Deborde J. auteur aut IRD Anschutz P. auteur aut IRD Guérin Frédéric auteur aut IRD Poirier D. auteur aut IRD Marty D. auteur aut IRD Boucher G. auteur aut IRD Thouzeau G. auteur aut IRD Canton M. auteur aut IRD Abril G. auteur aut IRD text journalArticle eng text/pdf born digital access The Arcachon lagoon is a 156 km(2) temperate mesotidal lagoon dominated by tidal flats (66% of the surface area). The methane (CH4) sources, sinks and fluxes were estimated from water and pore water concentrations, from chamber flux measurements at the sediment air (low tide), sediment-water and water-air (high tide) interfaces, and from potential oxidation and production rate measurements in sediments. CH4 concentrations in waters were maximal (500-1000 nmol l(-1)) in river waters and in tidal creeks at low tide, and minimal in the lagoon at high tide (<50 nmol l(-1)). The major CH4 sources are continental waters and the tidal pumping of sediment pore waters at low tide. Methanogenesis occurred in the tidal flat sediments, in which pore water concentrations were relatively high (2.5-8.0 mu mol l(-1)) Nevertheless, the sediment was a minor CH4 source for the water column and the atmosphere because of a high degree of anaerobic and aerobic CH4 oxidation in sediments. Atmospheric CH4 fluxes at high and low tide were low compared to freshwater wetlands. Temperate tidal lagoons appear to be very minor contributor of CH4 to global atmosphere and to open ocean. specialized methane chamber flux measurements coastal environment Arcachon Lagoon 032 89 4 256-266 2010 0272-7714 https://www.documentation.ird.fr/hor/fdi:010052883 10.1016/j.ecss.2010.07.013 0272-7714 [F B010052883] https://www.documentation.ird.fr/hor/fdi:010052883 https://www.documentation.ird.fr/intranet/publi/2010/11/010052883.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2010-12-03 2017-08-23 fdi:010052883 fre