湿地植物根表铁膜研究进展  

Iron plaques on wetland plant root surface:A review.

作　　者：姚海兴[1] 叶志鸿[1] 

机构地区：[1]中山大学生命科学学院有害生物控制与资源利用国家重点实验室,广州510006

出　　处：《生态学杂志》2009年第11期2374-2380,共7页Chinese Journal of Ecology

基　　金：教育部高等学校博士点基金项目(20558097);广东省自然科学基金资助项目(07003650)

摘　　要：湿地植物具有一系列生理和结构上适应浸水环境的特征,如根系的通气组织和渗氧能力,这使得植物根际微环境处于氧化状态,这样土壤中的铁和锰会在植物根表被氧化而形成红棕色的铁锰氧化物胶膜。土壤中的铁锰元素和局部的氧化环境是铁膜形成的2个重要条件。铁膜的主要组分为铁锰的氧化物及其水合物,它是一种两性胶体,可以通过离子之间的吸附-解吸、氧化-还原、有机-无机的络合等作用改变根际环境中重金属阳离子和养分的存在形态,从而影响这些离子的生物有效性,进而能影响土壤-湿地植被体系中污染物和养分的迁移。本文主要综述了湿地植物根系铁锰氧化物胶膜的形成、组成以及对植物吸收外部介质中的重金属和养分的影响,并提出了在今后的研究中仍值得进一步探讨和解决的问题。Wetland plants have a series of physiological and anatomical characteristics to adapt flooding habitat, e. g. , their root aerenchyma and oxygen-penetrating capability can make the rhizospheric micro-environment be under oxidation condition, resulting in the formation of Fe/Mn plaques on root surface. Soil Fe and Mn and thee micro-environment oxidation condition are the two important prerequisites for the formation of the Fe/Mn plaques. The plaques are mainly composed of Fe- and Mn-oxides and their hydrates, which can alter the forms of heavy metals and nutrients in rhizospherie micro-environment via the actions absorption-desorption, oxidation-reduction, and organic-inorganic chelation, etc. , and thereby, affect the bioavailability and the migration of pollutants and nutrients in wetland soil-plant system. This paper reviewed the researches about the formation and composition of Fe/Mn plaques on wetland plant root surface, and the effects of the plaques on the heavy metals and nutrients uptake by wetland plants. Some problems worthy to be further approached were discussed.

关 键 词：湿地植物 铁膜 重金属 养分富集 

分 类 号：Q948[生物学—植物学]