摘要
为探究重污染天气期间济南市城区和清洁对照点PM2.5及其组分污染特征,于2016年12月31日-2017年1月7日在市监测站和跑马岭进行连续PM2.5样品采集,并对两个点位的PM2.5及其组分(水溶性离子和碳质组分)污染特征进行分析。结果表明,重污染天气期间市监测站PM2.5质量浓度(260±77)μg·m^-3是跑马岭(85±17)μg·m^-3的3倍,表明该重污染天气过程对济南市城区影响程度明显大于清洁对照点跑马岭。市监测站水溶性离子浓度高低顺序为SO4^2->NO3^->NH4^+>Cl^->K^+>Na^+>Ca^2+>F^-,跑马岭水溶性离子浓度高低顺序为NO3^->SO4^2->NH4^+>Cl^->K^+>Na^+>Ca^2+>F^-。市监测站和跑马岭二次无机离子(SNA)质量浓度分别为(134.7±49.5)μg·m^-3和(46.2±19.0)μg·m^-3,在PM2.5中占比分别是51.8%和54.4%,两个点位PM2.5浓度差别很大,但SNA在PM2.5中占比相差不大。通过NH4^+计算值与实测值相关性分析可知,市监测站和跑马岭PM2.5中NH4^+均主要以(NH4)2SO4和NH4NO3形式存在。市监测站SOR和NOR分别为0.44和0.32,跑马岭SOR和NOR分别为0.32和0.44,SOR和NOR的值均大于0.1,表明大气中SO2和NO2的二次氧化程度较高。采用OC/EC最小比值法估算得到市监测站和跑马岭SOC分别为8.3μg·m^-3和1.8μg·m^-3,分别占OC的38.2%和20.9%,这表明市监测站OC二次反应程度明显高于跑马岭。市监测站有机碳(OC)和元素碳(EC)相关性(R2=0.57)明显弱于跑马岭(R2=0.92),表明市监测站OC和EC来源比较复杂,更有利于SOC的生成。
To investigate PM2.5 and its components pollution characteristics in Jinan urban area and clean air site during the period of heavy air pollution weather,the continuous collection of PM2.5 were performed from December 31 2016 to January 7 2017 at the Environmental Monitoring Center and Paomaling.Also,the characteristics of PM2.5 and its pollution components(water-soluble ions and carbonaceous components)were analyzed.Results showed that the concentration of PM2.5 at the Environmental Monitoring Center was three times as many as which at Paomaling,implying the impact of heavy air pollution weather on Jinan urban area was significantly stronger than that of Paomaling.The order of water-soluble ion concentrations in PM2.5 collected at the Environmental Monitoring Center was SO4^2->NO3^->NH4^+>Cl^->K^+>Na^+>Ca^2+>F^-,while at Paomaling it was NO3^->SO4^2->NH4^+>Cl^->K^+>Na^+>Ca^2+>F^-.The concentration of SNA was(134.7±49.5)μg·m^-3(51.8% of PM2.5)at the Environmental Monitoring Center and(46.2±19.0)μg·m^-3(54.4% of PM2.5)at Paomaling,respectively.The two sites showed a great difference in PM2.5 concentrations,but a close proportion of SNA in PM2.5.By analyzing the correlation between the calculated and measured concentrations of NH4^+,it could be confirmed that NH4^+mostly existed in the forms of(NH4)2SO4 and NH4NO3.At the Environmental Monitoring Center,sulfate oxidizing rate(SOR)and nitrate oxidizing rate(NOR)were 0.44 and 0.32,while at Paomaling SOR was 0.32 and NOR was 0.44.Both SOR and NOR were over 0.1 at the two sites,suggesting a high level of secondary oxidation of SO2 and NO2.By using the OC/EC minimum ratio method,the secondary organic carbon(SOC)was estimated to be 8.3μg·m^-3(38.2% of OC)at the Environmental Monitoring Center and 1.8μg·m^-3(20.9% of OC)at Paomaling,indicating that the level of secondary reaction of organic carbon at the Environmental Monitoring Center was much higher than that at Paomaling.The correlation between EC and OC at Paomaling(R2=0.92)was stronger than that at Environme
作者
夏志勇
付华轩
吕晨
张文娟
李敏
孙凤娟
XIA Zhiyong;FU Huaxuan;LV Chen;ZHANG Wenjuan;LI Min;SUN Fengjuan(Ji'nan Environmental Monitoring Center,Ji'nan 250014,China)
出处
《生态环境学报》
CSCD
北大核心
2019年第5期958-963,共6页
Ecology and Environmental Sciences
基金
山东省重点研发计划项目(2015GGH301002)
山东省省级环保产业技术研发项目(SDHBYF-2012-01)
关键词
PM2.5
水溶性离子
碳质组分
污染特征
PM2.5
water-soluble ions
carbonaceous components
pollution characteristics
