中文摘要：

采集缺氧活性污泥进行室内微生物驯化，培养耐砷反硝化菌。把耐砷反硝化菌、营养液和吸附As（V）的水铁矿在厌氧条件下培养，研究反硝化菌代谢作用下，系统中Fe、Mn、NO3^-和As形态的动态变化。结果表明，缺氧活性污泥中的反硝化菌具有一定的耐砷能力。在砷含量500μg／L以内，其反硝化强度基本不受砷的影响。在吸附有砷的水铁矿体系中，反硝化菌所产生的反硝化作用可导致溶液中NOF含量的降低、Fe含量的升高、As含量降低，且As（III）所占比例增加。这说明，体系中水铁矿的还原性溶解和As（V）的还原性解吸已经发生。As含量降低的原因是，在培养体系中水铁矿的含量高，Fe的释放量只占很小比例，表层水铁矿被还原后，在次表层形成新的水铁矿吸附位，这种新吸附位不仅可以吸附溶液中已经存在的As，而且能够再吸附由于还原性溶解和解吸所释放出的As。

英文摘要：

Anaerobic activated sludge was used to cultivate arsenic-resistant denitrificator in laboratory. The acclimated bacteria were incubated with nutrient solution and As-adsorbing ferrihydrite in anaerobic condition to investigate the geochemical behavior of As adsorbed on ferrihydrite. The concentrations of Fe, Mn, NO3^-and As species in suspensions were monitored during the incubation. The acclimation results show that the denitrificator in the anaerobic activated sludge can abide the As（V）in the solution, and its denitrification intensity was less affected by As when its concentration is less than 500μg/L. In the batch incubation with addition of As-adsorbing ferrihydrite, the presence of arsenic-resistant denitrificator caused an increase in concentrations of Fe and Mn, a decrease in concentrations of NO3^- and As, and a high ratio of As（III） to the total As. This indicates that both the reductive dissolution of ferrihydrite and the reductive desorption of As（V） occurred in the batches incubated with arsenic-resistant denitrificator and As-adsorbing ferrihydrite. The decrease in As concentration was caused by the readsorption of the released As on the new adsorption sites of the partially dissolved ferrihydrite because of high ratio of ferrihydrite to the solution.