中文摘要：

采用平衡吸附法，研究了水溶性有机质（DOM）对Cd和Zn在一种碱性土壤表面竞争吸附的影响。结果表明：稻草DOM、污泥DOM、菜叶DOM的存在使Cd和Zn在二元重金属共存体系中的吸附量均降低，其中稻草DOM对重金属吸附的抑制率最高，污泥DOM次之，菜叶DOM的抑制强度最弱，且3种DOM对zn吸附的抑制均强于对Cd吸附的抑制，进而减弱了cd与Zn之间竞争吸附的强度。相对于20％而言，稻草DOM在30~C和40℃时加剧了Zn和Cd在土壤表面竞争吸附的强度。研究结果有助于对多种重金属复合污染土壤的合理评价和有效治理。

英文摘要：

The effect of dissolved organic matter （DOM） on the competitive adsorption between Cd and Zn on an alkaline soil was observed in this study. The examined DOM were extracted from rice straw, sewage sludge and vegetable leaf, respectively. The results showed that the adsorption of Cd and Zn in binary system was inhibited by the presence of all kinds of examined DOM The inhibition by the DOM from rice straw was the strongest while by the DOM from vegetable leaf was the weakest. The inhibitions of all kinds of examined DOM for Zn were greater than that for Cd, which resulted in the decrease of the competitive intensity between Cd and Zn for the adsorption on the soil. However, in the presence of DOM from rice straw, the competitive adsorption between Cd and Zn was more intensive at 30℃ and 40℃ than that at 20℃. These results would facilitate the rational evaluation and effective remediation of polluted soil by multi-heavy metals.