on the Tibetan plateau. The grasslandification process of alpine wetlands reduced vegetation quality and increased degree of drought, especially relevant with heavy grazing of the pasture. In general, grasslandification reduced the C, N and P content of soils and increased pH and EC, all significantly associated with variation to the vegetation and soil water. Soil C has changed more than N, P with grasslandification, but the soil C: N: P ratio has been relatively stable, and grasslandification has lead the wetland to the habitat with nitrogen limited. Thus, the grasslandification process of alpine wetlands on the Tibetan plateau over the last 40 years has increased net carbon emissions from alpine wetland soil contributions to atmospheric CO2. The grasslandification of alpine wetland is a drying process and observed changes were mainly influenced by variations of soil water and nutrients. Maintaining vegetation and soil water is an important approach to mitigating soil degradation and carbon emissions from alpine wetlands. In consideration of the current social and economic status of the study site, it is difficult to return or restore the grasslandification area to the original wetland, so the better strategy is to protect the existing wetland and reduce the human disturbance. (C) 2013 Elsevier B.V. All rights reserved. C1 [Shang, Z. H.; Long, R. J.] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, State Key Lab Grassland Farming Syst, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. [Shang, Z. H.] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 10085, Peoples R China. [Feng, Q. S.] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Farming Syst, Lanzhou 730020, Peoples R China. [Wu, G. L.] Northwest A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China. [Ren, G. H.] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, State Key Lab Grassland Farming Syst, Lanzhou 730020, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, State Key Lab Grassland Farming Syst, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. EM shangzhh@lzu.edu.cn TC 34 Z9 40 PD SEP PY 2013 VL 58 BP 170 EP 179 DI 10.1016/j.ecoleng.2013.06.035 UT WOS:000323610200024 DA 2023-03-23 ER PT J AU Gao, QZ Ganjurjav Li, Y Wan, YF Zhang, WN Borjigdai, A AF Gao, Qing-zhu Ganjurjav Li, Yue Wan, Yun-fan Zhang, Wei-na Borjigdai, Almaz TI Challenges in disentangling the influence of climatic and socio-economic factors on alpine grassland ecosystems in the source area of Asian major rivers SO QUATERNARY INTERNATIONAL DT Article AB Climate change and human activities affect ecosystems simultaneously. To distinguish their respective roles, we analyzed the relative impacts of climate change and human activities on alpine grasslands in Northern Tibet, which are the source area of Asian major rivers. The changes and their causes were determined using Normalized Difference Vegetation Index (NDVI) and climatic and socio-economic factors at different intensities of human activity within sampling plots (including depopulated land without human influences) from 1981 to 2006. Mann-Kendall test (MK) was used to test the trend of NDVI change and Pearson correlation analyses was utilized in multiple regressions between NDVI and the influencing factors. Abrupt changes of NDVI occurred at different times in plots that differed in human activity. Regional climate change has produced more negative than positive changes on alpine grasslands. The alpine grasslands significantly benefited under a moderate intensity of grazing activities. With the increased human activity, negative changes in NDVI were pervasive in Northern Tibet. (C) 2013 Elsevier Ltd and INQUA. All rights reserved. C1 [Gao, Qing-zhu; Ganjurjav; Li, Yue; Wan, Yun-fan; Zhang, Wei-na] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100193, Peoples R China. [Gao, Qing-zhu; Ganjurjav; Li, Yue; Wan, Yun-fan; Zhang, Wei-na] Minist Agr, Key Lab Agroenvironm & Climate Change, Beijing, Peoples R China. [Borjigdai, Almaz] MINZU Univ China, State Nationalities Affairs Commiss, Beijing 100081, Peoples R China. [Borjigdai, Almaz] MINZU Univ China, Dept Educ Key Lab Minor Tradit Med, Beijing 100081, Peoples R China. [Borjigdai, Almaz] Minzu Univ China, Inst Chinese Minor Tradit Med, Beijing 100081, Peoples R China. RP Gao, QZ (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, 12 Zhongguancun South St, Beijing 100193, Peoples R China. EM gaoqzh@ami.ac.cn TC 19 Z9 22 PD AUG 5 PY 2013 VL 304 BP 126 EP 132 DI 10.1016/j.quaint.2013.04.022 UT WOS:000323094800014 DA 2023-03-23 ER PT J AU Brierley, G Li, XL AF Brierley, Gary Li Xi-lai TI Geomorphology and environmental management of the Yellow River source zone SO JOURNAL OF MOUNTAIN SCIENCE DT Editorial Material C1 [Brierley, Gary] Univ Auckland, Sch Environm, Auckland 1, New Zealand. [Li Xi-lai] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. RP Brierley, G (通讯作者)，Univ Auckland, Sch Environm, Private Bag 92019, Auckland 1, New Zealand. EM g.brierley@auckland.ac.nz TC 3 Z9 5 PD AUG PY 2013 VL 10 IS 4 BP 628 EP 631 DI 10.1007/s11629-013-2583-y UT WOS:000322392800012 DA 2023-03-23 ER PT J AU Li, XL Perry, LWG Brierley, G Gao, J Zhang, J Yang, YW AF Li Xi-lai Perry, L. W. George Brierley, Gary Gao, Jay Zhang Jing Yang Yuan-wu TI Restoration prospects for Heitutan degraded grassland in the Sanjiangyuan SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB In many ecosystems ungulates have coexisted with grasslands over long periods of time. However, high densities of grazing animals may change the floristic and structural characteristics of vegetation, reduce biodiversity, and increase soil erosion, potentially triggering abrupt and rapid changes in ecosystem condition. Alternate stable state theory provides a framework for understanding this type of dynamic. In the Sanjiangyuan atop the Qinghai-Tibetan plateau (QTP), grassland degradation has been accompanied by irruptions of native burrowing animals, which has accentuated the loss of ground cover. Severely degraded areas of alpine meadows are referred to as 'Heitutan'. Here, using the framework of alternate stable state theory, we describe the proximate and ultimate drivers of the formation of Heitutan on the QTP, and we assess prospects for recovery, in relation to the degree of biophysical alteration, of these alpine meadows. Effective rehabilitation measures must address the underlying causes of degradation rather than their symptoms. Heitutan degradation is not uni-causal. Rather it reflects different mechanisms operating at different spatio-temporal scales across this vast region. Underlying causes include overly aggressive exploitation of the grasslands (e.g. overgrazing), amplification of grazing and erosion damage by small mammals when outbreaks occur, and/or climate change. Given marked variability in environmental conditions and stressors, restorative efforts must vary across the region. Restoration efforts are likely to yield greatest success if moderately and severely degraded areas are targeted as the first priority in management programmes, before these areas are transformed into extreme Heitutan. C1 [Li Xi-lai; Zhang Jing; Yang Yuan-wu] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Perry, L. W. George; Brierley, Gary; Gao, Jay] Univ Auckland, Sch Environm, Auckland 1, New Zealand. [Perry, L. W. George] Univ Auckland, Sch Biol Sci, Auckland 1, New Zealand. RP Li, XL (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. EM xilai-li@163.com TC 31 Z9 39 PD AUG PY 2013 VL 10 IS 4 BP 687 EP 698 DI 10.1007/s11629-013-2557-0 UT WOS:000322392800017 DA 2023-03-23 ER PT J AU Shi, XM Li, XG Li, CT Zhao, Y Shang, ZH Ma, QF AF Shi, Xiao-Ming Li, Xiao Gang Li, Chun Tao Zhao, Yu Shang, Zhan Huan Ma, Qifu TI Grazing exclusion decreases soil organic C storage at an alpine grassland of the Qinghai-Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB Grazing exclusion has been proposed as a choice for restoring degraded grasslands on the Qinghai-Tibetan Plateau, but its effects on soil properties are not clear. The present study was designed to investigate whether various soil organic carbon (OC) and nitrogen (N) pools and enzymatic activities were changed through grazing exclusion. A paddock of grassland was fenced in May 2002 for exclusion of livestock grazing, while the surrounding grassland continued conventional grazing by yak (Bos grunniens) and sheep (Ovis aries). Eight years after grazing exclusion, besides a reduction in plant species, the root biomass and soil bulk density in the top 15-cm depth were reduced by 34% and 26%, respectively, compared to the grazed grassland. Grazing exclusion enhanced the C/N ratios of shoots and roots by 18-19%, indicating a quality reduction in the shoot and root litters compared with the non-exclusion. Grazing exclusion also lowered stocks of total soil OC and N, microbial biomass C and N, and acid-extracted carbohydrate C and soil enzymatic activities (per area) of beta-glucosidase, urase, and phosphatase in the 0-15 cm soil layer. Under grazing exclusion, less C input from the root-associated sources and possibly greater C output through heterotrophic respiration might have reduced various soil OC storages. However, a significant increase in soil mineral N pool was found under no grazing compared to grazing, possibly due to less plant N demand and uptake and change in N mineralization and/or immobilization. In conclusion, grazing exclusion is not beneficial to soil OC sequestration on the northeastern Qinghai-Tibetan Plateau. (C) 2013 Elsevier B.V. All rights reserved. C1 [Shi, Xiao-Ming; Li, Xiao Gang; Zhao, Yu; Shang, Zhan Huan] Lanzhou Univ, Sch Life Sci, Lanzhou 730000, Peoples R China. [Li, Chun Tao] Tianzhu Cty Grassland Stn, Tianzhu Cty 733200, Taiwan. [Ma, Qifu] Murdoch Univ, Sch Vet & Life Sci, Murdoch, WA 6150, Australia. RP Li, XG (通讯作者)，Lanzhou Univ, Sch Life Sci, Lanzhou 730000, Peoples R China. EM lixiaogang@lzu.edu.cn TC 99 Z9 118 PD AUG PY 2013 VL 57 BP 183 EP 187 DI 10.1016/j.ecoleng.2013.04.032 UT WOS:000323156700021 DA 2023-03-23 ER PT J AU Wen, L Dong, SK Li, YY Wang, XX Li, XY Shi, JJ Dong, QM AF Wen, Lu Dong, Shikui Li, Yuanyuan Wang, Xuexia Li, Xiaoyan Shi, Jianjun Dong, Quanmin TI The impact of land degradation on the C pools in alpine grasslands of the Qinghai-Tibet Plateau SO PLANT AND SOIL DT Article AB Aims To determine the effect of grassland degradation on the soil carbon pool in alpine grassland. Methods In this study, we calculated the carbon pool in the above-and below-ground biomass, the soil microbial biomass carbon pool, the total organic carbon pool and the soil total carbon. Results Grassland degradation has resulted in decreases in biomass and carbon content and has changed the ratio of roots to shoots. However, there was less influence of degradation on dead root biomass. There was most likely a lag effect of changes in dead root biomass following grassland degradation. In the alpine grassland ecosystem, the carbon pool in soil accounts for more than 92% of the total carbon both in vegetation and soil. The carbon in alpine grassland is stored primarily in the form of total organic carbon below-ground. As organic carbon decreases, the ratio of the microbial biomass carbon pool to the total organic carbon pool increases and then declines with increasing degradation level. Along the grassland degradation gradient, the total vegetation biomass (above-and below-ground) and the soil carbon pool (microbial biomass C, total organic C and total C) all decreased. C1 [Wen, Lu; Dong, Shikui; Li, Yuanyuan; Wang, Xuexia; Li, Xiaoyan] Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China. [Shi, Jianjun; Dong, Quanmin] Qinghai Univ, Qinghai Acad Anim Sci & Vet Med, Xining 810003, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 90 Z9 102 PD JUL PY 2013 VL 368 IS 1-2 BP 329 EP 340 DI 10.1007/s11104-012-1500-4 UT WOS:000321641700024 DA 2023-03-23 ER PT J AU Yang, ZP Gao, JX Zhao, L Xu, XL Ouyang, H AF Yang, Zhao-ping Gao, Ji-xi Zhao, Lin Xu, Xing-liang Ouyang, Hua TI Linking thaw depth with soil moisture and plant community composition: effects of permafrost degradation on alpine ecosystems on the Qinghai-Tibet Plateau SO PLANT AND SOIL DT Article AB The warming of the planet in recent decades has caused rapid, widespread permafrost degradation on the Qinghai-Tibet Plateau. These changes may significantly affect soil moisture content and nutrient supply, thereby affecting ecosystem structure and function. This study aimed to describe the dynamic changes in thaw depth, assess the relationship between thaw depth and soil moisture content, and analyze the changes in species composition and water-use efficiency in response to permafrost degradation. We surveyed species composition, thaw depth, ground temperature, soil moisture, nutrient content, and foliar stable carbon isotope compositions to gain insights into the response of alpine grassland ecosystems to permafrost degradation on the Qinghai-Tibet Plateau. Moisture content of the surface layer decreased with increasing thaw depth. The correlation between thaw depth and surface soil moisture content was strongest in June and decreased in July and August. The strongest correlation occurred at a depth of 20 cm to 30 cm. The dominant species shifted from Cyperaceae in alpine meadow to mesoxerophytes in alpine steppe before finally shifting to xerophytes in alpine desert steppe. Thaw depth correlation was significantly negative with organic C content (r = -0.49, P < 0.05) and with total N content (r = -0.62, P < 0.01). The leaf delta C-13 of Carex moorcroftii increased with increasing thaw depth and followed a linear relationship (R (2) = 0.85, P = 0.008). Permafrost degradation decreases surface soil moisture and soil nutrient supply capacity. Increasing permafrost degradation decreases the number of plant families and species, with hygrophytes and mesophytes gradually replaced by mesoxerophytes and xerophytes. The water-use efficiency of plants improved in response to increasing water stress as surface layers dried during permafrost degradation. Permafrost on the Qinghai-Tibetan Plateau is expected to further degrade as global warming worsens. Therefore, more attention should be dedicated to the response of alpine ecosystems during permafrost degradation. C1 [Yang, Zhao-ping; Gao, Ji-xi] Minist Environm Protect, Nanjing Inst Environm Sci, Nanjing 210042, Jiangsu, Peoples R China. [Yang, Zhao-ping; Xu, Xing-liang; Ouyang, Hua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Zhao, Lin] Chinese Acad Sci, CAREERI, Observat & Res Stn Qinghai Tibet Plateau, Lanzhou 730000, Peoples R China. RP Yang, ZP (通讯作者)，Minist Environm Protect, Nanjing Inst Environm Sci, Nanjing 210042, Jiangsu, Peoples R China. EM yangzp04@163.com TC 55 Z9 59 PD JUN PY 2013 VL 367 IS 1-2 BP 687 EP 700 DI 10.1007/s11104-012-1511-1 UT WOS:000319771700050 DA 2023-03-23 ER PT J AU Jiang, J Zong, N Song, MH Shi, PL Ma, WL Fu, G Shen, ZX Zhang, XZ Ouyang, H AF Jiang, Jing Zong, Ning Song, Minghua Shi, Peili Ma, Weiling Fu, Gang Shen, Zhenxi Zhang, Xianzhou Ouyang, Hua TI Responses of ecosystem respiration and its components to fertilization in an alpine meadow on the Tibetan Plateau SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB Nitrogen (N) deposition alters composition and productivity of plant community, plant litter quality and quantity, composition and activity of soil microbial community. All these changes would influence ecosystem and soil CO2 emissions. We established a fertilization experiment in an alpine meadow in hinterland of the Tibetan Plateau to detect the responses of ecosystem and soil respiration to fertilization and further explore forces driving changes of CO2 fluxes. The fertilization experiment was conducted in 2008, in which five treatments were manipulated, i.e. three N levels of 0, 5, 10 g N m(-2) yr(-1) (coded as Control, LN and HN, respectively), and two N levels combined with constant level of 5 g phosphorus (P) m(-2) yr(-1), respectively (coded as LN + P and HN + P. respectively). Ecosystem respiration (Rec), above-ground plant respiration (Ra), and soil respiration (Rs) were measured in growing season of 2010 the third year of the experiment. N addition alone did not affect Rec, Ra or Rs. However, combination of N and P increased Rec, Ra and Rs mainly in later period of the growing season. Similarly, N addition did not affect aboveground biomass, but combination of N and P increased aboveground biomass. Rec, Ra and Rs were positively correlated with aboveground biomass, but were not correlated with belowground biomass, indicates enhancement of aboveground biomass by nutrient enrichment could contribute a large part of variation of ecosystem and soil respiration, especially at the end of the growing season. It is suggested that apparent negative effect of soil temperature on ecosystem and soil respiration could be confounded by the effect of aboveground biomass, especially under nutrient enrichment. (C) 2013 Elsevier Masson SAS. All rights reserved. C1 [Jiang, Jing; Zong, Ning; Song, Minghua; Shi, Peili; Ma, Weiling; Fu, Gang; Shen, Zhenxi; Zhang, Xianzhou; Ouyang, Hua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China. [Jiang, Jing; Zong, Ning; Ma, Weiling; Fu, Gang] Univ Chinese Acad Sci, Beijing 100039, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, A11 Datun Rd, Beijing 100101, Peoples R China. EM shipl@igsnrr.ac.cn TC 46 Z9 56 PD MAY-JUN PY 2013 VL 56 BP 101 EP 106 DI 10.1016/j.ejsobi.2013.03.001 UT WOS:000319635300014 DA 2023-03-23 ER PT J AU Ren, GH Shang, ZH Long, RJ Hou, Y Deng, B AF Ren, Guohua Shang, Zhanhuan Long, Ruijun Hou, Yuan Deng, Bin TI The relationship of vegetation and soil differentiation during the formation of black-soil-type degraded meadows in the headwater of the Qinghai-Tibetan Plateau, China SO ENVIRONMENTAL EARTH SCIENCES DT Article AB In alpine meadow ecosystems, considerable spatial heterogeneity in forb-dominant vegetation exists as a result of severe grassland degeneration; however, there is limited quantitative information on the vegetative differences between degenerated and pristine grasslands. Therefore, a field study, which seeks to identify the edaphic factors driving the variation in plant composition and distribution, was conducted in a severely degraded alpine meadow located in the Qinghai-Tibetan Plateau, NW China. Five meadows, an original meadow and four degraded meadows, were used to determine the differentiation and relationships between the vegetation and soil of degraded alpine meadows. The dominated species of these degraded meadows are Ligularia virgaurea-Artemisia gmelinii (LA), Oxytropis ochrocephala-Leontopodium nanum (OL), Aconitum pendulum-Potentilla anserina (AP) and Stellera chamaejasme-Artemisia nanschanica (SA), respectively. The results indicate that vegetation cover, grass biomass, species number and diversity indices clearly decrease from the original to the degraded meadow. Soil water, clay and nutrient content are also reduced with grassland degradation in surface and subsoil layers. The joint study of floristic and edaphic variables confirms that the soil features, especially the bulk density, sand content, pH, salinity, N and K, mainly determine the establishment of vegetation in the severely degraded fields of this study. These results may be useful for alpine grassland ecosystem restoration and management. C1 [Ren, Guohua; Long, Ruijun] Lanzhou Univ, Sch Life Sci, Lanzhou 730000, Peoples R China. [Ren, Guohua; Shang, Zhanhuan; Long, Ruijun; Hou, Yuan; Deng, Bin] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, Lanzhou 730020, Peoples R China. RP Long, RJ (通讯作者)，Lanzhou Univ, Sch Life Sci, 222 Tianshui South Rd, Lanzhou 730000, Peoples R China. EM guohren@gmail.com; longrj@lzu.edu.cn TC 35 Z9 40 PD MAY PY 2013 VL 69 IS 1 BP 235 EP 245 DI 10.1007/s12665-012-1951-1 UT WOS:000317425200022 DA 2023-03-23 ER PT J AU Zhang, YG Lu, ZM Liu, SS Yang, YF He, ZL Ren, ZH Zhou, JH Li, DQ AF Zhang, Yuguang Lu, Zhenmei Liu, Shanshan Yang, Yunfeng He, Zhili Ren, Zuohua Zhou, Jizhong Li, Diqiang TI Geochip-based analysis of microbial communities in alpine meadow soils in the Qinghai-Tibetan plateau SO BMC MICROBIOLOGY DT Article AB Background: GeoChip 3.0, a microbial functional gene array, containing similar to 28,000 oligonucleotide probes and targeting similar to 57,000 sequences from 292 functional gene families, provided a powerful tool for researching microbial community structure in natural environments. The alpine meadow is a dominant plant community in the Qinghai-Tibetan plateau, hence it is important to profile the unique geographical flora and assess the response of the microbial communities to environmental variables. In this study, Geochip 3.0 was employed to understand the microbial functional gene diversity and structure, and metabolic potential and the major environmental factors in shaping microbial communities structure of alpine meadow soil in Qinghai-Tibetan Plateau. Results: A total of 6143 microbial functional genes involved in carbon degradation, carbon fixation, methane oxidation and production, nitrogen cycling, phosphorus utilization, sulphur cycling, organic remediation, metal resistance, energy process and other category were detected in six soil samples and high diversity was observed. Interestingly, most of the detected genes associated with carbon degradation were derived from cultivated organisms. To identify major environmental factors in shaping microbial communities, Mantel test and CCA Statistical analyses were performed. The results indicated that altitude, C/N, pH and soil organic carbon were significantly (P < 0.05) correlated with the microbial functional structure and a total of 80.97% of the variation was significantly explained by altitude, C/N and pH. The C/N contributed 38.2% to microbial functional gene variation, which is in accordance with the hierarchical clustering of overall microbial functional genes. Conclusions: High overall functional genes and phylogenetic diversity of the alpine meadow soil microbial communities existed in the Qinghai-Tibetan Plateau. Most of the genes involved in carbon degradation were derived from characterized microbial groups. Microbial composition and structures variation were significantly impacted by local environmental conditions, and soil C/N is the most important factor to impact the microbial structure in alpine meadow in Qinghai-Tibetan plateau. C1 [Zhang, Yuguang; Li, Diqiang] Chinese Acad Forestry, Inst Forestry Ecol Environm & Protect, Beijing 100091, Peoples R China. [Zhang, Yuguang; Li, Diqiang] Chinese Acad Forestry, Key Lab Forest Ecol & Environm, State Forestry Adm, Beijing 100091, Peoples R China. [Lu, Zhenmei; He, Zhili; Zhou, Jizhong] Univ Oklahoma, Inst Environm Genom, Norman, OK 73019 USA. [Lu, Zhenmei; He, Zhili; Zhou, Jizhong] Univ Oklahoma, Dept Bot & Microbiol, Norman, OK 73019 USA. [Lu, Zhenmei] Zhejiang Univ, Coll Life Sci, Hangzhou 310058, Zhejiang, Peoples R China. [Liu, Shanshan; Yang, Yunfeng; Zhou, Jizhong] Tsinghua Univ, Dept Environm Sci & Engn, Beijing 100084, Peoples R China. [Ren, Zuohua] Hunan Agr Univ, Changsha 410128, Hunan, Peoples R China. RP Li, DQ (通讯作者)，Chinese Acad Forestry, Inst Forestry Ecol Environm & Protect, Beijing 100091, Peoples R China. EM lidq@caf.ac.cn TC 23 Z9 24 PD MAR 29 PY 2013 VL 13 AR 720 DI 10.1186/1471-2180-13-720 UT WOS:000317132400001 DA 2023-03-23 ER PT J AU Wen, L Dong, SK Li, YY Li, XY Shi, JJ Wang, YL Liu, DM Ma, YS AF Wen, Lu Dong, Shikui Li, Yuanyuan Li, Xiaoyan Shi, Jianjun Wang, Yanlong Liu, Demei Ma, Yushou TI Effect of Degradation Intensity on Grassland Ecosystem Services in the Alpine Region of Qinghai-Tibetan Plateau, China SO PLOS ONE DT Article AB The deterioration of alpine grassland has great impact on ecosystem services in the alpine region of Qinghai-Tibetan Plateau. However, the effect of grassland degradation on ecosystem services and the consequence of grassland deterioration on economic loss still remains a mystery. So, in this study, we assessed four types of ecosystem services following the Millennium Ecosystem Assessment classification, along a degradation gradient. Five sites of alpine grassland at different levels of degradation were investigated in Guoluo Prefecture of Qinghai Province, China. The species composition, aboveground biomass, soil total organic carbon (TOC), and soil total nitrogen (TN) were tested to evaluate major ecological services of the alpine grassland. We estimated the value of primary production, carbon storage, nitrogen recycling, and plant diversity. The results show the ecosystem services of alpine grassland varied along the degradation gradient. The ecosystem services of degraded grassland (moderate, heavy and severe) were all significantly lower than non-degraded grassland. Interestingly, the lightly degraded grassland provided more economic benefit from carbon maintenance and nutrient sequestration compared to non-degraded. Due to the destruction of the alpine grassland, the economic loss associated with decrease of biomass in 2008 was $198/ha. Until 2008, the economic loss caused by carbon emissions and nitrogen loss on severely degraded grassland was up to $8 033/ha and $13 315/ha, respectively. Urgent actions are required to maintain or promote the ecosystem services of alpine grassland in the Qinghai-Tibetan Plateau. C1 [Wen, Lu; Dong, Shikui; Li, Yuanyuan; Li, Xiaoyan] Beijing Normal Univ, Environm Sch, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Shi, Jianjun; Wang, Yanlong; Ma, Yushou] Qinghai Univ, Qinghai Acad Anim Sci & Vet Med, Xining, Peoples R China. [Liu, Demei] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Environm Sch, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 108 Z9 117 PD MAR 4 PY 2013 VL 8 IS 3 AR e58432 DI 10.1371/journal.pone.0058432 UT WOS:000315634900086 DA 2023-03-23 ER PT J AU Shang, ZH Deng, B Ding, LM Ren, GH Xin, GS Liu, ZY Wang, YL Long, RJ AF Shang, Zhan-Huan Deng, Bin Ding, Lu-Ming Ren, Guo-Hua Xin, Guo-Sheng Liu, Zhi-Yun Wang, Yan-Long Long, Rui-Jun TI The effects of three years of fencing enclosure on soil seed banks and the relationship with above-ground vegetation of degraded alpine grasslands of the Tibetan plateau SO PLANT AND SOIL DT Article AB Fenced enclosures have become an important method for re-establishing degraded grassland on the Tibetan plateau, and examination of soil seed banks may provide useful insights to understanding the effects and mechanisms of fencing enclosure on the restoration. An investigation was conducted into the effects of enclosure for 3 years on the soil seed banks of degraded natural and sown grasslands at eight study sites. Species composition, soil seed bank density and the relationships with above-ground vegetation were analysed based on 4800 soil core samples and counting of seeds extracted from soil samples. After 3 years of fencing enclosure, soil seed banks differed between the different communities across the study sites. Species numbers and seed density in soil seed banks decreased from natural grassland to sown grassland, with most seeds occurring in the upper 5 cm soil layer. In these alpine grasslands, relatively few species produced high numbers of seeds, although their occurrence across the eight study sites was variable. Total vegetation cover increased with enclosure due to the colonization capacity of the vegetation rather than soil seed banks. This study provided evidence that soil seed banks do not play an important role in the restoration of degraded alpine grassland when using fencing enclosures. Further studies conducted over longer periods are needed to address this subject. C1 [Shang, Zhan-Huan; Deng, Bin; Liu, Zhi-Yun; Long, Rui-Jun] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, State Key Lab Grassland Farming Syst, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Gansu, Peoples R China. [Shang, Zhan-Huan] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 10085, Peoples R China. [Ding, Lu-Ming; Ren, Guo-Hua] Lanzhou Univ, Sch Life Sci, Lanzhou 730020, Gansu, Peoples R China. [Xin, Guo-Sheng] Ningxia Univ, Sch Life Sci, Yinchuan 750021, Peoples R China. [Wang, Yan-Long] Qinghai Acad Anim & Vet Sci, Inst Grassland Sci, Xining 810003, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, State Key Lab Grassland Farming Syst, Coll Pastoral Agr Sci & Technol, 768 Jiayuguan W Rd, Lanzhou 730020, Gansu, Peoples R China. EM shangzhh@lzu.edu.cn; longrj@lzu.edu.cn TC 53 Z9 69 PD MAR PY 2013 VL 364 IS 1-2 BP 229 EP 244 DI 10.1007/s11104-012-1362-9 UT WOS:000314722800020 DA 2023-03-23 ER PT J AU Yu, GR Zhu, XJ Fu, YL He, HL Wang, QF Wen, XF Li, XR Zhang, LM Zhang, L Su, W Li, SG Sun, XM Zhang, YP Zhang, JH Yan, JH Wang, HM Zhou, GS Jia, BR Xiang, WH Li, YN Zhao, L Wang, YF Shi, PL Chen, SP Xin, XP Zhao, FH Wang, YY Tong, CL AF Yu, Gui-Rui Zhu, Xian-Jin Fu, Yu-Ling He, Hong-Lin Wang, Qiu-Feng Wen, Xue-Fa Li, Xuan-Ran Zhang, Lei-Ming Zhang, Li Su, Wen Li, Sheng-Gong Sun, Xiao-Min Zhang, Yi-Ping Zhang, Jun-Hui Yan, Jun-Hua Wang, Hui-Min Zhou, Guang-Sheng Jia, Bing-Rui Xiang, Wen-Hua Li, Ying-Nian Zhao, Liang Wang, Yan-Fen Shi, Pei-Li Chen, Shi-Ping Xin, Xiao-Ping Zhao, Feng-Hua Wang, Yu-Ying Tong, Cheng-Li TI Spatial patterns and climate drivers of carbon fluxes in terrestrial ecosystems of China SO GLOBAL CHANGE BIOLOGY DT Article AB Understanding the dynamics and underlying mechanism of carbon exchange between terrestrial ecosystems and the atmosphere is one of the key issues in global change research. In this study, we quantified the carbon fluxes in different terrestrial ecosystems in China, and analyzed their spatial variation and environmental drivers based on the long-term observation data of ChinaFLUX sites and the published data from other flux sites in China. The results indicate that gross ecosystem productivity (GEP), ecosystem respiration (ER), and net ecosystem productivity (NEP) of terrestrial ecosystems in China showed a significantly latitudinal pattern, declining linearly with the increase of latitude. However, GEP, ER, and NEP did not present a clear longitudinal pattern. The carbon sink functional areas of terrestrial ecosystems in China were mainly located in the subtropical and temperate forests, coastal wetlands in eastern China, the temperate meadow steppe in the northeast China, and the alpine meadow in eastern edge of Qinghai-Tibetan Plateau. The forest ecosystems had stronger carbon sink than grassland ecosystems. The spatial patterns of GEP and ER in China were mainly determined by mean annual precipitation (MAP) and mean annual temperature (MAT), whereas the spatial variation in NEP was largely explained by MAT. The combined effects of MAT and MAP explained 79%, 62%, and 66% of the spatial variations in GEP, ER, and NEP, respectively. The GEP, ER, and NEP in different ecosystems in China exhibited positive coupling correlation in their spatial patterns. Both ER and NEP were significantly correlated with GEP, with 68% of the per-unit GEP contributed to ER and 29% to NEP. MAT and MAP affected the spatial patterns of ER and NEP mainly by their direct effects on the spatial pattern of GEP. C1 [Yu, Gui-Rui; Zhu, Xian-Jin; Fu, Yu-Ling; He, Hong-Lin; Wang, Qiu-Feng; Wen, Xue-Fa; Li, Xuan-Ran; Zhang, Lei-Ming; Zhang, Li; Su, Wen; Li, Sheng-Gong; Sun, Xiao-Min; Wang, Hui-Min; Shi, Pei-Li; Zhao, Feng-Hua] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. [Zhu, Xian-Jin; Li, Xuan-Ran; Wang, Yan-Fen] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Zhang, Yi-Ping] Chinese Acad Sci, Xishuangbanna Trop Bot Garden, Key Lab Trop Forest Ecol, Menglun 666303, Peoples R China. [Zhang, Jun-Hui] Chinese Acad Sci, Inst Appl Ecol, Shenyang 110016, Peoples R China. [Yan, Jun-Hua] Chinese Acad Sci, S China Bot Garden, Guangzhou 510650, Guangdong, Peoples R China. [Zhou, Guang-Sheng; Jia, Bing-Rui; Chen, Shi-Ping] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Xiang, Wen-Hua] Cent S Univ Forestry & Technol, Fac Life Sci & Technol, Changsha 410004, Peoples R China. [Li, Ying-Nian; Zhao, Liang] Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Peoples R China. [Xin, Xiao-Ping] Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Beijing 100081, Peoples R China. [Wang, Yu-Ying] Chinese Acad Sci, Inst Genet & Dev Biol, Ctr Agr Resources Res, Shijiazhuang 050021, Peoples R China. [Tong, Cheng-Li] Chinese Acad Sci, Inst Subtrop Agr, Changsha 410125, Hunan, Peoples R China. RP Yu, GR (通讯作者)，Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Synth Res Ctr Chinese Ecosyst Res Network, Beijing 100101, Peoples R China. EM yugr@igsnrr.ac.cn TC 221 Z9 262 PD MAR PY 2013 VL 19 IS 3 BP 798 EP 810 DI 10.1111/gcb.12079 UT WOS:000314219700012 DA 2023-03-23 ER PT J AU Dorfer, C Kuhn, P Baumann, F He, JS Scholten, T AF Doerfer, Corina Kuehn, Peter Baumann, Frank He, Jin-Sheng Scholten, Thomas TI Soil Organic Carbon Pools and Stocks in Permafrost-Affected Soils on the Tibetan Plateau SO PLOS ONE DT Article AB The Tibetan Plateau reacts particularly sensitively to possible effects of climate change. Approximately two thirds of the total area is affected by permafrost. To get a better understanding of the role of permafrost on soil organic carbon pools and stocks, investigations were carried out including both discontinuous (site Huashixia, HUA) and continuous permafrost (site Wudaoliang, WUD). Three organic carbon fractions were isolated using density separation combined with ultrasonic dispersion: the light fractions (<1.6 g cm(-3)) of free particulate organic matter (FPOM) and occluded particulate organic matter (OPOM), plus a heavy fraction (>1.6 g cm(-3)) of mineral associated organic matter (MOM). The fractions were analyzed for C, N, and their portion of organic C. FPOM contained an average SOC content of 252 g kg(-1). Higher SOC contents (320 g kg(-1)) were found in OPOM while MOM had the lowest SOC contents (29 g kg(-1)). Due to their lower density the easily decomposable fractions FPOM and OPOM contribute 27% (HUA) and 22% (WUD) to the total SOC stocks. In HUA mean SOC stocks (0-30 cm depth) account for 10.4 kg m(-2), compared to 3.4 kg m(-2) in WUD. 53% of the SOC is stored in the upper 10 cm in WUD, in HUA only 39%. Highest POM values of 36% occurred in profiles with high soil moisture content. SOC stocks, soil moisture and active layer thickness correlated strongly in discontinuous permafrost while no correlation between SOC stocks and active layer thickness and only a weak relation between soil moisture and SOC stocks could be found in continuous permafrost. Consequently, permafrost-affected soils in discontinuous permafrost environments are susceptible to soil moisture changes due to alterations in quantity and seasonal distribution of precipitation, increasing temperature and therefore evaporation. C1 [Doerfer, Corina; Kuehn, Peter; Baumann, Frank; Scholten, Thomas] Univ Tubingen, Dept Geosci Phys Geog & Soil Sci, Tubingen, Germany. [He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. RP Dorfer, C (通讯作者)，Univ Tubingen, Dept Geosci Phys Geog & Soil Sci, Tubingen, Germany. EM corina.doerfer@uni-tuebingen.de TC 51 Z9 53 PD FEB 26 PY 2013 VL 8 IS 2 AR e57024 DI 10.1371/journal.pone.0057024 UT WOS:000315561400022 DA 2023-03-23 ER PT J AU Huo, LL Chen, ZK Zou, YC Lu, XG Guo, JW Tang, XG AF Huo, Lili Chen, Zhike Zou, Yuanchun Lu, Xianguo Guo, Jiawei Tang, Xuguang TI Effect of Zoige alpine wetland degradation on the density and fractions of soil organic carbon SO ECOLOGICAL ENGINEERING DT Article AB Following the degradation succession from swamp to swampy meadow to meadow in Zoige, a swamp, swampy meadow, and meadow, which were all adjacent, were chosen as research plots. The soil organic carbon (SOC) content of 0 cm to 50 cm soil layers decreased with degradation. However, the SOC contents all decreased with soil depth before and after the degradation, degradation led to larger soil bulk density. Thus, the SOC density at 0 cm to 50 cm were 36.95% and 51.94% lower in the swamp and meadow, respectively, than that in swampy meadow. The carbon-nitrogen (C:N) ratios in the three plots were not significantly different. However, the extent of C:N ratio was more extensive in the meadow than in the swamp and swampy meadow. Dissolved organic carbon (DOC) changed in the same trend as SOC with degradation and soil depth. At 0 cm to 50 cm soil depth, the ratio of DOC to SOC was lower in the swampy meadow than in the swamp. In addition, the soil hydrological condition in the meadow was not beneficial for DOC moving down. Thus, in 0 cm to 20 cm soil layers, the ratio of DOC to SOC was higher in the meadow than in the swamp and swampy meadow. This finding was contrary to that in 20-50 cm soil layers. With the wetland degradation content of light fraction (LF) organic carbon (LFOC) decreased. The swampy meadow had the highest HOFC content, followed by the swamp, and then the meadow. The meadow had the highest C:N ratios in LF and HF in 0 cm to 50 cm soil layers, followed by swamp and then swampy meadow. The C:N ratio in LF was higher than in HF. The ratio of LFOC and HFOC to SOC in the swampy meadow was not significantly different from that of the swamp. The LFOC-to-SOC ratios of the swampy meadow and swamp were significantly higher than that of the meadow. This result is contrary to that of HFOC. With degradation, more residues of animal and plants decomposed more thoroughly. At 0 cm to 50 cm soil layers, SOC content decreased, SOC density first increased then decreased, and most SOC was stored in a more complex and stable form. After degradation, the long-term positive feedback of SOC under warming climate maybe even stronger than that before degradation, and that may promote climate change more. Then, the ecological environment in Zoige, located in high latitude and cold area which is sensitive to climate change, may be influenced more severely. (C) 2012 Elsevier BM. All rights reserved. C1 [Huo, Lili; Chen, Zhike; Zou, Yuanchun; Lu, Xianguo; Guo, Jiawei; Tang, Xuguang] Chinese Acad Sci, Northeast Inst Geog & Agr Ecol, Key Lab Wetland Ecol & Environm, Changchun 130012, Peoples R China. [Huo, Lili; Guo, Jiawei; Tang, Xuguang] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. [Chen, Zhike] Heilongjiang Agr Reclamat Survey Design & Res Ins, Haerbin 150090, Peoples R China. RP Lu, XG (通讯作者)，Chinese Acad Sci, Northeast Inst Geog & Agr Ecol, Key Lab Wetland Ecol & Environm, Changchun 130012, Peoples R China. EM luxg@neigae.ac.cn TC 75 Z9 91 PD FEB PY 2013 VL 51 BP 287 EP 295 DI 10.1016/j.ecoleng.2012.12.020 UT WOS:000316162300035 DA 2023-03-23 ER PT J AU Yang, YF Wu, LW Lin, QY Yuan, MT Xu, DP Yu, H Hu, YG Duan, JC Li, XZ He, ZL Xue, K van Nostrand, J Wang, SP Zhou, JZ AF Yang, Yunfeng Wu, Linwei Lin, Qiaoyan Yuan, Mengting Xu, Depeng Yu, Hao Hu, Yigang Duan, Jichuang Li, Xiangzhen He, Zhili Xue, Kai van Nostrand, Joy Wang, Shiping Zhou, Jizhong TI Responses of the functional structure of soil microbial community to livestock grazing in the Tibetan alpine grassland SO GLOBAL CHANGE BIOLOGY DT Article AB Microbes play key roles in various biogeochemical processes, including carbon (C) and nitrogen (N) cycling. However, changes of microbial community at the functional gene level by livestock grazing, which is a global land-use activity, remain unclear. Here we use a functional gene array, GeoChip 4.0, to examine the effects of free livestock grazing on the microbial community at an experimental site of Tibet, a region known to be very sensitive to anthropogenic perturbation and global warming. Our results showed that grazing changed microbial community functional structure, in addition to aboveground vegetation and soil geochemical properties. Further statistical tests showed that microbial community functional structures were closely correlated with environmental variables, and variations in microbial community functional structures were mainly controlled by aboveground vegetation, soil C/N ratio, and NH4+-N. In-depth examination of N cycling genes showed that abundances of N mineralization and nitrification genes were increased at grazed sites, but denitrification and N-reduction genes were decreased, suggesting that functional potentials of relevant bioprocesses were changed. Meanwhile, abundances of genes involved in methane cycling, C fixation, and degradation were decreased, which might be caused by vegetation removal and hence decrease in litter accumulation at grazed sites. In contrast, abundances of virulence, stress, and antibiotics resistance genes were increased because of the presence of livestock. In conclusion, these results indicated that soil microbial community functional structure was very sensitive to the impact of livestock grazing and revealed microbial functional potentials in regulating soil N and C cycling, supporting the necessity to include microbial components in evaluating the consequence of land-use and/or climate changes. C1 [Yang, Yunfeng; Wu, Linwei; Yuan, Mengting; Xu, Depeng; Zhou, Jizhong] Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100084, Peoples R China. [Lin, Qiaoyan; Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. [Lin, Qiaoyan; Hu, Yigang; Duan, Jichuang; Wang, Shiping] Chinese Acad Sci, NW Inst Plateau Biol, Key Lab Adapt & Evolut Plateau Biota, Xining 810008, Peoples R China. [Yu, Hao; He, Zhili; Xue, Kai; van Nostrand, Joy; Zhou, Jizhong] Univ Oklahoma, Inst Environm Genom, Norman, OK 73019 USA. [Yu, Hao; He, Zhili; Xue, Kai; van Nostrand, Joy; Zhou, Jizhong] Univ Oklahoma, Dept Bot & Microbiol, Norman, OK 73019 USA. [Yu, Hao] Harbin Inst Technol, State Key Lab Urban Water Resource & Environm, Harbin 150090, Peoples R China. [Yu, Hao] Liaoning Tech Univ, Coll Resource & Environm Engn, Buxin 123000, Liaoning, Peoples R China. [Hu, Yigang] Chinese Acad Sci Lanzhou, Shapotou Desert Expt & Res Stn, Cold & Arid Reg & Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Li, Xiangzhen] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Zhou, Jizhong] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Yang, YF (通讯作者)，Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100084, Peoples R China. EM yangyf@tsinghua.edu.cn TC 174 Z9 214 PD FEB PY 2013 VL 19 IS 2 BP 637 EP 648 DI 10.1111/gcb.12065 UT WOS:000314219200026 DA 2023-03-23 ER PT J AU Zeng, C Zhang, F Wang, QJ Chen, YY Joswiak, DR AF Zeng, Chen Zhang, Fan Wang, Quanjiu Chen, Yingying Joswiak, Daniel R. TI Impact of alpine meadow degradation on soil hydraulic properties over the Qinghai-Tibetan Plateau SO JOURNAL OF HYDROLOGY DT Article AB Alpine meadow soil is an important ecosystem component of the Qinghai-Tibetan Plateau. However, the alpine meadow soil is undergoing serious degradation mainly due to global climate change, overgrazing, human activities and rodents. In this paper, spatial sequencing was chosen over time succession sequencing to study the changes of soil hydraulic properties under different degrees of alpine meadow degradation. Soil saturated hydraulic conductivity (Ks) and Gardner alpha both at the surface and at 40-50 cm depth were investigated in the field using tension infiltrometers. Soil physical and chemical properties, together with the root index at 0-10 cm and 40-50 cm soil layer depths were also analyzed. Pearson correlations were adopted to study the relationships among the investigated factors and principal component analysis was performed to identify the dominant factor. Results show that with increasing degree of degradation, soil sand content increased while soil Ks and Gardner alpha as well as soil clay content, soil porosity decreased in the 0-10 cm soil layers, and organic matter and root gravimetric density decreased in both the 0-10 cm and 40-50 cm soil layers. However, soil moisture showed no significant changes with increasing degradation. With decreasing pressure head, soil unsaturated hydraulic conductivity reduced more slowly under degraded conditions than non-degraded conditions. Soil Ks and Gardner alpha were significantly correlated (P = 0.01) with bulk density, soil porosity, soil organic matter and root gravimetric density. Among these, soil porosity is the dominant factor explaining about 90% of the variability in total infiltration flow. Under non-degraded conditions, the infiltration flow principally depended on the presence of macropores. With increasing degree of degradation, soil macropores quickly changed to mesopores or micropores. The proportion of total infiltration flow through macropores and mesopores significantly decreased with the most substantial decrease observed for the macropores in the 0-10 cm soil layer. The substantial decrease of macropores caused a cut in soil moisture and hydraulic conductivity. This study improves the understanding and prediction of alpine meadow soil and ecosystem changes and provides guidelines for improving water flow modeling under the background of global climate change over the Qinghai-Tibetan Plateau and similar regions. (C) 2012 Elsevier B.V. All rights reserved. C1 [Zeng, Chen; Zhang, Fan; Chen, Yingying; Joswiak, Daniel R.] