This study investigates the performance, resilience and microbial community dynamics of two anaerobic processes, i.e. pure anammox (R1) and partial denitrification/anammox (PD/A) (R2), following a 30-day starvation period. The tolerance to starvation was assessed by comparing nitrogen removal efficiency and microbial activity across both reactors. Results show that the PD/A process recovery to pre-starvation performance levels within just one day, as compared to the pure anammox process. Notably, although the activity of anammox bacteria decreased in both processes during starvation, the decay rate in R1 was 69.59 % higher than in R2, potentially explaining the quicker recovery of R2. Furthermore, enhanced secretion of extracellular polymeric substance (EPS) during starvation served as a protective mechanism. The potential functions and genes in microorganisms, as well as the pathway of nitrogen cycling, were demonstrated through analyses using the KEGG database. This research reveals essential mechanistic insights and strategic guidance for the effective implementation of anammox-based biological nitrogen removal processes.

中文翻译：

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基于厌氧氨氧化的生物反应器中的饥饿恢复力：部分反硝化/厌氧氨氧化 （PD/A） 的稳定脱氮路线


本研究调查了两种厌氧过程的性能、弹性和微生物群落动态，即纯厌氧氨氧化 （R1） 和部分反硝化/厌氧氨氧化 （PD/A） （R2），在 30 天的饥饿期后。通过比较两个反应器的脱氮效率和微生物活性来评估对饥饿的耐受性。结果表明，与纯厌氧氨氧化工艺相比，PD/A 工艺在短短一天内恢复到饥饿前的性能水平。值得注意的是，尽管在饥饿期间这两个过程中厌氨氧化细菌的活性都降低了，但 R1 的腐烂率比 R2 高 69.59%，这可能解释了 R2 恢复得更快。此外，饥饿期间细胞外聚合物物质 （EPS） 分泌的增加起到了保护机制的作用。通过使用 KEGG 数据库的分析，证明了微生物中的潜在功能和基因，以及氮循环的途径。这项研究揭示了有效实施基于厌氧氨氧化的生物脱氮过程的重要机制见解和战略指导。