Analysis of key microbial community during the start-up of anaerobic ammonium oxidation process with paddy soil as inoculated sludge

A sequencing batch reactor (SBR)-anaerobic ammonium oxidation (anammox) system was started upwith the paddy soil as inoculated sludge. The key microbial community structure in the system along with the enrichment time was investigated by using molecular biology methods (e.g., high-throughput 16S rRNA gene sequencing and quantitative PCR). Meanwhile, the influent and effluent water quality was continuously monitored during the whole start-up stage. The results showed that the microbial diversity decreased as the operation time initially and increased afterwards, and the microbial niches in the system were redistributed. The anammox bacterial community structure in the SBR-anammox system shifted during the enrichment, the most dominant anammox bacteria were Candidatus Jettenia. The maximum biomass of anammox bacteria achieved 1.68 x 10(9) copies/g dry sludge during the enrichment period, and the highest removal rate of TN achieved around 75%. (c) 2017 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.