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| Registros recuperados: 105 | |
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| Guerault, Daniel; Desaunay, Yves; Bellois, Pierre; Grellier, Patrick; Robin, Jean-paul; Robineau, Brigitte. |
| A survey of the glass-eel fishery in the Loire estuary in 1987 (265 boats, 117 tons gasseel, 13733 fishing trips) showed that 16 fishery species constitute the by-catch (49,3 million individuals, mainly juveniles, among which 98 % consist in flounder, sprat and brown shrimp). The analysis of catches in space and time leads to proposaIs for Iimiting the impact during the last fishing weeks. Taking into account the naturai mortality rates of the concerned juveniles, an attempt is made to estimate the actuai impact of the glasseel fishery, after a delay. Only 10 % of the caught brown shrimps wouid have been recruited in the summer shrimp fishery. Up to 85,5 to 97,6 % of juvenile fishes would have disappeared during the following year by natural mortality. |
| Tipo: Text |
Palavras-chave: Anguille; Pêcherie; Prises accessoires; Estuaire; Loire; Eel; Fishery; By catch; Estuary; Loire. |
| Ano: 1989 |
URL: http://archimer.ifremer.fr/doc/00120/23102/20951.pdf |
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| Riera, Pascal. |
| This study examined the delta(15)N of suspended and sedimented particulate organic matter, primary sources of organic matter and benthic invertebrates along an estuarine gradient in Marennes-Oleron Bay, France. Particular emphasis was given to the use of delta(15)N as a tracer of the origin of organic matter and as a means of determining the benthic food web structure in estuarine environments. delta(15)N values indicated that there was direct utilisation of benthic diatoms as a food source by oyster Crassostrea gigas near intertidal mudflats but suggested trophic mediation between terrestrial detritus and oysters in the upper estuarine reaches. delta(15)N data showed that the trophic position of oysters may vary in the estuarine bay. The delta(15)N values... |
| Tipo: Text |
Palavras-chave: Nitrogen isotope ratio; Particulate organic matter; Crassostrea gigas; Benthic food web; Estuary; Marennes-Oleron Bay. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00448/55926/57786.pdf |
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| Le Joncour, Anna; Blanchard, Fabian; Tagliarolo, Morgana. |
| Estuarine and coastal areas are often considered as hotspots due to their high diversity and ecological importance. However, communities living on those areas are often submitted to fishery and climate change pressures causing modifications on fish assemblages. French Guiana’s coastal shelf is characterised by warm waters with high turbidity and low salinity caused by the large river discharges from the Amazon and nearby estuaries. The high productivity of these areas supports fisheries and aquaculture activities. However, the structure and dynamics of coastal fish populations in French Guiana have seldom been studied. The aim of this study was to understand the effect of environmental conditions, as well as the influence of the coast and nearby estuaries... |
| Tipo: Text |
Palavras-chave: French Guiana; Coastal community; Estuary; Diversity; Tropical waters; Fisheries management. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00607/71929/73534.pdf |
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| Pougnet, F.; Blanc, G; Mulamba-guilhemat, E.; Coynel, A.; Gil-diaz, T.; Bossy, C.; Strady, E.; Schäfer, J.. |
| Despite major management efforts initiated in 1987 and 2007 and decreasing emissions in the Gironde watershed, cadmium (Cd) levels in oysters from the downstream Gironde estuary are still higher to the consumption limit (5 mg/kg, dw, EC). Dissolved Cd concentrations were measured in surface water collected in the Gironde estuary during nine cruises (2014 – 2015). The obtained theoretical (Cdd0) concentrations and the daily net Cdd fluxes, using the Boyle’s method, confirm a decadal stepping decrease of the Cd pollution corresponding to that observed in the oysters from the long term national monitoring for priority contaminants at the estuary mouth. As this observation invalidates the previous estimating methods for estimating annual net Cdd fluxes, we... |
| Tipo: Text |
Palavras-chave: Estuaire; Cadmium dissous; Modélisation; Flux nets; Estuary; Dissolved cadmium; Computation; Net fluxes. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00485/59713/62808.pdf |
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| Morin, Jocelyne; Riou, Philippe; Bessineton, Christophe; Vedieu, Christophe; Lemoine, Michel; Simon, Serge; Le Pape, Olivier. |
