表层岩溶带土壤中多环芳烃分布特征及来源解析  

Distributing features and source analysis of polycyclic aromatic hydrocarbons in epikarst soils

作　　者：孙玉川[1] 沈立成[1] 袁道先[1,2] 

机构地区：[1]西南大学地理科学学院/三峡库区生态环境教育部重点实验室,重庆400715 [2]中国地质科学院岩溶地质研究所/国土资源部、广西壮族自治区岩溶动力学重点实验室,广西桂林541004

出　　处：《中国岩溶》2013年第1期79-87,共9页Carsologica Sinica

基　　金：重庆市科委院士专项(CSTS,2010BC7004);国家自然科学基金项目(41072192);西南大学博士基金项目(SWU110258)

摘　　要：利用气相色谱-质谱联用仪(GC-MS)对表层岩溶泉域土壤中的16种优控的多环芳烃(Polycyclic Aromatic Hydrocarbons,PAHs)含量进行了分析,并对其组成、污染水平和来源进行了探讨。结果表明,16种优控PAHs在表层岩溶泉域土壤中的检出率为100%,其含量介于439.19～3 329.72ng/g之间,平均值为1 392.44ng/g,7种致癌性PAHs占总量的26%。PAHs的组成特征受地形的控制,随着海拔升高,低环PAHs所占比例升高,高环PAHs比例降低。同分异构体比值分析表明,研究区土壤中的PAHs主要来自于煤、生物质和石油的燃烧排放。研究区土壤中16种PAHs的TEQcarc值介于18.65～501.13ng/g,平均值为140.57ng/g。7种致癌性PAHs占总TEQcarc的比例达到96.8%。研究区表土中,后沟泉域的污染程度最大,次之是兰花沟泉域和柏树湾泉域,水房泉泉域的污染程度最小,但由于柏树湾泉域松针落叶中BaP、PAHs含量较高,松针落叶中PAHs含量分别高达36.36ng/g和2 370.1ng/g,土壤生态风险评价中应考虑松针落叶层的潜在影响。The concentration o[ 16 prior polycyclic aromatic hydrocarbons（PAHs） are measured by gas chro- matography equipped with a mass spectrometry detector for samples collected from the overlaying soils of four typical epikarst springs that located in Nanchuan District, Chongqing City. The distribution, possible sources and contaminated level of the 16 PAHs are investigated. The detection ratios of the 16 PAHs are 100 ~ in all of the soil samples. The total concentration of the 16 PAHs in the soils range from 439.19 to 3 329.72 ng/gwith the mean value being 1 392. 44 ng/g. The PAH constituents are affected by altitude. With the increase of altitude, the percent of low molecular weight PAHs increase, but the percent of high molecular weight PAHs decrease. The isomer ratios reveal that PAHs in soils mainly come from the com- bustion of coal, biomass and petroleum. The TEQ of the 16 PAHs range from 18.65 to 501.13 ng/g, the mean value is 140.57 ng/g, and 96.8 ~ of which is contributed by 7 carcinogenic PAHs. Among the soils of the four epikarst spring, the level of PAHs contamination in HG epikarst spring soils is highest, and the contamination level of SF epikarst spring soils are lowest, but in BSW soils, the effect of pine needle litter fall should be taken into account.

关 键 词：表层岩溶泉 土壤 多环芳烃 来源 

分 类 号：X142[环境科学与工程—环境科学]