The dynamics of biomass and soil moisture in semiarid land is driven by both the current rainfall and the ecosystem memory.Based on a meta-analysis of existing experiments,an ecosystem model was used to calculate the effect of the rainfall interannual variability on the pattern of biomass and soil moisture in a shrub community.It was found that rainfall interannual variability enabled shrubs to be more competitive than grasses,and to maintain the dominant role over a longer time.The rainfall interannual variability resulted in complex soil moisture dynamics.The soil water recharge in wet years alternated with discharge in drought years.
LIU JunShanXU XiaZHANG Yong,TIAN YuQiang & GAO Qiong State Key Laboratory of Earth Surface Processes and Resource Ecology,College of Resources Science & Technology,Beijing Normal University,Beijing 100875,China