Consulta: creatorFacets:"Paulet, Yves-marie"
Registros recuperados: 13
Data/hora: 07/06/2024 03:13:22

The Impossible Sustainability of the Bay of Brest? Fifty Years of Ecosystem Changes, Interdisciplinary Knowledge Construction and Key Questions at the Science-Policy-Community Interface
Provedor de dados: 5
Autores: Ragueneau, Olivier; Raimonet, Melanie; Maze, Camille; Coston-guarini, Jennifer; Chauvaud, Laurent; Danto, Anatole; Grall, Jacques; Jean, Frederic; Paulet, Yves-marie; Thouzeau, Gerard.
In this contribution, the study of the Bay of Brest ecosystem changes over the past 50 years is used to explore the construction of interdisciplinary knowledge and raise key questions that now need to be tackled at the science-policy-communities interface. The Bay of Brest is subject to a combination of several aspects of global change, including excessive nutrient inputs from watersheds and the proliferation of invasive species. These perturbations strongly interact, affecting positively or negatively the ecosystem functioning, with important impacts on human activities. We first relate a cascade of events over these five decades, linking farming activities, nitrogen, and silicon biogeochemical cycles, hydrodynamics of the Bay, the proliferation of an...
Tipo: Text
Palavras-chave: Sustainability; Land-ocean continuum; Bay of Brest; Interdisciplinarity; Science-policy-community interface.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00616/72792/72272.pdf

Experimental shift in diet Delta13C: A potential tool for ecophysiological studies in marine bivalves
Provedor de dados: 5
Autores: Paulet, Yves-marie; Lorrain, Anne; Richard, Joëlle; Pouvreau, Stephane.
To test the potential of diet switching experiments in ecophysiological studies of marine invertebrates, stable carbon isotope ratios were measured at different seasons in the gonad, adductor muscle, digestive gland and gills of scallops (Pecten maximus) and oysters (Crassostrea gigas) held for 15 days on a constant diet of phytoplankton depleted in 13C. The aim of this study was to determine if differences in carbon incorporation could be detected among species, seasons and organs, and if so, whether it was consistent with their known energy-allocation patterns. After offering the new diet, isotope values of the different organs gradually shifted and significant differences among organs, seasons and species were found. A carbon incorporation index (CII)...
Tipo: Text
Palavras-chave: Crassostrea gigas; Pecten maximus; Carbon isotopes; Metabolism; Energy allocation.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1202.pdf

Growth anomalies in Pecten maximus from coastal waters (Bay of Brest, France): relationship with diatom blooms
Provedor de dados: 5
Autores: Lorrain, Anne; Paulet, Yves-marie; Chauvaud, Laurent; Savoye, Nicolas; Nezan, Elisabeth; Guerin, Laurent.
The aim of this study was to characterize the daily shell growth of Pecten maximus from early 1998 to late spring 1999 in the Bay of Brest with a careful qualitative and quantitative description of the pelagic primary production. Our results, in accordance with previous studies, demonstrate that there are episodic declines in the growth rate. Concurrent events of low growth rate and large bottom-concentrations of algae following diatom blooms (Cerataulina pelagica or Rhizosolenia delicatula), suggests that this high concentration of phytoplankton on the bottom layer may affect food intake or respiratory activity of the scallops by gill clogging or oxygen depletion. In this study, silicic acid or phosphorus are inferred to be limiting factors responsible...
Tipo: Text
Palavras-chave: Biscay bay; Limiting factors; Primary production; Phytoplankton cnoncentration; Pecten maximus; Growth rate.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-612.pdf

A multidisciplinary approach to the spatial dimension in ecosystem-based fisheries management
Provedor de dados: 5
Autores: Le Floc'H, Pascal; Bertignac, Michel; Curtil, Olivier; Macher, Claire; Mariat-roy, Emilie; Paulet, Yves-marie.
This study considers how to reconcile different spatial scales to find the best common denominator to be used as an ecosystem-based management unit. For this, two fishery production zones differing ecologically, economically, legally and institutionally were investigated. The first case study is located within French territorial waters, in a MPA created in 2007- the Parc Naturel Marin d'Iroise (PNMI). The second case study, the Bay of Biscay, covers both territorial waters and the French exclusive economic zone. The paper adopts a multidisciplinary approach. Relevant questions concern how marine space is shared between exploited species and fishing fleets, especially the spatial mobility strategies they employ. An assessment of the institutional system...
Tipo: Text
Palavras-chave: Spatial scale; Ecosystem-based fisheries management; Marine protected area; Socio-system.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00460/57191/59156.pdf

