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Registros recuperados: 83 | |
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Riva, A.; Lelong, P.. |
The lagoon of Brusc located on the Mediterranean coast (VarFrance) is subjected to climatic and hydrologic particular conditions. The low values observed for nutrient into the sea water affect the evolution of phytoplankton. Thus chlorophyll concentration measured in the lagoon give an annual average of 0.42 mg. m-3 . The growth of two bivalves species : Cerastoderma glaucum and Venerupis semidecussata was compared between two stations where one population of each species are implanted. The culture of this molluscs is made in the lagoon and in outdoor pound dug on the old salt-pan near at hand. In the pound, subjected to natural climatic conditions, a great growth is noted for this two species. The growth rate appear better than the populations of the... |
Tipo: Text |
Palavras-chave: Lagune méditerranéenne; Production primaire; Bivalves; Croissance; Mediterranean Lagoon; Primary production; Bivalves; Growth. |
Ano: 1979 |
URL: http://archimer.ifremer.fr/doc/00306/41674/40883.pdf |
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Rochelle-newall, Emma. J.; Winter, Christian; Barrón, Cristina; Borges, Alberto V.; Duarte, Carlos M.; Elliott, Mike; Frankignoulle, Michel; Gazeau, Frederic; Middelburg, Jack J.; Pizay, Marie-dominique; Gattuso, Jean-pierre. |
Knowing the metabolic balance of an ecosystem is of utmost importance in determining whether the system is a net source or net sink of carbon dioxide to the atmosphere. However, obtaining these estimates often demands significant amounts of time and manpower. Here we present a simplified way to obtain an estimation of ecosystem metabolism. We used artificial neural networks (ANNs) to develop a mathematical model of the gross primary production to community respiration ratio (GPP:CR) based on input variables derived from three widely contrasting European coastal ecosystems (Scheldt Estuary, Randers Fjord, and Bay of Palma). Although very large gradients of nutrient concentration, light penetration, and organic-matter concentration exist across the sites,... |
Tipo: Text |
Palavras-chave: Artificial neural networks; Coastal ecosystems; Metabolic balance; Primary production; Respiration. |
Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00247/35857/34378.pdf |
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Boulart, C; Flament, Pierre; Gentilhomme, V; Deboudt, K; Migon, C; Lizon, F; Schapira, M; Lefebvre, Alain. |
Wet atmospheric deposition of dissolved N, P and Si species is studied in well-mixed coastal ecosystem to evaluate its potential to stimulate photosynthetic activities in nutrient-depleted conditions. Our results show that, during spring, seawater is greatly depleted in major nutrients: Dissolved Inorganic Nitrogen (DIN), Dissolved Inorganic Phosphorus (DIP) and Silicic acid (Si), in parallel with an increase of phytoplanktonic biomass. In spring (March-May) and summer (June-September), wet atmospheric deposition is the predominant source (> 60%, relative to riverine contribution) for nitrates and ammonium inputs to this N-limited coastal ecosystem. During winter (October-February), riverine inputs of DIN predominate (> 80%) and are annually the most... |
Tipo: Text |
Palavras-chave: Strait of Dover; Nutrient cycles; River plumes; Atmospheric deposition; Coastal zone; Primary production. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2007.pdf |
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PETRUCIO, M. M.; BARBOSA, F. A. R.; FURTADO, A. L. dos S.. |
The purpose of this study was to measure the phytoplankton production (PP) and bacterial production (BP) simultaneously in seven lakes in the middle Rio Doce basin (southeast Brazil) during the dry and the rainy seasons. Limnological monitoring was conducted from 1999 to 2001 as well as both PP (radioactive carbon fixation) and BP (3H-Leucine incorporation) in four specific depths (100%, 10%, 1% of incident radiation, and aphotic zone). Furthermore, trophic state of the lakes was analyzed, considering the index proposed by Salas and Martino (1991) and Carlson (1977). In general, some parameters increased during the rainy season such as pH, conductivity, chlorophyll and total nitrogen. In the period of 1999/2000, the rain caused PP reduction in the lakes,... |
Tipo: Artigo de periódico |
Palavras-chave: Primary production; Trophic state.; Bacterial secondary production; Lakes; Phytoplankton; Bacterioplankton.. |
Ano: 2006 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1009158 |
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Chust, Guillem; Allen, J. Icarus; Bopp, Laurent; Schrum, Corinna; Holt, Jason; Tsiaras, Kostas; Zavatarelli, Marco; Chifflet, Marina; Cannaby, Heather; Dadou, Isabelle; Daewel, Ute; Wakelin, Sarah L.; Machu, Eric; Pushpadas, Dhanya; Butenschon, Momme; Artioli, Yuri; Petihakis, Georges; Smith, Chris; Garcon, Veronique; Goubanova, Katerina; Le Vu, Briac; Fach, Bettina A.; Salihoglu, Baris; Clementi, Emanuela; Irigoien, Xabier. |
Ocean warming can modify the ecophysiology and distribution of marine organisms, and relationships between species, with nonlinear interactions between ecosystem components potentially resulting in trophic amplification. Trophic amplification (or attenuation) describe the propagation of a hydroclimatic signal up the food web, causing magnification (or depression) of biomass values along one or more trophic pathways. We have employed 3-D coupled physical-biogeochemical models to explore ecosystem responses to climate change with a focus on trophic amplification. The response of phytoplankton and zooplankton to global climate-change projections, carried out with the IPSL Earth System Model by the end of the century, is analysed at global and regional basis,... |
Tipo: Text |
Palavras-chave: Ecosystem model; Food web; Plankton; Primary production; Sea warming; Trophic amplification. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00188/29966/28481.pdf |
