2014—2017年济南市大气PM2.5及其成分变化研究

Variation of atmospheric PM2.5 and their components in Ji’nan during 2014-2017

目的探讨济南市近年大气PM2.5浓度及其成分变化,为城市环境治理提供科学依据。方法于2014年1月至2017年12月在济南市选择市中区和历城区2个监测点,采集大气PM2.5,检测PM2.5质量浓度及其金属、非金属元素、水溶性离子、多环芳烃(PAHs)含量。结果共采集济南市市中区和历城区监测点PM2.5样品733份,2014—2017年两地区大气PM2.5浓度均有下降趋势,差异有统计学意义(P<0.05)。大气NO3-、SO42-、Cl-浓度均有下降趋势,差异有统计学意义(P<0.05)。济南市大气PM2.5中含量较高的元素是铝、铅、锰、硒、砷,2017年市中区大气中镍、砷、硒、镉、铅等元素浓度较之前的部分年份明显下降,PM2.5中铝、铬元素含量2017年较2015、2016年明显升高,差异有统计学意义(P<0.05)。大气PM2.5中浓度较高的PAHs为苯并(b)荧蒽、茚并(1,2,3-cd)芘、苯并(g,h,i)芘、屈、荧蒽等。历城区大气PM2.5中砷、硒、镉、锑、铅浓度均较之前年份有不同程度下降。结论近年来济南市大气质量改善明显,但污染依然较重。降低工业污染等环境措施具有一定效果,但扬尘治理效果有待提高,来自汽车等移动污染源的排放有增加趋势。

Objective To understand the variation of the concentration of PM2.5 and its components in Ji’nan and provide scientific basis for environmental management.Methods During 2014-2017,two monitoring points were chosen in Licheng district and Shizhong district in Ji’nan,and the concentration of PM2.5,metals,metalloids,water soluble ions,polycyclic aromatic hydrocarbons in PM2.5 were determined.Results A total of 733 samples were collected during 2014-2017,the concentration of PM2.5 in Licheng district and Shizhong district decreased(P<0.05),and the concentration of NO3-,SO42-and Cl-in PM2.5 decreased significantly from 2014 to 2017(P<0.05).The elements with higher concentration in PM2.5 were Al,Pb,Mn,Se and As;In 2017,the concentrations of Ni,As,Se,Cd and Pb in PM2.5 decreased significantly than past years,Al and Cr increased compared with those in 2015 and 2016 in Shizhong district;The concentrations of As,Se,Cd,Sb and Pb in PM2.5 in 2017 decreased than past years in different degrees in Licheng district.The contents of BbF,Ipy,BPE,Chr and Flt in PM2.5 were higher.Conclusion In recent years,air quality has been improved obviously,but air pollution is still heavy in Ji’nan.Measures to reduce industrial pollution is efficient,and dust control should be strengthened,and the emissions from cars and other mobile sources also present increasing trend.