广州城区PM_(2.5)中水溶性有机碳浓度特征及其来源  

Characterization and Sources of Water-soluble Organic Carbon in PM_(2.5) at Urban Guangzhou

作　　者：瞿群[1] 张智胜[1] 刘随心[2] 朱李华[1] 

机构地区：[1]环境保护部华南环境科学研究所,广东广州510655 [2]中国科学院地球环境研究所,陕西西安710075

出　　处：《环境科学与技术》2015年第12期50-53,66,共5页Environmental Science & Technology

基　　金：国家环境保护公益性行业科研专项(200809143)

摘　　要：水溶性有机碳(WSOC)是碳气溶胶的重要组成部分,具有显著的环境与气候效应。该研究在广州城区采集了冬季和夏季PM_(2.5)日样品,分析了其中的水溶性有机碳、水溶性离子、有机碳(OC)和元素碳(EC)等化学成分,同步收集了臭氧(O_3)的浓度资料,并利用因子分析模型(FA)探讨了广州城区大气PM_(2.5)中WSOC的主要来源。结果表明,冬季和夏季WSOC的平均浓度分别为(9.2±6.2)μg/m^3和(5.2±3.1)μg/m^3,浓度处于较高水平。冬夏两季WSOC与基于EC示踪方法估算的二次有机碳(SOC)均有着显著的相关关系,且夏季WSOC与O_3亦呈现出显著的正相关关系,表明了广州城区观测的WSOC在夏季能较好地示踪SOC的污染程度。因子分析结果则进一步揭示了广州城区WSOC主要来源于SOC的生成和生物质燃烧,而其它污染源对其贡献较小。Water-soluble organic carbon（WSOC）constitute a major fraction of carbonaceous aerosol,and exert significant effects on environment and climate. Daily PM_（2.5）samples were collected at an urban site in Guangzhou during summer and winter. Samples were subjected to chemical analysis for various chemical components including WSOC,water-soluble inorganic ions,organic carbon（OC）and elemental carbon（EC）. Factor analysis（FA）model was further applied to investigate the sources of WSOC. The results showed that average concentrations of WSOC in winter and summer were（9.2±6.2）μg/m^3and（5.2±3.1） μg/m^3,respectively. Significant correlations between WSOC and the EC-based method estimated secondary organic carbon（SOC）were found in winter and summer. Moreover,positive correlation between WSOC and O_3 was found in summer. It indicated WSOC could represent the SOC during summer. The FA further revealed the secondary formation and biomass burning were the primary sources of WSOC in Guangzhou,while the contributions from other sources were limited.

关 键 词：水溶性有机碳 二次有机碳 O_3 来源 

分 类 号：X513[环境科学与工程—环境工程]