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| Registros recuperados: 22 | |
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| Donis, Daphne; Holtappels, Moritz; Noss, Christian; Cathalot, Cecile; Hancke, Kasper; Polsenaere, Pierre; Wenzhoefer, Frank; Lorke, Andreas; Meysman, Filip J. R.; Glud, Ronnie N.; Mcginnis, Daniel F.. |
| The quantification of benthic fluxes with the aquatic eddy correlation (EC) technique is based on simultaneous measurement of the current velocity and a targeted bottom water parameter (e.g., O2, temperature). High-frequency measurements (64 Hz) are performed at a single point above the seafloor using an acoustic Doppler velocimeter (ADV) and a fast-responding sensor. The advantages of aquatic EC technique are that 1) it is noninvasive, 2) it integrates fluxes over a large area, and 3) it accounts for in situ hydrodynamics. The aquatic EC has gained acceptance as a powerful technique; however, an accurate assessment of the errors introduced by the spatial alignment of velocity and water constituent measurements and by their different response times is... |
| Tipo: Text |
Palavras-chave: Turbulence; Boundary layer; Fluxes; Instrumentation/sensors; Optimization; Experimental design. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00275/38577/37102.pdf |
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| Soletchnik, Patrick; Le Moine, Olivier; Polsenaere, Pierre. |
| Entre 1977 et 2015, la température des eaux de surface du Bassin de Marennes-Oléron (référence station Boyard) a augmenté en moyenne de 1,5 °C. Le réchauffement principal a eu lieu entre les années 1982-83 et 1997-99. L’étude compare deux périodes « avant » (1977-1991) et « après » (2000-2015) le réchauffement. Elle met en évidence une « salinisation » estivale des eaux de surface dans le nord du bassin de Marennes-Oléron, avec +1,2 ; +0,7 et +0,7 de salinité pour les mois de juin, juillet et août. La contribution des fleuves aux apports dans le bassin de Marennes, simulée en juin 2014 et 2015, montre à cette période, sur le site de Boyard, une influence des fleuves externes, supérieure à celle des fleuves internes. L’étude des débits de la Loire,... |
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| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00359/46986/46903.pdf |
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| Pepin, Jean-francois; Soletchnik, Patrick; Le Moine, Olivier; Polsenaere, Pierre; Genauzeau, Sylvie; Robert, Stephane; Grizon, James; Seugnet, Jean-luc; Schmitt, Anne; Chabirand, Jean-michel; Tourbiez, Delphine; Travers, Marie-agnes; Guesdon, Stephane. |
| We report in this work data of two independent studies carried out in the Pertuis Charentais for which a link might exist? A 30-years local time series study of hydro-climatic variations in water temperature and salinity, which show a significant warming of the water masses in the Marennes Oleron bay (+ 1.5 °C) associated with a significant drop ( > -15%) of freshwater intakes by nearby rivers. In this changing local climate context several major epizootics have appeared, severely affecting farmers and the production of Pacific oysters and mussels, from the first French shellfish-producing department (catching and growing, Agreste, 2012). Following massive mortality event of blue mussels in 2014, a specific study (MORBLEU) is conducted, trying to... |
| Tipo: Text |
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| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00415/52697/53567.pdf |
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| Berg, Peter; Delgard, Marie Lise; Polsenaere, Pierre; Mcglathery, Karen J.; Doney, Scott C.; Berger, Amelie C.. |
| Seagrass meadows play an important role in “blue carbon” sequestration and storage, but their dynamic metabolism is not fully understood. In a dense Zostera marina meadow, we measured benthic O2 fluxes by aquatic eddy covariance, water column concentrations of O2, and partial pressures of CO2 (pCO2) over 21 full days during peak growing season in April and June. Seagrass metabolism, derived from the O2 flux, varied markedly between the 2 months as biomass accumulated and water temperature increased from 16°C to 28°C, triggering a twofold increase in respiration and a trophic shift of the seagrass meadow from being a carbon sink to a carbon source. Seagrass metabolism was the major driver of diurnal fluctuations in water column O2 concentration and pCO2,... |
