Assessment of Ba/Ca in Arctica islandica shells as a proxy for phytoplankton dynamics in the Northwestern Atlantic Ocean

• Published in: Estuarine, Coastal and Shelf Science
• Main Authors: Doré, Justine, Chaillou, Gwenaëlle, Poitevin, Pierre, Lazure, Pascal, Poirier, André, Chauvaud, Laurent, Archambault, Philippe, Thébault, Julien
• Other Authors: 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 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), Institut des Sciences de la MER de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Centre de recherche sur la dynamique du système Terre (GEOTOP), Université de Montréal (UdeM)-McGill University = Université McGill Montréal, Canada -École Polytechnique de Montréal (EPM)-Concordia University Montreal -Université du Québec à Rimouski (UQAR)-Université du Québec à Montréal = University of Québec in Montréal (UQAM)-Université du Québec en Abitibi-Témiscamingue (UQAT), Departement de Biologie Québec, Université Laval Québec (ULaval), This research is a contribution of LIA-BeBEST, an international collaboration between French (IUEM-UBO, LEMAR - Brest) and Canadian (ISMER-UQAR, Rimouski) academic institutions. We thank the LEMAR and the DFO for their help. We are sincerely grateful to Dr. Virginie Roy (MLI, Quebec-Canada) for her relevant advice and her kindness. In addition, we express our sincere gratitude to Dr. Simon B.elanger (UQAR) and Dr. Peter Galbraith (MLI) for their help to disentangle the information and Herl.e Goraguer (Ifremer delegate in SPM) for his commitment to the preparation and sending of a part of the samples. We show our appreciation to Laure Devine and Hannah Whitby for their useful comments. We also thank Eric Dabas for his technical assistance in the sclerochronology process. Finally, we would like to thank the two anonymous reviewers for their valuable comments and suggestions in a previous version of the manuscript. This research was supported by a grant from the Natural Sciences and Engineering Research Council of Canada (to G.C.) and the Canada Research Chair Program (to G.C.) as well as the Region Bretagne and the Cluster of Excellence LabexMER. This research was carried out as part of the Ph.D. thesis of Justine Dore for the University of Western Brittany. All the data used to produce the results of this paper may be obtained by contacting the corresponding author., ANR-10-LABX-0019,LabexMER,LabexMER Marine Excellence Research: a changing ocean(2010)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: Northwestern Atlantic; Master chronology; Cross-dating; Chlorophyll; Ba/Ca; ACL; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Arctica islandica; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-02921200; https://doi.org/10.1016/j.ecss.2020.106628

International audience Despite its major role as a global climate regulator, little is known about the recent evolution of the North Atlantic Ocean, especially prior to the fifties, principally because of the lack of long-term instrumental data. Moreover, the North Atlantic Ocean is undergoing rapid changes at the physical scale leading to modifications at the biological scale increasing interest to monitor the environment. The phytoplankton is the base of the ocean life and its perturbation can lead to further changes in the food chain. Recording its dynamics implies to observe both its spatial and temporal variations. This study brings forward the use of the Ba/Ca ratio from shells of the long-living bivalve Arctica islandica collected in the Northwestern Atlantic Ocean near Saint-Pierre and Miquelon (SPM) as a recorder of the past and present phytoplankton dynamics. A high inter and intra-reproducibility and synchrony between Ba/Cashell profiles were demonstrated allowing the reconstruction of a 124 years annually-resolved Ba/Cashell master chronology (from 1893 to 2016). This master chronology was positively correlated to the surface chlorophyll a measured by satellite sensor at regional (around SPM) and global scales (Northwestern Atlantic).