以福建泉州水源地山美水库和惠女水库的表层底泥和上覆水为研究对象,室内静态模拟试验研究了生物沸石薄层覆盖削减水源水库氮负荷的效果及可行性,探讨了上覆水体溶解氧(DO)浓度对削减氮负荷的影响,分析了削减氮负荷的作用机理.结果表明,覆盖强度为1 kg/m2的生物沸石覆盖(厚度约1 mm)对上覆水中总氮的削减率为58.89%~65.75%,对底泥中总氮的削减率为10.39%~13.08%,对底泥中铵态氮的削减率为32.35%~44.56%,对底泥中有机氮的削减率为8.41%~11.04%;对于以硝态氮为主要形态氮的上覆水体,DO浓度越低,越有利于高效菌脱氮;可见,生物沸石薄层覆盖能有效削减水源水库氮负荷,利用生物沸石薄层覆盖技术削减水源水库氮负荷是可行的,但需要进一步研究水源水库底泥生物沸石薄层覆盖修复过程中氮的迁移转化机制.%In this study, samples were collected from overlying water and surface sediment in Shanmei Reservoir and Huinü Reser-voir in Quanzhou City, Fujian Province. The efficiency of nitrogen load reduction by thin-layer capping with biozeolite in the source water reservoirs was investigated through a series of laboratory-scale static simulating experiments. The effect of dissolve oxygen con-centration in overlying water on reducing nitrogen load was discussed and the mechanism to reduce nitrogen load by thin-layer cap-ping with biozeolite was also explored. The results showed that the reduction efficiency of total nitrogen in overlying water ranged from 58.89% to 65.75% by thin-layer capping with biozeolite at a dose rate of 1 kg/m2( the thickness of 1 mm) , and the reduction efficiencies of total nitrogen, ammonium nitrogen and organic nitrogen in sediments were in the range of 10.39%-13.08%, 32.35%-44.56% and 8.41%-11.04%, respectively. To overlying water of the main form of nitrate, the lower the dissolve oxygen concentra-tion of overlying water, the better the efficiency of biological denitrogenation by high efficient bacteria. Therefore, thin-layer cap-ping with biozeolite is efficient and feasible to reduce nitrogen load in the source water reservoirs. However, it is urgent to under-stand the mechanisms of nitrogen transportation and transformation in remediation process of sediment using thin-layer capping with biozeolite.
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