| Tipo: Text |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00504/61565/65490.pdf |
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| Polsenaere, Pierre; Le Marchand, Marie; Le Moine, Olivier; Soletchnik, Patrick; Chabirand, Jean-michel; Geairon, Philippe; Thomas, Gerard; Bechemin, Christian; Souchu, Philippe; Joyeux, Emmanuel; Le Roy, Yoann; Corre, Frédéric. |
| Tipo: Text |
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| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00405/51629/52184.pdf |
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| Soletchnik, Patrick; Polsenaere, Pierre; Le Moine, Olivier. |
| Historiquement, les pêches de larves de l’huître creuse (C. gigas) ont lieu en six stations du BMO depuis les années 70, de début juin à la première semaine de septembre. La comparaison des captures saisonnières et hebdomadaires entre les périodes P1 (1977-1991) et P2 (2000-2015) montre un ajustement de la distribution des captures de larves à un modèle polynomiale d’ordre 4 pour P1 (R2 = 0,77), puis d’ordre 2 pour P2 (R2 = 0,86). Les modèles de distribution des captures montrent que la saison de reproduction a doublé entre les deux périodes. Elle s’étend aujourd’hui de juin à septembre. Devant l’extension de la saison de reproduction, la saison de pêche expérimentale est aujourd’hui trop réduite. Toutefois, le pic d’abondance des captures n’a pas changé... |
| Tipo: Text |
Palavras-chave: Huître; C. gigas; Changement global; Réchauffement climatique; Reproduction; Larve; Mortalité; Phénologie; Ostréiculture; Bassin de Marennes Oléron; Phytoplancton; Chlorophylle a; Température. |
| Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00441/55239/56723.pdf |
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| Bechemin, Christian; Soletchnik, Patrick; Polsenaere, Pierre; Le Moine, Olivier; Pernet, Fabrice; Protat, Martin; Fuhrmann, Marine; Quere, Claudie; Goulitquer, Sophie; Corporeau, Charlotte; Lapegue, Sylvie; Travers, Marie-agnes; Morga, Benjamin; Garrigues, Manon; Garcia, Celine; Haffner, Philippe; Dubreuil, Christine; Faury, Nicole; Baillon, Laury; Baud, Jean-pierre; Renault, Tristan. |
| Mass mortality outbreaks (90-100%) in both juvenile and adult blue mussels were reported in 2014 along the Pertuis Charentais area of the French Atlantic coast. A series of studies were carried out to learn more about the phenomenon through detecting pathogens, describing environmental conditions and establishing the physiological status of the animals. Bacteria identif ied as belonging to the V. splendidus species were detected in dying mussels and seem able to cause mortality in blue mussels in the laboratory. Unusual environmental conditions (large amounts of fresh water, re-suspension of sediments during a series of storms, and a high renewal rate of specific water masses in Brittany’s Pertuis area) may be partially responsible for sparking the phenomen |
| Tipo: Text |
Palavras-chave: Mortalités; Moules; Pertuis Charentais; Vibrio splendidus; Environnement; Mortality; Mussels; Pertuis Charentais; Vibrio splendidus; Environment. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00312/42343/41682.pdf |
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| Soletchnik, Patrick; Le Moine, Olivier; Polsenaere, Pierre. |
| Dans le contexte du changement global dont la cause anthropique est maintenant reconnue, cette étude dresse un bilan de l’évolution hydro-climatique des Pertuis Charentais (Bassin de Marennes-Oléron) depuis les quarante dernières années. Elle présente une comparaison de la situation hydro-climatique avant et après la « rupture thermique » des années 80-90, reconnue à l’échelle de l’hémisphère Nord et mise également en évidence dans les Pertuis entre 1983-1997. Les deux périodes comparées sont (1977-1991) d’une part et (2000-2015) d’autre part. Entre les deux, l’élévation des températures de l’eau de mer de 1,5°C en moyenne et 3°C en médiane, s’est accompagnée d’une élévation de la salinité (0,6 à 0,9) en lien avec un déficit d’apport des fleuves internes... |