Compound-specific recording of gadolinium pollution in coastal waters by great scallops
Provedor de dados: 5
Autores: Le Goff, Samuel; Barrat, Jean-alix; Chauvaud, Laurent; Paulet, Yves-marie; Gueguen, Bleuenn; Ben Salem, Douraied.
Gadolinium-based contrast agents (GBCAs), routinely used in magnetic resonance imaging (MRI), end up directly in coastal seawaters where gadolinium concentrations are now increasing. Because many aquatic species could be sensitive to this new pollution, we have evaluated the possibility of using shellfish to assess its importance. Gadolinium excesses recorded by scallop shells collected in Bay of Brest (Brittany, France) for more than 30 years do not reflect the overall consumption in GBCAs, but are largely controlled by one of them, the gadopentetate dimeglumine. Although its use has been greatly reduced in Europe over the last ten years, gadolinium excesses are still measured in shells. Thus, some gadolinium derived from other GBCAs is bioavailable and...
Tipo: Text
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00615/72758/72029.pdf

Experimental shift of diet and DIC stable carbon isotopes: Influence on shell delta C-13 values in the Manila clam Ruditapes philippinarum
Provedor de dados: 5
Autores: Poulain, C.; Lorrain, Anne; Mas, R.; Gillikin, D. P.; Dehairs, F.; Robert, Rene; Paulet, Yves-marie.
The influences of diet and seawater dissolved inorganic carbon (DIC) on the carbon isotope composition of shell aragonite (Cinched in the Manila clam Ruditapes philippinarum reared under laboratory conditions were investigated. Clams were exposed to two successive negative carbon isotope shifts: a first shift in diet (delta C-13(phytoplankton)) and a second shift, 35 days later, in DIC (delta C-13(DIC)). Both successive shifts induced a decrease in delta C-13(shell). These results are the first to experimentally confirm an incorporation of respired carbon derived from food and carbon from DIC into shell carbonate of adult bivalves. Skeletal delta C-13 responded to changes in the delta C-13 of both diet and DIC in less than 7 days. Consequently, proxies...
Tipo: Text
Palavras-chave: Delta C-13(shell); DIC; Salinity; Metabolic carbon; Ruditapes philippinarum; Estuarine water; Proxy.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00003/11443/8001.pdf

Réalisation d'un modèle de dispersion d'un rejet de dragage et des contaminants associés. Rapport définitif: contrat « LITEAU » 2ème phase
Provedor de dados: 5
Autores: Alzieu, Claude; Andral, Bruno; Bassoullet, Philippe; Boutier, Bernard; Gonzalez, Jean-louis; Huet, Martial; Jestin, Herve; L'Yavanc, Jacky; Michel, Pierre; Paulet, Yves-marie; Quiniou, Francoise; Silva Jacinto, Ricardo.
Le projet à pour but de modéliser la dispersion des immersions des boues de dragage, à partir de modèles numériques de manière à pouvoir évaluer le devenir de la charge particulaire et des contaminants associés. Les résultats des expérimentations en laboratoire montrent, qu'à l'échelle représentative du temps de séjour des particules dans la colonne d'eau du champ proche (quelques heures), on ne constate pas de solubilisation des métaux. La libération de la fraction associée aux eaux interstitielles et les flux à l'interface eau-sédiment (diagenèse précoce) après dépôt des sédiments rejetés, sont les processus qui pourraient être la cause d'un apport important de Cd (ou autre contaminant) dissous dans le milieu. Les hypothèses retenues pour l'élaboration...
Tipo: Text
Ano: 2003
URL: http://archimer.ifremer.fr/doc/00075/18621/16172.pdf

An evaluation of Mg/Ca, Sr/Ca, and Ba/Ca ratios as environmental proxies in aragonite bivalve shells
Provedor de dados: 5
Autores: Poulain, C.; Gillikin, D. P.; Thebault, Julien; Munaron, Jean-marie; Bohn, M; Robert, Rene; Paulet, Yves-marie; Lorrain, Anne.
The influence of salinity and water chemistry on Mg/Ca, Sr/Ca and Ba/Ca ratios in the aragonitic shells of the Manila clam were investigated. Clams were reared at constant temperature (20 °C) under different controlled conditions of salinity, commonly encountered in their natural habitat. Clams were held in three tanks with a constant salinity of 35 for the first 35 days and then two tanks were changed to lower salinities (20 and 28) for the next 29 days. Individual shell Mg/Ca, Sr/Ca and Ba/Ca ratios were studied through time. Despite stable conditions (temperature, salinity, and Mg/Cawater) for clams reared at salinity 35 during the experiment, Mg/Ca shell ratios increased through the time. Moreover the salinity decrease at t35 slowed the increase of...
Tipo: Text
Palavras-chave: Ruditapes philippinarum; Aragonite; Sclerochronology; Bivalved mollusk; Trace element; Proxy.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00245/35649/34158.pdf

