京津冀区域市政污水厂活性污泥种群结构的多样性及差异

【背景】活性污泥中微生物的种群结构影响着污水生物处理的高效性及稳定性,是有效保证污水处理效果的关键。【目的】研究活性污泥中细菌的群落结构组成及多样性,并分析相应菌群的主要功能,旨在更好地发挥细菌的净化作用、保持污水处理过程的稳定及提高污水的处理效率。【方法】以京津冀区域内典型市政污水厂活性污泥为研究对象,通过IlluminaMiSeq高通量测序及实时定量PCR技术,对5个污水厂活性污泥的微生物种群结构特征进行了详细解析,研究不同工艺参数下活性污泥中优势种群及脱氮菌群丰度的差异。【结果】5个污水厂活性污泥种群结构具有一定差异,其中Hengshui (HS)厂污泥的群落结构受温度的影响最大,而Shahe (SH)、Daoxianghu (DXH)、Nangong(NG)厂活性污泥群落结构则受总氮、总磷与氨氮的共同影响,氨氮对SH厂活性污泥种群结构影响最大。DXH、NG和HS厂污泥中优势菌均为Anaerolineaceae,而SH和Hejian (HJ)厂的优势菌则为Saprospiraceae与Lactobacillus。活性污泥中反硝化菌丰度最高的为HJ厂,丰度最低的为HS厂,反硝化功能基因nirS比nirK分布更为广泛。【结论】对于不同污水厂,影响其活性污泥群落结构组成的环境因素也是不同的,并且特殊的进水水质也会对污泥菌群组成和生物多样性产生影响。

Microbial community diversity of activated sludge from municipal wastewater treatment plants in Beijing-Tianjin-Hebei region

Background] Bacterial community structure of activated sludge has important impacts on the high efficiency and stability of the biological sewage treatment. Objective] In order to provide strategies for maintaining stability of sewage disposal process and improving sewage treatment efficiency, we have estimated bacterial community structure and function of activated sludge. Methods] Illumina MiSeq sequencing and real-time PCR were applied to analyze the bacterial community structure diversity and differences of the activated sludge, which was sampled from five municipal wastewater treatment plants in the Beijing-Tianjin-Hebei region. Results] Sample from Hengshui (HS) demonstrated the highest microbial diversity and occupied the most unique OTUs whereas sample Hejian (HJ) demonstrated the lowest microbial diversity. Influent temperature was the principal factor that differed the sample HS from other samples in community structure. The most dominant families of sample Daoxianghu (DXH), Nangong (NG) and HS were all Anaerolineaceae, whereas the most dominant families or genera of sample Shahe (SH) and HJ were Saprospiraceae and Lactobacillus respectively. Sample HJ demonstrated the highest denitrifier abundance, whereas sample HS demonstrated the lowest denitrifier abundance. Furthermore, nirS gene was the more widely distributed nitrite reductase encoding gene than nirK gene. Conclusion] The environmental vectors affecting community structure of activity sludge in different municipal wastewater treatment plants were discrepant. And special influent water quality would also have effect on community composition and biodiversity.