|
|
|
| Registros recuperados: 38 | |
|
|
| Kopp, Dorothee; Lefebvre, Sebastien; Villanueva, Ching-maria; Ernande, Bruno. |
| The structure, dynamics and productivity of marine ecosystems depend mainly on their underlying food webs. In temperate marine ecosystems, specifically in the English Channel, strong seasonality, habitat diversity and variability in the sources of available organic matters are controlling factors affecting the trophodynamics of these networks. Exploitation through fisheries may also alter these food webs. During the last decade, the study of trophic ecology has greatly benefited from the use of stable isotope analysis (SIA) that integrates diet information over long time periods and complements gut content analysis. Applied in complex ecosystems, such as the English Channel, SIA may help to detect nutrient pathways and trophic links. Stable isotopic... |
| Tipo: Text |
|
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00161/27213/25412.pdf |
| |
|
|
| Emmery, Antoine; Lefebvre, Sebastien; Alunno-bruscia, Marianne; Kooijman, S. A. L. M.. |
| We studied the dynamics of stable isotopes δ13C and δ15N of an opportunistic suspension feeder the Pacific oyster (Crassostrea gigas) to better understand the factors that influence the trophic enrichment (trophic-shift, Δ) between primary producers and consumers. Most of the previous studies on this topic do not quantify mass fluxes or isotopic discrimination phenomena in the organism, which are two pillars in isotope ecology. We used a dynamic energy budget (DEB) approach (Kooijman, 2010) to quantify i) the fluxes of elements and isotopes in C. gigas soft tissues and ii) the impact of the scaled feeding level, the organism mass and the isotopic ratio of food on the "trophic-shift" Δ, and isotope turnover in tissues. Calibration and parametrization... |
| Tipo: Text |
Palavras-chave: Oyster; Isotopic ratio; Discrimination; Trophic-shift; Diet; DEB theory. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00043/15434/12784.pdf |
| |
|
|
| Majdi, Nabil; Hette-tronquart, Nicolas; Auclair, Etienne; Bec, Alexandre; Chouvelon, Tiphaine; Cognie, Bruno; Danger, Michael; Decottignies, Priscilla; Dessier, Aurélie; Desvilettes, Christian; Dubois, Stanislas; Dupuy, Christine; Fritsch, Clémentine; Gaucherel, Cédric; Hedde, Mickaël; Jabot, Franck; Lefebvre, Sebastien; Marzloff, Martin; Pey, Benjamin; Peyrard, Nathalie; Powolny, Thibaut; Sabbadin, Régis; Thébault, Elisa; Perga, Marie-elodie. |
| Trophic ecology is the study of feeding interactions and food acquisition by organisms. It includes the causes and consequences of those behaviours at all levels of biological organisation. As a field of research, it crosses many disciplinary boundaries and provides knowledge that is pertinent to many other areas of ecology. Here we list and categorise the methods available to trophic ecologists whose toolbox has broadened considerably in recent years. They encompass empirical and numerical approaches with focus ranging from molecules to ecosystems. We further examine the relationship of each method to features such as the scale of observation (from microbes to largest organisms) and organisational level (from individuals to ecosystems) as well as the... |
| Tipo: Text |
Palavras-chave: Food web; Feeding interactions; Flux of energy; Computer simulations; Trophic models. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00487/59834/65986.pdf |
| |
|
|
| Lopes Galasso, Helena; Richard, Marion; Lefebvre, Sebastien; Aliaume, Catherine; Callier, Myriam. |
| Considering the ecological importance and potential value of Hediste diversicolor, a better understanding of its metabolic rate and potential growth rates is required. The aims of this study are: (i) to describe key biometric relationships; (ii) to test the effects of temperature and body size on standard metabolic rate (as measure by oxygen consumption) to determine critical parameters, namely Arrhenius temperature (TA), allometric coefficient (b) and reaction rate; and (iii) to determine the metabolic scope for activity (MSA) of H. diversicolor for further comparison with published specific growth rates. Individuals were collected in a Mediterranean lagoon (France). After 10 days of acclimatization, 7 days at a fixed temperature and 24 h of fasting,... |
