Progress in Study on Response of Arid Zones to Precipitation Change

The pattern of precipitation,including precipitation amount,frequency and intensity,may change in the future according to the prediction of climate change.In arid zones,the soil dynamics, plant growth and vegetation change,desertification and hydrology might be affected by precipitation change.In general,the precipitation in extreme arid zone and arid zone showed an increase tendency whereas the precipitation in some area in semi-arid zone and sub-humid arid zone showed a decrease tendency.The increase of precipitation could enhance the growth of biological soil crust,improve soil water status,promote plant growth,increase vegetation coverage,facilitate the change from desert vegetation to grassland vegetation,and it is benefit to the reversion of land desertification.In addition,the increase of precipitation could also increase the river runoff,lake storage and promote the occurrence of flood,while the decrease of precipitation has the adverse effect.These studies will benefit the prediction of the possible response of ecosystem processes to the potential change of precipitation pattern in arid zones in the future,and it is important to the conservation of natural vegetation and the control of desertification.More field experiments and studies should be conducted in the future,including the effect of increased precipitation or temperature,nitrogen deposition and CO₂ on soil,vegetation,desertification and hydrology of arid zones,so as the more persuasive results could be obtained from these experiments and studies.