Changes of Water Environment at the Lower Reaches of the Tarim River Basin in Recent 50 Years and Its Mechanism

Combined with field trips and hydrological,meteorological and social statistics of the Tarim River Basin in recent 50 years,the mathematical statistics and charts were used to analyze water environment change at the lower reaches of the Tarim River and causes.The results showed that since the 1950s,water source amount reduced,and groundwater depth and groundwater salinity increased;Weilu lake dried up and was in an exhaustion state.The main reasons for the change on the one hand were warm and dry climate trend,less precipitation,large evaporation,high speed of river water reducing;on the other hand,they were human activities,for example,population at the upper and middle reaches increased rapidly,arable land expanded,the distribution and consumption of water resources were uneven.Therefore,more attention should be paid to the influence of human activity in terms of the water utilization and overall control in the Tarim River Basin.