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Martínez Canals, M.; Montalvo, J.F.; Miravet, M.E.; Lugioyo, M.; Loza, S.; Pérez, R.; García, I.; Rodríguez, A.; Cesar, M.E.; Esponda, S.; Sánchez, M.; Delgado, V.. |
The anthropogenic affectation was evaluated on the coast N of the Gulf of Batabanó in May 2003 (corresponding to the provinces of Matanzas and Havana), in areas located in the line of the coast. The results were compared with the historical information of the sector. In the coast N and the Ensenada of the Broa, the parameters oxygen saturation, DBO5 and DQO showed characteristic high values of eutrofication. The biggest contribution in the Cianoficies was in the near coastal areas to sources of organic contamination. In the case of the nutrients they show specific data of mesothrofic waters with tendency to the eutrofization and the silts presented a high affectation for toxic metals. The area near to Guanímar is distinguished to present conditions of... |
Tipo: Proceedings Paper |
Palavras-chave: Phytoplankton; Water quality; Primary production; Chemistry; Environmental monitoring; Phytoplankton; Water quality; Primary production; Chemistry; Environmental monitoring; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_16061; Http://aims.fao.org/aos/agrovoc/c_34329; Http://aims.fao.org/aos/agrovoc/c_1522; Http://aims.fao.org/aos/agrovoc/c_37876. |
Ano: 2006 |
URL: http://hdl.handle.net/1834/2172 |
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Mancera-P., J.E.. |
Un estudio ecológico de la salina marina Pozos Colorados se llevó a cabo entre enero y agosto de 1987. Si bien las dos estaciones de muestreo presentaron amplias diferencias entre si; en general la dinámica del ecosistema dependió aparentemente de la salinidad, la cual varió entre 75 y 341 °/oo; su incremento y la disminución del nivel de agua, al parecer generaron aumento de la temperatura y disminución del oxígeno disuelto, con rangos de 26,3 y 41 °C para la primera y O y 5,4 mg/l para el segundo. Aunque en promedio el pH fue neutro (7,5), este sistema reductor, caracterizado además por abundante materia orgánica, generó en ocasiones una ligera acidez (6,7). La producción primaria neta fue negativa en la mayoría de los casos, como resultado de una... |
Tipo: Journal Contribution |
Palavras-chave: Salinity effects; Ecosystems; Temperature effects; Primary production; Population structure; Ecology; Ecosystems; Primary production; Population structure; Ecology; Http://aims.fao.org/aos/agrovoc/c_2482; Http://aims.fao.org/aos/agrovoc/c_34329; Http://aims.fao.org/aos/agrovoc/c_6115; Http://aims.fao.org/aos/agrovoc/c_2467. |
Ano: 1990 |
URL: http://hdl.handle.net/1834/3887 |
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Henley, Sian F.; Cavan, Emma L.; Fawcett, Sarah E.; Kerr, Rodrigo; Monteiro, Thiago; Sherrell, Robert M.; Bowie, Andrew R.; Boyd, Philip W.; Barnes, David K. A.; Schloss, Irene R.; Marshall, Tanya; Flynn, Raquel; Smith, Shantelle. |
The Southern Ocean plays a critical role in regulating global climate as a major sink for atmospheric carbon dioxide (CO2), and in global ocean biogeochemistry by supplying nutrients to the global thermocline, thereby influencing global primary production and carbon export. Biogeochemical processes within the Southern Ocean regulate regional primary production and biological carbon uptake, primarily through iron supply, and support ecosystem functioning over a range of spatial and temporal scales. Here, we assimilate existing knowledge and present new data to examine the biogeochemical cycles of iron, carbon and major nutrients, their key drivers and their responses to, and roles in, contemporary climate and environmental change. Projected increases in... |
Tipo: Text |
Palavras-chave: Southern Ocean; Biogeochemistry; Primary production; Iron; Nutrients; Carbon; Ecosystem; Ocean acidification. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00676/78831/81113.pdf |
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Civitarese, G; Crise, A; Crispi, G; Mosetti, R. |
In this work the description of the interaction between the general circulation and the nitrogen cycle in the Ionian Sea is considered. Firstly, an analysis is made of nitrate data collected during POEM-BC cruises in October 1991 and April 1992; then a numerical experiment based on a coupled hydrodynamic ecomodel is presented. The model results relative to the periods corresponding to the cruises are discussed. The ecomodel is climatological and represents an aggregated description of the nitrogen cycle in terms of inorganic nitrogen, phytoplankton and detritus. The numerical results as nitrogen distributions, fluxes and primary production are presented. A strong dependence of nitrogen distribution on circulation emerges both from the observational data... |
Tipo: Text |
Palavras-chave: Ionian Sea; Nitrogen cycle; General circulation; Ecomodel; Primary production. |
Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00096/20729/18366.pdf |
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Huret, Martin; Dadou, Isabelle; Dumas, Franck; Lazure, Pascal; Garcon, Véronique. |
A coupled three-dimensional physical-biogeochemical model was developed in order to simulate the ecological functioning of the Rio de la Plata estuary and plume. The biogeochemical model reproduces the nitrogen cycle between five compartments: dissolved inorganic nitrogen, phytoplankton, zooplankton, detritus and dissolved organic nitrogen. The coupling is tested in seasonal climatological configurations and for the particular year 1999. The circulation is forced with Parana and Uruguay rivers discharges, NCEP wind and tide. The biogeochemical model includes loads of inorganic and organic nitrogen from both rivers. The model reproduces the correct tidal amplitudes in the estuary, as well as the most outstanding features of the observed horizontal and... |
Tipo: Text |
Palavras-chave: Rio de la Plata; SeaWiFS; Primary production; Chlorophyll; River plumes; Biogeochemical modelling; Physical. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-334.pdf |
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Registros recuperados: 83 | |
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