Calculation of groundwater use by natural vegetation in the non-irrigated plain areas in Xinjiang

This paper takes the non-irrigated plain areas in Xinjiang as the study area, where the natural vegetation draws water mainly from the shallow groundwater to satisfy its demands. Through interpretation of TM satellite images and hydro-geological investigations, understanding of the unsaturated strata, shallow water depth, distribution and coverage of natural vegetation was obtained. Based on calculation units divided by using GIS techniques and data of shallow water evapo-transpiration from the typical area groundwater balancing experimental stations, parameters of phreatic water evaporation and vegetation conversion parameters were decided and thus the total groundwater use by the natural vegetation in the study area is calculated as 63.7762×10⁸m³/a under current conditions.