| Tipo: Text |
Palavras-chave: Hydrologie; Hydro-climat; Hydrodynamique; Bassin de Marennes-Oléron; Evolution; Réchauffement climatique; Apports; Fleuves; Température; Salinité; Nutriments; Chlorophylle a. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00387/49815/50391.pdf |
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| Van Dam, Bryce; Polsenaere, Pierre; Barreras-apodaca, Aylin; Lopes, Christian; Sanchez-mejia, Zulia; Tokoro, Tatsuki; Kuwae, Tomohiro; Guttierrez Loza, Lucia; Rutgersson, Anna; Fourqueren, James; Thomas, Helmut. |
| Coastal vegetated habitats like seagrass meadows can mitigate anthropogenic carbon emissions by sequestering CO2 as “blue carbon” (BC). Already, some coastal ecosystems are actively managed to enhance BC storage, with associated BC stocks included in national greenhouse gas inventories. However, the extent to which BC burial fluxes are enhanced or counteracted by other carbon fluxes, especially air‐water CO2 flux (FCO2) remains poorly understood. In this study, we synthesized all available direct FCO2 measurements over seagrass meadows made using atmospheric Eddy Covariance, across a globally‐representative range of ecotypes. Of the four sites with seasonal data coverage, two were net CO2 sources, with average FCO2 equivalent to 44 ‐ 115% of the global... |
| Tipo: Text |
Palavras-chave: Seagrass; Blue Carbon; CO2 Flux; Eddy Covariance; Carbon Cycle; Air‐sea interaction. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00682/79435/82041.pdf |
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| Savelli, Raphael; Bertin, X.; Orvain, Francis; Gernez, P.; Dale, A.; Coulombier, T.; Pineau, P.; Lachaussée, N.; Polsenaere, Pierre; Dupuy, C.; Le fouest, V.. |
| Microphytobenthos (MPB) resuspension is a key mechanism in the transfer of organic matter from productive intertidal mudflats to terrestrial and marine systems. In this study, we infer on the contribution of physical and biological factors involved in the MPB resuspension. We use a physical‐biological coupled model forced by realistic meteorological and hydrodynamical forcings to simulate chronic (without any concomitant sediment resuspension) and massive (driven by bed failure) resuspension over a year. The model simulates mud surface temperature, MPB growth, and grazing by the gastropod Peringia ulvae. The model suggests that MPB resuspension is the highest in spring tides and at the flood beginning due to high current velocity and low water heights that... |
| Tipo: Text |
Palavras-chave: Microphytobenthos; Mudflat; Resuspension; Physical-biological coupling; Numerical modeling. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00599/71114/69416.pdf |
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| Méléder, Vona; Savelli, Raphael; Barnett, Alexandre; Polsenaere, Pierre; Gernez, Pierre; Cugier, Philippe; Lerouxel, Astrid; Le Bris, Anthony; Dupuy, Christine; Le Fouest, Vincent; Lavaud, Johann. |
| The gross primary production (GPP) of intertidal mudflat microphytobenthos supports important ecosystem services such as shoreline stabilization and food production, and it contributes to blue carbon. However, monitoring microphytobenthos GPP over a long-term and large spatial scale is rendered difficult by its high temporal and spatial variability. To overcome this issue, we developed an algorithm to map microphytobenthos GPP in which the following are coupled: (i) NDVI maps derived from high spatial resolution satellite images (SPOT6 or Pléiades), estimating the horizontal distribution of the microphytobenthos biomass; (ii) emersion time, photosynthetically active radiation (PAR), and mud surface temperature simulated from the physical model MARS-3D;... |
| Tipo: Text |
Palavras-chave: Microphytobenthos; Intertidal mudflat; Gross primary production; Remote sensing; NDVI; Modeling. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00643/75531/76429.pdf |
