重金属在土壤生态系统中的富集及毒性效应

对清水塘重金属污染区土壤生态系统重金属的富集及毒性效应的研究结果表明，土壤中 主要富集的重金属元素为生物毒性较强的Cd、Hg、As以及具有一定毒性的Zn、Pb、Cu，平均综 合污染指数为640.大型土壤动物重金属含量的分析结果表明，重金属富集量随污染程度的 增加而增加，尤其某些巨蚓科种类对Cd表现高富集，富集系数为1196.通过染毒试验进一 步证明，土壤动物种类和数量随Cd浓度的增加而减少.同工酶分析表明，Cd对蚯蚓同工酶活性 有明显的毒性效应.污染区主要种植蔬菜作物，而重金属在蔬菜体内的富集量也随污染 程度的增加而增加，其中蔬菜对Cd的富集有明显的品种间差异.

Enrichment and toxicity effect of heavy metals in soil ecosystem

The study on the heavy metals-polluted soil of Qingshuitang District,Zhuzhou City showed that the main enriched heavy metals in the soil were Cd,Hg,As,Zn,Pb and Cu,among which,the former three had strong biotoxicity while the others had definite toxicity,with the average integrative pollution index being 6.40.The heavy metals enrichment in soil animals increased with increasing pollution degree.Especially for some species of Megascoiecidae,they had a high enrichment of Cd,with the enrichment index being 11.96.The species and quantity of soil animals decreased with increasing Cd concentration.Cd had an obvious biotoxic effect on Megsacoiecidae's isozyme activity.The heavy metals enrichment in vegetables also increased with increasing pollution degree,but there existed obvious interspecies difference in Cd enrichment.