The decline of sewage purification efficiency in winter is a frequent problem in sub-plateau municipal sewage treatment plants (MSTPs). Understanding the links between activated sludge (AS) bacterial community and sewage purification is crucial for exploring the cause of this problem. In this study, Illumina high-throughput sequencing technology was applied to investigate the seasonal changes of AS bacterial community in sub-plateau MSTPs. The sequencing result indicates that the bacterial community OTU number, diversity, and relative abundance in winter are significantly lower than that in summer samples. The discriminant linear effect size analysis (LEfSe) reveals that Proteobacteria and Chloroflexi members were enriched in summer AS, while Actinobacteria and Firmicutes were enriched in winter AS. The results indicate that different core bacterial community assembly was developed in summer and winter, respectively. The changes in bacterial community may be the reasons for the lower sewage purification efficiency in winter. Furthermore, redundancy analysis (RDA) shows that temperature and dissolved oxygen (DO) are the principal factors that drive the seasonal changes in the core bacterial community diversity, richness and structure in sub-plateau MSTPs. Thus, the sub-plateau AS selects for a unique community assembly pattern and shapes the particular AS ecosystem. These results expand previous understanding and provide insight into the relationship between bacterial community and performance of sub-plateau MSTPs.

中文翻译：

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核心细菌群落的季节变化决定了亚高原市政污水处理厂的污水净化。

冬季污水净化效率的下降是高原地区市政污水处理厂（MSTP）经常遇到的问题。了解活性污泥（AS）细菌群落与污水净化之间的联系对于探索此问题的原因至关重要。在这项研究中，Illumina高通量测序技术被用于调查亚高原MSTP中AS细菌群落的季节性变化。测序结果表明，冬季细菌群落的OTU数量，多样性和相对丰度明显低于夏季样品。判别线性效应大小分析（LEfSe）表明，夏季AS中富集了变形杆菌和绿藻，而冬季AS中富集了放线菌和Firmicutes。结果表明，分别在夏季和冬季开发了不同的核心细菌群落组装。细菌群落的变化可能是冬季污水净化效率较低的原因。此外，冗余分析（RDA）显示温度和溶解氧（DO）是驱动亚高原MSTPs核心细菌群落多样性，丰富性和结构的季节性变化的主要因素。因此，亚高原自治区选择独特的社区聚集模式并塑造特定的自治区生态系统。这些结果扩大了以前的理解，并提供了对细菌群落和亚高原MSTPs性能之间关系的深入了解。细菌群落的变化可能是冬季污水净化效率较低的原因。此外，冗余分析（RDA）显示温度和溶解氧（DO）是驱动亚高原MSTPs核心细菌群落多样性，丰富性和结构的季节性变化的主要因素。因此，亚高原自治区选择独特的社区聚集模式并塑造特定的自治区生态系统。这些结果扩大了以前的理解，并提供了对细菌群落和亚高原MSTPs性能之间关系的深入了解。细菌群落的变化可能是冬季污水净化效率较低的原因。此外，冗余分析（RDA）显示温度和溶解氧（DO）是驱动亚高原MSTPs核心细菌群落多样性，丰富性和结构的季节性变化的主要因素。因此，亚高原自治区选择独特的社区聚集模式并塑造特定的自治区生态系统。这些结果扩大了以前的理解，并提供了对细菌群落和亚高原MSTPs性能之间关系的深入了解。亚高原MSTPs的丰富度和结构。因此，亚高原自治区选择独特的社区聚集模式并塑造特定的自治区生态系统。这些结果扩大了以前的理解，并提供了对细菌群落和亚高原MSTPs性能之间关系的深入了解。亚高原MSTPs的丰富度和结构。因此，亚高原自治区选择独特的社区聚集模式并塑造特定的自治区生态系统。这些结果扩大了以前的理解，并提供了对细菌群落和亚高原MSTPs性能之间关系的深入了解。