| This study, carried out from 1995 to 1997, within the framework of "Le Havre" harbour extension project, concerned halieutic populations and the characterization of a coastal nursery in the oriental part of the Seine bay and the Seine estuary . The main objective was to describe the specific and demographic composition of marine populations and their spatio-temporal distribution, and so assess the biological and halieutic role of this area. This study also included a research about the dietary needs of fish juveniles living in the estuary. Autumn and winter surveys results show that the estuary and area under direct influence are the richest from a biological and halieutic point of view. The mouth estuary isthe richest area in terms of diversity of... |
| Tipo: Text |
Palavras-chave: Bay of Seine; Estuary; Food; Trophic; Juvenile; Nursery; Baie de Seine; Estuaire; Alimentation; Trophique; Juvénile; Nourricerie. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/1999/rapport-1507.pdf |
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| Brandão, Manoela; Stumpf, Liane; Macedo-soares, Luis; Freire, Andrea. |
| This study investigated the abundance and composition of brachyuran crab larvae in the four subsystems of Ibiraquera Lagoon throughout the year. A colder and drier period was detected, contrasting with warm months during which salinity varied depending on rainfall and whether the sand bar was open or closed. The mean density of brachyuran zoeae was 540 ± 96 (SE) larvae · 100 m-3. Mean density was significantly (p<0.05) higher in three subsystems during April. Saco Lagoon (the outer subsystem) exhibited significantly higher (p<0.05) mean density in July, August, October, November and December 2004. Larvae from the families Portunidae, Menippidae, Panopeidae, Ocypodidae and Varunidae were found in Ibiraquera Lagoon. Neohelice granulata Dana, 1851 was... |
| Tipo: Text |
Palavras-chave: Decapoda larvae; Brachyura; Zoea; Estuary. |
| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00597/70923/69163.pdf |
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| Chevillot, Xavier; Pierre, Maud; Rigaud, Arthur; Drouineau, Hilaire; Chaalali, Aurelie; Sautour, Benoit; Lobry, Jeremy. |
| For decades, global climate change has directly and indirectly affected the structure and function of ecosystems. Abrupt changes in biodiversity have been observed in response to linear or sudden modifications to the environment. These abrupt shifts can cause long-term reorganizations within ecosystems, with communities exhibiting new functional responses to environmental factors. Over the last 3 decades, the Gironde estuary in southwest France has experienced 2 abrupt shifts in both the physical and chemical environments and the pelagic community. Rather than describing these shifts and their origins, we focused on the 3 inter-shift periods, describing the structure of the fish community and its relationship with the environment during these periods. We... |
| Tipo: Text |
Palavras-chave: Ecosystem state; Fish diversity; Estuary; Generalised linear mixed models; GLMM; Time series; Shift; Inter-shift periods. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00334/44567/44282.pdf |
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| Lericolais, Gilles; Berne, Serge; Fenies, Hugues. |
| An incised paleovalley offshore the estuary mouth of the Gironde River (Southwest France) was evidenced recently (Comptes Rendus de 1'Academie des Sciences de Paris 326 (1998) 701). Nevertheless its seaward extension to the shelf break was still unknown. New high-resolution geophysical data were acquired on the continental shelf in order to follow the incision until the shelf break. After processing the seismic lines, the shape of the valley was identified and the valley-fill in terms of sequence stratigraphy was interpreted.The valley-fill contains a single sequence corresponding to a fifth-order cycle (20 kyr). The three Systems Tracks described onshore by Alien and Posamentier (Journal of Sedimentary Petrology 63 (1993) 378; SEPM (Society for... |
| Tipo: Text |
Palavras-chave: High resolution seismic data; Estuary; Sequence stratigraphy; Incised valley fill. |
| Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-477.pdf |
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| Andrieux-loyer, Francoise; Philippon, Xavier; Bally, Gabriel; Kerouel, Roger; Youenou, Agnes; Le Grand, Jacqueline. |
| The macrotidal estuary of Penze (Brittany, Western part of the Channel, France) has been subjected to recurrent annual toxic blooms of Alexandrium minutum since 1988. This study aims to specify the phosphorus dynamics and bioavailability in sediments in order to improve our understanding of Alexandrium occurrences. Sediment-P pools and diffusive phosphate fluxes were studied under similar hydrodynamic conditions, in the intermediate estuary in May, June and July 2003 and along the salinity gradient from August 2004 to June 2005. The results highlight a decrease in bioavailable phosphorus (iron and organic bound) from the inner part of the estuary seaward. The ratio of iron-bound phosphorus to iron-oxyhydroxides is lower in the inner and intermediate... |
| Tipo: Text |
