中文摘要：

PAHs的性质使其容易在土壤中富集,且因难降解和毒性大而成为土壤污染治理的重点。本研究测试了北京市东南部地区土壤和地下水中的PAHs含量,同时对近年来北京平原区土壤中PAHs的其它监测数据进行了联合分析。研究结果表明：（1）北京市平原区土壤中16种PAHs的平均值为936.9μg/kg,处中度污染水平且接近重度污染;（2）土壤中PAHs的来源表现出一定的地带分布规律,其中林地和果园的污染源主要为石油输入源,其它区域的污染源主要为不同类型的燃烧源（木材、煤、石油、汽油等）或混合源;（3）地下水中PAHs的种类明显比土壤中的少,但是以具较强毒性的二环和三环PAHs为主,主要原因为低环的PAHs主要以溶解态形式在土壤中迁移,容易进入浅层地下水。

英文摘要：

Human activities have led to soil contamination,and PAHs is the key because of its peculiar properties called recalcitrance and toxicity.The soil samples in the southeast of Beijing are collected and tested combined with the statistics data of PAHs in Beijing Plain in recent years.The result indicates that（1）∑PAHs residues in the study area are at the medium level of averaged 936.9 μg /kg,but the content of PAHs varies greatly in different places.（2） The content of PAHs in the soil follows a certain pattern that PAHs in forest land and orchards are mainly from oil or partly from soil organic matter and PAHs in the other areas are mainly from combustion sources.（3） The migration of 2,3-PAH can easily occur in the dissolved state and contribute to groundwater pollution.