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Registros recuperados: 11 | |
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MENDOZA,URSULA; CANDELLA,ROGÉRIO N.; ASSAD,LUIZ P.F.; CASTILLO,FEDERICO V.; AZEVEDO,LAURA; KNOPPERS,BASTIAAN A.; ALBUQUERQUE,ANA LUIZA S.. |
This work addresses the design and configuration of a Eulerian sediment trap mooring array, which was deployed at the shelf edge (zm ≈ 140 m) 80 km off Cabo Frio, SE- Brazil (23° S). The site was subject to interplay between the Tropical Waters (TW) of the Brazil Current (BC), intrusions from the South Atlantic Central Waters (SACW), which are the source of upwelling in the region, and other oceanographic processes. Detailed computations were used to optimize the total weight, buoyancy balance, and maximum acceptable tilt to avoid hydrodynamic bias in the trapping efficiency and array adaptation to the local oceanographic conditions with the assistance of Matlab and Muringa programs and Modular Ocean Model 4.0 (MOM; i.e., to assert the vertical... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Design; Mooring array; Sediment traps; Trap efficiency; Cabo Frio upwelling; SE-Brazil. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000200589 |
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González,H E; Daneri,G; Menschel,E; Marchant,M; Pantoja,S; Hebbeln,D; Barria,C; Vera,R; Iriarte,J. |
Vertical fluxes of particles have been estimated during the last decade in coastal and oceanic systems off central-southern Chile. Free-drifting, cylindrical sediment traps have been deployed below the mixing layer from coastal areas, while automatic, cone-shaped sediment traps have been anchored in deep oceanic areas. Vertical fluxes toward 2300 m depth off Coquimbo were dominated by calcium carbonate (~70 mg m-2 d-1) instead of particulate organic carbon (POC ~7 mg m-2 d-1), where foraminifers (Neogloboquadrina pachyderma) and faecal pellets of Euphausia mucronata and Oikopleura spp, played important roles as vehicles for carbonate and carbon, respectively. In coastal upwelling systems, (i. e. Concepción), the dominant vertical flux was POC, mainly... |
Tipo: Journal article |
Palavras-chave: Particulate organic matter; Fluxes; Oxygen minimum zone; Zooplankton functional groups; Sediment traps; Central Chile. |
Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382006000300007 |
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Heimbuerger, Lars-eric; Cossa, Daniel; Thibodeau, Benoit; Khripounoff, Alexis; Mas, Virginie; Chiffoleau, Jean-francois; Schmidt, Sabine; Migon, Christophe. |
The magnitude and the chronology of anthropogenic impregnation by Hg and other trace metals of environmental concern (V, Cr, Ni, Cu, Zn, Ag, Cd and Pb, including its stable isotopes) in the sediments are determined at the DYFAMED station, a site in the Ligurian Sea (Northwestern Mediterranean) chosen for its supposed open-sea characteristics. The DYFAMED site (VD) is located on the right levee of the Var Canyon turbidite system, at the end of the Middle Valley. In order to trace the influence of the gravity current coming from the canyon on trace metal distribution in the sediment, we studied an additional sediment core (VA) from a terrace of the Var Canyon, and material collected in sediment traps at the both sites at 20 m above sea bottom. The patterns... |
Tipo: Text |
Palavras-chave: Marine sediments; Sediment traps; Mercury; Trace metals; Lead isotopes; Geochronology. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00073/18435/16125.pdf |
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ALBUQUERQUE,ANA LUIZA S.; BELÉM,ANDRÉ L.; ZULUAGA,FRANCISCO J.B.; CORDEIRO,LIVIA G.M.; MENDOZA,URSULA; KNOPPERS,BASTIAAN A.; GURGEL,MARCIO H.C.; MEYERS,PHILIP A.; CAPILLA,RAMSÉS. |
