Abstract A lab-scale anaerobic ammonium oxidation (anammox) biofilm reactor was operated to explore the impact of free ammonia (FA) and free nitrous acid (FNA) on the anammox process with nitrogen loading rate (NLR) increasing from 0.1 to 0.5 g/L.d with identical pH of 7.8. When influent NLR was less than 0.4 g/L.d, total inorganic nitrogen (TIN) removal efficiency maintained around 80% on average. When the NLR increased to 0.5 g/L.d, TIN removal efficiency sharply reduced to 66%. It was revealed that Candidatus Brocadia and Candidatus Kuenenia were the main anammox genera in this study. When NLR raised from 0.1 to 0.5 g/L.d, together with FA from 4.44 to 20.23 mg/L and FNA from 5.00 to 22.69 μg/L, the dominant anammox genus showed a shift from Candidatus Kuenenia to Candidatus Brocadia. The highest anammox community abundance of 25.3% and maximum absolute abundances of anammox-related functional genes were observed at NLR of 0.3 g/L.d, together with 12.88 mg/L FA and 14.58 μg/L FNA.

中文翻译：

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微生物群落转移和功能基因响应厌氧氨氧化生物膜反应器中氮负荷变化

摘要 运行实验室规模的厌氧氨氧化（anammox）生物膜反应器，探索游离氨（FA）和游离亚硝酸（FNA）对厌氧氨氧化过程的影响，氮负载率（NLR）从0.1增加到0.5 g/ Ld 具有相同的 pH 值 7.8。当进水NLR小于0.4 g/Ld时，总无机氮（TIN）去除率平均保持在80%左右。当 NLR 增加到 0.5 g/Ld 时，TIN 去除效率急剧下降到 66%。结果表明，Candidatus Brocadia 和 Candidatus Kuenenia 是本研究中的主要厌氧菌属。当 NLR 从 0.1 升至 0.5 g/Ld，FA 从 4.44 升至 20.23 mg/L 和 FNA 从 5.00 升至 22.69 μg/L 时，优势厌氧氨氧化菌属显示从 Candidatus Kuenenia 向 Candidatus Brocadia 转变。最高的厌氧氨氧化群落丰度为 25。