摘要；本文采集了江苏省徐州市某焦化厂和某农田的土壤样品，通过对焦化土和农业土进行室内培养, 并对样品中的土壤酶活性进行了测定。结果表明，多环芳烃污染的焦化土壤中多环芳烃对土壤脲酶活性有先抑制后激活作用,对过氧化氢酶有先激活后抑制作用，脲酶和过氧化氢酶活性可以作为多环芳烃污染土壤的生态毒性指标。

关键词:多环芳烃; 污染土壤; 酶活性; 

Abstract：The paper collected  a coking plant and a farmland soil sample of Xuzhou City, Jiangsu Province, Indoor cultivation of coking soil and agricultural soil, And samples of soil enzyme activity were determined. The results showed that, Polycyclic aromatic hydrocarbons in coking soil polycyclic aromatic hydrocarbons in soil urease activity were inhibited activation of the first activation after inhibition of catalase. Urease and  catalase activity can be used as indicators of ecotoxicity of PAHs contaminated soil.

Key words : polycyclic aromatic hydrocarbons ( PAHs) ; contaminated soil; enzymatic activity.