The Research Of Ecological Water Requirement Of Lake Aiding River

Aydingkol Lake is a typical inland lake in northwest arid and semi-arid regions. In recent years, with the rapid development of social economy, water is increasingly in great demand in industry in the lake Aydingkol basin, and the contradiction between water resources and ecological degradation has become increasingly serious. Currently, the ecological environment in Aydingkol Lake has been seriously destroyed, and the lake has shifted from perennial lake into a seasonal lake. Therefore, the ecological evolution analysis and water requirement calculation of Aydingkol Lake is particularly important.This article first analyzed the ecological hydrological characteristics, current situation of the ecological system and its evolution trend in the study area. According to the ecological function of each component in the ecological system, the article analyzed the composition of the basin’ecological water requirement, calculated the ecological water demand of the years who maintains basic ecological characteristics of the lake. According to the water situation, the satisfaction of ecological water demand is analyzed. Based on this we can get some conclusions as follows:(1) The water area of the the Lake Aydingkol is an "indicator" of the basin’ecological environment. However, the area is shrinking gradually in recent years, especially since 2000. It indicates the ecological environment of Aydingkol Lake is become more and more worse.(2) The area of the natural vegetation is 1236.6 square kilometers now, compared with 1980s the area decrease about 413km2 with a decrease rate of 20.5km2/a. About 64% of the grassland around the lake can’t grow well, and 80% of the forestland was inhibited as well.(3)Analyzed the relationship between the water demand of social and ecosystem and the development history of the economical and get the conclusion of that the goal of the environment protecting is maintaining the basic features of the ecosystem and ensuring the harmony between people and ecosystem. And we define the water demand according to the basic goal as the basic ecological water requirement. By analyzing the ecology function of the ecosystem we conduct that there are three components of the water demand of Aydingkol lake which are evaporation of the river, evapotranspiration of the vegetation and water requirement of the lake.(4) Aydingkol lake is the end of the water cycle in its basin and is a indicator of its ecological condition. It has many ecological functions such as Climate regulation, breaking wind and sand, life supply and so on. However, there is some water surface or not determines it plays a positive effectives or negative function. Based on the analysis of the water area of Aydingkol lake in year 2000-2013 we think year 2000-2005 is an acceptable group of years, which maintain the basic characteristics of the lake. By the analyzing of the natural xeric vegetation and the depth of groundwater we can get the conclusion of about 90% of the natural xeric vegetation around the lake growth well.(5) The basic water demand of Aydingkol lake was calculated and the results show that the ecological water demand is 356 million cubic meters of the natural xeric vegetation around Lake Aydingkol,.The evaporation of the water surface is 67 million cubic meters. Ecological water supplement of Lake Aydingkol is 80 million cubic meters. So, the total is 503 million cubic meters. But the analysis and calculation of water consumption in the lake area shows that the basin’ ecological water demand cannot be satisfied now and the deficit is 0.32 billion. However, in the future ecological water requirement still cannot be satisfied, and the water deficit in year 2020 and 2030 is 0.213 billion and 0.204 billion cubic meters respectively.