1) Prof. Xinping Wang

A major concern for the sustainability of revegetated desert ecosystems is accounting for the soil moisture dynamics which is influenced by the revegetated shrub patches. Most field observations indicate that soil moisture at shrub patches level varies with the stochastically occurrence of rainfall events. Based on a study of the long-term field observation on the revegetated desert ecosystem, we find that the soil moisture correlates closely to the densed root zone of shrub patches, and it can be quantified by analytical description of the stationary and transient joint behavior of shrub patches evapotranspiration and precipitation. The experimental results indicate that the size and diversity of plant species in water-limited ecosystems can be determined by soil moisture, which is a comprehensive indicator for shrub water resource competition. These results suggest that revegetating large sandy areas with desert shrubs could reduce soil water storage by transpiration, which could significantly change groundwater recharge conditions. Revegetation has to be balanced with recharge/groundwater needs of local populations. However, from a viewpoint of desert ecosystem stability, it appears that natural rainfall can sustain desert shrubs, thereby reducing wind erosion on the surface of sand dunes.