Research On Water Quality Assessment And Prediction Of Yuqing Lake Reservoir

In recent years,along with China's rapid socio-economic development and continuing population growth, large quantities of untreated industrial wastewater and domestic sewage have been discharged directly into rivers, lakes and seas which leads to increasingly serious water pollution and decreased water quality. The increasing pollution of the water environment has been seriously constraining China's socio-economic development, endangering the ecological environment and affecting the people's lives and health.Jinan City in Shandong Province as the political, economic and cultural center is the town of water shortage.Surface water makes up an important proportion of the city's water for production and daily life. Yuqing Lake Reservoir with storage area of 4.90 square kilometers is a large water supply reservoir to Jinan City which is located in the junction of Huaiyin District and Changqing District of Jinan City. Yuqing Lake Reservoir is one of three water source passengers in Jinan City,its water quality of the pros and cons has an important impact on the water supply for Jinan City. This paper which relied on study on Yuqing Lake Reservoir, on the basis of reading large number literature about water quality assessment and prediction both foreign and internal and by quantitative study on water quality assessment and prediction of Yuqing Lake Reservoir provided an important scientific basis for water environmental management and planning of Yuqing Lake Reservoir.This paper selected seven indicators of the quality factors to assess and predict water quality based on the monitoring date for Yuqing Lake Reservoir by the actual situation. In the choice of assessing methods,the method of non-state high-dimensional data which is based on the emerging data-driven statistical method --projection pursuit method was applied and made the effect of the higher resolution. On the basis of the application of water quality assessment based on projection pursuit, considering water environment assessment system with multiple objectives and the characteristic of fuzzy, this paper gave value of the ratings of Yuqing Lake Reservoir in five years from 2003 to 2007 by projection pursuit method coupled with the fuzzy recognition theory, with projection pursuit method determining seven assessment indicators' weights. The results of the study showed that water quality rates of Yuqing Lke Reservoir are III Class from 2003 to 2007, the main pollutants were organic pollutants, the most serious pollution period was in 2006 and a trend of pollution were increasing from 2006 to 2007.On the water quality prediction of Yuqing Lake Reservoir, the paper seleted CODc, ammonia nitrogen, total phosphorus, total nitrogen which were relatively serious pollution for study. As a result of the short time series and serious lake of monitoring date, this paper used grey system theory to establish one-dimensional time series predictionmodel--GM (1,1) model to predict CODc, ammonia nitrogen, total phosphorus, totalnitrogen. After validating model accuracy and qualification, the paper predicted concentration of CODc, ammonia nitrogen, total phosphorus, total nitrogen in the next three years and had a certain effectual value.On the basis of water quality assessment and prediction of Yuqing Lake Reservoir, this paper also analyzed water quality trends in interannual variability of Yuqing Lake Reservoir, designed water quality assessment system for real-time assessment of Yuqing Lake Reservoir, and put forward water pollution control measures and proposals for characteristics of the water pollution of Yuqing Lake Reservoir.