鄱阳湖湿地重金属形态分布及植物富集研究

Study on the Speciation Distributing and the Plants Enrichment of Heavy Metal in the Wetland of Poyang Lake

研究了鄱阳湖湿地土壤中Cu,Zn,Pb和Cd形态与植物富集的关系.结果表明:鄱阳湖土壤中Cu,Pb和Zn主要以有机态和残渣态为主,水溶态和离子交换态等生物有效性态含量很少;而Cd则主要以水溶态和离子交换态等生物有效性态为主,因此Cd的生态危害较大.相关分析和偏相关分析均显示:植物中重金属含量与其生存环境中重金属水溶态或离子交换态含量直接相关,这与理论上植物只能吸收重金属水溶态相符.植物对重金属的富集能力表现出Zn>Cu>Cd>Pb的趋势.用重金属水溶态或离子交换态进行植物富集研究,更具有可比性和科学性.

The relationship between speciation of heavy metals Cu, Zn, Pb and Cd and plants enrichment was researched. The results showed that the organic matter-sulfide bound and residuum speciation are the main content of Cu, Zn, Pb; the soluble and ion-exchangeable speciation （bioavailable speciation） is the main content of Cd, and so the ecological hazard of Cd is stronger. According to correlation analysis and partial correlation analysis, the content of heavy metals in plants directly correlates with the content of soluble and ion-exchangeable speciation of heavy metals in the existing environment of plants, which fits to the theory that the plants can only absorb the soluble speciation of heavy metals. The enrichment ability of plants in heavy metals is in the order of： Zn 〉 Cu 〉 Cd 〉 Pb. It is more scientific to study plants enrichment by the soluble and ion-exchangeable speciation of heavy metals.