Spatiotemporal Distribution And Influencing Factors Of Air Pollutants In Jiangxi Province

With the development of society,heavy industry is now the backbone of every country’s national economy.With a series of environmental problems such as global warming and sea level rise,people are increasingly concerned about the quality of living environment.Jiangxi Province main atmospheric pollutant concentration data analysis mostly stay in the descriptive stage and short period,single pollutant or part of the point analysis,for 6atmospheric pollutants CO,NO₂,O₃,PM_2.5,PM₁₀,SO₂and meteorological factors,social and economic factors of the correlation between the research is relatively less.Therefore,it is of great significance to study the air quality of air pollutants in Jiangxi Province from multiple angles and periods.Based on the air quality monitoring data of 11 prefecture level cities in Jiangxi Province from 2015 to 2018,combined with meteorological factors,socio-economic factors,terrain,land use types and the relationship between days with different pollution levels and wind direction,this paper analyzes the temporal and spatial variation characteristics and influencing factors of pollutants,and then provides direction decision-making basis for the follow-up air pollution control in Jiangxi Province.The conclusions are as follows:（1）From the interannual change point of view,the study period in addition to O₃concentration did not significantly decline,the other 5 items of air pollutants CO,NO₂,PM_2.5,PM₁₀,SO₂are showing a significant downward trend.From the perspective of seasonal variation,the contribution of O₃ seasonal concentration is as follows:summer>spring>winter>autumn,PM_2.5 and PM₁₀ seasonal concentration is as follows:winter>autumn>spring>summer.From the perspective of intra-day variation,the concentration of NO₂ in the daytime was lower than that in the night,and the proportion of the concentration in the night increased year by year.As a whole,O₃ concentration was higher in the daytime than at night and the difference was larger,contrary to the trend of NO₂concentration.The concentration of SO₂ showed a trend from uneven to relative average year by year.From the time characteristics of weekly variation,the pollutant concentrations of CO,PM_2.5,PM₁₀ and SO₂ were significantly higher on Saturday and Sunday than from Monday to Friday,indicating that the concentrations of these four pollutants were significantly higher on weekends,and there was a"weekend effect".（2）From the perspective of spatial distribution characteristics,CO has been improved in all areas except Pingxiang City and Ganzhou City,where the CO concentration is still high.The highest overall NO₂ concentration was found in Nanchang and Jiujiang.Jiujiang City is the only area with relatively high O₃ concentration.PM_2.5 concentration increased year by year,Pingxiang City and Jiujiang City had a high concentration distribution,Jiujiang City,the central,western and southern parts of Jiangxi Province PM_2.5 problem is serious;The annual average PM₁₀ concentration in Jiangxi Province has been increasing year by year.By 2018,only a few areas showed low PM₁₀ concentration,and most areas reached the second-level national standard of PM₁₀.SO₂ in Jiangxi Province developed from medium to poor and then to good.The areas with high concentration were in the eastern part of Jiangxi Province,and the whole province all reached the second-level national SO₂ standard.（3）As time goes on,the spatial agglomeration effects of CO,NO₂ and SO₂ in Jiangxi Province increase year by year,among which NO₂ has the strongest agglomeration effect,while O₃,PM_2.5 and PM₁₀ are not obvious.The center of gravity shifts to the southwest and pollutants gather to the south.（4）In Jiangxi Province,the air pollutants NO₂,PM_2.5 and PM₁₀ have strong positive correlation with the average air pressure,NO₂ and PM₁₀ have strong negative correlation with the average air temperature,O₃ has strong negative correlation with the average air pressure,NO₂ has strong positive correlation with the population density,GDP and total energy consumption,and CO has strong negative correlation with the green space rate of the built-up area.（5）Due to the special topography and land use types in Jiangxi Province,the air pollutants are greatly affected by the northeast,due east and southwest wind.