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| Registros recuperados: 15 | |
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| Gasmi, Sonia; Bernard, Ismael; Pouvreau, Stephane; Maurer, Daniele; Schaal, Gauthier; Ganthy, Florian; Cominassi, Louise; Allain, Gwenhael; Sautour, Benoit; David, Valerie. |
| In macrotidal coastal ecosystems, spatial heterogeneity of the water column properties is induced by both oceanic and continental influences. Hydrodynamic processes generate a land-sea gradient of environmental conditions, affecting the biological performances of sedentary organisms. The aim of the present study is to establish an extensive spatial assessment in the reproductive investment of the wild Pacific oyster Crassostrea gigas in Arcachon Bay. This is done by looking for a relationship between the Lawrence and Scott condition index (LSCI) and two tidal processes: the immersion level (IL) and the local oceanic flushing time (LoFt). The LSCI of C. gigas was assessed, just before gamete release, at 68 sampling stations in Arcachon Bay. Oyster... |
| Tipo: Text |
Palavras-chave: Reproductive investment; Crassostrea gigas; Macrotidal lagoon; Immersion level; Oceanic flushing; Environmental variability. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00357/46803/46670.pdf |
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| Mathieu-resuge, Margaux; Schaal, Gauthier; Kraffe, Edouard; Corvaisier, Rudolph; Lebeau, Oanez; Lluch-cota, Salvador E.; Salgado García, Rosa L.; Kainz, Martin J.; Le Grand, Fabienne. |
| The trophic fate of various food sources is of central interest for ecologists, yet not well understood in coastal lagoon food webs. In this field study, fatty acids (FA), stable isotopes (SI), and compound-specific isotopic analysis (CSIA) on FA were used to investigate how diets from oceanic and local sources are retained in a bivalve species (Spondylus crassisquama; Lamarck 1819) along a transect in the Ojo de Liebre lagoon (BCS, Mexico). Results from SI and FA indicated the contribution of oceanic diatoms at the entrance of the lagoon, through 15N enrichment, and higher proportions of 16:1n-7 and 20:5n-3 in digestive glands. In the inner bay, higher abundance of 18-carbon FA (18:1n-9, 18:3n-3, 18:4n-3) suggested a higher contribution of... |
| Tipo: Text |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00501/61306/64914.pdf |
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| Le Croizier, Gaël; Lorrain, Anne; Schaal, Gauthier; Ketchum, James; Hoyos-padilla, Mauricio; Besnard, Lucien; Munaron, Jean-marie; Le Loch, Francois; Point, David. |
| Worldwide shark populations have experienced rapid declines over the last decades, mainly due to overfishing. Marine protected areas (MPAs) have thus become an indispensable tool for the protection of these marine predators. Two recently-created MPAs in the Northeast Pacific Ocean, the Revillagigedo National Park and Clipperton atoll, are characterized by different trophic structures potentially influencing trophic niche and contaminant exposure for resident sharks in these two sites. In this context, we used carbon (δ13C) and nitrogen (δ15N) stable isotope analyzes as well as total mercury concentrations ([THg]) to assess the role of foraging site on the trophic niche and Hg levels of juvenile ST sharks Carcharhinus albimarginatus. Analyzing fin clip... |
| Tipo: Text |
Palavras-chave: Top-predators; Mercury transfer; Food webs; Foraging habitat; Stable isotopes; MPAs. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00619/73114/72257.pdf |
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| Le Croizier, Gaël; Lorrain, Anne; Sonke, Jeroen E.; Jaquemet, Sébastien; Schaal, Gauthier; Renedo, Marina; Besnard, Lucien; Cherel, Yves; Point, David. |
| In coastal ecosystems, top predators are exposed to a wide variety of nutrient and contaminant sources due to the diversity of trophic webs within coastal areas. Mercury contamination could represent an additional threat to shark populations that are declining worldwide. Here we measured total mercury, carbon and nitrogen isotopes as well as mercury isotopes in two co-occurring shark species (the bull shark Carcharhinus leucas and the tiger shark Galeocerdo cuvier) and their prey from a coastal ecosystem of the western Indian Ocean (La Réunion Island), to (i) determine their main trophic Hg source and (ii) better characterize their diet composition and foraging habitat. Hg isotope signatures (Δ199Hg and δ202Hg) of shark prey suggested that bull sharks were... |
| Tipo: Text |
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| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00633/74465/74289.pdf |
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| 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 |
