Evaluation of heavy metal contamination and its potential ecological risk to the soil in Donghai Island new area, Zhanjiang

In order to determine the concentration of heavy metals in the soils of Donghai Island new area, Zhanjiang, and the associated potential ecological risk, 40 soil samples in cultivated land and woodland were obtained and analyzed for Pb, Zn ,Cu, Cd and Cr . Two indices-the Index of Geoaccumulation and the Potential Ecological Risk Index-were used to evaluate the degree of pollution by heavy metals. The results showed that the soils in the research area were polluted by heavy metals Cd ,Zn and Pb, and their concentrations were all above the background values. The soils in cultivated land are characterized by no to moderate pollution and pose a light potential ecological risk. The soils in woodland are characterized by moderate to high pollution and pose a moderate potential ecological risk The relative degree of pollution was in the order of Cd>; Zn >; Pb >;Cu>; Cr; and the potential ecological risk was characterized by the order of Cd>;Pb >;Cu≈Zn >;Cr, with the predominant risk factor being Cd. In general, the soils within the woodland pose greater potential ecological risk than those in cultivated land.