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| Registros recuperados: 165 | |
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| Abrantes, F; Moita, Mt. |
| Diatom and coccolithophorid abundance and diatom assemblage composition found in the water column along the Portuguese margin, during upwelling and non-upwelling conditions, are compared to the distribution patterns observed in the recent sediments from the same area. The water column results indicate a one order of magnitude increase in phytoplankton biomass during upwelling conditions (summer). with diatoms being the most important contributors. Coccolithophorids, on the contrary, dominate the phytoplankton in winter (non-upwelling). The comparison of the upwelling and non-upwelling spatial distribution of these phytoplankton groups to their sedimentary record reveals the sediment record as a reflection of the upwelling situation, preserving most of its... |
| Tipo: Text |
Palavras-chave: Upwelling; Portugal; Diatomée; Colonne d’eau; Sédiment; Upwelling; Portugal; Diatom; Water column; Sediment. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43613/43915.pdf |
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| Freslon, Nicolas; Bayon, Germain; Toucanne, Samuel; Bermell, Sylvain; Bollinger, Claire; Chéron, Sandrine; Etoubleau, Joel; Germain, Yoan; Khripounoff, Alexis; Ponzevera, Emmanuel; Rouget, Marie Laure. |
| We report rare earth element (REE) and neodymium (Nd) isotope data for the organic fraction of sediments collected from various depositional environments, i.e. rivers (n=25), estuaries (n=18), open-ocean settings (n=15), and cold seeps (n=12). Sedimentary Organic Matter (SOM) was extracted using a mixed hydrogen peroxide/nitric acid solution (20%-H2O2 – 0.02M-HNO3), after removal of carbonate and oxy-hydroxide phases with dilute hydrochloric acid (0.25M-HCl). A series of experimental tests indicate that extraction of sedimentary organic compounds using H202 may be complicated occasionally by partial dissolution of sulphide minerals and residual carbonates. However, this contamination is expected to be minor for REE because measured concentrations in H2O2... |
| Tipo: Text |
Palavras-chave: Organic matter; Rare earth elements; REE; Neodymium isotopes; ΕNd; Sediment; Boundary Exchange; Paleoceanography. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00191/30250/28682.pdf |
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| Dou, Yanguang; Yang, Shouye; Liu, Zhenxia; Clift, Peter D.; Yu, Hua; Berne, Serge; Shi, Xuefa. |
| The Okinawa Trough is a natural laboratory for the study of later Quaternary land-ocean interaction and paleoenvironmental changes. In this study we reconstruct the evolution of clay mineral assemblages in Core DGKS9604 retrieved from the central Okinawa Trough. Illite dominates the clay mineral compositions, with average contents above 60%. Clay mineral evolution since 28 ka is closely related to changes in sediment provenance and paleoenvironment. Sea level rise and the strength of the Kuroshio Current control the dispersal and deposition of clays on the East China Sea shelf and in the Okinawa Trough, and thus, determine the clay mineral compositions in the core sediments. During the late last glacial period (28.0-14.0 ka), the paleo-Changjiang River... |
| Tipo: Text |
Palavras-chave: Clay mineral; Sediment; Provenance; East China Sea; Okinawa Trough. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00002/11367/7977.pdf |
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| Gobert, S; Kyramarios, M; Lepoint, G; Pergent-martini, C; Bouquegneau, Jm. |
| The biometric parameters (shoot density, length and width of leaves, leaf and epiphyte biomasses, leaf surface) of the P. oceanica meadow present a significant spatial variability at the mesoscale level (100m(2)). All the parameters studied, excepting the number of leaves, decrease according to the depth. The horizontal spatial variations (centrifuge and centripetal distributions) reach a maximum in the shallower areas. The analysis of the microstructures (m(2)) of the meadow has not allowed a relationship to be established between the spatial variations of the biometric parameters and the environmental factors in the sediment (pH, water and organic matter content, red-ox potential, nutrient content). The heterogeneity of the meadow in the Revellata Bay... |
