Consulta: creatorFacets:"Guillou, Gael"
Registros recuperados: 10
Data/hora: 05/06/2024 10:23:53

Spatio-temporal variations in intertidal mudflat erodability: Marennes-Oleron Bay, western France
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Orvain, Francis; Sauriau, Pierre-guy; Le Hir, Pierre; Guillou, Gael; Cann, Philippe; Paillard, Michel.
A portable erosion device (ERIS) was deployed in November 2000 and May 2001 to investigate the spatio-temporal variation of fine-grained sediment erosion over a transect on the intertidal mudflats of Marennes-Oleron Bay, western France. The objective was to relate changes in bed erodability over diurnal emersion periods to bioturbation, rapid changes in sediment characteristics, and microphytobenthos biomass.   Macrofaunal assemblages were dominated by the bivalve, Scrobicularia plana, on the upper mudflat, and by the gastropod, Hydrobia ulvae. on the middle mudflat. A power relationship was obtained where tau(cr) was plotted as a function of sediment density. Results from the upper part of the mudflat deviated from this relationship due to bioturbation by...
Tipo: Text
Palavras-chave: EPS; Microphytobenthos; Erodability; Intertidal mudflat; Sediment; Scrobicularia plana; Hydrobia ulvae; Bioturbation; Resuspension; Eris.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3779.pdf

Relative contribution of natural productivity and compound feed to tissue growth in blue shrimp (Litopenaeus stylirostris) reared in biofloc: Assessment by C and N stable isotope ratios and effect on key digestive enzymes
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Cardona, Emilie; Lorgeoux, Benedicte; Geffroy, Claire; Richard, Pierre; Saulnier, Denis; Gueguen, Yannick; Guillou, Gael; Chim, Liet.
The aim of this study was to assess the relative contribution of natural productivity and compound food to the growth of the juvenile blue shrimp Litopenaeus stylirostris reared in a biofloc system. Two experiments were carried out based on the same protocol with three treatments: clear water with experimental diet (CW), biofloc with experimental diet (BF) and biofloc unfed (BU). Shrimp survival was significantly higher in biofloc rearing than in CW rearing. The contribution of the biofloc to shrimp diet was estimated through measurement of carbon and nitrogen stable isotope ratios in shrimp and food sources. Different isotopic compositions between feeds were obtained by feeding natural productivity with a mixture rich in fish meal and the shrimps with a...
Tipo: Text
Palavras-chave: Biofloc; Shrimps; Stable isotope; Digestive enzyme activities; Digestive enzyme mRNA level.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00271/38242/37241.pdf

Dynamics of particulate organic matter composition in coastal systems: a spatio-temporal study at multi-systems scale
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Lienart, Camilla; Savoye, Nicolas; Bozec, Yann; Breton, Elsa; Conan, Pascal; David, Valerie; Feunteun, Eric; Grangere, Karine; Kerherve, Philippe; Lebreton, Benoit; Lefebvre, Sebastien; L'Helguen, Stephane; Mousseau, Laure; Raimbault, Patrick; Richard, Pierre; Riera, Pascal; Sauriau, Pierre-guy; Schaal, Gauthier; Aubert, Fabien; Aubin, Sebastien; Bichon, Sabrina; Boinet, Christophe; Bourasseau, Line; Breret, Martine; Caparros, Jocelyne; Cariou, Thierry; Charlier, Karine; Claquin, Pascal; Cornille, Vincent; Corre, Anne-marie; Costes, Laurence; Crispi, Olivier; Crouvoisier, Muriel; Czamanski, Marie; Del Amo, Yolanda; Derriennic, Herve; Dindinaud, Francois; Durozieri, Maia; Hanquiez, Vincent; Nowaczyk, Antoine; Devesa, Jeremy; Ferreira, Sophie; Fornier, Michel; Garcia, Fabrice; Garcia, Nicole; Geslin, Sandrine; Grossteffan, Emilie; Gueux, Aurore; Guillaudeau, Julien; Guillou, Gael; Joly, Orianne; Lachaussee, Nicolas; Lafont, Michel; Lamoureux, Jezabel; Lecuyer, Eric; Lehodey, Jean-paul; Lemeille, David; Leroux, Cedric; Mace, Eric; Maria, Eric; Pineau, Philippe; Petit, Franck; Pujo-pay, Mireille; Rimelin-maury, Peggy; Sultan, Emmanuelle.
In coastal systems, the multiplicity of sources fueling the pool of particulate organic matter (POM) leads to divergent estimations of POM composition. Eleven systems (two littoral systems, eight embayments and semi-enclosed systems and one estuary) distributed along the three maritime façades of France were studied for two to eight years in order to quantify the relative contribution of organic matter sources to the surface-water POM pool in coastal systems. This study was based on carbon and nitrogen elemental and isotopic ratios, used for running mixing models.  The POM of the estuary is dominated by terrestrial material (93% on average), whereas the POM of the other systems is dominated by phytoplankton (84% on average). Nevertheless, for the latter...
Tipo: Text
Palavras-chave: Particulate organic matter; Coastal systems; C and N stable isotopes; C:N ratio; Mixing model.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00374/48550/48871.pdf

