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| Registros recuperados: 30 | |
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| Menet-nedelec, Florence; Ropert, Marion; Riou, Philippe; Courtay, Gaelle; Fontaine, Bruno; Francoise, Sylvaine; Jacqueline, Franck; Lesaulnier, Nadine; Louis, Fabienne; Maheux, Frank; Pierre-duplessix, Olivier; Rabiller, Emilie; Schapira, Mathilde; Simon, Benjamin. |
| La stratégie d’échantillonnage optimisée du Réseau Hydrologique Littoral Normand (RHLN) a été approuvée en 2007 par ses partenaires, avec le triple objectif (1) d’observer les niveaux d’eutrophisation et les phénomènes associés pour comprendre leur déclenchement et évolution ; (2) d’évaluer la qualité des eaux selon les indicateurs réglementaires (DCE, OSPAR), et expertiser ces évaluations selon les connaissances actuelles du milieu ; et (3) d’améliorer et publier les connaissances via des projets de recherche, et permettre la validation des modèles. Ce rapport réalise la synthèse des résultats obtenus en 2014, douzième année depuis le début du suivi en Normandie. Le climat de l’année 2014 a été globalement une année chaude, avec un record de la moyenne... |
| Tipo: Text |
Palavras-chave: Abondance; Baie de Seine; Biomasse chlorophyllienne; Bloom; DCE; Écosystème côtier; Éléments de qualité; Eutrophisation; Grille d’évaluation de l’eutrophisation; Hydrologie; Limitation potentielle; Normandie; Nutriments; Phytoplancton; Production primaire; Réseau hydrologique; RHLN; Stocks hivernaux. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00403/51493/52092.pdf |
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| Hoch, Thierry. |
| This paper deals with a model of the pelagic ecosystem in the English Channel The model takes into account nitrogen biogeochemical cycle explicitly and indirectly phosphorus, silicon and carbon ones. The pelagic ecosystem is described precisely, on the one hand with the help of three phytoplanktonic compartments, and the other by considering the microbial food web. Primary production appears to be mainly controlled by stratification and turbidity, except in the Bay of Seine where high terrestrial nutrient inputs generate a sharp enrichment. Moreover, the model allows some general ecological conclusions to be drawn. From the simulation, it appears that inorganic nitrogen in the water column is mainly produced by an intense recycling. In accordance with in... |
| Tipo: Text |
Palavras-chave: Nitrogen fluxes; Primary production; Ecological model; English Channel; Flux d'azote; Production primaire; Modèle écologique; Manche. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/1998/publication-841.pdf |
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| Videau, Christiane; Ryckaert, Mireille; L' Helguen, Stéphane. |
| Phytoplankton distribution and primary productivity were investigated in the Bay of Seine (eastern English Channel, France) in spring and early summer of 1992 and 1994. In 1992, the horizontal distribution of phytoplankton species was determined over the whole Bay of Seine. In 1994, species distribution and primary productivity were studied along the salinity gradient of the Seine plume and in the neighbouring marine waters. Phytoplankton distribution was characterised by the permanent diatom dominance from early spring to early summer. The spring bloom did not occur uniformly over the bay, but was initiated in the marine waters, in the middle of the bay and progressed towards the coast where it developed, in June, in the diluted waters of the Seine plume.... |
| Tipo: Text |
Palavras-chave: Baie de Seine; Production primaire; Phytoplancton; Bay of Seine; Primary productivity; Phytoplankton. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00333/44398/44057.pdf |
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| Christensen, Jp. |
| A diagenetic model of porewater O-2 was used to examine the relationship between organic carbon flux to the sediments and benthic oxygen demand (BOD). The model predicted that the organic carbon influx to sediments balances BOD as long as sediments are oxygenated. The critical rate occurs when O-2 at infinite depth disappears. With influxes exceeding the critical rate, the O-2 flux into the sediments via molecular diffusion can not consume all incoming organic matter, and anaerobic conditions result in BOD underestimating the carbon influx. Given that low rates of deep-sea BOD approximate the carbon influx below 9 g.C.m(-2).y(-1), a significant multilinear regression was found between published BOD, primary productivity (P-p, both in g.C.m(-2).y(-1))(,)... |
| Tipo: Text |
Palavras-chave: Fonds marins; Oxygène; Production primaire; Respiration; Sédiments; Deep-sea; Oxygen; Primary productivity; Respiration; Sediments. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00325/43578/44046.pdf |
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| Eaucea,; Prou, Jean. |
| L'objet de l'étude est de décrire les liens principaux entre l'hydrologie de la Charente et les constats qualitatifs dans le bassin de Marennes, ainsi que l'estimation des flux continentaux, sur la base des données des stations de Fontenelles et de Boyard entre 1977 et 2006. Du fait de l'influence de la marée, il n'est pas possible de mesurer les débits de la Charente dans sa partie aval. Ils ont donc été reconstitués à partir des stations de Saint-Savinien, du pont de Beillant, de Carillon, du Moulin de Chatre, de la Lijardière, de Jarnac, de Vindelle et de Foulpougne, en fonction de la disponibilité et de la fiabilité des données. Les mesures à Fontenelles et Boyard ont été réalisées de façon à disposer d'une gamme variée de situations par rapport au... |
| Tipo: Text |