| Tipo: Text |
Palavras-chave: Annelida; Deposit-feeder; Oxygen consumption; Allometric coefficient; Arrhenius temperature; Aerobic scope; Growth. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00465/57682/59885.pdf |
| |
|
|
| Callier, Myriam; Lefebvre, Sebastien; Dunagan, Mary K.; Bataille, Marie-paule; Coughlan, Jennifer; Crowe, Tasman P.. |
| The extent of the influence of salmon farming on the environment and on the uptake of particulate and dissolved effluents by benthic organisms was assessed using community structure and stable isotope analyses. Sediment cores were collected in 2 directions: perpendicular and parallel to the main residual current, 0, 25 and 200 m from 2 salmon farms (Millstone and Cranford) located in Mulroy Bay, Ireland. In addition, artificial substrates were placed for 2 mo at 1 m depth 0, 25 and 200 m from one farm to trace the uptake of farm-related nutrients by fouling organisms. The extent of measurable change in benthic communities (abundance, diversity, structure, trophic composition) depended on residual current direction. Intraspecific variation in isotopic... |
| Tipo: Text |
Palavras-chave: Aquaculture; Organic matter; Stable isotope; Community structure; Diet shift; Trophic structure. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00144/25481/23634.pdf |
| |
|
| |
|
|
| Cresson, Pierre; Travers-trolet, Morgane; Rouquette, Manuel; Timmerman, Charles-andre; Giraldo, Carolina; Lefebvre, Sebastien; Ernande, Bruno. |
| Whether considered as a risk for human health or as ecological tracers, contaminants' concentrations measured in fish muscles are commonly expressed relative to wet or dry mass. Comparison of results required conversion factors (CF) but accurate values are scarce and case-specific. The present paper is aimed at investigating errors linked with the use of the theoretical value. Muscles dry and wet masses were measured in 15 fish species to determine the actual CF. Most CF were lower than the theoretical wet:dry ratio of 5 classically used, with variations at individual and species level. Muscle lipid content (inferred by C/N ratios) was a crucial factor explaining discrepancies, claiming for caution when working with lipid-rich species. The observed... |
| Tipo: Text |
Palavras-chave: Wet:dry ratio; Conversion factor; Contaminant concentration; Marine fish; Percentage of humidity. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00396/50736/51456.pdf |
| |
|
|
| De Cubber, Lola; Lefebvre, Sebastien; Fisseau, Charline; Cornille, Vincent; Gaudron, Sylvie Marylene. |
| Arenicola spp. are marine benthic polychaetes dug for bait by anglers. Without regulation, this activity can lead to the decrease of lugworms' population meanwhile affecting the physical characteristics of the beach and the biodiversity. Here, we identified through morphology and genetics two species of lugworms, Arenicola marina and A. defodiens, within a Marine Protected Area of the Eastern English Channel (France). For each species, abundance and spatial distribution were assessed using a stratified random sampling and interpolation at four studied sites, as well as some life-history traits. These data were compared to lugworms' collection data to estimate its sustainability and to provide potential management measures. At one site, A. marina was... |
| Tipo: Text |
Palavras-chave: Arenicola marina; Arenicola defodiens; Spawning; Population structure; Size at first maturity; Recreational fisheries; Conservation; English channel. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00451/56284/60474.pdf |
| |
|
| |
|
|
| Hussenot, Jerome; Lefebvre, Sebastien; Martin, Jean-louis. |
| Fish culture (seabass, turbot...) on the French metropolitan coast, and shrimp culture in the overseas territories (essentially New Caledonia and Tahiti) are subject to a regular development through land based farms. Three thematic of research on aquaculture ponds are carried out in CREMA-L’Houmeau, in collaboration with producers. The aim of the first one is to determine the optimal rearing conditions (stocking density, water renewal rate, input of oxygen, rate of feeding...) which allow to minimise the quantity of wastes for a similar final biomass. The second part aims to reduce the nutrient loading in the effluent, through open-air treatments: sedimentation ponds, foam fractionation, mass production of phytoplankton, and rearing of molluscs on the... |
