title: The effects of salinity on coupled nitrification and aerobic denitrification in an estuarine system.
abstract: Salinity has significant effects on nitrification and denitrification processes, particularly in estuarine systems. A dissolved oxygen-enriched river and its estuary in northern China were selected to investigate the impact of salinity gradients (0.6, 4, 7.6, 11.4 and 14.7‰) obtained from the mixing of river samples and estuarine samples with different proportions on coupled nitrification and aerobic denitrification via incubation experiments (35 and 10 °C). Results indicated that: (a) nitrification and coupled nitrification-aerobic denitrification occurred for all treatments, which resulted in NO3- being either accumulated or removed at the end of the incubation; (b) a suitable range of salinity is 4.0-11.4‰ for nitrification and 4.0-7.6‰ for coupled nitrification-aerobic denitrification; and (c) the relatively higher temperature (35 °C) can effectively stimulate N transformation processes compared to the lover temperature (10 °C) in the incubation experiment.
authors.affiliation: Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China E-mail: xuedongmei@gmail.com; Urban and Environmental Science College, Tianjin Normal University, Tianjin 300387, China.
authors.forename: Mengfan
authors.initials: M
authors.lastname: Yang
authors.affiliation: Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China E-mail: xuedongmei@gmail.com.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Xue
authors.affiliation: College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Fanqiao
authors.initials: F
authors.lastname: Meng
authors.affiliation: Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China E-mail: xuedongmei@gmail.com; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
authors.forename: Zhong-Liang
authors.initials: ZL
authors.lastname: Wang
mesh_terms: D000332:Aerobiosis; D000641:Ammonia / Q000378:metabolism; D002681:China; D058440:Denitrification; D063366:Estuaries; D009566:Nitrates / Q000378:metabolism; D058465:Nitrification; D009584:Nitrogen / Q000378:metabolism*; D054712:Salinity; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D009566:Nitrates; D014874:Water Pollutants, Chemical; D000641:Ammonia; D009584:Nitrogen