title: Response of nitrite accumulation and microbial community to free ammonia and dissolved oxygen treatment of high ammonium wastewater.
abstract: The effects of free ammonia (FA) and dissolved oxygen (DO) on nitrite accumulation in the treatment of high ammonium wastewater and on the evolution of the microbial community were investigated. Under high DO conditions (3.75 ± 0.49 mg/L), FA as high as 10.61 ± 2.89 mg NH3/L maintained stable nitrite accumulation rate (NAR) of 84 % with NH4 (+)-N load of 2.05 kg N/(m(3) day) at sludge retention time (SRT) of 15-18 days. After 56 days of operation, Proteobacteria and Nitrosomonas were the dominant phylum and genus, respectively; Nitrosomonas increased from 21.14 to 54.57 %. By contrast, under relative low DO and low FA, nitrite-oxidizing bacteria (NOB) were nearly eliminated (NOB/AOB of 0; ammonium-oxidizing bacteria (AOB)), and NAR of 94 % was achieved with lower NH4 (+)-N load of 0.48 kg N/(m(3) day). DO correlated with AOB and NOB abundance, and FA decreased NOB activity and the NOB/AOB ratio. In conclusion, high FA and high DO conditions are optimal for efficient nitrite accumulation.
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.|The Key Laboratory of Energy Conservation and Waste Treatment of Agricultural Structures, Ministry of Agriculture, Beijing, 100081, China.|Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
authors.forename: Qianwen
authors.initials: Q
authors.lastname: Sui
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.|The Key Laboratory of Energy Conservation and Waste Treatment of Agricultural Structures, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Chong
authors.initials: C
authors.lastname: Liu
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
authors.forename: Junya
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China. donghongmin@caas.cn.|The Key Laboratory of Energy Conservation and Waste Treatment of Agricultural Structures, Ministry of Agriculture, Beijing, 100081, China. donghongmin@caas.cn.
authors.forename: Hongmin
authors.initials: H
authors.lastname: Dong
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.|The Key Laboratory of Energy Conservation and Waste Treatment of Agricultural Structures, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.|The Key Laboratory of Energy Conservation and Waste Treatment of Agricultural Structures, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000641:Ammonia / Q000378:metabolism*; D058448:Biota / Q000187:drug effects*; D009573:Nitrites / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D062065:Wastewater / Q000737:chemistry* / Q000382:microbiology*
chemical_list: D000641:Ammonia; D009573:Nitrites; D010100:Oxygen; D062065:Wastewater
keywords: Dissolved oxygen; Free ammonia; High-throughput sequencing; Microbial community; Nitrite accumulation