Palavras-chave: Sequential extraction; Sediment phosphorus; Pore water; Phosphate fluxes; Estuary; Alexandrium minutum. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4306.pdf |
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| Grasso, Florent; Verney, Romaric; Le Hir, Pierre; Thouvenin, Benedicte; Schulz, Elisabeth; Kervella, Youenn; Fard, I. Khojasteh Pour; Lemoine, J. -p.; Dumas, Franck; Garnier, Valerie. |
| Tidal pumping, baroclinic circulation and vertical mixing are known to be the main mechanisms responsible for the estuarine turbidity maximum (ETM) formation. However, the influence of hydro-meteorological conditions on ETM dynamics is still not properly grasped and requires further investigation to be quantified. Based on a realistic 3-dimensional numerical model of the macrotidal Seine Estuary (France) that accounts for mud and sand transport processes, the objective of this study is to quantify the influence of the main forcing (river flow, tides, waves) on the ETM location and mass changes. As expected, the ETM location is strongly modulated by semidiurnal tidal cycles and fortnightly timescales with a high sensitivity to river flow variations. The ETM... |
| Tipo: Text |
Palavras-chave: Estuary; Mud; Sand; Hydrodynamics; Turbidity maximum; Waves; Measurement; Modeling. |
| Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00416/52770/53638.pdf |
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| Gailhard, Isabelle. |
| Estuaries are areas which, from their structure, their fonctioning, and their localisation, are subject to significant contribution of nutrients. One of the objectif of the RNO, the French network for coastal water quality monitoring, is to assess the levels and trends of nutrient concentrations in estuaries. A linear model was used in order to describe and to explain the total dissolved nitrogen concentration evolution in the three most important estuaries on the Chanel-Atlantic front (Seine, Loire and Gironde). As a first step, the selection of a reliable data set was performed. Then total dissolved nitrogen evolution schemes in estuary environment were graphically studied, and allowed a resonable choice of covariables. The salinity played a major role... |
| Tipo: Text |
Palavras-chave: Nutriments; Estuaire; Loire; Seine; Gironde; Schéma de dilution; Modèle linéaire; Tendance; Nutrients; Estuary; Seine; Loire; Gironde; Dilution schema; Linear mode1; Trend. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00079/19070/16665.pdf |
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| Poirier, Clement; Sauriau, Pierre-guy; Chaumillon, Eric; Bertin, Xavier. |
| Mollusc death assemblages were recovered in 98 subtidal sampling stations on the seafloor of the shallow Pertuis Charentais Sea (Atlantic coast of France). Taxonomic composition and spatial distribution of death assemblages were investigated, as well as their response to sediment grain size (field data), bottom shear stress (coupled tide and wave hydrodynamic modelling), and sediment budget (bathymetric difference map) Results showed that molluscs are likely to be reliable paleoenvironmental indicators since death assemblages were able to acquire ecological changes within years (decadal-scale taphonomic inertia), and live-dead agreement inferred from existing data on living benthic communities was high, except close to river mouths and intertidal mudflats... |
| Tipo: Text |
Palavras-chave: Benthos; Estuary; Holocene; Paleoecology; Sediment budget; Taphonomy. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00017/12814/10260.pdf |
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| Tecchio, Samuele; Rius, Antonio; Dauvin, Jean-claude; Lobry, Jeremy; Lassalle, Geraldine; Morin, Jocelyne; Bacq, Nicolas; Cachera, Marie; Chaalali, Aurelie; Villanueva, Ching-maria; Niquil, Nathalie. |
| Ecological network analysis was applied in the Seine estuary ecosystem, northern France, integrating ecological data from the years 1996 to 2002. The Ecopath with Ecosim (EwE) approach was used to model the trophic flows in 6 spatial compartments leading to 6 distinct EwE models: the navigation channel and the two channel flanks in the estuary proper, and 3 marine habitats in the eastern Seine Bay. Each model included 12 consumer groups, 2 primary producers, and one detritus group. Ecological network analysis was performed, including a set of indices, keystoneness, and trophic spectrum analysis to describe the contribution of the 6 habitats to the Seine estuary ecosystem functioning. Results showed that the two habitats with a functioning most related to a... |
| Tipo: Text |
Palavras-chave: Trophic network; Estuary; Ecological network analysis; Ecopath with Ecosim; Food web; Ecosystem health indicators. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00270/38154/42026.pdf |
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| Registros recuperados: 105 | |
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