Study on the Composition and Diversity of Bacterial Communities in a Non-Powered Rural Domestic Wastewater Treatment System

无动力污水处理装置对小水量的农村污水处理具有广阔的发展前景，而栖息其中的微生物的种类和结构决定着污水处理效果。为研究无动力农村生活污水处理装置中微生物分布格局，在不同的时间分别采集装置上层(距进水口0.3 m)和下层(距底部0.1 m)的样品，采用高通量测序技术分析样品中微生物的群落结构，并采样统计分析方法对数据进行处理。结果表明，无动力装置对污水中的CODCr、NH3-N、TN、TP去除率分别为76.63%、82.56%、39.95%、17.41%，无动力农村生活污水装置中主要的细菌门为变形菌门(Proteobacteria)、放线菌门(Actinobacteriota)、厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes)、绿弯菌门(Chloroflexi)、酸杆菌门(Acidobacteriota)，其中，变形菌门(Proteobacteria)和拟杆菌门(Bacteroidetes)对污水脱氮除磷起主要作用，其相对丰度分别为27.50%~90.96%和0.30%~15.95%。属水平上，除S1和X1外，其余水体中优势菌为norank_f__Rhodanobacteraceae、Castellaniella、红细菌属(Rhodanobacter)、Acidocella及分枝杆菌属(Mycobacterium)。其中第二次下层样品中(X2)微生物组成简单，主要由变形菌门(Proteobacteria)、放线菌门(Actinobacteriota)组成。综上，无动力污水处理装置中微生物种类丰富，有利于农村生活污水的处置。The non-powered wastewater treatment device holds broad development prospects for small-scale rural wastewater treatment, and the types and structure of microorganisms inhabiting it determine the treatment efficiency. To investigate the microbial distribution patterns in non-powered rural domestic wastewater treatment systems, samples were collected from the upper layer (0.3 m from the inlet) and lower layer (0.1 m from the bottom) of the device at different time points. High-throughput sequencing technology was employed to analyze the microbial community structure in the samples, followed by statistical analysis methods to process the experimental data. The experimental results demonstrate that the non-powered system achieved removal efficiencies of 76.63% for CODCr, 82.56% for NH3-N, 39.95% for TN, and 17.41% for TP in wastewater treatment. Microbial community analysis identified Proteobacteria, Actinobacteriota, Firmicutes, Bacteroidetes, Chloroflexi, and Acidobacteriota as the dominant bacterial phyla in the non-powered rural domestic wastewater treatment system. Among these, Proteobacteria and Bacteroidetes were primarily responsible for nitrogen and phosphorus removal, with their relative abundances ranging from 27.50% to 90.96% and 0.30% to 15.95%, respectively. At the genus level, the dominant taxa across all water samples (excluding S1 and X1) included norank_f__Rhodanobacteraceae, Castellaniella, Rhodanobacter, Acidocella, and Mycobacterium. Notably, the microbial composition in the second lower-layer sample (X2) exhibited significantly reduced diversity, dominated exclusively by Proteobacteria and Actinobacteriota. In conclusion, the non-powered wastewater treatment system demonstrates rich microbial diversity, which significantly enhances the treatment efficiency of rural domestic sewage.