Simulation And Law Research On Pollutant Migration And Transformation In Southern Small Watershed

For small watersheds,they often play an important role in the allocation of urban water resources.With the rapid development of social economy and the continuous improvement of environmental protection awareness in all sectors of society,the characteristics of water environmental pollution in small watersheds are studied,and the impact of water environmental problems on the region is revealed.The impact of sustainable development has certain practical significance.In recent years,increasingly aggravated environmental issues have become a hot issue in the water conservancy industry.How to carry out digital display and information management are currently prominent issues.The information management of water resources in domestic river basins started late,mainly focusing on the monitoring,collection and display of traditional hydrological data,and relatively few applications such as model modeling,data analysis,and intelligent decision-making.This article is based on the Shenzhen Wutong Mountain River Smart Watershed Management and Control System,taking Shenzhen Wutong Mountain River as the research object,modeling and analyzing the water environment problems of its watershed,and deeply understanding the law of pollutant migration and diffusion.With the continuous development of social economy and the continuous progress of information technology,traditional industries are facing the impact and challenge of adapting to the information environment.In response to the above situation,on the basis of consulting a large number of domestic and foreign documents,this project uses MIKE software to simulate the physical and biochemical processes of the hydrology,water volume and various water quality biochemical indicators in the Wutongshan River Basin.In order to explore the changing laws of pollutants in the Wutongshan River Basin,it provides technical and data feasibility references for the Shenzhen Wutongshan River Smart Watershed Management and Control System.The research results of the thesis are as follows:(1)Under hydrodynamic conditions,through repeated calibration of parameter values,the simulated value is roughly consistent with the measured value process line.The root mean square error RMSE of the regular flow rate is 0.14,and the root mean square error RMSE of the verification period is 0.15,which means that compared with the regular data rate,the dispersion of the simulated value and the measured value in the verification period is slightly larger.The efficiency coefficient of the regular model is 0.94,the water balance coefficient is 0.90,and the correlation coefficient is 0.97;the model efficiency coefficient during the verification period is 0.83,the water balance coefficient is 0.87,and the correlation coefficient is 0.94,which proves that the model simulates the Wutongshan watershed well.Runoff process.(2)According to the simulation results of simulated and measured values of ammonia nitrogen and total phosphorus,the model efficiency coefficients Ens of regular ammonia nitrogen and total phosphorus in 2018 are 0.90 and 0.83,respectively,and the correlation coefficients r are 0.90 and 0.89,respectively;verification period in 2019 The model efficiency coefficients Ens are 0.81 and 0.80,respectively,and the correlation coefficients r are 0.95 and 0.91,respectively.The maximum error of the model rate of the regular Wutongshan River section ammonia nitrogen is-35.22%,the minimum error is-0.24%,and the average error is 10.23%;the maximum error of total phosphorus is 23.19%,the minimum error is-3.07%,and the average error is 12.09%.During the model validation period,the maximum error of ammonia nitrogen at the Wutongshan River section in the reservoir was-32.76%,the minimum error was 0.94%,and the average error was 17.34%;the maximum error of total phosphorus was-35.31%,the minimum error was-0.63%,and the average error was 17.13%.(3)According to the analysis of the grid output,the pollutants in the saturation zone of the Wutongshan River Basin are mainly distributed in the middle and lower reaches of the river channel,with small changes along the way.The downstream concentration changes sharply at the beginning of the model simulation,and then gradually becomes 0.There is no change in the upstream area.The pollutants in the slope flow are mainly distributed in the upstream area of the river channel,with small changes along the way.The concentration in the downstream area of the river channel changes drastically at the beginning of the simulation,and then gradually becomes 0.The upstream area has been changing drastically during the simulation process.