水溶性有机质对土壤吸附有机污染物的影响

Effects of dissolved organic matter on the sorption of organic pollutants to soils

在自然环境中,水溶性有机质(DOM)会对土壤吸附有机污染物产生影响.基于已有的成果,本文综合分析了DOM的有关因素对土壤吸附有机污染物的影响.研究表明,不同来源的DOM的亲疏水组分比例不同;随着腐解时间的增长,亲水组分减小,疏水组分增加.外源DOM的极性与亲疏水组分所含官能团的种类和数量、分子量均会影响有机污染物的吸附;DOM的临界值浓度与土壤有机质含量负相关.当DOM浓度大于临界值时抑制吸附,反之促进吸附.DOM具有酸碱缓冲作用,影响土壤溶液的pH,进而影响对有机污染物的吸附.由于土壤内源DOM对有机污染物具有增溶作用,会抑制土壤吸附有机污染物.论文最后对今后的相关研究方向提出了建议.

In nature environment, dissolved organic matters （DOM） can influence the sorption of organic pollutants to soils. Based on previous studies, the influencing factors of DOM on the sorption of organic pollutants to soils were discussed systematically. It showed that the DOMs of different origins have different proportions of hydrophobic to hydrophilic component. The content of hydrophobic content of DOM increases with decaying time of the materials. There are various possible interaction mechanisms between DOM and organic compounds. The polarity, molecular weight and the type and quantity of functional groups of DOM all can affect the sorption of organic compounds. There is a critical concentration of DOM, which is negatively related to the content of organic matter in the soil. DOM inhibits sorption of organic compounds when DOM concentration is greater than the critical value, otherwise DOM enhances the sorption process. DOM can also affect the organic pollutants sorption process to soils by influencing solution pH values because of DOM pH buffering effect. The endogenous DOM of soil inhibits the sorption of organic compounds on soils. In the end of the review, the prospective research directions were put forward.