Cascade water system composed of Hongyan Reservoir and Panxi River is located in the main urban area of Chongqing.The phenomenon of water eutrophication of this water system is serious.Presently,there are many water environment protection technology researches on single water body,but researches on water system composed of rivers and lakes are relatively inadequate,and the mutual coordination of comprehensive improvement of water environment is also not enough.Based on the water environmental status and the...