Cd-Pb复合污染在土壤-水稻系统中生态效应的研究

Ecological Effect of Cd Pb Combined Pollution on Soil-Rice System.

采用盆栽试验研究了重金属复合污染物在土壤 -水稻系统中迁移、积累规律及生态效应。结果表明 :Cd、Pb复合污染使水稻株高比对照的下降了 5～ 7cm ,水稻减产 2 0 % ,2元素交互作用特别是 5元素复合作用影响了水稻的正常生长发育 ;不同处理中重金属在水稻籽实的分配比例依次为 5元素 >2元素 >单元素 ;Cd -Pb 2元素交互作用时 ,Pb元素的存在促进了水稻对Cd元素的吸收 ,而Cd元素却抑制了水稻对Pb元素的吸收 ;Cd比Pb元素易向地上部迁移 。

Pot experiments were conducted to study laws of the migration and accumulation of heavy metals in the soil rice system and their ecological effect on the system. Results show that in treatment Cd Pb the crop was 5～7 cm shorter in plant height and 20% less in yield than that in CK. Normal growth of the crops in treatment Cd Pb and treatment Cd Pb Cu Zn As was seriously affected.In terms of distribution of heavy metals in grains,the treatments were in the order of treatment Cd Pb Cu Zn As>treatment Cd Pb>treatment single element.In treatment Cd Pb the presence of Pb stimulates the plant to absorb Cd,whereas the presence of Cd inhibits the absorption of Pb by rice.Cd is more mobile than Pb and likely to migrate upwards while Pb tends to accumulate in the root of rice.