CHARACTERISTICS OF SOIL HEAVY METAL POLLUTION AND ECOLOGICAL RISK ASSESSMENT OF JINZHOU CITY

Taking Jinzhou City as the study area, the paper analyzes the pollution characteristics of 8 soil heavy metals including As, Cd, Hg, Cr, Cu, Pb, Zn and Ni, and uses the methods of single factor pollution index, geoaccumulation index, Nemerow comprehensive index and Hakanson potential ecological risk index to determine the degree of soil heavy metal pollution and evaluate the potential ecological risk. The results show that the contents of Cd and Cr in soil are higher than the soil background values of China and Liaoning Province, and the contents of Cu, Hg, Ni and Pb also higher than the soil background values of the province. The single factor index evaluation results reveal Cd is at moderate pollution level, while Hg, Pb, Cr, Ni and Cu mild pollution. The geoaccumulation index evaluation results reflect Cd is at light-moderate pollution level and other heavy metals pollution-free. The average Nemerow comprehensive pollution index is 2.25, indicating a moderate pollution grade. The average comprehensive potential risk index is 157.34, suggesting the study area is at moderate ecological risk. Cd and Hg contribute to high potential ecological risk in parts of the area.