Abstract:
In order to investigate the distribution characteristics of heavy metal pollution in soils under different land use types of surrounding industrial parks, the authors in this paper focused on typical smelting industry areas in Yunnan Province and took targets soils with various land uses as the study object.The contamination status of eight heavy metals in agricultural land, forest land, and wasteland was comprehensively evaluated by single pollution index method and potential ecological risk index.Correlation analysis and principal component analysis were utilized to explore the sources of pollution.The results indicate that the average content of Cd, Cr, Cu, Ni, Pb, Zn, Hg, As in soils of the study area all exceeded the background value of heavy metals in soils of Yunnan Province.Among the three land-use types, agricultural land exhibited a significant higher mean single pollution index (excluding Cr and Ni) and higher comprehensive potential ecological risk level compared with forest land and wasteland. The overall comprehensive potential ecological risk level for heavy metals in the entire region was classified as strong or extremely strong. A clear spatial pattern emerged, showing that the comprehensive potential ecological risk level generally decreased with increasing distance from the industrial park. Correlation analysis and PCA indicated that Cd, Pb, Zn, Hg, As, Cu were primarily derived from industrial sources for forest land and wasteland, and Cd, Pb, Zn, Hg, As, Cu were superimposed with agricultural sources for agricultural land. Cr and Ni were mainly controlled by the soil parent material. Understnding of the dynamic changdes in heavy metal concentrations as well as the rationality regarding land utilization methods could be strengthened throug the research, and it could provide scientific basis and guidance for preventing soil heavy metal pollution in this area.