土壤中添加蚯蚓及秸秆对油菜积累镉的影响

Effects of adding earthworms and straw into soil on cadmium accumulation in rape

采用盆栽试验,在不同镉(Cd)污染浓度的灰漠土中分别添加蚯蚓和新鲜秸秆,研究了添加蚯蚓和秸秆还田条件下油菜(Brassica rapa L.spp.Chinenesis)-土壤体系中Cd的分布情况。结果发现:(1)添加蚯蚓可有效增加土壤中Cd向油菜体内转移;蚯蚓可以在Cd污染的土壤中生存,蚯蚓体内Cd浓度随土壤环境中Cd的增加而增加。(2)添加不同比例的秸秆,可促进土壤Cd向油菜体内和根际土壤中转移,促进效果为土壤∶秸秆=1∶1>土壤∶秸秆=2∶1>土壤∶秸秆=1∶0;在相同Cd浓度土壤中,油菜中Cd含量>根际土中Cd含量>土壤中的Cd含量,说明施加秸秆可有效促进油菜对Cd的积累。

In pot experiments,earthworms and fresh straw were added into gray desert soil with different concentrations of Cd pollution to study the rape（Brassica rapa L.spp.Chinenesis） Cd accumulation in the soil system under two treatments： earthworm and straw additions.The results showed that：（1） Under different conditions of soil Cd-pollution,the addition of earthworms can effectively promote Cd in the soil to transfer into rape;earthworms can survive in the Cd-contaminated soil,while with the increase of Cd in the environment,Cd concentration in earthworm bodies increase too.（2） In the rape-soil system,addition of different proportions of straw into soil can promote Cd to transfer into rape bodies and rhizosphere soil,and the promotion effects are soil∶straw=1∶1soil∶straw=2∶1soil∶straw=1∶0;in the soil with same Cd concentration,Cd content in rapeCd content in rhizosphere soilCd content in soil,which indicates that application of straw can effectively promote the accumulation of Cd in rape.