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| Hochard, Sebastien; Ducrocq, Manuel; Lemonnier, Hugues; Royer, Florence; Hubert, Morgane; Michaut, Henri; Verge, Raphael; Letourneur, Yves; Lorrain, Anne; Mathieu-resuge, Margaux; Schaal, Gauthier; Kraffe, Edouard; Legrand, Fabienne; Burgy, Laurent; Kuhn, John; Kuhn, Sandra; Queffelec, Laurent; Millot, Maxime; Le Rohellec, Julien; Benoit, Julie; Vanhuysse, Charles. |
| Tipo: Text |
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| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00347/45798/45444.pdf |
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| Le Croizier, Gael; Schaal, Gauthier; Point, David; Le Loc'H, Francois; Machu, Eric; Fall, Massal; Munaron, Jean-marie; Boye, Aurelien; Walter, Pierre; Lae, Raymond; De Morais, Luis Tito. |
| Bioaccumulation of toxic metal elements including mercury (Hg) can be highly variable in marine fish species. Metal concentration is influenced by various species-specific physiological and ecological traits, including individual diet composition and foraging habitat. The impact of trophic ecology and habitat preference on Hg accumulation was analyzed through total Hg concentration and stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) analyses in the muscle of 132 fish belonging to 23 different species from the Senegalese coast (West Africa), where the marine ecosystem is submitted to nutrients inputs from various sources such as upwelling or rivers. Species-specific ecological traits were first investigated and results showed that vertical (i.e.... |
| Tipo: Text |
Palavras-chave: Methylmercury sources; Trophic ecology; Feeding habitat; Metal bioaccumulation; Chemical tracers; Isotopic niche. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00458/57013/58912.pdf |
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| Burel, Thomas; Schaal, Gauthier; Grall, Jacques; Le Duff, Michel; Chapalain, Georges; Schmitt, Blondie; Gemin, Maxence; Boucher, Olivier; Ar Gall, Erwan. |
| Wave height was used as a proxy to assess the effect of hydrodynamics on the development and structure of intertidal North-East Atlantic rocky macroalgal communities (Brittany). The characterization of hydrodynamics at small-scale (about 10 m) was performed through wave height in situ monitoring using pressure sensors. Both the diversity and the cover of the macroalgal communities were sampled in parallel. Wave heights exhibit large variations with values ranging from ca. 5 cm to 1.60 m. We show that wave height directly controls the cover of macroalgal canopies (Pearson's r between −0.62 and −0.39). In all communities, most of the fucoid covers regressed with increasing wave height values. By contrast, positive correlations were found at low shore levels... |
| Tipo: Text |
Palavras-chave: Macroalgal communities; Intertidal zone; Rocky shores; Wave heights; Hydrodynamics; Mini-diver; Brittany. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00506/61769/65752.pdf |
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| Schaal, Gauthier; Nerot, Caroline; Grall, Jacques; Chouvelon, Tiphaine; Lorrain, Anne; Mortillaro, Jean-michel; Savoye, Nicolas; Brind'Amour, Anik; Paulet, Yves-marie; Le Bris, Herve. |
| Although stable isotope ratios are increasingly used to investigate the trophic ecology of marine organisms, their spatial variations are still poorly understood in the coastal environment. In this study, we measured the stable isotope composition (δ13C, δ15N) of suspended particulate organic matter (SPOM) (primary producer), a suspension feeder, the great scallop Pecten maximus (primary consumer), megabenthic decapods and benthic fishes (secondary consumers) along a depth gradient (from 5m to 155m depth) across the continental shelf of the Bay of Biscay. Although the three trophic levels exhibited similar δ13C patterns along the gradient, the δ15N patterns varied between SPOM, scallops and carnivores. The δ15N difference between SPOM and scallops... |
| Tipo: Text |
Palavras-chave: Trophic; Coastal; Bivalves; Food web; Bay of Biscay. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00288/39921/38481.pdf |
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| Mathieu-resuge, Margaux; Kraffe, Edouard; Le Grand, Fabienne; Boens, Andy; Bideau, Antoine; Lluch-cota, Salvador E.; Racotta, Ilie S.; Schaal, Gauthier. |
| Understanding the nature and origins of food sources supporting coastal lagoon-inhabiting organisms is necessary to evaluate the ecological status of such ecosystems. The trophic ecology of a bivalve specie Spondylus crassisquama was studied in the Ojo de Liebre lagoon (Baja California, Mexico), combining stable isotope (SI), fatty acid (FA) and sterols analyses along a transect under oceanic influences. The second objective of the study was to investigate if sterols compositions give complementary information to those obtained from FA and SI. Temporal and spatial patterns of the three biomarkers in bivalve tissues suggest oceanic inputs at the mouth of the lagoon, while the inner station was characterized by a contribution of local sources including an... |
