[Pollution Properties and Ecological Risk Assessment of Heavy Metals in Farmland Soils and Crops Around a Typical Manganese Mining Area].

In order to assess the ecological risks of heavy metals and explore the pattern of heavy metal migration between farmland and corresponding crops in a typical and closed manganese mining area in Hunan province, farmland soils and crops surrounding the mining area (pollution area) and away from the mining area (control area) were collected, and then the contents of Cr, Mn, Ni, Cu, Zn, As, Cd, and Pb were analyzed. The sources and distribution of heavy metals in farmland soils were analyzed using Kriging spatial interpolation and principal component analysis, and the ecological risk was evaluated using the single factor index, comprehensive pollution index, and potential ecological risk index. The results showed that the surrounding farmland soils in the closed Manganese mining area presented serious pollution of Cd, Zn, As, and Mn, in which the average contents of the above heavy metals in the dry land soil in the polluted area were 6.