|
|
|
| Registros recuperados: 68 | |
|
| |
|
| |
|
|
| Ruffine, Livio; Ondreas, Helene; Blanc-valleron, Marie-madeleine; Teichert, Barbara M. A.; Scalabrin, Carla; Rinnert, Emmanuel; Birot, Dominique; Croguennec, Claire; Ponzevera, Emmanuel; Pierre, Catherine; Donval, Jean-pierre; Alix, Anne-sophie; Germain, Yoan; Bignon, Laurent; Etoubleau, Joel; Caprais, Jean-claude; Knoery, Joel; Lesongeur, Francoise; Thomas, Bastien; Roubi, Angelique; Legoix, Ludovic Nicolas; Burnard, Pete; Chevalier, Nicolas; Lu, Hailong; Dupre, Stephanie; Fontanier, Christophe; Dissard, Delphine; Olgun, Nazli; Yang, Hailin; Strauss, Harald; Ozaksoy, Volkan; Perchoc, Jonathan; Podeur, Christian; Tarditi, Corinne; Ozbeki, Eyyup; Guyader, Vivien; Marty, Bernard; Madre, David G; Pitel-roudaut, Mathilde; Grall, Celine; Embriaco, Davide; Polonia, Mina; Gasperini, Lucas; Cagatay, M. Namik; Henry, Pierre; Geli, Louis. |
| MarsiteCruise was undertaken in October/November 2014 in the Sea of Marmara to gain detailed insight into the fate of fluids migrating within the sedimentary column and partially released into the water column. The overall objective of the project was to achieve a more global understanding of cold-seep dynamics in the context of a major active strike-slip fault. Five remotely operated vehicle (ROV) dives were performed at selected areas along the North Anatolian Fault and inherited faults. To efficiently detect, select and sample the gas seeps, we applied an original procedure. It combines sequentially (1) the acquisition of ship-borne multibeam acoustic data from the water column prior to each dive to detect gas emission sites and to design the tracks of... |
| Tipo: Text |
Palavras-chave: Acoustic survey; Authigenic carbonates; Biogeochemistry; Chemical analyses; Cold seeps; Dissolved major elements; Fluid seepage; Geology; In situ Raman analysis; Methane; ROV dives. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00433/54434/55783.pdf |
| |
|
|
| Herbert, R. |
| Seasonal data and depth profiles using super(15)N-labelled NO sub(3)u- show that denitrification (77-90% of NO sub(3)u- respired) rather than NO sub(3)u- dissimilation to NH sub(4)u+ was the principal route of nitrate reduction in Kingoodie Bay sediments. Populations of both groups of NO sub(3)u- reducing bacteria were highest in the 0-20 mm horizon in those sediments where highest rates of NO sub(3)u- respiration were recorded (28.56 mu g N.d super(-1) dry wt. sediment super(-1)). Autotrophic nitrification rates shared a marked seasonality with highest rates (0.92 mu g N.d super(-1).g dry wt. sediment super(-1)) occurring during the summer. Maximum populations of autotrophic nitrifying bacteria were also found in the 0-20 mm sediment horizon and these... |
| Tipo: Text |
Palavras-chave: Seasonal variations; Bacteria; Estuaries; Sediment chemistry; Biogeochemistry; Ammonia; Nitrates; Nitrogen cycle. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-971.pdf |
| |
|
| |
|
|
| Peguero, Guille; Sardans, Jordi; Asensio, Dolores; Fernández-martínez, Marcos; Gargallo-garriga, Albert; Grau, Oriol; Llusià, Joan; Margalef, Olga; Márquez, Laura; Ogaya, Romà; Urbina, Ifigenia; Courtois, Elodie A.; Stahl, Clément; Van Langenhove, Leandro; Verryckt, Lore T.; Richter, Andreas; Janssens, Ivan A.; Peñuelas, Josep. |
| Soil fauna is a key control of the decomposition rate of leaf litter, yet its interactions with litter quality and the soil environment remain elusive. We conducted a litter decomposition experiment across different topographic levels within the landscape replicated in two rainforest sites providing natural gradients in soil fertility to test the hypothesis that low nutrient availability in litter and soil increases the strength of fauna control over litter decomposition. We crossed these data with a large dataset of 44 variables characterizing the biotic and abiotic microenvironment of each sampling point and found that microbe-driven carbon (C) and nitrogen (N) losses from leaf litter were 10.1 and 17.9% lower, respectively, in the nutrient-poorest site,... |
| Tipo: Text |
Palavras-chave: Biogeochemistry; Extracellular enzyme activity; Litter decomposition; Nutrients; Soil fauna. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00513/62424/69469.pdf |
| |
|
|
| MACDONELL,SHELLEY A; FITZSIMONS,SEAN J. |
| Cryoconite holes are water-filled depressions that form on glacier surfaces when uneven distributions of sediment cause differential melting to occur. Cryoconite holes are important features of cold glacier systems, as they enhance meltwater generation, enable the development of complex drainage networks and facilitate the growth of microbial communities on the glacier surface. This paper describes the development of a cryoconite hole hydrological network on an Antarctic glacier, and explores the implications for nutrient storage and delivery within the glacier system. Field measurements included measuring the internal dimensions and repeat mapping of cryoconite holes across the glacier surface, and laboratory analysis included cation and anion analysis on... |
