Research On Water Quality Appraisal And Water Environmental Capacity In Wenyu River

Wenyu river is the only river which rises in Beijing five water systems and has water all the year.The local economy is influenced because of pollution of water.As the strategy reserve water source,the recover of water quality and full use of water resource of Wenyu river play an important role in 2008 Olympic game and economy promotion and relief to water shortage.Water environmental capacity is the maxmium volume of pollution to meet the needs of water environment quality.It is the basic theory for simulating the water quality and mapping out the prevention and control planning.Water environmental capacity is the focus of research at home and abroad.The article does a research on water environmental capacity in Wenyu river.Through countryside investigation and monitor and improved TOPSIS,the article analyzes water quality and finds the reason of water pollution and then gives several effective management measures.The research results show:(1) Nansha river and Beisha river are serious pollution area,their main pollution factors are COD_Cr.NH₃-N,TP,TN,main stream in upper reaches of the Wenyu river is middle class pollution area,main pollution factors are COD_Cr.NH₃-N.(2) Through objective water environment quality appraisal by using improved TOPSIS,It gives objective water quality level of eight monitoring points on Wenyu River body.:C_V＞C_尚＞C_马＞C_沙＞C_鲁＞C_坝＞C_辛＞C_苇＞C_小.(3) The article selects CODcr and NH₃-N to analyse water environmental capacity.the results show that except Dongsha river,other rivers exceed seriously the water environment capacity.(4) The reasons of pollution are increasing of waste water discharge,lack of waste water treatment facilities,weakness of river self-purification.Based on the reason of pollution and analysis,the article proposes ecology recovery and industry adjustment to improve water quality.The research results provide scientific consultation for improvment of water quality in Wenyu river.