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

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.