Abstract:

Anthropogenic polycyclic aromatic hydrocarbons (PAHs）are one of the most major pollutants in soil under coking plants.In order to understand the characteristics of accumulation and vertical distribution of 16 USEPA priority PAHs in soil, GC/MS was used to analyze 16 PAHs in 587 soil samples taken from different depths of 0—18 m under coking plant.The results showed that, the highest and average concentration of total PAHs were 14363.7 mg·kg^-1 and 190.4 mg·kg^-1 respectively, indicating that the soil under coking plant had been polluted.The dominant components were low molecular weight PAHs, accounting for about 85%.The concentrations of PAHs had obvious fluctuation at various layers, and their concentration change was parallel.There was an obvious cumulative effect in 5—6 m soil layer, which might be due to different filtration capability of soil in different layers and PAHs leaching ability.Based on the principal component and Q-clustering analysis, the entire soil profile could be classified into 5 different layers：0—1 m, 1—3 m, 3—5 m, 5—