贵州北部菜地土壤镉含量与蔬菜镉污染的关系

以贵州省遵义县为研究区域,采用污染指数法对菜地土壤镉污染状况进行分析和评价,对不同种类蔬菜中镉的富集系数进行层级聚类分析。结果表明,土壤平均镉含量0.356 mg/kg,超标率达72.6%。研究区镉污染指数为1.19,总体属轻度污染。不同种类蔬菜镉含量高低顺序为:辣椒>西红柿>白菜>菠菜>茄子>黄瓜>豇豆>四季豆。不同种类蔬菜富集镉的能力不一,辣椒和西红柿富集能力较强,富集系数分别为0.118和0.107。辣椒、西红柿和白菜的富集系数与土壤镉含量呈显著正相关关系,特别以菠菜的富集系数与土壤镉含量呈极显著正相关关系。

On the Relation of Cadmium Concentration in Vegetable Soil to Cadmium Contamination in Vegetables of Northern Guizhou

Taking Zunyi county in Guizhou province as example,this study analyzed and assessed the pollution of heavy metal Cd in vegetable soil with pollution index,and the concentration index of Cd in different varieties of vegetables with hierarchical cluster.The results showed that the average content of Cd in soil was 0.356 mg/kg,exceeding the set standard 72.6%.The average single pollution index of the investigated area was 1.19,showing low-grade contamination.The sequence of Cd content in different vegetables was: chili>tomato>cabbage>spinage>eggplant>cucumber>cowpea>kidney bean.The concentration of Cd was different in varieties of vegetables,among which the chili and tomato had higher concentration,with the concentration index 0.118 and 0.107 respectively.The Cd content in chili,tomato and cabbage showed a significantly positive correlation with the Cd content in the soils,spinage showing a most significantly positive correlation.