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 10085, Peoples R China. [Zeng, Chen; Zhang, Fan] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol & Biodivers, Beijing 100085, Peoples R China. [Zeng, Chen; Wang, Quanjiu] Chinese Acad Sci, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China. [Wang, Quanjiu] Xian Univ Technol, Inst Water Resources, Xian 710048, Peoples R China. RP Zeng, C (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 10085, Peoples R China. EM zengchen@itpcas.ac.cn TC 72 Z9 82 PD JAN 25 PY 2013 VL 478 BP 148 EP 156 DI 10.1016/j.jhydrol.2012.11.058 UT WOS:000315612700012 DA 2023-03-23 ER PT J AU Ding, MJ Zhang, YL Sun, XM Liu, LS Wang, ZF Bai, WQ AF Ding MingJun Zhang YiLi Sun XiaoMin Liu LinShan Wang ZhaoFeng Bai WanQi TI Spatiotemporal variation in alpine grassland phenology in the Qinghai-Tibetan Plateau from 1999 to 2009 SO CHINESE SCIENCE BULLETIN DT Article AB Plant phenology is the most salient and sensitive indicator of terrestrial ecosystem response to climate change. Studying its change is significantly important in understanding and predicting impressively changes in terrestrial ecosystem. Based on NDVI from SPOT VGT, this paper analyzed the spatiotemporal changes in alpine grassland phenology in Qinghai-Tibetan Plateau from 1999 to 2009. The results are enumerated as follows: (1) The spatial distribution of the average alpine grassland phenology from 1999 to 2009 is closely related to water and heat conditions. Accompanying the deterioration in heat and water conditions from southeast to northwest, the start of growth season (SOG) was delayed gradually, the end of growth season (EOG) advanced slowly, and the length of growth season (LOG) shortened gradually. Elevation played an important role in the regional differentiation of phenology, but a dividing line of approximately 3500 m existed. Below this line, the phenology fluctuated irregularly with altitude change, whereas above the line, the phenology is closely related to altitude change. (2) From 1999 to 2009, SOG of the alpine grassland came earlier by six days per decade (R (2)=0.281, P=0.093), EOG was late by two days per decade (R (2)=0.031, P=0.605), and LOG lengthened by eight days per decade (R (2)=0.479, P=0.018). The early SOG, the late EOG, and the extended LOG mainly occurred at the center and east of the Plateau. SOG in most of the Plateau advanced significantly, especially in the eastern Plateau. (3) The inter-annual phenology changes of the alpine grassland in the Qinghai-Tibetan Plateau exhibited significant differentiation at different elevation and natural zones. The inter-annual changes at high altitude were more complicated than that at low altitude. The most significant phenology changes were found in the eastern Qinghai-Qilian montane steppe zone, and non-significant changes occurred in the Southern Tibet montane shrub-steppe zone. C1 [Ding MingJun] Jiangxi Normal Univ, Key Lab Poyang Lake Wetland & Watershed Res, Nanchang 330022, Peoples R China. [Ding MingJun; Zhang YiLi; Sun XiaoMin; Liu LinShan; Wang ZhaoFeng; Bai WanQi] Chinese Acad Sci, Inst Geog Sci & Nat Resource Res, Beijing 100101, Peoples R China. RP Zhang, YL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resource Res, Beijing 100101, Peoples R China. EM zhangyl@igsnrr.ac.cn TC 115 Z9 182 PD JAN PY 2013 VL 58 IS 3 BP 396 EP 405 DI 10.1007/s11434-012-5407-5 UT WOS:000313962600012 DA 2023-03-23 ER PT J AU Dorji, T Totland, O Moe, SR AF Dorji, Tsechoe Totland, Orjan Moe, Stein R. TI Are Droppings, Distance From Pastoralist Camps, and Pika Burrows Good Proxies for Local Grazing Pressure? SO RANGELAND ECOLOGY & MANAGEMENT DT Article AB Grazing is regarded as one of the most important factors influencing rangeland ecosystems. Many previous studies have used indirect measures (proxies) of grazing intensity, such as the distance from congregation areas and the number of herbivore excreta, to estimate effects of grazing on vegetation parameters in rangeland ecosystems. However, little is known about how such proxies reflect the true grazing intensity, and if their suitability is consistent across landscape conditions. We measured grazing intensity based on the amount of plant ramets being grazed in 75 plots positioned across a rangeland landscape in central Tibet. Several grazing intensity proxies (distance from pastoral camp sites, number of yak dung patches (old and fresh), sheep and goat dropping piles, and pika (Ochotona curzoniae) burrows (active and abandoned)) were also measured in each plot. Regression models were used to examine the suitability of these proxies in predicting our measure of real grazing intensity. None of the examined proxies satisfactorily predicted real grazing intensity in our study system. The distance from camp sites was the best proxy for grazing intensity (P < 0.001), but it explained only 30% of its variation. Fresh yak dung and active pika burrows explained only 10% and 3% of the variation in grazing intensity, respectively. The suitability of using proxies for grazing intensity did not significantly differ along landscape parameters (elevation, aspect directions, and slope angle) (P > 0.05), except that the number of animal excreta and pika burrows functioned better as proxies at low, compared to high, elevation (P < 0.05). Our results should be of concern since many studies use proxies to estimate effects of grazing on vegetation dynamics and ecosystem properties. We recommend awareness of potential limitations and suitability of proxies, when real grazing intensity is not measured. C1 [Dorji, Tsechoe; Totland, Orjan; Moe, Stein R.] Norwegian Univ Life Sci, Dept Ecol & Nat Resource Management, NO-1432 As, Norway. [Dorji, Tsechoe] Tibet Agr & Anim Husb Coll, Dept Plant Sci & Technol, Nyingchi 860000, Tibet Autonomou, Peoples R China. RP Dorji, T (通讯作者)，Norwegian Univ Life Sci, Dept Ecol & Nat Resource Management, POB 5003, NO-1432 As, Norway. EM tsechoedorji@gmail.com TC 19 Z9 19 PD JAN PY 2013 VL 66 IS 1 BP 26 EP 33 DI 10.2111/REM-D-12-00014.1 UT WOS:000314429400004 DA 2023-03-23 ER PT C AU Lehnert, LW Meyer, H Meyer, N Reudenbach, C Bendix, J AF Lehnert, Lukas W. Meyer, Hanna Meyer, Nele Reudenbach, Christoph Bendix, Joerg BE Neale, CMU Maltese, A TI Assessing pasture quality and degradation status using hyperspectral imaging: A case study from western Tibet SO REMOTE SENSING FOR AGRICULTURE, ECOSYSTEMS, AND HYDROLOGY XV SE Proceedings of SPIE DT Proceedings Paper CT Conference on Remote Sensing for Agriculture, Ecosystems, and Hydrology XV part of the 20th International Symposium on Remote Sensing CY SEP 23-26, 2013 CL Dresden, GERMANY AB Alpine grasslands on the Tibetan Plateau (TP) are suffering from pasture degradation induced by over-grazing, climate change and improper livestock management. Meanwhile, the status of pastures is largely unknown especially in poor accessible western parts on the TP. The aim of this case study was to assess the suitability of hyperspectral imaging to predict quality and amount of forage on the western TP. Therefore, 18 ground-based hyperspectral images taken along two transects on a winter pasture were used to estimate leaf chlorophyll content, photosynthetic-active vegetation cover (PV) and proportion of grasses. For calibration and validation purposes, chlorophyll content of 20 grass plants was measured in situ. From the images reference spectra of grass and non-grass species were collected. PV was assessed from similarity of images to mean vegetation spectra using spectral angle mapper and threshold classifications. A set of 48 previously published hyperspectral vegetation indices (VI) was used as predictors to estimate chlorophyll content and to discriminate grass and non-grass pixels. Separation into grass and non-grass species was performed using partial least squares (PLS) discriminant analysis and chlorophyll content was estimated with PLS regression. The accuracy of the models was assessed with leave-one-out cross validation and normalised root mean square errors (nRMSE) for chlorophyll and contingency matrices for grass classification and total PV separation. Highest error rates were observed for discrimination between vegetated and non-vegetated parts (Overall accuracy = 0.85), whilst accuracies of grass and non grass separation (Overall accuracy = 0.98) and chlorophyll estimation were higher (nRMSE = 10.7). C1 [Lehnert, Lukas W.; Meyer, Hanna; Reudenbach, Christoph; Bendix, Joerg] Univ Marburg, Fac Geog, D-35032 Marburg, Germany. RP Lehnert, LW (通讯作者)，Univ Marburg, Fac Geog, D-35032 Marburg, Germany. EM lukas.lehnert@staff.uni-marburg.de TC 4 Z9 4 PY 2013 VL 8887 AR 88870I DI 10.1117/12.2028348 UT WOS:000328503200014 DA 2023-03-23 ER PT C AU Li, CJ Wang, GX Mao, TX AF Li, Chunjie Wang, Genxu Mao, Tianxu BE Xu, QJ Ju, YH Ge, HH TI Rainfall interception by Swamp meadow and Alpine meadow and its seasonal distribution pattern on the Qinghai-Tibet Plateau, China SO PROGRESS IN ENVIRONMENTAL SCIENCE AND ENGINEERING, PTS 1-4 SE Advanced Materials Research DT Proceedings Paper CT 2nd International Conference on Energy, Environment and Sustainable Development (EESD 2012) CY OCT 12-14, 2012 CL Jilin, PEOPLES R CHINA AB In order to investigate to quantify losses by Alpine vegetation in Qinghai-Tibet Plateau, typical Swamp meadow and Alpine meadow were investigated in the growth period. The intercepting rainfall of Swamp meadow and Alpine meadow were studied by using water balance method and ANOVA statistical analysis method. The experimental results indicate that: under different coverage of Swamp meadow and Alpine meadow, rainfall interception in the growing period (June-September) both show an increasing trend. And, both the maximum rainfall interception and maximum interception rate emerge in September under different vegetation cover of Swamp meadow and Alpine meadow. However, With vegetation degeneration, interception quantity and interception rate of Swamp meadows and Alpine meadows both show decreasd trends. Interception amount and interception rate show decreased tend along with the degradation of Swamp meadow and Alpine meadow, which indicate that the degradation of meadow is unfavorable for Swamp meadow and Alpine meadow to prevent the rain landing the earth directly. C1 [Li, Chunjie; Wang, Genxu; Mao, Tianxu] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. RP Li, CJ (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM lichunjie@imde.ac.cn; wanggx@imde.ac.cn; maotianxu0214@163.com TC 0 Z9 0 PY 2013 VL 610-613 BP 2675 EP 2682 DI 10.4028/www.scientific.net/AMR.610-613.2675 PN 1-4 UT WOS:000319792101154 DA 2023-03-23 ER PT C AU Li, XL Perry, GLW Brierley, GJ Gao, J Zhang, J AF Li, Xilai Perry, George L. W. Brierley, Gary J. Gao, Jay Zhang, Jing BE Zhaoyin, W Lee, JHW Jizhang, G Shuyou, C TI Spatially Explicit Modelling Approach on the Population Dynamics of FourPlant-functional Types in Alpine Meadow, Sanjiangyuan Region, China SO PROCEEDINGS OF THE 35TH IAHR WORLD CONGRESS, VOLS III AND IV DT Proceedings Paper CT 35th World Congress of the International-Association-for-Hydro-Environment-Engineering-and-Research (IAHR) CY SEP 08-13, 2013 CL Int Assoc Hydro Environm Engn & Res, Chengdu, PEOPLES R CHINA HO Int Assoc Hydro Environm Engn & Res AB Overgrazing, along with small mammal outbreaks, has been considered a primary reason for the increased degradation of alpine meadows in the Sanjiangyuan region on the Qinghai-Tibetan Plateau (QTP). Plant-functional type (PFT) communities have been dramatically affected by such degradation. Field-based studies of PFT communities affected by degradation are inevitably short-term and local, and therefore struggle to reveal PFT patio-temporal dynamics during and after degradation. Such problems can, at least partly, be resolved using spatially explicit simulation modelling drawing on contemporary understanding of these ecosystems. A grid-based model was developed, based on field studies and existing literature, to assess controls upon grassland degradation and prospective restoration strategies using model experiments. In this study, the underlying modelling approach and rationale are discussed. Some issues about grid-based (discrete space) and spatially explicit models are introduced before details of the spatial and temporal scale, implementation (in Netlogo), model rules, and procedure modules are described. The key purpose of this study is to explain the nature of background information that underpins the model, and to detail the structure and process of the model and NetLogo platform. During the process of Heitutan degradation, the plant functional types (PFTs) population dynamics and their habitats have changed dramatically. Thus, the model description of spatially explicit modelling of four PFTs populations in alpine meadow as affected by human activities, such as over-grazing, is described in this paper. Five key modules related to the structure and processes of the simulation model are explored in detail. C1 [Li, Xilai; Zhang, Jing] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Perry, George L. W.] Univ Auckland, Sch Environm, Sch Biol Sci, Auckland 1, New Zealand. [Brierley, Gary J.; Gao, Jay] Univ Auckland, Sch Environm, Auckland 1, New Zealand. RP Li, XL (通讯作者)，Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. EM xilai-li@163.com; george.perry@auckland.ac.nz; g.brierley@auckland.ac.nz; jg.gao@auckland.ac.nz; qhlxl2001@163.com TC 0 Z9 0 PY 2013 BP 10491 EP 10506 UT WOS:000370410304038 DA 2023-03-23 ER PT C AU Qiao, YM Li, XL Schwendenmann, L Brierley, G Duan, ZH AF Qiao, Youming Li, Xilai Schwendenmann, Luitgard Brierley, Gary Duan, Zhonghua BE Zhaoyin, W Lee, JHW Jizhang, G Shuyou, C TI Plant Community Structure and Soil Carbon and Nitrogen Status of Degraded Alpine Meadows SO PROCEEDINGS OF THE 35TH IAHR WORLD CONGRESS, VOLS III AND IV DT Proceedings Paper CT 35th World Congress of the International-Association-for-Hydro-Environment-Engineering-and-Research (IAHR) CY SEP 08-13, 2013 CL Int Assoc Hydro Environm Engn & Res, Chengdu, PEOPLES R CHINA HO Int Assoc Hydro Environm Engn & Res AB This study investigates the plant community structure and soil carbon and nutrient content in Kobresia meadows atop the Qinghai-Tibetan Plateau. Three degrees of degradation of native alpine meadow and a seeded (ploughed) pasture which was established on a heavily degraded meadow were studied using standard plant ecological methods. Degradation was characterized by a shift in species composition from a Kobresia-dominated to a forb-dominated community. Live vegetation covers was reduced by 40% and vegetation height by 80% from a lightly degraded meadow to a heavily degraded meadow. The total aboveground phytomass in the three communities were similar (P>0.05), but aboveground phytomass of sedges, graminoides, and forbs was different among lightly, moderately and heavily degraded meadows (P<0.01). The Shannon's diversity index, species evenness and species richness all decreased with increasing degradation (P<0.01). Significant positive correlations were found between meadow quality cover index and diversity indices. Organic carbon (C) and total nitrogen (N) concentrations in the topsoil (0-10 cm) of lightly degraded meadows were higher (P>0.05) compared to the other meadow types. At 10-20 cm, C and N concentration and soil C stocks in the seeded pasture were significantly lower than in the other meadow types. Total carbon stocks (0-30 cm) were lowest in the seeded pasture most likely as a result of ploughing. In light of these findings, ploughing is not a recommended treatment for meadow rehabilitation. C1 [Qiao, Youming; Duan, Zhonghua] Qinghai Univ, Xining 810016, Peoples R China. [Li, Xilai] Qinghai Univ, Coll Agr & Anim Husb, Xining 810016, Peoples R China. [Schwendenmann, Luitgard; Brierley, Gary] Univ Auckland, Sch Environm, Auckland 1142, New Zealand. RP Qiao, YM (通讯作者)，Qinghai Univ, Xining 810016, Peoples R China. EM ymqiao@aliyun.com; xilai-li@163.com; l.schwendenmann@auckland.ac.nz; g.brierley@auckland.ac.nz; zhonghua.duan@yahoo.com.cn TC 0 Z9 0 PY 2013 BP 10479 EP 10490 UT WOS:000370410304037 DA 2023-03-23 ER PT J AU Qin, Y Yi, SH AF Qin, Yu Yi, Shuhua TI Diurnal Characteristics of Ecosystem Respiration of Alpine Meadow on the Qinghai-Tibetan Plateau: Implications for Carbon Budget Estimation SO SCIENTIFIC WORLD JOURNAL DT Article AB Accurately estimating daily mean ecosystem respiration rate (Re) is important for understanding how ecosystem carbon budgets will respond to climate change. Usually, daily mean Re is represented by measurement using static chamber on alpine meadow ecosystems from 9:00 to 11:00 h a.m. local time directly. In the present study, however, we found that the calculated daily mean Re from 9:00 to 11:00 h a.m. local time was significantly higher than that from 0:00 to 23:30 h local time in an alpine meadow site, which might be caused by special climate condition on the Qinghai-Tibetan Plateau. Our results indicated that the calculated daily mean Re from 9:00 to 11:00 h a.m. local time cannot be used to represent daily mean Re directly. C1 [Qin, Yu; Yi, Shuhua] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China. RP Yi, SH (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, 320 Donggang West Rd, Lanzhou 730000, Peoples R China. EM yis@lzb.ac.cn TC 6 Z9 7 PY 2013 AR 289754 DI 10.1155/2013/289754 UT WOS:000321640700001 DA 2023-03-23 ER PT J AU Shang, ZH Yang, SH Shi, JJ Wang, YL Long, RJ AF Shang, Zhan-Huan Yang, Shi-Hai Shi, Jian-Jun Wang, Yan-Long Long, Rui-Jun TI Seed rain and its relationship with above-ground vegetation of degraded Kobresia meadows SO JOURNAL OF PLANT RESEARCH DT Article AB Seed rain is a crucial element in vegetation regeneration, but has been rarely studied in high altitude regions, particularly degraded Kobresia meadow. Weed infestation is a distinctive feature of pasture degradation in Kobresia meadows on the Tibetan plateau, the ecological mechanism of which is closely related with vegetation's seed rain. In this paper we assess the effect of vegetation degradation on seed rain and consider its implication for restoration of degraded Kobresia meadows in the headwater area of Yellow river, through analysis of seed species composition, number of seeds landing per m(2) of soil surface, and their relationship with above ground vegetation. Vegetation degradation had an impact on the species composition and numbers of seeds in seed rain and their relationship with above-ground vegetation. Within the un-degraded meadow, which provided a closed vegetation cover, 35 % of the seed rain was of sedge and gramineae species. However, within the degraded meadows, as the extent of degradation increased, so the total number of seeds m(-2) increased, with those derived from sedge and gramineae species forming a declining proportion of the total. Degradation of Kobresia meadow on the Tibetan plateau is exacerbated by the seed input of weed species (such as Oxytropis ochrocephala, Carum carvi, Aconitum pendulum, Pedicularis kansuensis in this study). Therefore, a major priority for the restoration of such degraded meadows should be the elimination of these weeds from the above ground vegetation by human intervention. C1 [Shang, Zhan-Huan; Long, Rui-Jun] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Farming Syst, Lanzhou 730020, Gansu, Peoples R China. [Shang, Zhan-Huan; Yang, Shi-Hai] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100101, Peoples R China. [Shi, Jian-Jun; Wang, Yan-Long] Qinghai Acad Anim & Vet Sci, Inst Grassland Sci, Xining 810003, Peoples R China. RP Shang, ZH (通讯作者)，Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, Coll Pastoral Agr Sci & Technol, State Key Lab Grassland Farming Syst, 768 Jiayuguan W Rd, Lanzhou 730020, Gansu, Peoples R China. EM shangzhh@lzu.edu.cn; Shihai_Yang@yahoo.com.cn; shjj0318@163.com; wangyanlong506@yahoo.cn; longrj@lzu.edu.cn TC 16 Z9 25 PD JAN PY 2013 VL 126 IS 1 BP 63 EP 72 DI 10.1007/s10265-012-0498-2 UT WOS:000312783200007 DA 2023-03-23 ER PT J AU Wen, L Dong, SK Li, YY Pulver, C Li, XY Shi, JJ Wang, YL Ma, YS Liu, DM AF Wen, L. Dong, S. K. Li, Y. Y. Pulver, C. Li, X. Y. Shi, J. J. Wang, Y. L. Ma, Y. S. Liu, D. M. TI Variation of botanical composition, forage production and nutrient values along a grassland degradation gradient in the alpine region of Qinghai-Tibet Plateau SO PHYTON-INTERNATIONAL JOURNAL OF EXPERIMENTAL BOTANY DT Article AB The alpine grassland in the Qinghai-Tibet Plateau is an extensive rangeland ecosystem sustaining a sparse population of traditional nomadic pastoralists in China. However, global climate change and anthropologic disturbances have severely degraded the alpine grasslands, and the consequences of this degradation are largely unknown. Forage is the only food source for livestock in the alpine region, and livestock is the major income source for nomadic herders. Therefore, it is critical to assess the forage quantity and quality along the current grassland degradation gradient. In this study, we examined the botanical composition, biomass of different functional groups, and forage grass nutritive values, and classified forage grasses according to their biological condition: lightly degraded, moderately degraded, heavily degraded and severely degraded grasslands. A sharp reduction in vegetative production and variations in botanical composition, plant coverage and nutritive values were associated with increasing degrees of degradation of the alpine grassland. Changes in botanical composition resulted in lower nutritive values in more than in less degraded alpine forage grasses. Given the productive importance of the alpine grassland, urgent action is extremely essential to protect it from degradation. C1 [Wen, L.; Dong, S. K.; Li, Y. Y.; Li, X. Y.] Beijing Normal Univ, State Key Lab Water Environm Simulat, Sch Environm, Beijing 100875, Peoples R China. [Pulver, C.] Cornell Univ, Dept Crop & Soil Sci, Ithaca, NY 14853 USA. [Shi, J. J.; Wang, Y. L.; Ma, Y. S.] Qinghai Univ, Qinghai Acad Anim Sci & Vet Med, Xining 810003, Peoples R China. [Liu, D. M.] Chinese Acad Sci, Northwest Inst Plateau Biol, Xining 810008, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, 19 Xinjiekouwai St, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 3 Z9 4 PY 2013 VL 82 BP 45 EP 54 UT WOS:000331502800004 DA 2023-03-23 ER PT J AU Zong, N Shi, PL Jiang, J Song, MH Xiong, DP Ma, WL Fu, G Zhang, XZ Shen, ZX AF Zong, Ning Shi, Peili Jiang, Jing Song, Minghua Xiong, Dingpeng Ma, Weiling Fu, Gang Zhang, Xianzhou Shen, Zhenxi TI Responses of Ecosystem CO2 Fluxes to Short-Term Experimental Warming and Nitrogen Enrichment in an Alpine Meadow, Northern Tibet Plateau SO SCIENTIFIC WORLD JOURNAL DT Article AB Over the past decades, the Tibetan Plateau has experienced pronounced warming, yet the extent to which warming will affect alpine ecosystems depends on how warming interacts with other influential global change factors, such as nitrogen (N) deposition. A long-term warming and N manipulation experiment was established to investigate the interactive effects of warming and N deposition on alpine meadow. Open-top chambers were used to simulate warming. N addition, warming, N addition x warming, and a control were set up. In OTCs, daytime air and soil temperature were warmed by 2.0 degrees C and 1.6 degrees C above ambient conditions, but soil moisture was decreased by 4.95 m(3) m(-3). N addition enhanced ecosystem respiration (Reco); nevertheless, warming significantly decreased Reco. The decline of Reco resulting from warming was cancelled out by N addition in late growing season. Our results suggested that N addition enhanced Reco by increasing soil N availability and plant production, whereas warming decreased Reco through lowering soil moisture, soil N supply potential, and suppression of plant activity. Furthermore, season-specific responses of Reco indicated that warming and N deposition caused by future global change may have complicated influence on carbon cycles in alpine ecosystems. C1 [Zong, Ning; Shi, Peili; Xiong, Dingpeng; Ma, Weiling; Fu, Gang; Zhang, Xianzhou; Shen, Zhenxi] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Natl Ecol Res Stn, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Zong, Ning; Jiang, Jing; Xiong, Dingpeng; Ma, Weiling] Univ Chinese Acad Sci, Beijing 100049, Peoples R China. [Jiang, Jing; Song, Minghua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. RP Shi, PL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Lhasa Natl Ecol Res Stn, Key Lab Ecosyst Network Observat & Modelling, A11 Datun Rd, Beijing 100101, Peoples R China. EM shipl@igsnrr.ac.cn TC 20 Z9 25 PY 2013 AR 415318 DI 10.1155/2013/415318 UT WOS:000329661800001 DA 2023-03-23 ER PT J AU Fu, LT Bo, TL Du, GZ Zheng, XJ AF Fu, Lintao Bo, Tianli Du, Guozhen Zheng, Xiaojing TI Modeling the responses of grassland vegetation coverage to grazing disturbance in an alpine meadow SO ECOLOGICAL MODELLING DT Article AB Vegetation coverage plays an important role in hindering the erosion in grassland. The grasslands around the world are suffering from the overgrazing which usually causes coverage decrease. Thus, an urgent objective of ecology is to understand how the vegetation coverage varies with overgrazing in the grassland. Although overgrazing has been studied for a long time, its influence on the change of coverage is not well understood. This work modified Noy-Meir's model of stability in grazing systems by modeling vegetation coverage instead of biomass. The grassland of Maqu (Gansu, China), which is located on the eastern Tibetan Plateau, was chosen as the case study site. The modified model and the introduced parameters were tested, and the relationship between coverage change and the overgrazing sheep units was discussed. The modified model proved to be more suitable to describe the change of vegetation coverage under overgrazing than the published classic models. The results reveal the variation of coverage is determined corporately by grazing intensity, natural conditions and property of grassland. Besides, these results give a reasonable explanation on the difference of coverage change under various grazing situations in previous works. Moreover, the spatial and temporal heterogeneity were studied through introducing some parameters, i.e., the ideally discontinuous grazing period, the proportion that the time of overgrazing occupies in the period, homogeneous factor and restraining constant. Also, the potential positive impact of grazing on the change of coverage was discussed through increasing the growth rate, based on its role in nutrient deposition. (C) 2012 Elsevier B.V. All rights reserved. C1 [Zheng, Xiaojing] Lanzhou Univ, Dept Mech, Key Lab Mech Environm & Disaster Western China, Minist Educ,Sch Civil Engn & Mech, Lanzhou 730000, Gansu, Peoples R China. [Du, Guozhen] Lanzhou Univ, Sch Life Sci, MOE Key Lab Arid & Grassland Ecol, Lanzhou 730000, Gansu, Peoples R China. RP Zheng, XJ (通讯作者)，Lanzhou Univ, Dept Mech, Key Lab Mech Environm & Disaster Western China, Minist Educ,Sch Civil Engn & Mech, Tianshuinanlu 222, Lanzhou 730000, Gansu, Peoples R China. EM xjzheng@lzu.edu.cn TC 11 Z9 12 PD DEC PY 2012 VL 247 BP 221 EP 232 DI 10.1016/j.ecolmodel.2012.08.027 UT WOS:000313089600021 DA 2023-03-23 ER PT J AU Li, R Zhao, L Ding, YJ Wu, TH Xiao, Y Du, EJ Liu, GY Qiao, YP AF Li Ren Zhao Lin Ding YongJian Wu TongHua Xiao Yao Du ErJi Liu GuangYue Qiao YongPing TI Temporal and spatial variations of the active layer along the Qinghai-Tibet Highway in a permafrost region SO CHINESE SCIENCE BULLETIN DT Article AB Using monitored active layer thickness (ALT) and environmental variables of 10 observation fields along the Qinghai-Tibet Highway in permafrost region of the Qinghai-Tibetan Plateau (QTP), a model for ALT estimation was developed. The temporal and spatial characteristics of the ALT were also analyzed. The results showed that in the past 30 years ALT in the study region increased at a rate of 1.33 cm a(-1). Temperatures at the upper limit of permafrost and at 50 cm depth, along with soil cumulative temperature at 5 cm depth also exhibited a rising trend. Soil heat flux increased at a rate of 0.1 W m(-2) a(-1). All the above changes demonstrated that the degradation of permafrost happened in the study region on the QTP. The initial thawing date of active layer was advanced, while the initial freezing date was delayed. The number of thawing days increased to a rate of 1.18 d a(-1). The variations of active layer were closely related to the permafrost type, altitude, underlying surface type and soil composition. The variations were more evident in cold permafrost region than in warm permafrost region, in high-altitude region than in low-altitude region, in alpine meadow region than in alpine steppe region; and in fine-grained soil region than in coarse-grained soil region. C1 [Li Ren; Zhao Lin; Wu TongHua; Xiao Yao; Du ErJi; Liu GuangYue; Qiao YongPing] Res Stn Cryosphere Qinghai Xizang Tibet Plateau, Lanzhou 730000, Peoples R China. [Li Ren; Zhao Lin; Ding YongJian; Wu TongHua; Xiao Yao; Du ErJi; Liu GuangYue; Qiao YongPing] State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China. [Li Ren; Zhao Lin; Ding YongJian; Wu TongHua; Xiao Yao; Du ErJi; Liu GuangYue; Qiao YongPing] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Zhao, L (通讯作者)，Res Stn Cryosphere Qinghai Xizang Tibet Plateau, Lanzhou 730000, Peoples R China. EM linzhao@lzb.ac.cn TC 98 Z9 117 PD DEC PY 2012 VL 57 IS 35 BP 4609 EP 4616 DI 10.1007/s11434-012-5323-8 UT WOS:000312275400011 DA 2023-03-23 ER PT J AU Li, YY Dong, SK Wen, L Wang, XX Wu, Y AF Li, Yuan-yuan Dong, Shi-kui Wen, Lu Wang, Xue-xia Wu, Yu TI Soil seed banks in degraded and revegetated grasslands in the alpine region of the Qinghai-Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB To assess the role of soil seed banks in restoring degraded grasslands in the alpine region of the Qinghai-Tibetan Plateau (QTP), we studied the similarity of species composition between aboveground vegetation and soil seed banks in alpine grasslands at different degradation levels and in revegetated grasslands in different years since restoration across different seasons (spring, summer and autumn). One-way analysis of variance (ANOVA) was applied to compare differences in the soil seed bank among the native grasslands in different degraded states, in the revegetated grasslands across years since restoration and seasonal changes. The Sorenson similarity index and detrended correspondence analysis (DCA) were applied to examine the similarity of species composition in the soil seed bank and aboveground vegetation. It was found that the highest and lowest soil seed density occurred in autumn (October) and summer (July), respectively. We also explored the changes about transient and persistent soil seed banks. Basically, we found that all experimental plots were inclined to choose transient seed banks rather than persistent seed banks expect for non-degraded and 5 year restoration grasslands. There were significant differences in soil seed density among the degraded grasslands and among the different aged revegetated grasslands (P < 0.05). Soil seed density increased with decreasing levels of degradation while it increased with age since restoration. We also explored the seed density among three functional groups (grasses, sedges and forbs) and found that forbs had the highest soil seed density. A low similarity of species composition between soil seed banks and aboveground vegetation in the degraded grasslands implied that the seed bank contributed little to the restoration of the aboveground vegetation in these degraded grasslands. A high similarity of species composition between soil seed banks and aboveground vegetation in the artificially restored grasslands indicated that the seed soil bank was important in maintaining the vegetation structure and cover in the established grasslands. (C) 2012 Elsevier B.V. All rights reserved. C1 [Li, Yuan-yuan; Dong, Shi-kui; Wen, Lu; Wang, Xue-xia; Wu, Yu] Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Dong, Shi-kui] Cornell Univ, Dept Nat Resources, Ithaca, NY 14583 USA. