摘要
土壤环境微界面是土壤组分(矿物和有机质)、植物根系、微生物等微界面的集合体和动态变化的连续体.土壤胶体微界面可理解为土壤固/液界面的双电层结构.这些动态变化的异质微界面,按其表面结构特点可分为硅氧烷型表面、水合氧化物型表面和有机物表面.环境污染物在土壤胶体微界面的迁移转化是污染物在土壤固-液界面反应的动态平衡过程,包括吸附/解吸、沉淀/溶解、络合/螯合、氧化/还原等反应.植物根际是植物与土壤组分和微生物相互作用的活跃区域,根际微界面决定着污染物向植物根系的运输、植物吸收及转运,为污染物经土壤向食物链传递的主要通道.根际微生物在重金属离子的吸附和氧化、还原、转化,以及有机污染物的降解和转化中起重要作用.这些异质微界面相互关联、相互作用,在土壤环境中构成微界面的连续体,决定着污染物在土壤环境中的赋存形态、生物有效性和向其它环境介质(如水体和植物)的迁移,因而在土壤污染控制和污染土壤修复中具有特别重要的意义.土壤环境微界面过程的研究已成为环境科学的研究前沿,值得引起土壤环境科学工作者的重视,并进行系统而深入的研究.
Soil environmental micro-interfaces are of a collection and a continuum of surfaces of soil clay minerals, oxides, organic matters, plant roots and microbes. The soil colloidal interfaces could be simply described as a diffuse electrical double-layer structure on the interface of soil particles and solutions. These heterogeneous micro-interfaces can be divided into three types based on their surface structure characterizations： siloxane, hydrous oxide and organic matter surfaces. The transport, transformation and degradation of pollutants in the soil are dynamic processes, including a series of reactions of sorption/ desorption, precipitation/ dissolution, complexation/ chelation, and oxidation/ reduction. Rhizosphere interface is the most active area in soil-plant ecosystems with intensive interactions among soil particles, organic compounds, plant roots and microorganisms. It is the channel of pollutant transporting to plants and linking with food chain. Microbial interface plays important roles not only in sorption and redox reactions of heavy metals, but also degradation and transformation of organic pollutants. As a dynamic continuum, different soil heterogeneous micro-interfaces interact with each other and control the forms, bioavailability, toxicity and transport of pollutants in soil-plant ecosystems. Therefore, they are of significance in soil pollution control and soil remediation, and deserve intensive investigations.
出处
《环境科学学报》
CAS
CSCD
北大核心
2009年第1期21-27,共7页
Acta Scientiae Circumstantiae
基金
国家创新研究群体科学基金(No.50621804)
国家自然科学基金项目(No.40571082)~~
关键词
环境微界面
土壤胶体
根际
微生物
污染物
反应过程
污染控制
environmental micro-interface
soil colloid
rhizosphere
microorganism
pollutants
reaction mechanism
pollution control
