Evaluation Of Air Quality And Analysis Of Spatial And Temporal Distribution Of Pollutants In Hedong District Of Tianji

With the development of modern society,economy and industrialization,air pollution in China is becoming more and more serious.People pay more and more attention to the atmospheric environment industry,so it is very important to evaluate the air quality and analyze the pollution sources.At present,the current situation of air pollution in Hedong District is unclear,the source of pollutants is unclear,and the spatial and temporal changes and distribution characteristics of pollutants are not clear,so it is difficult to find targeted measures in air pollution control.In order to find out these problems,this paper comprehensively analyzes the air pollution status,main sources of pollutants and the characteristics of air pollutants change in Hedong District of Tianjin from the aspects of air quality assessment,emission list of pollution sources and air pollutants change,explores the weak links in the air pollution control in Hedong District,and provides the basis for the next air pollution control work.（1）Through the fuzzy comprehensive evaluation method,it is concluded that the air quality grade of Hedong District in 2015-2017 is grade III,while that in 2018 and2019 is grade II;and the evaluation results of improved grey clustering evaluation method show that the air quality grade of Hedong District from 2015 to 2019 is grade III.Combined with the change of air quality from 2015 to 2019,the evaluation result of fuzzy comprehensive evaluation method should be closer to the actual situation of Hedong District.（2）Based on the list method of pollution source emission,this paper analyzes the emission of eight common pollution sources in 2016,including fixed combustion source,process source,dust source,road mobile source,non road mobile source,solvent use source,storage and transportation source,catering source,and preliminarily finds out the main pollution of six main air pollutants,such as PM_2.5,PM₁₀,SO₂,CO,NO₂,VOCs Source.（3）On the time scale,PM_2.5and PM₁₀are always in high concentration,but the annual average concentration shows a downward trend,and the rate of exceeding the standard decreases obviously.The annual average concentration of O₃is higher and higher year by year.The annual average concentrations of SO₂,CO and NO₂have been low.The average monthly concentrations of the six main pollutants showed a U-shaped curve of low concentration in the middle and high schools of the two ends.However,the concentration change of O₃is just the opposite,showing a"∩"type.The monthly variation of SO₂concentration is not obvious.（4）On the spatial scale,this paper analyzes the spatial concentration distribution of PM_2.5and PM₁₀in 12 streets of Hedong District by the method of geographic information statistics.The results show that the pollution is mainly concentrated in Shanghang road street and Dongxin Street of Hedong District.Through the air quality evaluation,pollution source analysis and pollutant characteristics analysis,the air environment of Hedong District has improved in recent years,which has some effect on the treatment of air pollutants.However,the over standard of PM_2.5,PM₁₀and O₃mainly affects the air quality of Hedong District,which should be focused on.We should combine pollution sources,strengthen air environment control measures and capabilities,and fight a blue sky defense war.