不同地区城郊用地土壤重金属含量特征的比较

对京津唐、张家港和长株潭3个地区的露天菜地、设施菜地、水田和旱地进行的调查表明,城郊区大部分农田土壤重金属含量尚低于国家相关的土壤质量二级标准,但部分重金属含量超出了当地背景值,说明重金属在城郊土壤中有所积累。菜地土壤重金属含量总体上要高于水田和旱地,说明高强度利用投入会导致土壤重金属累积。对长株潭一个污染区的研究表明,发生污染的土壤很难再恢复利用。京津唐城郊区的土壤重金属含量的变异系数总体上高于张家港地区。

Comparison of soil heavy metal pollution in suburb fields of different regions

In this paper, on the base of the investigation of open vegetable fields, facility vegetable fields, dry fields and paddy fields in Zhangjiagang region, Chang-Zhu-Tan region and Jing-Jin-Tang region, it found that heavy metal contents in most suburb fields were lower than the national 2nd standard of soil quality, but some heavy metal contents were higher than the local background values, which indicated that heavy metals accumulated in suburb fields. Heavy metal contents in vegetable fields were usually higher than paddy and dry fields due to the higher intensive input and use. The study in a special region of Chang-Zhu-Tan showed that it is difficult to reuse the fields after the soil was seriously contaminated. The variation coefficients of soil heavy metals in Jing-Jin-Tang region was higher than Zhangjiagang region.