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 34 Z9 39 PD DEC PY 2012 VL 49 BP 77 EP 83 DI 10.1016/j.ecoleng.2012.08.022 UT WOS:000320931100012 DA 2023-03-23 ER PT J AU Dong, SK Wen, L Li, YY Wang, XX Zhu, L Li, XY AF Dong, S. K. Wen, L. Li, Y. Y. Wang, X. X. Zhu, L. Li, X. Y. TI Soil-Quality Effects of Grassland Degradation and Restoration on the Qinghai-Tibetan Plateau SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL DT Article AB Alpine grassland and the soil on which it is growing in the Qinghai-Tibetan Plateau (QTP) of China is being degraded in an attempt to increase food and feed production for an increasing global population. Our objective was to use soil quality assessment to quantify changes in soil chemical and physical properties at three depth increments (0 to 4, 4 to 10, and 10 to 20 cm) and thus determine the linkages between soil and vegetation changes, the soil element(s) limiting grassland restoration in alpine region, and the ability to restore soil fertility by reestablishing grasslands. The soil and vegetation were sampled in the different types of degraded grasslands, that is, moderately degraded grassland (MDG), heavily degraded grassland (HDG) and severely degraded grassland (SDG) as well as in the reestablished grasslands at different ages, that is, 5-yr restored grassland (5yRG), 7-yr restored grassland (7yRG), and 9-yr restored grassland (9yRG) for comparative study. The results show: (i) decreased water holding capacity and increased soil hardness as vegetative cover declined, (ii) decreased soil organic carbon (OC) and total nitrogen (TN) and increased total soil potassium, (TK) (iii) the establishment of artificial grassland did not restore soil quality or nutrient stocks within degraded grassland soils, and (iv) yearly variations in soil properties at different depths were significant along the degree of grassland degradation. Significant variations of soil physical and chemical parameters might be attributed to loss of the top soil and changes of vegetation composition and soil and textures. Soil quality can be used to assess grassland degradation and restoration in the alpine region. In conclusion, better soil management is needed for restoring the degraded alpine grasslands on the QTP. C1 [Dong, S. K.; Wen, L.; Li, Y. Y.; Wang, X. X.; Zhu, L.; Li, X. Y.] Beijing Normal Univ, Sch Environm, State Key Lab Water Environ Simulat, Beijing 100875, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, State Key Lab Water Environ Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 116 Z9 144 PD NOV-DEC PY 2012 VL 76 IS 6 BP 2256 EP 2264 DI 10.2136/sssaj2012.0092 UT WOS:000312180100033 DA 2023-03-23 ER PT J AU Unteregelsbacher, S Hafner, S Guggenberger, G Miehe, G Xu, XL Liu, JQ Kuzyakov, Y AF Unteregelsbacher, Sebastian Hafner, Silke Guggenberger, Georg Miehe, Georg Xu, Xingliang Liu, Jianquan Kuzyakov, Yakov TI Response of long-, medium- and short-term processes of the carbon budget to overgrazing-induced crusts in the Tibetan Plateau SO BIOGEOCHEMISTRY DT Article AB The Kobresia pastures of the Tibetan Plateau represent the world's largest alpine grassland ecosystem. These pastures remained stable during the last millennia of nomadic animal husbandry. However, strongly increased herds' density has promoted overgrazing, with unclear consequences for vegetation and soils, particularly for cycles of carbon (C), nutrients and water. Vegetation-free patches of dead root-mat covered by blue-green algae and crustose lichens (crusts) are common in overgrazed Kobresia pastures, but their effect on C turnover processes is completely unknown. We tested the hypothesis that the crusts strongly affect the C cycle by examining: (i) the long-term C stock measured as soil organic matter content; (ii) medium-term C stock as dead roots; (iii) recent C fluxes analyzed as living roots and CO2 efflux; and (iv) fast decomposition of root exudates. Up to 7.5 times less aboveground and 1.9 times less belowground living biomass were found in crust patches, reflecting a much smaller C input to soil as compared with the non-crust Kobresia patches. A lower C input initially changed the long-term C stock under crusts in the upper root-mat horizon. Linear regression between living roots and CO2 efflux showed that roots contributed 23% to total CO2 under non-crust areas (mean July-August 5.4 g C m(-2) day(-1)) and 18% under crusts (5.1 g C m(-2) day(-1)). To identify differences in the fast turnover processes in soil, we added C-13 labeled glucose, glycine and acetic acid, representing the three main groups of root exudates. The decomposition rates of glucose (0.7 day(-1)), glycine (1.5 day(-1)) and acetic acid (1.2 day(-1)) did not differ under crusts and non-crusts. More C-13, however, remained in soil under crusts, reflecting less complete decomposition of exudates and less root uptake. This shows that the crust patches decrease the rates of medium-term C turnover in response to the much lower C input. Very high C-13 amounts recovered in plants from non-crust areas as well as the two times lower uptake by roots under crusts indicate that very dense roots are efficient competitors with microorganisms for soluble organics. In conclusion, the altered C cycle in the overgrazing-induced crustose lichens and blue-green algae crusts is connected with strongly decreased C input and reduced medium-term C turnover. C1 [Unteregelsbacher, Sebastian; Kuzyakov, Yakov] Univ Bayreuth, BayCEER, Dept Agroecosyst Res, Bayreuth, Germany. [Guggenberger, Georg] Leibniz Univ Hannover, Inst Soil Sci, D-30167 Hannover, Germany. [Miehe, Georg] Univ Marburg, Fac Geog, Marburg, Germany. [Xu, Xingliang; Kuzyakov, Yakov] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Liu, Jianquan] Chinese Acad Sci, NW Inst Plateau Biol Xining, Xining, Qinghai, Peoples R China. [Kuzyakov, Yakov] Univ Gottingen, Dept Soil Sci Temperate Ecosyst, D-37077 Gottingen, Germany. RP Kuzyakov, Y (通讯作者)，Univ Gottingen, Dept Soil Sci Temperate Ecosyst, D-37077 Gottingen, Germany. EM kuzyakov@gwdg.de TC 26 Z9 28 PD NOV PY 2012 VL 111 IS 1-3 BP 187 EP 201 DI 10.1007/s10533-011-9632-9 UT WOS:000314063200012 DA 2023-03-23 ER PT J AU Wang, SP Duan, JC Xu, GP Wang, YF Zhang, ZH Rui, YC Luo, CY Xu, B Zhu, XX Chang, XF Cui, XY Niu, HS Zhao, XQ Wang, WY AF Wang, Shiping Duan, Jichuang Xu, Guangping Wang, Yanfen Zhang, Zhenhua Rui, Yichao Luo, Caiyun Xu, Burenbayin Zhu, Xiaoxue Chang, Xiaofeng Cui, Xiaoyong Niu, Haishan Zhao, Xinquan Wang, Wenying TI Effects of warming and grazing on soil N availability, species composition, and ANPP in an alpine meadow SO ECOLOGY DT Article AB Uncertainty about the effects of warming and grazing on soil nitrogen (N) availability, species composition, and aboveground net primary production (ANPP) limits our ability to predict how global carbon sequestration will vary under future warming with grazing in alpine regions. Through a controlled asymmetrical warming (1.2/1.7 degrees C during daytime/nighttime) with a grazing experiment from 2006 to 2010 in an alpine meadow, we found that warming alone and moderate grazing did not significantly affect soil net N mineralization. Although plant species richness significantly decreased by 10% due to warming after 2008, we caution that this may be due to the transient occurrence or disappearance of some rare plant species in all treatments. Warming significantly increased graminoid cover, except in 2009, and legume cover after 2008, but reduced non-legume forb cover in the community. Grazing significantly decreased cover of graminoids and legumes before 2009 but increased forb cover in 2010. Warming significantly increased ANPP regardless of grazing, whereas grazing reduced the response of ANPP to warming. N addition did not affect ANPP in both warming and grazing treatments. Our findings suggest that soil N availability does not determine ANPP under simulated warming and that heavy grazing rather than warming causes degradation of the alpine meadows. C1 [Wang, Shiping; Duan, Jichuang; Zhang, Zhenhua; Luo, Caiyun; Xu, Burenbayin; Zhu, Xiaoxue; Chang, Xiaofeng; Zhao, Xinquan] Chinese Acad Sci, NW Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Alpine Ecol & Biodivers, Beijing 100101, Peoples R China. [Wang, Shiping] Univ Tibet, Naqu Ecol & Environm Observat & Res Stn, Naqu 852000, Peoples R China. [Wang, Shiping] Chinese Acad Sci, Inst Tibetan Plateau Res, Naqu 852000, Peoples R China. [Duan, Jichuang; Wang, Yanfen; Zhang, Zhenhua; Rui, Yichao; Xu, Burenbayin; Zhu, Xiaoxue; Chang, Xiaofeng; Cui, Xiaoyong; Niu, Haishan] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. [Xu, Guangping] Guangxi Zhuangzu Autonomous Reg Chinese Acad Sci, Guangxi Inst Bot, Guangxi 541006, Peoples R China. [Wang, Wenying] Qinghai Normal Univ, Coll Life & Geog Sci, Xining 810008, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, NW Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. EM wangship2008@yahoo.cn TC 261 Z9 321 PD NOV PY 2012 VL 93 IS 11 BP 2365 EP 2376 DI 10.1890/11-1408.1 UT WOS:000310834900008 DA 2023-03-23 ER PT J AU Chen, SY Liu, WJ Qin, X Liu, YS Zhang, TZ Chen, KL Hu, FZ Ren, JW Qin, DH AF Chen, Shengyun Liu, Wenjie Qin, Xiang Liu, Yushuo Zhang, Tongzuo Chen, Kelong Hu, Fengzu Ren, Jiawen Qin, Dahe TI Response characteristics of vegetation and soil environment to permafrost degradation in the upstream regions of the Shule River Basin SO ENVIRONMENTAL RESEARCH LETTERS DT Article AB Permafrost degradation exhibits striking and profound influences on the alpine ecosystem, and response characteristics of vegetation and soil environment to such degradation inevitably differ during the entire degraded periods. However, up to now, the related research is lacking in the Qinghai-Tibetan Plateau (QTP). For this reason, twenty ecological plots in the different types of permafrost zones were selected in the upstream regions of the Shule River Basin on the northeastern margin of the QTP. Vegetation characteristics (species diversity, community coverage and biomass etc) and topsoil environment (temperature (ST), water content (SW), mechanical composition (SMC), culturable microorganism (SCM), organic carbon (SOC) and total nitrogen (TN) contents and so on), as well as active layer thickness (ALT) were investigated in late July 2009 and 2010. A spatial-temporal shifts method (the spatial pattern that is represented by different types of permafrost shifting to the temporal series that stands for different stages of permafrost degradation) has been used to discuss response characteristics of vegetation and topsoil environment throughout the entire permafrost degradation. The results showed that (1) ST of 0-40 cm depth and ALT gradually increased from highly stable and stable permafrost (H-SP) to unstable permafrost (UP). SW increased initially and then decreased, and SOC content and the quantities of SCM at a depth of 0-20 cm first decreased and then increased, whereas TN content and SMC showed obscure trends throughout the stages of permafrost degradation with a stability decline from H-SP to extremely unstable permafrost (EUP); (2) further, species diversity, community coverage and biomass first increased and then decreased in the stages from H-SP to EUP; (3) in the alpine meadow ecosystem, SOC and TN contents increased initially and then decreased, soil sandy fractions gradually increased with stages of permafrost degradation from substable (SSP) to transitional (TP), and to UP. Meanwhile, SOC/TN storages increased in the former stage, while they decreased in the latter stage. This study indicated that the response characteristics of vegetation and soil environment varied throughout the entire permafrost degradation, and SW was the dominant ecological factor that limited vegetation distribution and growth. Therefore, SSP and TP phases could provide a favourable environment for plant growth, mainly contributing to high SW. C1 [Chen, Shengyun; Liu, Wenjie; Qin, Xiang; Liu, Yushuo; Ren, Jiawen; Qin, Dahe] Chinese Acad Sci, State Key Lab Cryospher Sci, Qilian Shan Stn Glaciol & Ecol Environm, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Zhang, Tongzuo; Hu, Fengzu] Chinese Acad Sci, NW Inst Plateau Biol, Xining 810008, Peoples R China. [Chen, Kelong] Qinghai Normal Univ, Biol & Geog Sci Inst, Xining 810008, Peoples R China. RP Chen, SY (通讯作者)，Chinese Acad Sci, State Key Lab Cryospher Sci, Qilian Shan Stn Glaciol & Ecol Environm, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. EM sychen@lzb.ac.cn TC 49 Z9 53 PD OCT-DEC PY 2012 VL 7 IS 4 AR 045406 DI 10.1088/1748-9326/7/4/045406 UT WOS:000312696400059 DA 2023-03-23 ER PT J AU Fu, G Shen, ZX Zhang, XZ Zhou, YT AF Fu, Gang Shen, Zhenxi Zhang, Xianzhou Zhou, Yuting TI Response of soil microbial biomass to short-term experimental warming in alpine meadow on the Tibetan Plateau SO APPLIED SOIL ECOLOGY DT Article AB In order to understand the response of soil microbial biomass to warming, field warming experiments using open top chambers (OTCs) were conducted in three alpine meadow sites on the Northern Tibetan Plateau since May 2010. Soil samples for microbial biomass carbon (MBC) and nitrogen (MBN) measurements were collected in July, August and September 2011. Generally, experimental warming had no obvious effect on MBC. MBN and MBC/MBN ratio across the three sampling dates. However, experimental warming tended to decrease MBC and MBN but increase MBC/MBN ratio. The negative effect of experimental warming on microbial biomass may be related to warming-induced decline in soil water content. Our findings suggested that short-term experimental warming may have no obvious effect on microbial biomass for the alpine meadow on the Tibetan Plateau. (c) 2012 Elsevier B.V. All rights reserved. C1 [Fu, Gang; Shen, Zhenxi; Zhang, Xianzhou; Zhou, Yuting] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. [Fu, Gang; Zhou, Yuting] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. RP Shen, ZX (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. EM shenzx@igsnrr.ac.cn TC 56 Z9 73 PD OCT PY 2012 VL 61 SI SI BP 158 EP 160 DI 10.1016/j.apsoil.2012.05.002 UT WOS:000309789700019 DA 2023-03-23 ER PT J AU Wei, D Xu-Ri Wang, YH Wang, YS Liu, YW Yao, TD AF Wei, Da Xu-Ri Wang, Yinghong Wang, Yuesi Liu, Yongwen Yao, Tandong TI Responses of CO2, CH4 and N2O fluxes to livestock exclosure in an alpine steppe on the Tibetan Plateau, China SO PLANT AND SOIL DT Article AB Most alpine steppe grasslands on the Tibetan Plateau have in recent decades come under increasing threat from overgrazing due to population growth and food demand. Livestock exclosure has been widely employed by China's state and local authorities as a management practice aimed at restoring and protecting these fragile ecosystems. However, its effects on greenhouse gas fluxes are unclear. Therefore, measurements and analyses of key GHG fluxes (CO2, CH4 and N2O) were carried out in grazed and fenced areas of an alpine steppe grassland in the central Tibetan Plateau during the growing seasons of 2009 and 2010. Results showed that: (1) For the grazed area, ecosystem respiration was 156.1 +/- 19.6 and 92.7 +/- 11.7 mg.m(-2).h(-1), soil CH4 flux was -63.4 +/- 6.0 and -70.2 +/- 10.4 mu g.m(-2).h(-1), and soil N2O flux was 0.1 +/- 0.9 and -0.5 +/- 1.3 mu g.m(-2).h(-1) during the growing seasons of 2009 and 2010, respectively. (2) For the fenced area, ecosystem respiration was 131.5 +/- 14.3 and 114.3 +/- 10.6 mg.m(-2).h(-1), the CH4 flux rate was -84.8 +/- 7.3 and -82.7 +/- 9.2 mu g.m(-2).h(-1), and soil N2O flux was 0.7 +/- 0.5 and -5.8 +/- 2.8 mu g.m(-2).h(-1) in 2009 and 2010, respectively. (3) CO2 emission was positively correlated with soil moisture and temperature, while CH4 uptake was negatively correlated with soil moisture. The correlation between N2O flux with soil temperature or moisture was not significant. (4) Livestock exclosure decreased the Q(10) value of CO2 emission, and enhanced CH4 uptake by 17.8% and 33.8% in 2009 and 2010, respectively, while its effect on CO2 emission and N2O flux was not significant. The lower Q(10) value of CO2 emissions and higher CH4 consumption rate in the fenced area after 4 years of grazing exclusion imply that livestock exclosure might be a promising measure to reduce CO2 emission sensitivity and enhance CH4 uptake in alpine steppe grasslands. C1 [Wei, Da; Xu-Ri; Liu, Yongwen; Yao, Tandong] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100085, Peoples R China. [Wang, Yinghong; Wang, Yuesi] Chinese Acad Sci, Inst Atmospher Phys, Beijing 100085, Peoples R China. [Wei, Da; Liu, Yongwen] Chinese Acad Sci, Grad Univ, Beijing 100085, Peoples R China. RP Xu-Ri (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Shuangqing Rd 18,POB 2871, Beijing 100085, Peoples R China. EM xu-ri@itpcas.ac.cn TC 118 Z9 135 PD OCT PY 2012 VL 359 IS 1-2 BP 45 EP 55 DI 10.1007/s11104-011-1105-3 UT WOS:000308960800005 DA 2023-03-23 ER PT J AU Yu, KL Pypker, TG Keim, RF Chen, N Yang, YB Guo, SQ Li, WJ Wang, G AF Yu, Kailiang Pypker, Thomas G. Keim, Richard F. Chen, Ning Yang, Yingbo Guo, Shuqing Li, Wenjin Wang, Gang TI Canopy rainfall storage capacity as affected by sub-alpine grassland degradation in the Qinghai-Tibetan Plateau, China SO HYDROLOGICAL PROCESSES DT Article AB Grassland degradation resulting from global climate change, overgrazing, and rodent damage is expected to influence the magnitude of canopy hydrological fluxes because of reduced vegetation biomass and changed species composition. The objectives of this study were to estimate herbaceous canopy rainfall storage capacity (S) along three different stages of sub-alpine grassland degradation (non-degraded, lightly degraded and moderately degraded) in the QinghaiTibetan Plateau, China, and relate changes in S to canopy properties. An artificial wetting method and the water budget balance method, using rain simulations, were used for estimating S. Grassland degradation significantly reduced S. In non-degraded, lightly degraded and moderately degraded grasslands, S estimated using the artificial wetting method were 0.612?+/-?0.08?mm, 0.289?+/-?0.04?mm, and 0.217?+/-?0.01?mm, respectively; S estimated using the water budget balance method were 0.979?+/-?0.32?mm, 0.493?+/- 0.13?mm, and 0.419?+/-?0.09?mm, respectively. These changes could be explained by accompanying changes in above-ground biomass and leaf area index, as well as changes in species composition. Species-specific rainfall storage capacity varied by a factor of 2.7 among the investigated species, with graminoids having the lowest values. Leaf area index was more correlated to S than was canopy coverage. Converting fresh weight of non-leaf tissues into effective leaf area of the corresponding species and then introducing a coefficient of leaf area according to the specific storage capacity of leaves improved the linear relationship between S and leaf area index. Copyright (c) 2011 John Wiley & Sons, Ltd. C1 [Yu, Kailiang; Chen, Ning; Yang, Yingbo; Guo, Shuqing; Li, Wenjin; Wang, Gang] Lanzhou Univ, MOE Key Lab Arid & Grassland Ecol, Lanzhou 730000, Peoples R China. [Pypker, Thomas G.] Michigan Technol Univ, Sch Forest Resources & Environm Sci, Houghton, MI 49931 USA. [Keim, Richard F.] Louisiana State Univ, Sch Renewable Nat Resources, Ctr Agr, Baton Rouge, LA 70803 USA. RP Wang, G (通讯作者)，Lanzhou Univ, MOE Key Lab Arid & Grassland Ecol, Lanzhou 730000, Peoples R China. EM wgmg36@lzu.edu.cn TC 20 Z9 21 PD SEP 30 PY 2012 VL 26 IS 20 BP 3114 EP 3123 DI 10.1002/hyp.8377 UT WOS:000308643700012 DA 2023-03-23 ER PT J AU Wang, GX Liu, GS Li, CJ Yang, Y AF Wang Genxu Liu Guangsheng Li Chunjie Yang Yan TI The variability of soil thermal and hydrological dynamics with vegetation cover in a permafrost region SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Understanding the interaction between the soil thermal-water regime and variations in vegetation cover is a key issue in land surface research and in predicting the responses of alpine ecosystems in permafrost regions to climate changes. Alpine meadows and swamps were selected to investigate the effects of changes in the soil moisture and temperature dynamics in the active layer. The differences in soil temperature and moisture in areas with different amounts of vegetation coverage were evaluated using active layer soil water and temperature indexes from a field investigation that was conducted from the years 2005-2009. Declines in vegetation cover in alpine meadows resulted in an increase in the soil-thawing temperature and moisture, a decrease in the soil-freezing temperature and moisture, and an advance in the onset of seasonal changes in the soil temperature. Changes in the vegetation cover had distinct effects on soil thermal and water dynamics in alpine swamps and meadows. The annual variations of active soil temperature and moisture dynamics were controlled by the synergic influences of climate and vegetation cover changes. We found that as the vegetation cover decreased, the sensitivity of the soil to climate changes increased with greater shifts in the annual soil temperature and water dynamics. An empirical Boltzmann formula for the soil water-temperature relationship was identified to understand how vegetation cover inhibited or drove permafrost changes by varying the soil water-thermal coupling cycle. The results confirmed that vegetation cover was one of the most important factors that control the soil water and thermal cycles in permafrost. The degradation of vegetation could accelerate the effects of climate change on the permafrost environment. (C) 2012 Elsevier B.V. All rights reserved. C1 [Wang Genxu; Liu Guangsheng; Li Chunjie; Yang Yan] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM wanggx@imde.ac.cn TC 79 Z9 97 PD SEP 15 PY 2012 VL 162 BP 44 EP 57 DI 10.1016/j.agrformet.2012.04.006 UT WOS:000305767900005 DA 2023-03-23 ER PT J AU Fu, G Shen, ZX Zhang, XZ Zhou, YT Zhang, YJ AF Fu, Gang Shen, Zhenxi Zhang, Xianzhou Zhou, Yuting Zhang, Yangjian TI Response of microbial biomass to grazing in an alpine meadow along an elevation gradient on the Tibetan Plateau SO EUROPEAN JOURNAL OF SOIL BIOLOGY DT Article AB Although grazing is a common land use type, few studies are available about the response of soil microbial biomass to grazing especially above 4300 m on the Tibetan Plateau. Therefore, three fenced enclosures were made at three alpine meadow sites along an elevation gradient (4313 m, winter pasture; 4513 m and 4693 m, summer pasture) in July 2008. Soil samples inside and outside the fenced enclosures were gathered in July, August and September 2011. Microbial biomass C (MBC) and N (MBN) were determined using the chloroform fumigation-extraction method. Grazing marginally declined MBC by 21.60%. 4.83% and 5.36% across sampling dates at elevation 4313 m, 4513 m and 4693 m, respectively. Grazing significantly declined MBN by 39.58% and 18.88% across sampling dates at elevation 4313 m and 4693 m, respectively, whereas it slightly declined MBN by 1.50% at elevation 4513 m. Microbial biomass at elevation 4693 m was significantly higher in comparison with elevation 4513 m and 4313 m, whereas soil temperature at elevation 4693 m was 2.3 degrees C and 2.8 degrees C lower than that at elevation 4513 m and 4313 m, respectively. Our findings suggest that MBN may respond more rapidly to grazing than MBC and that climate warming and grazing may decline microbial biomass for the alpine meadow. (C) 2012 Elsevier Masson SAS. All rights reserved. C1 [Fu, Gang; Shen, Zhenxi; Zhang, Xianzhou; Zhou, Yuting; Zhang, Yangjian] Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Beijing 100101, Peoples R China. [Fu, Gang; Zhou, Yuting] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. RP Shen, ZX (通讯作者)，Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Lhasa Plateau Ecosyst Res Stn, Datun Rd, Beijing 100101, Peoples R China. EM shenzx@igsnrr.ac.cn TC 43 Z9 60 PD SEP-OCT PY 2012 VL 52 BP 27 EP 29 DI 10.1016/j.ejsobi.2012.05.004 UT WOS:000309092800005 DA 2023-03-23 ER PT J AU Liu, YZ Mu, JP Niklas, KJ Li, GY Sun, SC AF Liu, Yinzhan Mu, Junpeng Niklas, Karl J. Li, Guoyong Sun, Shucun TI Global warming reduces plant reproductive output for temperate multi-inflorescence species on the Tibetan plateau SO NEW PHYTOLOGIST DT Article AB Temperature is projected to increase more during the winter than during the summer in cold regions. The effects of winter warming on reproductive effort have not been examined for temperate plant species. Here, we report the results of experimentally induced seasonal winter warming (0.4 and 2.4 degrees C increases in growing and nongrowing seasons, respectively, using warmed and ambient open-top chambers in a Tibetan Plateau alpine meadow) for nine indeterminate-growing species producing multiple (single-flowered or multi-flowered) inflorescences and three determinate-growing species producing single inflorescences after a 3-yr period of warming. Warming reduced significantly flower number and seed production per plant for all nine multi-inflorescence species, but not for the three single-inflorescence species. Warming had an insignificant effect on the fruit to flower number ratio, seed size and seed number per fruit among species. The reduction in seed production was largely attributable to the decline in flower number per plant. The flowering onset time was unaffected for nine of the 12 species. Therefore, the decline in flower production and seed production in response to winter warming probably reflects a physiological response (e.g. metabolic changes associated with flower production). Collectively, the data indicate that global warming may reduce flower and seed production for temperate herbaceous species and will probably have a differential effect on single- vs multi-inflorescence species. C1 [Liu, Yinzhan; Li, Guoyong; Sun, Shucun] Chinese Acad Sci, Chengdu Inst Biol, ECORES Lab, Chengdu 610041, Peoples R China. [Mu, Junpeng; Sun, Shucun] Nanjing Univ, Dept Biol, Nanjing 210093, Jiangsu, Peoples R China. [Niklas, Karl J.] Cornell Univ, Dept Plant Biol, Ithaca, NY 14850 USA. RP Sun, SC (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, ECORES Lab, Chengdu 610041, Peoples R China. EM shcs@nju.edu.cn TC 62 Z9 68 PD JUL PY 2012 VL 195 IS 2 BP 427 EP 436 DI 10.1111/j.1469-8137.2012.04178.x UT WOS:000305472100016 DA 2023-03-23 ER PT J AU Ma, MJ Zhou, XH Ma, Z Du, GZ AF Ma, Miaojun Zhou, Xianhui Ma, Zhen Du, Guozhen TI Composition of the soil seed bank and vegetation changes after wetland drying and soil salinization on the Tibetan Plateau SO ECOLOGICAL ENGINEERING DT Article AB The primary goal was to address a question with regard to whether the seed bank be regarded as a potential as a source of seeds for saline-alkaline meadow restoration on the Tibetan Plateau. We collected soil samples, soil seed bank samples, sampled the vegetation in a seasonal wetland and in a saline-alkaline meadow, and used the NMDS (nonmetric multidimensional scaling) to evaluate the relationship of species composition between the seed banks and vegetation. The saline-alkaline meadow develops after drying of wetlands following disturbance. Soil properties, and seed density and species richness were compared. The seed density and species richness of the seed banks showed no difference between the two habitats. The NMDS results showed that composition of the vegetation of the two sites was obviously different, but that of the seed bank was not. The drying of the wetland altered plant community and soil properties. Persistent seed bank can be regarded a strategy of adaptation to current soil environment (high soil moisture or salinity). There was a significant negative effect on soil characteristics after wetland drying and subsequent salinization. If hydrology is restored, the seed bank will continue to be an importance source of diversity of propagules for saline-alkaline meadow restoration following disturbance. (C) 2012 Elsevier B.V. All rights reserved. C1 [Ma, Miaojun; Zhou, Xianhui; Ma, Zhen; Du, Guozhen] Lanzhou Univ, Sch Life Sci, Lanzhou 730000, Gansu, Peoples R China. RP Du, GZ (通讯作者)，Lanzhou Univ, Sch Life Sci, S Tianshui Rd 222, Lanzhou 730000, Gansu, Peoples R China. EM mamiaojun@gmail.com; zhouxianh@lzu.edu.cn; qinfenma@126.com; guozdu@lzu.edu.cn TC 36 Z9 43 PD JUL PY 2012 VL 44 BP 18 EP 24 DI 10.1016/j.ecoleng.2012.03.017 UT WOS:000305443100003 DA 2023-03-23 ER PT J AU Wu, XD Zhao, L Fang, HB Chen, J Pang, QQ Wang, ZW Chen, MJ Ding, YJ AF Wu, X. D. Zhao, L. Fang, H. B. Chen, J. Pang, Q. Q. Wang, Z. W. Chen, M. J. Ding, Y. J. TI Soil Enzyme Activities in Permafrost Regions of the Western Qinghai-Tibetan Plateau SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL DT Article AB Enzyme activities play key roles in the biochemical functioning of soils, in processes such as soil organic matter formation and degradation, and nutrient cycling. They are indicators of soil quality and key to soil ecosystem functioning. In this study, the effect of vegetation communities and soil properties on the activities of invertase, alkaline phosphatase, amylase, urease, cellulose, and catalase were investigated in permafrost regions of the middle and western Qinghai-Tibetan Plateau. This area is characterized by cold, arid steppe, with an active layer thicker than 2 m. The results demonstrated that soil enzyme activities were higher in Stipa roborowskyi Roshev. vegetation communities than those of Carex moorcroftii Falconer ex Boott communities. Soil enzyme activities were lowest in the alpine cold desert area. The activities per unit soil were primarily positively related to soil organic C (SOC) and moisture contents, and when activities were expressed as per unit C, they were primarily positively related to gravel content and negatively to moisture content. Results demonstrated that the vegetation communities, SOC, and moisture contents were important factors influencing soil enzyme activities, while permafrost, vegetation cover, and topographic factors played less important roles in the cold, arid area of the northwestern part of Qinghai-Tibetan Plateau. Potential SOC changes in this area were also investigated with regard to future climate change. C1 [Wu, X. D.; Zhao, L.; Fang, H. B.; Pang, Q. Q.; Wang, Z. W.] Chinese Acad Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, Lanzhou, Peoples R China. [Wu, X. D.; Zhao, L.; Fang, H. B.; Chen, J.; Pang, Q. Q.; Wang, Z. W.; Ding, Y. J.] Cold & Arid Reg Environm & Engn Res Inst, Lanzhou, Peoples R China. [Wu, X. D.; Fang, H. B.; Pang, Q. Q.; Wang, Z. W.; Ding, Y. J.] State Key Lab Cryospher Sci, Lanzhou, Peoples R China. [Chen, J.] State Key Lab Frozen Soil Engn, Lanzhou, Peoples R China. [Chen, M. J.] Chinese Acad Sci, Inst Soil Sci, Nanjing, Jiangsu, Peoples R China. RP Zhao, L (通讯作者)，Chinese Acad Sci, Cryosphere Res Stn Qinghai Tibetan Plateau, Lanzhou, Peoples R China. EM linzhao@lzb.ac.cn; dyj@lzb.ac.cn TC 25 Z9 34 PD JUL PY 2012 VL 76 IS 4 BP 1280 EP 1289 DI 10.2136/sssaj2011.0400 UT WOS:000306355900016 DA 2023-03-23 ER PT J AU Yang, YH Ji, CJ Ma, WH Wang, SF Wang, SP Han, WX Mohammat, A Robinson, D Smith, P AF Yang, Yuanhe Ji, Chengjun Ma, Wenhong Wang, Shifeng Wang, Shaopeng Han, Wenxuan Mohammat, Anwar Robinson, David Smith, Pete TI Significant soil acidification across northern China's grasslands during 1980s-2000s SO GLOBAL CHANGE BIOLOGY DT Article AB Anthropogenic acid deposition may lead to soil acidification, with soil buffering capacity regulating the magnitude of any soil pH change. However, little evidence is available from large-scale observations. Here, we evaluated changes in soil pH across northern China's grasslands over the last two decades using soil profiles obtained from China's Second National Soil Inventory during the 1980s and a more recent regional soil survey during 20012005. A transect from the central-southern Tibetan Plateau to the eastern Inner Mongolian Plateau, where Kriging interpolation provided robust predictions of the spatial distribution of soil pH, was then selected to examine pH changes during the survey period. Our results showed that soil pH in the surface layer had declined significantly over the last two decades, with an overall decrease of 0.63 units (95% confidence interval similar to=similar to 0.540.73 units). The decline of soil pH was observed in both alpine grasslands on the Tibetan Plateau and temperate grasslands on the Inner Mongolian Plateau. Soil pH decreased more intensively in low soil carbonate regions, while changes of soil pH showed no significant associations with soil cation exchange capacity. These results suggest that grassland soils across northern China have experienced significant acidification from the 1980s to 2000s, with soil carbonates buffering the increase in soil acidity. The buffering process may induce a large loss of carbon from soil carbonates and thus alter the carbon balance in these globally important ecosystems. C1 [Yang, Yuanhe; Ji, Chengjun; Wang, Shaopeng] Peking Univ, Dept Ecol, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China. [Yang, Yuanhe] Chinese Acad Sci, State Key Lab Vegetat & Environm Change, Inst Bot, Beijing 100093, Peoples R China. [Yang, Yuanhe; Wang, Shifeng; Robinson, David; Smith, Pete] Univ Aberdeen, Inst Biol & Environm Sci, Aberdeen AB24 3UU, Scotland. [Ma, Wenhong] Inner Mongolia Univ, Coll Life Sci, Hohhot 010021, Peoples R China. [Han, Wenxuan] China Agr Univ, Coll Resources & Environm Sci, Beijing 100193, Peoples R China. [Mohammat, Anwar] Chinese Acad Sci, Xinjiang Inst Ecol & Geog, Urumqi 830011, Peoples R China. RP Yang, YH (通讯作者)，Peking Univ, Dept Ecol, Key Lab Earth Surface Proc, Minist Educ, Beijing 100871, Peoples R China. EM yhyangpku@gmail.com TC 182 Z9 222 PD JUL PY 2012 VL 18 IS 7 BP 2292 EP 2300 DI 10.1111/j.1365-2486.2012.02694.x UT WOS:000304820300018 DA 2023-03-23 ER PT J AU Wang, GX Liu, GS Li, CJ AF Wang Genxu Liu Guangsheng Li Chunjie TI Effects of changes in alpine grassland vegetation cover on hillslope hydrological processes in a permafrost watershed SO JOURNAL OF HYDROLOGY DT Article AB Two main types of grasslands on the Qinghai-Tibet Plateau, alpine swamp and alpine meadow, were selected for this study. Monitoring plots were constructed on each type of grassland with varying degrees of vegetation degradation. The impacts of alpine grassland cover changes on the hillslope water cycle were analyzed in terms of runoff generation, precipitation interception, dew water formation, and soil water dynamics of the active layer, etc. The results showed that different types of grasslands led to different runoff generation regimes; namely, runoff varied linearly with precipitation in alpine swamp, whereas in alpine meadow, runoff exhibited an exponential precipitation-dependence. The decrease in vegetation cover in alpine swamp leads to a decrease in soil moisture content in the top 20 cm of the soil, a delay in the thawing start time in the spring, and a decrease in both surface runoff and subsurface interflow. In alpine meadow, however, the decrease in vegetation cover led to a significant increase in the depth of topsoil moisture content during the thawing period, earlier occurrence of thawing, and an increase in the runoff generation ratio. The alpine meadow vegetation canopy had a higher maximum interception ratio and saturation precipitation than alpine swamp vegetation. With the decrease in vegetation cover, the rainfall interception ratios decreased by almost an identical range in both the alpine meadow and alpine swamp grasslands. Dew water commonly occurs on alpine grassland, accounting for about 12.5-16.5% of precipitation in the same period, and thus, is an important component of the water cycle. With the degradation of vegetation, surface dew water decreased; however, the ratio of dew water formed in the air to the total amount of dew water rose significantly. At the hillslope scale, the changes of alpine vegetation cover had a great influence on the water cycle, which were partly attributed to that the changes of alpine vegetation cover directly altered the surface energy balance, surface water cycle processes, and the thermal and hydraulic properties of active soil. (C) 2012 Elsevier B.V. All rights reserved. C1 [Wang Genxu; Liu Guangsheng; Li Chunjie] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM wanggx@imde.ac.cn TC 64 Z9 78 PD JUN 11 PY 2012 VL 444 BP 22 EP 33 DI 10.1016/j.jhydrol.2012.03.033 UT WOS:000305108000003 DA 2023-03-23 ER PT J AU Bai, W Wang, GX Liu, GS AF Bai Wei Wang Genxu Liu Guangsheng TI Effects of elevated air temperatures on soil thermal and hydrologic processes in the active layer in an alpine meadow ecosystem of the Qinghai-Tibet Plateau SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB In this study, effects of elevated air temperatures on thermal and hydrologic process of the shallow soil in the active layer were investigated. Open-top chambers (OTCs) were utilized to increase air temperatures 1-2A degrees C in OTC-1 and 3-5A degrees C in OTC-2 in the alpine meadow ecosystem on the Qinghai-Tibetan Plateau. Results show that the annual air temperatures under OTC-1 and OTC-2 were 1.21A degrees C and 3.62A degrees C higher than the Control, respectively. The entirely-frozen period of shallow soil in the active layer was shortened and the fully thawed period was prolonged with temperature increase. The maximum penetration depth and duration of the negative isotherm during the entirely-frozen period decreased, and soil freezing was retarded in the local scope of the soil profile when temperature increased. Meanwhile, the positive isotherm during the fully-thawed period increased, and the soil thawing was accelerated. Soil moisture under different manipulations decreased with the temperature increase at the same depth. During the early freezing period and the early fullythawed period, the maximum soil moisture under the Control manipulation was at 0.2 m deep, whereas under OTC-1 and OTC-2 manipulations, the maximum soil moisture were at 0.4-0.5 m deep. These results indicate that elevated temperatures led to a decrease of the moisture in the surface soil. The coupled relationship between soil temperature and moisture was significantly affected by the temperature increase. During the freezing and thawing processes, the soil temperature and moisture under different manipulations fit the regression model given by the equation theta (V)=a/{;1+exp[b(TS+c)]}+d. C1 [Bai Wei] Lanzhou Jiaotong Univ, Sch Environm & Municipal Engn, Lanzhou 730070, Peoples R China. [Bai Wei; Wang Genxu] Lanzhou Univ, Coll Resource & Environm Sci, Lanzhou 730000, Peoples R China. [Wang Genxu; Liu Guangsheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. RP Wang, GX (通讯作者)，Lanzhou Univ, Coll Resource & Environm Sci, Lanzhou 730000, Peoples R China. EM baiwei915@163.com; wanggx@imde.ac.cn TC 7 Z9 8 PD APR PY 2012 VL 9 IS 2 BP 243 EP 255 DI 10.1007/s11629-012-2117-z UT WOS:000301788100011 DA 2023-03-23 ER PT J AU Zheng, Y Yang, W Sun, X Wang, SP Rui, YC Luo, CY Guo, LD AF Zheng, Yong Yang, Wei Sun, Xiang Wang, Shi-Ping Rui, Yi-Chao Luo, Cai-Yun Guo, Liang-Dong TI Methanotrophic community structure and activity under warming and grazing of alpine meadow on the Tibetan Plateau SO APPLIED MICROBIOLOGY AND BIOTECHNOLOGY DT Article AB Knowledge about methanotrophs and their activities is important to understand the microbial mediation of the greenhouse gas CH4 under climate change and human activities in terrestrial ecosystems. The effects of simulated warming and sheep grazing on methanotrophic abundance, community composition, and activity were studied in an alpine meadow soil on the Tibetan Plateau. There was high abundance of methanotrophs (1.2-3.4 x 10(8) pmoA gene copies per gram of dry weight soil) assessed by real-time PCR, and warming significantly increased the abundance regardless of grazing. A total of 64 methanotrophic operational taxonomic units (OTUs) were obtained from 1,439 clone sequences, of these OTUs; 63 OTUs (98.4%) belonged to type I methanotrophs, and only one OTU was Methylocystis of type II methanotrophs. The methanotroph community composition and diversity were not apparently affected by the treatments. Warming and grazing significantly enhanced the potential CH4 oxidation activity. There were significantly negative correlations between methanotrophic abundance and soil moisture and between methanotrophic abundance and NH4-N content. The study suggests that type I methanotrophs, as the dominance, may play a key role in CH4 oxidation, and the alpine meadow has great potential to consume more CH4 under future warmer and grazing conditions on the Tibetan Plateau. C1 [Zheng, Yong; Yang, Wei; Sun, Xiang; Guo, Liang-Dong] Chinese Acad Sci, State Key Lab Mycol, Inst Microbiol, Beijing 100101, Peoples R China. [Wang, Shi-Ping] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100085, Peoples R China. [Yang, Wei; Rui, Yi-Chao] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. [Luo, Cai-Yun] Chinese Acad Sci, NW Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. RP Guo, LD (通讯作者)，Chinese Acad Sci, State Key Lab Mycol, Inst Microbiol, Beijing 100101, Peoples R China. EM guold@im.ac.cn TC 70 Z9 87 PD MAR PY 2012 VL 93 IS 5 BP 2193 EP 2203 DI 10.1007/s00253-011-3535-5 UT WOS:000300657900036 DA 2023-03-23 ER PT J AU Zheng, XY Liu, XD Jiang, GB Wang, YW Zhang, QH Cai, YQ Cong, ZY AF Zheng, Xiaoyan Liu, Xiande Jiang, Guibin Wang, Yawei Zhang, Qinghua Cai, Yaqi Cong, Zhiyuan TI Distribution of PCBs and PBDEs in soils along the altitudinal gradients of Balang Mountain, the east edge of the Tibetan Plateau SO ENVIRONMENTAL POLLUTION DT Article AB Surface soils were collected in Balang Mountain to explore the environmental process of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) during air transport. The average concentrations of Sigma(25)PCBs and Sigma 13PBDEs in soils were 163 pg/g and 26 pg/g, respectively. The significant correlations between the concentrations of pollutants and total organic carbon (TOC) indicated the importance of TOC in accumulation potential of POPs. The slopes from fitted curves of PCBs were highly related with logK(oa), demonstrating that TOC dominates the soil-air exchange of PCBs. The TOC-normalized concentrations of contaminants in samples from below-treeline were higher than those from alpine meadow, probably due to the forest filter effect. The increasing trends of the concentrations with altitude from the alpine meadow samples, could be attributed to the mountain cold-trapping effect. And the weak cold-trapping effect of POPs might be due to the less precipitation in 2008 when comparing with those in 2006. (C) 2011 Elsevier Ltd. All rights reserved. C1 [Zheng, Xiaoyan; Jiang, Guibin; Wang, Yawei; Zhang, Qinghua; Cai, Yaqi] Chinese Acad Sci, State Key Lab Environm Chem & Ecotoxicol, Ecoenvironm Sci Res Ctr, Beijing 100085, Peoples R China. [Zheng, Xiaoyan] China Natl Environm Monitoring Ctr, Beijing 100012, Peoples R China. [Liu, Xiande] Chinese Res Inst Environm Sci, Beijing 100012, Peoples R China. [Cong, Zhiyuan] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100085, Peoples R China. RP Wang, YW (通讯作者)，Chinese Acad Sci, State Key Lab Environm Chem & Ecotoxicol, Ecoenvironm Sci Res Ctr, Beijing 100085, Peoples R China. EM xiaoyanzheng1978@gmail.com; xiande.liu@gmail.com; gbjiang@rcees.ac.cn; ywwang@rcees.ac.cn TC 54 Z9 64 PD FEB PY 2012 VL 161 BP 101 EP 106 DI 10.1016/j.envpol.2011.09.036 UT WOS:000300539300015 DA 2023-03-23 ER PT C AU Guo, N Li, YH Han, LY Wang, SP AF Guo, Ni Li, Yaohui Han, Lanyiing Wang, Suping GP IEEE TI THE EFFECTS OF CLIMATE CHANGE ON DIFFERENT TYPES OF GRASSLAND IN MAQU COUNTY IN NORTHEAST TIBETAN PLATEAU SO 2012 IEEE INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM (IGARSS) SE IEEE International Symposium on Geoscience and Remote Sensing IGARSS DT Proceedings Paper CT IEEE International Geoscience and Remote Sensing Symposium (IGARSS) CY JUL 22-27, 2012 CL Munich, GERMANY AB The Maqu County, located in the eastern Tibetan Plateau, is an important ecological function protected area on the state level in China, because of its typical grass type, geographic conditions and ecological environment. In this paper, the dynamic change of climate factors and the change characteristics of three types of grassland NDVI in the Maqu, and the relationships between the NDVI and the climatic factors were studied by using GIMMS NDVI data and meteorological data from January 1982 to December 2006 and the data of grassland types in the Maqu. The results showed that, the monthly temperature is increasing from 1982 to 2010 in the Maqu. There is no clear trend in the monthly or quarterly precipitation. The reference evapotranspiration trend for every month has displayed increasing trend. The NDVI for the most of the months were increasing in the growing season, with increase most significant in July and October. But the increase of NDVI in August was not significant. Among the three types of grassland, the NDVI in the Alpine grassland increased the most obviously and the trends for marshed grassland increased the least significantly. Climate change may be the main reason for the change of the NDVI. Human activities (such as overgrazing) was one of the reasons for the degradation of vegetation. C1 [Guo, Ni; Li, Yaohui; Han, Lanyiing; Wang, Suping] CMA, Inst Arid Meteorol, Lanzhou, Peoples R China. RP Guo, N (通讯作者)，CMA, Inst Arid Meteorol, Lanzhou, Peoples R China. TC 7 Z9 7 PY 2012 BP 1139 EP 1142 DI 10.1109/IGARSS.2012.6351347 UT WOS:000313189401089 DA 2023-03-23 ER PT J AU Zhang, XM Sheng, Y Li, J Wu, JC Chen, J Cao, YB AF Zhang, Xiumin Sheng, Yu Li, Jing Wu, Jichun Chen, Ji Cao, Yuanbing TI Changes of alpine ecosystem along the ground temperature of permafrost in the source region of Datong River in the Northeastern Qinghai-Tibet Plateau SO JOURNAL OF FOOD AGRICULTURE & ENVIRONMENT DT Article AB The current study analyzes the effects of the thermal state of permafrost on the alpine ecosystem based on investigation data from 92 vegetation spots sampled in 2010 and permafrost temperatures from an equivalent-elevation model in the Datong River source region, in the northeastern Qinghai-Tibet plateau in China. The interactions among the permafrost temperature, vegetation (the species diversity indices and biomass), and soil properties (moisture, pH and nutrients) are discussed. The results showed that with the increase of permafrost temperature, the species diversity indices and plant biomass of alpine swamp meadow firstly ascended and then decreased, whereas the value of alpine meadow had an opposite trend. Soil moisture, soil organic matter, soil total