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| Registros recuperados: 40 | |
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| Longphuirt, Sorcha Ni; Lim, Jae-hyun; Leynaert, Aude; Claquin, Pascal; Choy, Eun-jung; Kang, Chang Keun; An, Shu. |
| The importance of intertidal flats as areas of nitrogen filtering has become increasingly apparent in recent times. TO understand fully the cycling of this nutrient. in these areas of high metabolic activity, it is necessary to elucidate the influence of microphytobenthos (MPB) on stocks of ammonium and nitrate in surface areas. In this study, we aimed to quantity nitrogen uptake and relate it to the in Situ concentrations and environmental conditions to which MPB are exposed. In an estuarine system on the Korean Peninsula, we conducted kinetic experiments using N-15 stable isotopes and core sampling over the tidal cycle to determine the temporal evolution of porewater nutrient concentrations and the migration of MPB. The results revealed a range of K-s... |
| Tipo: Text |
Palavras-chave: N 15 stable isotope; Porewater; Microphytobenthos; Kinetic; Nitrogen. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6622.pdf |
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| Guarini, Jean-marc; Blanchard, Gerard; Bacher, Cedric; Gros, Philippe; Riera, Pascal; Richard, Pierre; Gouleau, Dominique; Galois, Robert; Prou, Jean; Sauriau, Pierre-guy. |
| Microphytobenthos plays an important role as primary producer in shallow embayments subject to a tidal regime. The present paper aims to characterize the spatial patterns of sedimentary chlorophyll a (chl a) biomass in 2 seasons in the wide intertidal mudflats of the Marennes-Oleron Bay (France); furthermore, it provides estimates of total microphytobenthic biomass. Accordingly, a systematic sampling scheme was performed in June 1995 and in January 1996. On average, biomass was higher in June (ca 120 mg chl a m-2) than in January (ca 85 mg chl a m-2). Moreover, the geostatistical analysis revealed that spatial similarities were propagated over larger distances in June (6 km) than in January (2.2 km). In order to account for this result , we suggest that... |
| Tipo: Text |
Palavras-chave: Marennes Oleron; Intertidal mudflat; Geostatistics; Spatial distribution; Chrlorophyll a; Microphytobenthos. |
| Ano: 1998 |
URL: https://archimer.ifremer.fr/doc/1998/publication-3820.pdf |
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| Morelle, Jerome; Schapira, Mathilde; Claquin, Pascal. |
| Exopolysaccharides (EPS) play an important role in the carbon flux and may be directly linked to phytoplankton and microphytobenthos production, most notably in estuarine systems. However the temporal and spatial dynamics of estuarine EPS are still not well understood, nor how primary productivity triggers this variability at these different scales. The aim of this study was to investigate the primary productivity of phytoplankton and EPS dynamics in the Seine estuary over a tidal cycle in three different haline zones over two contrasted seasons. The other objectives was to investigate the origin of pools of soluble carbohydrates (S-EPS) and transparent exopolymeric particles (TEP) in phytoplankton, microphytobenthos or other compartments. High frequency... |
| Tipo: Text |
Palavras-chave: Phytoplankton; Microphytobenthos; PAM fluorometer; Electron transport rate. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00400/51132/51898.pdf |
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| Herlory, Olivier; Blanchard, G; Planche, S; Huet, V; Richard, Pierre. |
| Many scientists consider that the top centimetre of the sediment on intertidal mudflats contains the photosynthetic competent biomass (PCB). Part of this biomass migrates upward to the surface of the sediment during diurnal emersion periods to form a temporary biofilm: the photosynthetic active biomass (PAB). The present study tests the hypothesis that the size of the biofilm (PAB) is functionally dependent on PCB. Therefore, we have plotted PAB as a function of PCB for a range of different environmental conditions: 3 seasons and 5 tidal situations, representing a total of 600 cores. This investigation points out that, in spring and autumn, there was a simple linear relationship between PAB and PCB, thus indicating that the maximum size of the biofilm... |
