Nom du corpus

Corpus Systématique Végétale

Titre du document

Nitrification, denitrification, and nitrate ammonification in sediments of two coastal lagoons in Southern France

Lien vers le document
Éditeur
Springer (journals)
Langue(s) du document
Anglais
Type de document
Research-article
Mots-clés d'auteur
  • Nitrification
  • denitrification
  • nitrate
  • ammonification
  • sediments
  • isotope
  • 15N
  • ammonium
  • flux
Nom du fichier dans la ressource
Syst_veg6_v2_026304
Auteur(s)
  • Søren Rysgaard 1
  • Nils Risgaard-Petersen 1
  • Niels Peter Sloth 2
Affiliation(s)
  • 1) National Environmental Research Institute, Vejlsøvej 25, 8600, Silkeborg, Denmark
  • 2) Department of Microbial Ecology, Institute of Biological Sciences, University of Aarhus, Bd. 540, DK-8000, Aarhus C, Denmark
Résumé

Seasonal and diurnal variations in sediment-water fluxes of O2, NO 3 − , and NH 4 + as well as rates of nitrification, denitrification, and nitrate ammonification were determined in two different coastal lagoons of southern France: The seagrass (Zostera noltii) dominated tidal Bassin d'Arcachon and the dystrophic Etang du Prévost. Overall, denitrification rates in both Bassin d'Arcachon (<0.4 mmol m−2 d−1) and Etang du Prévost (<1 mmol m−2 d−1) were low. This was mainly caused by a combination of low NO 3 − concentrations in the water column and a low nitrification activity within the sediment. In both Bassin d'Arcachon and Etang du Prévost, rates of nitrate ammonification were quantitatively as important as denitrification. Denitrification played a minor role as a nitrogen sink in both systems. In the tidal influenced Bassin d'Arcachon, Z. noltii was quantitatively more important than denitrification as a nitrogen sink due to the high assimilation rates of the plants. Throughout the year, Z. noltii stabilized the mudflats of the bay by its well- developed root matrix and controlled the nitrogen cycle due to its high uptake rates. In contrast, the lack of rooted macrophytes, and dominance of floating macroalgae, made nitrogen cycling in Etang du Prévost more unstable and unpredictable. Inhibition of nitrification and denitrification during the dystrophic crisis in the summer time increased the inorganic nitrogen flux from the sediment to the water column and thus increased the degree of benthic-pelagic coupling within this bay. During winter, however, benthic microalgae colonizing the sediment surface changed the sediment in the lagoon from being a nitrogen source to the over lying water to being a sink due to their high assimilation rates. It is likely, however, that this assimilated nitrogen is liberated to the water column at the onset of summer thereby fueling the extensive growth of the floating macroalgae, Ulva sp. The combination of a high nitrogen coupling between sediment and water column, little water exchange and low denitrification rates resulted in an unstable system with fast growing algal species such as phytoplankton and floating algae.

Catégories Science-Metrix
  • 1 - natural sciences
  • 2 - biology
  • 3 - marine biology & hydrobiology
Catégories INIST
  • 1 - sciences appliquees, technologies et medecines
  • 2 - sciences biologiques et medicales
  • 3 - sciences biologiques fondamentales et appliquees. psychologie
  • 4 - ecologie animale, vegetale et microbienne
Catégories Scopus
  • 1 - Life Sciences ; 2 - Agricultural and Biological Sciences ; 3 - Aquatic Science
Catégories WoS
  • 1 - science ; 2 - marine & freshwater biology
Identifiant ISTEX
0E8F29AB6AEE84D4247149E1CCF0C754C47833A9
Revue

Hydrobiologia

Année de publication
1996
Présence de XML structuré
Non
Score qualité du texte
10
Version PDF
1.3
Type de publication
Journal
ark:/67375/1BB-0BPP6B22-P
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