Consulta: creatorFacets:"Bessette, Sandrine"
Registros recuperados: 4
Data/hora: 09/06/2024 04:29:00

Early diagenesis in the sediments of the Congo deep-sea fan dominated by massive terrigenous deposits: Part III – Sulfate- and methane- based microbial processes
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Pastor, Lucie; Toffin, Laurent; Decker, Carole; Olu, Karine; Cathalot, Cecile; Lesongeur, Francoise; Caprais, Jean-claude; Bessette, Sandrine; Brandily, Christophe; Taillefert, M.; Rabouille, C.
Geochemical profiles (SO42-, H2S, CH4, δ13CH4) and phylogenetic diversity of Archaea and Bacteria from two oceanographic cruises dedicated to the lobes sediments of the Congo deep-sea fan are presented in this paper. In this area, organic-rich turbidites reach 5000 m and allow the establishment of patchy cold-seep-like habitats including microbial mats, reduced sediments, and vesicomyid bivalves assemblages. These bivalves live in endosymbiosis with sulfur-oxidizing bacteria and use sulfides to perform chemosynthesis. In these habitats, unlike classical abyssal sediments, anoxic processes are dominant. Total oxygen uptake fluxes and methane fluxes measured with benthic chambers are in the same range as those of active cold-seep environments, and oxygen is...
Tipo: Text
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00376/48767/49164.pdf

Relative abundance and diversity of bacterial methanotrophs at the oxic-anoxic interface of the Congo deep-sea fan
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Bessette, Sandrine; Moalic, Yann; Gautey, Sebastien; Lesongeur, Francoise; Godfroy, Anne; Toffin, Laurent.
Sitting at ~5 000 m water depth on the Congo-Angola margin and ~ 760 km offshore of the West African coast, the recent lobe complex of the Congo deep-sea fan receives large amounts of fluvial sediments (3-5% organic carbon). This organic-rich sedimentation area harbors habitats with chemosynthetic communities similar to those of cold seeps. In this study, we investigated relative abundance, diversity and distribution of aerobic methane-oxidizing bacteria (MOB) communities at the oxic-anoxic interface of sedimentary habitats by using fluorescence in situ hybridization and comparative sequence analysis of particulate mono-oxygenase (pmoA) genes. Our findings revealed that sedimentary habitats of the recent lobe complex hosted type I and type II MOB cells and...
Tipo: Text
Palavras-chave: Aerobic methane-oxidizing bacteria; PmoA; Organic-rich sediment; Methane seeps; Congo deep-sea fan.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00382/49327/49706.pdf

The Congolobe project, a multidisciplinary study of Congo deep-sea fan lobe complex: Overview of methods, strategies, observations and sampling
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Rabouille, C.; Olu, Karine; Baudin, F.; Khripounoff, Alexis; Dennielou, Bernard; Arnaud-haond, Sophie; Babonneau, Nathalie; Bayle, Christophe; Beckler, J.; Bessette, Sandrine; Bombled, B.; Bourgeois, S.; Brandily, Christophe; Caprais, Jean-claude; Cathalot, Cecile; Charlier, K.; Corvaisier, R.; Croguennec, Chantal; Cruaud, Perrine; Decker, Carole; Droz, L.; Gayet, Nicolas; Godfroy, Anne; Hourdez, S.; Le Bruchec, J.; Saout, Johan; Le Saout, Marie-helene; Lesongeur, Francoise; Martinez, P.; Mejanelle, L.; Michalopoulos, P.; Mouchel, Olivier; Noel, Philippe; Pastor, Lucie; Picot, M.; Pignet, Patricia; Pozzato, L.; Pruski, A. M.; Rabiller, Manuella; Raimonet, M.; Ragueneau, O.; Reyss, J. L.; Rodier, Philippe; Ruesch, Blandine; Ruffine, Livio; Savignac, F.; Senyarich, C.; Schnyder, J.; Sen, Arunima; Stetten, E.; Sun, Ming Yi; Taillefert, M.; Teixeira, S.; Tisnerat-laborde, N.; Toffin, Laurent; Tourolle, Julie; Toussaint, F.; Vetion, G.; Jouanneau, J. M.; Bez, M.
The presently active region of the Congo deep-sea fan (around 330 000 km2), called the terminal lobes or lobe complex, covers an area of 2500 km2 at 4700–5100 m water depth and 750–800 km offshore. It is a unique sedimentary area in the world ocean fed by a submarine canyon and a channel-levee system which presently deliver large amounts of organic carbon originating from the Congo River by turbidity currents. This particularity is due to the deep incision of the shelf by the Congo canyon, up to 30 km into the estuary, which funnels the Congo River sediments into the deep-sea. The connection between the river and the canyon is unique for major world rivers.  In 2011, two cruises (WACS leg 2 and Congolobe) were conducted to simultaneously investigate the...
Tipo: Text
Palavras-chave: Chemosynthetic habitats; Congo deep-sea fan; Fine sediment; Sedimentation rate; Seafloor morphology; Turbidite; Vesicomyidae.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00335/44580/44298.pdf

Identification des communautés microbiennes des lobes terminaux du système turbiditique du Congo
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Bessette, Sandrine.
The Congo deep sea fan, located in the Congo-Angola continental margin (West African coast, Equatorial South Atlantic Ocean) represents a unique deep-sea sedimentary ecosystem. It is characterized by high organic matter inputs from the Congo River, that flow along a canyon and through presently active channel system-lifted into the deeper areas (5 000 m) where the lobes system develops.The aim of this thesis is to study the spatial distribution as well as the phylogenetic and functional diversity of archaeal and bacterial communities in relation with environmental characteristics and constraints of the terminal lobes of the Congo deep see fan, one of the largest submarine fan systems in the world.This study highlights geographical distribution of microbial...
Tipo: Text
Palavras-chave: Système turbiditique du Congo; Sédiment riche en matière organique; Communautés microbiennes; Bactéries méthanotrophes aérobies; Suintements de méthane; Methane seeps; Congo turbiditic system; Organic-rich sediment; Microbial communities; Aerobic methane oxidizing bacteria.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00498/60929/64323.pdf