The Improved Model Research Of Water Environment Capacity Of Nenjiang River Based On MIKE11

Water resources not only play an important role in the ecological environment,but also the stability development of human economic and social can not be without water resources.But in recent decades with the rapid development of productivity and urbanization speeding up,the use of water is increasing and water environmental problems caused by human activities significantly,restricting China's economic and social sustainable development.In view of the present situation and problems of Nenjiang River pollution,this topic development the key technologies of water environment capacity optimization research,river water pollution control and management,achieve regional water quality safety and water ecological security and provide technical support for the comprehensive management of water environment.This paper evaluates the Nenjiang River water quality situation according to the investigation of point source pollution and non-point source pollution,according to the evaluation results,the Nenjiang River and Songhua River near the Sancha River are selected for further model building.Then collect the study reach river data information and establish network file,section file,etc.This information is integrated into the simulation file to build the water dynamic model.Then set the AD parameter file and water quality boundary conditions based on water dynamic model.Finally,Hydrodynamic-water quality coupling model was constructed.This paper establish the optimization model of water environmental capacity based on MIKE11 through the comprehensive analysis of unfavorable factors in the calculation of water environment capacity,introducing the rate of water quality reaching standard and inhomogeneous coefficient of mixing process.By model simulation and algorithm calculation,this paper obtain that:(1)In line with the hydrodynamic conditions of the roughness value,Nenjiang is 0.026,second Songhua River is 0.021,the degradation coefficient of COD in the water quality model is 0.08-0.12/d,NH3-N is 0.06-0.10/d;(2)The water environmental capacity of COD calculated by optimization method is 18209.5 t/a,accounting for 78% of the computational results 23154.35 t/a of the traditional algorithm,NH3-N calculated by optimization method is 678.96 t/a,accounting for 69% of the traditional algorithm 978.79 t/a,also,there are some differences in water environmental capacity in different water periods.The result of optimization method is more in line with the actual situation,higher security,and can provide technical support for water resources management and pollution control,which is conducive to the coordinated development of regional social economy and water resources protection.