Analysis Of Urban Artificial Landscaping Water Body Purification Efficiency And Water Quality Simulation

With the continuous improvement of the level of urbanization in our country,and the increasing demand of people for good living,the number and status of urban artificial landscape waters with leisure,landscape,and tourism as the main functions are gradually increasing,but the situation of water bodies is not optimistic.Therefore,it is significant to study the purification efficiency of urban eutrophication control technology and water quality simulation.In this paper,taking the water system of the central district of the Beijing Olympic Park as an example,through the collection,monitoring,collation and analysis of water quality data,in accordance with the water quality objectives of the water system to achieve ClassⅢwater quality in Environmental quality standards for surface water,the current status of water environmental quality in the water system is evaluated.Using WASP7.3,the water quality simulation analysis of the water system was conducted in order to provide a basis for the further improvement of water quality in the central district,and provide references for the engineering design of similar water bodies.By monitoring the water quality of the central district water system,except for NH₃-N which meets ClassⅢwater standard,all other pollution indicators have exceeded the standards,TN exceeds seriously,whose compliance rate is only 12.96%during the monitoring period.Using the single water quality parameter evaluation method,the pollution index of TN was as high as 13.32.Combined with the survey and assessment of water pollution sources,reclaimed water is the main source of pollution in the water system,whose pollutant input accounts for more than 83%of the total exogenous pollution.However,only TN concentrations of the four indicators of reclaimed water were much higher than ClassⅢwater standard,which became the biggest burden for water purification.Through the analysis and study of the water purification efficiency in the central district,the purification rate of the pollution indicators from high to low in the water ecosystem is as follows:TN>TP>NH₃-N>COD_Cr.Combined with the evaluation of pollution sources,the TN has the largest purification space among the four indicators,and the remaining three indicators have lower influent water concentration,which results in a greater disturbance of the purification efficiency due to external factors,therefore,the purification effect is not as ideal as TN.Through the experimental research on the water purification efficiency of aquatic plants in the study area,submerged plants played an important role in water purification.In summer,whose purification efficiency of TN and NH₃-N was basically the same as that of the central district water system.In winter,light becomes the main limiting factor for the purification of submerged plants,when the water temperature is low.In order to facilitate in-depth analysis of water quality changes and trends in the central district water system,this paper applies WASP7.3 to simulate water quality,rationally simplifies the water system,selects appropriate parameters and conducts calibration,and obtains a feasible water quality model.The maximum coefficient of variation of the TN simulation results was 0.31,the average absolute error was0.67mg/L,the average relative error was 27.6%;the maximum coefficient of variation of the TP simulation results was 0.37,the average absolute error was 0.009mg/L,the average relative error was 31.2%.