Pollution characteristics of heavy metals in soil of lead-zinc mining in karst areas

This study focused on the heavy metals in soil in DX and DW lead-zinc areas. By using the methods of atomic absorption spectrometry (AA800), atomic fluorescence spectrometry(AF-640) and other instruments, we measured the contents of heavy metals,including zinc(as Zn), mercury(as Hg), chromium (as Cr),cadmium (as Cd),copper (Cu), nickel (Ni), lead (Pb)and arsenic (As).By means of the single-factor pollution index and Nemerow index methods,we compared the pollution characteristics in the soil.PPC statistics were used to analyze the correlation of heavy metal pollution in the soil.The results indicate that heavy metals in soil have caused single or complex pollution and the soil was heavily polluted by Cd in the two areas. The Nemerow indexes in these two areaare 27.61 and 63.54, respectively, implying that the soil was highly polluted and such contamination in the DW area was more serious than the DX area.Except for Ni, the other seven heavy metals in the DX are correlated with each other,which is likely related to polymetallic accompanying and symbiotic deposits in the mining area.The total content of heavy metals and the pH have no significant correlation in the soil. The established models show high fitting precision and the research results can provide evidence for rehabilitating the polluted land in mine areas and setting corresponding management measures.