nitrogen, and soil total phosphorus changed with the permafrost temperature and rose to the maximum at a certain temperature range. Subsequently, the contents began to descend. In contrast, soil total potassium content had an opposite regularity with the increase of the temperature. The values were higher in alpine swamp meadow than in alpine meadow, except the soil total phosphorus. Soil pH had a good positive correlation with the permafrost temperature, and the contents of soil pH were higher in alpine meadow than in alpine swamp meadow. C1 [Zhang, Xiumin; Sheng, Yu; Li, Jing; Wu, Jichun; Chen, Ji; Cao, Yuanbing] Chinese Acad Sci, Cold & Arid Regions Environm & Engn Res Inst, State Key Lab Frozen Soil Engn, Lanzhou 730000, Gansu, Peoples R China. RP Sheng, Y (通讯作者)，Chinese Acad Sci, Cold & Arid Regions Environm & Engn Res Inst, State Key Lab Frozen Soil Engn, 320 Donggang W Rd, Lanzhou 730000, Gansu, Peoples R China. EM zhangxm@lzb.ac.cn; sheng@lzb.ac.cn TC 5 Z9 7 PD JAN PY 2012 VL 10 IS 1 BP 970 EP 976 PN 2 UT WOS:000300924300073 DA 2023-03-23 ER PT J AU Shen, MG Tang, YH Chen, J Zhu, XL Zheng, YH AF Shen, Miaogen Tang, Yanhong Chen, Jin Zhu, Xiaolin Zheng, Yinghua TI Influences of temperature and precipitation before the growing season on spring phenology in grasslands of the central and eastern Qinghai-Tibetan Plateau SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB Spatial variations in phenological responses to temperature have not been reported for grasslands of the Qinghai-Tibetan Plateau. Using satellite-derived normalized difference vegetation index and meteorological records from 1982 to 2006, we characterized the spatial patterns of grassland green-up onset in relation to air temperature and precipitation before the growing season ("preseason" henceforth) in the central and eastern plateau by combining linear programming with correlation analysis. Green-up onset near half of the meteorological stations was significantly correlated (p < 0.10) with precipitation and thermal spring onset (TSO) date based on the cumulative temperature less than 6 weeks before the onset. The green-up onset paralleled the advance in TSO in the southwestern, southeastern, eastern, and northeastern parts of the plateau. The TSO and preseason precipitation (PPT) explained part of the inter-annual phenological variations, with r(2) varying between 0.05 and 0.55 and averaging 0.28, and did not explain delay of green-up onset in some areas. Increasing preseason temperature tended to advance green-up onset in relatively moist areas. PPT exerted a stronger influence on green-up onset in drier areas. These results indicate spatial differences in the key environmental influences on spring phenology. To improve the ability to predict onset, ground-based community-level phenological studies and spatial scaling-up of the phenology-climate relationship will be necessary. (C) 2011 Elsevier B.V. All rights reserved. C1 [Chen, Jin] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. [Shen, Miaogen; Tang, Yanhong] Natl Inst Environm Studies, Div Environm Biol, Tsukuba, Ibaraki 3058506, Japan. [Zhu, Xiaolin] Ohio State Univ, Dept Geog, Columbus, OH 43210 USA. [Zheng, Yinghua] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. RP Chen, J (通讯作者)，Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China. EM chenjin@bnu.edu.cn TC 294 Z9 334 PD DEC 15 PY 2011 VL 151 IS 12 BP 1711 EP 1722 DI 10.1016/j.agrformet.2011.07.003 UT WOS:000297277200020 DA 2023-03-23 ER PT J AU Kato, T Hirota, M Tang, YH Wada, E AF Kato, Tomomichi Hirota, Mitsuru Tang, Yanhong Wada, Eitaro TI Spatial variability of CH4 and N2O fluxes in alpine ecosystems on the Qinghai-Tibetan Plateau SO ATMOSPHERIC ENVIRONMENT DT Article AB The intra- and inter-site spatial variability of methane (CH4) and nitrous oxide (N2O) fluxes were investigated in three alpine ecosystems at Haibei station on the Qinghai Tibetan Plateau (QTP) in summer 2005 and in sixteen alpine ecosystems with various vegetations across the QTP in summer 2006, respectively. The magnitude of average CH4 emissions from wetlands was at least 100 times larger than average CH4 uptake by grassland, suggesting that the entire QTP is likely to be a source of methane in summertime because of a significant fractional area of wetlands (similar to 2.2%) on the plateau. Intra-site investigation, with sixteen chambers, revealed a significant negative relationship of CH4 emissions with the C/N ratio of aboveground biomass and soil pH in the alpine wetland when all chambers were considered. Moreover, soil oxidation-reduction potential (ORP) had a remarkably strong influence on CH4 emissions for nine chambers above the water level, resulting in a negative exponential relationship. For N2O flux in alpine meadows, a negative relationship with both soil pH and livestock dung biomass was observed. Aboveground plant biomass and soil pH were important variables overall in wetlands. Inter-site investigation found positive and negative relationships between CH4 flux and soil biomass to 5 cm depth in nine grassland and seven wetland sites, respectively. N2O flux showed a moderately strong negative exponential relationship with the C/N ratio of surface soil in the grassland sites. In the wetlands, soil pH was negatively correlated with N2O flux, perhaps due to both reduced N2O release from suppressed nitrification and denitrification. (C) 2011 Elsevier Ltd. All rights reserved. C1 [Kato, Tomomichi; Wada, Eitaro] Japan Agcy Marine Earth Sci & Technol, Res Inst Global Change, Kanagawa 2360001, Japan. [Hirota, Mitsuru] Univ Tsukuba, Grad Sch Life & Environm Sci, Tsukuba, Ibaraki 3058572, Japan. [Tang, Yanhong] Natl Inst Environm Studies, Tsukuba, Ibaraki 3058506, Japan. RP Kato, T (通讯作者)，CEA Saclay, Lab Sci Climat & Environm, Bat 709 Orme des Merisiers, F-91191 Gif Sur Yvette, France. EM tomomichi.kat@lsce.ipsl.fr TC 57 Z9 62 PD OCT PY 2011 VL 45 IS 31 BP 5632 EP 5639 DI 10.1016/j.atmosenv.2011.03.010 UT WOS:000295070300026 DA 2023-03-23 ER PT J AU Miehe, G Bach, K Miehe, S Kluge, J Yang, YP La, D Co, S Wesche, K AF Miehe, Georg Bach, Kerstin Miehe, Sabine Kluge, Juergen Yang Yongping La Duo Co, Sonam Wesche, Karsten TI Alpine steppe plant communities of the Tibetan highlands SO APPLIED VEGETATION SCIENCE DT Article AB Aim: To present a first description of plant communities of the Tibetan alpine steppes based on floristically complete vegetation records as a baseline reference for future ecological and palaeoecological studies. These constitute the world's largest alpine biome, but their vegetation is virtually unknown. Due to their vast extent, they are relevant for functioning of large-scale climatic systems. In turn, arid and alpine biomes are suspected to be highly sensitive to ongoing climate change, underwent climate-driven changes during the Last Glacial Maximum and have been subject to overgrazing and desertification. Location: Northwestern Tibetan highlands (China: Xizang, Qinghai), 4200 to 5400 m a.s.l., total area ca. 800 000 km(2). Methods: Two hundred and fifty-three vegetation records with absolute percentage cover were classified based on expert knowledge and analysed by DCA; composition of plant functional types related to grazing resilience was also assessed. Results: Ten communities of alpine steppe were distinguished. A set of 11 alpine steppe species is distributed throughout the highlands, with a precipitation gradient between 350 mm yr(-1) (southeast) and 20 to 50 mm yr(-1) (northwest). The elevational range of more than 80% of species is larger than 1000 m. The data set comprises 30% endemic species, with ten endemic genera. Conclusions: The wide thermal and hygric range of many species and high rate of endemism do not support the idea of high sensitivity to climate change or occurrence of past climate-driven extinctions. The prevailing plant functional types are grazing resilient, and evidence for overgrazing is very limited. Cushion plants and dwarf shrubs, however, become increasingly rare around settlements, because they are uprooted for fuel. Hence, the world's largest arid alpine biome is apparently resilient to climatic changes and grazing. This contradicts common perceptions about arid and alpine ecosystems and therefore deserves intense multi-disciplinary research efforts. C1 [Miehe, Georg; Bach, Kerstin; Miehe, Sabine; Kluge, Juergen] Univ Marburg, Fac Geog, D-35032 Marburg, Germany. [Yang Yongping] CAS, Kunming Inst Bot, Heilongtan 650204, Yunnan, Peoples R China. [La Duo; Co, Sonam] Tibet Univ Lhasa, Dept Biol, Lhasa 850000, Ar Xizang, Peoples R China. [Wesche, Karsten] Senckenberg Museum Nat Hist Gorlitz, D-02806 Gorlitz, Germany. RP Miehe, G (通讯作者)，Univ Marburg, Fac Geog, Deutschhausstr 10, D-35032 Marburg, Germany. EM miehe@staff.uni-marburg.de; bachk@staff.uni-marburg.de; Sabine.Miehe@gmx.net; klugej@staff.uni-marburg.de; yangyp@itpcas.ac.cn; lhagdor2004@yahoo.com; Sonamtso@hotmail.com; karsten.wesche@senckenberg.de TC 46 Z9 51 PD OCT PY 2011 VL 14 IS 4 SI SI BP 547 EP 560 DI 10.1111/j.1654-109X.2011.01147.x UT WOS:000294600100008 DA 2023-03-23 ER PT J AU Yi, SH Zhou, ZY Ren, SL Xu, M Qin, Y Chen, SY Ye, BS AF Yi, Shuhua Zhou, Zhaoye Ren, Shilong Xu, Ming Qin, Yu Chen, Shengyun Ye, Baisheng TI Effects of permafrost degradation on alpine grassland in a semi-arid basin on the Qinghai-Tibetan Plateau SO ENVIRONMENTAL RESEARCH LETTERS DT Article AB Permafrost on the Qinghai-Tibetan Plateau (QTP) has degraded over the last few decades. Its ecological effects have attracted great concern. Previous studies focused mostly at plot scale, and hypothesized that degradation of permafrost would cause lowering of the water table and drying of shallow soil and then degradation of alpine grassland. However, none has been done to test the hypothesis at basin scale. In this study, for the first time, we investigated the relationships between land surface temperature (LST) and fractional vegetation cover (FVC) in different types of permafrost zone to infer the limiting condition (water or energy) of grassland growth on the source region of Shule River Basin, which is located in the north-eastern edge of the QTP. LST was obtained from MODIS Aqua products at 1 km resolution, while FVC was upscaled from quadrat (50 cm) to the same resolution as LST, using 30 m resolution NDVI data of the Chinese HJ satellite. FVC at quadrat scale was estimated by analyzing pictures taken with a multi-spectral camera. Results showed that (1) retrieval of FVC at quadrat scale using a multi-spectral camera was both more accurate and more efficient than conventional methods and (2) the limiting factor of vegetation growth transitioned from energy in the extreme stable permafrost zone to water in the seasonal frost zone. Our study suggested that alpine grassland would respond differently to permafrost degradation in different types of permafrost zone. Future studies should consider overall effects of permafrost degradation, and avoid the shortcomings of existing studies, which focus too much on the adverse effects. C1 [Yi, Shuhua; Zhou, Zhaoye; Ren, Shilong; Xu, Ming; Qin, Yu; Chen, Shengyun; Ye, Baisheng] Chinese Acad Sci, State Key Lab Cryosphere Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Yi, SH (通讯作者)，Chinese Acad Sci, State Key Lab Cryosphere Sci, Cold & Arid Reg Environm & Engn Res Inst, 320 Donggang W Rd, Lanzhou 730000, Peoples R China. EM yis@lzb.ac.cn TC 80 Z9 97 PD OCT-DEC PY 2011 VL 6 IS 4 AR 045403 DI 10.1088/1748-9326/6/4/045403 UT WOS:000298674700055 DA 2023-03-23 ER PT J AU Li, Q Lu, HY Zhu, LP Wu, NQ Wang, JB Lu, XM AF Li, Quan Lu, Houyuan Zhu, Liping Wu, Naiqin Wang, Junbo Lu, Xinmiao TI Pollen-inferred climate changes and vertical shifts of alpine vegetation belts on the northern slope of the Nyainqentanglha Mountains (central Tibetan Plateau) since 8.4 kyr BP SO HOLOCENE DT Article AB Fossil pollen from Nam Co and modern pollen from altitudinal vegetation belts around the lake are investigated to reveal alpine vegetation succession in response to climate changes during the Holocene in the central Tibetan Plateau. The discriminant analysis on 37 topsoil samples shows that pollen samples from alpine steppe at lower elevations (<4800 m) and alpine meadow on upper slopes (4800-5200 m) can be distinguished by their pollen assemblages. Samples from alpine steppe contain more Artemisia (25.1%) and Poaceae pollen (11.5%), whereas those from alpine meadow are dominated by Cyperaceae pollen (>60%). Our result indicates that the pollen ratio of Artemisia to Cyperaceae (A/Cy) can be used as an indicator of the vertical shift of vegetation belts and temperature changes in the central Tibetan Plateau as suggested by previous studies. A history of the vertical shift of vegetation belts on the northern slope of Nyainqentanglha Mountains and climate changes since 8.4 kyr BP are thus recovered by 198 fossil pollen assemblages from a 332 cm core of Nam Co. Paleovegetation reconstructed from fossil pollen assemblages through discriminant analysis shows a general downward shift of altitudinal vegetation belts, suggesting a decline in the temperature trend since 8.4 kyr BP. This result is consistent with the reduction of A/Cy ratios. The fossil pollen record also reveals warm and wet climate during the early to mid Holocene, and cold and dry conditions during the late Holocene in the Nam Co area. A comparison of Holocene climatic reconstructions across the Plateau indicates that termination of maximum moisture at around 6-5.5 kyr BP in our record is associated with the southeastward retreat of the Southwest Monsoon. C1 [Li, Quan; Lu, Houyuan; Wu, Naiqin] Chinese Acad Sci, Inst Geol & Geophys, Key Lab Cenozo Geol & Environm, Beijing 100029, Peoples R China. [Zhu, Liping; Wang, Junbo; Lu, Xinmiao] Chinese Acad Sci, Inst Tibetan Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100029, Peoples R China. RP Li, Q (通讯作者)，Chinese Acad Sci, Inst Geol & Geophys, Key Lab Cenozo Geol & Environm, Beijing 100029, Peoples R China. EM quanli_cas@163.com TC 52 Z9 63 PD SEP PY 2011 VL 21 IS 6 BP 939 EP 950 DI 10.1177/0959683611400218 UT WOS:000294043000005 DA 2023-03-23 ER PT J AU Liu, HW Zhou, L Liu, W Zhou, HK AF Liu, Hanwu Zhou, Li Liu, Wei Zhou, Huakun TI USING A CELLULAR-AUTOMATA MODEL TO INVESTIGATE THE EFFECTS OF GRAZING ON PLATEAU PIKA POPULATION DYNAMICS SO INTERNATIONAL JOURNAL OF BIOMATHEMATICS DT Article AB The plateau pika is a keystone species of Qinghai-Tibet plateau, but its overabundance aggravates the degradation of alpine meadow. Grazing is the most convenient manner to utilize alpine meadow. Grazing would change vegetation condition, that is, change the habitat of plateau pika and so lead to variation of plateau pika population. Based on ecological characteristics of plateau pika and alpine meadow, a cellular-automata model is established to investigate the influence of grazing on dynamics of plateau pika population. Vegetation shortens with the increase of grazing intensity. When grazing intensity is light, the height of vegetation under summer grazing, continuous grazing, rotational grazing and winter grazing decrease in turn. The ACC (average carrying capacity of plateau pika) is higher on degraded meadow and is lower on undegraded meadow. On undegraded meadow grazing affects the value of ACC, whereas, on degraded meadow grazing has slight effect on it. On undegraded meadow, plateau pika occupies all cells speedly, the amount of damaged cells and the average amount of live holes in occupied cells decrease or hold the line on temporal dimension. On degraded meadow, the dispersal of plateau pika is restrained, the amount of damaged cells and the average amount of live holes in occupied cells increase on temporal dimension. C1 [Liu, Hanwu] Yuncheng Univ, Dept Appl Math, Yuncheng 044000, Shanxi, Peoples R China. [Zhou, Li; Liu, Wei; Zhou, Huakun] Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Peoples R China. RP Liu, HW (通讯作者)，Yuncheng Univ, Dept Appl Math, Yuncheng 044000, Shanxi, Peoples R China. EM liuhanwu-china@163.com TC 5 Z9 5 PD SEP PY 2011 VL 4 IS 3 BP 275 EP 287 DI 10.1142/S179352451100126X UT WOS:000295410000002 DA 2023-03-23 ER PT J AU Jin, L Zhang, GQ Wang, XJ Dou, CY Chen, M Lin, SS Li, YY AF Jin, Liang Zhang, Guiqi Wang, Xiaojuan Dou, Cunyan Chen, Mu Lin, Shuangshuang Li, Yuanyuan TI Arbuscular mycorrhiza regulate inter-specific competition between a poisonous plant, Ligularia virgaurea, and a co-existing grazing grass, Elymus nutans, in Tibetan Plateau Alpine meadow ecosystem SO SYMBIOSIS DT Article AB In order to investigate the function of arbuscular mycorrhizae in Tibetan Plateau Alpine meadow ecosystems, experiments were carried out to evaluate the influence of arbuscular mycorrhizal (AM) fungi on inter-specific competition between the poisonous plant, Ligularia virgaurea, and the grazing grass, Elymus nutans, at different relative densities. Our results showed that the biomass of L. virgaurea significantly declined in AM treatments while the biomass of E. nutans increased in our inter-specific competition system. Relative yields and root/shoot ratios of these two species indicated that AM fungi had a significant influence on the growth of L. virgaurea and E. nutans. This implies that arbuscular mycorrhiza do not benefit both plant species equally but rather contribute to the growth of E. nutans more than L. virgaurea. We thus provide evidence that AM fungi could regulate plant interactions and influence the plant community structure in the Tibetan Plateau Alpine meadow ecosystem. C1 [Jin, Liang; Zhang, Guiqi; Wang, Xiaojuan; Dou, Cunyan; Chen, Mu; Lin, Shuangshuang; Li, Yuanyuan] Lanzhou Univ, Sch Pastoral Agr Sci & Technol, Lanzhou 730020, Peoples R China. RP Wang, XJ (通讯作者)，Lanzhou Univ, Sch Pastoral Agr Sci & Technol, POB 61, Lanzhou 730020, Peoples R China. EM xiaojuanwang@lzu.edu.cn TC 12 Z9 22 PD AUG PY 2011 VL 55 IS 1 BP 29 EP 38 DI 10.1007/s13199-011-0141-3 UT WOS:000298499300004 DA 2023-03-23 ER PT J AU Miehe, G Miehe, S Bach, K Nolling, J Hanspach, J Reudenbach, C Kaiser, K Wesche, K Mosbrugger, V Yang, YP Ma, YM AF Miehe, G. Miehe, S. Bach, K. Noelling, J. Hanspach, J. Reudenbach, C. Kaiser, K. Wesche, K. Mosbrugger, V. Yang, Y. P. Ma, Y. M. TI Plant communities of central Tibetan pastures in the Alpine Steppe/Kobresia pygmaea ecotone SO JOURNAL OF ARID ENVIRONMENTS DT Article AB Eleven plant communities of the central Tibetan ecotone (31 degrees 20'-33 degrees 00'N/89 degrees 00'-92 degrees 10'E) between the Kobresia pygmaea grazing pastures of the eastern highlands and the open short grass steppe with cushion plants ("Alpine Steppe") of the north-western highlands have been described on the basis of 189 plot-based floristically complete vegetation records. In parallel, remote sensing techniques distinguish four main land-use cover types. Our hypotheses are: (1) The plant communities of the central Tibetan highlands are grazing-adapted and resilient to degradation. (2) In contrast to grazing resilient plant functional types, the turf cover of the K. pygmaea pastures and the Kobresia schoenoides wetlands is degradable through desiccation, periglacial processes, soil-dwelling small mammals and livestock. Five grazing-related plant functional traits are introduced. Grazing tolerance is the prevalent functional type. Species with no specific protection against grazing make up not more than 6% of the total cover. Unpalatable plants cover up to 8%. Only the azonal K. schoenoides swamps - the indispensable winter grazing reserve have been widely degraded and depleted by 75%, being replaced by Carex sagaensis grazing pastures. It can be foreseen that governmental policy of sedentarisation of nomads will lead to reduced grazing mobility and degradation of winter grazing reserves. (C) 2011 Elsevier Ltd. All rights reserved. C1 [Miehe, G.; Miehe, S.; Bach, K.; Noelling, J.; Reudenbach, C.] Univ Marburg, Fac Geog, D-35032 Marburg, Germany. [Hanspach, J.] UFZ Helmholtz Ctr Environm Res, D-04318 Leipzig, Germany. [Kaiser, K.] Acatech German Acad Sci & Engn, D-10177 Berlin, Germany. [Wesche, K.] Senckenberg Museum Nat Hist Gorlitz, D-02806 Gorlitz, Germany. [Mosbrugger, V.] Senckenberg Nat Forschenden Gesell, Forschungsinst, Senckenberg, D-60325 Frankfurt, Germany. [Mosbrugger, V.] Senckenberg Nat Forschenden Gesell, Nat Museum, D-60325 Frankfurt, Germany. [Yang, Y. P.; Ma, Y. M.] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100085, Peoples R China. RP Bach, K (通讯作者)，Univ Marburg, Fac Geog, Deutschhausstr 10, D-35032 Marburg, Germany. EM bachk@staff.uni-marburg.de TC 62 Z9 69 PD AUG PY 2011 VL 75 IS 8 BP 711 EP 723 DI 10.1016/j.jaridenv.2011.03.001 UT WOS:000291624200006 DA 2023-03-23 ER PT J AU Xu, WX Gu, S Zhao, XQ Xiao, JS Tang, YH Fang, JY Zhang, J Jiang, S AF Xu, Weixin Gu, Song Zhao, XinQuan Xiao, Jianshe Tang, Yanhong Fang, Jingyun Zhang, Juan Jiang, Sha TI High positive correlation between soil temperature and NDVI from 1982 to 2006 in alpine meadow of the Three-River Source Region on the Qinghai-Tibetan Plateau SO INTERNATIONAL JOURNAL OF APPLIED EARTH OBSERVATION AND GEOINFORMATION DT Article AB Using satellite-observed Normalized Difference Vegetation Index (NDVI) data and Rotated Empirical Orthogonal Function (REOF) method, we analyzed the spatio-temporal variation of vegetation during growing seasons from May to September in the Three-River Source Region, alpine meadow in the Qinghai-Tibetan Plateau from 1982 to 2006. We found that NDVI in the centre and east of the region, where the vegetation cover is low, showed a consistent but slight increase before 2003 and remarkable increase in 2004 and 2005. Impact factors analysis indicted that among air temperature, precipitation, humid index, soil surface temperature, and soil temperature at 10 cm and 20 cm depth, annual variation of NDVI was highly positive correlated with the soil surface temperature of the period from March to July. Further analysis revealed that the correlation between the vegetation and temperature was insignificant before 1995, but statistically significant from 1995. The study indicates that temperature is the major controlling factor of vegetation change in the Three-River Source Region, and the currently increase of temperature may increase vegetation coverage and/or density in the area. In addition, ecological restoration project started from 2005 in Three-River Source Region has a certain role in promoting the recovery of vegetation. (C) 2011 Elsevier B.V. All rights reserved. C1 [Gu, Song; Jiang, Sha] Nankai Univ, Coll Life Sci, Tianjin 300071, Peoples R China. [Xu, Weixin; Gu, Song; Zhao, XinQuan] Chinese Acad Sci, NW Inst Plateau Biol, Xining, Peoples R China. [Xu, Weixin; Xiao, Jianshe; Zhang, Juan] Meteorol Inst Qinghai Prov, Xining, Peoples R China. [Xu, Weixin] Chinese Acad Sci, Grad Univ, Beijing, Peoples R China. [Tang, Yanhong] Natl Inst Environm Studies, Tsukuba, Ibaraki 3058506, Japan. [Fang, Jingyun] Peking Univ, Coll Urban & Environm Sci, Beijing 100871, Peoples R China. RP Gu, S (通讯作者)，Nankai Univ, Coll Life Sci, 94 Weijin Rd, Tianjin 300071, Peoples R China. EM songgu@nankai.edu.cn TC 81 Z9 94 PD AUG PY 2011 VL 13 IS 4 BP 528 EP 535 DI 10.1016/j.jag.2011.02.001 UT WOS:000292489900002 DA 2023-03-23 ER PT J AU Li, GY Liu, YZ Frelich, LE Sun, SC AF Li, Guoyong Liu, Yinzhan Frelich, Lee E. Sun, Shucun TI Experimental warming induces degradation of a Tibetan alpine meadow through trophic interactions SO JOURNAL OF APPLIED ECOLOGY DT Article AB P>1. It is well known that climate change alters abiotic factors (temperature and water availability) that directly affect ecosystem properties. However, less is known about the indirect impacts of climate change on ecosystem structure and function. Here, we show that experimental warming may deteriorate ecosystems via trophic interactions. 2. In a Tibetan alpine meadow, plant species composition, size, coverage and above-ground biomass were investigated to reveal the effect of artificial warming (c. 1 degrees C mean annual temperature at the soil surface), which was accomplished using warmed and ambient open top chambers. In addition, rodent damage to plants was assessed. 3. The dicot forb silverweed Potentilla anserina increased significantly, while other species groups remained unchanged or decreased in plant community dominance rank after 2 years of artificial warming. The change in community structure was attributed to the difference in biomass allocation and growth form among species. 4. In the third year, plateau zokors Myospalax fontanierii, a widespread rodent herbivore, damaged plants in the warmed chambers, while leaving plants in the ambient chambers mostly undamaged. Above-ground biomass was found to be smaller in the warmed chambers than the controls in the third year, in contrast to the trend of the first 2 years. In addition, zokor burrow density was positively correlated with silverweed biomass and its dominance within communities, which was consistent with findings of independent field investigations that silverweed-dominated plots were more likely to be visited and damaged by the zokors than sites-dominated by grass species. 5. Synthesis and applications. The top-down negative effect of zokor damage on above-ground biomass in the warmed chambers was induced by the bottom-up effect of changes in species composition and community structure on zokor foraging behaviour, which were driven by artificial warming. Such trophic interactions may invalidate some predictions of ecological effects by current species-climate envelope models. Furthermore, because management measures including increasing the water table, planting grass and moderate cattle grazing may prevent silverweed dominance, we suggest that these interventions could be employed to control zokor damage in alpine meadows that are predicted to be drier and warmer in the future. C1 [Li, Guoyong; Liu, Yinzhan; Sun, Shucun] Chinese Acad Sci, ECORES Lab, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Frelich, Lee E.] Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. [Sun, Shucun] Nanjing Univ, Dept Biol, Nanjing 210093, Peoples R China. RP Sun, SC (通讯作者)，Chinese Acad Sci, ECORES Lab, Chengdu Inst Biol, Chengdu 610041, Peoples R China. EM shcs@nju.edu.cn TC 64 Z9 72 PD JUN PY 2011 VL 48 IS 3 BP 659 EP 667 DI 10.1111/j.1365-2664.2011.01965.x UT WOS:000290587100019 DA 2023-03-23 ER PT J AU Liu, YZ Reich, PB Li, GY Sun, SC AF Liu, Yinzhan Reich, Peter B. Li, Guoyong Sun, Shucun TI Shifting phenology and abundance under experimental warming alters trophic relationships and plant reproductive capacity SO ECOLOGY DT Article AB Phenological mismatches due to climate change may have important ecological consequences. In a three-year study, phenological shifts due to experimental warming markedly altered trophic relationships between plants and insect herbivores, causing a dramatic decline of reproductive capacity for one of the plant species. In a Tibetan meadow, the gentian (Gentiana formosa) typically flowers after the peak larva density of a noctuid moth (Melanchra pisi) that primarily feeds on a dominant forb (anemone, Anemone trullifolia var. linearis). However, artificial warming of similar to 1.5 degrees C advanced gentian flower phenology and anemone vegetative phenology by a week, but delayed moth larvae emergence by two weeks. The warming increased larval density 10-fold, but decreased anemone density by 30%. The phenological and density shifts under warmed conditions resulted in the insect larvae feeding substantially on the gentian flowers and ovules; there was similar to 100-fold more damage in warmed than in unwarmed chambers. This radically increased trophic connection reduced gentian plant reproduction and likely contributed to its reduced abundance in the warmed chambers. C1 [Sun, Shucun] Nanjing Univ, Dept Biol, Nanjing 210093, Peoples R China. [Liu, Yinzhan; Li, Guoyong; Sun, Shucun] Chinese Acad Sci, Chengdu Inst Biol, ECORES Lab, Chengdu 610041, Peoples R China. [Reich, Peter B.] Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. RP Sun, SC (通讯作者)，Nanjing Univ, Dept Biol, 22 Hankou Rd, Nanjing 210093, Peoples R China. EM shcs@nju.edu.cn TC 103 Z9 114 PD JUN PY 2011 VL 92 IS 6 BP 1201 EP 1207 DI 10.1890/10-2060.1 UT WOS:000292633900002 DA 2023-03-23 ER PT J AU Wang, GX Bai, W Li, N Hu, HC AF Wang, Genxu Bai, Wei Li, Na Hu, Hongchang TI Climate changes and its impact on tundra ecosystem in Qinghai-Tibet Plateau, China SO CLIMATIC CHANGE DT Article AB Alpine ecosystems in permafrost region are extremely sensitive to climate change. The headwater regions of Yangtze River and Yellow River of the Qinghai-Tibet plateau permafrost area were selected. Spatial-temporal shifts in the extent and distribution of tundra ecosystems were investigated for the period 1967-2000 by landscape ecological method and aerial photographs for 1967, and satellite remote sensing data (the Landsat's TM) for 1986 and 2000. The relationships were analyzed between climate change and the distribution area variation of tundra ecosystems and between the permafrost change and tundra ecosystems. The responding model of tundra ecosystem to the combined effects of climate and permafrost changes was established by using statistic regression method, and the contribution of climate changes and permafrost variation to the degradation of tundra ecosystems was estimated. The regional climate exhibited a tendency towards significant warming and desiccation with the air temperature increased by 0.4-0.67A degrees C/10a and relative stable precipitation over the last 45 years. Owing to the climate continuous warming, the intensity of surface heat source (HI) increased at the average of 0.45 W/m(2) per year, the difference of surface soil temperature and air temperature (DT) increased at the range of 4.1A degrees C-4.5A degrees C, and the 20-cm depth soil temperature within the active layer increased at the range of 1.1A degrees C-1.4A degrees C. The alpine meadow and alpine swamp meadow were more sensitive to permafrost changes than alpine steppe. The area of alpine swamp meadow decreased by 13.6-28.9%, while the alpine meadow area decreased by 13.5-21.3% from 1967 to 2000. The contributions of climate change to the degradation of the alpine meadow and alpine swamp was 58-68% and 59-65% between 1967 and 2000. The synergic effects of climate change and permafrost variation were the major drivers for the observed degradation in tundra ecosystems of the Qinghai-Tibet plateau. C1 [Wang, Genxu; Li, Na] Chinese Acad Sci, Key Lab Mt Environm Evolvement & Regulat, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Wang, Genxu; Bai, Wei; Hu, Hongchang] Lanzhou Univ, Nat & Environm Coll, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Key Lab Mt Environm Evolvement & Regulat, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM wanggx@imde.ac.cn TC 85 Z9 100 PD JUN PY 2011 VL 106 IS 3 BP 463 EP 482 DI 10.1007/s10584-010-9952-0 UT WOS:000290448700007 DA 2023-03-23 ER PT J AU Wu, GL Li, W Zhao, LP Shi, ZH AF Wu Gao-Lin Li Wei Zhao Ling-Ping Shi Zhi-Hua TI Artificial Management Improves Soil Moisture, C, N and P in an Alpine Sandy Meadow of Western China SO PEDOSPHERE DT Article AB Regeneration of degraded grassland ecosystems is a significant issue in restoration ecology globally. To understand the effects of artificial management measures on alpine meadows, we surveyed topsoil properties including moisture, organic carbon (SOC), nitrogen (N), and phosphorus (P) contents five years after fencing and fencing + reseeding management practices in a sandy meadow in the eastern Qinghai-Tibetan Plateau, northwestern China. Both the fencing arid fencing + reseeding management practices significantly increased soil moisture storage, SOC, total N, available N, total P, and available P, as compared to the unmanaged control. Fencing plus reseeding was more effective than fencing alone for improving soil C, N, and P contents. These suggested that rehabilitation by reseeding and fencing generally had favorable effects on the soil properties in degraded sandy alpine meadows, and was an effective approach for restoration of degraded meadow ecosystems of the Qinghai-Tibetan Plateau. C1 [Wu Gao-Lin; Li Wei; Zhao Ling-Ping; Shi Zhi-Hua] NW A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China. [Wu Gao-Lin; Li Wei; Shi Zhi-Hua] Chinese Acad Sci, Inst Soil & Water Conservat, Yangling 712100, Peoples R China. [Wu Gao-Lin; Li Wei] Lanzhou Univ, Key Lab Arid & Grassland Ecol, Minist Educ, Lanzhou 730000, Peoples R China. [Wu Gao-Lin; Li Wei; Shi Zhi-Hua] Minist Water Resource, Yangling 712100, Peoples R China. RP Wu, GL (通讯作者)，NW A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Peoples R China. EM gaolinwu@gmail.com TC 16 Z9 20 PD JUN PY 2011 VL 21 IS 3 BP 407 EP 412 DI 10.1016/S1002-0160(11)60142-2 UT WOS:000291290700015 DA 2023-03-23 ER PT J AU Yang, ZP Hua, OY Zhang, XZ Xu, XL Zhou, CP Yang, WB AF Yang, Zhaoping Hua Ouyang Zhang, Xianzhou Xu, Xingliang Zhou, Caiping Yang, Wenbin TI Spatial variability of soil moisture at typical alpine meadow and steppe sites in the Qinghai-Tibetan Plateau permafrost region SO ENVIRONMENTAL EARTH SCIENCES DT Article AB Permafrost degradation has the potential to significantly change soil moisture. The objective of this study was to assess the variability of soil moisture in a permafrost region using geostatistical techniques. The experiment was conducted in August 2008 in alpine steppe and meadow located in the Qinghai-Tibetan Plateau permafrost region. Four soil depths (0-10, 10-20, 20-30 and 30-40 cm) were analyzed using frequency domain reflectometry, and sampling made of 80 points in a 10 m x 10 m grid were sampled. Soil moisture was analyzed using classical statistics to appropriately describe central tendency and dispersion, and then using geostatistics to describe spatial variability. Classical statistical method indicated that soil moisture in the permafrost region had a normal distribution pattern. Mean surface soil moisture in alpine meadow was higher than that in alpine steppe. The semivariograms showed that soil moisture variability in alpine cold steppe was larger than that in alpine meadow, which decreased with depths. Nugget values in alpine steppe were low (0.1-4.5), in contrast to alpine cold meadow. Soil moisture in alpine steppe had highly structured spatial variability with more than 93.4% spatial heterogeneity, and the range decreased with depth. Soil moisture content in alpine cold meadow had a moderate spatial dependence with a range of 51.3-169.2 m, increasing with depth. C1 [Yang, Zhaoping; Hua Ouyang; Zhang, Xianzhou; Xu, Xingliang; Zhou, Caiping; Yang, Wenbin] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. [Yang, Zhaoping] Minist Environm Protect, Nanjing Inst Environm Sci, Nanjing 210042, Peoples R China. [Hua Ouyang] Int Ctr Integrated Mt Dev, Kathmandu, Nepal. [Yang, Zhaoping] Chinese Acad Sci, Grad Sch, Beijing 100049, Peoples R China. RP Hua, OY (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing 100101, Peoples R China. EM ohua@igsnrr.ac.cn TC 33 Z9 35 PD JUN PY 2011 VL 63 IS 3 BP 477 EP 488 DI 10.1007/s12665-010-0716-y UT WOS:000290494100004 DA 2023-03-23 ER PT J AU Zhou, XL Yan, YE Wang, H Zhang, F Wu, LY Ren, JZ AF Zhou Xiaolei Yan Yuee Wang Hui Zhang Feng Wu Liyu Ren Jizhou TI Assessment of eco-environment vulnerability in the northeastern margin of the Qinghai-Tibetan Plateau, China SO ENVIRONMENTAL EARTH SCIENCES DT Article AB The northeastern margin of the Qinghai-Tibetan Plateau is typically a vulnerable eco-environment where an overload of alpine meadows and serious soil degeneration have led to vulnerability to natural disasters. Consequently, this vulnerable eco-environment does not allow for rapid socioeconomic development, resulting in weak potential for sustainable development. The northeastern margin of the Qinghai-Tibetan Plateau in China is used for this case study, which sets up 17 impact factors of eco-environment vulnerability (EEV) to assess the indexes, including natural impact factors, economic impact factors and social impact factors. Subsequently, the study uses an analytic hierarchy process to endow index weights and proposes an assessment model of G-1-Sigma(n)(i)(=1)P(i).W(i) + min Sigma(n)(i=1)P(i).W(i) )to analyze and assess the dynamic changes in the EEV of the study area from 1987-2008. Finally, the correlation of the EEV and 17 impact factors is analyzed. C1 [Zhou Xiaolei; Yan Yuee] Forest Inventory & Planning Inst Gansu Prov, Lanzhou 730020, Gansu, Peoples R China. [Wang Hui; Wu Liyu] Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China. [Zhang Feng] Lanzhou Univ, Key Lab Arid & Grassland Agroecol, Minist Educ, Lanzhou 730000, Peoples R China. [Ren Jizhou] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730000, Peoples R China. RP Zhou, XL (通讯作者)，Forest Inventory & Planning Inst Gansu Prov, Duanjiatan Rd 1234, Lanzhou 730020, Gansu, Peoples R China. EM atbeijing2008@gmail.com TC 10 Z9 17 PD JUN PY 2011 VL 63 IS 4 BP 667 EP 674 DI 10.1007/s12665-010-0731-z UT WOS:000290962000001 DA 2023-03-23 ER PT J AU Li, R Dao, ZL Li, H AF Li, Rong Dao, Zhiling Li, Heng TI Seed Plant Species Diversity and Conservation in the Northern Gaoligong Mountains in Western Yunnan, China SO MOUNTAIN RESEARCH AND DEVELOPMENT DT Article AB Plant species diversity was surveyed in the northern Gaoligong Mountains of western Yunnan, China, from 1990 to 2006. During the floristic surveys of seed plants, 2514 native species and 302 varieties (or subspecies) belonging to 778 genera in 171 families were recorded. We also found that 12 families are endemic to eastern Asia, 14 genera and 1232 taxa are endemic to China, and 132 taxa are endemic to the northern Gaoligong Mountains. According to the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria, 25 threatened taxa identified in the survey are endemic to this region. The flora is rich because of the role the northern Gaoligong Mountains played as a center of species diversification during the uplift of the eastern rim of the Tibetan Plateau in the Quaternary and as a refuge during the last glacial maximum. Unfortunately, this biodiversity faces massive threats because of the combined effect of habitat destruction or fragmentation and overexploitation of natural resources. Taking into consideration that human population growth will further increase pressure on this biodiversity in the near future, we suggest that conservation priority be given to the endemic plants, as well as to the habitats of primarily evergreen broad-leaved forest, coniferous broad-leaved mixed forest, and alpine shrub and meadows. C1 [Li, Rong; Dao, Zhiling; Li, Heng] Chinese Acad Sci, Key Lab Biodivers & Biogeog, Kunming Inst Bot, Kunming 650204, Yunnan Province, Peoples R China. RP Li, H (通讯作者)，Chinese Acad Sci, Key Lab Biodivers & Biogeog, Kunming Inst Bot, 132 Lanhei Rd, Kunming 650204, Yunnan Province, Peoples R China. EM liheng@mail.kib.ac.cn TC 15 Z9 18 PD MAY PY 2011 VL 31 IS 2 BP 160 EP 165 DI 10.1659/MRD-JOURNAL-D-10-00056.1 UT WOS:000291468800010 DA 2023-03-23 ER PT J AU Wang, LQ Yi, CL AF Wang, Liqiang Yi, Chaolu TI Properties and periglacial processes in alpine meadow soils, western Nyaingentanglha Mountains, Tibet SO QUATERNARY INTERNATIONAL DT Article; Proceedings Paper CT 24th Himalaya-Karakorum-Tibet Workshop CY AUG 11-14, 2009 CL Beijing, PEOPLES R CHINA AB One hundred and three samples were collected from nine soil profiles in alpine meadows on glacial moraines in two valleys on the northwestern slope of the West Nyainqentanglha Mountains, central Tibet. Properties measured were soil organic carbon (SOC), soil organic matter (SOM), principal anions and cations, total nitrogen, available nitrogen, pH, water content and grain size. High concentrations of SO(4)(2-), HCO(3)(-) and Cl(-) and lack of CO(3)(2-) are consistent with the acidity of the soil: pH < 6.21. Na(+) and K(+) are concentrated at depths of 0.2-0.4 m. A high concentration of Ca(2+) in the profiles indicates that leaching is weak. Sand and pebbles are dominant in soils with low clay content. These characteristics all indicate that the soil, which began to form in late Holocene time, is not well developed. The SOM and SOC contents are closely correlated and decrease with depth. Thus. SOM determined by the simple and quick loss on ignition method (LOI) can be substituted for SOC determined by the time-consuming and expensive Walkley-Black method (WB). Both SOM and SOC decrease with depth, but in contrast to a commonly reported result, their ratio, SOM/SOC, does not increase with depth in some of our profiles. This is attributed to periglacial processes that prevent organic matter with oxygen-functional groups from moving downward in the soil profiles. Periglacial processes may also disturb the soil layers through gelifluction. Consequently organic carbon does not decrease with depth in the profiles as it commonly does in low altitude areas. This is potentially significant in understanding the degradation and development of landforms in Tibetan landscape. (C) 2010 Elsevier Ltd and INQUA. All rights reserved. C1 [Wang, Liqiang; Yi, Chaolu] Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100085, Peoples R China. RP Yi, CL (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100085, Peoples