葫芦岛市连山区·龙港区土壤重金属垂直分布与迁移特征

Vertical Distribution and Immigrant Character of Heavy Metals in Soil in Lianshan and Longgang Districts of Huludao City

用土壤地理信息系统中套合采样方法布置剖面点5个,对葫芦岛市连山区、龙港区地区各层土壤中Zn、Cd、Cu、Pb、Cr、Ni的的重金属含量进行了分析.探讨并改进了计算重金属迁移率的公式.结果表明,表土层的重金属含量明显高于20cm以下土层的重金属含量,体现强烈的表聚性.不同的重金属元素在不同的土层深度形态分布是不同的,随着土层深度的增加交换态Cd、Pb含量明显下降,残渣态Cu、Cd和Pb的比例则明显提高.同一剖面点CA的迁移率明显高于其他元素,而Pb在土壤中的迁移性较差.所有元素迁移的深度均未达到60～80cm.

By using overlay sanrpling method in GIS system to dispose 5 sites of soil profdes, the contents of heavy metals of Zn, CA, Cu, Pb, Cr and Ni in different layers of soil in lianshan and longarg districts of Huludao city were analyzed to discuss and improve the formula of computing the inmaigrant ratio of heavy metal. The results indicated that content of heavy metal in topsoil was higher than that in the soil below 20 cm, showing strong surface ag- ~_gation. The different elements of heavy metal were different in morphological distribution of different soil depth. With the increase of soil depth the content of Cd and Pb as the exchange form obviously descend and the content of Cu, Cd and Pb as the residue forms obviously increased, The immigrant ratio of Cd in same profile was evidently higher than other heavy metal and that of Pb was lower. The immigrant depth of all the dements didn＇ t reach to 60 - 80cm.