Evaluation and Source Apportionment on Potentially Toxic Elements Pollution of Agricultural Soil in Mango Planting Areas in Panzhihua City, China

Heavy metal pollution in agricultural soil has a wide range of sources and an enormous scope of influence, bringing about severe environmental risk. In this study, we used Pearson correlation analysis, combined with principal component and cluster analysis (PCA/CA) to comprehensively analyze the sources of soil heavy metal contamination in a mango plantation area in Panzhihua City. We performed a spatial distribution of heavy metal contamination levels via ArcGIS for single factor and Nemerow Contamination Index. The results showed that PTEs exceeded background values of soil pollution in Sichuan Province. The enrichment of Cr, Ni and Zn were caused by the development of local industry. Cu is mainly from atmospheric dust. Various pollution sources controlled the accumulation of Cd, whereas that of As and Pb were related to agricultural activities and transportation. The spatial distribution of the pollution indices indicated that the soil in the study area was mild to severe pollution with compound PTEs. Chemical speciation analysis showed that the ecological risk of PTEs enrichment in the study area was slight. This study highlights the geographic distribution of heavy metal contamination levels and source resolution, providing targeting for local regulatory authorities to improve soil environmental quality.