Characteristics and Assessment of Soil Heavy Metal Pollution under Different Land-use Types in the Baiyangdian Wetland

  Objective  Baiyangdian is the important part of Xiong An’s ecological community. In the Baiyangdian Ecological Environment Management and Protection Plan, the land will be submerged. In order to evaluate the environmental impact of the submerged land on the Baiyangdian water body, this paper has carried out research work from two aspects: the characteristics of soil heavy metals and the evaluation of pollution degree.

  Method  The contents of As, Hg, Cd, Cr, Pb, Ni and Cu in 0-20 cm soil of different land-use types in Baiyangdian were determined, and the features and pollution levels by the heavy metals were assessed with the methods of statistical analysis, pollution load index and geoaccumulation index.

  Result  The results showed that the background values of heavy metals on the lands in Baiyangdian wetland were higher than those on the regional background value. The degree of pollution was generally light. The heavy metals of Cu, Cd and Hg were higher than those of background value and were the most significant polluted elements in the top soil.

  Conclusion  The heavy metals of the land surface soil have not yet reached the soil screening or control standards, and the environmental carrying capacity still has a certain buffer capacity. The correlation characteristics among heavy metals are mainly controlled by geological background factors, but they are also obviously affected by land-use types.