螯合剂对铀镉污染土壤中蚕豆幼苗生理特性影响

The Physiological Characteristics of Vicia faba Linn.to Extract Uranium Cadmium Under Chelate Treatment

通过盆栽试验研究了在不同浓度EDTA、柠檬酸、草酸3种螯合剂作用下不同浓度铀镉复合污染(分别用W1、W2表示)对土壤中蚕豆(ViciafabaL.)幼苗体内叶绿素、丙二醛和细胞质膜透性的影响。结果表明,在所设的两个土壤污染浓度下,较高土壤污染浓度(W2)中植物受损伤程度高于较低土壤污染浓度(W1)中的植物受损伤程度,由此得出较高土壤污染浓度可能更有利于蚕豆对铀镉的吸收;蚕豆的整个生长过程中,对于叶绿素而言,在污染土壤中添加5mg.kg-1的草酸,对其含量影响最大,可能有利于促进蚕豆对土壤中铀和镉的吸收,添加2.5mg.kg-1的柠檬酸次之;对于丙二醛,向污染土壤中添加10mg.kg-1的草酸,对其含量影响最大,可能有利于蚕豆对土壤中铀和镉的吸收,添加2.5mg.kg-1的柠檬酸次之;在细胞质膜透性上,向土壤中添加5mg.kg-1草酸,对其含量影响最大,可能更有利于促进蚕豆吸收土壤中的铀和镉,而添加5mg.kg-1的柠檬酸次之。而EDTA在整个试验中都表现出了对植物较大的生物毒性。

A pot experiment was studied by the effect of the chlorophyll,cell membrane permeability and malondialdehyde of the broad bean（Vicia faba Linn.） seedlings extraction of uranium cadmium pollution（set two concentrations of W1,W2 indicated） under the treatment with the EDTA,citric acid,oxalic acid.The results showed that the overall growth in the broad bean,the high concentration of contaminated soil（W2） was more conducive to uptake the pollutants of uranium and cadmium than the lower the concentration of contaminated soil（W1）to the bean;When added the 5 mg·kg-1 of the oxalic acid to the soil,the influence of the chlorophyll in plants was the greatest,the concentration might be more conducive to absorb the uranium and cadmium of the contaminated soil to the beans,followed by 2.5 mg·kg-1 of the citric acid;When added the 10 mg·kg-1 of the oxalic acid to the soil,the influence of the malondialdehyde in plants was the greatest,the concentration may be more conducive to absorb the uranium and cadmium of the contaminated soil to the beans,followed by 2.5 mg·kg-1 of the citric acid;When added the 5 mg·kg-1 of the oxalic acid to the soil,the influence of the cell membrane permeability in plants was the greatest,the concentration might be more conducive to absorb the uranium and cadmium of the contaminated soil to the beans,followed by 5 mg·kg-1 of the citric acid;In the whole experiment,EDTA had shown greater toxicity to plants.