New insights into the reproductive cycle of two Great Scallop populations in Brittany (France) using a DEB modelling approach
Provedor de dados: 5
Autores: Gourault, Melaine; Lavaud, Romain; Leynaert, Aude; Pecquerie, Laure; Paulet, Yves-marie; Pouvreau, Stephane.
The present study aimed to improve understanding of the environmental conditions influencing the reproductive cycle of the great scallop Pecten maximus in two locations in Brittany (France). We also evaluated potential consequences of future climate change for reproductive success in each site. We simulated reproductive traits (spawning occurrences and synchronicity among individuals) of P. maximus, using an existing Dynamic Energy Budget (DEB) model. To validate and test the model, we used biological and environmental datasets available for the Bay of Brest (West Brittany, France) between 1998 and 2003. We also applied the scallop DEB model in the Bay of Saint-Brieuc (North Brittany, France) for the same period (1998–2003) to compare the reproductive...
Tipo: Text
Palavras-chave: Pecten maximus; DEB theory; Reproduction cycle; IPCC scenarios; Bay of Brest; Bay of Saint-Brieuc.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00458/57012/58910.pdf

Stable isotope ratios in bentho-demersal biota along a depth gradient in the bay of biscay: A multitrophic study
Provedor de dados: 5
Autores: 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

Cycles saisonniers, reproduction et qualite des ovocytes chez Pecten maximus en rade de Brest
Provedor de dados: 5
Autores: Paulet, Yves-marie; Bekhadra, Farida; Devauchelle, Nicole; Donval, Anne; Dorange, Germaine.
This work is part of the program, "recruitment determinism in scallops" initiated in 1992 by the "Contrat de Baie". The aim of this research was to explain interannual abundance fluctuations observed for Pecten maximus, in the Bay of Brest. To this end an analytical approach to the life cycle of the species was undertaken to determine its critical phases. A phase may be considered as "critical" if the mortality rate at its level varies from one year to the other. Using data from 1989 to 1994, a precise time-table of the "physiological year" of the scallop in the Bay of Brest was determined. Fecundity and gamete production kinetics were estimated from the annual variation in the weight indices of the gonad. In the laboratory, egg quality was estimated...
Tipo: Text
Palavras-chave: Pecten maximus; Recruitment; Reproductive cycle; Digestion.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00044/15495/12861.pdf

Effects of macroalgal accumulations on the variability in zoobenthos of high-energy macrotidal sandy beaches
Provedor de dados: 5
Autores: Quillien, Nolwenn; Nordstrom, Marie C.; Gauthier, Olivier; Bonsdorff, Erik; Paulet, Yves-marie; Grall, Jacques.
Sandy beaches, forming the most widespread coastal habitat in the world, are threatened by the effects of increasing anthropogenic pressure in the context of global change, including the increased occurrence of green tides composed of free-living Ulva spp. Sandy beaches are also highly dynamic ecosystems that support numerous essential ecological functions and contain a distinctive biodiversity, but their precise functioning and natural variability (i.e. the disentangling of biological and physical influences) remain under-studied. Our study aimed at determining the effects of space, time, and environmental variables on the natural variability of macrofaunal community structure and at specifically determining the effects of macroalgal accumulations on the...
Tipo: Text
Palavras-chave: Macrotidal sandy beach; Macrofauna; Green tides; Space-time analysis; Beta-diversity.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00260/37078/73131.pdf

Modeling reproductive traits of an invasive bivalve species under contrasting climate scenarios from 1960 to 2100
Provedor de dados: 5
Autores: Gourault, Melaine; Petton, Sebastien; Thomas, Yoann; Pecquerie, Laure; Marques, Goncalo M.; Cassou, Christophe; Fleury, Elodie; Paulet, Yves-marie; Pouvreau, Stephane.
Identifying the drivers that control the reproductive success of a population is vital to forecasting the consequences of climate change in terms of distribution shift and population dynamics. In the present study, we aimed to improve our understanding of the environmental conditions that allowed the colonization of the Pacific oyster, Crassostrea gigas, in the Bay of Brest since its introduction in the 1960s. We also aimed to evaluate the potential consequences of future climate change on its reproductive success and further expansion. Three reproductive traits were defined to study the success of the reproduction: the spawning occurrence, synchronicity among individuals and individual fecundity. We simulated these traits by applying an individual-based...
Tipo: Text
Palavras-chave: DEB model; IPCC scenarios; Reproductive traits; Crassostrea gigas; Bay of Brest.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00440/55188/56794.pdf