摘要
了解重金属复合污染物在土壤-植物系统中的迁移分配情况对污染土壤的安全利用、土壤环境质量标准的修订以及重金属污染土壤的植物修复具有重要意义。通过盆栽试验,以芥菜和油菜为例,研究了铅-锌-镉复合污染物在土壤-植物系统中的迁移分配情况。结果表明:与对照相比,复合污染条件下,芥菜和油菜体内重金属含量显著提高,且Cd含量的提高程度要远远高于Pb和Zn;芥菜和油菜对Cd的吸收达到了100 m g/kg以上,表现出超富集植物的吸收水平。重金属的富集系数大小依次为Cd>Zn>Pb,地下部富集系数要高于地上部,转运系数大小为Cd≈Zn>Pb。Pb、Zn、Cd的富集系数均随各自元素在土壤中含量增大而减小,而且表现为低含量时显著减小,高含量时缓慢减小;重金属在土壤-植物系统的迁移分配深受共存元素的影响,且在不同元素之间和不同浓度范围内表现出不同的特点。Pb、Zn、Cd在芥菜和油菜体中积累量,均与其各自在土壤中的含量成正相关;Zn和Cd对Pb的吸收积累以及Pb对Zn的吸收积累具有明显的抑制作用;Zn-Cd对Zn的吸收积累具有正的交互作用,而对Cd的吸收积累具有负的交互作用。
It is important for the safety use of contaminative soils,the revision of soil environment equality standards and the phytoremediation of contaminative soils to grasp the transfer and distribution of heavy metals in soil-plant systems.Pot experiments were conducted to study the transfer and interaction of Pb,Zn and Cd in the soil-mustard/cole systems.The results showed that： compared with the contrast,the content of Pb,Zn and Cd in mustard and cole was heightened evidently under multi-pollution conditions,and the enhancement of Cd was very bigger than that of Pb and Zn.The accumulation of Cd got up to 100 mg/kg.Bioconcentration factors（BCF） of the three metals in the stem and leaf were bigger than that in the root,and appeared Cd〉Zn〉Pb.Transport factors（TF） of the three metals appeared Cd≈Zn〉Pb.BCF reduced with their respective contents enhanced in the soil,and faster reduced in low content than in high content.Coexistensive elements had prominent effect on BCF and TF,and the effect appeared various characteristics between different elements and in different content ranges.The accumulation of Pb,Zn and Cd was all positive correlation with their respective content in the soil.Zn and Cd restrained the accumulation of Pb,and Pb restrained the accumulation of Zn.Zn-Cd had positive interaction for the accumulation of Zn,and had negative interaction to the accumulation of Cd.
出处
《水土保持学报》
CSCD
北大核心
2007年第6期1-6,共6页
Journal of Soil and Water Conservation
基金
国家自然科学基金资助项目(20577008)
国家"863"计划项目(2005AA219040)
湖南省自然科学基金资助项目(05JJ30017
06JJ50026)
湖南省高校青年骨干教师培养对象资助项目
湘潭市科技计划项目(SF2005-09)
关键词
重金属
复合污染
土壤污染
芥菜
油菜
迁移
交互作用
heavy metals
multi-pollution
soil pollution
mustard
cole
migration
interaction
