title: Evidence for anaerobic ammonium oxidation process in freshwater sediments of aquaculture ponds.
abstract: The anaerobic ammonium oxidation (anammox) process, which can simultaneously remove ammonium and nitrite, both toxic to aquatic animals, can be very important to the aquaculture industry. Here, the presence and activity of anammox bacteria in the sediments of four different freshwater aquaculture ponds were investigated by using Illumina-based 16S rRNA gene sequencing, quantitative PCR assays and (15)N stable isotope measurements. Different genera of anammox bacteria were detected in the examined pond sediments, including Candidatus Brocadia, Candidatus Kuenenia and Candidatus Anammoxoglobus, with Candidatus Brocadia being the dominant anammox genus. Quantitative PCR of hydrazine synthase genes showed that the abundance of anammox bacteria ranged from 5.6 × 10(4) to 2.1 × 10(5) copies g(-1) sediment in the examined ponds. The potential anammox rates ranged between 3.7 and 19.4 nmol N2 g(-1) sediment day(-1), and the potential denitrification rates varied from 107.1 to 300.3 nmol N2 g(-1) sediment day(-1). The anammox process contributed 1.2-15.3% to sediment dinitrogen gas production, while the remainder would be due to denitrification. It is estimated that a total loss of 2.1-10.9 g N m(-2) per year could be attributed to the anammox process in the examined ponds, suggesting that this process could contribute to nitrogen removal in freshwater aquaculture ponds.
authors.affiliation: Jiangsu Key Laboratory of Agricultural Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.|Department of Agricultural Resource and Environment, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
authors.forename: Li-dong
authors.initials: LD
authors.lastname: Shen
authors.affiliation: Jiangsu Key Laboratory of Agricultural Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.|Department of Agricultural Resource and Environment, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
authors.forename: Hong-sheng
authors.initials: HS
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Science, Beijing, China. zgao@mail.iap.ac.cn.|College of Geophysics and Remote Sensing, Nanjing University of Information Science and Technology, Nanjing, 210044, China. zgao@mail.iap.ac.cn.
authors.forename: Zhi-qiu
authors.initials: ZQ
authors.lastname: Gao
authors.affiliation: Institute of Agricultural Bio-Environmental Engineering, College of Bio-systems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Yun-jie
authors.initials: YJ
authors.lastname: Ruan
authors.affiliation: Jiangsu Key Laboratory of Agricultural Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.|Department of Agricultural Resource and Environment, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
authors.forename: Xiang-hua
authors.initials: XH
authors.lastname: Xu
authors.affiliation: Department of Agricultural Resource and Environment, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Agricultural Resource and Environment, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
authors.forename: Shi-jie
authors.initials: SJ
authors.lastname: Ma
authors.affiliation: Department of Agricultural Resource and Environment, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
authors.forename: Pei-hui
authors.initials: PH
authors.lastname: Zheng
mesh_terms: D064751:Ammonium Compounds / Q000378:metabolism*; D000693:Anaerobiosis; D017756:Aquaculture; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D058440:Denitrification; D019015:Geologic Sediments / Q000382:microbiology*; D009573:Nitrites / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D061005:Ponds / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D064751:Ammonium Compounds; D009573:Nitrites; D012336:RNA, Ribosomal, 16S; D009584:Nitrogen
keywords: Activity; Anaerobic ammonium oxidation (anammox); Distribution; Freshwater aquaculture ponds; Illumina-based 16S rRNA gene sequencing; Nitrogen removal