Mercury in blue shark ( Prionace glauca ) and shortfin mako ( Isurus oxyrinchus ) from north-eastern Atlantic: Implication for fishery management
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Biton-porsmoguer, Sebastian; Banaru, Daniela; Boudouresque, Charles F.; Dekeyser, Ivan; Bouchoucha, Marc; Marco-miralles, Francoise; Lebreton, Benoit; Guillou, Gael; Harmelin-vivien, Mireille.
Pelagic sharks (blue shark Prionace glauca and shortfin mako Isurus oxyrinchus) caught by long-line Spanish and Portuguese fleets in the NE Atlantic, were sampled at Vigo fish market (Spain) for total mercury (Hg) analysis. Hg concentration in white muscle increased with size and weight in both species, but at a higher rate in shortfin mako than in the blue shark. No difference was found with sex, year and season. Spatial variation was observed in the blue shark with higher Hg values in the North of the Azorean archipelago, but not in the shortfin mako. These high-level predators are particularly susceptible to bioaccumulate contaminants (Hg) in their tissues (muscle). However, a significant positive relationship between Hg concentration and trophic level...
Tipo: Text
Palavras-chave: Mercury; Pelagic sharks; Blue shark; Shortfin mako; Long-line fishery; NE Atlantic.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00413/52492/56296.pdf

Dynamics and sources of suspended particulate organic matter in the Marennes-Oléron oyster farming bay: Insights from stable isotopes and microalgae ecology
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Malet, Nathalie; Sauriau, Pierre-guy; Ryckaert, Mireille; Malestroit, Pascale; Guillou, Gael.
The aim of this study was to distinguish between sources of the complex variety of Marennes-Oléron Bay suspended particulate organic matter (SPOM) contributing to the tropho-dynamics of the Marennes-Oléron oyster farming bay. Basic biomarkers (Chl a, C/N and POC/Chl a ratios), carbon and nitrogen stable isotopes from SPOM were analyzed and the microalgae community was characterized. The sampling strategy was bimonthly from March 2002 to December 2003; samples were taken from an intertidal mudflat. Four main sources contributed to the SPOM pool: terrigenous input from rivers, neritic phytoplankton, resuspended microphytobenthos and periodic inputs from intertidal Zostera noltii meadows. Seasonal fluctuations were observed in both years of the study period:...
Tipo: Text
Palavras-chave: Heatwave; Zostera noltii; Mudflat; Microphytobenthos; Phytoplankton; Suspended particulate organic matter; Marennes Oléron Bay.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4313.pdf

Trophic importance of diatoms in an intertidal Zostera noltii seagrass bed: Evidence from stable isotope and fatty acid analyses
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Lebreton, Benoit; Richard, Pierre; Galois, Robert; Radenac, Gilles; Pfleger, Camille; Guillou, Gael; Mornet, Francoise; Blanchard, Gerard F.
A current predominant paradigm emphasizes the role of epiphytic algae for invertebrates in most seagrass food webs. However, in some intertidal Zostera noltii beds, epiphyte biomass is very low compared to microphytobenthos and seagrass biomasses. We assessed the role of microphytobenthos in a temperate intertidal Z. noltii bed by combining stable isotope and fatty acid (FA) analyses on primary producers, composite sources suspended particulate organic matter (SPOM) and sediment surface organic matter (SSOM) and the main macrofaunal consumers. Z. noltii showed high delta C-13 (-9.9 parts per thousand) and high 18:2(n-6) and 18:3(n-3) contents. Microphytobenthos was slightly more C-13-depleted (-15.4 parts per thousand) and had high levels of diatom...
Tipo: Text
Palavras-chave: Food web; Intertidal seagrass bed; Microphytobenthos; Zostera noltii; Stable isotope ratio; Fatty acid profiles; European Atlantic coast.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00035/14640/12051.pdf

Macroalgae delta N-15 values in well-mixed estuaries: Indicator of anthropogenic nitrogen input or macroalgae metabolism?
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Raimonet, Melanie; Guillou, Gael; Mornet, Francoise; Richard, Pierre.
Although nitrogen stable isotope ratio (delta N-15) in macroalgae is widely used as a bioindicator of anthropogenic nitrogen inputs to the coastal zone, recent studies suggest the possible role of macroalgae metabolism in delta N-15 variability. Simultaneous determinations of delta N-15 of dissolved inorganic nitrogen (DIN) along the land sea continuum, inter-species variability of delta N-15 and its sensitivity to environmental factors are necessary to confirm the efficiency of macroalgae delta N-15 in monitoring nitrogen origin in mixed-use watersheds. In this study, delta N-15 of annual and perennial macroalgae (Ulva sp., Enterommpha sp., Fucus vesiculosus and Fucus serratus) are compared to delta N-15-DIN along the Charente Estuary, after...
Tipo: Text
Palavras-chave: Nitrogen isotopes; Nitrate; Ammonium; Primary producers; Indicators; Land-sea continuum.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00134/24558/23645.pdf