R China. EM clyi@itpcas.ac.cn TC 2 Z9 2 PD MAY 1 PY 2011 VL 236 BP 65 EP 74 DI 10.1016/j.quaint.2010.06.003 UT WOS:000290511100008 DA 2023-03-23 ER PT J AU Zhao, Y Yu, ZC Zhao, WW AF Zhao, Yan Yu, Zicheng Zhao, Wenwei TI Holocene vegetation and climate histories in the eastern Tibetan Plateau: controls by insolation-driven temperature or monsoon-derived precipitation changes? SO QUATERNARY SCIENCE REVIEWS DT Article AB The climates on the eastern Tibetan Plateau are strongly influenced by direct insolation heating as well as monsoon-derived precipitation change. However, the moisture and temperature influences on regional vegetation and climate have not been well documented in paleoclimate studies. Here we present a well-dated and high-resolution loss-on-ignition, peat property and fossil pollen record over the last 10,000 years from a sedge-dominated fen peatland in the central Zoige Basin on the eastern Tibetan Plateau and discuss its ecological and climatic interpretations. Lithology results indicate that organic matter content is high at 60-80% between 10 and 3 ka (1 ka = 1000 cal yr BP) and shows large-magnitude fluctuations in the last 3000 years. Ash-free bulk density, as a proxy of peat decomposition and peatland surface moisture conditions, oscillates around a mean value of 0.1 g/cm(3), with low values at 6.5-4.7 ka, reflecting a wet interval, and an increasing trend from 4.7 to 2 ka, suggesting a drying trend. The time-averaged mean carbon accumulation rates are 30.6 gC/m(2)/yr for the last 10,000 years, higher than that from many northern peatlands. Tree pollen (mainly from Picea), mostly reflecting temperature change in this alpine meadow-forest ecotonal region, has variable values (from 3 to 34%) during the early Holocene, reaches the peak value during the mid-Holocene at 6.5 ka, and then decreases until 2 ka. The combined peat property and pollen data indicate that a warm and wet climate prevailed in the mid-Holocene (6.5-4.7 ka), representing a monsoon maximum or "optimum climate" for the region. The timing is consistent with recent paleo-monsoon records from southern China and with the idea that the interplays of summer insolation and other extratropical large-scale boundary conditions, including sea-surface temperature and sea-level change, control regional climate. The cooling and drying trend since the mid-Holocene likely reflects the decrease in insolation heating and weakening of summer monsoons. Regional synthesis of five pollen records along a south north transect indicates that this climate pattern can be recognized all across the eastern Tibetan Plateau. The peatland and vegetation changes in the late Holocene suggest complex and dramatic responses of these lowland and upland ecosystems to changes in temperature and moisture conditions and human activities. (C) 2011 Elsevier Ltd. All rights reserved. C1 [Zhao, Yan; Zhao, Wenwei] Lanzhou Univ, MOE Key Lab Western Chinas Environm Syst, Res Sch Arid Environm & Climate Change, Lanzhou 730000, Peoples R China. [Yu, Zicheng] Lehigh Univ, Dept Earth & Environm Sci, Bethlehem, PA 18015 USA. RP Zhao, Y (通讯作者)，Lanzhou Univ, MOE Key Lab Western Chinas Environm Syst, Res Sch Arid Environm & Climate Change, Lanzhou 730000, Peoples R China. EM yanzhao@lzu.edu.cn TC 177 Z9 208 PD MAY PY 2011 VL 30 IS 9-10 BP 1173 EP 1184 DI 10.1016/j.quascirev.2011.02.006 UT WOS:000291516100012 DA 2023-03-23 ER PT J AU Bian, JH Wu, Y Getz, LL Cao, YF Chen, F Yang, L AF Bian, Jiang-hui Wu, Yan Getz, Lowell L. Cao, Yi-Fan Chen, Fang Yang, Le TI Does maternal stress influence winter survival of offspring in root voles Microtus oeconomus? A field experiment SO OIKOS DT Article AB Maternal stress can have long-term adverse consequences on immunocompetence and disease risk of offspring, and winter survival is a crucial demographic parameter in the life-history of an individual that can substantially affect northern rodent population dynamics. An understanding of the effects of maternal stress on winter survival of offspring may help identify mechanisms driving population fluctuations of northern small mammals. Thus, we assessed the effects of maternal stress, resulting from high population densities, on winter survival of first generation (F-1) and second generation (F-2) in root voles Microtus oeconomus. Replicate high- and low-density enclosed parental populations were established, from which we obtained F-1 generation that were used to establish new enclosed, equal-density populations. The adults of the high-density parental populations had higher corticosterone levels, an indication of physiological stress, than did those of the low-density parental populations. Over-winter survival of the F-1 generation voles from the low-density parental populations was greater than that of those from the high-density parental populations. Over-winter survival of F-2 generation voles did not differ between the two treatments. Our results suggest that maternal stress affected over-winter survival of first generations but not second generations. Reduced immunocompetence, resulting from high population density stresses, transferred to offspring may be a factor in annual (winter) population declines. Because the effect is transitory, i.e. immunocompetence of F-2 voles is not affected, reduced immunocompetence resulting from high density stresses would not contribute to lengthy periods of low population densities that are characteristic of multi-annual population fluctuations. C1 [Bian, Jiang-hui; Cao, Yi-Fan; Yang, Le] Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, NW Inst Plateau Biol, CN-810001 Xining, Peoples R China. [Wu, Yan; Chen, Fang] Hangzhou Normal Univ, Sch Life & Environm Sci, CN-310012 Hangzhou, Zhejiang, Peoples R China. [Getz, Lowell L.] Univ Illinois, Dept Anim Biol, Urbana, IL 61801 USA. RP Bian, JH (通讯作者)，Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, NW Inst Plateau Biol, CN-810001 Xining, Peoples R China. EM bjh@nwipb.ac.cn TC 15 Z9 22 PD JAN PY 2011 VL 120 IS 1 BP 47 EP 56 DI 10.1111/j.1600-0706.2010.18165.x UT WOS:000285388800006 DA 2023-03-23 ER PT J AU Feng, YM Lu, Q Wu, B Liu, HX Wang, XQ Che, TT AF Feng, Yiming Lu, Qi Wu, Bo Liu, Hongxia Wang, Xuequang Che, Tengteng TI Land-use dynamics of an alpine-cold desertified area in the Qinhai-Tibetan Plateau in the last 30 years: a case study in Guinan County, Qinghai Province, China SO INTERNATIONAL JOURNAL OF SUSTAINABLE DEVELOPMENT AND WORLD ECOLOGY DT Article AB In this study, the land-use change characteristics in the past 30 years of an alpine-cold desertified area in the Qinhai-Tibetan Plateau were assessed by interpreting remote sensing satellite imagery during three key periods (1976, 1996, 2006) as well as by applying a geographical information system (GIS). The assessed results were summarized from three positions. First, grassland was the basic landscape background of study region, while, at the same time, many desert landscape elements (such as sandy land and drying ravines) were distributed among grasslands. Second, the disturbance derived from humans to the landscape was not intensive in the 1970s, but after 1996, such disturbance was greatly increased. Significant differences in dominance index were found among different patch types, and landscape fragmentation degree and simple landscape diversification were low in 1976. After 1996, there was an obvious change in the pattern of patches and the landscape became more fragmented. Third, in the last 30 years, transformation speeds among different lands-use types accelerated. During 1976-1996, great changes in land-use area occurred, but the speed of change was slow. During 1996-2006, the land-use area change was less than that for 1976-1996, but the speed of change was rapid. The main driving force contributing to the dynamic changes of land use was human activities. C1 [Feng, Yiming; Lu, Qi; Wu, Bo; Wang, Xuequang; Che, Tengteng] CAF, Inst Desertificat Studies, Beijing 100091, Peoples R China. [Liu, Hongxia] Chinese Acad Agr Sci, Agr Informat Inst, Beijing 100081, Peoples R China. RP Lu, Q (通讯作者)，CAF, Inst Desertificat Studies, Beijing 100091, Peoples R China. EM luqi@caf.ac.cn TC 8 Z9 8 PY 2011 VL 18 IS 4 BP 357 EP 365 DI 10.1080/13504509.2011.562004 UT WOS:000293071500009 DA 2023-03-23 ER PT J AU Gao, YH Zeng, XY Schumann, M Chen, H AF Gao, Yongheng Zeng, Xiaoyang Schumann, Martin Chen, Huai TI Effectiveness of Exclosures on Restoration of Degraded Alpine Meadow in the Eastern Tibetan Plateau SO ARID LAND RESEARCH AND MANAGEMENT DT Article AB Restoration of degraded alpine meadow caused by overgrazing is directly related to land sustainable and economical development in the Tibetan Plateau. The objective of this study was to evaluate changes in vegetation and soil characteristics in areas under overgrazing and exclosed for 5 to 10 years for grazing in a degraded alpine meadow on the eastern Tibetan Plateau. Results showed that excluding livestock grazing resulted in significant increases in vegetation coverage and plant biomass by enhancing development of perennial grasses and sedges. Soil organic carbon and total nitrogen in the 0-10 cm soil layer increased significantly with increasing exclosure time. Soil clay and water contents were higher in the exclosed sites than in the grazed site. The results suggested that the degraded alpine meadow due to overgrazing in this region can be reversed and significant increases in soil fertility, vegetation diversity, cover, and biomass can be achieved by implementing adequate protecting practices. C1 [Gao, Yongheng; Zeng, Xiaoyang] Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolut & Regulat, POB 417, Chengdu 610041, Sichuan Prov, Peoples R China. [Chen, Huai] Univ Quebec, Inst Environm Sci, Montreal, PQ H3C 3P8, Canada. [Schumann, Martin] Ernst Moritz Arndt Univ Greifswald, Inst Bot & Landscape Ecol, Greifswald, Germany. RP Gao, YH (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Key Lab Mt Environm Evolut & Regulat, POB 417, Chengdu 610041, Sichuan Prov, Peoples R China. EM yhgao@imde.ac.cn TC 24 Z9 29 PY 2011 VL 25 IS 2 BP 164 EP 175 DI 10.1080/15324982.2011.554954 UT WOS:000289078500005 DA 2023-03-23 ER PT J AU Li, W Huang, HZ Zhang, ZN Wu, GL AF Li, W. Huang, H. -Z. Zhang, Z. -N. Wu, G. -L. TI Effects of grazing on the soil properties and C and N storage in relation to biomass allocation in an alpine meadow SO JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION DT Article AB Livestock grazing is one of the most important factors influencing the above-ground community composition and structure in a natural grassland ecosystem. Different grazing intensities also have the potential to alter soil C and N storage substantially in grasslands. We conducted a field community study and soil analyses to determine the effects of different grazing intensities on the above-ground community and soil properties in an alpine meadow on the Tibetan Plateau. Our results showed the following: (i) the vegetation height, coverage, and above-ground biomass significantly declined with increased grazing intensity, but the species richness reached the highest level in a moderate grazing intensity meadow; (ii) grazing had a significant positive effect on soil properties in that the soil moisture content, soil organic carbon concentration, soil total nitrogen concentration, soil available nitrogen, soil total phosphorus, and soil available phosphorus significantly increased with increased grazing pressure; and (iii) soil C and N storage also significantly increased with increased grazing pressure; altogether, these increases had a significant positive correlation with the increase of below-ground biomass allocation. Our results indicated that higher grazing intensity might have a potentially positive effect to increase the soil C and N storage in alpine meadows. However, from a long-term perspective, moderate grazing may help to achieve a balance between species diversity protection, livestock production and soil C and N management. C1 [Li, W.; Huang, H. -Z.; Zhang, Z. -N.; Wu, G. -L.] NW A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Li, W.; Wu, G. -L.] Chinese Acad Sci, Inst Soil & Water Conservat, Yangling 712100, Shaanxi, Peoples R China. [Li, W.; Wu, G. -L.] MWR, Yangling 712100, Shaanxi, Peoples R China. [Wu, G. -L.] Lanzhou Univ, MOE Key Lab Arid & Grassland Ecol, Lanzhou 730000, Peoples R China. RP Wu, GL (通讯作者)，NW A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. EM gaolinwu@gmail.com TC 66 Z9 78 PY 2011 VL 11 IS 4 BP 27 EP 39 DI 10.4067/S0718-95162011000400003 UT WOS:000299377100003 DA 2023-03-23 ER PT J AU Zhang, FW Li, YN Gao, GM Wang, SP Zhao, XQ Du, MY Wang, QX AF Zhang, Fa-Wei Li, Ying-Nian Gao, Guang-Min Wang, Shi-Ping Zhao, Xin-Quan Du, Ming-Yuan Wang, Qin-Xue TI RESPONSE OF ALPINE PLANT COMMUNITY TO SIMULATED CLIMATE CHANGE: TWO-YEAR RESULTS OF RECIPROCAL TRANSLOCATION EXPERIMENT (TIBETAN PLATEAU) SO POLISH JOURNAL OF ECOLOGY DT Article AB The great sensitivity of the response of alpine plant community to climate change makes the identification of these responses important. In 2007, we conducted a reciprocal translocation experiment on 100 x 100 x 40 cm coherent turf and soil along an elevation gradient of 3200-3800 m on the south slope of Qilian Mountains northeast of the Qinghai-Tibetan Plateau. The aim was to understand the warming/cooling effects on the alpine ecosystem where treatments were simulated by donor elevations below/above receptors. Translocated vegetation comprised the Kobresia meadow at 3200 m, deciduous shrub meadow at 3400 m, forbs meadow at 3600 m, and sparse vegetation at 3800 m. The 5 x 5 cm grid method (50 x 50 cm, 100 grids) was used for surveying plant species absolute abundance in translocated quadrats. Results showed that species richness and Shannon-Weaver index of Kobresia meadow increased significantly (P <0.05) when translocated to 3400 m. Shannon-Weaver index of shrub meadow declined, while shrub species abundance responded slightly both to warming and cooling treatments. Both species richness and Shannon-Weaver index of forbs meadow and sparse vegetation were enhanced evidently at 3200 m and 3400 m. Four groups were identified by non-metric multidimensional scaling based on receptor elevation. Responses of the alpine plant community and the function group appeared to be specific to climate magnitude and specific to function type, respectively. Correlation indicated that climatic factors played a much more important role than soil in the response of the alpine plant community. Four vegetation types were sensitive to climate change, while Kobresia meadow behaved flexibly. Global warming would depress sedges but favor legumes and graminoids. C1 [Zhang, Fa-Wei] China Meteorol Adm, Inst Plateau Meteorol, Chengdu 610071, Sichuan, Peoples R China. [Zhang, Fa-Wei; Li, Ying-Nian; Gao, Guang-Min; Zhao, Xin-Quan] Chinese Acad Sci, NW Inst Plateau Biol, Xining 810001, Qinghai, Peoples R China. [Wang, Shi-Ping] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100085, Peoples R China. [Du, Ming-Yuan] Natl Inst Agroenvironm Sci, Tsukuba, Ibaraki 3058604, Japan. [Wang, Qin-Xue] Natl Inst Environm Studies, Tsukuba, Ibaraki 3050053, Japan. RP Zhang, FW (通讯作者)，China Meteorol Adm, Inst Plateau Meteorol, Chengdu 610071, Sichuan, Peoples R China. EM fwzhang@nwipb.cas.cn TC 6 Z9 7 PY 2011 VL 59 IS 4 BP 741 EP 751 UT WOS:000298457300009 DA 2023-03-23 ER PT J AU Zhang, RY Gou, X Bai, Y Zhao, J Chen, LY Song, XY Wang, G AF Zhang, Renyi Gou, Xin Bai, Yan Zhao, Jun Chen, Lingyun Song, Xiaoyu Wang, Gang TI BIOMASS FRACTION OF GRAMINOIDS AND FORBS IN N-LIMITED ALPINE GRASSLAND: N:P STOICHIOMETRY SO POLISH JOURNAL OF ECOLOGY DT Article AB It is known that the dominance of graminoid species is promoted by N addition; however, there has been relatively little effort to examine the pattern induced by natural N fertility. Since nutrient use efficiency (NUE) is an important trait determining plant competitive ability, we expected that the species guild with higher NUE (lower nutrient content) may be more competitive on infertile soils. We explored the relationships between relative forbs biomass share, soil N and productivity by the linear regression analysis on a natural alpine meadow in northeast of Qinghai-Tibetan Plateau (3600 m a.s.l.). To test the variety of leaf N:P stoichiometry, paired t test and general linear model multivariate (GLM) analysis were also used. We found that the leaf N:P ratios of the whole community were below 13 in studied sites, which may be consistent with the N limitation on the vegetation. Graminoids retained lower concentrations of leaf N and P than forbs in community on the N-limited grassland. Consistent with our prediction, we found that the biomass fraction of graminoids declined with soil N content and aboveground production on the grassland. Different from the pattern along fertility gradients induced by N fertilization, our results showed that graminoids with lower internal nutrient content were able to resist low levels of nutrient availability on the natural alpine grassland when compared to forbs. C1 [Zhang, Renyi; Gou, Xin; Bai, Yan; Zhao, Jun; Chen, Lingyun; Song, Xiaoyu; Wang, Gang] Lanzhou Univ, Minist Educ, Key Lab Arid & Grassland Agroecol, Lanzhou 730000, Peoples R China. RP Wang, G (通讯作者)，Lanzhou Univ, Minist Educ, Key Lab Arid & Grassland Agroecol, Lanzhou 730000, Peoples R China. EM wgmg36@lzu.edu.cn TC 10 Z9 15 PY 2011 VL 59 IS 1 BP 105 EP 114 UT WOS:000288927700010 DA 2023-03-23 ER PT J AU Ding, XZ Long, RJ Kreuzer, M Mi, JD Yang, B AF Ding, X. Z. Long, R. J. Kreuzer, M. Mi, J. D. Yang, B. TI Methane emissions from yak (Bos grunniens) steers grazing or kept indoors and fed diets with varying forage concentrate ratio during the cold season on the Qinghai-Tibetan Plateau SO ANIMAL FEED SCIENCE AND TECHNOLOGY DT Article AB For national greenhouse gas inventories exact data on all major domesticated livestock systems are required Such data is completely lacking for yak (Bos grunniens) and as this ruminant livestock species seems to have digestion and metabolism which differs from cattle making data extrapolations from cattle are potentially inaccurate In the present study methane (CH4) emissions from yak were estimated under grazing and indoor feeding conditions in the cold season on the Qinghai-Tibetan Plateau at >3200m above sea level Twelve 3 year old growing yak steers (175 +/- 10 7 kg) were subjected to measurements of CH4 output using the sulfur hexafluoride tracer gas technique nutrient intake and apparent digestibilities The first group of three yaks grazed on native winter alpine meadows while the indoor groups were fed either oat hay or total mixed diets of oat hay and concentrate in ratios of 0 6 04 and 04 06 respectively on a dry matter (DM) basis The experimental period lasted for 6 weeks with the first 5 weeks for adaptation and the last for measurement The oat hay contained slightly more crude protein (CP) and less fiber compared to the winter pasture grass while inclusion of concentrate increased the CP intake of the yaks considerably Yaks fed indoors gained body weight (BW) during the experimental period (about 200 g/day and slightly higher with concentrate) while grazing yaks lost 550 g/day of BW Daily CH4 emissions of the grazing yaks were 81 4 g/day or 1 68 g/kg BW0 75 at an estimated daily grass DM intake of 3 78 kg Absolute levels of CH4 emissions were slightly higher in the oat hay fed yaks Compared to the oat hay treatment CH4 production declined by 03 and 04 with forage concentrate ratios of 6 04 and 04 06 respectively Overall the average proportion of gross energy lost as CH4 energy (kJ/MJ) was 54 +/- 15 2 These values are the CH4 emission factors (according to Tier 1 of IPCC 2006) of about 28 kg/year for grazing non-lactating yaks weighing 175 kg When adjusted to metabolic BW yaks were at the lower range of CH4 emission compared to cattle while they were average when CH4 was related to DM and gross energy intake Implementing proper grazing management practices to improve winter diet quality and quantity and thus animal productivity can be expected to substantially mitigate CH4 emissions per unit of meat and milk produced by yak (C) 2010 Elsevier BV All rights reserved C1 [Ding, X. Z.; Long, R. J.; Mi, J. D.] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, Lanzhou 730000, Peoples R China. [Ding, X. Z.] Chinese Acad Sci, NW Inst Plateau Biol, Xining, Peoples R China. [Long, R. J.] Lanzhou Univ, Sch Pastoral Agr & Technol, Lanzhou 730000, Peoples R China. [Kreuzer, M.] ETH, Inst Plant Anim & Agroecosytem Sci, CH-8092 Zurich, Switzerland. [Yang, B.] Gansu Agr Univ, Coll Anim Sci & Technol, Lanzhou, Peoples R China. RP Long, RJ (通讯作者)，Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, Lanzhou 730000, Peoples R China. TC 36 Z9 41 PD DEC 22 PY 2010 VL 162 IS 3-4 BP 91 EP 98 DI 10.1016/j.anifeedsci.2010.09.007 UT WOS:000285672500003 DA 2023-03-23 ER PT J AU Dong, SK Li, JP Li, XY Wen, L Zhu, L Li, YY Ma, YS Shi, JJ Dong, QM Wang, YL AF Dong, S. K. Li, J. P. Li, X. Y. Wen, L. Zhu, L. Li, Y. Y. Ma, Y. S. Shi, J. J. Dong, Q. M. Wang, Y. L. TI Application of design theory for restoring the "black beach" degraded rangeland at the headwater areas of the Qinghai-Tibetan Plateau SO AFRICAN JOURNAL OF AGRICULTURAL RESEARCH DT Review AB Severe degradation of alpine rangeland into the "black beach" at the headwater areas of the Qinghai-Tibetan Plateau driven by human disturbance and climatic change is limiting the sustainable development of ecological, social and economic systems in both local and downstream regions. Appropriate restoration theory is needed to guide the technical and managerial strategies to restore the degraded alpine rangeland and maintain the upstream-downstream relationships in the ecological web. A ten-year research program of restoring the "black-beach" degraded rangelands at the headwater areas of the Qinghai-Tibetan Plateau was summarized in this study to clarify the restoration theory guiding the interventions for rehabilitating these rangelands and provide some examples of successful rehabilitations for worldwide alpine rangeland ecosystems. It was found that the design theory was more applicable than the self-design theory in guiding the restoration interventions for "black-beach" degraded rangeland. Replanting guided by the design theory was effective in reconstructing the alpine rangeland vegetation and improving the ecological and economic values of the alpine rangeland ecosystem at the headwater areas of the Qinghai-Tibetan Plateau. Seed rain, seed bank and seedling germination should be included in post-restoration monitoring and assessment of restoration practices. C1 [Dong, S. K.; Li, J. P.; Li, X. Y.; Wen, L.; Zhu, L.; Li, Y. Y.] Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. [Ma, Y. S.; Shi, J. J.; Dong, Q. M.; Wang, Y. L.] Qinghai Acad Anim Sci & Vet Med, Xining 810003, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 62 Z9 71 PD DEC PY 2010 VL 5 IS 25 BP 3542 EP 3552 UT WOS:000286634600004 DA 2023-03-23 ER PT J AU Yu, Z Wang, GX Wang, YB AF Zhang Yu Wang Genxu Wang Yibo TI Response of biomass spatial pattern of alpine vegetation to climate change in permafrost region of the Qinghai-Tibet Plateau, China SO JOURNAL OF MOUNTAIN SCIENCE DT Article AB Alpine ecosystems in permafrost region are extremely sensitive to climate changes. To determine spatial pattern variations in alpine meadow and alpine steppe biomass dynamics in the permafrost region of the Qinghai-Tibet Plateau, China, calibrated with historical datasets of above-ground biomass production within the permafrost region's two main ecosystems, an ecosystem-biomass model was developed by employing empirical spatialdistribution models of the study region's precipitation, air temperature and soil temperature. This model was then successfully used to simulate the spatio-temporal variations in annual alpine ecosystem biomass production under climate change. For a 0.44A degrees C decade-1 rise in air temperature, the model predicted that the biomasses of alpine meadow and alpine steppe remained roughly the same if annual precipitation increased by 8 mm per decade(-1), but the biomasses were decreased by 2.7% and 2.4%, respectively if precipitation was constant. For a 2.2A degrees C decade(-1) rise in air temperature coupled with a 12 mm decade(-1) rise in precipitation, the model predicted that the biomass of alpine meadow was unchanged or slightly increased, while that of alpine steppe was increased by 5.2%. However, in the absence of any rise in precipitation, the model predicted 6.8% and 4.6% declines in alpine meadow and alpine steppe biomasses, respectively. The response of alpine steppe biomass to the rising air temperatures and precipitation was significantly lesser and greater, respectively than that of alpine meadow biomass. A better understanding of the difference in alpine ecosystem biomass production under climate change is greatly significant with respect to the influence of climate change on the carbon and water cycles in the permafrost regions of the Qinghai-Tibet Plateau. C1 [Wang Genxu] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Zhang Yu; Wang Yibo] Lanzhou Univ, Coll Resources & Environm, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM wanggx@imde.ac.cn TC 20 Z9 21 PD DEC PY 2010 VL 7 IS 4 BP 301 EP 314 DI 10.1007/s11629-010-2011-5 UT WOS:000284074700001 DA 2023-03-23 ER PT J AU Peng, SS Piao, SL Ciais, P Fang, JY Wang, XH AF Peng, Shushi Piao, Shilong Ciais, Philippe Fang, Jingyun Wang, Xuhui TI Change in winter snow depth and its impacts on vegetation in China SO GLOBAL CHANGE BIOLOGY DT Article AB Snow on land is an important component of the global climate system, but our knowledge about the effects of its changes on vegetation are limited, particularly in temperate regions. In this study, we use daily snow depth data from 279 meteorological stations across China to investigate the distribution of winter snow depth (December-February) from 1980 to 2005 and its impact on vegetation growth, here approximated by satellite-derived vegetation greenness index observations [Normalized Difference Vegetation Index (NDVI)]. The snow depth trends show strong geographical heterogeneities. An increasing trend (> 0.01 cm yr-1) in maximum and mean winter snow depth is found north of 40 degrees N (e.g. Northeast China, Inner Mongolia, and Northwest China). A declining trend (<-0.01 cm yr-1) is observed south of 40 degrees N, particularly over Central and East China. The effect of changes in snow depth on vegetation growth was examined for several ecosystem types. In deserts, mean winter snow depth is significantly and positively correlated with NDVI during both early (May and June) and mid-growing seasons (July and August), suggesting that winter snow plays a critical role in regulating desert vegetation growth, most likely through persistent effects on soil moisture. In grasslands, there is also a significant positive correlation between winter snow depth and NDVI in the period May-June. However, in forests, shrublands, and alpine meadow and tundra, no such correlation is found. These ecosystem-specific responses of vegetation growth to winter snow depth may be due to differences in growing environmental conditions such as temperature and rainfall. C1 [Peng, Shushi; Piao, Shilong; Fang, Jingyun; Wang, Xuhui] Peking Univ, Dept Ecol, Coll Urban & Environm Sci, Key Lab Earth Surface Proc,Minist Educ, Beijing 100871, Peoples R China. [Ciais, Philippe] CEA, Lab Sci Climat & Environm, CNRS UVSQ, F-91191 Gif Sur Yvette, France. RP Piao, SL (通讯作者)，Peking Univ, Dept Ecol, Coll Urban & Environm Sci, Key Lab Earth Surface Proc,Minist Educ, Beijing 100871, Peoples R China. EM slpiao@pku.edu.cn TC 135 Z9 144 PD NOV PY 2010 VL 16 IS 11 BP 3004 EP 3013 DI 10.1111/j.1365-2486.2010.02210.x UT WOS:000282375700008 DA 2023-03-23 ER PT J AU Wang, GX Liu, LA Liu, GS Hu, HC Li, TB AF Wang, Genxu Liu, Lin'an Liu, Guangsheng Hu, Hongchang Li, Taibin TI Impacts of Grassland Vegetation Cover on the Active-Layer Thermal Regime, Northeast Qinghai-Tibet Plateau, China SO PERMAFROST AND PERIGLACIAL PROCESSES DT Article AB The impact of vegetation cover on the active-layer thermal regime was examined in an alpine meadow located in the permafrost region of Qinghai-Tibet over a three-year period. A high vegetation cover (93%) delayed thawing and freezing at a given depth relative to sites with lower covers (65%, 30% and 5%). Low vegetation covers exhibited greater annual variability in soil temperatures, and may be more sensitive to changes in air temperature. Low vegetation covers are also linked to higher thermal diffusivity and thermal conductivity in the soils. The maintenance of a high vegetation cover on alpine meadows reduces the impact of heat cycling on the permafrost, may minimise the impact of climate change and helps preserve the microenvironment of the soil. Copyright (C) 2010 John Wiley & Sons, Ltd. C1 [Wang, Genxu; Liu, Lin'an; Liu, Guangsheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Wang, Genxu; Hu, Hongchang; Li, Taibin] Lanzhou Univ, Coll Resources & Environm, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM gxwang@ns.lzb.ac.cn TC 22 Z9 33 PD OCT-DEC PY 2010 VL 21 IS 4 BP 335 EP 344 DI 10.1002/ppp.699 UT WOS:000285846900005 DA 2023-03-23 ER PT J AU Wu, GL Liu, ZH Zhang, L Hu, TM Chen, JM AF Wu, Gao-Lin Liu, Zhen-Heng Zhang, Lei Hu, Tian-Ming Chen, Ji-Min TI Effects of artificial grassland establishment on soil nutrients and carbon properties in a black-soil-type degraded grassland SO PLANT AND SOIL DT Article AB Disturbance and management approaches can contribute significantly to restoration of degraded grassland ecosystems. This study has examined the re-establishment of artificial grassland to renew extremely degraded black-soils in an alpine area of the Qinghai-Tibetan Plateau, in China. We evaluated this method for which grassland ecosystem responses to this restoration approach are needed. Here, we evaluated the response of aboveground plant communities and belowground soil nutrient and soil carbon storage to the establishment of artificial grassland in grasslands on black-soils in the eastern Qinghai-Tibetan Plateau. Three grasslands sites were selected: a degraded grassland on an original black-soil, and 3- and 6-year-old Elymus nutans artificial grasslands. Artificial grassland establishment significantly improved aboveground biomass, but also significantly decreased species richness, diversity and evenness for black-soil-type degraded grassland. Artificial grassland establishment resulted in significantly improved soil total nitrogen and phosphorus, and decreased soil organic matter, available nitrogen, and phosphorus, especially in the depth of 20-30 cm soil layer. Although artificial grassland establishment significantly improved soil organic carbon in the topsoil (0-10 cm), it decreased at depths of 10-20 and 20-30 cm. Six-year artificial grassland significantly increased soil carbon storage compared with black-soil-type degraded grasslands. Accordingly, artificial grassland can be used as effective restoration and rehabilitation approach to improve productivity and regulate community and soil properties in black-soil-type degraded grasslands. Our results suggest that ecosystem functions such as production of aboveground biomass, the provision of soil surface cover, and nutrient accumulation may be provided by artificial grassland. However, more time is needed for plant diversity and soil carbon storage functions to recover fully from degradation. C1 [Wu, Gao-Lin; Hu, Tian-Ming; Chen, Ji-Min] NW A&F Univ, Coll Anim Sci & Technol, Yangling 712100, Shaanxi, Peoples R China. [Wu, Gao-Lin; Zhang, Lei; Chen, Ji-Min] NW A&F Univ, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. [Liu, Zhen-Heng] Maqu Alpine Grassland Workstn, Maqu 747300, Gansu, Peoples R China. [Wu, Gao-Lin; Chen, Ji-Min] Inst Soil & Water Conservat CAS&MWR, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China. RP Hu, TM (通讯作者)，NW A&F Univ, Coll Anim Sci & Technol, Yangling 712100, Shaanxi, Peoples R China. EM gaolinwu@gmail.com; hutianming@126.com; gyzcjm@ms.iswc.ac.cn TC 80 Z9 107 PD AUG PY 2010 VL 333 IS 1-2 BP 469 EP 479 DI 10.1007/s11104-010-0363-9 UT WOS:000280089400037 DA 2023-03-23 ER PT J AU Yu, L Zhou, L Liu, W Zhou, HK AF Yu Long Zhou Li Liu Wei Zhou Hua-Kun TI Using Remote Sensing and GIS Technologies to Estimate Grass Yield and Livestock Carrying Capacity of Alpine Grasslands in Golog Prefecture, China SO PEDOSPHERE DT Article AB Remote sensing data from the Terra Moderate-Resolution Imaging Spectroradiometer (MODIS) and geospatial data were used to estimate grass yield and livestock carrying capacity in the Tibetan Autonomous Prefecture of Golog, Qinghai, China. The MODIS-derived normalized difference vegetation index (MODIS-NDVI) data were correlated with the aboveground green biomass (AGGB) data from the aboveground harvest method. Regional regression model between the MODIS-NDVI and the common logarithm (LOG10) of the AGGB was significant (r(2) = 0.51, P < 0.001), it was, therefore, used to calculate the maximum carrying capacity in sheep-unit year per hectare. The maximum livestock carrying capacity was then adjusted to the theoretical livestock carrying capacity by the reduction factors (slope, distance to water, and soil erosion). Results indicated that the grassland conditions became worse, with lower aboveground palatable grass yield, plant height, and cover compared with the results obtained in 1981. At the same time, although the actual livestock numbers decreased, they still exceeded the proper theoretical livestock carrying capacity, and overgrazing rates ranged from 27.27% in Darlag County to 293.99% in Baima County. Integrating remote sensing and geographical information system technologies, the spatial and temporal conditions of the alpine grassland, trend, and projected stocking rates could be forecasted for decision making. C1 [Yu Long; Zhou Li; Liu Wei; Zhou Hua-Kun] Chinese Acad Sci, NW Inst Plateau Biol, Xining 810001, Peoples R China. [Yu Long] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. RP Yu, L (通讯作者)，Chinese Acad Sci, NW Inst Plateau Biol, Xining 810001, Peoples R China. EM yuhulong@yahoo.com.cn TC 55 Z9 77 PD JUN PY 2010 VL 20 IS 3 BP 342 EP 351 DI 10.1016/S1002-0160(10)60023-9 UT WOS:000279186500009 DA 2023-03-23 ER PT J AU Wang, JF Wang, GX Hu, HC Wu, QB AF Wang, Junfeng Wang, Genxu Hu, Hongchang Wu, Qingbai TI The influence of degradation of the swamp and alpine meadows on CH4 and CO2 fluxes on the Qinghai-Tibetan Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB CH4 and CO2 fluxes from a high-cold swamp meadow and an alpine meadow on the Qinghai- Tibetan Plateau, subject to different degrees of degradation, were measured over a 12-month period. Air temperature, soil temperature and moisture, and the depths of the water table and thawing-freezing layer were determined. For swamp meadows, the greater the degradation, the lesser the carbon efflux. CH4 emissions at the nondegraded swamp meadow site were 1.09-3.5 and 2.5-11.27 times greater, and CO2 emissions 1.08-1.69 and 1.41-4.43 times greater, respectively, than those from moderately and severely degraded sites. For alpine meadows, the greater the degradation, the greater the CH4 consumption and CO2 emissions. CH4 consumption at the severely degraded alpine meadow site was 6.6-21 and 1.1-5.25 times greater, and CO2 emissions 1.05-78.5 and 1.04-6.28 times greater, respectively, than those from the nondegraded and moderately degraded sites. The CH4 and CO2 fluxes at both sites were significantly correlated (R-2 > 0.59, P < 0.05) with air temperature, soil temperature, and topsoil (0-5 cm depth) moisture, indicating these to be the main environmental factors affecting such fluxes. C1 [Wang, Junfeng; Wu, Qingbai] Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. [Wang, Genxu] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Wang, Genxu; Hu, Hongchang] Lanzhou Univ, Coll Resources & Environm Sci, Lanzhou 730000, Peoples R China. RP Wang, JF (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soil Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. EM wangjf2008@yahoo.com.cn TC 33 Z9 41 PD APR PY 2010 VL 60 IS 3 BP 537 EP 548 DI 10.1007/s12665-009-0193-3 UT WOS:000276637100008 DA 2023-03-23 ER PT J AU Ren, W Tan, HC Wu, J Deng, YC Wu, YB Tang, YH Cui, XY AF Ren, Wei Tan, Hongchao Wu, Jing Deng, Yongcui Wu, Yibo Tang, Yanhong Cui, Xiaoyong TI UV light spectral response of photosynthetic photochemical efficiency in alpine mosses SO JOURNAL OF PLANT ECOLOGY DT Article AB Aims Bryophytes play an important role in primary production in harsh alpine environment As other alpine plants, the alpine bryophytes are often exposed to stronger UV radiation than lowland plants Plants growing under high UV radiation may differ from those from low UV regimes In their physiological response to UV radiation We were to (I) test the hypothesis and to address whether and/or how alpine bryophytes differ in photosynthetic photochemical characteristics in response to UV light and (II) understand the potential effects of UV radiation on photosynthetic photochemical process in alpine bryophytes Methods We examined the maximum quantum efficiency of photosystem II (PSII) photochemistry (F root F-m) for two alpine bryophyte species, Distichium inclinatum and Encalypta alpine, from a Kobresia humilis meadow and a Kobresia tibetica wetland, respectively, in Haibei, Qinghai (37 degrees 29'N, 101 degrees 12'E, altitude 3 250 ml), and for a lowland bryophyte, Polytrichum juniperinum, under different spectrum of UV light Biological spectral weighting function (BSWF) was obtained to evaluate the effect of UV light on the physiological response in these species Important Findings 1) The maximum quantum efficiency of photosystem II photochemistry (F root F-m) declined linearly with the increase of radiation dose in wavelenghts from 250 to 420 nm. The effect of UV radiation on F root F-m decreased with higher rate from 250 to 320 nm an from 400 to 420 nm than in UVA range 2) The three species from different ecosystems contrasting in altitudes showed similar pattern of UV effectiveness In comparison with other species reported so far, the moss BSWF was among those with the most modest decrease trend with spectrum effect of UV light 50 times higher at 250 than at 420 nm 3) Under the scenario of 16% reduction of stratospheric ozone, the integrated effectiveness from 290 to 345 nm increased only 5%, suggesting that the photochemical activity of the bryophyte PSII is likely to insensitive to O-3 depletion C1 [Ren, Wei; Tan, Hongchao; Wu, Jing; Deng, Yongcui; Wu, Yibo; Cui, Xiaoyong] Chinese Acad Sci, Grad Univ, Coll Resources & Environm, Beijing 100049, Peoples R China. [Tang, Yanhong] Natl Inst Environm Studies, Tsukuba, Ibaraki 3050053, Japan. RP Cui, XY (通讯作者)，Chinese Acad Sci, Grad Univ, Coll Resources & Environm, Beijing 100049, Peoples R China. TC 7 Z9 8 PD MAR PY 2010 VL 3 IS 1 SI SI BP 17 EP 24 DI 10.1093/jpe/rtp029 UT WOS:000275660300003 DA 2023-03-23 ER PT J AU Zhang, F Wang, T Xue, X Han, BS Peng, F You, QG AF Zhang, Fang Wang, Tao Xue, Xian Han, Bangshuai Peng, Fei You, Quangang TI The response of soil CO2 efflux to desertification on alpine meadow in the Qinghai-Tibet Plateau SO ENVIRONMENTAL EARTH SCIENCES DT Article AB Assessing the global C budget requires a better understanding of the effect of environmental factors on soil CO2 efflux from both experiments and theoretical research, especially in different desertified lands in the Qinghai-Tibet Plateau. Based on the enclosed chamber method, soil CO2 efflux in four different desertified lands and one control [alpine meadow (AM)] were measured in June, August and September, 2008, respectively. Soil CO2 efflux rates at the top, the middle, the bottom of a slope and the flat in front of the slope were obtained at Maduo County. The results showed that average daily soil CO2 efflux rates were 3.72, 2.65, 2.68, 0.59 and 0.37 g m(-2) day(-1) in the AM, lightly (LDL), moderately (MDL), severely (SDL) and very severely desertified lands (VSDL) during the growing season, respectively. Soil CO2 efflux decreased with the change of desertification. The response of soil CO2 efflux to environmental factors was adequately described by the linear model; models accounted for 76, 65, 72, 59 and 71% of the variability on soil CO2 efflux in the AM, LDL, MDL, SDL and VSDL, respectively. Any environmental factor, however, was insufficient to explain the soil CO2 efflux; the common influence could perfectly reflect soil CO2 efflux response to the desertification change. C1 [Zhang, Fang; Wang, Tao; Xue, Xian; Peng, Fei; You, Quangang] Chinese Acad Sci, Key Lab Desert & Desertificat, Inst Cold & Arid Reg Environm & Engn Res, Lanzhou 730000, Peoples R China. [Han, Bangshuai] SUNY Syracuse, Coll Environm Sci & Forestry, Syracuse, NY 13210 USA. RP Wang, T (通讯作者)，Chinese Acad Sci, Key Lab Desert & Desertificat, Inst Cold & Arid Reg Environm & Engn Res, 320 Donggang W Rd, Lanzhou 730000, Peoples R China. EM zhangfang2003_2006@163.com; wangtao@lzb.ac.cn TC 12 Z9 13 PD MAR PY 2010 VL 60 IS 2 BP 349 EP 358 DI 10.1007/s12665-009-0421-x UT