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Auteur (up) Lavaud, R.; Thébault, J.; Lorrain, A.; van der Geest, M.; Chauvaud, L. url  openurl
  Titre Senilia senilis (Linnaeus, 1758), a biogenic archive of environmental conditions on the Banc d'Arguin (Mauritania) Type Article scientifique
  Année 2013 Publication Revue Abrégée Journal of Sea Research  
  Volume 76 Numéro Pages 61-72  
  Mots-Clés Bivalve Sclerochronology Oxygen isotopes Barium Uranium anadara-senilis bivalve mollusk arctica-islandica isotope variation stable-isotopes mytilus-edulis trace-elements growth-rates in-situ shells  
  Résumé Environmental archives are useful tools for describing past and current climate variations and they provide an opportunity to assess the anthropogenic contribution in coastal ecological changes. Along the West African coast, few studies have focused on such archives in coastal ecosystems. The bloody cockle Senilia senilis, an intertidal bivalve mollusk species, is widely distributed from Western Sahara to Angola, and has been harvested by humans over thousands of years. Therefore, this species appears to be a good candidate for assessing past variations of key environmental parameters such as temperature, primary production, and Saharan dust advection within West African coastal ecosystems. In the present paper, we focused (i) on the identification of growth rhythms of S. senilis shells in Mauritania (Banc d'Arguin), and (ii) on the potential of these shells as (paleo-)environmental archives. The method we used combined environmental survey, sclerochronology, and geochemical analyses of aragonite samples. We showed that microgrowth line formation was controlled by a tidal forcing, leading to the formation of two lines per lunar day. Brightness and thickness of these microgrowth lines progressively decreased from spring to neap tides (fortnightly cycle). Lunar daily growth rates displayed strong seasonal variations, with highest values (>300 mu m per lunar day) recorded in summer. The oxygen isotope composition of S. senilis shells (delta O-18(aragonite)) accurately tracked seawater temperature seasonal variations, with a precision of 0.8 degrees C. Finally, we discussed the opportunity to use Ba:Ca ratio in shells as a proxy for primary production or for Saharan dust transport. We also hypothesized that either Canary Currentvariations or, more probably, massive aerosol transfers from Sahara to the Atlantic Ocean could control uranium availability in coastal waters and explain the occurrence of U:Ca peaks within S. senilis shells. (C) 2012 Elsevier B.V. All rights reserved.  
  Adresse [Lavaud, Romain; Thebault, Julien; Chauvaud, Laurent] Univ Brest, Inst Univ Europeen Mer, Lab Sci Environm Marin, CNRS IRD UBO UMR6539, F-29280 Plouzane, France. [Lorrain, Anne] IRD, Lab Sci Environm Marin, CNRS IRD UBO UMR6539, Noumea 98848, New Caledonia. [van der Geest, Matthijs] NIOZ Royal Netherlands Inst Sea Res, Dept Marine Ecol, NL-1790 AB Den Burg, Netherlands. Lavaud, R (reprint author), Univ Brest, Inst Univ Europeen Mer, Lab Sci Environm Marin, CNRS IRD UBO UMR6539, Rue Dumont dUrville, F-29280 Plouzane, France. romain.lavaud@univ-brest.fr  
  Auteur institutionnel Thèse  
  Editeur Lieu de Publication Éditeur  
  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1385-1101 ISBN Médium  
  Région Expédition Conférence  
  Notes ISI Document Delivery No.: 113EL Times Cited: 0 Cited Reference Count: 66 Lavaud, Romain Thebault, Julien Lorrain, Anne van der Geest, Matthijs Chauvaud, Laurent Oceanographic and Fisheries Research Mauritanian Institute (IMROP); Banc d'Arguin National Park (PNBA); Franco-Mauritanian PACOBA Project (Programme d'Amelioration des COnnaissances du Banc d'Arguin); French program ANR-Blanc CHIVAS (Chimie des valves de la coquille Saint-Jacques Europeenne); Institut de Recherche pour le Developpement (IRD); NWO-WOTRO Integrated Programme [W.01.65.221.00] We are grateful to J.-P. Barusseau for his precious help in understanding the morphodynamics and history of the Iwik region over the Holocene, therefore revealing the great potential of Senilia senilis settlements. We thank the Oceanographic and Fisheries Research Mauritanian Institute (IMROP) and the Banc d'Arguin National Park (PNBA) for their support. We also thank J. Clavier, P. Labrosse, E. Amice and L. Chinoise for field sampling, R. Mas for delta18O<INF>seawater</INF> measurements at the Vrije Universiteit Brussels (VUB, Belgium) and C. Bassoullet for her help during LA-ICP-MS analyses. We thank the two anonymous reviewers for helpful comments on the manuscript. Funding was provided by the Franco-Mauritanian PACOBA Project (Programme d'Amelioration des COnnaissances du Banc d'Arguin), the French program ANR-Blanc CHIVAS (Chimie des valves de la coquille Saint-Jacques Europeenne) and the Institut de Recherche pour le Developpement (IRD). MvdG was financially supported by the NWO-WOTRO Integrated Programme grant W.01.65.221.00 to Theunis Piersma. Elsevier science bv Amsterdam Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ 950 collection 1372  
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