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Live (Stained) Benthic Foraminifera Off Walvis Bay, Namibia: A Deep-Sea Ecosystem under the Influence of Bottom Nepheloid Layers

2013; Cushman Foundation for Foraminiferal Research; Volume: 43; Issue: 1 Linguagem: Inglês

10.2113/gsjfr.43.1.55

1943-264X

Christophe Fontanier, Édouard Metzger, Claire Waelbroeck, M. Jouffreau, N. LeFloch, Frans Jorissen, Henri Etcheber, Sabrina Bichon, G. Chabaud, Dominique Poirier, Antoine Grémare, Bruno Deflandre,

Geological formations and processes

Research Article| January 01, 2013 Live (Stained) Benthic Foraminifera Off Walvis Bay, Namibia: A Deep-Sea Ecosystem under the Influence of Bottom Nepheloid Layers Christophe Fontanier; Christophe Fontanier 4 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France 4 Correspondence author. Email: christophe.fontanier@univ-angers.fr Search for other works by this author on: GSW Google Scholar Edouard Metzger; Edouard Metzger 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France Search for other works by this author on: GSW Google Scholar Claire Waelbroeck; Claire Waelbroeck 3 Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Search for other works by this author on: GSW Google Scholar MÉlissa Jouffreau; MÉlissa Jouffreau 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France Search for other works by this author on: GSW Google Scholar Nina LeFloch; Nina LeFloch 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France Search for other works by this author on: GSW Google Scholar Frans Jorissen; Frans Jorissen 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France Search for other works by this author on: GSW Google Scholar Henri Etcheber; Henri Etcheber 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Search for other works by this author on: GSW Google Scholar Sabrina Bichon; Sabrina Bichon 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Search for other works by this author on: GSW Google Scholar Gérard Chabaud; Gérard Chabaud 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Search for other works by this author on: GSW Google Scholar Dominique Poirier; Dominique Poirier 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Search for other works by this author on: GSW Google Scholar Antoine Grémare; Antoine Grémare 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Search for other works by this author on: GSW Google Scholar Bruno Deflandre Bruno Deflandre 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Search for other works by this author on: GSW Google Scholar Author and Article Information Christophe Fontanier 4 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Edouard Metzger 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France Claire Waelbroeck 3 Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France MÉlissa Jouffreau 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France Nina LeFloch 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France Frans Jorissen 1 Laboratory of Recent and Fossil Bio-Indicators, UNAM, UMR 6112 CNRS LPGN, 2 Boulevard Lavoisier, 49045 Angers Cedex, France Henri Etcheber 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Sabrina Bichon 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Gérard Chabaud 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Dominique Poirier 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Antoine Grémare 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France Bruno Deflandre 2 Environnements et Paléo-environnements Océaniques et Continentaux, University of Bordeaux I, UMR 5805 CNRS, Avenue des Facultés, 33405 Talence Cedex, France, Laboratoire des Sciences du Climat et de l'Environnement, UMR 1572 CEA-CNRS-UVSQ, F-91198 Gif-sur-Yvette Cedex, France 4 Correspondence author. Email: christophe.fontanier@univ-angers.fr Publisher: Cushman Foundation for Foraminiferal Research Received: 10 Feb 2012 Accepted: 23 Oct 2012 First Online: 13 Jul 2017 Online ISSN: 1943-264X Print ISSN: 0096-1191 © 2013 Cushman Foundation for Foraminiferal Research Journal of Foraminiferal Research (2013) 43 (1): 55–71. https://doi.org/10.2113/gsjfr.43.1.55 Article history Received: 10 Feb 2012 Accepted: 23 Oct 2012 First Online: 13 Jul 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Christophe Fontanier, Edouard Metzger, Claire Waelbroeck, MÉlissa Jouffreau, Nina LeFloch, Frans Jorissen, Henri Etcheber, Sabrina Bichon, Gérard Chabaud, Dominique Poirier, Antoine Grémare, Bruno Deflandre; Live (Stained) Benthic Foraminifera Off Walvis Bay, Namibia: A Deep-Sea Ecosystem under the Influence of Bottom Nepheloid Layers. Journal of Foraminiferal Research 2013;; 43 (1): 55–71. doi: https://doi.org/10.2113/gsjfr.43.1.55 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyJournal of Foraminiferal Research Search Advanced Search Abstract We present an ecological investigation of live (stained) foraminiferal faunas (>150-μm fraction) from four deep-sea stations sampled in the eastern South Atlantic off Walvis Bay, Namibia. These stations describe a bathymetric transect from ~900 to ~3000-m depth, below the oxygen minimum zone related to the Benguela upweling system. The mineralization of organic detritus, as suggested by oxygen-penetration depths and ΔpH depth profiles, is relatively intense along the overall bathymétrie transect. Organic carbon and amino-acid contents in the surface sediment are high between ~900-2000-m depth (e.g., Corg > 1.7%, THAA > 47 nmol/mg), and decrease along the bathymétrie transect. Carbon-14 ages and grain-size distribution determined for the upper sediment suggest a complex balance between erosion, transportation, and deposition at all stations. Bottom nepheloid layers (BNLs) are well-documented in our study area. They are relevant candidates for the dispersion and accumulation of reworked organic compounds along the Namibian slope. Foraminiferal faunas living at the three shallower sites are characterized by species (e.g., Cibicidoides kullembergi, Bulimina inflatalcostata) related to the enhanced productivity. The occurrence of epibiotic species (Cibicides refulgens, Gavelinopsis translucens, and C kullenbergi) argues for bottom currents supplying organic compounds in suspension above the sediment-water interface. In those environmental conditions, Reophax bilocularis, R. pilulifer, and Lagenammina difflugiformis contribute significantly to live communities, especially at the lower-slope site. Live foraminiferal faunas are largely restricted to shalow-infaunal oxygenated microhabitats. Finally, we propose that hydro-sedimentary conditions characterized by more or less intermittent near-bottom currents 1) trigger the dominance of arenaceous faunas and 2) preclude the proliferation of a foraminiferal population in deep-infaunal microhabitats. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.