Research On Digital Watershed Water Quality Management Model Of Tangpu Reservoir

As China's economic development, the deterioration of water pollution, water shortages is exacerbated. Rivers and lakes in our country are polluted widely and 75 percent of the lakes had varying degrees of eutrophication. The main freshwater lakes such as Dianchi Lake, Chaohu Lake, Taihu Lake eutrophication is very seriousl and some waters have lost water body functions.90 percent of urban water pollution is serious, and 60 percent to 70 percent of the total water deficit in southern city is due to water pollution.10 percent of our country's urban groundwater quality is deteriorating. In recent years, research has proved that the discharge od the agricultural non-point source pollutants, is one of the main causes of water pollution, especially eutrophication of water quality, especially in those drinking water reservoirs and lakes. Studies have shown that in areas dominated by agriculture, the nitrogen and phosphorus loss along with soil erosion is 7 times and 10 times as that in forest cover area separately. Therefore, controlling of agricultural non-point source pollution and soil erosion are necessary measures to water quality management of the drinking water source.Tangpu Reservoir is the only one drinking water source of Shaoxing urban area, Shaoxing County and Shangyu City, the scale of water supply being one million ton per day, having an important social status, and the sustainable use of water resources and water quality is referred to the sustainable development of theYushao plains and the health of nearly 3 million people, so water pollution prevention and control is particularly important.In this paper, based on the pollution investigation of Tangpu reservoir basin, the water resources management model meet the case of Tangpu reservoir basin is analysed and chose. The water qaulity management model of Tangpu reservoir based on GIS technology is establish to quantitative study of watershed runoff and non-point source pollution, pollution process and distributing regulation, the main pollution factor, the contribution rate of pollution of every rivers and every towns in the basin as well as the total pollution load of the basin (in which non-point source pollution is the main research content), the initial fitting accuracy reaching 90%. The scientific and quantitative means are used to study the runoff and non-point source pollution of Tangpu reservoir basin, to improve the management level of the reservoir, to improve water quality of Tangpu reservoir, to carry on the eutrophication prevention and cure work of the reservoir water, to achieve the maximum function of the reservoir and to achieve sustainable use of water resources.