关键词: 重金属, 污染, 5%HNO3溶液, 浸提, 土壤, 污染物

Abstract: Based on the methods of environmental geochemistry, an investigation was carried out on the soil contamination from heavy metals in the multiplex metal mining area and adjacent tilled land in West Liaoning Coastal Zone. The result indicates that highest contents in mass fraction of Cu, Pb, Zn and Cd are up to 0.0236%, 0.0535%, 0.1473% and 0.0012%, respectively. The contents in mass fraction of Cu, Pb, Zn and Cd in top soil are mostly higher than the corresponding background values of the zone, i.e., 1.34-10.67, 1.20-25.59, 0.49-23.31 and 1.87-82.8 times as larger as the background values, respectively. It is proved that there is a comparatively close exponential correlation between the mass fraction of the four elements and those of them leached out in 5% HNO3 solution. In the zone the sources of soil contamination from heavy metals are mainly the free dust during mining, tailings and waste sludge, and the mass fractions of such heavy metals in top soil decrease with the increasing distance away from the contamination sources.