| Tipo: Text |
Palavras-chave: Coastal zone; Ojo de liebre; Suspension-feeders; Multi-tracer analyses; Fatty acids; Stables isotopes; Sterols. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00484/59521/62494.pdf |
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| Mathieu-resuge, Margaux; Le Grand, Fabienne; Schaal, Gauthier; Kraffe, Edouard; Lorrain, Anne; Letourneur, Yves; Lemonnier, Hugues; Benoît, Julie; Hochard, Sébastien. |
| Deposit-feeding sea cucumbers are efficient nutrient recyclers and have the potential to contribute to the limitation of organic matter load in polyculture or integrated aquaculture systems. Assessing how they assimilate organic matter originating from other farmed species is therefore important for the development of such multi-species farming systems. Here, a coupled stable isotope − fatty acid approach was used to characterize the assimilation of organic matter from shrimp (Penaeus stylirostris) farming by Holothuria scabra in an experimental culture system. H. scabra were reared in mesocosms on shrimp farming-originating sediment with and without additional food sources (maize and fish meals). Although fatty acid results did indicate that... |
| Tipo: Text |
Palavras-chave: Fatty acids; Stable isotopes; Rotational co-culture; Shrimp-farming; Holothurid. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00624/73589/73023.pdf |
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| Lelievre, Yann; Sarrazin, Jozee; Marticorena, Julien; Schaal, Gauthier; Day, Thomas; Legendre, Pierre; Hourdez, Stephane; Matabos, Marjolaine. |
| Hydrothermal vent sites along the Juan de Fuca Ridge in the north-east Pacific host dense populations of Ridgeia piscesae tubeworms that promote habitat heterogeneity and local diversity. A detailed description of the biodiversity and community structure is needed to help understand the ecological processes that underlie the distribution and dynamics of deep-sea vent communities. Here, we assessed the composition, abundance, diversity and trophic structure of six tubeworm samples, corresponding to different successional stages, collected on the Grotto hydrothermal edifice (Main Endeavour Field, Juan de Fuca Ridge) at 2196 m depth. Including R. piscesae, a total of 36 macrofaunal taxa were identified to the species level. Although polychaetes made up the... |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00439/55083/56515.pdf |
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| Le Croizier, Gael; Schaal, Gauthier; Gallon, Regis; Fall, Massal; Le Grand, Fabienne; Munaron, Jean-marie; Rouget, Marie-laure; Machu, Eric; Le Loc'H, Francois; Lae, Raymond; De Morais, Luis Tito. |
| The link between trophic ecology and metal accumulation in marine fish species was investigated through a multi-tracers approach combining fatty acid (FA) and stable isotope (SI) analyses on fish from two contrasted sites on the coast of Senegal, one subjected to anthropogenic metal effluents and another one less impacted. The concentrations of thirteen trace metal elements (As, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Sn, U, and Zn) were measured in fish liver. Individuals from each site were classified into three distinct groups according to their liver FA and muscle SI compositions. Trace element concentrations were tested between groups revealing that bioaccumulation of several metals was clearly dependent on the trophic guild of fish. Furthermore,... |
| Tipo: Text |
Palavras-chave: Trace elements; Biochemical tracers; Diet; Contamination; Senegal; Tropical fish. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00348/45908/45707.pdf |
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| Mathieu-resuge, Margaux; Le Grand, Fabienne; Schaal, Gauthier; Lluch-cota, Salvador E; Racotta, Ilie S; Kraffe, Edouard; Todgham, Anne. |
| Bivalves’ physiological functions (i.e. growth, reproduction) are influenced by environmental variability that can be concomitant with trophic resource variations in terms of quality and quantity. Among the essential molecules that bivalves need to acquire from their diet to maintain physiological functions, fatty acids (FAs) such as polyunsaturated fatty acids (e.g. 20:4n-6 (arachidonic acid), 20:5n-3 (eicosapentaenoic acid) and 22:6n-3 (docosahexaenoic acid)) have been described to play a critical role. The present study examined the FA composition of gill membrane lipids of two bivalve species, Nodipecten subnodosus and Spondylus crassisquama, sampled in a coastal lagoon of the Northeastern Pacific (Ojo de Liebre, Mexico), at two contrasting locations... |
| Tipo: Text |
Palavras-chave: Bivalves; Coastal lagoon; Gill membrane fatty acids; Diet influence; Physiological regulation; Trophic ecophysiology. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00648/75991/76893.pdf |
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| Registros recuperados: 15 | |
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