福州市农业土壤多环芳烃的含量、来源及生态风险

Concentrations,Sources and Ecological Risks of Polycyclic Aromatic Hydrocarbons in Agricultural Soils of Fuzhou City

研究了福州市农业表层土壤（0-10cm）。中美国环境保护署（USEPA）优控的16种多环芳烃（PAHs）含量，并对其来源和生态风险进行了分析。结果表明，供试土样中16种PAHs检出率达到100％，其总量的含量范围为100.2-1215.1μgkg^-1，且与土壤总有机碳的含量呈显著正相关；土壤中PAHs主要源于生物燃烧和石油。利用毒性当量因子（TEF）计算了供试土样中PAHs单体相对于苯并[a]芘的毒性当量（Bapeq），土样中总Bap。值的范围为12.50-147.95μgkg^-1，其中50％土样总Bapeq的值超过荷兰规定目标值（总Bapeq=32.96μgkg^-1），表明福州市部分农业土壤存在一定的潜在生态风险。

The content of 16 kinds of PAHs, which were on the list of USEPA priority, of agricultural surface soils （at the depth of 0-10cm） of Fuzhou city was studied, together with the sources and ecological risks of these PAHs. It was demonstrated that, in all soil samples, 16 PAHs could be detected out. The total concentration of the 16 PAHs in the sampling soils ranged from 100.2μgkg^-1 to I 215.1μgkg^-1, and had significantly positive correlation with soil organic carbon concentrations （P〈0.01）. It was further discovered that the major sources of PAHs were petroleum and biomass burning. By the method of Toxic equivalent factor （TEF）, the toxicity value of every kind of the 16 PAHs was converted into equivalent toxicity value of benzo （a） pyrene （Bapeq）. The calculation indicated that the total Bapeq value of sampling soils fell in the range from 2.50μgkg^-1 to 147.95μgkg^-1, and in half of sampling soils, the total Bapeq value surpassed the Dutch target value （total Bapeq = 32.96μgkg^-1）, which showed that, to some extent, quite a part of agricultural soils in the city, were subjected to potential ecological risks.