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| Registros recuperados: 68 | |
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| Alvarez, M.; Tanhua, T.; Brix, H.; Lo Monaco, C.; Metzl, N.; Mcdonagh, E. L.; Bryden, H. L.. |
| Within the Subantarctic Mode Water (SAMW) density level, we study temporal changes in salinity, nutrients, oxygen and TTD (Transit Time Distribution) ages in the western (W) and eastern (E) subtropical gyre of the Indian Ocean (IO) from 1987 to 2002. Additionally, changes in Total Alkalinity (TA) and Dissolved Inorganic Carbon (DIC) are evaluated between 1995 and 2002. The mechanisms behind the detected changes are discussed along with the results from a hindcast model run (Community Climate System Model). The increasing salinity and decreasing oxygen trends from 1960 to 1987 reversed from 1987 to 2002 along the gyre. In the W-IO a decreasing trend in TTD ages points to a faster delivery of SAMW, thus less biogenic matter remineralization, explaining the... |
| Tipo: Text |
Palavras-chave: Indian Ocean; Subantarctic Mode Water; Biogeochemistry. |
| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00253/36400/34942.pdf |
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| André, Xavier; Le Traon, Pierre-yves; Le Reste, Serge; Dutreuil, Vincent; Leymarie, Edouard; Malardé, Damien; Marec, Claudie; Sagot, Jérôme; Amice, Martin; Babin, Marcel; Claustre, Hervé; David, Arnaud; D’ortenzio, Fabrizio; Kolodziejczyk, Nicolas; Lagunas, José Luis; Le Menn, Marc; Moreau, Bertrand; Nogré, David; Penkerc’h, Christophe; Poteau, Antoine; Renaut, Corentin; Schaeffer, Christophe; Taillandier, Vincent; Thierry, Virginie. |
| The international array of profiling floats known as Argo is a major component of the global ocean- and climate-observing system. In 2010, the NAOS (Novel Argo Observing System) project was selected as part of France’s Equipex “Investissement d’Avenir” program. The objectives of NAOS were to consolidate the French contribution to the Argo core mission (global temperature and salinity measurements down to 2,000 m) as well as to develop the future generation of French Argo profiling floats and prepare the next phase of the Argo program with an extension to the deep ocean (Deep-Argo), biogeochemistry (BGC-Argo) and polar seas. This paper summarizes the main technological advances and at-sea validations carried out as part of NAOS: development of a deep (4,000... |
| Tipo: Text |
Palavras-chave: Ocean; Argo; Global observing system; Profiling float; Deep; Biogeochemistry; Under-ice; Float technology. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00658/77029/78314.pdf |
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| Aumont, Olivier; Belviso, Sauveur; Monfray, Patrick. |
| [1] A global model for surface dimethylsulfide (DMS) and particulate dimethylsulfoniopropionate (DMSP) (pDMS) distributions is presented. The main goals of this work were to be able to predict the regional distribution of the air-sea fluxes of DMS and to predict eventually their future evolution with climate change. Diagnostic relationships have been established from data sets obtained during the ALBATROSS and EUMELI cruises carried out in the Atlantic Ocean. These equations nonlinearly relate DMS and pDMSP concentrations to chlorophyll concentrations and to the trophic status of surface waters. This model has been embedded in the global ocean carbon cycle model Institut Pierre et Simon Laplace-Ocean Carbon Cycle Model version 2 (ISPL-OCCM2), a simple... |
| Tipo: Text |
Palavras-chave: Ocean; Biogeochemistry; Ecosystem modeling; DMS; Global. |
| Ano: 2002 |
URL: https://archimer.ifremer.fr/doc/00223/33448/31824.pdf |
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| Ayata, Sakina-dorothee; Irisson, Jean-olivier; Aubert, Anais; Berline, Leo; Dutay, Jean-claude; Mayot, Nicolas; Nieblas, Anne-elise; D'Ortenzio, Fabrizio; Palmieri, Julien; Reygondeau, Gabriel; Rossi, Vincent; Guieu, Cecile. |
| Regionalisation aims at delimiting provinces within which physical conditions, chemical properties, and biological communities are reasonably homogeneous. This article proposes a synthesis of the many recent regionalisations of the open-sea regions of the Mediterranean Sea. The nine studies considered here defined regions based on different, and sometimes complementary, criteria: dynamics of surface chlorophyll concentration, ocean currents, three-dimensional hydrological and biogeochemical properties, or the distribution of organisms. Although they identified different numbers and patterns of homogeneous regions, their compilation in the epipelagic zone identifies nine consensus frontiers, eleven consensus regions with relatively homogeneous conditions,... |
