New primary production and nitrification in the western subtropical North Atlantic: A modeling study

• Published in: Global Biogeochemical Cycles
• Main Authors: Martin, Adrian, Pondaven, Philippe
• Other Authors: National Oceanography Centre (NOC), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2006
• Subjects: US JGOFS BERMUDA; OCEAN DESERTS BLOOM; SARGASSO SEA; TIME-SERIES; MESOSCALE EDDIES; EUPHOTIC ZONE; NITRATE FLUX; NITROGEN; OXYGEN; EXPORT; [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography; North Atlantic
• Online Access: https://hal.univ-brest.fr/hal-00472060; https://hal.univ-brest.fr/hal-00472060/document; https://hal.univ-brest.fr/hal-00472060/file/2005GB002608.pdf; https://doi.org/10.1029/2005GB002608

International audience The original definition of new primary production rests on the assumption that nitrogenous substrate taken up to fuel algal growth is coming into contact with phytoplankton for the first time that year. Therefore, should the generation of nitrate from ammonium by nitrification turn out to be significant in surface waters then nitrate uptake can no longer be simply ascribed to new production. A modeling study is presented centered on the Bermuda Atlantic Time-series Station, in the oligotrophic subtropical North Atlantic. We quantify the role of nitrification in providing nitrate to fuel primary production through a full annual cycle for the first time. The results confirm previous limited observations suggesting that a major fraction of nitrate uptake in oligotrophic regions ( where nitrification will be most influential), previously ascribed to new production, may actually involve "recycled'' nitrate.