干旱区绿洲土壤Cd-Zn复合污染对胡萝卜的影响及富集迁移规律

以干旱区绿洲土壤为供试材料,通过盆栽实验探讨了Cd-Zn复合污染条件下,土壤重金属的形态变化及其在胡萝卜中的分布、累积和迁移情况.结果表明:随着重金属Cd-Zn复合胁迫质量分数的增加,低质量分数的Cd-Zn胁迫促进了胡萝卜的生长,高质量分数时明显抑制了胡萝卜的生长;Zn的碳酸盐结合态促进了胡萝卜对Zn的累积;胡萝卜对Cd,Zn的富集系数和转运系数及富集量系数和转运量系数的关系均为Cd>Zn,胡萝卜对重金属的迁移能力为Cd>Zn;胡萝卜对Cd,Zn的积累量与土壤中Cd,Zn胁迫量之间呈现多元非线性关系,Cd,Zn的交互作用因质量分数而异.

Effects of Cd-Zn combined pollution on the growth of carrot in oasis soils of arid areas and the migration and enrichment of Cd and Zn

A simulated test of compound contamination by Cd and Zn was carried out for oasis soils.In order to study the compound effects of Cd-Zn,the migration,accumulation and distribution of Cd and Zn in carrots were also studied.The results indicated that lower concentrations of Cd and Zn could promote carrot growth,but a higher concentrations could obviously inhibit carrot growth.CAB-bound Zn made the greatest contribution to Zn accumulation in carrot leaves and roots;the relation of absorption coefficients with transformation coefficients of carrots to Cd and Zn was equally Cd>Zn.What is more,absorption capacity coefficients and transformation capacity coefficients produced the same results.The bio-concentration factors of Cd in carrot leaves and roots were all greater than those of Zn,which showed that the uptake capability of Cd in the carrots was greater than Zn;Cd and Zn accumulation in carrots and Cd,Zn stress in the soil showed a multiple non-linear relationship; Cd and Zn concentrations varied due to the interaction.