Physical and biogeochemical processes in continental shelves act synergistically in both transporting and transforming suspended material, and ocean dynamics control the dispersion of particles by the coastal zone and their subsequent mixing and dilution within the shelf area constrained by oceanic boundary currents, followed by their gradual settling in a complex sedimentary scenario. One of these regions is the Cabo Frio Upwelling System located in a significantly productive area of Southeastern Brazil, under the control of the nutrient-poor western boundary Brazil Current but also with a wind-driven coastal upwelling zone, inducing cold-water intrusions of South Atlantic Central Water on the shelf. To understand these synergic interactions among... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sediment traps; Bulk geochemical composition; Cabo Frio Upwelling System; Particle flux; Southeastern Brazilian shelf. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000200601 |
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Cailliau, C; Belviso, S; Goutx, M; Bedo, A; Park, Y; Charriaud, E. |
During summer 1994, the production regime at 2 sites located in the Indian sector of the Southern Ocean, one in the Permanent Open Ocean Zone (POOZ) at 52 degrees S, and a second in the Seasonal Ice Zone (SIZ) at 63 degrees S, was dominated by regeneration (0.3 < f-ratio < 0.4). Two time series, each of about 4 d, were performed over pre-determined time intervals of 4 h using a free-floating sediment trap set at 200 m at the 2 sites. Hourly variations of C, N, chlorophyll a (chl a) and its degradation products, taxon-specific pigments, lipid classes and dimethylsulfoniopropionate (DMSP) were measured simultaneously. Measurements in the water column were done during the sediment trap drifting. Fucoxanthin, a typical diatom pigment, was the major... |
Tipo: Text |
Palavras-chave: Antarctic; Austral ocean; Sediment traps; Diel cycles; Phytoplankton; Pigments; Lipids; DMSP; DMS. |
Ano: 1999 |
URL: https://archimer.ifremer.fr/doc/00240/35083/33651.pdf |
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Bernal, G.; Velásquez, A.; Vargas, I.; Agudelo, A.C.; Andrade, C.A.; Domínguez, J.G.; Ricaurte, C.; Mayo, G.. |
To understand sedimentation processes at Salmedina Reef Banks during the annual cycle, three cylindrical sediment traps were installed on the flat top of the reef Banks at mean depth of 8.5 m. Cylinders were collected monthly between July, 2003 and September, 2004. The trap content was analyzed by bulk composition and the composition of biogenic calcareous particles from the sand fraction. Results were compared with environmental parameters of the area trough the same time span. Sedimentological variables were analyzed with emphasis on terrigenous supply and relative percentages of calcareous components related to location and physical parameters. It was found that the totality of sedimentation, terrigenous contribution included, was concentrated during... |
Tipo: Journal Contribution |
Palavras-chave: Reefs; Sediment traps. |
Ano: 2006 |
URL: http://hdl.handle.net/1834/1976 |
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Guieu, C; Roy-barman, M; Leblond, N; Jeandel, C; Souhaut, M; Le Cann, Bernard; Dufour, A; Bournot, C. |
In the framework of the Programme Ocean Multidisciplinaire Meso Echelle (POMME) experiment, a 1.5 year record (February 2001-June 2002) of downward particle flux at 400 m and 1000 m was measured by sediment traps at four moorings located in the northeast Atlantic between 39 degrees-43 degrees N and 17 degrees-19 degrees W. Thorium-230 was used to estimate sediment trap efficiency, revealing values ranging from 18.5 to 55%. The lowest trapping efficiency was observed for the trap having experienced the highest currents. Significant interannual variability between 2001 and 2002 was clearly linked to the differences observed in the mixed layer depth. At some sites, particulate organic carbon (POC) export was higher (up to a factor of 1.6) during summer than... |
Tipo: Text |
Palavras-chave: Sediment traps; Carbon export; Biogenic and lithogenic tracers; Mesoscale circulation; Thorium isotopes. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/00000/10982/7422.pdf |
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Registros recuperados: 11 | |
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