辽河口湿地表层土壤中PAHs的源解析研究

摘要

Thirty one topsoil samples were collected from Liaohe estuary wetlands in October of 2008, and May and August of 2009.Polycyclic aromatic hydrocarbons (PAHs) were quantified with GC-FID.The distribution of PAHs showed temporal variations.The concentrations of PAHs in October (1001.9 ng/g) were higher than that in May (877.1 ng/g) and August (675.4 ng/g).Diagnostic ratio analysis illustrated that pyrolysis was the main source of PAHs in October,and the mixed pollution of pyrolysis and oil spill was the dominant PAHs source in May and August.The positive matrix factorization analysis (PMF) indicated that the main sources of PAHs were coal combustion, traffic emission and biomass burning in October with contributions of 26％, 21％ and 20％, respectively.Oil/traffic emission, oil spill and biomass burning, with contributions of 33％, 24％ and 17％, respectively, were the main PAH sources in May of 2009.In August,oil spill with a contribution of 37％ was dominant, followed by a mixture of traffic emission and biomass burning, coal combustion, coke oven and vehicular emission, with contributions of 19％, 16％, 14％ and 14％, respectively.%分别于2008年10月,2009年5月和8月采集31个辽河口湿地表层土壤样品,利用GC-FID技术定量分析其中多环芳烃(PAH)含量.结果表明,PAHs呈现出一定的时间分布特征,10月份的PAHs平均含量为1001ng/g,高于5月(877.1ng/g)和8月(675.4ng/g).应用比值法识别土壤PAHs主要来源,结果显示,2008年10月主要源于燃烧源,并表现出油类、生物质和煤的燃烧为主要来源的特征;2009年5月和8月均表现出石油源和燃烧源的混合源.正定矩阵因子模型解析结果表明,燃煤、交通燃油和生物质燃烧在2008年10月的贡献率最高,分别为26%、21%和20%.石油与交通污染、石油污染和生物质燃烧是2009年5月最重要的3种污染源.贡献率依次为33%、24%和17%.2009年8月以石油污染和交通污染与生物质燃烧混合源的贡献率最高,贡献率分别为37%和19%.