| Tipo: Text |
Palavras-chave: Fish; Shrimp; Pond management; Effluents; Treatment. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00016/12728/9650.pdf |
| |
|
|
| Houliez, Emilie; Lefebvre, Sebastien; Lizon, Fabrice; Schmitt, Francois G.. |
| This study is the first in situ work comparing rapid light curves (RLC) and non-sequential steady-state light curves (N-SSLC) in their efficiency to characterize phytoplankton photosynthetic activity and acclimation status. Measurements were carried out at two time scales (daily and annual) using the Pulse Amplitude Modulated fluorometry on samples taken in the coastal waters of a macrotidal ecosystem (the Strait of Dover, eastern English Channel). RLC and N-SSLC were compared under a wide range of environmental conditions and phytoplankton composition in order to define the best methodology to accurately capture short and long-term adjustments in the functioning of the photosynthetic apparatus. The relationships between the photosynthetic parameters... |
| Tipo: Text |
|
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00395/50596/51484.pdf |
| |
|
| |
|
|
| Emmery, Antoine; Lefebvre, Sebastien; Alunno-bruscia, Marianne; Kooijman, S. A. L. M.. |
| Biological performances (growth and reproduction) of intertidal bivalves mainly rely on environmental factors such as water temperature and food sources. Both quality and quantity of bivalve food sources, however, are not easy to determine because of complex features of coastal ecosystem functioning, such as high spatial heterogeneity. This is particularly critical for oyster (Crassostrea gigas) culture in France when quantifying and explaining the variability in growth performances of oysters among culture sites at a large spatial scale. In this context, insights for new operational tools to characterise trophic features of coastal ecosystems are needed. The aim of the present study is to couple natural isotope tracers and DEB modeling to describe and... |
| Tipo: Text |
|
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00032/14370/11659.pdf |
| |
|
|
| Chouvelon, Tiphaine; Chappuis, A.; Bustamante, Paco; Lefebvre, Sebastien; Mornet, Francoise; Guillou, G.; Violamer, L.; Dupuy, Christine. |
| European sardine (Sardina pilchardus) and European anchovy (Engraulis encrasicolus) are two species of economical and ecological significance in the Bay of Biscay (north-east Atlantic). However, the trophic ecology of both species is still poorly known in the area, and more generally, few studies have considered the potential trophic overlap between sardines and anchovies worldwide. This study aims to highlight the trophic links between the mesozooplankton and adults of these two pelagic fish in the Bay of Biscay, through carbon and nitrogen stable isotope analysis (SIA). Mesozooplankton and individuals of sardines and anchovies were collected during one season (spring 2010), over spatially contrasted stations within the study area. First, the potential... |
| Tipo: Text |
Palavras-chave: Plankton preservation; Plankton delipidation; Pelagic fish; Trophic interactions; Spatial variability; Isotopic mixing model. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00176/28741/27280.pdf |
| |
|
|
| Lefebvre, Sebastien; Giraldo, Carolina; Kopp, Dorothee; Cresson, Pierre; Travers-trolet, Morgane; Ernande, Bruno. |
| Trophic relationships play a crucial role in shaping community structure and ecological functions in marine ecosystems. Studying food-web variation along environmental gradients is still in its infancy and provides new insights in understanding how abiotic variables shape species interactions. In epicontinental seas, benthic-pelagic couplings modify predator-prey relationships and lead to entangled trophic networks. Here, we assumed that depth affects benthic-pelagic couplings’ strength and we investigated depth-related changes in the feeding patterns of fish in the whole English Channel (EC) used as a case study. Gut content and stable carbon and nitrogen isotopes of 33 fish species were collected between 5-100 m depth in 2009 and in 2014. Samples from... |
| Tipo: Text |
|
| Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00455/56634/58370.pdf |
