Abstract: In order to investigate the treatment efficiency of ammonia nitrogen and nitrite nitrogen by different pH values and filter material, we collected nitrifying bacteria in the intensive recirculating aquaculture system as the research object to study the effects of ammonia elimination of six pH gradient (pH 5.0-10.0) and four filter material (ceramic ring, corallite, biofilters brush, biology-ball). When the pH was 8.0-9.0, the removal rate of ammonia nitrogen was 99.86% and 98.95% respectively, which was high than pH 6.0（66.18%）, pH 7.0（71.43%）and pH 10.0（70.51%）. The increase of nitrite nitrogen was less than the decline of ammonia nitrogen when pH was 7.0-9.0, and the great difference appeared at pH 9.0. In the filter material experiment, we found that the removal rate reaching 100% of ammonia nitrogen by biofilters brush, ceramic ring, corallite and biology-ball was on day 3, 4, 6, 7 respectively. The concentration of nitrite nitrogen of ceramic ring and corallite had gradually declined when they reached their highest level 9.60 mg/L and 10.00 mg/L respectively. The concentration of nitrite nitrogen of biofilters brush and biology-ball was maintain a high level when they reached their highest level 9.55 mg/L and 11.00mg/L respectively. The results show that nitrifying bacteria are suitable for alkaline condition(pH 8.0-9.0), especially at pH 9.0. Different filtration materials have different effects on ammonia nitrogen and nitrite nitrogen. Ceramic ring has the better removal rate of ammonia nitrogen and nitrite nitrogen than the other filter material. Biofilters brush only has a good removal effect on ammonia nitrogen. Corallite only has a good removal effect on nitrite nitrogen. Various filter material use would improve the treatment effect of the nitrifying bacteria.

Key words: nitrifying bacteria, pH, filter material, ammonia nitrogen, recirculation aquaculture

摘要： 为了解在不同pH和滤料条件下硝化细菌对氨氮（NH4+-N）和亚硝酸盐氮（NO2--N）的去除效果，通过试验，探讨了5.0~10.0等6个pH梯度以及陶环、珊瑚石、生物刷和生物球等4种滤料的消氨效果。在pH 8.0~9.0时，至试验第7天氨氮去除率分别达99.86%、98.95%，明显高于pH 6.0、7.0和10.0（去除率分别为66.18%、71.43%和70.51%）组。在pH 7.0~9.0时，亚硝酸盐氮浓度的增加小于氨氮浓度的下降，特别是在pH 9.0时两者浓度变化差异明显。生物刷、陶环、珊瑚石和生物球分别在试验的第3、4、6、7天，氨氮去除率达100%。陶环组和珊瑚石组，亚硝酸盐氮浓度在达到最高值（9.60 mg/L和10.00 mg/L）之后开始逐步下降；生物刷组和生物球组在达到最高值（9.55 mg/L和11.00 mg/L）之后基本维持不变。结果表明，硝化细菌适宜碱性的环境条件（pH 8.0~9.0），水体pH 9.0最有利于硝化细菌对氨氮和亚硝酸盐氮的去除。不同滤料对硝化细菌去除氨氮和亚硝酸盐氮有不同的影响。陶环对硝化细菌去除氨氮和亚硝酸盐氮都有良好效果，生物刷只对去除氨氮有良好效果，珊瑚石只对去除亚硝酸盐氮有良好效果。多种滤料配合使用有利于产生优势互补的效果。

关键词: 硝化细菌, pH, 滤料, 氨氮, 工厂化循环水养殖