| Tipo: Text |
Palavras-chave: Mediterranean Sea; Regionalisation; Biogeochemistry; Circulation; Mesoscale features; Epipelagic ocean; Management; Spatial planning. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00405/51673/52221.pdf |
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| Barrales Brito, Edgar. |
| El mantillo y horizontes de fermentación (CF) es un reservorio dinámico de carbono (C) en suelos forestales. Las metodologías que cuantifican la emisión de CO2 por la descomposición son escasas y requieren periodos largos de medición. Se requieren métodos para poder generar información de la emisión de CO2 de éstas capas orgánicas en tiempos cortos de medición. Los objetivos fueron: generar un protocolo para la medición de la emisión de CO2 por la descomposición de mantillo y CF con un respirómetro manométrico (OxiTop ®). Medir los reservorios de C de mantillo y CF de bosques con diferentes condiciones. Medir la emisión de CO2 del mantillo y CF y las tasas de descomposición con un respirómetro. Analizar las características químicas de los mantillos y... |
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Palavras-chave: Biogeoquímica; Emisión de CO2; Respirometría; Materia orgánica; Bosques; Biogeochemistry; CO2 emissions; Respirometry; Organic matter; Forest; Edafología; Maestría. |
| Ano: 2013 |
URL: http://hdl.handle.net/10521/2096 |
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| Bertoni, R. |
| The radiochemical methods proposed for evaluating heterotrophic activity in waters have been severely criticized in recent years because they are not considered to be sufficiently realistic. Thus, the possibility of directly measuring the heterotrophic consumption of naturally occurring Organic Carbon (OC) in fresh water samples incubated under controlled conditions has been evaluated. The analytical performances of two OC analyzers utilizable for this purpose are discussed here, and some examples of the results obtained by the direct measurement of OC consumption are presented. The consumption rates thus measured ranged from 11.6 to 50.2 mu gC/ 1.h. Although the technique discussed here is less sensitive than radiochemical methods, the few assumptions... |
| Tipo: Text |
Palavras-chave: Biogeochemistry; Microbiology; Carbon cycle; Organic carbon; Water; Heterotrophic organisms; Analytical techniques. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-950.pdf |
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| Breviere, Emilie H. G.; Bakker, Dorothee C. E.; Bange, Hermann W.; Bates, Timothy S.; Bell, Thomas G.; Boyd, Philip W.; Duce, Robert A.; Garcon, Veronique; Johnson, Martin T.; Law, Cliff S.; Marandino, Christa A.; Olsen, Are; Quack, Birgit; Quinn, Patricia K.; Sabine, Christopher L.; Saltzman, Eric S.. |
| The domain of the surface ocean and lower atmosphere is a complex, highly dynamic component of the Earth system. Better understanding of the physics and biogeochemistry of the air-sea interface and the processes that control the exchange of mass and energy across that boundary define the scope of the Surface Ocean-Lower Atmosphere Study (SOLAS) project. The scientific questions driving SOLAS research, as laid out in the SOLAS Science Plan and Implementation Strategy for the period 2004-2014, are highly challenging, inherently multidisciplinary and broad. During that decade, SOLAS has significantly advanced our knowledge. Discoveries related to the physics of exchange, global trace gas budgets and atmospheric chemistry, the CLAW hypothesis (named after its... |
| Tipo: Text |
Palavras-chave: Ocean; Atmosphere; Processes; Biogeochemistry; Flux; Climate. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00293/40405/38964.pdf |
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| Carroll, D.; Menemenlis, D.; Adkins, J. F.; Bowman, K. W.; Brix, H.; Dutkiewicz, S.; Fenty, I.; Gierach, M. M.; Hill, C.; Jahn, O.; Landschutzer, P.; Lauderdale, J. M.; Liu, J.; Manizza, M.; Naviaux, J. D.; Roedenbeck, C.; Schimel, D. S.; Van Der Stocken, T.; Zhang, H.. |
| Quantifying variability in the ocean carbon sink remains problematic due to sparse observations and spatiotemporal variability in surface ocean pCO(2). To address this challenge, we have updated and improved ECCO-Darwin, a global ocean biogeochemistry model that assimilates both physical and biogeochemical observations. The model consists of an adjoint-based ocean circulation estimate from the Estimating the Circulation and Climate of the Ocean (ECCO) consortium and an ecosystem model developed by the Massachusetts Institute of Technology Darwin Project. In addition to the data-constrained ECCO physics, a Green's function approach is used to optimize the biogeochemistry by adjusting initial conditions and six biogeochemical parameters. Over seasonal to... |
