Evapotranspiration and soil water relationships in a range of disturbed and undisturbed ecosystems in the semi-arid Inner Mongolia,China

作     者：Nan Lu Shiping Chen Burkhard Wilske Ge Sun Jiquan Chen 

作者机构：Department of Environmental SciencesUniversity of ToledoToledoOH 43606USA Research Center for Eco-Environmental SciencesChinese Academy of Sciences18 Shuangqing RoadBeijing 100085China State Key Laboratory of Vegetation and Environmental ChangeInstitute of BotanyThe Chinese Academy of Sciences20 Xiangshan NanxincunBeijing 100093China USDA Forest Service Southern Research Station920 Main CampusVenture II BuildingSuite 300RaleighNC 27606USA 

出 版 物：《Journal of Plant Ecology》 (植物生态学报（英文版）)

年 卷 期：2011年第4卷第1期

页      面：49-60页

核心收录：

学科分类：09[农学] 0903[农学-农业资源与环境] 090301[农学-土壤学] 

基　　金：Natural Science Foundation of China(30928002) National Aeronautics and Space Administration(NASA)-NEWS Program of US(NN-H-04-Z-YS-005-N) the Outstanding Overseas Scientists Team Project of CAS the State Key Basic Research Development Program of China(2007CB106800) the National Basic Research Program of China(973 Program)(2010CB833501) 

主　　题：evapotranspiration soil water storage land use Inner Mongolia semi-arid region eddy-flux measurements 

摘      要：Aims Evapotranspiration(ET)is a key component of water balance and is closely linked to ecosystem *** arid regions,large proportion of precipitation(PPT)is returned to the atmosphere through ET,with only a small amount available to *** objective was to examine the variability in ET–soil water relationship based on a set of ecosystems that are representative for semi-arid Inner Mongolia and its main land use *** This study used Eddy covariance(EC)data of water vapor(***,mm),PPT(mm),soil volumetric water content(VWC,%),root biomass density and soil properties from three paired sites in semi-arid Inner Mongolia:cropland(Cropland-D)versus undisturbed grassland(Steppe-D),grazed grassland(Grazed Steppe-X)versus fenced grassland(Fenced Steppe-X)and poplar plantation(Poplar-K)versus undisturbed shrubland(Shrubland-K).The paired sites experienced similar climate conditions and were equipped with the same monitoring *** Findings The ET/PPT ratio was significantly lower at Cropland-D and Grazed Steppe-X in comparison to the undisturbed grasslands,Steppe-D and Fenced *** differences are in part explained by the lower VWC in the upper soil layers associated with compaction of surface soil in heavily grazed and fallow *** contrast,the ET/PPT ratio was much higher at the poplar plantation compared to the undisturbed shrubland because poplar roots tap *** VWC of different soil layers responded differently to rainfall events across the six study *** for Poplar-K,ETwas significantly constrained by VWC at the other five sites,although the correlation coefficients varied among soil *** relative contribution of soil water to ET correlated with the density of root biomass in the soil(R2=0.67,P0.01).The soil water storage in the upper 50 cm of soil contributed 59,43,64 and 23%of total water loss as ET at Steppe-D,Cropland-D,Shrubland-K and Poplar-K,*** across-site analysis indicate