腐植酸与土壤中重金属离子的作用机理研究概况

在分析我国农田土壤重金属污染状况的基础上,阐述了腐植酸与铬、镉、锌等金属离子在土壤中的作用机理研究现状,认为通过范德华力、氢键、静电吸附、阳离子键桥等形成土壤有机-无机复合体,使腐植质的胶团被吸附在土壤颗粒表面,使带正电的金属离子更牢固地与土壤结合,从而有效防止被农作物吸收。文章指出,腐植物质的结构及其与金属离子作用机理的研究,对于促进腐植酸土壤环境保护领域的应用与相关的技术开发具有重要意义。

General Situation of the Reaction Mechanisms of Humic Substances with Heavy Metal Ions in Soil

On the basis of analyzing the exact contamination situation of agricultural soils in China, the utilization of humic substances to prevent heavy metal contamination from wastewater irrigation is reviewed while the reaction mechanisms of humic substances with heavy metal ions, such as Cr, Cd and Zn, are supposed including formation of organic-inorganic complexes by hydrogen bonds, static electrical adsorption and cation bond etc. As a result, colloidal structural groups of humic substances are adsorbed on the soil surfaces in addition to adsorb metal cations to promote them binding effi ciency. Finally, the heavy metals that retain in the soil matrix can be prevented crops from absorption. Furthermore, the investigations on the reaction of humic substances with metal ions play an important role in environ-mental protection and the relative technical development.