城市建筑物对周围土壤中多环芳烃含量与分布的影响

为探讨城市建筑物对其周围土壤中多环芳烃(PAHs)含量与分布的影响,对建筑物勒脚或散水边缘(B)和距建筑物5m(B-5)处20个表层土壤样品中16种优控PAHs进行了检测分析.结果表明,B处土壤中?16PAHs含量为824~8960ng/g,平均为2649ng/g;B-5处土壤中?16PAHs含量为637~1706ng/g,平均为1297ng/g,B处PAHs含量远高于B-5.各样点主要以4环和5环PAHs为主,B处3环PAHs含量高于B-5处.其中?4PAHs(Fl、Pyr、InP和BghiP)含量分别占B和B-5土壤中?16PAHs的48%和45%.参照Maliszewska-Kordybach建立的土壤PAHs污染标准,HJ-5、AJ、AJ-5、EB-5和TC-5属于中等污染程度(600~1000ng/g),其余各样点均属于重度污染(>1000ng/g).B处土壤中TOC相对B-5处有富集趋势,B和B-5处土壤中PAHs与TOC无明显的相关性.BaA、Chry、B(b/k)F、BaP、InP和DahA是B 和B-5处土壤中TEQBaP浓度的主要贡献者.溯源结果表明B和B-5处土壤中PAHs主要来源于煤炭、汽油和柴油的燃烧; B-5土壤中PAHs部分可能来源于石油类的泄漏.

Effects of city buildings on content and distribution of polycyclic aromatic hydrocarbons in adjacent soil

Sixteen priority control polycyclic aromatic hydrocarbons (PAHs) were analyzed in twenty surface soil samples collected from the plinth or aproll edges of the building (B) and 5-meter sites away from the building (B-5), to discuss the impacts of urban buildings on the level and distribution of PAHs from the surrounding soil. The results showed that the concentration of PAHs ranged from 824 to 8960 ng/g in soil at B, with an average of 2649ng/g, PAHs in B-5 varied from 673 PAHs in to 1706ng/g with an average of 1297ng/g which were significantly lower than that of site B. The distribution profile of PAHs was mainly dominated by 4~5ring PAHs in the study area. Fl, Pyr, InP and BghiP in soil were dominant species both at B and B-5and accounted for 48% and 45% of total mass PAHs, respectively. HJ-5, AJ, AJ-5, EB-5and TC-5were in the moderate degree of pollution(600~1000ng/g), and the others were categorized heavily polluted (>1000ng/g) by reference to Maliszewska-Kordybach soil standard. Soil TOC exhibited the trend of enrichment at B relative to at B-5, and there was no clear correlation with PAHs. BaA, Chry, B(b+k)F, BaP, InP, and DahA were major contributor to TEQBaP concentration. The source apportionment showed that soil PAHs at B and B-5are mainly originated from coal, gasoline and diesel combustion, and PAHs at B-5might be partly from oil spill.