潜流带中反硝化作用是去除硝态氮的主要机制，而碳源则是反硝化过程必不可少的物质之一。为了研究不同碳源的反硝化作用，开展了模拟柱实验，研究潜流带沉积物层中不同碳源(葡萄糖、柠檬酸、腐殖酸及混合碳源)对氮素迁移转化的影响，重点研究了不同含量腐殖酸的影响。结果表明：①混合碳源模拟柱中硝态氮的减少量最多，其次依次为葡萄糖、腐殖酸和柠檬酸；各模拟柱中反硝化作用均强于异化还原作用，说明硝态氮的减少以反硝化作用为主；②腐殖酸含量越高，模拟柱中硝态氮浓度下降越大，随碳源含量的增加，反硝化作用及异化还原作用均增强，但仍以前者为主。%Denitrification is the principal mechanism of nitrogen removal in hyporheic zone and carbon source is one of the es-sential materials in the denitrification process. In order to study the denitrification effect of different carbon sources, simulation column tests of different carbon source categories ( glucose, citric acid, humic acid and their admixture) , with emphasis on dif-ferent content of humic acid, were conducted to analyze the migration and transformation of nitrogen in hyporheic sediments. The result shows that the nitrate reduction in the column of mixed carbon sources is the largest and followed by glucose, humic acid and citric acid;the denitrification is stronger than the dissimilation-deoxidization in all four columns, showing the major role of denitrification effect in nitrate reduction;the higher the concentration of humic acid, the more the nitrate reduction; with incre-ment of carbon source concentration, both denitrification and dissimilation-deoxidization increase, but denitrification still plays a major role.
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