Carlier A. auteur aut IRD Chauvaud L. auteur aut IRD van der Geest M. auteur aut IRD Le Loc'h François auteur aut IRD Le Duff M. auteur aut IRD Vernet M. auteur aut IRD Raffray Jean auteur aut IRD Diakhate D. auteur aut IRD Labrosse P. auteur aut IRD Wague A. auteur aut IRD Le Goff C. auteur aut IRD Gohin F. auteur aut IRD Chapron B. auteur aut IRD Clavier J. auteur aut IRD text journalArticle eng text/pdf born digital access Banc d'Arguin (BA), Mauritania, is a nationally protected shallow gulf > 10,000 km(2) between the Sahara desert and the upwelling system off the Mauritanian coast. In the southeast, BA consists of a 500 km(2) tidal flat, the most important wintering site for shorebirds using the East Atlantic Flyway. The Mauritanian upwelling-driven phytoplankton production supports the most productive fisheries worldwide, but little is known about its trophic role in the functioning of the inshore BA food web. Using stable isotopes as trophic tracers to distinguish between upwelling-driven phytoplankton, open ocean phytoplankton, and benthic primary producers, we assessed the spatial extent to which the inshore BA food web is fuelled by upwelling-driven phytoplankton production. The delta C-13 and delta N-15 signals were characterized in dominant primary producers, benthic invertebrate taxa, and various fish species along an offshore inshore (northwest southeast) gradient. We also monitored the spatial and temporal extent of upwelling entering BA during 2008 with remote sensing of sea surface temperature and chlorophyll a data. The results suggest that benthic invertebrates and fishes living in the northwestern part of BA depend on the nearby upwelling phytoplankton production, but this food source does not support the intertidal benthic community in southeast BA. Furthermore, the isotopic signatures of fishes suggest weak trophic connectivity between the northern subtidal and southeastern intertidal BA. Our results support the hypothesis that the southeastern tidal flat region functions as a distinct ecosystem with a food web supported mainly by local benthic primary production, which is crucial knowledge for effective management of the pristine BA national park. specialized Banc d'Arguin West Africa food web structure remote sensing stable isotope upwelling MAURITANIE BANC D'ARGUIN 036 126 082 165 149-158 2015 0272-7714 https://www.documentation.ird.fr/hor/fdi:010066033 10.1016/j.ecss.2015.05.001 0272-7714 [F B010066033] https://www.documentation.ird.fr/hor/fdi:010066033 https://www.documentation.ird.fr/intranet/publi/2016/01/010066033.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2016-02-02 2017-08-23 fdi:010066033 fre