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| Savelli, Raphael; Méléder, Vona; Cugier, Philippe; Polsenaere, Pierre; Dupuy, Christine; Lavaud, Johann; Barnett, Alexandre; Le Fouest, Vincent. |
| Microphytobenthos (MPB) at the sediment surface of intertidal mudflats are known to show a high spatial and temporal variability in response to the biotic and abiotic conditions prevailing at the mud surface. It makes long-term and large-scale monitoring of MPB Gross Primary Production (GPP) difficult to set up. In this study, we developed the first 3D physical-biological coupled model (MARS-3D) that explicitly simulates GPP of intertidal MPB at the mudflat scale, and we compared the outputs with in situ and space remote sensing MPB GPP data. We discuss the sources of discrepancies between the modeling and the remote sensing approach in the light of future developments to be done. For instance, the remote sensing algorithm provides a very synoptic view of... |
| Tipo: Text |
Palavras-chave: Microphytobenthos; Intertidal mudflat; Gross primary production; Remote sensing; Physical-biological modeling. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00654/76612/77764.pdf |
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| Savelli, Raphael; Dupuy, Christine; Barille, Laurent; Lerouxel, Astrid; Guizien, Katell; Philippe, Anne; Bocher, Pierrick; Polsenaere, Pierre; Le Fouest, Vincent. |
| Microphytobenthos (MPB) from intertidal mudflats are key primary producers at the land–ocean interface. MPB can be more productive than phytoplankton and sustain both benthic and pelagic higher trophic levels. The objective of this study is to assess the contribution of light, mud temperature, and gastropod Peringia ulvae grazing pressure in shaping the seasonal MPB dynamics on the Brouage mudflat (NW France). We use a physical–biological coupled model applied to the sediment first centimetre for the year 2008. The simulated data compare to observations, including time-coincident remotely sensed and in situ data. The model suggests an MPB annual cycle characterised by a main spring bloom, a biomass depression in summer, and a moderate fall bloom. In early... |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00471/58226/60732.pdf |
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| Polsenaere, Pierre; Soletchnik, Patrick; Le Moine, Olivier; Gohin, Francis; Robert, Stephane; Pepin, Jean-francois; Stanisiere, Jean-yves; Dumas, Franck; Bechemin, Christian; Goulletquer, Philippe. |
| In the context of global change, increasing mariculture production has raised particular concerns regarding its environmental impact and sustainability. Molluscs and particularly blue mussel account for a significant part of this total production. Although blue mussels are considered as pretty resilient to environmental disturbances, we report in this study an unprecedented mussel mortality event that occurred during the winter 2014 in the Breton Sound. 9000 metric tonnes of mussels were lost and mortality rates up to 100% were recorded at some farming areas. Through a coupling approach, the present work aimed to better understand the potential environmental drivers associated to those mortalities. Firstly we analysed long-term in situ and satellite data... |
| Tipo: Text |
Palavras-chave: Mytilus edulis mortalities; Climate change; Breton sound; Long-term monitoring; Hydrodynamic modelling; Vibriosis. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00376/48708/49083.pdf |
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| Thomas, Gerard; Piquet, Jean-come; Ryckaert, Mireille; Masson, Daniel; Pepin, Jean-francois; Polsenaere, Pierre; Fillon, Alain. |
| Marine environment contamination can affect fishing and shellfish farming products (and shellfish in the first place), thus making them improper for human consumption, threatening public health and producer’s business. Analysis and health risk management are mandatory for consumer’s security and shellfish production survival. About microbial risk, monitoring shellfish production areas and several studies carried by LERPC laboratory give a good view of the microbial contamination impacting the Pertuis Charentais shellfish production area. On the other hand, State-Region Plan Contract (CPER) studies results from 2007 to 2013 are presented and discussed; additionally, the law-prescribed sanitary studies for professional on foot-fishing classification are... |