| Tipo: Journal article |
Palavras-chave: Biogeochemistry; Drainage system; Glacier hydrology; Meltwater; Solute. |
| Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000400003 |
| |
|
|
| Giraud, Mélanie; Garçon, Véronique; De La Broise, Denis; L'Helguen, Stéphane; Sudre, Joël; Boye, Marie. |
| Installation of an Ocean Thermal Energy Conversion pilot plant (OTEC) off the Caribbean coast of Martinique is expected to use approximately 100,000 m3 h−1 of deep seawater for its functioning. This study examined the potential effects of the cold nutrient-rich deep seawater discharge on the phytoplankton community living in the surface warm oligotrophic waters before the installation of the pilot plant. Numerical simulations of deep seawater upwelled by the OTEC, showed that a 3.0 °C temperature change, considered as a critical threshold for temperature impact, was never reached during an annual cycle on the top 150 m of the water column on two considered sections centered on the OTEC. The thermal effect should be limited, <1 km2 on the area exhibited... |
| Tipo: Text |
Palavras-chave: Marine microbial ecosystem; Biogeochemistry; Modeling; Artificial seawater discharge in situ experiments; Environmental standards. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00507/61867/65935.pdf |
| |
|
|
| Le Traon, Pierre-yves; D'Ortenzio, Fabrizio; Babin, Marcel; Leymarie, Edouard; Marec, Claudie; Pouliquen, Sylvie; Thierry, Virginie; Cabanes, Cecile; Claustre, Hervé; Desbruyeres, Damien; Lacour, Leo; Lagunas, Jose-luis; Maze, Guillaume; Mercier, Herle; Penkerc'H, Christophe; Poffa, Noe; Poteau, Antoine; Prieur, Louis; Racape, Virginie; Randelhoff, Achim; Rehm, Eric; Schmechtig, Catherine Marie; Taillandier, Vincent; Wagener, Thibaut; Xing, Xiaogang. |
| Argo, the international array of profiling floats, 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 the French “Investissements d’Avenir” Equipex program. The objectives of NAOS were to consolidate the French contribution to Argo’s core mission (global temperature and salinity measurements down to 2000 m), and also 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 how NAOS has met its objectives. The project significantly boosted France’s contribution to Argo’s core mission by... |
| Tipo: Text |
Palavras-chave: Profiling floats; Deep ocean; Biogeochemistry; Mediterranean Sea; Arctic; Atlantic; Argo. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00654/76584/77729.pdf |
| |
|
|
| 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 |
| |
|
|
| PARRON, L. M.; BUSTAMANTE, M. M. da C.; PRADO, C. L. C.. |
| RESUMO: Em função do gradiente de umidade na topografia do terreno e de diferenças entre estações seca e chuvosa, o presente trabalho teve como objetivos quantificar a produção anual e a disponibilidade de nutrientes (N, P, K, Ca, Mg E S) na serapilheira e estimar a eficiência do uso de nutrientes em uma Mata de Galeria. O experimento foi estabelecido numa área de 100 x 100 m da Mata de Galeria do Córrego Pitoco, na Reserva Ecológica do IBGE, DF (15°56'41"S e 47°56'07"W). Como delineamento experimental, foram estabelecidas três linhas de amostragem paralelas ao córrego, distantes 45 m entre si, denominadas, respectivamente, comunidades úmida (na margem do córrego), intermediárias e seca (adjacentes a uma área de Cerrado Típico). A produção de serapilheira... |
| Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) |
Palavras-chave: Biogeoquímica; Ciclagem de nutriente; Eficiência de nutriente; Savana; Productivity; Nutrient cycling; Litterfall; Nutrient efficiency.; Disponibilidade de Nutriente; Floresta Tropical; Produtividade.; Biogeochemistry; Tropical forests.; Savannas. |
| Ano: 2004 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/569203 |
| |
|
|
| Pagès, Rémi; Baklouti, Melika; Barrier, Nicolas; Ayache, Mohamed; Sevault, Florence; Somot, Samuel; Moutin, Thierry. |
| The Mediterranean region has been shown to be particularly exposed to climate change, with observed trends that are more pronounced than the global tendency. In forecast studies based on a RCP 8.5 scenario, there seems to be a consensus that, along with an increase in temperature and salinity over the next century, a reduction in the intensity of deep-water formation and a shallowing of the mixed layer [especially in the North-Western Mediterranean Sea (MS)] are expected. By contrast, only a few studies have investigated the effects of climate change on the biogeochemistry of the MS using a 3D physical/biogeochemical model. In this study, our aim was to explore the impact of the variations in hydrodynamic forcing induced by climate change on the... |
| Tipo: Text |
