Study On The Design Of Low Impact Measures In Upstream Catchment Area Based On Water Quality Optimization Ability Of Target Water Body

At present,water problem has become a major problem in the process of urbanization in China,and the situation is becoming increasingly severe.Therefore,it is necessary to construct a city water resource management system with many objectives,such as reducing the surface runoff pollution,rationally allocating water resources,optimizing the water quality of the city,reducing the flood disaster in the city,and has positive significance for solving and improving the urban water problems.Based on the control of surface runoff pollution in upstream catchment area,this paper can solve the problem of urban static water pollution more effectively,and explore the coordinated optimization approach and method of urban static water body and upstream catchment water quality under the rain flood management system.This paper summarizes the research on the surface runoff pollution and the static water quality of the city by domestic and foreign scholars,and explores the coordinated optimization management system of water and land water quality in the process of urban hydrology,which provides a feasible way for the urban water environment control in China.The research,through qualitative and quantitative methods,takes the artificial lake of Chengdu people’s Park as an example,analyzes the relationship between the target water environment capacity and the single factor pollution of surface runoff in upstream catchment area,analyzes the layout of low impact development measures under different conditions,and studies the water quality optimization target setting,water land collaborative optimization method and software simulation method.The following research results are obtained:(1)Because of the limitation of the static water body in the city,the capacity of the pollutant is limited.When the total amount of pollutants in the water exceeds its water environment capacity,the water quality standard will be difficult to guarantee.This paper constructs a method of water quality coordination optimization between the target water body and the upstream catchment area.The case study proposes a strategy of improving the runoff quality of the upstream catchment area based on the water quality optimization capability of the target water.On the premise of ensuring the water quality standard of the target water,the relationship between the surface runoff quality change and the pollutant load of the receiving water body is analyzed in depth.By reasonably arranging lid measures The feedback model of water quality optimization design is established to optimize the runoff quality of upstream catchment area,and control runoff quality from the perspective of global.(2)Through the interdisciplinary method research,the estimation method of water environmental capacity of the target water body is obtained,and it is combined with the ecological landscape design.Through the quantitative evaluation method,the maximum load of runoff pollution in the upstream catchment area is determined,and the theoretical basis is provided for the layout design of lid measures in the upstream catchment area,so as to improve the optimization efficiency of runoff quality.(3)Taking the artificial lake in Chengdu people’s Park as an example,this study proposed the layout scheme of lid measures under the goal of water quality optimization of artificial lake.Through the layout of different types of measures and the utilization ratio of measures,the optimal strategy of runoff water quality optimization management was selected,which further verified the feasibility of land water quality collaborative optimization method.