| Tipo: Text |
Palavras-chave: Functional relationship; Biofilm; Biomass; Intertidal mudflat; Microphytobenthos. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-3622.pdf |
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| 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 |
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| Morelle, Jérôme. |
| The estuaries play an important ecological role and are the site of many human activities because of their strategic position at the interface between continental and marine waters. Seine estuary is characteristic of large anthropized estuaries. Long-term management requires better knowledge of the spatial and temporal dynamics of the estuarine food webs. Phytoplankton and microphytobenthos are the main contributor of primary production (PP) in these ecosystems and are at the basis of trophic food webs. These compartments are often reduced to the chlorophyll concentration and their productivity has never been measured along the Seine estuary. The objective of this study was to estimate the PP of these compartments along the salinity gradient. In order to... |
| Tipo: Text |
Palavras-chave: PAM; ETR; 13C; TEP; EPS; Exopolymeric substances; Phytoplankton; Microphytobenthos; Transparent Exopolymeric Particles. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00498/60965/64373.pdf |
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| Bacher, Cedric; Blanchard, Gerard; Bougrier, Serge; Cariou-le Gall, Valerie; Delmas, D.; Deslous Paoli, Jean-marc; Dinet, A.; Garet, Marie-josee; Geairon, Philippe; Jonquieres, Gerard; Laisne, A.; Maffei, E.; Montagna, P. A.; De Montaudouin, Xavier; Morin, S.; Richard, P.; Riera, Pascal; Sauriau, Pierre-guy; Vrignaud, N.. |
| Les cartographies annuelles des biomasses microphytobenthiques ont été réalisées pour le bassin de Marennes-Oléron. Parallèlement les cartographies des caractéristiques sédimentaires ont été établies simultanément aux cartes d'abondance et biomasse macrofauniques en portant un effort particulier sur les densités des compétiteurs des huîtres notamment les Crépidules. Simultanément les études des mécanismes contrôlant le réseau trophique sur la vasière de Brouage ont été poursuivies notamment les relations entre les flux de sels nutritifs et le microphytobenthos. L'importance de ce dernier compartiment dans la nutrition de l'huître a été clairement mis en évidence par l'utilisation des traçeurs isotopiques naturels. Enfin, les caractéristiques de filtration... |
| Tipo: Text |
Palavras-chave: Bassin de Marennes Oléron; Microphytobenthos; Physiologie; Crassostrea gigas; Crépidules; Modèle réseau trophique; Cartographie; Charente-Maritime. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00102/21294/18911.pdf |
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| Lebreton, Benoit; Richard, Pierre; Radenac, Gilles; Bordes, Monique; Breret, Martine; Arnaud, Christophe; Mornet, Francoise; Blanchard, Gerard F.. |
| The role of epiphytes in an intertidal Zostera noltii seagrass bed in Marennes-Oleron Bay was assessed in comparison with the other main benthic primary producers (Z. noltii, microphytobenthos) at two bathymetric levels and on a seasonal basis. Assemblage and biomass of epiphytes were studied using scanning electron microscopy (SEM). Z noltii and its detrital matter followed a typical seasonal pattern: microphytobenthos was present in large quantities throughout the year representing 21% of the total biomass while detrital matter, above-ground parts and below-ground parts accounted for 65, 9 and 5%, respectively. Only two species of epiphytic diatoms, Cocconeis scutellum and Cocconeis placentula, were observed on seagrass leaves. Epiphyte biomass was very... |
| Tipo: Text |
Palavras-chave: SEM; Cocconeis spp.; Epiphyte diatom; Microphytobenthos; Zostera noltii; Intertidal seagrass bed; Primary producer. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6589.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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| Sagan, G; Thouzeau, G. |
