Evaluation of soil heavy metal pollution of farmlands surrounding industrial enterprises producing energy-saving bulbs

In order to explore the soil heavy metal pollution in the surrounding areas of enterprises producing energy-saving bulbs,102 topsoil samples were collected and analyzed in terms of Hg,As,Cu,Pb,Zn.Cd.Cr,Ni,Co and Mn contents,and the heavy metal pollution of soil was evaluated by single factor pollution index and Nemerow integrated pollution index.The spatial distribution of soil heavy metals was also analyzed by geostatistics methods.The results showed that the average contents of Hg,As,Cu,Pb,Zn,Cd,Cr,Ni.Co and Mn in the soil were 0.27,3.51,17.74,54.84,70.34,0.15,25.12,10.31,7.36 and 134.43 mg/kg respectively.not exceeding the secondary standards of the national soil environment;but the average Pb and Hg contents were over the soil background values of Zhejiang Province,being 80%and 69%higher than the soil background values respectively.The evaluation by single factor pollution index showed that the descending order of pollution degrees was PbHgCdZnCuCoAsCrNiMn.The evaluation by Nemerow integrated pollution index showed that 101 sampling points of soil were contaminated to different extents by heavy metals.and the proportions of light pollution,pollution and heavy pollution were 86.27%,9.80%and2.94%respectively.The soil pollution caused by both Pb and Hg heavy metals was relatively heavy,which somewhat corresponded to the spatial distributions of traffic and enterprises producing energy-saving bulbs.