title: Effect of gradual-increasing aeration mode in an aerobic tank on nutrients' removal and functional microbial communities.
abstract: Different aeration rates and modes in an aerobic tank of an anaerobic/anoxic/aerobic (A2O) process were investigated to reveal their influence on nitrogen and phosphorus removal efficiency. Meanwhile, Illumina high-throughput sequencing of partial 16S rRNA gene of bacteria was conducted to monitor the abundance and composition of microbial communities. The results showed that higher aeration rate led to better nutrients' removal efficiency. The gradual-increasing aeration mode along the wastewater stream enhanced the contaminants' removal and the system achieved chemical oxygen demand, [Formula: see text]-N, total nitrogen (TN) removal rates of 72%, 96% and 51%, respectively. However, the gradual-decreasing or uniform aeration modes resulted in inefficient removal of TN, especially the ammonia due to low DO in the end parts of A2O. Microbial community analysis indicated that denitrifying phosphorus-accumulating bacteria Acinetobacter spp. were the most dominant groups under the gradual-increasing aeration mode in all tanks of the A2O bioreactor. Moreover, the members of genera Clostridium, Thauera and Dechloromonas also largely existed in the system. The gradual-increasing aeration mode and cooperation of different groups of bacteria made the system stable and high-performance.
authors.affiliation: a Key Laboratory of Marine Environment and Ecology (Ocean University of China) , Ministry of Education , Qingdao , People's Republic of China.|b Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (MEGE) , College of Environmental Science and Engineering, Ocean University of China , Qingdao , People's Republic of China.
authors.forename: Yang-Guo
authors.initials: YG
authors.lastname: Zhao
authors.affiliation: b Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (MEGE) , College of Environmental Science and Engineering, Ocean University of China , Qingdao , People's Republic of China.
authors.forename: Xiaoma
authors.initials: X
authors.lastname: Guo
authors.affiliation: a Key Laboratory of Marine Environment and Ecology (Ocean University of China) , Ministry of Education , Qingdao , People's Republic of China.|b Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (MEGE) , College of Environmental Science and Engineering, Ocean University of China , Qingdao , People's Republic of China.
authors.forename: Zonglian
authors.initials: Z
authors.lastname: She
authors.affiliation: a Key Laboratory of Marine Environment and Ecology (Ocean University of China) , Ministry of Education , Qingdao , People's Republic of China.|b Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (MEGE) , College of Environmental Science and Engineering, Ocean University of China , Qingdao , People's Republic of China.
authors.forename: Mengchun
authors.initials: M
authors.lastname: Gao
authors.affiliation: a Key Laboratory of Marine Environment and Ecology (Ocean University of China) , Ministry of Education , Qingdao , People's Republic of China.|b Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (MEGE) , College of Environmental Science and Engineering, Ocean University of China , Qingdao , People's Republic of China.
authors.forename: Liang
authors.initials: L
authors.lastname: Guo
mesh_terms: D019149:Bioreactors; D058440:Denitrification; D009584:Nitrogen / Q000378:metabolism*; D010758:Phosphorus; D012336:RNA, Ribosomal, 16S; D012722:Sewage
chemical_list: D012336:RNA, Ribosomal, 16S; D012722:Sewage; D010758:Phosphorus; D009584:Nitrogen
keywords: Gradual-increasing aeration; high-throughput sequencing; microbial community; nitrogen and phosphorus removal; wastewater treatment