| Tipo: Text |
Palavras-chave: Posidonia oceanica; Distribution spatiale; Biomasse; Sédiment; Phanérogame; Méditerranée; Posidonia oceanica; Spatial distribution; Biomass; Sediment; Seagrass; Mediterranean Sea. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00322/43277/43009.pdf |
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| Burgeot, Thierry; Quirion, Sophie; Quiniou, Francoise; Knoery, Joel; Soletchnik, Patrick; Gagnaire, Beatrice; Renault, Tristan; Osada, M.; Geret, F.; Communal, P. Y.; Jadas-hecart, A.; Gagne, F.. |
| In the Atlantic French coast, significant mortalities were observed in oyster communities during gametogenesis. These deaths possibly result from the cumulative effects of various stressors such as seasonal temperature variations, pesticide application and the release of contaminants from the resuspension of sediments. A field survey, based on aquaculture conditions at 15 and 70 cm from the sediment bed with genetically-resistant (R) and -sensitive (S) lines, showed a stress condition. Significant weight loss was observed during May 14th through June 10th for both R and S lines. On one hand, the levels of the egg yolk vitellin in females were decreased at May 14th for both R and S lines. On the other hand, a significant increase in vitellin production was... |
| Tipo: Text |
Palavras-chave: Mortalities; Herbicides; Sediment; Biomarkers; Gametogenesis; Crassostrea gigas; Pacific oysters. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3384.pdf |
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| Orvain, F; Sauriau, Pierre-guy; Bacher, Cedric; Prineau, Michel. |
| Laboratory experiments performed in a recirculating flume were designed to quantify the bioturbation influence of the mud snail Hydrobia ulvae, one of the most abundant deposit feeders on European intertidal mudflats. Variations in sediment moisture content that occur between bedforms in shore-normal, ridge and runnel systems of intertidal mudflats were added to the model definition. Sediment erosion thresholds, erosion rates and the microalgal pigment composition of resuspended material were quantified for different H. ulvae densities (0, 1000, 5000, 10 000 and 50 000 snails m(-2)) and applied bed shear stresses. Two different sediment moisture contents were tested. In the absence of macrofauna, recorded turbidities increased up to the maximum applied... |
| Tipo: Text |
Palavras-chave: Model; Flume; Chloropigments; Ridges and tunnels; Mudflat; Sediment; Hydrobia ulvae; Bioturbation; Resuspension. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-3774.pdf |
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| Feuillet-girard, Michelle; Heral, Maurice; Sornin, Jean-marc; Deslous-paoli, Jean-marc; Robert, Jean-michel; Mornet, Francoise; Razet, Daniel. |
| The respective influences of the sediment and of oyster (Crassostrea gigas) farming on the accumulation and the recycling of different forms of organic and inorganic nitrogen are described. Fluxes of dissolved inorganic and organic forms of nitrogen were studied between the water column, the water overlying the sediment and the pore waters, while for particulate forms the fluxes were studied between suspended material, the "biodeposits" (faeces and pseudofaeces of Crassostrea) and the sediment. The flux of inorganic nitrogen amounts to 10.5 106 g.m(-2). Yr(-1), while that of organic nitrogen is half this figure. The particulate flux is 15.106 g.m(-2).yr(-1). On the other hand, the phytoplanktonic nitrogen accounts for only 6% of the total particulate... |
| Tipo: Text |
Palavras-chave: Marenne Oleron; Sediment; Pore water; Interface; Crassostrea gigas; Nitrogen; Marennes Oléron; Sédiment; Eau interstitielle; Adsorption; Interface; Crassostrea gigas; Azote. |
| Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/1988/publication-2878.pdf |
