Potential rates and environmental controls of anaerobic ammonium oxidation in estuarine sediments

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Teixeira, C (Author) Other; Magalhaes, C (Author) Other; Joye, SB (Author) Other; Adriano Bordalo (Author) ICBAS

Journal

Title: Aquatic Microbial Ecology

Vol. 66

Pages: 23-32

ISSN: 0948-3055

Publisher: Inter-Research Science Publishing

Indexing

ISI Web of Knowledge - 36 Citations

Scopus - 40 Citations

Other information

Authenticus ID: P-002-GM6

DOI: 10.3354/ame01548

Abstract (EN): The importance of anaerobic ammonium oxidation (anammox)-a metabolic pathway that can generate dinitrogen-remains poorly described in temperate estuarine systems. We evaluated the relative importance of anammox and denitrification along the salinity gradient of the Cavado River estuary (NW Portugal) during a seasonal survey. Potential rates of anammox and denitrification 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 parameters such as salinity, temperature and inorganic nitrogen were also monitored. Anammox and denitrification potentials in Cavado estuarine sediments varied from 0 to 3.3 and from 1.1 to 10.8 nmol N cm(-3) wet sediment h(-1), respectively. During 1 sampling occasion, anammox activity accounted for as much as 72% of the measured production of dinitrogen, while annual averages varied from 17 to 33% depending on location. Nitrate availability and temperature appeared to be the primary environmental controls of anammox. Higher concentrations of NO3- and intermediate temperatures in the estuarine water (14 to 16 degrees C) supported higher anammox activities. Using 16S rRNA gene-specific primers, anammox-like bacterial sequences were recovered from Cavado sediments-corroborating the measured anammox activities. Our results support the environmental importance of anammox for removal of nitrogen in estuarine sediments, and suggest that this process is apparently regulated by few variables.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10