| Tipo: Text |
Palavras-chave: Ocean modeling; Biogeochemistry; Ocean carbon cycle; Data assimilation; Air‐ Sea CO2 flux; Ecosystem model. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00676/78824/81108.pdf |
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| Conway, T. M.; John, S. G.; Lacan, F.. |
| Intercomparison of trace metal data is a key aspect of the International GEOTRACES program, allowing data from multiple laboratories and countries to be combined to produce high-resolution datasets for the oceans. The use of crossover stations by the GEOTRACES program provides the opportunity both for comparison of analytical techniques and assessment of temporal variability in the cycling of trace metals such as iron (Fe). Here, we present the first comparison of dissolved Fe stable isotope ratio (δ56Fe; relative to IRMM-014) profiles in the oceans, from re-occupations of three locations in the Atlantic Ocean; (1) the Bermuda Atlantic Time Series Station (31.75°N 64.17°W) during the U.S. GEOTRACES IC1 cruise (June 2008) and the U.S. GEOTRACES GA03 cruise... |
| Tipo: Text |
Palavras-chave: Trace metals; GEOTRACES; Biogeochemistry; Intercomparison. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00332/44330/43932.pdf |
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| Deborde, Jonathan; Marchand, Cyril; Molnar, Nathalie; Della Patrona, Luc; Meziane, Tarik. |
| In mangrove ecosystems, strong reciprocal interactions exist between plant and substrate. Under semi-arid climate, Rhizophora spp. are usually predominant, colonizing the seashore, and Avicennia marina develops at the edge of salt-flats, which is the highest zone in the intertidal range. Along this zonation, distribution and speciation of C, Fe, S, N, and P in sediments and pore-waters were investigated. From the land-side to the sea-side of the mangrove, sediments were characterized by I/ increase in: (i) water content; (ii) TOC; (iii) mangrove-derived OM; II/ and decrease in: (i) salinity; (ii) redox; (iii) pH; (iv) solid Fe and solid P. Beneath Avicennia and Rhizophora, TS accumulated at depth, probably as a result of reduction of iron oxides and... |
| Tipo: Text |
Palavras-chave: Mangrove; Zonation; Biogeochemistry; New Caledonia. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00251/36252/34802.pdf |
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| Dulaquais, Gabriel; Boye, Marie; Middag, Rob; Owens, Stephanis; Puigcorbe, Viena; Buesseler, Ken; Masque, Pere; De Baar, Hein J. W.; Carton, Xavier. |
| Dissolved cobalt (DCo; <0.2 µm; 14 to 93 pM) and the apparent particulate cobalt (PCo; >0.2 µm; <1 to 15 pM) were determined in the upper water column (<1000 m) of the western Atlantic Ocean along the GEOTRACES-A02 section (64°N to 50°S). The lowest DCo concentrations, typical of a nutrient-type distribution were observed in surface waters of the subtropical domains. Strong linear relationships between DCo and phosphate (P) as well as meridional gradients of decreasing DCo from high latitudes were characterized and both linked to the Co biological requirement. External sources such as the Amazon and the atmospheric deposition were found to contribute significantly (>10%) to the DCo stock of the mixed layer in the equatorial and north... |
| Tipo: Text |
Palavras-chave: Cobalt; Biogeochemistry; Atlantic Ocean; Chemical Oceanography; GEOTRACES. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00241/35222/33732.pdf |
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| Fernex, F.; Ben Mammou, A.; Added, A.; Abdeljaoued, S.; Essonni, N.. |
| The general current of the Gulf of Tunis are dependent of the general Mediterranean current. This last divides to the level of the Gulf of Tunis in two branches; a first connects by pass west coasts of the gulf while the second branch crosses the centre of the gulf with a NNW - SSE direction. The passage of this second branch of the general current creates a central zone characterised by a sediment relatively sandier than what surrounds it and controls the distribution of the different metallic elements that have for main origin the Oued Mejerda. The metallic elements here analyzed are the Fe, Zn, Ni, Co, Cu and Pb. Their concentrations vary respectively between 0,5. and 1,6%; 279 and 447 ppm; 39 and 67 ppm; 20 and 34 ppm; 9 and 20 and between 56 and 142... |
| Tipo: Journal Contribution |
Palavras-chave: Sediments; Biogeochemistry. |
| Ano: 2003 |
URL: http://hdl.handle.net/1834/1116 |
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| Registros recuperados: 68 | |
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