| 摘要: |
| 【目的】探讨硅对外源镉、锌复合污染条件下玉米植株体内镉、锌含量及土壤中不同形态锌、镉含量的影响。【方法】以玉米为供试作物，采用盆栽试验在土壤中施用不同水平硅、锌、镉，其中硅的施用水平分别为0，4 mg/kg，锌施用水平分别为0，300，700 mg/kg，镉施用水平分别为0，3，10 mg/kg，进行完全组合试验设计，共计18个处理，每处理重复3次，于玉米种植后60 d时取样，测定镉锌复合污染条件下玉米根、茎叶中镉、锌含量以及土壤中可交换态、碳酸盐结合态、铁锰氧化物结合态、有机结合态、残渣态锌、镉含量。【结果】在单一镉处理条件下，随着镉含量的增加，玉米根和茎叶中镉含量显著增加，加入硅能显著降低玉米幼苗体内镉含量。在镉锌复合污染条件下，镉含量及硅含量均相同的处理，玉米根和茎叶中镉含量随锌含量的增加而降低，且施入锌的量越大，玉米体内镉含量越低。在镉锌复合污染条件下，镉含量及锌含量均相同的处理，玉米根和茎叶中镉含量随硅的加入而降低，差异达显著或极显著水平。在单一锌污染条件下，随着锌施入量的增加，玉米根、茎叶中锌含量增大，但加入硅会显著降低玉米根、茎叶中的锌含量。在镉锌复合污染条件下，当锌含量相同时，玉米根、茎叶中锌的含量随着镉或硅含量的增加而降低。在镉、锌复合污染条件下，加硅或锌，都能降低土壤中交换态和有机态镉含量，而增加铁锰氧化态、碳酸盐结合态以及残渣态镉含量；加硅或镉，均能降低土壤中交换态和有机态锌含量，而增大铁锰氧化态、碳酸盐结合态以及残渣态锌含量。【结论】硅能显著降低玉米体内重金属含量，减少重金属向玉米植株地上部的迁移。 |
| 关键词: 硅 镉 锌 复合污染 |
| DOI： |
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| 基金项目:“十二五”渤海粮仓科技示范工程辽河三角洲项目 |
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| Impacts of Si on concentrations of Cd and Zn in corn and their forms in soil |
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TONG Qian,JI Weiwei,SHEN Yang,et al
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| Abstract: |
| 【Objective】The contents of cadmium (Cd) and zinc (Zn) in maize under compound pollution of Cd and Zn and their forms in soil were discussed.【Method】 Corn was planted in pot under 18 treatments with different levels of Si (0,4 mg/kg),Zn (0,300,and 700 mg/kg),and Cd (3,3 and 10 mg) in soil.After 60 days,samples were collected for determination of Cd and Zn contents in root and stem of corn,and changes in exchangeable,carbonate,iron and manganese oxide bounded,organic bounded and residual Zn and Cd in soil.【Result】Under single Cd treatment,the contents of Cd in maize root,stem and leaf increased significantly with the increase of Cd.Adding Si significantly decreased Cd contents.Under Cd and Zn compound pollution and same Cd and Si contents,Cd contents in maize decreased with the increase of Zn.When Cd and Zn contents were fixed,Cd contents in maize decreased significantly or extremely significantly with the addition of Si.Under single Zn pollution,Zn content increased with the increase of Zn in soil,but Zn contents decreased significantly with the addition of Si.Under Cd and Zn compound pollution,Zn contents in corn decreased with the increase of Cd and Si.Under Cd and Zn compound pollution,contents of exchangeable and organic Cd in soil decreased while oxidation state,carbonate bounded and residual Zn increased with the increase of Si and Zn.【Conclusion】Si can significantly reduce the contents of heavy metals in maize,and reduce the migration of heavy metals to aboveground parts. |
| Key words: Silicon Cadmium Zinc Compound pollution |
