兰州城区大气PM_(2.5)污染特征及来源解析  

Pollution Characteristics and Source Apportionment of PM_(2.5) in Lanzhou City

作　　者：王新[1] 聂燕[1] 陈红[1] 王博[2] 黄韬[3] 夏敦胜[1] 

机构地区：[1]兰州大学资源环境学院西部环境教育部重点实验室,兰州730000 [2]中国科学院寒区旱区环境与工程研究所,兰州730000 [3]兰州大学资源环境学院,兰州730000

出　　处：《环境科学》2016年第5期1619-1628,共10页Environmental Science

基　　金：中央高校基本科研业务费专项(lzujbky-2013-m03;lzujbky-2015-225)

摘　　要：为探究兰州城区PM_(2.5)的污染特征及其来源,分别在兰州市城关区和西固区设置PM_(2.5)采样点,于2013年10月(非采暖期)和12月(采暖期)采集样品并进行分析,得到了PM_(2.5)及其16种化学组成的质量浓度.结果表明,兰州城区PM_(2.5)污染水平较高,平均质量浓度为129μg·m^(-3).样品无机元素平均质量浓度为:S>Ca>Fe>Al>Mg>Pb>Zn>Mn>Ti>Cu,其中S、Ca、Fe、Al的质量浓度在1μg·m^(-3)以上,是主要元素组分;样品各无机元素质量浓度表现为采暖期高于非采暖期,城关区高于西固区.样品水溶性离子平均质量浓度为:SO^(2-)_4>NO^-_3>NH^+_4>Cl^->K^+>Na^+,其中SO^(2-)_4、NO^-_3、NH^+_4的质量浓度在10μg·m^(-3)以上,是主要离子组分;样品各水溶性离子质量浓度表现为采暖期高于非采暖期,西固区高于城关区.富集因子(EF)分析结果表明,元素Al、Ca、Mg、Ti的EF值均小于1以自然来源为主;元素Cu、Pb、S、Zn的EF值显著大于10,表明这4种元素在PM_(2.5)中高度富集,且主要源于人为活动造成的污染.主成分分析结果表明,交通排放源、生物质燃烧源、土壤源和二次粒子对兰州城区大气PM_(2.5)贡献显著.In order to understand the characteristics and sources of PM2.5pollutant in Lanzhou City,two PM2.5sampling sites were set up in Chengguan district and Xigu district,respectively. Samples were sampled during October（ non-heating period） and December（ heating period） 2013,and mass concentrations of PM2.5and its 16 kinds of chemical components were analyzed. The results showed that the average mass concentration of PM（2.5during the sampling period was 129 μg·m^-3. The sequence of mass concentrations of inorganic elements was： S〉 Ca〉 Fe 〉Al 〉Mg 〉Pb〉 Zn〉 Mn〉 Ti〉 Cu,while the mass concentrations of S,Ca,Fe,and Al,which were the major element compositions,exceeded 1 μg·m^-3. The mass concentration of inorganic elements during heating period was higher than that during non-heating period,meanwhile,the mass concentration in Chengguan district was higher than that in Xigu district. The sequence of mass concentrations of water-soluble ions was： SO^2-4〉 NO^-3〉 NH^＋4〉 Cl^-〉 K^＋〉 Na^＋,while the mass concentrations of SO^2-4,NO^-3,NH^＋4,which were the main ion components,exceeded 10 μg·m^-3. The mass concentration of watersoluble ions during heating period was higher than that during non-heating period,meanwhile,the mass concentration in Xigu district was higher than that in Chengguan district. The result of enrichment factor（ EF） analysis showed that the EF values of Al,Ca,Mg and Ti were lower than 1,indicating the contribution of natural source,while the EF values of Cu,Pb,S and Zn were higher than 10,indicating the contribution of anthropogenic pollution. The result of principal component analysis showed that the sources of PM2.5were mainly derived from traffic emission,biomass burning,soil and secondary particles.

关 键 词：兰州 PM2 5 污染特征 富集因子 主成分分析 

分 类 号：X513[环境科学与工程—环境工程]