| |
|
|
| Ubertini, Martin; Lefebvre, Sebastien; Gangnery, Aline; Grangere, Karine; Le Gendre, Romain; Orvain, Francis. |
| The high degree of physical factors in intertidal estuarine ecosystem increases material processing between benthic and pelagic compartments. In these ecosystems, microphytobenthos resuspension is a major phenomenon since its contribution to higher trophic levels can be highly significant. Understanding the sediment and associated microphytobenthos resuspension and its fate in the water column is indispensable for measuring the food available to benthic and pelagic food webs. To identify and hierarchize the physical/biological factors potentially involved in MPB resuspension, the entire intertidal area and surrounding water column of an estuarine ecosystem, the Bay des Veys, was sampled during ebb tide. A wide range of physical parameters (hydrodynamic... |
| Tipo: Text |
|
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00090/20126/17775.pdf |
| |
|
|
| Chambord, Sophie; Villanueva, Ching-maria; Ernande, Bruno; Lefebvre, Sebastien. |
| Les réseaux trophiques engendrent tous les transferts d’énergies et de matières au sein d’un écosystème, ce qui expliquent l’intérêt de leur compréhension. Ces réseaux dépendent essentiellement des relations proies-prédateurs, il est donc important de connaître les processus les déterminants. La morphométrie peut être un processus déterminants les relations proies-prédateurs. Ces travaux ont permis d’identifier les relations entre les caractéristiques morphologiques des individus et leur régime alimentaire chez deux espèces relativement contrastée en termes de guilde trophique, à savoir Pleuronectes platessa (plie, Linné 1758) et Dicentrarchus labrax (bar commun, Linné 1758). |
| Tipo: Text |
|
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00143/25417/23568.pdf |
| |
|
|
| Perga, Marie-elodie; Danger, Michael; Dubois, Stanislas; Fritch, Clementine; Gaucherel, Cedric; Hubas, Cedric; Jabot, Franck; Lacroix, Gerard; Lefebvre, Sebastien; Marmonier, Pierre; Bec, Alexandre. |
| The French National Institute of Ecology and Environment (INEE) aims at fostering pluridisciplinarity in Environmental Science and, for that purpose, funds ex muros research groups (GDR) on thematic topics. Trophic ecology has been identified as a scientific field in ecology that would greatly benefit from such networking activity, as being profoundly scattered. This has motivated the seeding of a GDR, entitled “GRET”. The contours of the GRET's action, and its ability to fill these gaps within trophic ecology at the French national scale, will depend on the causes of this relative scattering. This study relied on a nationally broadcasted poll aiming at characterizing the field of trophic ecology in France. Amongst all the unique individuals that fulfilled... |
| Tipo: Text |
Palavras-chave: Trans-ecosystem; Scientific network; Cleavage; Ecology; Population; Community. |
| Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00442/55338/56849.pdf |
| |
|
|
| 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 |
| |
|
|
| Sangare, Nathanael; Lo-yat, Alain; Le Moullac, Gilles; Pecquerie, Laure; Thomas, Yoann; Lefebvre, Sebastien; Le Gendre, Romain; Beliaeff, Benoit; Andréfouët, Serge. |
| The black-lipped pearl oyster (Pinctada margaritifera) is extensively farmed in French Polynesia to produce black pearls. For a sustainable management of marine resources, studying interactions between organisms and environment, and the associated factors and processes that will impact their life cycle and thus modulate population dynamics is a major research priority. Here, we describe black-lipped pearl oyster energy acquisition and use, and its control by temperature and food concentration within the Dynamic Energy Budget (DEB) theory framework. The model parametrization was based on literature data and a specific laboratory experiment. Model validation was carried out thanks to historical in-situ datasets and a dedicated field survey. Three theoretical... |
| Tipo: Text |
Palavras-chave: Bivalve; Physiology; Bioenergetics; Dynamic energy budget theory; Environmental change; Pearl farming. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00613/72469/71614.pdf |
| |
| Registros recuperados: 38 | |
|
|
|
