Study on Soil Water Cycle Under Irrigation in Takelamagan Desert

Through successive test of soil moisture by three irrigation methods in takelamagan desert, axiom of soil moisture evaporation and transporation, dynamic of irrigation water cycle, and effect of plant on soil water cycle were studied. The results showed that evaporation intensity and declining rate of soil moisture were greater in sand land than in clay soil land. Dynamic of soil water cycle was rather about irrigation water cycle type than year cycle type in desert hinterland forestation area. The effect of plant on soil moisture cycle process was very significant. The plant transpiration water amount of drip irrigation, ditch irrgation and plot irrigation were 2.73%?1.70%,and1.82%of the soil water respectively, during eight days. The order of transpiration water amount in three sand fixing plant were Tamarix austromongolica nakaiTamarix taklamakanensis Calligonum sp..reversing the order, it was the order of their drought resistant capability.