Palavras-chave: Hydrologie; Flux continentaux; Cycle de marée; Nitrates; Phosphates; Production primaire; Marennes Oléron; Charente. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/00083/19419/17030.pdf |
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| Soletchnik, Patrick. |
| The Marennes Oléron Bay, the main French oyster culture basin, is an estuarine zone which is subject to anthropic pressure. Meteorological parameters such as temperature, insolation, pluviometry determine, for the most part, the water temperature and salinity conditions for each season and control the nutrient fluxes, as well as the primary and secondary production of the basin. The average air temperature (Météo -France) stays around 12.5°C between 1950 and 1980, then rises more than 1°C in 20 years. In those 50 years, average insolation drops from 198 hours to 176 hours, corresponding to an 11% decrease. Seasonal distribution of water inputs shows that spring pluviometry increased by 30% between the 1950's and the last two decades. Precipitations also... |
| Tipo: Text |
Palavras-chave: Ressource trophique; Crassostrea gigas; Production primaire; Bassin Marennes Oléron; Ecosystème. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/acte-3381.pdf |
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| Le Borgne, R; Rodier, M; Le Bouteiller, A; Murray, Jw. |
| Observations made during a "La Nina" situation (April-May 1996) in the equatorial Pacific upwelling, between 165 degrees E and 150 degrees W, show the classic deepening of hydrological isolines from east to west, resulting in zonal gradients for surface temperature and macronutrients. However, contrasting with such a gradient, no clear zonal variation could be seen for integrated planktonic biomasses and carbon fluxes, namely: chlorophyll a, bacterial abundances, particulate organic phosphorus, mesozooplankton ash free dry weight, primary production, and the sinking flux of particulate organic carbon (POC). Moreover, mean values of these parameters along the zonal equatorial transect, are not significantly different from those of a 7-day-long time series... |
| Tipo: Text |
Palavras-chave: Pacifique équatorial; Variabilité zonale; Plancton; Sédimentation de carbone; Production primaire; Equatorial Pacific; Zonal variations; Plankton; Carbon sinking flux; Primary production. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43629/43254.pdf |
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| Cabecadas, L. |
| Biomass and phytoplankton photosynthetic response were studied in the lower Tagus estuary weekly, and related to environmental conditions in February, March and April 1994. The Photosynthesis-Irradiance ((P-I)-I-B) relation was studied based on the light-saturated photosynthesis rate (P(B)m) and the light-limited initial slope (a(B)). The nutrient concentrations observed were high enough to be considered as not limiting phytoplankton growth. Tagus estuary phytoplankton seems, to a certain extent, adapted to high turbid conditions, being able to utilize the low light levels more efficiently, which was translated by high values of a(B) [0.10-0.20 mg C (mg Chl a)(-1) h(-1) (W m(-2))(-1)]; however, light seems to limit phytoplankton production in the water... |
| Tipo: Text |
Palavras-chave: Production primaire; Phytoplancton; Estuaire; Biomasse; Turbidité; Primary production; Phytoplankton; Estuary; Biomass; Turbidity. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43621/43310.pdf |
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| Cantoni, C; Cozzi, S; Pecchiar, I; Cabrini, M; Mozeti, P; Catalano, G; Umani, Sf. |
| Primary production (PP) and, nitrate (QNO(3)) and ammonium (QNH(4)) uptakes were measured together with other environmental parameters from October 1999 to February 2001 in the Gulf of Trieste (N Adriatic Sea). Their trends showed a high variability because of the combined effects of meteorological conditions, water circulation and river discharges. PP ranged from 0.2 to 1.5.9 mumol C dm(-3) d(-1), whereas QNO(3) varied from 0.8 to 442 nmol N dm(-3) d(-1), showing a trend similar to that of carbon basically ascribable to the autotrophic activity. QNH(4) ranged from 20 to 1308 nmol N dm-3 d-' and it reached the highest values during the declining phases of phytoplankton blooms, indicating that bacterial community can also be involved in its uptake.... |
| Tipo: Text |
Palavras-chave: Production primaire; Production nouvelle; Nutriments; Temps de renouvellement; Apports de rivières; Primary production; New production; Nutrients turnover time; Riverine inputs. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00321/43248/42979.pdf |
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| Dussauze, Morgan. |
| Le modèle hydrodynamique/biogéochimique ECO-MARS 30 est appliqué à la Baie de Bourgneuf (mailles des 500 mètres) afin d'une part, de modéliser la production primaire et d'autre part, d'introduire le modèle de croissance de l'huître Crassostrea gigas (Bari lié et al, 1997). Le modèle n'étant muni ni d'un module de remise en suspension du sédiment, ni d'un module permettant de représenter le compartiment microphytobenthique, une approximation (forçage d'une climatologie pour la matière en suspension, utilisation d'un terme source dans la couche de fond pour la chlorophylle) a été effectuée afin de représenter de manière schématique le gradient Nord-Sud de turbidité, les rapides changements de turbidité qui sont mesurés au niveau des bancs ostréicoles au... |
| Tipo: Text |
Palavras-chave: Baie de Bourgneuf; Production primaire; Croissance de l'huître; Modèle mathématique. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/00446/55746/57401.pdf |
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| Registros recuperados: 30 | |
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