冬季兰州城市大气PM_(2.5)中碳气溶胶的污染特征  

Pollution characteristics of carbonaceous aerosols in PM_(2.5) during winter in Lanzhou

作　　者：李刚[1] 石广玉[2] 李宏宇[1,3] 邓祖琴[1] 

机构地区：[1]中国气象局兰州干旱气象研究所/甘肃省干旱气候变化与减灾重点实验室/中国气象局干旱气候变化与减灾重点开放实验室,兰州730020 [2]中国科学院大气物理研究所LASG国家重点实验室,北京100029 [3]南京大学大气科学学院气候与全球变化研究院,南京210008

出　　处：《中国科学院大学学报（中英文）》2014年第3期439-443,共5页Journal of University of Chinese Academy of Sciences

基　　金：甘肃省自然科学基金(1010RJZA001);甘肃省气象局重大科研项目(2010-15);干旱基金(IAMKY200801)资助

摘　　要：为深入探讨冬季兰州城市大气中碳气溶胶的污染特征,于2011年12月5—12日采集兰州城市大气PM2.5样品,利用DRI-2001A热/光碳分析仪测量元素碳(EC)和有机碳(OC)的浓度.结果显示:EC和OC的平均质量浓度分别为7.48μg/m3和22.71μg/m3.降雪是EC和OC浓度变化的主要因素.EC和OC的相关系数达到0.98,表明冬季兰州城市大气PM2.5中碳气溶胶的污染来源相对简单且基本相同.二次有机碳(SOC)的质量浓度是3.26μg/m3,仅占OC含量的14.4%,揭示出冬季兰州城市大气PM2.5中OC的主要来源是直接污染源.对碳气溶胶8种组分的因子分析结果表明,燃煤和机动车尾气的排放对冬季兰州城市大气PM2.5中碳气溶胶的污染有最主要的贡献.For studying the concentration characteristics and sources of carbonaceous aerosols during winter in Lanzhou, daily PM2.5 samples were collected during the period from 5 Dec to 12 Dee in 2011. Elemental carbon （EC） and organic carbon （OC） were measured by the thermal/ optical method using DRI-2001A. The results indicated that the average mass concentrations of EC and OC were 7.48 and 22.71μg/m3 , respectively, during winter in Lanzhou. Snow had significant effect on the ambient concentrations of EC and OC. The correlation coefficient between EC and OC was 0.98,which revealed that the emission sources of carbonaceous aerosol were relatively simple during winter in Lanzhou and EC and OC had the same sources. Mass concentration of SOC was 3.26μg/m3 , and it was only 14.4% of the concentration of OC in PM2.5. Factor analysis on the eight carbon fractions of carbonaceous aerosol indicated that coal combustion and vehicle emissions were the major sources for carbonaceous aerosol in PM2.5.

关 键 词：大气细粒子 元素碳 有机碳 二次有机碳 因子分析 

分 类 号：X513[环境科学与工程—环境工程]