Water Resources and Construction Strategy of Ecological Environment in the South Edge of the Tarim Basin
GAO Qian zhao (Cold and Arid Regions Environmental and Engineering Research Institute, CAS, Lanzhou Gansu 730000, China)
There are 43 inland rivers, originated from the Tibetan Plateau, in the south edge areas of the Tarim Basin, within the Hotan and Bayingolin Prefectures, where more than 100 patches of oasis form along the south periphery of the Taklimakan Desert. Climate within the basin is an extremely arid one in the warm-temperate zone. The total water resources in the studied areas are 96.4 ×10 8 m 3, among them 91.4×10 8 m 3 is surface runoff resources mainly from glacier meltwater and precipitation in mountain areas, and only 5×10 8 m 3 is non-repeat groundwater resources. These limited water resources are important natural resources not only for regional economic development, but also for maintaining ecological balance in the south Tarim Basin. Mountains coexist with plains, oases coexist with sandy desert areas, and agriculture areas coexist with animal husbandry areas. Thus transition belts form in the south periphery of the Taklimakan Desert, which are typical vulnerable ecological environment zones. Water resources systems are closely related with ecological environment factors through hydrological cycle in an organic whole. In order to achieve sustainable development and good circulation of ecological environment, physical environment and resources development, climatic and hydrological characteristics, surface and ground waters in the plains in front of mountains and groundwater in the Taklimakan Desert are discussed systematically in this paper. So do the ecological environmental vulnerability and human activity impact, and the observed processes and expected trends of land degradation in the South Tarim Basin. Since 1900, especially since 1950, human activities have deeply impacted on the ecological environment of oases through development and use of water, and this degradation is accelerating. Therefore the opportunity of West China Development must be grasped. Water resources utilization will be adjusted and allocated optimistically, considering ecological environment improvement and reconstruction with technology progress and ecological planning. Four measures of ecological construction strategy against desertification are put forwards so that to control the land degradation and to run into a soundly circulation step by step. They are controlling the balance between irrigation water and ecologically demand water, transforming the traditional developing model of being agriculture first before, determining and guaranteeing water supply for ecological demand in degraded oases by rational planning, and protecting available vegetation from destruction and promoting ecological environment in developing mineral resources.