Articles | Volume 22, issue 19
https://doi.org/10.5194/bg-22-5387-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-5387-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
08 Oct 2025
Research article |
| 08 Oct 2025
| 08 Oct 2025
Aquatic metabolism influences temporal variations of water carbon and atmospheric carbon dioxide fluxes in a temperate salt marsh
Jérémy Mayen
CORRESPONDING AUTHOR
Ifremer, COAST, 17390 La Tremblade, France
Ifremer, COAST, 44000 Nantes, France
Univ. Bordeaux, CNRS, Bordeaux INP, EPOC, UMR 5805, 33600 Pessac, France
Pierre Polsenaere
Ifremer, COAST, 17390 La Tremblade, France
Aurore Regaudie de Gioux
Ifremer, DYNECO, 29280 Plouzané, France
Jonathan Deborde
Ifremer, COAST, 17390 La Tremblade, France
Karine Collin
Ifremer, COAST, 44000 Nantes, France
Yoann Le Merrer
Ifremer, COAST, 44000 Nantes, France
Élodie Foucault
MARBEC, Univ. Montpellier, CNRS, Ifremer, IRD, 34200 Sète, France
Vincent Ouisse
MARBEC, Univ. Montpellier, CNRS, Ifremer, IRD, 34200 Sète, France
Laurent André
BRGM, 45060 Orléans, France
ISTO, UMR7327, University of Orléans, CNRS, BRGM, OSUC, 45071 Orléans, France
Marie Arnaud
Ifremer, COAST, 17390 La Tremblade, France
Pierre Kostyrka
Ifremer, COAST, 17390 La Tremblade, France
Éric Lamaud
INRAE, Bordeaux Sciences Agro, ISPA, 33140 Villenave d'Ornon, France
Gwenaël Abril
Laboratoire de Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), UMR 8067, Muséum National d'Histoire Naturelle, CNRS, IRD, SU, UCN, UA, Paris, France
Philippe Souchu
Ifremer, COAST, 44000 Nantes, France
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Short summary
In a salt marsh, we performed seasonal 24 h cycles to look for aquatic metabolism influence on water carbon dynamics and net ecosystem CO2 exchanges (NEEs). From high to low tide in winter, marsh anaerobic respiration generated the highest levels of dissolved inorganic carbon and alkalinity. On the contrary, in spring and summer, marsh primary production led to CO2-depleted water exports downstream. At high tide, aquatic heterotrophy can influence NEE during the highest immersion levels only.
In a salt marsh, we performed seasonal 24 h cycles to look for aquatic metabolism influence on...
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