新冠病毒肺炎防疫期间济南市空气质量特征分析

Characteristics of air quality during the COVID-19 pandemic in Jinan

为研究济南市新冠病毒肺炎防疫期间空气质量变化特征及其影响因素,分析了2020年1月1日至3月15日济南市空气质量、特征雷达图、PM 2.5组分及气象数据。结果表明:较正常生产阶段,疫情防控期间济南市环境空气质量明显改善,除O 3外各项污染物浓度均下降,受社会经济活动强度下降、车流量大幅减少等人为源影响较大;特征雷达图分析表明,研究时段内济南市大气污染特征未发生明显变化,大气污染受二次颗粒物生成、机动车、扬尘、燃煤等多重因素影响;PM 2.5中水溶性离子浓度居前3位的是NO^(-)_(3)、SO^(2-)_(4)和NH+4,主要由二次生成而来,NO^(-)_(3)和SO^(2-)_(4)质量浓度比为1.22~1.80,受移动源影响突出;研究时段内相对湿度与PM 2.5变化趋势总体一致,表明高湿环境加速污染物二次转化。

In order to assess the characteristics and influencing factors of atmospheric environment during the COVID-19 epidemic in Jinan,the air quality,characteristic radar chart,PM 2.5 components and meteorological factors were studied during January 1 st to March 15 th,2020.Results showed that compared with the normal production period,air quality in Jinan during the COVID-19 epidemic was significantly improved,the concentrations of pollutants(expect O 3)decreased,mainly due to the reduction of anthropogenic air pollutants,such as decrease of social and economic activity intensity,vehicle emission and so on.Radar charts showed that due to the influence of secondary aerosol,vehicle emissions,dust emission and coal combustion,the characteristics of air pollution wasn’t significantly changed during study period.SO^(2-)_(4),NO^(-)_(3) and NH+4 were the major water-soluble ions in PM 2.5 and mainly came from secondary reaction.Mass concentration ratio of NO^(-)_(3) and SO^(2-)_(4) ranged from 1.22 to 1.80,showing that PM 2.5 was mainly affected by vehicle emissions.PM 2.5 and relative humidity had a similar variation trend during study period,verified that high humidity could accelerate secondary transformation.