Study And Simulation On A Shallow Lake Based On Two-Dimensional Hydrodynamic And Water Quality Model

Lake eutrophication has become a worldwide problem of environmental governance.As a typical large urban shallow lake in China,the East Lake has been polluted due to a large amount of disorderly pollutant,which leads to the deterioration of water quality and the eutrophication is very serious.How to improve the water quality of the shallow lakes like the East Lake is a major scientific problem urgently needed to be solved in our country's water environment research.In order to control the water pollution problem of the Large East Lake water system,we try to improve the hydrodynamic water quality condition and improve the self-purification ability of the lake by means of the inflow of the Yangtse river and the connecting of the lakes.The water environment is further improved by reducing the pollution source at the same time.Aiming at the characteristics of Large East Lake water system,it is of great theoretical and practical significance for water environment control and water resources management in China to develop a two-dimensional hydrodynamic water quality coupling model to simulate the different diversion schemes and pollution source control schemes,and synthesize the integrated technology of water environment control,diversion dispatching and pollution source controlling.This paper takes the Large East Lake ecological water network project as the background,takes the East Lake and the Shahu lake as the connecting whole,uses the MIKE21 FM software to establish the hydrodynamic model,and compiles the MIKE ECO Lab water quality module by the East Lake's water quality condition,and constructs the two-dimensional hydrodynamic water quality coupling model,The actual situation of East Lake hydrodynamic water quality is numerically simulated,and the parameters of the model are determined and validated by comparing with the measured data.On this basis,this paper combines the Big East Lake ecological water network project,3 kinds of diversion schemes are set up,3 kinds of water transfer schemes and 3 pollution source reduction schemes are combined to obtain 9 kinds of joint dispatching schemes,and the two-dimension hydrodynamic water quality coupling model is used to simulate and analyze,which provides some reference for the joint dispatch of ecological water network of the East Lake.Through the planning of East Lake Ecological Water Network,a comprehensive evaluation index system of water quality index,hydrodynamic water quality Index and economic index was constructed,and finally the simulation result was evaluated comprehensively by the main analysis method and the fuzzy comprehensive evaluation method.The analysis shows that different water diversion schemes have a great difference in the quality of different lakes,and the first diversion scheme is the best one.