The Research Of Dongchang Lake Water Quality Change And Water Environment Management

China is one of the countries in the world which has many lakes, it has about 2 millions more lakes, owning one-tenth of the world natural lakes, with a total area of about 8 million km2, of which more than 1 km2 lakes approximately 2,300. The role of lakes on the ecosystem and human society is very large. For a city, it is urban business card and a city of the best living advertising to a good lake environment. With its unique geographical location and urban economic development role, the urban lakes play a very important role in urban ecological environment.But in recent years, with the acceleration of urbanization, and the city industrial wastewater, sewage and urban sewage treatment plants increasing, adding city landfill leachate treatment and rainwater, agricultural runoff pollution aggravating, adding the urban lakes own special hydrodynamic characteristic and the urban lakes by human destructive larger, and so on, the pollution load of urban lakes embraced are often more than their own self-purification capability, water environmental damage, and the ecological environment is worsening day by day.As a typical northern cities lake, the Dongchang Lake also has the common feature of urban lakes. According to research, its water quality and water clearly influenced by the source - the yellow change.As the fast development of Liaocheng's economic, social, and the tourism, and the city scale unceasingly expanding, and the industrial wastewater and sewage emissions increasesing year by year, the Dongchang Lake and its surrounding water system catch serious pollution, and they are facing serious eutrophication problem.The main pollutants of the Dongchang Lake have reached the following condition in 2009: total nitrogen in quantity V type, total phosphorus IV - V kind, COD forⅢto IV class. Water quality is in medium eutrophication stage. Meanwhile, the DongChang Lake environment management also exists some problems, such as "management department overlapping functions", "exploitations are in disorder", "management not have rules to abide" etc. Therefore, carrying systematic scientific research on The Dongchang Lake is of great significance to the development of Liaocheng social economy, but also beneficial to the coordinate development of liaocheng economy, society and environment, really realize scientific development.Basing on the monitoring data of environmental protection bureau and the lab for the Dongchang Lake, this paper analyzes the change tendency of the lake water quality, which concludes the year and month change tendency of the key pollution indicators of the Dongchang Lake, and analyzes the change trend of the monitoring stations, and compares the monitoring stations pollution. It not only can provide premise and direction for water quality prediction and control work, but also be helpful for lake scientific renovation.Research shows that:1. The year's change tendency of the lake water quality indexes in 2001-2010 is: permanganate index of the annual change trend is rose at first, then decreased; TN first decreases then rose; TP first greatly decreased, then slightly elevated; PH is slightly elevated, but the rangeability is not too much.2.The comparison results of each year's pollution index about monitoring stations in 2001—2010 : the pollution of area C in 2001 is the most serious, region D after; the pollution of the east guan qiao in 2002 is the most serious, and the west guan qiao pollution is the lightest; the pollution of the east guan qiao in 2004 is the most serious; In 2005, the pollution of the north guan qiao is the most serious, and the south is the lightest; The pollution of the west guan qiao in 2006 is the lightest; the pollution of the east guan qiao in 2008 is the most serious.In addition, basing on the present situation of environmental management in DongChang lake , this paper also analyzes the problems in DongChang lake environment management, combining study of lots of references, this paper puts forward the DongChang lake environment management measures, including establish unity of water environment management agencies and perfect DongChang lake environment management system; establish water environment management measures, found public participation mechanism;Make scientific utilization and protection plan; to strengthen the environmental science research of DongChang lake, etc. It can not only provide scientific basis for DongChang lake environment management and planning , but also benefits for the DongChang lake environment of scientific management, at the same time can provide the reference for the local government.