| Microphytobenthic biomass was estimated in the Bay of Brest (1994) and the western English Channel (Trezen Vraz, 1993) using spectrophotometry. Best results (42 % difference) were obtained with an instantaneous extraction procedure at room temperature, compared with the cold extraction procedure. Chlorophyll biomass in sediment was higher in the western English Channel (65-215 mg Chl a m(-2)) than in the Bay of Brest (10-113 mg Chl a m(-2)), in contrast to total pigment biomass (Chl a + pheo a : 88-254 mg m(-2) at Trezen Vraz vs. 131-934 mg m(-2) in the Bay of Brest). This study emphasized decreasing pigment biomass from the estuary to the open sea. Low benthic pigment biomass in the Bay, compared to eutrophic ecosystems, agrees with previous studies on... |
| Tipo: Text |
Palavras-chave: Microphytobenthos; Biomasse; Écosystèmes côtiers; Forçage physique; Microphytobenthos; Biomass; Coastal ecosystems; Physical forcing. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00325/43651/43242.pdf |
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| Pigeot, J; Miramand, P; Guyot, T; Sauriau, Pierre-guy; Fichet, D; Le Moine, Olivier; Huet, V. |
| The Marennes-Oleron Bay is subject to chronic pollution by cadmium (Cd) from the Gironde watershed. An ecosystem approach was used to study the fate of cadmium in the different biological compartments. The median Cd concentration was 0.4 mu g g(-1) dry weight for the 63 benthic species measured. When combined with the respective biomasses for the different species studied, we estimated that 7 kg of Cd is partitioned into the soft tissues of the benthic species in the bay. The majority of this cadmium was distributed between primary producers, mainly microphytobenthos (40 %), and suspension-feeders, mainly oysters (40 %). All other benthic species measured were associated with negligible masses of Cd. Two trophic levels contained 98 % of the Cd: 3 kg was... |
| Tipo: Text |
Palavras-chave: Marennes Oleron Bay; Trophic food web; Bioaccumulation; Cadmium; Macrofauna; Microphytobenthos; Macrophytes. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-3615.pdf |
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| 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 |
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| Zurburg, Wouter; Smaal, Aad; Heral, Maurice; Dankers, Norbert. |
| Within the framework of an investigation into the carrying capacity of the Bay of Marennes-Oléron (France) for bivalve culture, the in situ uptake of suspended particulate material by oysters (Crassostrea gigas) and mussels (Mytilus edulis) was determined in experiments with benthic ecosystem tunnels. Very high fluctuations in seston quantity and quality were observed within and between tidal cycles. The percentage of organic carbon was inversely related to seston quantity at low concentrations. Organic carbon was diluted by resuspension of material rich in inorganic matter. At high seston concentrations a constant level of about 2% organic carbon was found. The CIN ratio was relatively constant throughout the seasons and fairly low (6.5 to 8.4). Owing to... |
| Tipo: Text |
Palavras-chave: Microphytobenthos; Chlorophyll; Feeding; Mussel; Oyster; Seston quality; Seston load. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/1994/publication-6843.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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| Niquil, Nathalie; Kerleguer, G; Leguerrier, D; Richard, Pierre; Legrand, Helene; Dupuy, Christine; Pascal, P; Bacher, Cedric. |
| The presence of herbicides in the run-off water coming over Brouage mudflat (Marennes-Oleron Bay, France) is suspected to cause a loss of primary production by benthic diatom biofilm. Microphytobenthos being the main primary producer of this ecosystem, it was questioned about what could be the effect of such a modification of primary production on the entire food web that depends on it. The probable impacts were investigated through a sensitivity analysis conducted on the steady-state model of the Brouage mudflat, coupling two seasons and trophic-hydrodynamic flows. The loss of benthic primary production had an effect on compartments at a low trophic level, but was buffered at higher levels because of the compensation of herbivory by other pathways and... |
| Tipo: Text |
Palavras-chave: Intertidal mudflat food web; Pollution; Microphytobenthos; Inverse analysis; Sensitivity analysis. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-3613.pdf |
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| Registros recuperados: 40 | |
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