萧山区典型月份大气环境质量现状评价与分析OA

This study investigated the atmospheric environmental quality in Xiaoshan District from November 2023 to April 2024.Three sampling sites in the central,eastern,and southern Xiaoshan regions were selected to measure the mass concentrations of SO2,NO2,CO,O3,PM2.5 and PM10.Temporal variation characteristics of pollutants were analyzed,and evaluations were conducted using the air quality index(AQI)and principal component analysis(PCA).Results revealed that the daily mass concentrations of PM2.5,PM10 and NO2 exhibited bimodal distributions,while O3 showed a single afternoon peak.Monthly O3 concentrations followed a"U-shaped"trend,whereas other pollutants displayed an"inverted U-shaped"pattern during the first four months,with PM2.5 and NO2 slightly increasing in March before declining.AQI evaluation indicated that 85.17％of days met good-to-excellent air quality standards,with PM2.5 and NO2 being the primary pollutants,accounting for 36.3％and 19.8％of the monitored days,respectively.PCA identified three principal components influencing air quality,with the first component accounting for 52.332％of the variance,primarily driven by PM2.5,PM 10 and NO2.Comprehensive analysis showed the worst air quality in January and the best in April.Further findings highlighted meteorological conditions(temperature inversion,wind speed)and social activities(fireworks and firecracker combustion)as key factors affecting air quality in Xiaoshan District.