Abundance and Niche Differentiation of Comammox in the Sludges of Wastewater Treatment Plants That Use the Anaerobic–Anoxic–Aerobic Process
Sheng-Nan Zhang,
Jian-Gong Wang,
Dan-Qi Wang,
Qiu-Yue Jiang,
Zhe-Xue Quan
Affiliations
Sheng-Nan Zhang
Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Biodiversity Science and Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai 200433, China
Jian-Gong Wang
Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Biodiversity Science and Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai 200433, China
Dan-Qi Wang
Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Biodiversity Science and Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai 200433, China
Qiu-Yue Jiang
Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Biodiversity Science and Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai 200433, China
Zhe-Xue Quan
Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Biodiversity Science and Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai 200433, China
Complete ammonia oxidizers (comammox), which directly oxidize ammonia to nitrate, were recently identified and found to be ubiquitous in artificial systems. Research on the abundance and niche differentiation of comammox in the sludges of wastewater treatment plants (WWTPs) would be useful for improving the nitrogen removal efficiency of WWTPs. Here, we investigated the relative abundance and diversity of comammox in fifteen sludges of five WWTPs that use the anaerobic–anoxic–aerobic process in Jinan, China, via quantitative polymerase chain reaction and high-throughput sequencing of the 16S rRNA gene and ammonia monooxygenase gene. In the activated sludges in the WWTPs, comammox clade A.1 was widely distributed and mostly comprised Candidatus Nitrospira nitrosa-like comammox (>98% of all comammox). The proportion of this clade was negatively correlated (p Nitrospira lineage I frequently coexisted with Nitrosomonas, which generally had a significant positive correlation (p < 0.05) with the DO level. Our study provided an insight into the structure of comammox and other nitrifier populations in WWTPs that use the anaerobic–anoxic–aerobic process, broadening the knowledge about the effects of DO on comammox and other nitrifiers.