Off The Middle Of The Weihe River Pollution Temporal And Spatial Dynamics And Total Control Study

With the rapid development of economy and fast growth of population of Shaanxi Province, as well as the rise of urbanization and industries, the whole province is facing serious environmental situation, and the water pollution problems of Weihe River basin is becoming increasingly prominent. There is water shortage and water supply and demand contradiction in Weihe River in the past 30 years; plenty of industrial waste water and urban sewage is poured into Weihe River so that the quality of water is polluted in varying degrees, affecting the living environment of the coastal people, which is becoming one of the main factors restricting the economic development of Shaanxi. Based on the investigation and assessment of water pollution in the Weihe River, this essay explores the process of spatial and temporal variation of Weihe River's pollution, and then analyses the relationship between Weihe River and its runoff, which provides a preference for controlling water pollution of Weihe River by different time and areas based on the environmental capacity, and achieving the overall compliance of pollution control in the whole river.The main contents are as follows:Firstly comes the investigation and assessment of pollution of Weihe River's current water quality. Monitoring statistics shows that there was no obvious change in the quality of Weihe River during the period of the 10th five-year. Pollution in the 2002 reached peak, and after that shows a declining trend. Weihe River's pollution is organic basically, and the main pollution factors are permanganate index, ammonia nitrogen, BOD and so on. Weihe River's pollution is affected obviously by the temporal and spatial variation, as well as the runoff.Secondly, there are calculations of the water environment capacity and their results analysis. It calculates the water environmental capacity E through the relevant parameters of organic matter's degradation which is simulated by the water quality model; the results show that ammonia and COD of Weihe River are beyond the allowed amounts of pollutant, whose causes are mainly as follows:the achievement ratio of waste water from the polluting industries is low, and pollution load is heavy, coupled with the low rate of urban sewage treatment; the water resources in northwest of China is in shortage, the annual river water changes greatly, and the river lacks adequate ecological water; additionally, rivers near the city lacks broad and comprehensive solid waste, as well as the garbage collection and disposal system.Thirdly are the policies and approaches for Weihe River's water pollution. According to the calculation results of Weihe River's environment capacity, there are recommended policies and approaches for water pollution controlled. Such as establishing clear water rights system, strengthening the construction for the management systems of water pollution control; clearing the main bodies of the sewage treatment, strengthening the sewage charge and the financial management of environmental protection; constituting emission permits and the trading systems, emphasizing the total control of emission permits; accelerating public participation process, and achieving national pollution treatment and so on.