| Tipo: Text |
Palavras-chave: Microbiologie; E. coli; Norovirus; Étude sanitaire; Conchyliculture; Pêche à pied professionnelle; Pertuis Charentais; Microbiology; E.coli; Norovirus; Sanitary(health) studies; Shellfish farming; On foot]fishing; Pertuis Charentais.. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00302/41299/40472.pdf |
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| Bechemin, Christian; Soletchnik, Patrick; Polsenaere, Pierre; Le Moine, Olivier; Pernet, Fabrice; Protat, Martin; Fuhrmann, Marine; Quere, Claudie; Goulitquer, Sophie; Corporeau, Charlotte; Renault, Tristan; Lapegue, Sylvie; Travers, Marie-agnes; Morga, Benjamin; Garriques, Manon; Garcia, Celine; Haffner, Philippe; Dubreuil, Christine; Faury, Nicole; Baillon, Laury; Baud, Jean-pierre. |
| Suite aux surmortalités observées au sein des élevages de moules touchant à la fois les animaux adultes et les juvéniles au mois de mars, dans les Pertuis Charentais, la Direction Générale de l’Alimentation (DGAl) a adressé une saisine à Ifremer le 04 avril 2014. Celle-ci fait état d’une demande d’appui scientifique et technique d’Ifremer pour tenter d’apporter des éléments de réponse par rapport à cette mortalité subite et importante. L’Ifremer a proposé un projet d’action permettant l’expertise du phénomène de surmortalité de la moule bleue, selon 3 axes : l’impact environnemental, la pathologie et les caractéristiques physiologiques des moules. Il s’agit de mettre en évidence la présence ou non d’agents infectieux connus ou émergents, d’apporter des... |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00229/34022/32387.pdf |
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| Polsenaere, Pierre; Deborde, Jonathan; Detandt, Guillaume; Vidal, Luciana O.; Perez, Marcela A. P.; Marieu, Vincent; Abril, Gwenael. |
| In November 2011, the partial pressures of carbon dioxide (pCO(2)) in water and air in a floodplain lake of the Amazon River in Brazil were 800 +/- 75 and 387 +/- 8 ppmv, respectively. Turbulent CO2 fluxes from the lake measured with eddy covariance ranged from 0.05 to 2.2 mmol m(-2) s(-1). The corresponding gas transfer velocities k(600) ranged from 1.3 to 31.6 cm h(-1), averaging 12.2 +/- 6.7 cm h(-1). At moderate to high wind speed, k(600) increased with wind speed, with values above parameterizations for other lake ecosystems. During the prevailing tropical low wind speed (below 2.7 m s(-1)) and high insolation conditions, unexpected high k(600) values (up to 20 cm h(-1)) were obtained and correlated with latent heat and sensible heat fluxes. In... |
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| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00603/71532/69950.pdf |
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| Coignot, Elise; Polsenaere, Pierre; Soletchnik, Patrick; Le Moine, Olivier; Souchu, Philippe; Joyeux, Emmanuel; Le Roy, Yoann; Guéret, Jean-pierre; Froud, Louise; Gallais, Régis; Chourré, Elise; Chaigneau, Loïc. |
| Les zones côtières en raison de leur statut d’interface entre les continents, les océans et l’atmosphère constituent un environnement particulièrement actif et impliqué dans les cycles biogéochimiques. Elles sont le réceptacle de molécules particulaires et dissoutes véhiculées par les rivières et impliquées à la fois dans la chaine trophique et dans les phénomènes d’eutrophisation ou de toxicité. Cette étude a pour objectif d’étudier la dynamique des nutriments et du carbone au niveau d’un continuum terrestre-aquatique formé par le Marais poitevin (MP), la Baie de l’Aiguillon (BA) et le Pertuis Breton (PB). L’étude a été réalisée sur deux années (2017 et 2018) contrastées en terme de pluviométrie. Au total, huit sites (deux estuaires, trois chenaux et... |
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| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00618/73003/72077.pdf |
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| Registros recuperados: 22 | |
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