Research On Water Quality Prediction And Evaluation Of Urban Artificial Lake

Urban construction of our country have made Progresses by leaps and bounds in recent years, each city is making its own image carefully. Planning and constructing the city water landscape project scientifically can improve the urban ecological environment and human settlements greatly. Using and building the urban water landscape reasonably can have considerable economical benefit as well as social comprehensive benefit. However, in the construction and operation process of city water landscape, massive hazardous substances such as the industrial wastewater,the domestic wastewater,the chemical fertilizers and the agricultural chemicals and so on are dispersed into in the urban artificial lake because of absence of reasonable plan and management, which leaded to the water quality deterioration and the water eutrophication in the city artificial lake.This paper closely combines the urban artificial lake landscape construction and lake water quality improvement technology, analyzes the research situation of water quality prediction and evaluation on urban artificial lake. It linked to the reality of Xi'an Qu-jiang South-Lake construction, in view of our country urban lake water environmental pollution present situation, specially the water quality condition of Xi'an landscape water area, and then forecasted the change rule of water quality in different scenes, carried through fuzzy comprehensive assessment and assessment of lake eutrophication based on its forecast result.The main conclusions obtained from this paper could be summarized as follows: (1) The primary environmental problem of South-Lake is the input of contamination such as N,P,BOD₅,which brings on the water quality deterioration and the water eutrophication (2)Using the scheme of "water diversion by the recession flow of Qu-jiang,water replenishment by the recession flow of Qu-jiang,rainfall collected in the planning area dealed with constructed wetland" could make the water quality be the best, which belongs to Class III in the criterion for surface water quality, and that the assessment of lake eutrophication is in the middle-nutrition level.(3) The water quality of South-Lake has a distinct improvement after the daily water replenishment is disposed by the constructed wetland ecology processing system, which not only protect the entironment, but also enrich the landscape. So the constructed wetland has the efficacy of "ecotypic sewage treatment plant". (4) Reclaimed water from sewage treatment plant can be used as the daily water replenishment for South-Lake, which will be a strategic planning for resolveing the water shortage in Xi'an as well as utilizing the precious sewage resources. But resultingly it could bring on eutrophic water, the reuse of reclaimed water needs more strict treatment.Finally, based on the water quality prediction and evaluation for South-Lake, This paper analyzed the environmental problems may arise in the future and put forward corresponding measures to protect the water quality to improve the urban water ecosystem which making service for the urban ecological construction.