Effect of climate and land use change in Ebinur Lake Basin during the past five decades on hydrology and water resources

Abstract

Remote-sensing images of Ebinur Lake Basin including six years (1960, 1972, 1990, 2000, 2005 and 2010) were interpreted through RS and GIS. Land use changes in Ebinur Lake Basin during the past five decades were analyzed according to interpretation results. On this basis, effect of land use changes on hydrology and water resources was analyzed. Results show that the land use pattern in Ebinur Lake Basin changed greatly from 1960 to 2010. Cultivated Land and Urban-Rural Construction Land increased, while other landuse types decreased. Most areas were Unused Land. Generally, oasis expanded continuously, but oasis in Ganjiahu Zone at downstream of the Kuitun River Basin reduced to some extent. Runoff of the Kuitun River and Jinghe River increased gradually, but runoff of the Bortala River reduced continuously. Both inflows and lake area declined year by year. The groundwater level dropped significantly and water deteriorated continuously. Due to the decelerating wind blowing, evaporation in the basin reduced accordingly. Hydrology and water resources changes in Ebinur Lake Basin in past five decades were mainly caused by continuous expansion of Cultivated Land and oasis, continuous population growth and hydraulic engineering constructions. However, oasis expansion shall be limited within the carrying capacity of water resources. To maintain ecological security in the basin, it is necessary to determine reasonable oasis area, optimize river system structure, and improve utilization efficiency of water resources.