The contribution of anaerobic ammonium oxidation to nitrogen loss in two temperate eutrophic estuaries

作者：Teixeira Catarina^*; Magalhaes Catarina; Joye Samantha B; Bordalo Adriano A

来源：Estuarine, Coastal and Shelf Science, 2014, 143: 41-47.

DOI：10.1016/j.ecss.2014.03.023

• anammox
• nitrogen
• sediments
• estuary

Studies of anaerobic ammonium oxidation (anammox) continue to show the significance of this metabolic pathway for the removal of nitrogen (N) in several natural environments, including estuaries. However, the seasonal dynamics of the anammox process and related environmental controls within estuarine systems remains poorly explored. We evaluated the seasonal anammox activity along a salinity gradient in two temperate Atlantic estuaries, the Ave and the Douro (NW Portugal). Anammox potential rates were measured in anaerobic sediment slurries using N-15-labeled NO3- and NH4+ amendments. Production of N-29(2) and N-30(2) in the slurries was quantified using membrane inlet mass spectrometry (MIMS). Environmental characteristics of the sediment and water column were also monitored. Anammox potentials in the Ave and Douro estuarine sediments varied between 0.8-8.4, and 0-2.9 nmol cm(-3) wet sediment h(-1), respectively, with high seasonal and spatial fluctuations. Inorganic nitrogen availability emerged as the primary environmental control of anammox activity, while water temperature appeared to modulate seasonal variations. The contribution of anammox to overall N-2 production averaged over 20%, suggesting that the role of anammox in removing fixed N from these two systems cannot be neglected.

• 出版日期2014-4-20