Heavy Metal Pollution in Different Types of Land Use in Baiyangdian Lake

Based on the study of soil samples collected from reed field, poplar plantation, corn field and foul land in Baiyangdian Lake, we investigated the distribution of heavy metal pollutions including Cd, Cr, Cu, Ni, Pb and Zn which seriously threaten soil environment and human health. These following conclusions have been reached: Cr, Cu, Ni, Pb and Zn in different types of land use was concentrated in the soil layer of 0-40 cm, the content of Cr, Cu, Ni, Pb and Zn decreased with land depth. The highest concentration of heavy metals presented at 0-20 cm in the reed field, whereas the others at 20-40 cm. The reason may be that the local residents turned deep soil to the surface land for enhancing soil fertility in these land uses in former years. The average concentration of Cr, Cu, Ni, Pb, and Zn is similar in reed field, poplar plantation and corn field, and it is higher than foul land obviously. The concentration of Cd is similar in four types of land use, and the content tends to increase with land depth. Cd tends to concentrate in deep soil. These conclusions can provide some basis to control heavy metal pollution in Baiyangdian Lake in future. Because only the content of Cd element exceeds the Standard of Soil Environmental Quality (GB 15618-1995), the pollution control of Cd should be the key point.