施用络合剂对印度芥菜吸收土壤中铅的影响

目的]为Pb污染土壤的植物修复提供理论依据。方法]通过在土壤中施加EDTA、柠檬酸、草酸和苹果酸,研究施用络合剂对印度芥菜吸收土壤中Pb的影响。结果]土壤中施加络合剂对印度芥菜的生物量没有明显影响。添加EDTA明显提高了印度芥菜地上部对Pb的吸收,地上部Pb含量达到349 mg/kg,而其他有机酸处理对印度芥菜地上部Pb含量的影响不大。施加EDTA明显提高了Pb向印度芥菜地上部的迁移能力,迁移系数为0.73;施加苹果酸和柠檬酸对Pb的迁移起到了一定的促进作用,但效果不如EDTA明显;施加草酸阻碍了Pb向印度芥菜地上部的迁移。结论]土壤中施加络合剂可提高印度芥菜地上部对Pb的吸收,施用EDTA的效果较好。

Effect of Applying Complexing Agents on Indian Mustard Absorbing Pb in Soil

Objective] The aim was to provide the theoretical basis for phytoremediation in Pb contaminated soil.Method] The effect of applying complexing agents on Indian mustard absorbing Pb in soil was studied by applying EDTA,citric acid,oxalic acid and malic acid in soil.Result] Applying complexing agents in soil had no obvious effect on Indian mustard biomass.Applying EDTA increased the absorption of the above-ground part of Indian mustard to Pb obviously and the Pb content of its above-ground part reached 349 mg/kg,while the treatments of other organic acids had little effect on the Pb content in above-ground part of Indian mustard.Applying EDTA increased the migration ability of Pb toward the above-ground part of Indian mustard obviously with the migration coefficient of 0.73;Applying malic acid and citric acid had promotion effect on Pb migration,but the effect was not so obvious as that of EDTA;Applying oxalic acid inhibited the Pb migration toward the above-ground part of Indian mustard.Conclusion] Applying complexing agents in soil could increase the absorption of the above-ground part of Indian mustard to Pb and the effect of applying EDTA was better.