Palavras-chave: Mediterranean Sea; Coupled hydrodynamic-biogeochemical model; RCP scenario; Biogeochemistry; Climate change. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00659/77073/78385.pdf |
| |
|
|
| Rousseau, Tristan C. C.; Sonke, Jeroen E.; Chmeleff, Jerome; Van Beek, Pieter; Souhaut, Marc; Boaventura, Geraldo; Seyler, Patrick; Jeandel, Catherine. |
| Rare earth element (REE) concentrations and neodymium isotopic composition (epsilon Nd) are tracers for ocean circulation and biogeochemistry. Although models suggest that REE release from lithogenic sediment in river discharge may dominate all other REE inputs to the oceans, the occurrence, mechanisms and magnitude of such a source are still debated. Here we present the first simultaneous observations of dissolved (< 0.45 mu m), colloidal and particulate REE and eNd in the Amazon estuary. A sharp drop in dissolved REE in the low-salinity zone is driven by coagulation of colloidal matter. At mid-salinities, total dissolved REE levels slightly increase, while epsilon Nd values are shifted from the dissolved Nd river endmember (- 8.9) to values typical of... |
| Tipo: Text |
Palavras-chave: Earth sciences; Biogeochemistry; Oceanography. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00298/40952/40046.pdf |
| |
|
| |
|
|
| 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 |
| |
|
|
| Hoppe, H. |
| Extracellular enzymes mediate the decomposition of polymeric organic compounds in natural waters. In many cases these enzymes comprise a component linked to the bacterial fraction of the aquatic community and react in close association with these cells. An annual survey of microbial activities in a brackish water fjord exhibited an excellent correlation between V sub(m) of proteases (ability to split the substrate analogue methylumbelliferyl-leucine) and V sub(m) as well as T sub(R) for leucine uptake by microorganisms. Hydrolysis rates (H sub(R)) for the decomposition of naturally occurring competitive substrate analogues of the model substrates (methylumbelliferyl-(MUF)-leucine, MUF- alpha -D-glucose, MUF-N-acetyl-glucosamine, MUF-phosphate) drastically... |
| Tipo: Text |
Palavras-chave: Biogeochemistry; Fjords; Bacteria; Brackishwater environment; Seasonal variations; Dissolved organic matter; Interspecific relationships; Hydrolysis; Enzymes. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-952.pdf |
| |
|
| |
|
|
| Smith, Shawn R.; Alory, Gaël; Andersson, Axel; Asher, William; Baker, Alex; Berry, David I.; Drushka, Kyla; Figurskey, Darin; Freeman, Eric; Holthus, Paul; Jickells, Tim; Kleta, Henry; Kent, Elizabeth C.; Kolodziejczyk, Nicolas; Kramp, Martin; Loh, Zoe; Poli, Paul; Schuster, Ute; Steventon, Emma; Swart, Sebastiaan; Tarasova, Oksana; Petit De La Villeon, Loic; Vinogradova-shiffer, Nadya. |
| The role ships play in atmospheric, oceanic, and biogeochemical observations is described with a focus on measurements made near the ocean surface. Ships include merchant and research vessels; cruise liners and ferries; fishing vessels; coast guard, military, and other government-operated ships; yachts; and a growing fleet of automated surface vessels. The present capabilities of ships to measure essential climate/ocean variables and the requirements from a broad community to address operational, commercial, and scientific needs are described. The authors provide a vision to expand observations needed from ships to understand and forecast the exchanges across the ocean–atmosphere interface. The vision addresses (1) recruiting vessels to improve both... |
| Tipo: Text |
Palavras-chave: Ships; Observations; Meteorology; Physical oceanography; Biogeochemistry; Data management; Climatology. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00509/62042/66191.pdf |
| |
|
|
| Irion, Solène; Christaki, Urania; Berthelot, Hugo; L’helguen, Stéphane; Jardillier, Ludwig. |
| Phytoplankton is composed of a broad-sized spectrum of phylogenetically diverse microorganisms. Assessing CO2-fixation intra- and inter-group variability is crucial in understanding how the carbon pump functions, as each group of phytoplankton may be characterized by diverse efficiencies in carbon fixation and export to the deep ocean. We measured the CO2-fixation of different groups of phytoplankton at the single-cell level around the naturally iron-fertilized Kerguelen plateau (Southern Ocean), known for intense diatoms blooms suspected to enhance CO2 sequestration. After the bloom, small cells (<20 µm) composed of phylogenetically distant taxa (prymnesiophytes, prasinophytes, and small diatoms) were growing faster (0.37 ± 0.13 and 0.22 ± 0.09... |
| Tipo: Text |
Palavras-chave: Biogeochemistry; Microbial ecology; Stable isotope analysis. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00684/79595/82286.pdf |
| |
|
|
| 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 |
| |
| Registros recuperados: 68 | |
|
|
|
