铬砷及其交互作用对其土壤-植物系统迁移的影响

Influences of Cr-As and Their Interaction on Migration in Soil-Plant System

通过黑麦盆栽试验,研究铬、砷及其交互作用对其土壤-植物系统迁移的影响。结果表明:(1)Cr单独处理中,随着Cr浓度的增大,土样中残余Cr含量随之增大,但残余Cr占外源Cr的比例降低,说明外源Cr会促进土壤中Cr向植物的迁移;(2)交互处理中,随着As水平的提高,同一Cr处理浓度的土壤中Cr残余量增大,即As的加入抑制了土壤中Cr向植物的迁移,且随着As浓度的增大,这种抑制作用越明显;(3)As单独处理中,随着As处理浓度的增大,土样中残余As量也逐渐增大,但土壤中残余的As量大于加入的外源As,植物体内吸收的As受外源As的影响较小;(4)交互处理中,同一As水平下,随着Cr浓度的增大,植物样中As含量变化比较平缓,而且不同As水平下植物体中As含量的变化趋势基本一致,即土壤中As向植物迁移受外源Cr的影响很小。

Pot experiments is are done to research toxicity effects of Cr and As, as well as their interaction and influences on migration in soil-plant system. The results show that： （1） When Cr is treated singly, with the increasing of Cr concentration, the amounts of residual Cr in soil increase, but the proportion of residual Cr to added Cr is decreased. This illustrates that added Cr can promote migration of soil Cr to rye plants. （2） With the heightening of As levels in interaction treatments, the amounts of residual Cr increase in the same treatment. The adding of As can prohibit migration of soil Cr to plants, and with the increasing of As concentration, the prohibition of As is stronger. （3） When As is treated singly, with the increasing of As concentration, the amounts of residual As in soil increase, but the amounts of residual As in soil are greater than added As. As that is assimilated by the plants is influenced slightly by added As. （4） In the process of interaction treatments, at the same As level, with the increasing of Cr concentration, the contents of As in rye plants change equably. The As contents of plants at the different As level change at the same trend. The migration of As in soil to plant is influenced slightly by added Cr.