How precipitation and grazing influence the ecological functions of drought-prone grasslands on the northern slopes of the Tianshan Mountains, China?

作     者：HUANG Xiaotao LUO Geping CHEN Chunbo PENG Jian ZHANG Chujie ZHOU Huakun YAO Buqing MA Zhen XI Xiaoyan HUANG Xiaotao;LUO Geping;CHEN Chunbo;PENG Jian;ZHANG Chujie;ZHOU Huakun;YAO Buqing;MA Zhen;XI Xiaoyan

作者机构：Qinghai Provincial Key Laboratory of Restoration Ecology for Cold RegionsNorthwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Key Laboratory of Adaptation and Evolution of Plateau BiotaChinese Academy of SciencesXining 810008China State Key Laboratory of Desert and Oasis EcologyXinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of SciencesBeijing 100049China Xinjiang Grassland Technical Popularization StationUrumqi 830049China Qinghai Environmental Sciences Research and Design Institute Co.Ltd.Xining 810007China 

出 版 物：《Journal of Arid Land》 (干旱区科学（英文版）)

年 卷 期：2021年第13卷第1期

页      面：88-97页

核心收录：

学科分类：0710[理学-生物学] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 0709[理学-地质学] 09[农学] 0708[理学-地球物理学] 0903[农学-农业资源与环境] 0815[工学-水利工程] 0705[理学-地理学] 

基　　金：This research was funded by the Chinese Academy of Science(CAS)“Light of West China”Program(2018 Title:“The effect of grazing on grassland productivity in the basin of Qinghai Lake”) the Key R&D and Transformation Projects in Qinghai Province of China(2018-SF-146) the Province Natural Foundation of Qinghai(2017-S-1-04,2020-ZJ-925) the Xinjiang Uygur Autonomous Region Grassland Ecological Restoration and Subsidy Monitoring Support Project(XJCYZZ202001) the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0302). 

主　　题：climate change human activity aboveground biomass precipitation use efficiency soil volumetric water content water stress 

摘      要：Drought-prone grasslands provide a critical resource for the millions of people who are dependent on livestock for food security.However,this ecosystem is potentially vulnerable to climate change(e.g.,precipitation)and human activity(e.g.,grazing).Despite this,the influences of precipitation and grazing on ecological functions of drought-prone grasslands in the Tianshan Mountains remain relatively unexplored.Therefore,we conducted a systematic field investigation and a clipping experiment(simulating different intensities of grazing)in a drought-prone grassland on the northern slopes of the Tianshan Mountains in China to examine the influences of precipitation and grazing on aboveground biomass(AGB),soil volumetric water content(SVWC),and precipitation use efficiency(PUE)during the period of 2014–2017.We obtained the meteorological and SVWC data using an HL20 Bowen ratio system and a PR2 soil profile hydrometer,respectively.We found that AGB was clearly affected by both the amount and seasonal pattern of precipitation,and that PUE may be relatively low in years with either low or excessive precipitation.The PUE values were generally higher in the rapid growing season(April–July)than in the entire growing season(April–October).Overall,moderate grazing can promote plant growth under water stress conditions.The SVWC value was higher in the clipped plots than in the unclipped plots in the rapid growing season(April–July),but it was lower in the clipped plots than in the unclipped plots in the slow growing season(August–October).Our findings can enhance the understanding of the ecological effects of precipitation and grazing in drought-prone grasslands and provide data that will support the effective local grassland management.