重金属污染土壤的植物修复及其机理研究

近年来,作为一种成本低廉、对环境友好的修复方法,重金属污染土壤的植物修复成为环境修复领域的研究热点.早期的研究侧重于超富集植物的发现与实际应用,近来超富集植物重金属富集机理的研究得到了重视.尽管重金属植物累积的生化机制尚未能被完整阐述,但在土壤重金属生物活性、超富集植物重金属的吸收、转运、储存等方面还是取得了大量进展.综述了近年来国内外相关研究工作成果,探讨了该研究领域存在的主要问题,认为在有机鳌合剂如有机酸与氨基酸等对重金属活性、耐性和离子迁移转运系统中所起作用等方面尚需要深入研究.如果在植物重金属吸收、迁移、解毒机理及其影响因素等重金属富集的关键方面能取得进展,则将大大丰富污染土壤重金属修复的研究与应用领域.

Phytoremediation of Heavy Metal Contaminated Soil and its Mechanism

Phytoremediation is being developed in recent years as a cost_effective and environmental friendly solution for heavy metal contaminated soils. After an initial focus on plants with an immediate promise of application, research is now being directed at understanding the underlying mechanisms involved in heavy metal hyperaccumulation in plants. In recent years, major scientific progress has been made in understanding the mechanisms of soil heavy metal bioavailability and heavy metal uptake and transport by hyperaccumulators even biochemical basis of the capacity for metal accumulation has not been clearly elucidated. So further studies on both the role of organic acids and amino acids in the heavy metal tolerance mechanism and ion transport systems are clearly required for understanding the phenomenon of metal hyperaccumulation and tolerance. Once the rate_limiting steps for uptake, translocation, sequestration and detoxification of metals in hyperaccumulator plants are identified, an improved understanding of the mechanisms underlying hyperaccumulation of heavy metals should open up new possibilities for the application of metal accumulating plants in the phytoremediation of contaminated soil.