WOS:000276637000013 DA 2023-03-23 ER PT J AU Shi, XM Li, XG Long, RJ Singh, BP Li, ZT Li, FM AF Shi, Xiao Ming Li, Xiao Gang Long, Rui Jun Singh, Bhupinder Pal Li, Zhuo Ting Li, Feng Min TI Dynamics of soil organic carbon and nitrogen associated with physically separated fractions in a grassland-cultivation sequence in the Qinghai-Tibetan plateau SO BIOLOGY AND FERTILITY OF SOILS DT Article AB This study is aimed at quantifying organic carbon (C) and total nitrogen (N) dynamics associated with physically separated soil fractions in a grassland-cultivation sequence in the Qinghai-Tibetan plateau. Concentrations of organic C and N of soil, free and occluded particulate organic matter (OM), and aggregate- and mineral-associated OM in different land uses are increased in the following order: 50 years cultivation < 12 years cultivation a parts per thousand currency signaEuro parts per thousand native grassland. The prolonged cropping of up to 50 years markedly affected the concentrations of free and occluded particulate OM and mineral-associated OM. After wet-sieving, 43% of native grassland soil mass was found in > 1-10 mm water-stable aggregates that stored 40% of bulk soil organic C and N; only 16% and 7% of soil mass containing 16% and 7% of bulk soil organic C and N was > 1-10 mm water-stable aggregates of soils cultivated for 12 years and 50 years, respectively. This indicated that losses of soil organic C and N following cultivation of native grassland would be largely related to disruption of > 1-10 mm size aggregates and exposure of intra-aggregate OM to microbial attack. Organic C and N concentrations of soil aggregates were similar among aggregate size fractions (> 0.05-10 mm) within each land use, suggesting that soil aggregation process of these soils did not follow the hierarchy model. The increase of the C-to-N ratio of free and occluded particulate fractions in the cultivated soils compared to the grassland soil indicated a greater loss of N than C. C1 [Shi, Xiao Ming; Li, Xiao Gang; Long, Rui Jun; Li, Zhuo Ting; Li, Feng Min] Lanzhou Univ, MOE Key Lab Arid & Grassland Ecol, Sch Life Sci, Lanzhou 730000, Peoples R China. [Singh, Bhupinder Pal] Ind & Investment NSW, Forest Sci Ctr, Beecroft, NSW 2119, Australia. RP Li, XG (通讯作者)，Lanzhou Univ, MOE Key Lab Arid & Grassland Ecol, Sch Life Sci, Lanzhou 730000, Peoples R China. EM lixg2002@hotmail.com TC 31 Z9 38 PD FEB PY 2010 VL 46 IS 2 BP 103 EP 111 DI 10.1007/s00374-009-0414-7 UT WOS:000273555100003 DA 2023-03-23 ER PT J AU Harris, RB AF Harris, R. B. TI Rangeland degradation on the Qinghai-Tibetan plateau: A review of the evidence of its magnitude and causes SO JOURNAL OF ARID ENVIRONMENTS DT Review AB Rangelands of the Qinghai-Tibetan plateau (QTP), although sparsely populated and contributing little to China's overall economy, play an important environmental role throughout Asia. They contain high biodiversity values and can also potentially provide China with a source of cultural and geographic variety in the future. Chinese government reports paint a gloomy picture, considering vast portions of the QTP degraded and blaming irrational overstocking of livestock as the principal culprit. Global climate change, population increases, and "rodent" damage are also invoked as causes of rangeland degradation. In contrast, some Western observers claim that traditional pastoral practices were sustainable, and identify either previous or more recent state policies as the cause of degradation. Chinese governments at national and provincial levels have initiated a number of sometimes-conflicting and confusing policies aimed, at least nominally, at restoring rangeland productivity. On the basis of a comprehensive literature review, I argue that the extent and magnitude of rangeland degradation on the QTP remains largely unknown because monitoring programs have been subjective and poorly documented. Further, I argue that causes of degradation remain uncertain, often because hypotheses have been articulated too vaguely to test. No phenomena that have been hypothesized as contributing to rangeland degradation on the QTP currently enjoy unequivocal support. Where over-stocking is clearly causing damage, we lack sufficient understanding of current socio-ecological systems to identify ultimate and proximate drivers of pastoralist behavior, and thus policy initiatives aimed at sustainability may well fail. (C) 2009 Elsevier Ltd. All rights reserved. C1 Univ Montana, Coll Forestry, Dept Ecosyst & Conservat Sci, Missoula, MT 59812 USA. RP Harris, RB (通讯作者)，Univ Montana, Coll Forestry, Dept Ecosyst & Conservat Sci, Missoula, MT 59812 USA. EM rharris@montana.com TC 726 Z9 827 PD JAN PY 2010 VL 74 IS 1 BP 1 EP 12 DI 10.1016/j.jaridenv.2009.06.014 UT WOS:000272259700001 DA 2023-03-23 ER PT J AU Liu, L Wu, Y Wu, N Xu, JJ Mao, Y Luo, P Zhang, L AF Liu, Lin Wu, Yan Wu, Ning Xu, Junjun Mao, Yu Luo, Peng Zhang, Lin TI EFFECTS OF FREEZING AND FREEZE-THAW CYCLES ON SOIL MICROBIAL BIOMASS AND NUTRIENT DYNAMICS UNDER DIFFERENT SNOW GRADIENTS IN AN ALPINE MEADOW (TIBETAN PLATEAU) SO POLISH JOURNAL OF ECOLOGY DT Article AB In alpine zones, cold season processes, particularly those associated with snow accumulation and ablation, have a central role in ecosystem functioning. However, we know very little about soil carbon and nitrogen processes under the snowpack in these ecosystems, including the Tibetan Plateau. We conducted an experiment comparing three snow regimes (11 m x 1 m plots) of different snow depths and durations at an altitude of 4,100 m in the Minshan Range on the eastern Tibetan Plateau. The three snow regimes included a shallow and short duration snowpack (SS; depth <10 cm), a moderate snow depth and medium duration snowpack (MS; depth <20 cm), as well as a deep and long duration snowpack (DS; depth > 30 cm). This study explores the effects of different snow conditions on soil temperature, and further describes the sequence and timing of dissolved nutrients and microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) in soils under different snow regimes during the autumn-winter transition (i.e. November 7, 2008 - March 7, 2009). Three successive phases of temperature change were distinguished: I - initial decline - soil temperatures dropped steadily from 4 degrees C to about 0 degrees C at the same rate for all three snow regimes; II - moderate freezing - soil temperatures fluctuated between 0 degrees C and -7 degrees C under all three snow regimes; III - multiple freeze-thaw cycles took place in the SS and MS regimes, but permanent freezing occurred in the DS regime. Under moderate freezing, we found that soil temperature fluctuation was an essential factor for the transformation of soil C and N. Our results indicate that larger temperature fluctuations correlate with a greater increase in dissolved organic nitrogen (DON) content. Dissolved organic carbon (DOC) content increased markedly only under the most drastic temperature fluctuations. In contrast, MBC content increased significantly only when soil temperatures were relatively steady. Under the permanent freezing, only a large number of freeze-thaw cycles caused a significant decline of NO3--N and DOC concentrations. DON content declined markedly under permanent freezing and multiple freeze-thaw cycles. However, MBC content declined significantly only under permanent freezing. Ultimately, multiple freeze-thaw cycles resulted in the export of dissolved nutrients (organic and inorganic nitrogen) from the alpine ecosystem which had previously accumulated in the moderate freezing phase of the soil. C1 [Liu, Lin; Wu, Yan; Wu, Ning; Luo, Peng; Zhang, Lin] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Liu, Lin; Xu, Junjun] Sichuan Agr Univ, Coll Anim Sci & Technol, Yaan 625014, Sichuan, Peoples R China. [Mao, Yu] Univ Sci & Technol Beijing, Appl Sci Sch, Beijing 100083, Peoples R China. RP Wu, N (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, POB 416, Chengdu 610041, Peoples R China. EM wuning@cib.ac.cn TC 10 Z9 23 PY 2010 VL 58 IS 4 BP 717 EP 728 UT WOS:000285679100011 DA 2023-03-23 ER PT J AU Shi, FS Chen, H Wu, Y Wu, N AF Shi, Fusun Chen, Huai Wu, Yan Wu, Ning TI EFFECTS OF LIVESTOCK EXCLUSION ON VEGETATION AND SOIL PROPERTIES UNDER TWO TOPOGRAPHIC HABITATS IN AN ALPINE MEADOW ON THE EASTERN QINGHAI-TIBETAN PLATEAU SO POLISH JOURNAL OF ECOLOGY DT Article AB Long-term overgrazing has resulted in grassland deterioration and even desertification on the eastern Qinghai-Tibetan Plateau. In this paper, we examined the characteristics of vegetation and soil properties in the fivestock-excluded pastures and the adjacent grazed pastures under two topographic habitats (the flat valley and the south-facing slope). Seven-year exclusion of livestock has enhanced aboveground live biomass, root biomass and litter accumulation. Livestock exclusion has also increased soil bulk density and soil water content, soil organic C concentration, total N concentration and its transformation rate, and soil microbial activity. The results showed that livestock exclusion has facilitated vegetation recovery and improved physical, chemical and biological properties of soil. However, livestock exclusion has significantly decreased graminoid biomass accumulation, especially on the flat valley, the biodiversity also significantly decreased there. The results suggested that long-term livestock exclusion was disadvantageous for palatable forage production and biodiversity protection on the flat valley. Compared to the flat valley, the grassland on the south-facing slope was under more severe degradation, and the reversion was in a slower process. Thus, the optimal grassland management in the livestock-excluded pasture on the flat valley should include a low or moderate grazing intensity or adopt an alternate grazing system, but more effective and even longer livestock exclusion practice should be taken on the south-facing slope. C1 [Shi, Fusun; Wu, Yan; Wu, Ning] Chinese Acad Sci, Chengdu Inst Biol, POB 416, Chengdu 610041, Peoples R China. [Shi, Fusun; Chen, Huai] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. [Chen, Huai] Chongqing Univ, Coll Resources & Environm Sci, Chongqing 400030, Peoples R China. RP Wu, N (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, POB 416, Chengdu 610041, Peoples R China. EM wuning@cib.ac.cn TC 25 Z9 32 PY 2010 VL 58 IS 1 BP 125 EP 133 UT WOS:000275881400011 DA 2023-03-23 ER PT C AU Wen, L Dong, SK Zhu, L Li, XY Shi, JJ Wang, YL Ma, YS AF Wen, L. Dong, S. K. Zhu, L. Li, X. Y. Shi, J. J. Wang, Y. L. Ma, Y. S. BE Yang, Z Chen, B TI Change of Soil Organic Carbon Density of Alpine Meadow in the Headwater Areas of Qinghai-Tibetan Plateau, China SO INTERNATIONAL CONFERENCE ON ECOLOGICAL INFORMATICS AND ECOSYSTEM CONSERVATION (ISEIS 2010) SE Procedia Environmental Sciences DT Proceedings Paper CT Biennial International Conference on Ecological Informatics and Ecosystem Conservation (ISEIS) CY AUG 27-29, 2010 CL Beijing, PEOPLES R CHINA AB Qinghai-Tibet Plateau, known as the "World's Ridge", exerts an proud impact carbon pool in sustaining global carbon circulation balance in terms of global climate change. In this study, five sites of alpine grassland at different degradation gradient were surveyed in Guoluo Prefecture of Qinghai Province, China. Soil total organic carbon (TOC) was tested for calculating the density of soil organic carbon, to evaluate the grassland ecosystem function of carbon maintenance. The results showed that the ecosystem function of carbon maintenance for alpine grassland varied along the degradation gradient. The function of both heavily degraded and severely degraded grasslands decreased a lot. However, the function of lightly degraded grassland increased a little compared to the non-degraded grassland. Urgent actions are needed to protect alpine grassland against heavy and severe degradation. (C) 2009 Published by Elsevier Ltd. C1 [Wen, L.; Dong, S. K.; Zhu, L.; Li, X. Y.] Beijing Normal Univ, Environm Sch, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Shi, J. J.; Wang, Y. L.; Ma, Y. S.] Qinghai Acad Anim Sci & Vet Med, Xining 810003, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Environm Sch, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 3 Z9 5 PY 2010 VL 2 BP 619 EP 624 DI 10.1016/j.proenv.2010.10.069 UT WOS:000309520900069 DA 2023-03-23 ER PT C AU Wen, L Dong, SK Zhu, L Li, XY Shi, JJ Wang, YL Ma, YS AF Wen, L. Dong, S. K. Zhu, L. Li, X. Y. Shi, J. J. Wang, Y. L. Ma, Y. S. BE Yang, Z Chen, B TI The construction of Grassland Degradation Index for Alpine Meadow in Qinghai-Tibetan Plateau SO INTERNATIONAL CONFERENCE ON ECOLOGICAL INFORMATICS AND ECOSYSTEM CONSERVATION (ISEIS 2010) SE Procedia Environmental Sciences DT Proceedings Paper CT Biennial International Conference on Ecological Informatics and Ecosystem Conservation (ISEIS) CY AUG 27-29, 2010 CL Beijing, PEOPLES R CHINA AB Diagnosing the degradation degree of grassland ecosystem is the basis for ecological restoration. However, there is no literature documenting how to quantify the grassland degradation degree by using visible indicators. In this study, an integrated degradation index was developed to assess the grassland condition on the basis of applicability and certainty analysis through a cases study from degraded alpine grassland on Qinghai-Tibetan Plateau of China. (C) 2009 Published by Elsevier Ltd. C1 [Wen, L.; Dong, S. K.; Zhu, L.; Li, X. Y.] Beijing Normal Univ, Environm Sch, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Shi, J. J.; Wang, Y. L.; Ma, Y. S.] Qinghai Acad, Anim Sci & Vet Med, Xining 810003, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Environm Sch, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 33 Z9 35 PY 2010 VL 2 BP 1966 EP 1969 DI 10.1016/j.proenv.2010.10.210 UT WOS:000309520900210 DA 2023-03-23 ER PT C AU Zhu, L Dong, SK Wen, L Li, YL Shi, JJ Wang, YL Ma, YS AF Zhu, L. Dong, S. K. Wen, L. Li, Y. L. Shi, J. J. Wang, Y. L. Ma, Y. S. BE Yang, Z Chen, B TI Effect of Cultivated Pasture on Recovering Soil Nutrient of "Black-beach" in the Alpine Region of Headwater Areas of Qinghai-Tibetan Plateau, China SO INTERNATIONAL CONFERENCE ON ECOLOGICAL INFORMATICS AND ECOSYSTEM CONSERVATION (ISEIS 2010) SE Procedia Environmental Sciences DT Proceedings Paper CT Biennial International Conference on Ecological Informatics and Ecosystem Conservation (ISEIS) CY AUG 27-29, 2010 CL Beijing, PEOPLES R CHINA AB Alpine grassland ecosystem of the headwater area of three rivers, Qinghai-Tibet plateau, has been degraded during past decades due to the intensified human activities and climate change. The severely degraded grassland, named "black-beach" has partly been restored with planting the located quality forage and fertilizing in recent years. In this study, we collected soil samples (0-4 depth) from three grasslands at different cultivated ages (cultivation of 4, 7 and 9 years) and one natural grassland at severely degraded level (served as a control) to explore the effect of pasture cultivation on soil nutrients. In addition, the size and the depth of the bare patches in the severely degraded grassland were investigated to estimate cultivated grasslands' capability of fixing the soil substances and recovering the soil nutrients. The results showed that the soil nutrient in the cultivated pasture declined at the early stage of cultivation, increased with cultivated ages, i.e., total N, total C, Ca, and P in soils at 0-4cm depth increased 10-23% after 9 years of cultivation. Pasture cultivations can be regarded as a good strategy to fix the soil surface and recover the soil nutrients of severely degraded grassland on the Qinghai-Tibetan Plateau of China. (C) 2009 Published by Elsevier Ltd. C1 [Zhu, L.; Dong, S. K.; Wen, L.; Li, Y. L.] Beijing Normal Univ, Environm Sch, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. [Shi, J. J.; Wang, Y. L.; Ma, Y. S.] Anim Sci & Vet Med, Qinghai Acad, Xining, Peoples R China. RP Zhu, L (通讯作者)，Beijing Normal Univ, Environm Sch, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 4 Z9 5 PY 2010 VL 2 BP 1355 EP 1360 DI 10.1016/j.proenv.2010.10.146 UT WOS:000309520900146 DA 2023-03-23 ER PT J AU Baumann, F He, JS Schmidt, K Kuhn, P Scholten, T AF Baumann, Frank He, Jin-Sheng Schmidt, Karsten Kuehn, Peter Scholten, Thomas TI Pedogenesis, permafrost, and soil moisture as controlling factors for soil nitrogen and carbon contents across the Tibetan Plateau SO GLOBAL CHANGE BIOLOGY DT Article AB We investigated the main parameters [e.g. mean annual air temperature , mean annual soil temperature, mean annual precipitation, soil moisture (SM), soil chemistry, and physics] influencing soil organic carbon (C-org), soil total nitrogen (N-t) as well as plant available nitrogen (N-min) at 47 sites along a 1200 km transect across the high-altitude and low-latitude permafrost region of the central-eastern Tibetan Plateau. This large-scale survey allows testing the hypothesis that beside commonly used ecological variables, diversity of pedogenesis is another major component for assessing carbon (C) and nitrogen (N) cycling. The aim of the presented research was to evaluate consequences of permafrost degradation for C and N stocks and hence nutrient supply for plants, as the transect covers all types of permafrost including heavily degraded areas and regions without permafrost. Our results show that SM is the dominant parameter explaining 64% of C-org and 60% of N variation. The extent of the effect of SM is determined by permafrost, current aeolian sedimentation occurring mostly on degraded sites, and pedogenesis. Thus, the explanatory power for C and N concentrations is significantly improved by adding CaCO3 content (P=0.012 for C-org; P=0.006 for N-t) and soil texture (P=0.077 for C-org; P=0.015 for N-t) to the model. For soil temperature, no correlations were detected indicating that in high-altitude grassland ecosystems influenced by permafrost, SM overrides soil temperature as the main driving parameter at landscape scale. It was concluded from the current study that degradation of permafrost and corresponding changes in soil hydrology combined with a shift from mature stages of pedogenesis to initial stages, have severe impact on soil C and plant available N. This may alter biodiversity patterns as well as the development and functioning of the ecosystems on the Tibetan Plateau. C1 [Baumann, Frank; Schmidt, Karsten; Kuehn, Peter; Scholten, Thomas] Univ Tubingen, Chair Phys Geog, Inst Geog, D-72070 Tubingen, Germany. [He, Jin-Sheng] Peking Univ, Coll Urban & Environm Sci, Dept Ecol, Beijing 100871, Peoples R China. RP Baumann, F (通讯作者)，Univ Tubingen, Chair Phys Geog, Inst Geog, Rumelinstr 19-23, D-72070 Tubingen, Germany. EM frank.baumann@uni-tuebingen.de TC 141 Z9 161 PD DEC PY 2009 VL 15 IS 12 BP 3001 EP 3017 DI 10.1111/j.1365-2486.2009.01953.x UT WOS:000271710300016 DA 2023-03-23 ER PT J AU Jin, HJ He, RX Cheng, GD Wu, QB Wang, SL Lu, LZ Chang, XL AF Jin, Huijun He, Ruixia Cheng, Guodong Wu, Qingbai Wang, Shaoling Lue, Lanzhi Chang, Xiaoli TI Changes in frozen ground in the Source Area of the Yellow River on the Qinghai-Tibet Plateau, China, and their eco-environmental impacts SO ENVIRONMENTAL RESEARCH LETTERS DT Article AB The Source Area of the Yellow River is located in the mosaic transition zones of seasonally frozen ground, and discontinuous and continuous permafrost on the northeastern Qinghai-Tibet Plateau. Vertically, permafrost is attached or detached from frost action. The latter can be further divided into shallow (depth to the permafrost table <= 8 m), deep (>8 m) and two-layer permafrost. Since the 1980s, air temperatures have been rising at an average rate of 0.02 degrees C yr(-1). Human activities have also increased remarkably, resulting in a regional degradation of permafrost. The lower limit of permafrost has risen by 50-80 m. The average maximum depth of frost penetration has decreased by 0.1-0.2 m. The temperatures of the suprapermafrost water have increased by 0.5-0.7 degrees C. General trends of permafrost degradation include reduction in areal extent from continuous and discontinuous to sporadic and patchy permafrost, thinning of permafrost, and expansion of taliks. Isolated patches of permafrost have either been significantly reduced in areal extent, or changed into seasonally frozen ground. Degradation of permafrost has led to a lowering of ground water levels, shrinking lakes and wetlands, and noticeable change of grassland ecosystems alpine meadows to steppes. The degradation of alpine grasslands will cause further degradation of permafrost and result in the deterioration of ecological environments as manifested by expanding desertification and enhancing soil erosion. C1 [Jin, Huijun; He, Ruixia; Cheng, Guodong; Wu, Qingbai; Wang, Shaoling; Lue, Lanzhi; Chang, Xiaoli] Chinese Acad Sci, State Key Lab Frozen Soils Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Jin, HJ (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soils Engn, Cold & Arid Reg Environm & Engn Res Inst, 326 W Donggang Rd, Lanzhou 730000, Peoples R China. EM hjjin@lzb.ac.cn TC 182 Z9 204 PD OCT-DEC PY 2009 VL 4 IS 4 AR 045206 DI 10.1088/1748-9326/4/4/045206 UT WOS:000272900500063 DA 2023-03-23 ER PT J AU Li, WJ Li, JH Knops, JMH Wang, G Jia, JJ Qin, YY AF Li, Wen-Jin Li, Jin-Hua Knops, Johannes M. H. Wang, Gang Jia, Ju-Jie Qin, Yan-Yan TI Plant Communities, Soil Carbon, and Soil Nitrogen Properties in a Successional Gradient of Sub-Alpine Meadows on the Eastern Tibetan Plateau of China SO ENVIRONMENTAL MANAGEMENT DT Article AB To assess the recovery trajectory and self-maintenance of restored ecosystems, a successional gradient (1, 3, 5, 15, and 30 years after abandonment) was established in a sub-alpine meadow of the eastern Tibetan Plateau in China. Plant communities and soil carbon and nitrogen properties were investigated and analyzed. Regression analyses were used to assess the models (linear or quadratic) relating measures of species richness, soil carbon and nitrogen properties to fallow time. We found that species richness (S) increased over the first 20 years but decreased thereafter, and aboveground biomass showed a linear increase along the fallow time gradient. The richness of different functional groups (forb, grass and legume) changed little along the fallow time gradient, but their corresponding above ground biomass showed the U-shaped, humped or linear pattern. Soil microbial carbon (MBC) and nitrogen (MBN) in the upper 20 cm showed a U-shaped pattern along the fallow time gradient. However, soil organic carbon (C-org) and total nitrogen (TN) in the soil at depth greater than 20 cm showed significant patterns of linear decline along the fallow time gradient. The threshold models of species richness reflected best the recovery over the 15 year fallow period. These results indicated that fallow time had a greater influence on development of the plant community than soil processes in abandoned fields in sub-alpine meadow ecosystem. These results also suggested that although the succession process did not significantly increase soil C, an increase in microbial biomass at the latter stage of succession could promote the decomposability of plant litter. Therefore, abandoned fields in sub-alpine meadow ecosystem may have a high resilience and strong rehabilitating capability under natural recovery condition. C1 [Li, Wen-Jin; Li, Jin-Hua; Wang, Gang; Jia, Ju-Jie; Qin, Yan-Yan] Lanzhou Univ, Key Lab Arid & Grassland Agroecol, Lanzhou 730000, Peoples R China. [Knops, Johannes M. H.] Univ Nebraska, Sch Biol Sci, Lincoln, NE 68588 USA. RP Li, JH (通讯作者)，Lanzhou Univ, Key Lab Arid & Grassland Agroecol, Lanzhou 730000, Peoples R China. EM wenjinli@yahoo.com.cn; lijinhuap@sohu.com TC 23 Z9 25 PD OCT PY 2009 VL 44 IS 4 BP 755 EP 765 DI 10.1007/s00267-009-9361-1 UT WOS:000270448900012 DA 2023-03-23 ER PT J AU Li, XG Zhang, ML Li, ZT Shi, XM Ma, QF Long, RJ AF Li, Xiao Gang Zhang, Mei Lan Li, Zhuo Ting Shi, Xiao Ming Ma, Qifu Long, Rui Jun TI Dynamics of soil properties and organic carbon pool in topsoil of zokor-made mounds at an alpine site of the Qinghai-Tibetan Plateau SO BIOLOGY AND FERTILITY OF SOILS DT Article AB The population of burrowing plateau zokors (Myospalax baileyi) was markedly increased in the Qinghai-Tibetan Plateau. The objective of this study was to investigate the effects of zokor foraging and mound-making disturbance on topsoil properties and organic C pools at an alpine site of the Qinghai-Tibetan Plateau. Surface (0-15 cm) soil samples were collected from mounds with different ages (3 months and 3, 6, and 15 years) and from undisturbed grassland. Above- and below-ground plant biomasses were depleted by zokors in newly created mounds (3 months). Plant cover and root biomass gradually recovered thereafter, but were still lower in the 15-year-old mounds than in the undisturbed soils. Organic C contents of coarse (> 2 mm), soil (< 2 mm), particulate (2-0.05 mm) fractions, and microbial biomass, organic C mineralization, beta-glucosidase activity, urease activity, alkaline phosphatase activity, acid phosphatase activity, and soil aggregation were significantly lower in the 3, 6, and 15-year-old mound soils than in the undisturbed soils or newly created mound soils. Fifteen years after mound creation, the soil had only 12% of root biomass, 35% of coarse organic C, 83% of particulate organic C, 58% of microbial biomass C, 57% of 30-day respired C, and 45% of water-stable aggregate mean weight diameter, compared to values of the undisturbed soils. Our results suggested that foraging and mound-making by zokors have negative impacts on properties and organic matter content of the topsoil. C1 [Li, Xiao Gang; Zhang, Mei Lan; Li, Zhuo Ting; Shi, Xiao Ming; Ma, Qifu; Long, Rui Jun] Lanzhou Univ, Sch Life Sci, MOE Key Lab Arid & Grassland Ecol, Lanzhou 730000, Peoples R China. [Ma, Qifu] Univ Western Australia, Sch Plant Biol, Crawley, WA 6009, Australia. RP Li, XG (通讯作者)，Lanzhou Univ, Sch Life Sci, MOE Key Lab Arid & Grassland Ecol, Tianshui S Rd 222, Lanzhou 730000, Peoples R China. EM lixiaogang@lzu.edu.cn TC 26 Z9 32 PD SEP PY 2009 VL 45 IS 8 BP 865 EP 872 DI 10.1007/s00374-009-0398-3 UT WOS:000269418000009 DA 2023-03-23 ER PT J AU Li, YS Wang, GX Ding, YJ Zhao, L Wang, YB AF Li, Y. S. Wang, G. X. Ding, Y. J. Zhao, L. Wang, Y. B. TI Application of the Cs-137 tracer technique to study soil erosion of alpine meadows in the headwater region of the Yellow River SO ENVIRONMENTAL GEOLOGY DT Article AB The Cs-137 tracer technique was used to study soil erosion of alpine meadow grassland in two small river basins in the headwater region of the Yellow River. The results show that the levels of Cs-137 in soil samples from this alpine meadow vegetation zone exhibit an exponential distribution, generally within a depth of approximately 20 cm. Due to strong winds, freeze-thaw cycles and water, soil erosion was found to be stronger on the upper slope than on the lower slope, and except for the slope crest, the intensity of soil erosion at other sites was as follows: upslope < midslope < downslope. There was a significant negative correlation between the intensity of soil erosion and the extent of alpine meadow vegetation cover (P < 0.01). The mean soil erosion modulus exhibited a linear reduction trend with an increase in vegetation cover, and the correlation coefficient R (2) was a parts per thousand yen 0.997. The higher the degradation degree of the alpine meadow grassland, the greater is the soil erosion. The mean erosion modulus in the severely degraded meadow zone was 2.23 times greater than the one in the slightly degraded zone, and the maximum erosion modulus reached 2.96 x 10(6) kg/km(2)/a. C1 [Li, Y. S.; Wang, G. X.; Ding, Y. J.; Zhao, L.] Chinese Acad Sci, State Key Lab Cryospher Sci, Cold & Arid Reg Environm & Engn Res Inst, Cryosphere Res Stn Qinghai Xizang Plateau Sci, Lanzhou 730000, Peoples R China. [Wang, G. X.] Chinese Acad Sci, Inst Mt Hazard & Environm, Chengdu 610041, Peoples R China. [Wang, G. X.] Minist Water Conservancy & Power, Chengdu 610041, Peoples R China. [Wang, Y. B.] Lanzhou Univ, Coll Resources & Environm, Lanzhou 730000, Peoples R China. RP Li, YS (通讯作者)，Chinese Acad Sci, State Key Lab Cryospher Sci, Cold & Arid Reg Environm & Engn Res Inst, Cryosphere Res Stn Qinghai Xizang Plateau Sci, Lanzhou 730000, Peoples R China. EM yshli@lzb.ac.cn TC 1 Z9 2 PD SEP PY 2009 VL 58 IS 5 BP 1021 EP 1028 DI 10.1007/s00254-008-1581-9 UT WOS:000269014000011 DA 2023-03-23 ER PT J AU Wang, SP Yang, XX Lin, XW Hu, YG Luo, CY Xu, GP Zhang, ZH Su, AL Chang, XF Chao, ZG Duan, JC AF Wang, Shiping Yang, Xiaoxia Lin, Xingwu Hu, Yigang Luo, Caiyun Xu, Guangping Zhang, Zhenhua Su, Ailing Chang, Xiaofen Chao, Zengguo Duan, Jichuang TI Methane emission by plant communities in an alpine meadow on the Qinghai-Tibetan Plateau: a new experimental study of alpine meadows and oat pasture SO BIOLOGY LETTERS DT Article AB Recently, plant-derived methane (CH4) emission has been questioned because limited evidence of the chemical mechanism has been identified to account for the process. We conducted an experiment with four treatments (i.e. winter-grazed, natural alpine meadow; naturally restored alpine meadow eight years after cultivation; oat pasture and bare soil without roots) during the growing seasons of 2007 and 2008 to examine the question of CH4 emission by plant communities in the alpine meadow. Each treatment consumed CH4 in closed, opaque chambers in the field, but two types of alpine meadow vegetation reduced CH4 consumption compared with bare soil, whereas oat pasture increased consumption. This result could imply that meadow vegetation produces CH4. However, measurements of soil temperature and water content showed significant differences between vegetated and bare soil and appeared to explain differences in CH4 production between treatments. Our study strongly suggests that the apparent CH4 production by vegetation, when compared with bare soil in some previous studies, might represent differences in soil temperature and water-filled pore space and not the true vegetation sources of CH4. C1 [Wang, Shiping; Yang, Xiaoxia; Hu, Yigang; Luo, Caiyun; Xu, Guangping; Zhang, Zhenhua; Su, Ailing; Chang, Xiaofen; Chao, Zengguo; Duan, Jichuang] Chinese Acad Sci, NW Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Yang, Xiaoxia; Hu, Yigang; Luo, Caiyun; Xu, Guangping; Zhang, Zhenhua; Su, Ailing; Chang, Xiaofen; Chao, Zengguo; Duan, Jichuang] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. [Lin, Xingwu] Chinese Acad Sci, Inst Soil Sci Nanjing, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, NW Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. EM wangship2008@yahoo.cn TC 25 Z9 41 PD AUG 23 PY 2009 VL 5 IS 4 BP 535 EP 538 DI 10.1098/rsbl.2009.0123 UT WOS:000267881700028 DA 2023-03-23 ER PT J AU Xue, X Guo, J Han, BSA Sun, QW Liu, LC AF Xue, Xian Guo, Jian Han, Bangshuai Sun, Qingwei Liu, Lichao TI The effect of climate warming and permafrost thaw on desertification in the Qinghai-Tibetan Plateau SO GEOMORPHOLOGY DT Article AB Four sets of remote sensing images from 1987,1994, 2000, and 2006, 50 years of meteorological and soil moisture data corresponding to different desertified lands were combined with populations and livestock data to analyze the process and cause of desertification in a portion of the Qinghai-Tibetan Plateau (QTP). It showed that surface soil temperature in the region has increased at an average rate of 0.6 degrees C per decade between 1980 and 2005, the thawing days on the surface have increased by 60 days from 1983 to 2001, and the depth of the seasonal thawing layer has increased by 54 cm, 102 cm and 77 cm in April, May and June, respectively, from 1983 to 2003. As a result, the upper soil layer has become drier due to the thickening active layer and soil water infiltration. These changes, in turn, have inhibited the growth of alpine meadow vegetation that has shallow root systems. It is concluded that climate warming and permafrost thawing have caused desertification in grazing regions of the Qinghai-Tibetan Plateau (QTP). (C) 2009 Elsevier B.V. All rights reserved. C1 [Xue, Xian; Guo, Jian; Han, Bangshuai; Sun, Qingwei; Liu, Lichao] Chinese Acad Sci, Cold & Arid Regs Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Xue, X (通讯作者)，Chinese Acad Sci, Cold & Arid Regs Environm & Engn Res Inst, W Donggang Rd 320, Lanzhou 730000, Peoples R China. EM xianxue@lzb.ac.cn TC 136 Z9 162 PD JUL 15 PY 2009 VL 108 IS 3-4 BP 182 EP 190 DI 10.1016/j.geomorph.2009.01.004 UT WOS:000267180500004 DA 2023-03-23 ER PT J AU Gao, QZ Li, Y Wan, YF Jiangcun, WZ Qin, XB Wang, BS AF Gao, Qing-zhu Li, Yue Wan, Yun-fan Jiangcun, Wang-zha Qin, Xiao-bo Wang, Bao-shan TI Significant Achievements in Protection and Restoration of Alpine Grassland Ecosystem in Northern Tibet, China SO RESTORATION ECOLOGY DT Article AB Alpine grassland is a fragile ecosystem, and a large area of this grassland type has been severely degraded in Northern Tibet, to the extent that it has become the primary ecological problem in the region. Various levels of government, including the national central government, the Tibetan Autonomous Region government, and the Nagqu Prefecture government have worked together to achieve alpine grassland ecosystem protection and prevent grassland degradation. These efforts have resulted in significant ecological, social, and economic benefits in Northern Tibet. C1 [Gao, Qing-zhu; Li, Yue; Wan, Yun-fan; Qin, Xiao-bo] Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. [Gao, Qing-zhu; Li, Yue; Wan, Yun-fan; Qin, Xiao-bo] Minist Agr, Key Lab Agroenvironm & Climate Change, Beijing 100081, Peoples R China. [Jiangcun, Wang-zha; Wang, Bao-shan] Nagqu Grassland Stn, Nagqu 852100, Peoples R China. RP Li, Y (通讯作者)，Chinese Acad Agr Sci, Inst Environm & Sustainable Dev Agr, Beijing 100081, Peoples R China. EM yueli@ami.ac.cn TC 39 Z9 47 PD MAY PY 2009 VL 17 IS 3 BP 320 EP 323 DI 10.1111/j.1526-100X.2009.00527.x UT WOS:000265713100002 DA 2023-03-23 ER PT J AU Lu, X Ke, DH Zeng, XH Gong, GH Ci, R AF Lu, Xin Ke, Dianhua Zeng, Xianhai Gong, Guohong Ci, Ren TI Status, Ecology, and Conservation of the Himalayan Griffon Gyps himalayensis (Aves, Accipitridae) in the Tibetan Plateau SO AMBIO DT Article AB The dramatic population crashes of 3 species of Gyps vulture have raised concerns about the status of their lesser-known congeners. Among these is the Himalayan griffon, G. himalayensis, an iconic vulture of the Tibetan plateau. The continued existence of this scavenger has not only ecological but also cultural implications because of their unique role in the centuries-old sky burial tradition that is followed by nearly 5 million Tibetan people. A lack of baseline information of the Himalayan griffon limits our ability to take conservation measures. The presented data, which were collected during 1996 and 2004 to 2007, indicate that this species is still widespread throughout the plateau and has not experienced a major population decline, likely as a result of protection by Tibetan Buddhism and limited disturbances from human activities largely due to the remoteness of the plateau. Both site and road counts showed that open meadow habitats had the highest griffon abundance, followed by alpine shrub and forest habitats. Estimates based on road transect counts showed that 229 339 Himalayan griffons (+/- 40 447) occupy the 2.5 million km(2) Tibetan plateau. In contrast, the maximum carrying capacity of the plateau, on the basis of the total biomass of potential food resources, is 507 996 griffons, with meadow habitats accounting for about 76% of the total population. Griffons depend largely on livestock carcasses for food and forage in groups averaging 5.5 (range 1-100) individuals. Domestic yaks provide about 64% of the griffons' diet, while wild ungulates and human corpses provide 1% and 2%, respectively. Compared with its lowland congeners, this, the only high-elevation Gyps species, had both low population density and small group size, a likely response to the harsh environmental conditions. Although griffon abundance appears relatively stable in their fairly pristine environment, precautionary measures, including investigation of threats, monitoring of population dynamics, and establishment of modern conservation consciousness among Tibetan Buddhists, should be carried out to ensure that this abundance continues. C1 [Lu, Xin; Ke, Dianhua; Zeng, Xianhai; Gong, Guohong] Wuhan Univ, Coll Life Sci, Dept Zool, Wuhan 430072, Peoples R China. [Ci, Ren] Tibet Univ, Dept Biol Sci, Lhasa 850000, Peoples R China. RP Lu, X (通讯作者)，Wuhan Univ, Coll Life Sci, Dept Zool, Wuhan 430072, Peoples R China. EM luxinwh@163.com; ssk002@tom.com; whu2003ecology@163.com; ghgong@163.com; tseringdorge@yahoo.com.cn TC 11 Z9 19 PD MAY PY 2009 VL 38 IS 3 BP 166 EP 173 DI 10.1579/0044-7447-38.3.166 UT WOS:000266276300007 DA 2023-03-23 ER PT J AU Lin, XW Wang, SP Ma, XZ Xu, GP Luo, CY Li, YN Jiang, GM Xie, ZB AF Lin, Xingwu Wang, Shiping Ma, Xiuzhi Xu, Guangping Luo, Caiyun Li, Yingnian Jiang, Gaoming Xie, Zubin TI Fluxes of CO2, CH4, and N2O in an alpine meadow affected by yak excreta on the Qinghai-Tibetan plateau during summer grazing periods SO SOIL BIOLOGY & BIOCHEMISTRY DT Article AB To assess the impacts of yak excreta patches on greenhouse gas (GHG) fluxes in the alpine meadow of the Qinghai-Tibetan plateau. methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) fluxes were measured for the first time from experimental excreta patches placed on the meadow during the summer grazing seasons in 2005 and 2006. Dung patches were CH4 sources (average 586 mu g m(-2) h(-1) in 2005 and 199 mu g m(-2) h(-1) in 2006) during the investigation period of two years, while urine patches (average -31 mu g m(-2) h(-1) in 2005 and -33 mu g m(-2) h(-1) in 2006) and control plots (average -28 mu g m(-2) h(-1) in 2005 and -30 mu g m(-2) h(-1) in 2006) consumed CH4. The cumulative CO2 emission for dung patches was about 36-50% higher than control plots during the experimental period in 2005 and 2006. The cumulative N2O emissions for both urine and dung patches were 2.1-3.7 and 1.8-3.5 times greater than control plots in 2005 and 2006, respectively. Soil water-filled pore space (WFPS) explained 35% and 36% of CH4 flux variation for urine patches and control plots, respectively. Soil temperature explained 40-75% of temporal variation of CO2 emissions for all treatments. Temporal N2O flux variation in urine patches (34%), dung patches (48%), and control (56%) plots was mainly driven by the simultaneous effect of soil temperature and WFPS. Although yak excreta patches significantly affected GHG fluxes, their contributions to the whole grazing alpine meadow in terms of CO2 equivalents are limited under the moderate grazing intensity (1.45 yak ha(-1)). However, the contributions of excreta patches to N2O emissions are not negligible when estimating N2O emissions in the grazing meadow. In this study, the N2O emission factor of yak excreta patches varied with year (about 0.9-1.0%, and 0.1-0.2% in 2005 and 2006, respectively), which was lower than IPCC default value of 2%. (C) 2009 Elsevier Ltd. All rights reserved. C1 [Wang, Shiping; Xu, Guangping; Luo, Caiyun; Li, Yingnian] Chinese Acad Sci, NW Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. [Lin, Xingwu; Jiang, Gaoming] Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China. [Lin, Xingwu] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. [Lin, Xingwu; Xie, Zubin] Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Peoples R China. [Ma, Xiuzhi] Inner Mongolia Agr Univ, Coll Forestry, Hohhot 010018, Peoples R China. RP Wang, SP (通讯作者)，Chinese Acad Sci, NW Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810008, Peoples R China. EM wangship2008@yahoo.cn TC 117 Z9 141 PD APR PY 2009 VL 41 IS 4 BP 718 EP 725 DI 10.1016/j.soilbio.2009.01.007 UT WOS:000265325300008 DA 2023-03-23 ER PT J AU Wang, GX Li, SN Hu, HC Li, YS AF Wang Genxu Li Shengnan Hu Hongchang Li Yuanshou TI Water regime shifts in the active soil layer of the Qinghai-Tibet Plateau permafrost region, under different levels of vegetation SO GEODERMA DT Article AB Soil moisture and water cycling in a permafrost active layer are affected in a synergistic manner by both the sequence of soil temperature and changes in vegetative cover. Between 2004 and 2007, the dynamics of soil water content and water movement in the active layer of alpine meadow soils were monitored at sites located in the permafrost region of the Qinghai-Tibetan Plateau, China for four years to examine the synergistic effects of freeze-thaw cycles and levels of vegetation cover. The analysis of variations in monthly and seasonal soil moisture, soil-desiccation index, and soil available indicated that soil moisture exhibited a relatively stable and consistent pattern over the growing season (July-September), independent from the vegetation cover. Greater soil moisture was present in the upper root zone and at the bottom of the soil profile, whereas lower moisture levels occurred in the middle portion of the profile. Irrespective of soil depth, the lower the vegetation cover, the quicker the increase in soil liquid water during the thaw initiation