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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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Parodi, Er; Barria De Cao, S. |
The intertidal zone of the inner part of the Bahia Blanca estuary, Argentina is characterised by the presence of muddy tidal flats and salt marshes, habitats for burrowing crabs and halophytic plants. The surface layer of the sediments is composed of silt and clay. The sediments are substrate for the proliferation of benthic microalgal communities. The aim of this study was to analyse qualitatively the species composition of these communities and their role in the stabilisation of the sediments. Samples came from two stations: Puerto Cuatreros and Villarino Viejo. Puerto Cuatreros is an old pier without harbour activities closer than Villarino Viejo to the harbour zone affected by dredging. Both stations showed similar physical and chemical parameters. In... |
Tipo: Text |
Palavras-chave: Microphytobenthos; Stabilisation des sédiments; Benthic microalgal communities; Microbial mats; Sediments stabilisation. |
Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/00322/43311/42963.pdf |
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Herlory, Olivier; Guarini, Jean-marc; Richard, Pierre; Blanchard, Gerard. |
The spatio-temporal dynamics of the microphytobenthic biofilm was analysed at microscale over a complete day-time emersion period in an intertidal mudflat. The structures of the biofilm were monitored by analysing the variability of the epipelic diatom cover in the horizontal dimension and the kinetics of biomass dispersion in the vertical dimension. Colonisation of the sediment surface by diatoms was rapid (within 15 min); 75% of the biomass contained in the top 1 mm was concentrated in the upper 200 mum, but the cover never reached 100%. This biomass had a higher chlorophyll a/pheopigment ratio than deeper in the sediment, suggesting a better physiological state and a higher photosynthetic potential. The dynamics of the biomass in the upper 200 mum... |
Tipo: Text |
Palavras-chave: Microphytobenthos; Biofilm; Intertidal mudflat; Spatio temporal dynamics; Microscale. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/00000/10905/7580.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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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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Kostecki, Caroline; Roussel, J. M.; Desroy, Nicolas; Roussel, G.; Lanshere, J.; Le Bris, H.; Le Pape, Olivier. |
Coastal and estuarine nurseries are essential habitats for juvenile flatfish. These small but productive areas provide food supply and sustain adult fish populations. The Mont-Saint-Michel Bay (MSMB) supports an important flatfish nursery ground but differs from many other nursery habitats due to limited freshwater inputs. The objectives of the present study in the MSMB were to (1) use gut content analysis to identify prey of the 2 most abundant flatfish species (common sole Solea solea and plaice Pleuronectes platessa) for different juvenile age-classes (0-group and 1-group for sole, 0-group for plaice), (2) use C and N stable isotope analysis to model the production sources sustaining juvenile flatfish production, and (3) compare these results with... |
Tipo: Text |
Palavras-chave: Microphytobenthos; Organic matter origin; Benthic food web; Coastal nursery ground; Juvenile flatfish. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00073/18438/15976.pdf |
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Riera, P; Richard, P; Gremare, A; Blanchard, G. |
Nematodes living on an intertidal mudflat of the Marennes-Oleron Bay (France) were assayed for delta(13)C and delta(15)N ratios together with their potential food resources between July 1992 and May 1993. Results suggest that nematodes do not exploit all the components of the sedimented organic matter (SOM) pool at the same rate. Furthermore, based on coefficients of average trophic enrichment found in the literature for both C and N, the enrichment of nematodes in C-13 and their depletion in N-15 relative to SOM suggest that microphytobenthos constitutes their main food source in this particular environment. |
Tipo: Text |
Palavras-chave: Nematodes; Microphytobenthos; Food sources; Stable isotope ratios. |
Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00282/39288/43132.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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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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Guarini, Jean-marc; Blanchard, Fabian; Bacher, Cedric; Gros, Philippe; Riera, P; Richard, P; Gouleau, D; Galois, R; Prou, Jean; Sauriau, Pg. |
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 chi a m(-2)) than in January (ca 85 mg chi 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 or this result, we suggest that... |
Tipo: Text |
Palavras-chave: Microphytobenthos; Chlorophyll a; Spatial distribution; Geostatistics; Intertidal mudflat. |
Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00447/55852/58117.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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Legrand, Helene; Herlory, Olivier; Guarini, Jean-marc; Blanchard, Gerard; Richard, Pierre. |
Atrazine and diuron are two herbicides present in sediments of the intertidal mudflats in the Pertuis Charentais (Atlantic coast, France). They may negatively affect photosynthesis processes in microphytobenthos, the most productive primary producer in these environments. The impact of these herbicides on benthic diatoms was investigated using PAM fluorimetry on natural microalgal communities, once extracted from sediment, by following the variations of the effective quantum yield of PSII (Phi(PSII)) during exposure to atrazine and diuron concentrations in a range 0.1 mu g L-1 (.) 10 mg L-1. No significant effect was noticed for 0.1 mu g L-1 concentrations, but progressive reduction in photosynthetic efficiency, always occurring within 15 min, was... |
Tipo: Text |
Palavras-chave: Diuron; Atrazine; PAM; Chlorophyll fluorescence; Microphytobenthos. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-3614.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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Hochard, Sébastien; Royer, Florence; Hubert, Morgane; Lemonnier, Hugues. |
The evolution of benthic pelagic coupling was followed in two semi-intensive shrimp ponds in New Caledonia, with a special emphasis on the role of microphytobenthos (MPB). Three distinct periods could be identified. During the first period, MPB activity led to relative decoupling between the water column and the sediment, both compartments being autotrophic with low nutrients exchanges. During the second period, the sediment operated at the edge of a functional switch between autotrophy and heterotrophy. The amplitude of nutrient fluxes depended of the pool considered (DIN, DIP) and showed light dark variation. In the last period, sediment switched to heterotrophy with the establishment of benthic-pelagic coupling concomitantly to a massive sediment... |
Tipo: Text |
Palavras-chave: Tropical aquaculture; Shrimp; Eutrophication; Benthic-pelagic coupling; Microphytobenthos; Bioturbation. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00485/59681/62754.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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Registros recuperados: 40 | |
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