Study on the effect of ecological water replenishment on the spatial and temporal distribution of water quality in Chaohu Lake based on MIKE21
The two ecological water replenishment routes of the water diversion project from the Yangtze River to Huaihe River were selected,and three ecological replenishment options were designed:option 1 was a double line of Xizhao line and Caichao line introduced into Chaohu Lake,and outflowed through the Chaohu lock of Yuxi River;option 2 was a single line of Zhao River introduced into Chaohu Lake,and outflowed through the Baishitianhe's Baishan Control Junction;option 3 was a single line of ecological water replenishment entered into Chaohu Lake via Zhao River,and outflowed through the Chaohu lock of Yuxi River.MIKE21 software was used to establish a coupled hydrodynamic water quality model of Chaohu Lake to simulate the spatial and temporal changes in the hydrodynamic and water quality processes of Chaohu Lake,as well as the effects of water quality improvement in the four sensitive areas(Nanfei River inlet,Mushan Island,Zhongmiao and drinking water source).In general,it seemed that option 2 had the best effect on improving the water quality of the Nanfei River inlet,Mushan Island and Zhongmiao,while option 3 had the greatest reduction of TP concentration in the drinking water source.Option 2 reduced the potential risk of cyanobacterial outbreaks in the areas of Mushan Island and Zhongmiao,reducing TN/TP from 14.7 and 13.4 to 7.4 and 4.0,respectively.Option 3 reduced the potential risk of cyanobacterial outbreaks in drinking water source from 10.0 to 4.8,reducing the potential risk of cyanobacterial outbreaks in drinking water source.However,the TN/TP of the Nanfei River inlet ranged from 15 to 20 under the three ecological water replenishment options,which indicated that the risk of cyanobacterial outbreaks was still high.The water transfer to Chaohu Lake had a positive effect on the improvement of its water environment and could ensure the safety of the water quality of the drinking water source of Chaohu City,but the potential risk of cyanobacterial outbreaks was still high because the hydrodynamic environment of western half of Chao Lake had not been improved.Therefore,it was necessary to optimize the ecological water replenishment option to effectively control the surface runoff pollution,agricultural surface pollution and overflow pollution of the urban merging system of the river basins entering the lake.
MIKE21ecological water replenishmenthydrodynamicswater qualitycoupled model
万方数据
维普