period (May and June), and the quicker its decrease during the freeze initiation period (October and November). In addition, the greater the vegetation cover, the greater the available water content of the upper root zone and the less the water content of the soil layer at 0.60-0.70 m depth below the root zone. Both the soil hydraulic parameters and the spatiotemporal distribution of the water content were subject to the synergistic action of the freeze-thaw cycle and the extent of vegetation cover. The variances in active soil heat transmission and heat-water coupling relationship under the different vegetation covers were considered the main driving factors in the distribution and dynamics of the active soil water regime. The permafrost supports the development of alpine frost meadow ecosystems, and well-ordered, high-cover alpine meadow vegetation favors the protection of permafrost from degradation. (C) 2009 Published by Elsevier B.V. C1 [Wang Genxu; Li Shengnan] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Hu Hongchang] Lanzhou Univ, Coll Resources & Environm, Lanzhou 730000, Peoples R China. [Li Yuanshou] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM gxwang@ns.lzb.ac.cn TC 39 Z9 49 PD MAR 15 PY 2009 VL 149 IS 3-4 BP 280 EP 289 DI 10.1016/j.geoderma.2008.12.008 UT WOS:000264360100013 DA 2023-03-23 ER PT J AU Chen, H Wu, N Gao, YH Wang, YF Luo, P Tian, JQ AF Chen, Huai Wu, Ning Gao, Yongheng Wang, Yanfen Luo, Peng Tian, Jianqing TI Spatial variations on methane emissions from Zoige alpine wetlands of Southwest China SO SCIENCE OF THE TOTAL ENVIRONMENT DT Article AB This study was aimed to understand the spatial variation of CH4 emissions from alpine wetlands in Southwest China on a field-scale in two phenological seasons, namely the peak growing season and the spring thaw. Methane emission rates were measured at 30 plots, which included three kinds of environmental types: dry hummock, Carex muliensis and Eleocharis valleculosa sites. There were highly spatial variations of methane emissions among and within different environmental types in both phenological seasons. Mean methane emission rates ranged from 1.1 to 37.0 mg CH4 m(-2) h(-1) in the peak growing season and from 0.004 to 0.691 mg CH4 m(-2) h(-1) in the spring thaw. In the peak growing season, coefficients of variation (CV) averaged 38% among environmental types and 64% within environmental types; while in the spring thaw, CV were on the average 61% among environmental types and 96% within environmental types. The key influencing factors were the standing water table and the plant community height in the peak growing season, while in the spring thaw, no significant correlations between factors and methane emissions were found. (C) 2008 Elsevier B.V. All rights reserved C1 [Chen, Huai; Wu, Ning; Luo, Peng] Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China. [Chen, Huai] Chongqing Univ, Coll Resources & Environm Sci, Chongqing 400044, Peoples R China. [Chen, Huai] Minist Educ, Key Lab Exploitat SW Resources & Environm Disaste, Chongqing 400044, Peoples R China. [Gao, Yongheng] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Wang, Yanfen] Chinese Acad Sci, Grad Sch, Coll Resources & Environm, Beijing 100049, Peoples R China. [Tian, Jianqing] Chinese Acad Sci, Grad Sch, Dept Biol, Beijing 100049, Peoples R China. RP Wu, N (通讯作者)，Chinese Acad Sci, Chengdu Inst Biol, Chengdu 610041, Peoples R China. EM chenhuai8l@gmail.com; wuning@cib.ac.cn TC 53 Z9 65 PD JAN 15 PY 2009 VL 407 IS 3 BP 1097 EP 1104 DI 10.1016/j.scitotenv.2008.10.038 UT WOS:000262660800012 DA 2023-03-23 ER PT J AU Li, SX Wang, QJ Jing, ZC Wang, WY AF Li, Shixiong Wang, Qiji Jing, Zengchun Wang, Wenying TI EFFECTS OF PROTECTIVE ENCLOSURE ON VEGETATION DIVERSITY, AND PRODUCTIVITY OF DEGRADED ALPINE KOBRESIA MEADOW (QINGHAI-TIBETAN PLATEAU) SO POLISH JOURNAL OF ECOLOGY DT Article AB Grassland degradation due to anthropogenic and natural factors and their interactions is one of the worldwide ecological and economic problems because it reduces grassland productivity and diversity and leads to desertification. The objective of this study was to assess the influence of protective enclosure on vegetation composition and diversity and plant biomass of an alpine degraded meadow. The experiment was conducted at center of Qinghai-Tibetan Plateau with two degraded (caused by overgrazing) alpine meadows: the lightly and severely degraded ones (LD and SD) and their enclosed areas with iron net (LDE and SDE, respectively). The areas 200 m x 150 m for each of four degraded alpine meadow treatments at average altitude 3,960 m a.s.l. were set for research. The lightly degraded plots were dominated by Scirpus distigmaticus (Kukenth.) Tang et Wang, Elymus nutans Griseb. and Oxytropis ochrocephala Bunge. The dominating plants in severely degraded plots were: Artemisia sieversiana Ehrhart ex Willd, Ajania tenuifolia (Jacq.) Tzvel, Lonicera minuta Batal. The results showed: (1) the vegetation cover of two degraded plots (LD and SD) has increased after taking the enclosure measures and the forbs dominated both plots. (2) Species richness has also increased in two enclosed degraded plots, respectively. There no significant differences in evenness and diversity between LD and LDE, and SD and SDE, respectively. (3) Enclosure may promote aboveground biomass, particularly grass and forb biomass in LD, and forb biomass in SD plots. C1 [Li, Shixiong; Wang, Qiji; Jing, Zengchun] Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Peoples R China. [Li, Shixiong] Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China. [Wang, Wenying] Qinghai Normal Univ, Coll Life Sci, Xining 810008, Peoples R China. RP Wang, QJ (通讯作者)，Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Peoples R China. EM wqj@nwipb.ac.cn TC 5 Z9 9 PY 2009 VL 57 IS 3 BP 495 EP 502 UT WOS:000270012200007 DA 2023-03-23 ER PT J AU Du, YG Cui, YG Xu, XL Liang, DY Long, RJ Cao, GM AF Du, Yangong Cui, Yingguang Xu, Xingliang Liang, Dongying Long, Ruijun Cao, Guangmin TI Nitrous oxide emissions from two alpine meadows in the Qinghai-Tibetan Plateau SO PLANT AND SOIL DT Article AB Nitrous oxide (N2O) emission was measured in a Kobresia humilis meadow and a Potentilla fruticosa meadow in the Qinghai-Tibet Plateau from June 2003 to July 2006. Five treatments were setup in the two alpine meadows. Two bare soil treatments were setup in the K. humilis meadow (BSK) and in the P. fruticosa meadow (BSP) by removing the above- and belowground plant biomass. Three plant community treatments were setup with one in the K. humilis meadow (herbaceous community in the K. humilis meadow-HCK) and two in the P. fruticosa meadow (herbaceous community in the P. fruticosa meadow-HCP, and shrub community in the P. fruticosa meadow-SCP). Nitrous oxide emission from BSP was estimated to be 38.1 +/- 3.6 mu g m(-2) h(-1), significantly higher than from BSK (30.2 +/- 2.8 mu g m(-2) h(-1)) during the whole experiment period. Rates from the two herbaceous blocks (HCK and HCP) were close to 39.5 mu g m(-2) stop h(-1) during the whole experimental period whereas shrub community (SCP) showed significant high emission rates of N2O. Annual rate of N2O emission was estimated to be 356.7 +/- 8.3 and 295.0 +/- 11.6 mg m(-2) year(-1) from the alpine P. fruticosa meadow and from the alpine K. humilis meadow, respectively. These results suggest that alpine meadows in the Qinghai-Tibetan Plateau are an important source of N2O, contributing an average of 0.3 Tg N2O year(-1). We concluded that N2O emission will decrease, due to a predicted vegetation shift from shrubs to grasses imposed by overgrazing. C1 [Du, Yangong; Liang, Dongying; Cao, Guangmin] Chinese Acad Sci, NW Inst Plateau Biol, Xining 810001, Qinghai, Peoples R China. [Du, Yangong] Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China. [Cui, Yingguang] Second High Sch Binzhou, Binzhou 256621, Shandong, Peoples R China. [Xu, Xingliang] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modelling, Beijing 100101, Peoples R China. [Long, Ruijun] Lanzhou Univ, Sch Pastoral Agr Sci & Technol, Lanzhou 730020, Gansu, Peoples R China. RP Cao, GM (通讯作者)，Chinese Acad Sci, NW Inst Plateau Biol, 59 Xiguan Dajie, Xining 810001, Qinghai, Peoples R China. EM caogm@nwipb.ac.cn TC 41 Z9 56 PD OCT PY 2008 VL 311 IS 1-2 BP 245 EP 254 DI 10.1007/s11104-008-9727-9 UT WOS:000259042800021 DA 2023-03-23 ER PT J AU Nakano, T Nemoto, M Shinoda, M AF Nakano, Tomoko Nemoto, Manabu Shinoda, Masato TI Environmental controls on photosynthetic production and ecosystem respiration in semi-arid grasslands of Mongolia SO AGRICULTURAL AND FOREST METEOROLOGY DT Article AB The Mongolian steppe zone comprises a major part of East Asian grasslands. The objective of this study was to separately evaluate the quantitative dependencies of gross primary production (GPP) and ecosystem respiration (R-eco) on the environmental variables of temperature, moisture, radiation, and plant biomass in a semi-arid grassland ecosystem. We determined GPP and Reco using transparent and opaque closed chambers in a grassland dominated by Poaceae species in central Mongolia during five periods: July 2004, May 2005, July 2005, September 2005, and June 2006. Values of GPP were linearly related to live aboveground biomass (AGB) enclosed by the chamber. The amount of GPP per unit ground area differed among the study periods, whereas GPP normalized by the amount of AGB did not differ significantly among the periods, suggesting that plant production per unit green biomass did not depend on the phenological stage. GPP/AGB fit well a rectangular hyperbolic light-response curve for all the study periods. When the air and soil were dry, considerable reduction in GPP was observed. The GPP/AGB ratio was also expressed as individual functions of air temperature, vapor pressure deficit, and volumetric soil water content. Reco was exponentially related to the soil temperature and the relationship was modified by soil moisture. The amount of R,c and its temperature sensitivity (Q(10)) declined with decreasing soil moisture. Sharp increases of Re, after rainfall events were observed. The values of Re,, even including the rain-induced pulses, were expressed well as a bivariate function of soil temperature and soil moisture near the soil surface. (C) 2008 Elsevier B.V. All rights reserved. C1 [Nakano, Tomoko] Tokyo Metropolitan Univ, Dept Geog, Tokyo 1920397, Japan. [Nemoto, Manabu] Natl Agr Res Ctr Hokkaido Reg, Toyohira Ku, Sapporo, Hokkaido 0628555, Japan. [Shinoda, Masato] Tottori Univ, Arid Land Res Ctr, Tottori 6800001, Japan. RP Nakano, T (通讯作者)，Tokyo Metropolitan Univ, Dept Geog, 1-1 Minami Osawa, Tokyo 1920397, Japan. EM nakanot@comp.metro-u.ac.jp TC 67 Z9 79 PD SEP 3 PY 2008 VL 148 IS 10 BP 1456 EP 1466 DI 10.1016/j.agrformet.2008.04.011 UT WOS:000259683600007 DA 2023-03-23 ER PT J AU Wang, H Zhou, XL Wan, CG Fu, H Zhang, F Ren, JZ AF Wang, Hui Zhou, Xiaolei Wan, Changgui Fu, Hua Zhang, Feng Ren, Jizhou TI Eco-environmental degradation in the northeastern margin of the Qinghai-Tibetan Plateau and comprehensive ecological protection planning SO ENVIRONMENTAL GEOLOGY DT Article AB The regional hydrology and ecosystems of the northeastern margin of the Qinghai-Tibetan Plateau have changed over the past 40 years driven by intense human activity and regional climate changes. Annual mean air temperature has increased in the region. Streamflow from the northeastern margin of the Qinghai-Tibetan Plateau has decreased significantly. Overall, a number of Alpine step meadows and Alpine frigid meadows have seriously degraded. Degeneration of vegetation and grassland led to desertification and frequently induced dust storms. With the continuous increase in cultivated land area, grassland area in the region has dropped significantly since the 1960s. At present, degraded grassland occupies about 83% of total usable grassland area. As the number of livestock increased, range condition deteriorated and the carrying capacity was reduced. The forest area in the northeastern margin of the Qinghai-Tibetan Plateau has decreased by 20%, and the local ecosystem has become very fragile. Given the relatively stable weather conditions, the northeastern margin of the Qinghai-Tibetan Plateau can be characterized by its three major ecosystems: grassland ecosystem, forest ecosystem and wetland ecosystem, which are crucial in maintaining the ecological stability. Changes in these ecosystems could influence sustainable development in the region. To avoid further deterioration of the environment and ecosystems, it is important to establish and implement ecosystem protection planning. Some effective measures are essential in this respect, including technical and political considerations. C1 [Wang, Hui; Zhou, Xiaolei; Fu, Hua; Zhang, Feng; Ren, Jizhou] Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Lanzhou 730000, Peoples R China. [Zhou, Xiaolei; Wan, Changgui] Forest Inventory & Planning Inst Gansu Prov, Lanzhou 730020, Peoples R China. [Wan, Changgui] Texas Tech Univ, Dept Nat Resources Management, Lubbock, TX 79409 USA. [Wang, Hui] Gansu Agr Univ, Coll Forestry, Lanzhou 730070, Peoples R China. RP Zhou, XL (通讯作者)，Duanjiatan Rd 1234, Lanzhou 730020, Gansu, Peoples R China. EM zhouxiaolei1555@sina.com TC 42 Z9 49 PD SEP PY 2008 VL 55 IS 5 BP 1135 EP 1147 DI 10.1007/s00254-007-1061-7 UT WOS:000258529400019 DA 2023-03-23 ER PT J AU Arthur, AD Pech, RP Davey, C Jiebu Zhang, YM Lin, H AF Arthur, Anthony D. Pech, Roger P. Davey, Chris Jiebu Zhang Yanming Lin Hui TI Livestock grazing, plateau pikas and the conservation of avian biodiversity on the Tibetan plateau SO BIOLOGICAL CONSERVATION DT Article AB On the Qinghai-Tibet plateau increased livestock numbers have resulted in degradation of the grasslands with potential impacts on native biodiversity. Concurrently, perceived increases in populations of native small mammals such as plateau pikas (Ochotona curzoniae) have led to poisoning programs, with uncertain impacts on species such as ground-nesting birds. We explored the relationships between the local seasonal abundance of small birds and (1) the density of pika burrows; (2) livestock grazing practices; and (3) local poisoning of pikas. Around Naqu prefecture, central Tibet, we used a nested experimental design to collect data from areas rested from grazing over summer, nearby areas with year-round grazing and areas subjected to pika poisoning. Additional data were collected from a site where grazing had not occurred for at least 4 years prior to the study. Poisoning pikas in spring had no detectable effect on the local abundance of birds the following autumn. However, two ground-nesting species, white-rumped and rufous-necked snowfinches, showed positive associations with the density of pika burrows, indicating that long-term 'pika poisoning could reduce the density of these species by reducing the density of pika burrows. Rufous-necked snowfinches and non ground-nesting species including horned larks and common hoopoes showed positive responses to reduced grazing pressure from livestock, particularly in the long-rested site, indicating current grazing levels could be having a negative impact on these species. Conservation of small passerine biodiversity in this system will require changed management practices for livestock and pikas that consider the complex three-way interaction between livestock grazing, pikas and small birds. (C) 2008 Elsevier Ltd. All rights reserved. C1 [Arthur, Anthony D.; Pech, Roger P.; Davey, Chris] CSIRO Sustainable Ecosyst, Canberra, ACT 2601, Australia. [Jiebu] Tibet Acad Agr & Anim Sci, Lhasa 850023, Tibet, Peoples R China. [Zhang Yanming] Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Qinghai, Peoples R China. [Lin Hui] Tibet Bur Agr & Anim Husb, Lhasa 850000, Tibet, Peoples R China. RP Arthur, AD (通讯作者)，CSIRO Sustainable Ecosyst, GPO Box 284, Canberra, ACT 2601, Australia. EM Tony.Arthur@csiro.au; PechR@landcareresearch.co.nz; chris_davey@aapt.net.au; helloweisi@yahoo.com; zhangym@mail.nwipb.ac.cn TC 49 Z9 60 PD AUG PY 2008 VL 141 IS 8 BP 1972 EP 1981 DI 10.1016/j.biocon.2008.05.010 UT WOS:000259389600005 DA 2023-03-23 ER PT J AU Jin, HJ Yu, QH Wang, SL Lu, LZ AF Jin, Hui-jun Yu, Qi-hao Wang, Shao-ling Lue, Lan-zhi TI Changes in permafrost environments along the Qinghai-Tibet engineering corridor induced by anthropogenic activities and climate warming SO COLD REGIONS SCIENCE AND TECHNOLOGY DT Article AB The sensitive permafrost environments along the Qinghai-Tibet Engineering Corridor (QTEC) from Golmud to Lhasa are controlled by periglacial processes, geography, geocryology and the local climate. During the past 50 years, permafrost has been degrading at a rapid rate due to the combined influences of steadily increasing human activities and persistent climatic warming, and extensive accelerated degradation has been observed along the QTEC. In many locations, the surface vegetation and the top soils have been completely removed, or destroyed, and have led to significantly increased water and soil erosion, with extensive and serious environmental and engineering impacts. The vegetation along the QTEC is dominated by alpine grasslands and meadows. The alpine grasslands have a better capability for recovery from the damages than the meadows. At sections where the vegetation and soils were severely damaged, it will take 20-30 years for alpine grasslands to recover their ecological structures and biodiversity similar to that of the original conditions, whereas it will take 45-60 years for the alpine meadows. The environmental management and protection along the QTEC are urgent and important for the long-term stability of engineering foundations, and for the sustainable development on the Qinghai-Tibet Plateau (QTP). The proper protection and management requires the development of a non-interference plan and acceleration in the enactment and enforcement of environmental protection (laws, regulations and stipulations) based on an extensive and thorough understanding and practical rehabilitation techniques for disturbed or damaged permafrost environments. (c) 2007 Elsevier B.V. All rights reserved. C1 [Jin, Hui-jun; Yu, Qi-hao; Wang, Shao-ling; Lue, Lan-zhi] Chinese Acad Sci, State Key Lab Frozen Soils Engn, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Gansu, Peoples R China. RP Jin, HJ (通讯作者)，Chinese Acad Sci, State Key Lab Frozen Soils Engn, Cold & Arid Reg Environm & Engn Res Inst, 326 W Donggang Rd, Lanzhou 730000, Gansu, Peoples R China. EM hjjin@lzb.ac.cn; shaolingwang@yahoo.com TC 143 Z9 176 PD AUG PY 2008 VL 53 IS 3 BP 317 EP 333 DI 10.1016/j.coldregions.2007.07.005 UT WOS:000260040200008 DA 2023-03-23 ER PT J AU Miehe, G Mlehe, S Kaiser, K Liu, JQ Zhao, XQ AF Miehe, Georg Mlehe, Sabine Kaiser, Knut Liu Jianquan Zhao, Xinquan TI Status and dynamics of Kobresia pygmaea ecosystem on the Tibetan plateau SO AMBIO DT Article AB This paper provides information about the distribution, structure, and ecology of the world's largest alpine ecosystem, the Kobresia pygmaea pastures in the southeastern Tibetan plateau. The environmental importance of these Cyperaceae mats derives from the extremely firm turf, which protects large surfaces against erosion, including the headwaters of the Huang He, Yangtze, Mekong, Salween, and Brahmaputra. The emphasis of the present article is on the climate-driven evolution and recent dynamics of these mats under the grazing impact of small mammals and livestock. Considering pedological analyses, radiocarbon datings, and results from exclosure experiments, we hypothesize that the majority of K. pygmaea mats are human-induced and replace forests, scrub, and taller grasslands. At present, the carrying capacity is increasingly exceeded, and reinforced settlement of nomads threatens this ecosystem especially in its drier part, where small mammals become strong competitors with livestock and the removal of the turf is irreversible. Examples of rehabilitation measures are given. C1 [Miehe, Georg; Mlehe, Sabine; Kaiser, Knut] Univ Marburg, Fac Geog, D-35032 Marburg, Germany. [Liu Jianquan; Zhao, Xinquan] Chinese Acad Sci, NW Inst Plateau Biol, Xining 810008, Qinghai, Peoples R China. RP Miehe, G (通讯作者)，Univ Marburg, Fac Geog, Deutsch Str 10, D-35032 Marburg, Germany. EM miehe@staff.uni-marburg.de; sabine.miehe@gmx.net; knut.kaiser@staff.uni-marburg.de; ljqdxy@public.xn.qh.cn; xqzhao@public.xn.qh.cn TC 113 Z9 123 PD JUN PY 2008 VL 37 IS 4 BP 272 EP 279 DI 10.1579/0044-7447(2008)37[272:SADOTK]2.0.CO;2 UT WOS:000257637400006 DA 2023-03-23 ER PT J AU Li, Y Luo, T Lu, Q AF Li, Yonghua Luo, Tiangxing Lu, Qi TI Plant height as a simple predictor of the root to shoot ratio: Evidence from alpine grasslands on the Tibetan Plateau SO JOURNAL OF VEGETATION SCIENCE DT Article AB Question: Since increases in altitude and grazing intensity generally result in decreases in height growth of alpine grass-lands, plant height may integrate effects of environmental stress and grazing disturbance and provide better assessments of the variation in root: shoot ( R: S) biomass ratio than other variables. However, it is unclear if there is a general relationship between plant height and R: S ratio across grassland ecosystems. Such knowledge would be helpful for root biomass estimation in grasslands. Location: An altitudinal transect in the Gonghe Basin ( 2880-4040 m a.s.l.), northeast Tibetan plateau. Methods: We measured standing biomass both above-ground and below-ground, maximum plant height (MPH) and soil variables across 43 plots. Results: Climatic variables explained the variations in MPH and R: S ratio of undegraded grasslands better than soil variables (46-50% vs < 19%), while those of degraded grasslands generally showed insignificant correlations with climatic and soil variables. There was a general relationship between R: S ratio and MPH ( negative, R-2 = 0.76, P < 0.001) across degraded and undegraded grasslands. The relationship was used to predict R: S ratio in 13 additional plots in steppe grasslands of Inner Mongolia, and good agreement of expected and observed values has been found ( R-2 = 0.87, P < 0.001). Conclusions: MPH, that is relatively easy to measure, can be used to predict R: S ratio at plot to regional scales. It is promising to develop a new method for large-scale estimation of root biomass in grasslands using MPH and shoot biomass avoiding tedious procedures of physical measuring of above and below-ground biomass. C1 [Li, Yonghua; Luo, Tiangxing] Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100085, Peoples R China. [Lu, Qi] Chinese Acad Forestry, Beijing 100091, Peoples R China. RP Luo, T (通讯作者)，Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100085, Peoples R China. EM luotx@itpcas.ac.cn TC 36 Z9 45 PD APR PY 2008 VL 19 IS 2 BP 245 EP 252 DI 10.3170/2007-8-18365 UT WOS:000253120500011 DA 2023-03-23 ER PT J AU Wang, GX Li, YS Wang, YB Wu, QB AF Wang Genxu Li Yuanshou Wang Yibo Wu Qingbo TI Effects of permafrost thawing on vegetation and soil carbon pool losses on the Qinghai-Tibet Plateau, China SO GEODERMA DT Article AB Bearing a total organic carbon (TOC) content of 9.3-10.7 kg c/m(2), alpine grassland soils of the Qinghai-Tibet plateau's permafrost region bear a greater organic carbon pool than do grassland soils in other regions of China or than tropical savannah soils. The easily released light fraction organic carbon (LFOC) accounts for 34-54% of the TOC and is particularly enriched in the topsoil (0-0.10 in). The LFOC in the organic carbon pool of alpine cold meadow and alpine cold steppe soils decreased at exponential and quadratic rates, respectively, as the vegetative cover decreased. When the vegetative cover of alpine cold meadows decreased from > 80 dm(2)/m(2) to 60 dm(2)/m(2), the topsoil TOC and LFOC dropped by 20.4% and 38.4%, respectively. Similarly, when the vegetative cover of alpine cold meadow decreased from 50 dm(2)/m(2) to 30 dm(2)/m(2) and < 15 dm(2)/m(2), the topsoil LFOC content dropped by 60% and 86.7%, respectively. Under climatic warming, the degradation of permafrost and vegetation have resulted in serious soil organic carbon (SOC) loss from the carbon pool. Land cover changes that occurred between 1986 and 2000 are estimated to have resulted in a 1.8 Gg C (120 Mg C/yr) loss in SOC, and a concomitant 65% decrease in the LFOC, in the 0-0.30 in soil layer in the Qinghai-Tibet plateau's permafrost regions. Since the region's ecosystems are quite sensitive to global climate changes, if global warming persists, alpine cold grassland ecosystems are expected to further degrade. Hence, the influence of global climatic change on soil carbon emissions from alpine grasslands should receive more attention. (C) 2007 Elsevier B.V. All rights reserved. C1 [Wang Genxu] Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. [Wang Genxu; Wang Yibo] Lanzhou Univ, Coll Resources & Environm, Lanzhou 730000, Peoples R China. [Li Yuanshou; Wu Qingbo] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM gxwang@ns.lzb.ac.cn TC 134 Z9 155 PD JAN 15 PY 2008 VL 143 IS 1-2 BP 143 EP 152 DI 10.1016/j.geoderma.2007.10.023 UT WOS:000252586200014 DA 2023-03-23 ER PT J AU Long, RJ Ding, LM Shang, ZH Guo, XH AF Long, R. J. Ding, L. M. Shang, Z. H. Guo, X. H. TI The yak grazing system on the Qinghai-Tibetan plateau and its status SO RANGELAND JOURNAL DT Article AB Yaks are a multifunctional and dominant livestock species on the Qinghai-Tibetan plateau. The yak grazing system is a traditional transhumance system. Research is focussed on both understanding and improving the system. Development of local economies and the use of new knowledge from yak research and modern technology are improving the system. However, the Qinghai-Tibetan plateau ecosystem is becoming dysfunctional through adverse climate sequences, over-population and over-grazing. The Chinese Government has implemented regional projects to address these degradation problems. Several policies have recently been introduced to improve yak grazing management. This paper reviews current knowledge on the system and the options for improving and optimising the system. C1 [Long, R. J.; Ding, L. M.; Guo, X. H.] Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, Lanzhou 730020, Gansu, Peoples R China. [Long, R. J.; Shang, Z. H.] Lanzhou Univ, Grassland & Yak Res Ctr, Coll Pastoral Agr Sci & Technol, Lanzhou 730020, Gansu, Peoples R China. [Ding, L. M.; Guo, X. H.] Lanzhou Univ, Sch Life Sci, Minist Educ, Key Lab Arid & Grassland Ecol, Lanzhou 730000, Gansu, Peoples R China. RP Long, RJ (通讯作者)，Lanzhou Univ, Int Ctr Tibetan Plateau Ecosyst Management, Lanzhou 730020, Gansu, Peoples R China. EM longrj@lzu.edu.cn TC 94 Z9 128 PY 2008 VL 30 IS 2 BP 241 EP 246 DI 10.1071/RJ08012 UT WOS:000256384700006 DA 2023-03-23 ER PT J AU Han, WW Luo, YJ Du, GZ AF Han, Wenwu Luo, Yanjiang Du, Guozhen TI Effects of clipping on diversity and above-ground biomass associated with soil fertility on an alpine meadow in the eastern region of the Qinghai-Tibetan Plateau SO NEW ZEALAND JOURNAL OF AGRICULTURAL RESEARCH DT Article AB The objective of this research was to test the hypothesis that effects of different clipping regimes on diversity on an alpine meadow are due to soil fertility. Species richness should be greatest at an intermediate level of disturbance, e.g., clipping, since dominance is prevented and the pool of potential colonists is relatively large. We predict the effects of clipping on species richness, diversity and above-ground biomass based on the disturbance hypothesis. A natural pasture was used for the experiment that was a randomised complete block design with four levels of nutrient input annually from the 2001 growing season. During 2004, subplots were clipped to stubble heights of 2, 4 and 10 cm above the soil surface, with a control. Species richness declined to an average of 6 and 19 species per quadrat for the treatments that were heavily clipped twice, compared to an average of I I and 31 species per quadrat in the unclipped treatment receiving nutrient input of 120 g of fertiliser/m(2) and control plots, respectively. Species richness was not altered by the other clipping treatments at any nutrient level. Species richness declined in plots with the highest nutrient input and in control plots with heavy clipping twice, but species richness had no obvious changes in those plots receiving the intermediate level clipping at all nutrient levels. Available phosphorus increased significantly with increased nutrient addition, however soil pH decreased. Available nitrogen and organic matter did not change significantly with nutrient addition. The clipping regime contributed to the dominance of graminoids with increased nutrient input, and the dominant graminoids assimilated large amounts of available nitrogen and organic matter, which resulted in the minor changes in available nitrogen in soil. C1 Lanzhou Univ, Law Agr Technol Coll, Lanzhou 730000, Peoples R China. Chinese Acad Sci, Inst Tibetan Plateau Res, Nam Co Monitoring & Res Stn Multisphere Interact, Beijing 100085, Peoples R China. RP Du, GZ (通讯作者)，Lanzhou Univ, Dept Ecol, Tianshui Rd 222, Lanzhou 730000, Peoples R China. EM guozdu@lzu.edu.cn TC 9 Z9 19 PD SEP PY 2007 VL 50 IS 3 BP 361 EP 368 DI 10.1080/00288230709510304 UT WOS:000250474400010 DA 2023-03-23 ER PT J AU Wang, JF Wang, GX Wang, YB Li, YS AF Wang JunFeng Wang GenXu Wang YiBo Li YuanShou TI Influences of the degradation of swamp and alpine meadows on CO2 emission during growing season on the Qinghai-Tibet Plateau SO CHINESE SCIENCE BULLETIN DT Article AB CO2 emission fluxes of two types of ecosystem, swamp meadow and alpine meadow, in the Fenghuoshan region of the Qinghai-Tibet Plateau were studied by the static chamber-portable infrared chromatographic method. The results showed that there was large difference in the CO2 emission fluxes between the two ecosystems and in the same ecosystem of different degradation degrees. CO2 emission flux of the swamp meadow gradually decreased with increasing degradation degree, while that of the alpine meadow gradually increased with increasing degradation degree except in May. The CO2 emission flux of undegraded swamp meadow was 65.1%-80.3% higher than that of undegraded alpine meadow; and the CO2 emission flux of moderately degraded swamp meadow was 22.1%-67.5% higher than that of alpine meadow; but the CO2 emission flux of severely degraded alpine meadow was 14.3%-29.5% higher than that of swamp meadow. The soil moisture content and temperature in the upper 5 cm soil layer and above-ground biomass were significantly correlated with the CO2 emission fluxes and regarded as the main environment factors to control the CO2 emission. C1 Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Peoples R China. Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Wang, JF (通讯作者)，Lanzhou Univ, Coll Earth & Environm Sci, Lanzhou 730000, Peoples R China. EM wangjf2008@yahoo.com.cn TC 18 Z9 21 PD SEP PY 2007 VL 52 IS 18 BP 2565 EP 2574 DI 10.1007/s11434-007-0343-5 UT WOS:000249915500016 DA 2023-03-23 ER PT J AU Wang, GX Wang, YB Li, YS Cheng, HY AF Wang, Genxu Wang, Yibo Li, Yuanshou Cheng, Huiyan TI Influences of alpine ecosystem responses to climatic change on soil properties on the Qinghai-Tibet Plateau, China SO CATENA DT Article AB Alpine ecosystems are quite sensitive to global climatic changes. Drawing from two sets of remote sensing data (1986 and 2000) and field investigations, the ecological index method was used to document ecosystem changes in the Yangtze and Yellow River source regions of central Qinghai-Tibet. Although crucial to understanding alpine ecosystem responses to global climatic changes, and in assessing the potential for their rehabilitation, the impact of such changes on alpine soil characteristics, including structure, composition, water retention, as well as chemical and nutrient contents, is poorly understood. Over a 15-year period (1986-2000), climatic changes led to considerable degradation of alpine meadows and steppes. In the meadows, the surface layers of the soil became coarser, bulk density, porosity and saturated hydraulic conductivity rose, while water-holding capacity decreased. In comparison, steppe soils showed little changes in soil physical properties. Degradation of alpine ecosystems led to large losses in soil available Fe, Mn and Zn. Important losses in soil organic matter (SOM) and total nitrogen (TN) occurred in badly degraded ecosystems. Climate warming in the Qinghai-Tibet Plateau, caused by the impact of greenhouse gas, has resulted in changes of cold alpine ecosystem such as the significant alteration of the soil C and N cycles. (c) 2007 Elsevier B.V.. All rights reserved. C1 Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. Lanzhou Univ, Coll Resources & Envrironm, Lanzhou 730000, Peoples R China. Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM gxwang@ns.lzb.ac.cn TC 176 Z9 204 PD AUG 1 PY 2007 VL 70 IS 3 BP 506 EP 514 DI 10.1016/j.catena.2007.01.001 UT WOS:000248715200024 DA 2023-03-23 ER PT J AU Pech, RP Jiebu Arthur, AD Zhang, YM Hui, L AF Pech, Roger P. Jiebu Arthur, Anthony D. Zhang Yanming Hui, Lin TI Population dynamics and responses to management of plateau pikas Ochotona curzoniae SO JOURNAL OF APPLIED ECOLOGY DT Article AB 1. Plateau pikas Ochotona curzoniae are considered a pest species on the Tibetan Plateau because they compete with livestock for forage and their burrowing could contribute to soil erosion. The effectiveness of pest control programmes in Tibet has not been measured, and it is not known whether changes in livestock management have exacerbated problems with plateau pikas or compromised their control. This study measured the impact of control programmes and livestock management for forage conservation on populations of plateau pikas in alpine meadow in Naqu District, central Tibet, during 2004 and 2005. 2. Current techniques for controlling plateau pikas in spring cause large reductions in abundance, but high density-dependent rates of increase result in no differences between treated and untreated populations by the following autumn. Rates of increase from spring to autumn are not influenced by standing plant biomass or concurrent grazing by yaks Bos grunniens and Tibetan sheep Ovis aries. 3. In autumn there was significantly lower biomass outside fenced areas with year-round livestock grazing compared with inside fenced areas with equivalent or higher numbers of plateau pikas but predominantly winter grazing by livestock. Inside fenced areas, control of plateau pikas in spring produced no detectable effect on standing plant biomass at the end of the following summer compared with uncontrolled populations of plateau pikas. 4. Regardless of their initial density, populations of plateau pikas declined rapidly over winter outside fenced areas where there was very low standing plant biomass in autumn. However, inside fenced areas with higher plant biomass in autumn, low-density populations of plateau pikas declined more slowly than high-density populations. 5. Synthesis and applications. Current control programmes have limited effect because populations of plateau pikas can recover in one breeding season. There was no apparent increase in forage production in areas where plateau pikas were controlled. However, plateau pikas appear to benefit from changes in grazing management, with low-density populations declining less over winter inside fenced areas than elsewhere. It was not evident that control programmes are warranted or that they will improve the livelihoods of Tibetan herders. C1 CSIRO Sustainable Ecosyst, Canberra, ACT 2601, Australia. Tibet Acad Agr & Anim Sci, Tibet 850023, Peoples R China. Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Qinghai, Peoples R China. Bur Agr & Anim Husb, Tibet 850000, Peoples R China. RP Pech, RP (通讯作者)，Landcare Res, POB 40, Lincoln, New Zealand. EM PechR@landcareresearch.co.nz TC 81 Z9 109 PD JUN PY 2007 VL 44 IS 3 BP 615 EP 624 DI 10.1111/j.1365-2664.2007.01287.x UT WOS:000246621700016 DA 2023-03-23 ER PT J AU Wang, CT Long, RJ Wang, QJ Ding, LM Wang, MP AF Wang, Chang Ting Long, Rui Jun Wang, Qi Ji Ding, Lu Ming Wang, Mei Ping TI Effects of altitude on plant-species diversity and productivity in an alpine meadow, Qinghai-Tibetan plateau SO AUSTRALIAN JOURNAL OF BOTANY DT Article AB During the growing seasons of 2002 and 2003, biomass productivity and diversity were examined along an altitudinal transect on the south-western slope of Beishan Mountain, Maqin County (33 degrees 43'-35 degrees 16'N, 98 degrees 48'-100 degrees 55'E), Qinghai-Tibetan Plateau. Six altitudes were selected, between 3840 and 4435 m. Soil organic matter, soil available N and P and environmental factors significantly affected plant-species diversity and productivity of the alpine meadows. Aboveground biomass declined significantly with increasing altitude (P < 0.05) and it was positively and linearly related to late summer soil-surface temperature. Belowground biomass (0 - 10-cm depth) was significantly greater at the lowest and highest altitudes than at intermediate locations, associated with water and nutrient availabilities. At each site, the maximum belowground biomass values occurred at the beginning and the end of the growing seasons (P < 0.05). Soil organic matter content, and available N and P were negatively and closely related to plant diversity (species richness, Shannon-Wiener diversity index, and Pielou evenness index). C1 Chinese Acad Sci, NW Plateau Inst Biol, Xining 810008, Peoples R China. Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China. Lanzhou Univ, Coll Pastoral Agr Sci & Technol, Ctr Tibetan Grassland & Yak Studies, Lanzhou, Peoples R China. RP Long, RJ (通讯作者)，Chinese Acad Sci, NW Plateau Inst Biol, Xining 810008, Peoples R China. EM longruijun@sina.com TC 57 Z9 76 PY 2007 VL 55 IS 2 BP 110 EP 117 DI 10.1071/BT04070 UT WOS:000244949800003 DA 2023-03-23 ER PT J AU Wang, JS Hu, J Tang, DH Liu, XH Zhen, Z AF Wang, Jianshe Hu, Jin Tang, Daihua Liu, Xinhou Zhen, Zhen TI Oleic acid (OA)-modified LaF3 : Er, Yb nanocrystals and their polymer hybrid materials for potential optical-amplification applications SO JOURNAL OF MATERIALS CHEMISTRY DT Article AB Oleic acid (OA)-modified LaF3 : Er, Yb nanocrystals (NCs) have been prepared and investigated. The OA-capped nanocrystals have a nearly spherical shape with a mean diameter of 7 nm and show excellent dispersibility in common organic solvents and a PMMA matrix. A 0.25 g ml(-1) transparent colloidal solution in toluene can be obtained. The resulting nanocrystal-polymer hybrid materials exhibit strong emission around the 1550 nm telecommunication window when excited at 980 nm and are promising materials for polymer-based optical waveguide amplifiers. C1 Chinese Acad Sci, Lab Organ Optoelect Funct Mat & Mol Engn, Tech Inst Phys & Chem, Beijing 100080, Peoples R China. Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China. RP Zhen, Z (通讯作者)，Chinese Acad Sci, Lab Organ Optoelect Funct Mat & Mol Engn, Tech Inst Phys & Chem, Beijing 100080, Peoples R China. EM zhenz@mail.ipc.ac.cn TC 91 Z9 94 PY 2007 VL 17 IS 16 BP 1597 EP 1601 DI 10.1039/b617754a UT WOS:000245599400008 DA 2023-03-23 ER PT J AU Zhang, YQ Tang, YH Jiang, J Yang, YH AF Zhang YongQinag Tang YanHong Jiang Jie Yang YongHai TI Characterizing the dynamics of soil organic carbon in grasslands on the Qinghai-Tibetan Plateau SO SCIENCE IN CHINA SERIES D-EARTH SCIENCES DT Article AB Carbon dynamics of grasslands on the Qinghai-Tibetan Plateau may play an important role in regional and global carbon cycles. The CENTURY model (Version 4.5) is used to examine temporal and spatial variations of soil organic carbon (SOC) in grasslands on the Plateau for the period from 1960 to 2002. The model successfully simulates the dynamics of aboveground carbon and soil surface SOC at the soil depth of 0-20 cm and the simulated results agree well to the measurements. Examination of SOC for eight typical grasslands shows different patterns of temporal variation in different ecosystems in 1960-2002. The extent of temporal variation increases with the increase of SOC of ecosystem. SOC increases first and decreases quickly then during the period from 1990 to 2000. Spatially, SOC density obtained for the equilibrium condition declines gradually from the southeast to the northwest on the plateau and showed a high heterogeneity in the eastern plateau. The results suggest that (i) SOC density in the alpine grasslands shows remarkable response to climate change during the 42 years, and (ii) the net carbon exchange rate between the alpine grassland ecosystems and the atmosphere increases from 1990 to 2000 as compared with that before 1990. C1 Natl Inst Environm Studies, Div Environm Biol, Tsukuba, Ibaraki 3058506, Japan. Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. Chinese Acad Sci, Res Ctr Agr Resources, Inst Genet & Dev Biol, Shijiazhuang 050021, Peoples R China. RP Zhang, YQ (通讯作者)，Natl Inst Environm Studies, Div Environm Biol, Tsukuba, Ibaraki 3058506, Japan. EM zhangyq@igsnrr.ac.cn TC 45 Z9 61 PD JAN PY 2007 VL 50 IS 1 BP 113 EP 120 DI 10.1007/s11430-007-2032-2 UT WOS:000244621300012 DA 2023-03-23 ER PT J AU Zhou, HK Tang, YH Zhao, XQ Zhou, L AF Zhou, Huakun Tang, Yanhong Zhao, Xinquan Zhou, Li TI Long-term grazing alters species composition and biomass of a shrub meadow on the Qinghai-Tibet Plateau SO PAKISTAN JOURNAL OF BOTANY DT Article AB Livestock grazing has long been the most widespread land use on the Qinghai-Tibet Plateau, one of the world's highest ecosystems. However, there has been increasing concern during recent decades because of the rapid increase in livestock numbers. To assess the possible influences of grazing on the vast grassland, a long-term grazing experiment in a shrub meadow on the northern Qinghai-Tibet Plateau was carried out. The experiment included five treatments with different stocking rates and one non-grazing (N) treatment. After 17 years of grazing, treatment differences were clear. The species composition differed markedly between grazing intensities, with a decrease in palatable grass species and an increase in unpalatable forbs at higher grazing intensities. The species richness and species diversity, however, were not significantly different between treatments. Vegetation height decreased significantly at higher grazing intensities. Total above,ground biomass declined considerably and the biomass of forbs increased significantly under the higher grazing intensities. The amount of litter was significantly lower under the higher grazing intensities. The results suggest that long-term grazing alters the species composition, vegetation height and biomass production of the alpine grassland ecosystem without significantly changing species richness. C1 Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China. Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Peoples R China. Natl Inst Environm Studies, Tsukuba, Ibaraki 3058506, Japan. RP Zhou, HK (通讯作者)，Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China. TC 39 Z9 60 PD DEC PY 2006 VL 38 IS 4 BP 1055 EP 1069 UT WOS:000244728800018 DA 2023-03-23 ER PT J AU Wang, GX Li, YS Wu, QB Wang, YB AF Wang Genxu Li Yuanshou Wu Qingbai Wang Yibo TI Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau SO SCIENCE IN CHINA SERIES D-EARTH SCIENCES DT Article AB Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the permafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 28.11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively serious degradation. Furthermore, from the angles of grassland coverage and biological production the variation characteristics of high-cold ecosystems in different representative regions and different geomorphologic units under different climatic conditions were quantitatively assessed. In the future, adopting effective measures to protect permafrost is of vital importance to maintaining the stability of permafrost engineering and alpine cold ecosystems in the plateau. C1 Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. Lanzhou Univ, Resource & Environm Sch, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM gxwang@lzb.ac.cn TC 128 Z9 150 PD NOV PY 2006 VL 49 IS 11 BP 1156 EP 1169 DI 10.1007/S11430-006-1156-0 UT WOS:000242923300004 DA 2023-03-23 ER PT J AU Yang, JP Ding, YJ Chen, RS AF Yang, Jianping Ding, Yongjian Chen, Rensheng TI Spatial and temporal of variations of alpine vegetation cover in the source regions of the Yangtze and Yellow Rivers of the Tibetan Plateau from 1982 to 2001 SO ENVIRONMENTAL GEOLOGY DT Article AB Spatial and temporal variations in alpine vegetation cover have been analyzed between 1982 and 2001 in the source regions of the Yangtze and Yellow Rivers on the Tibetan Plateau. The analysis was done using a calibrated-NDVI (Normalized Difference Vegetative Index) temporal series from NOAA-AVHRR images. The spatial and temporal resolutions of images are 8 km and 10 days, respectively. In general, there was no significant trend in alpine vegetation over this time period, although it continued to degrade severely in certain local areas around Zhaling and Eling Lakes, in areas north of these lakes, along the northern foot of Bayankala Mountain in the headwaters of the Yellow River, in small areas in the Geladandong region, in a few places between TuoTuohe and WuDaoliang, and in the QuMalai and Zhiduo belts in the headwaters of the Yangtze River. Degradation behaves as vegetation coverage reduced, soil was uncovered in local areas, and over-ground biomass decreased in grassland. The extent of degradation ranges from 0 to 20%. Areas of 3x3 pixels centered on Wudaoliang, TuoTuohe, QuMalai, MaDuo, and DaRi meteorological stations were selected for statistical analysis. The authors obtained simple correlations between air temperature, precipitation, ground temperature and NDVI in these areas and constructed multivariate statistical models, including and excluding the effect of ground temperature. The results show that vegetation cover is sensitive to variations in temperature, and especially in the ground temperature at depths of similar to 40 cm. Permafrost is distributed widely in the study area. The resulting freezing and thawing are related to ground temperature change, and also affect the soil moisture content. Thus, degradation of permafrost directly influences alpine vegetation growth in the study area. C1 Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Yang, JP (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. EM jianping@ns.lzb.ac.cn TC 58 Z9 81 PD JUN PY 2006 VL 50 IS 3 BP 313 EP 322 DI 10.1007/s00254-006-0210-8 UT WOS:000238170600002 DA 2023-03-23 ER PT J AU Wang, GX Wang, YB Qian, J Wu, QB AF Wang Genxu Wang Yibo Qian Ju Wu Qingbo TI Land cover change and its impacts on soil C and N in two watersheds in the center of the Qinghai-Tibetan Plateau SO MOUNTAIN RESEARCH AND DEVELOPMENT DT Article AB The responses of the ecosystems along the 0 degrees C mean annual isotherm to global climate change are intense and involve significant changes in land cover at the water shed scale. This paper evaluates changes in land cover in the center of Qinghai-Tibet, the headwater region of the Yangtze and Yellow Rivers, on the basis of two sets of remote sensing data (1986 and 2000) and field investigations. Over a period of 15 years, 23% and 34% of alpine cold swamp were recently turned into alpine cold meadow or alpine cold steppe, and decreased in area by 25.9% and 42.7% in the headwater areas of the Yellow and Yangtze Rivers, respectively. Moreover, more than 20% of high-coverage alpine cold meadow and alpine cold steppe were converted to lower-coverage alpine cold meadow (vegetation coverage > 80%) and alpine cold steppe (vegetation coverage > 50%). Desertified land increased by 18.4% (bare rocks and sparse land) and 31.1% (sandy land) in the headwater area of the Yellow River and by 17.8%-18.5% in the headwater area of the Yangtze River. Land cover change in this region involves a complex transition between land cover types, which have a great influence on soil nutrients and the soil organic carbon (SOC) pool. Land cover changes in the study area over the 15-year study period led to the loss of 336.6 Gg of SOC, of which 61.6% were lost by alpine cold swamp transformation, and a total nitrogen (N) loss of 26.9 Gg, of which 81.9% occurred in the headwater area of the Yangtze River. The changes in the carbon and nitrogen cycles have serious implications for greenhouse gas emissions due to land cover change caused by climate warming in the Qinghai-Tibetan Plateau. C1 Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. Lanzhou Univ, Coll Resources & Environm, Lanzhou 730000, Peoples R China. Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Inst Mt Hazards & Environm, Chengdu 610041, Peoples R China. EM gxwang@ns.lzb.ac.cn; yibo_wang@163.com; qianju@lzu.edu.cn; qbwu@lzb.ac.cn TC 14 Z9 19 PD MAY PY 2006 VL 26 IS 2 BP 153 EP 162 UT WOS:000238660700012 DA 2023-03-23 ER PT C AU Ke, CQ AF Ke, Chang-Qing BE Gao, W Ustin, SL TI Land cover change in Qumar River valley SO REMOTE SENSING AND MODELING OF ECOSYSTEMS FOR SUSTAINABILITY III SE Proceedings of SPIE DT Proceedings Paper CT Conference on Remote Sensing and Modeling of Ecosystems for Sustainability III CY AUG 14-16, 2006 CL San Diego, CA AB One of the Yangtze River sources, Qumar River valley was selected as the research area. Landsat Thematic Mapper (TM) imagery were very useful in detecting and monitoring the land cover change, especially in the desolate and bad physical environment region like Tibetan Plateau. In our work TM images in 1994 and land cover map in 1980s were selected to detect and monitor the land cover change. The satellite images were calibrated, registered and georeferenced, then classified and visually interpreted. Ancillary data such as were used to assist the satellite image classification and interpretation. Seven land cover types were obtained, that is, residential area, meadow steppe, alpine meadow, alpine steppe, water surface, exposed rock and desert land. The statistical results of every class land cover type indicated that the desert expanded significantly, about 194km(2), a very big number. The climatic change maybe is the main reason, but the human activity, for example, digging gold in the northwest of this area, is also maybe an important affecting factor. Secondly, the meadow steppe distributed in the low reaches of Qumar River decreased significantly, its change maybe is relevant to climatic change. The variation trend of other land cover type is not significant. All of this showed the significant degeneration of ecological environment of the source of Yangtze River. C1 Nanjing Univ, Sch Geog & Oceanog, Nanjing 210093, Peoples R China. RP Ke, CQ (通讯作者)，Nanjing Univ, Sch Geog & Oceanog, Nanjing 210093, Peoples R China. EM kecq2000@sohu.com TC 0 Z9 0 PY 2006 VL 6298 AR 62981R DI 10.1117/12.677337 UT WOS:000243026400050 DA 2023-03-23 ER PT C AU Yang, YZ Feng, ZM Liu, DW Zhang, J AF Yang, Yanzhao Feng, Zhiming Liu, Dengwei Zhang, Jing GP IEEE TI The Spatial-temporal Change of Grassland in Qinghai-Tibet Plateau SO 2006 IEEE INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, VOLS 1-8 SE IEEE International Symposium on Geoscience and Remote Sensing IGARSS DT Proceedings Paper CT IEEE International Geoscience and Remote Sensing Symposium (IGARSS) CY JUL 31-AUG 04, 2006 CL Denver, CO AB Land use change has important consequences for global and regional climates. Qing-hai Tibet Plateau is regarded as "the tower of China". The most important land use is pasture in Qing-hai Plateau, which covers about 50% of the total land area. Thus, the sustainable management of the grassland is not only closely related to the survival and development of the herdsmen on the plateau, but also to the environmental protection of China. The aims of this study are to characterize and identify the grassland change of Shannan prefecture, located in south of the Qinghai-Tibet Plateau, during the recent decade, and put forward management countermeasure of future land use. Grassland-cover change trends were investigated using land-cover maps derived from Moderate Resolution Imaging Spectrometer (MODIS) data in 2001 and 1:100,000 image from grassland map of China. Unsupervised and supervised classification methods, incorporating with Digital elevation model (DEM), were used to classify the MODIS image. The results showed that in general, the grassland area in Shannan prefecture has degraded in the last decades, and more than 9.15 percent grassland has degraded just in the last 15 years. The degradation area of alpine meadow was the largest among all kinds of grassland. The most serious degradation regions were located in north of Shannan Prefecture. C1 [Yang, Yanzhao; Feng, Zhiming; Liu, Dengwei; Zhang, Jing] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. RP Yang, YZ (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. TC 1 Z9 2 PY 2006 BP 3099 EP 3102 DI 10.1109/IGARSS.2006.795 UT WOS:000260989401387 DA 2023-03-23 ER PT J AU Hirota, M Tang, YH Hu, QW Kato, T Hirata, S Mo, WH Cao, GM Mariko, S AF Hirota, M Tang, YH Hu, QW Kato, T Hirata, S Mo, WH Cao, GM Mariko, S TI The potential importance of grazing to the fluxes of carbon dioxide and methane in an alpine wetland on the Qinghai-Tibetan Plateau SO ATMOSPHERIC ENVIRONMENT DT Article AB To assess the impact of livestock grazing on the emission of greenhouse gases from grazed wetlands, we examined biomass growth of plants, CO2 and CH4 fluxes under grazing and non-grazing conditions on the Qinghai-Tibetan Plateau wetland. After the grazing treatment for a period of about 3 months, net ecosystem CO2 uptake and aboveground biomass were significantly smaller, but ecosystem CH4 emissions were remarkably greater, under grazing conditions than under non-grazing conditions. Examination of the gas-transport system showed that the increased CH4 emissions resulted from mainly the increase of conductance in the gas-transport system of the grazed plants. The sum of global warming potential, which was estimated from the measured CO2 and CH4 fluxes, was 5.6- to 11.3-fold higher under grazing conditions than under non-grazing conditions. The results suggest that livestock grazing may increase the global warming potential of the alpine wetlands. (c) 2005 Elsevier Ltd. All rights reserved. C1 Natl Inst Environm Studies, Tsukuba, Ibaraki 3058506, Japan. CAS, NW Plateau Inst Biol, Xining 810001, Peoples R China. Frontier Res Ctr Global Change, Kanazawa Ku, Yokohama, Kanagawa 236001, Japan. Univ Tsukuba, Grad Sch Life & Environm Sci, Tsukuba, Ibaraki 3058572, Japan. Univ Tsukuba, Inst Biol Sci, Tsukuba, Ibaraki 3058572, Japan. RP Hirota, M (通讯作者)，Natl Inst Environm Studies, Onogawa 16-2, Tsukuba, Ibaraki 3058506, Japan. EM hirota.mitsuru@nies.go.jp TC 43 Z9 67 PD SEP PY 2005 VL 39 IS 29 BP 5255 EP 5259 DI 10.1016/j.atmosenv.2005.05.036 UT WOS:000232434900004 DA 2023-03-23 ER PT J AU Klein, JA Harte, J Zhao, XQ AF Klein, JA Harte, J Zhao, XQ TI Dynamic and complex microclimate responses to warming and grazing manipulations SO GLOBAL CHANGE BIOLOGY DT Article AB Synthesis efforts that identify patterns of ecosystem response to a suite of warming manipulations can make important contributions to climate change science. However, cross-study comparisons are impeded by the paucity of detailed analyses of how passive warming and other manipulations affect microclimate. Here we document the independent and combined effects of a common passive warming manipulation, open-top chambers (OTCs), and a simulated widespread land use, clipping, on microclimate on the Tibetan Plateau. OTCs consistently elevated growing season averaged mean daily air temperature by 1.0-2.0 degrees C, maximum daily air temperature by 2.1-7.3 degrees C and the diurnal air temperature range by 1.9-6.5 degrees C, with mixed effects on minimum daily air temperature, and mean daily soil temperature and moisture. These OTC effects on microclimate differ from reported effects of a common active warming method, infrared heating, which has more consistent effects on soil than on air temperature. There were significant interannual and intragrowing season differences in OTC effects on microclimate. For example, while OTCs had mixed effects on growing season averaged soil temperatures, OTCs consistently elevated soil temperature by approximately 1.0 degrees C early in the growing season. Nonadditive interactions between OTCs and clipping were also present: OTCs in clipped plots generally elevated air and soil temperatures more than OTCs in nonclipped plots. Moreover, site factors dynamically interacted with microclimate and with the efficacy of the OTC manipulations. These findings highlight the need to understand differential microclimate effects between warming methods, within warming method across ecosystem sites, within warming method crossed with other treatments, and within sites over various timescales. Methods, sites and scales are potential explanatory variables and covariables in climate warming experiments. Consideration of this variability among and between experimental warming studies will lead to greater understanding and better prediction of ecosystem response to anthropogenic climate warming. C1 Univ Calif Berkeley, Div Ecosyst Sci, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA. Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Peoples R China. RP Klein, JA (通讯作者)，Colorado State Univ, Natl Resource Ecol Lab, A206 NESB, Ft Collins, CO 80523 USA. EM jklein@nrel.colostate.edu TC 95 Z9 127 PD SEP PY 2005 VL 11 IS 9 BP 1440 EP 1451 DI 10.1111/j.1365-2486.2005.00994.x UT WOS:000231396700004 DA 2023-03-23 ER PT J AU Wang, WY Wang, QJ Wang, CY Shi, HL Li, Y Wang, G AF Wang, WY Wang, QJ Wang, CY Shi, HL Li, Y Wang, G TI The effect of land management on carbon and nitrogen status in plants and soils of alpine meadows on the Tibetan plateau SO LAND DEGRADATION & DEVELOPMENT DT Article AB Large-scale grassland rehabilitation has been carried out on the severely degraded lands of the Tibetan plateau. The grasslands created provide a useful model for evaluating the recovery of ecosystem properties. The purposes of this research were: (1) to examine the relative influence of various rehabilitation practices on carbon and nitrogen in plants and soils in early secondary succession; and (2) to evaluate the degree to which severely degraded grassland altered plant and soil properties relative to the non-disturbed native community. The results showed: (1) The aboveground tissue C and N content in the control were 105-97 g m(-2) and 3.356gm(-2), respectively. The aboveground tissue C content in the mixed seed treatment, the single seed treatment, the natural recovery treatment and the severely degraded treatment was 137 per cent, 98 per cent, 49 per cent and 38 per cent, respectively, of that in the control. The corresponding aboveground tissue N content was 109 per cent, 84 per cent, 60 per cent and 47 per cent, respectively, of that in the control. (2) Root C and N content in 0-20 cm depths of the control had an 2 2 average 1606 gm(-2) and 30-36 gm(-2) respectively. Root C and N content in the rehabilitation treatments were in the range of 26-36 per cent and 35-53 per cent, while those in the severely degraded treatment were only 17 per cent and 26 per cent of that in the control. (3) In the control the average soil C and N content at 0-20 cm was 11307 gm(-2) and 846 gm(-2), respectively. Soil C content in the uppermost 20 cm in the seeded treatments, the natural recovery treatment and the severely degraded treatment was 67 per cent, 73 per cent and 57 per cent, respectively, while soil N content in the uppermost 20cm was 72 per cent, 82 per cent and 79 per cent, respectively, of that in the control. The severely degraded land was a major C source. Restoring the severely degraded lands to perennial vegetation was an alternative approach to sequestering C in former degraded systems. N was a limiting factor in seeding grassland. It is necessary for sustainable utilization of seeding grassland to supply extra N fertilizer to the soil or to add legume species into the seed mix. Copyright (c) 2005 John Wiley & Sons, Ltd. C1 Lanzhou Univ, Dept Biol, Lanzhou 710000, Gansu, Peoples R China. Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Qinghai, Peoples R China. Qinghai Normal Univ, Dept Biol, Xining 810008, Qinghai, Peoples R China. RP Wang, G (通讯作者)，Lanzhou Univ, Dept Biol, Lanzhou 710000, Gansu, Peoples R China. EM wangwy02@st.lzu.edu.cn TC 41 Z9 53 PD SEP-OCT PY 2005 VL 16 IS 5 BP 405 EP 415 DI 10.1002/ldr.661 UT WOS:000232823500001 DA 2023-03-23 ER PT J AU Xu, LL Zhang, XZ Shi, PL Yu, GR AF Xu, LL Zhang, XZ Shi, PL Yu, GR TI Establishment of apparent quantum yield and maximum ecosystem assimilation on Tibetan Plateau alpine meadow ecosystem SO SCIENCE IN CHINA SERIES D-EARTH SCIENCES DT Article AB The alpine meadow is widely distributed on the Tibetan Plateau with an area of about 1.2X 10(6) km(2). Damxung County, located in the hinterland of the Tibetan Plateau, is the place covered with this typical vegetation. An open-path eddy covariance system was set up in Damxung rangeland station to measure the carbon flux of alpine meadow from July to October, 2003. The continuous carbon flux data were used to analyze the relationship between net ecosystem carbon dioxide exchange (NEE) and photosynthetically active radiation (PAR), as well as the seasonal patterns of apparent quantum yield (a) and maximum ecosystem assimilation (P-max). Results showed that the daytime NEE fitted fairly well with the PAR in a rectangular hyperbola function, with a declining in the order of peak growth period (0.0244 mu molCO(2) . mu mol(-1) PAR) > early growth period > seed maturing period > withering period (0.0098 mu molCO(2) . mu mol(-1) PAR). The Pmx did not change greatly during the first three periods, with an average of 0.433 MgCO2 . m(-2) . s(-1), i.e. 9.829 mu molCO(2) . m(-2) . s(-1). However, during the withering period, Fmax was only 0.35 MgCO2 . m(-2) . s(-1), i.e. 7.945 mu molCO(2) . m(-2) . s(-1). Compared with other grassland ecosystems, the a of the Tibetan Plateau alpine meadow ecosystem was much lower. C1 Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China. RP Xu, LL (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM xull@igsnrr.ac.cn TC 10 Z9 26 PD APR PY 2005 VL 48 SU 1 BP 141 EP 147 DI 10.1360/05zd0014 UT WOS:000229942300014 DA 2023-03-23 ER PT J AU Wei, XH Dong, SK Long, RJ Hu, ZZ Wang, GX AF Wei, XH Dong, SK Long, RJ Hu, ZZ Wang, GX TI Effect of annual weeds on the growth of perennial grass mixtures in the alpine region of the Qinghai-Tibetan Plateau SO NEW ZEALAND JOURNAL OF AGRICULTURAL RESEARCH DT Article AB In the alpine region of the Tibetan Plateau, five perennial grass cultivars, Bromus inermis (B), Elymus nutans (E), Clinelymus nutans (C), Agropyron cristatum (A), and Poa crymophila (P) were combined into nine communities with different compositions and ratios, B+C, E+A, B+E+A, E+B+C,C+E+A,B+E+C+A,B+C+A+P,B+E+A+P and E+C+A+P. Each combination was sown in six 10 X 10 m plots with three hand-weeded plots and three natural-growing plots in a completely randomised design in 1998. A field experiment studied the performance of these perennial grass combinations under the competitive interference of annual weeds in 3 consecutive years from 1998 to 2000. The results showed that annual weeds occupied more space and suppressed the growth of the grasses due to earlier germination and quicker growth in the establishment year, but this pattern changed in the second and third years. Leaf area indexes (LAIs) of grasses were greatly decreased by the competitive interference of weeds, and the negative effect of weeds on LAIs of grasses declined and stabilised in the second and third years. E+B+C, B+E+C+A, and B+E+A+P possessed relatively higher LAIs (P < 0.05) among all grass combinations and their LAIs were close to five when the competitive interference of weeds was removed. Grasses were competitively inferior to weeds in the establishment year, although their competitive ability (aggressivities) increased throughout the growing season. In the second and third years, grasses were competitively superior to weeds, and their competitive ability decreased from May until August and increased in September. Dry matter (DM) yields of grasses were reduced by 29.8-74.1% in the establishment year, 11.0-64.9% in the second year, and 16.0-55.8% in the third year by the competitive interference of weeds. B+E+C+A and B+E+A+P can produce around 14 t/ha of DM yields, significantly higher (P < 0.05) than the production of the other grass combinations in the second and third years after the competitive interference of weeds was removed. It was preliminarily concluded that removal of competitive interference of weeds increased the LAIs of all grass swards and improved the light interception of grasses, thus promoting the production of perennial grass pastures. The germination stage of the grasses in the establishment year was the critical period for weeding and suppression of weeds should occur at an early stage of plant growth. The grass combinations of B+E+C+A and B+E+A+P were productive and can be extensively established in the alpine regions of the Tibetan Plateau. Two or three growing seasons will be needed before determining success of establishment of grass mixtures under the alpine conditions of the Tibetan Plateau. C1 Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. Lanzhou Univ, Key Lab Arid Agroecol, Minist Educ, Lanzhou 730000, Peoples R China. Gansu Agr Univ, Sch Life Sci & Technol, Grassland Sci Coll, Lanzhou 730070, Peoples R China. Chinese Acad Sci, NW Plateau Inst Biol, Xining 810001, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm, Beijing 100875, Peoples R China. EM DSK@irs.bnu.edu.cn TC 0 Z9 1 PD MAR PY 2005 VL 48 IS 1 BP 75 EP 82 UT WOS:000229010700009 DA 2023-03-23 ER PT J AU Klein, JA Harte, J Zhao, XQ AF Klein, JA Harte, J Zhao, XQ TI Experimental warming causes large and rapid species loss, dampened by simulated grazing, on the Tibetan Plateau SO ECOLOGY LETTERS DT Article AB We investigated the independent and combined effects of experimental warming and grazing on plant species diversity on the north-eastern Tibetan Plateau, a region highly vulnerable to ongoing climate and land use changes. Experimental warming caused a 26-36% decrease in species richness, a response that was generally dampened by experimental grazing. Higher species losses occurred at the drier sites where N was less available. Moreover, we observed an indirect effect of climate change on species richness as mediated by plant-plant interactions. Heat stress and warming-induced litter accumulation are potential explanations for the species' responses to experimental warming. This is the first reported experimental evidence that climate warming could cause dramatic declines in plant species diversity in high elevation ecosystems over short time frames and supports model predictions of species losses with anthropogenic climate change. C1 Univ Calif Berkeley, Dept Environm Sci Policy & Management, Div Ecosyst Sci, Berkeley, CA 94720 USA. Chinese Acad Sci, NW Plateau Inst Biol, Xining, Qinghai, Peoples R China. RP Klein, JA (通讯作者)，Colorado State Univ, Nat Resource Ecol Lab, B226 NESB, Ft Collins, CO 80523 USA. EM jklein@nrel.colostate.edu TC 383 Z9 490 PD DEC PY 2004 VL 7 IS 12 BP 1170 EP 1179 DI 10.1111/j.1461-0248.2004.00677.x UT WOS:000225078000007 DA 2023-03-23 ER PT J AU Dong, SK Kang, MY Hu, ZZ Long, R Pu, XP AF Dong, SK Kang, MY Hu, ZZ Long, R Pu, XP TI Performance of cultivated perennial grass mixtures under different grazing intensities in the alpine region of the Qinghai-Tibetan Plateau SO GRASS AND FORAGE SCIENCE DT Article AB In 1998, seeds of four cultivated native perennial grasses, Bromus inermis (B), Clinelymus nutans (C), Elymus nutans (E) and Agropyron cristatum (A), were sown as mixtures with different seed rates in three combinations (B + C, B + E + A and B + E + C + A) in a field study in the north-eastern part of the Qinghai-Tibetan Plateau, China. A grazing experiment was conducted in 2000 to investigate the performance of these grass mixtures at leaf, plant and sward scales under different grazing intensities (GI). Four GIs, expressed as the proportion of herbage consumed by Tibetan lambs in relation to the available biomass (IP), were applied in the summer: no grazing, and 0.30, 0.50 and 0.70 of IP. Tiller numbers of the grasses increased and leaf photosynthetic rate, sward leaf area index (LAI) and herbage mass declined with increase in GI. No effect of GI on specific leaf area was observed. Interactions between GI and grass mixtures on the dynamics of species composition, swards' LAI and herbage mass were found. Large fluctuations in species composition with different GIs showed the poor species compatibility and sward persistence of these grass mixtures under high GI by sheep. C1 Beijing Normal Univ, Sch Environm Sci, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. Gansu Agr Univ, Grassland Sci Coll, Lanzhou, Peoples R China. Beijing Normal Univ, Coll Resources Sci & Technol, Beijing 100875, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Sch Environm Sci, State Key Lab Water Environm Simulat, Beijing 100875, Peoples R China. EM dongshikui@sina.com TC 17 Z9 22 PD SEP PY 2004 VL 59 IS 3 BP 298 EP 306 DI 10.1111/j.1365-2494.2004.00429.x UT WOS:000223662400010 DA 2023-03-23 ER PT J AU Wang, XH Fu, XF AF Wang, XH Fu, XF TI Sustainable management of alpine meadows on the Tibetan Plateau: Problems overlooked and suggestions for change SO AMBIO DT Editorial Material C1 Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. Adm Ctr Chinas Agenda 21, Informat Div, Beijing 100089, Peoples R China. RP Wang, XH (通讯作者)，Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China. EM wangxh@igsnrr.ac.cn TC 37 Z9 44 PD MAY PY 2004 VL 33 IS 3 BP 169 EP 171 UT WOS:000221132300009 DA 2023-03-23 ER PT J AU Dong, SK Long, RJ Hu, ZZ Ding, LM Xu, MY AF Dong, SK Long, RJ Hu, ZZ Ding, LM Xu, MY TI Influence of grazing intensity on performance of perennial grass mixtures in the alpine region of the Tibetan Plateau SO NEW ZEALAND JOURNAL OF AGRICULTURAL RESEARCH DT Article AB Effects of grazing intensity on leaf photosynthetic rate (Pn), specific leaf area (SLA), individual tiller density, sward leaf area index (LAI), harvested herbage DM, and species composition in grass mixtures (Clinelymus nutans + Bromus inermis, Elymus nutans + Bromus inermis + Agropyron cristatum and Elymus nutans + Clinelymus nutans + Bromus inermis + Agropyron cristatum) were studied in the alpine region of the Tibetan Plateau. Four grazing intensities (GI), expressed as feed utilisation rates (UR) by Tibetan lambs were imposed as follows: (1) no grazing; (2) 30% UR as light grazing; (3) 50% UR as medium grazing; and (4) 70% UR as high grazing. Leaf Pn rate and tiller density of grasses increased (P < 0.05), while sward LAI and harvested herbage DM declined (P < 0.05) with the increments of GI, although no effect of GI on SLA was observed. With increasing GI, Elymus nutans and Clinelymus nutans increased but Bromus inermis and Agropyron cristatum decreased in swards, LAI and DM contribution. Whether being grazed or not, Elymus nutans + Clinelymus nutans + Bromus inermis + Agropyron cristatum was the most productive sward among the grass mixtures. Thus, two well-performed grass species (Elymus nutans and Clinelymus nutans) and the most productive mixture of four species should be investigated further as the new feed resources in the alpine grazing system of the Tibetan Plateau. Light grazing intensity of 30% UR was recommended for these grass mixtures when swards, LAI, herbage DM harvested, and species compatibility were taken into account. C1 Beijing Normal Univ, Inst Environm Sci, State Joint Key Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. Chinese Acad Sci, NW Plateau Inst Biol, Xinjing 810001, Peoples R China. Gansu Agr Univ, Grassland Sci Coll, Lanzhou 730070, Peoples R China. RP Dong, SK (通讯作者)，Beijing Normal Univ, Inst Environm Sci, State Joint Key Lab Environm Simulat & Pollut Con, Beijing 100875, Peoples R China. EM DSK@irs.bnu.edu.cn TC 3 Z9 3 PD SEP PY 2003 VL 46 IS 3 BP 175 EP 183 UT WOS:000186252800002 DA 2023-03-23 ER PT J AU Lai, CH Smith, AT AF Lai, CH Smith, AT TI Keystone status of plateau pikas (Ochotona curzoniae): effect of control on biodiversity of native birds SO BIODIVERSITY AND CONSERVATION DT Article AB The plateau pika (Ochotona curzoniae) of the Qinghai-Xizang (Tibetan) plateau, People's Republic of China, has been considered a pest because it putatively competes with native livestock for forage and contributes to rangeland degradation. As a result the plateau pika has been poisoned across vast areas of the high alpine meadows of the plateau. The plateau pika has also been considered a keystone species for biodiversity on the plateau. As one test of the keystone species hypothesis, we investigated the effects of poisoning plateau pikas on avian species richness and abundance. We conducted standardized censuses of birds on a number of sites across the alpine grassland of Qinghai province on which pikas either had or had not been poisoned. Avian species richness and abundance were higher on non-poisoned sites, in particular for species that nest in pika burrows such as Hume's groundpecker (Pseudopodoces humilis) and six species of snowfinch (Montifringilla spp., Pyrgilauda spp.), and species that prey on pikas (upland buzzard, Buteo hemilasius; black-eared kite, Milvus lineatus). The plateau pika thus appears to be both an allogenic engineer and a keystone species. Poisoning pikas reduces biodiversity of native species on the Qinghai-Xizang plateau, therefore management decisions concerning plateau pikas should reflect caution and careful assessment. C1 Arizona State Univ, Dept Biol, Tempe, AZ 85287 USA. RP Smith, AT (通讯作者)，Arizona State Univ, Dept Biol, Box 871501, Tempe, AZ 85287 USA. EM a.smith@asu.edu TC 121 Z9 151 PD SEP PY 2003 VL 12 IS 9 BP 1901 EP 1912 DI 10.1023/A:1024161409110 UT WOS:000183444300008 DA 2023-03-23 ER PT J AU Wang, GH Zhou, GS Yang, LM Li, ZQ AF Wang, GH Zhou, GS Yang, LM Li, ZQ TI Distribution, species diversity and life-form spectra of plant communities along an altitudinal gradient in the northern slopes of Qilianshan Mountains, Gansu, China SO PLANT ECOLOGY DT Article AB We studied the distribution pattern, species diversity and life-form spectra of plant communities along an altitudinal gradient in the mid-section of the northern slopes of Qilianshan Mountains by means of multivariate analyses. Two data sets (167 species x 75 plots, 10 environmental variables x 75 plots), originated from the fieldworks in 1998-1999, were subjected to TWINSPAN and DCCA, resulting in 8 major plant communities: 1) Asterothamnus centraliasiaticus-Halogeton arachnoideus desert grassland on azonal substrates from 1450 to 1600 m and 2) zonal Reaumuria soogorica desert grassland on gravels from 1470 to 1900 m; 3) Stipa przewalskii-Stipa purpurea montane grassland from 2200 to 2900 m; 4) Polygonum viviparum alpine grassland from 2900 to 3700 m; 5) Caragana stenophylla-Ajania fruticulosa dry-warm shrubland from 2350 to 2800 m; 6) Sabina przewalskii mid-wet warm forest from 2700 to 3300 m; 7) Picea crassifolia cold coniferous forest from 2450 to 3200 m; 8) Caragana jubata wet-cold alpine shrubland from 3100 to 3700 m. Species diversity and species richness of both grasslands and forests peaked at the intermediate portion of the elevational gradient. Evenness might be strongly influenced by either biotic or abiotic factors at a local scale, while seems quite independent of an elevational gradient at landscape scales. Beta-diversity decreased from 1500 to 3700 m, indicating that species turnover declined with increased elevation. Both richness of life-form and total species richness in a given altitudinal belt (gamma-diversity) peaked at intermediate elevations, while relative species richness of different life-form varied differently along the altitudinal gradient. C1 Chinese Acad Sci, Inst Bot, Lab Quantitat Vegetat Ecol, Beijing 100093, Peoples R China. RP Wang, GH (通讯作者)，Chinese Acad Sci, Inst Bot, Lab Quantitat Vegetat Ecol, Beijing 100093, Peoples R China. EM ghwangaq@ns.ibcas.ac.cn TC 120 Z9 149 PD APR PY 2003 VL 165 IS 2 BP 169 EP 181 DI 10.1023/A:1022236115186 UT WOS:000180750600003 DA 2023-03-23 ER PT J AU Wang, GX Cheng, GD Shen, YP Qian, J AF Wang, GX Cheng, GD Shen, YP Qian, J TI Influence of land cover changes on the physical and chemical properties of alpine meadow soil SO CHINESE SCIENCE BULLETIN DT Article AB Taking the alpine cold meadow grassland in the southeastern part of the Qinghai-Tibetan Plateau as an example, this research deals with the characteristics of alpine meadow soil property changes, including soil nutrients, soil physical properties and soil moisture content under different land coverage conditions. With the degradation of grassland vegetation and the decline of vegetation coverage, soil compactness reduces, gravel content increases and bulk density increases. The originally dense root-system layer is gradually denuded, making the soil coarse and gravel. The change of the organic matter contents with the vegetation coverage change in the surface soil layer (0-20 cm) has shown an obvious cubic polynomial curve process. The organic matter contents increase rapidly when land coverage is above 60%, contrarily decreases on a large scale when land coverage is below 30%. Between 30%-60% of land coverage the organic matter contents remain stable. The total N and organic matter contents in soil have shown quite similar change regularity. Following this the mathematic equations are derived to describe such change processes. Moisture content in soil changes sharply with the vegetation coverage change. Soil moisture content change with the vegetation coverage change has shown a quadratic parabola process. Results have shown that organic matter content and the total N content of the alpine meadow soil decrease by 14890 kg/hm(2) and 2 5505 kg/hm(2) respectively as the vegetation coverage reduces from 90% to less than 30%. The heavy changes of soil physical and chemical properties with grassland degradation have made the recovery of alpine meadow ecological system impossible. The protection of alpine meadow vegetation is of vital importance to the maintenance of the regional soil environment and the regional ecological system. C1 Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. Lanzhou Univ, Sch Resources & Environm, Lanzhou 730000, Peoples R China. RP Wang, GX (通讯作者)，Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Frozen Soil Engn, Lanzhou 730000, Peoples R China. TC 14 Z9 19 PD JAN PY 2003 VL 48 IS 2 BP 118 EP 124 DI 10.1360/03tb9023 UT WOS:000181243500003 DA 2023-03-23 ER PT J AU Zhang, YQ Welker, JM AF Zhang, YQ Welker, JM TI Tibetan alpine tundra responses to simulated changes in climate: Aboveground biomass and community responses SO ARCTIC AND ALPINE RESEARCH DT Article AB High-elevation ecosystems are predicted to be some of the terrestrial habitats most sensitive to changing climates. The ecological consequences of changes in alpine tundra environmental conditions are still unclear especially for habitats in Asia. In this study we report findings from a field experiment where an alpine tundra grassland on the Tibetan plateau (37 degrees N, 101 degrees E) was exposed to experimental warming, irradiance was lowered, and wind speed reduced to simulate a suite of potential changes in environmental conditions. Our warming treatment increased air temperatures by 5 degrees C on average and soil temperatures were elevated by 3 degrees C at 5 cm depth. Aboveground biomass of grasses responded rapidly to the warmer conditions whereby biomass was 25% greater than that of controls after only 5 wk of experimental warming. This increase was accompanied by a simultaneous decrease in forb biomass, resulting in almost no net change in community biomass after 5 wk. Lower irradiance reduced grass biomass during the same period. Under ambient conditions total aboveground community biomass increased seasonally from 161 g m(-2) in July to a maximum of 351 g m(-2) in September, declining to 285 g m(-2) in October. However, under warmed conditions, peak community biomass was extended into October due in part to continued growth of grasses and the postponement of senescence. Our findings indicate that while alpine grasses respond favorably to altered conditions, others may not. And, while peak community biomass may actually change very little under warmer summers, the duration of peak biomass may be extended having feedback effects on net ecosystem CO2 balances, nutrient cycling, and forage availability. C1 CHINESE ACAD SCI,NW PLATEAU INST,DEPT ECOL,XINING 810001,PEOPLES R CHINA. COLORADO STATE UNIV,NAT RESOURCE ECOL LAB,FT COLLINS,CO 80523. COLORADO STATE UNIV,DEPT RANGELAND ECOSYST SCI,FT COLLINS,CO 80523. TC 54 Z9 77 PD MAY PY 1996 VL 28 IS 2 BP 203 EP 209 DI 10.2307/1551761 UT WOS:A1996UN84300009 DA 2023-03-23 ER PT J AU Schaller, GB Liu, WL AF Schaller, GB Liu, WL TI Distribution, status, and conservation of wild yak Bos grunniens SO BIOLOGICAL CONSERVATION DT Article AB Wild yaks Bos grunniens survive only on the Tibetan Plateau where they have declined greatly in range and numbers during the past century because of excessive hunting. Wildlife surveys on the Plateau between 1984 and 1994 revealed that yaks per sist in several small populations and in one large tract of alpine steppe and alpine desert, mostly above 4500 m in elevation, which extends over about 400,000 km(2) primarily in the Tibet Autonomous Region. The Chang Tang Reserve, 284,000 km(2) in size, covers a substantial part of this area and contains an estimated 7000-7500 yaks, a third of these in two relatively small areas. The number of wild yaks probably totals around 15,000. Meat hunting, encroachment by pastoralists into the last strongholds, and hybridization between domestic and wild yaks are among the dangers confronting the animals. Only lar ge protected tracts of wilderness as in the northern Chang Tang Reserve can provide wild yaks with a future. C1 WILDLIFE CONSERVAT SOC, BRONX, NY 10460 USA. TIBET FOREST BUR, LHASA 850000, TIBET, PEOPLES R CHINA. TC 35 Z9 51 PY 1996 VL 76 IS 1 BP 1 EP 8 UT WOS:A1996UB26300001 DA 2023-03-23 ER EF