Food web structure of a Mediterranean coralligeneous ecosystem
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Belloni, Bruno; Sartoretto, Stephane; Cresson, Pierre; Bouchoucha, Marc; Guillou, Gael; Lebreton, Benoit; Ruitton, Sandrine; Harmelin-vivien, Mireille.
The coralligenous ecosystem is one of the biodiversity hotspots in the Mediterranean Sea. This study aims at determining (i) the organic matter (OM) sources at the base of the food web in a coralligenous  ecosystem  near  Marseille  (Cap  Caveau,  Frioul  Island)  and  (ii)  the  global functional structure of its community. For that purpose, C and N stable isotope analyses were performed on 78 compartments or species collected in this habitat between 30 and 40 m depth. Results  suggested  that  the  pelagic  particulate  organic  matter  (POM),  mainly  composed  of phytoplankton, was the main OM source fuelling coralligenous food webs, followed by sedimented organic matter (SOM) and some macrophytes. At least three level of consumers were identified from...
Tipo: Text
Palavras-chave: Food webs; Coralligenous ecosystem; Stable isotopes; Carbon; Nitrogen.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00483/59511/62396.pdf

Dynamics of particulate organic matter composition in coastal systems: forcing of spatio-temporal variability at multi-systems scale
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Lienart, Camilla; Savoye, Nicolas; David, Valerie; Ramond, Pierre; Tress, Paco Rodriguez; Hanquiez, Vincent; Marieu, Vincent; Aubert, Fabien; Aubin, Sebastien; Bichon, Sabrina; Boinet, Christophe; Bourasseau, Line; Bozec, Yann; Breret, Martine; Breton, Elsa; Caparros, Jocelyne; Cariou, Thierry; Claquin, Pascal; Conan, Pascal; Corre, Anne-marie; Costes, Laurence; Crouvoisier, Muriel; Del Amo, Yolanda; Derriennic, Herve; Dindinaud, Francois; Duran, Robert; Durozier, Maia; Devesa, Jeremy; Ferreira, Sophie; Feunteun, Eric; Garcia, Nicole; Geslin, Sandrine; Grossteffan, Emilie; Gueux, Aurore; Guillaudeau, Julien; Guillou, Gael; Jolly, Orianne; Lachaussee, Nicolas; Lafont, Michel; Lagadec, Veronique; Lamoureux, Jezabel; Lauga, Beatrice; Lebreton, Benoit; Lecuyer, Eric; Lehodey, Jean-paul; Leroux, Cedric; L'Helguen, Stephane; Mace, Eric; Maria, Eric; Mousseau, Laure; Nowaczyk, Antoine; Pineau, Philippe; Petit, Franck; Pujo-pay, Mireille; Raimbault, Patrick; Rimmelin-maury, Peggy; Rouaud, Vanessa; Sauriau, Pierre-guy; Sultan, Emmanuelle; Susperregui, Nicolas.
In costal systems, particulate organic matter (POM) results from a multiplicity of sources having their respective dynamics in terms of production, decomposition, transport and burial. The POM pool experiences thus considerable spatial and temporal variability. In order to better understand this variability, the present study employs statistical multivariate analyses to investigate links between POM composition and environmental forcings for a panel of twelve coastal systems distributed along the three maritime regions of France and monitored weekly to monthly for 1 to 8 years. At multi-system scale, two main gradients of POC composition have been identified: a ‘Continent-Ocean’ gradient associated with hydrodynamics, sedimentary dynamics and depth of the...
Tipo: Text
Palavras-chave: Particulate organic matter; Coastal systems; Environmental forcing; Meta-analysis; France.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00433/54471/55848.pdf

Effect of seasonal variation in trophic conditions and the gametogenic cycle on d13C and d15N levels of diploid and triploid Pacific oysters Crassostrea gigas
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Malet, Nathalie; Sauriau, Pierre-guy; Faury, Nicole; Soletchnik, Patrick; Guillou, Gael.
Carbon and nitrogen stable isotopes were investigated in separate organs of diploid and sterile triploid Pacific oysters Crassostrea gigas for 13 mo, together with changes in chemical and isotope composition of suspended matter sampled from an intertidal mudflat within Marennes-Oléron Bay, France. Particulate organic matter (POM) was a mixture of pelagic and benthic material with a predominance of neritic phytoplankton in spring, and resuspended microphytobenthos in summer and autumn. A remarkable shift of +30/00 in d13C was reflected in both diploids and triploids from spring to summer, and further temporal differences were observed amongst their tissues. Seasonal changes in POM d15N were also reflected in oyster tissues, with digestive gland and muscle...
Tipo: Text
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2828.pdf