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| Cheize, Marie; Planquette, H.f.; Fitzsimmons, J.n.; Pelleter, Ewan; Sherrell, R.m.; Lambert, Christophe; Bucciarelli, E.; Sarthou, G.; Le Goff, Marion; Liorzou, Celine; Chéron, Sandrine; Viollier, E.; Gayet, Nicolas. |
| A number of trace metals play essential roles in marine ecosystem structure and biological productivity. Until recently, it has been argued that phytoplankton access primarily dissolved iron, while particulate iron was considered a refractory material with little use biologically and limited interaction with the dissolved pool. In order to assess the transfer mechanisms between sediment-sourced particulate trace metals and the dissolved pool, we conducted a 14-month incubation that reacted resuspended sediments with natural seawater, both originating from the Kerguelen area (KEOPS cruises; Southern Ocean), in the dark, and at concentrations replicating natural conditions. Three types of sediments were investigated (named BioSi, BioSi + Ca, and Basalt),... |
| Tipo: Text |
Palavras-chave: Suspended particle dissolution; Sediment; Iron; Manganese; Biogenic silica; Southern Ocean; Kerguelen. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00460/57197/59166.pdf |
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| Giorgetti, Alessandra; Lipizer, Marina; Molina Jack, Maria Eugenia; Holdsworth, Neil; Jensen, Hans Mose; Buga, Luminita; Sarbu, George; Iona, Athanasia; Gatti, Julie; Larsen, Martin; Fyrberg, Lotta; Østrem, Ann Kristin; Schlitzer, Reiner. |
| Tipo: Text |
Palavras-chave: Nutrients; Oxygen; Acidity; Contaminants; Sediment; Biota; Aggregated datasets. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00663/77519/79314.pdf |
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| Tanty, Cyrielle; Valet, Jean-pierre; Carlut, Julie; Bassinot, Franck; Zaragosi, Sebastien. |
| Turbiditic events are mostly avoided in paleomagnetic studies and therefore their remanence and magnetic properties are poorly described. Turbidites are exempt of bioturbation and potentially provide pertinent information about depositional remanence. We studied four quaternary turbidites of different origins in marine sediment cores. Upward fining of both magnetic and sedimentary fractions indicates that coarser grains reached the bottom first. We observe a progressive shallowing of the magnetic inclinations between the upper and bottom layers of the turbidites that increases with the size of the events and obeys a simple linear scaling law. Measurements of magnetic anisotropy suggest that hydrodynamic conditions prevailing during deposition seem to be... |
| Tipo: Text |
Palavras-chave: Detrital remanence; Turbidite; Sediment; Rock magnetism; Magnetization. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00421/53226/54792.pdf |
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| Charmasson, S. |
| The low tidal range of the Mediterranean Sea and the high sediment load of the Rhone induce the formation of an important submarine delta. The Cs-137 inventory in sediment on a 480 km(2) area near the Rhone mouth reached 19.6 TBq in 1990. The spatial distribution of both sediment accumulation rates and (CS)-C-137 concentrations in this area confirm the existence of a spatially well-delimited zone, i.e. the prodelta, where both parameters are the highest. Thus, 40% of the total amount of Cs-137 stored in this 480 km(2) area was found within the prodelta (30 km(2)) in the close vicinity of the river mouth. This attests to the efficiency of the (CS)-C-137 trapping by the prodelta sediments. A study on the part the different (CS)-C-137 sources in the... |
| Tipo: Text |
Palavras-chave: Rhône; Méditerranée; Radioéléments; Sédiment; Inventaire; Rhone; Mediterranean Sea; Radionuclides; Sediment; Inventory. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00321/43266/42997.pdf |
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| Cossa, Daniel; Buscail, R.; Puig, P.; Chiffoleau, Jean-francois; Radakovitch, Olivier; Jeanty, G.; Heussner, S.. |
| Continental margins receive natural and anthropogenic trace elements (TEs) from direct atmospheric deposition of aerosols onto the sea surface and from advection of riverine suspended particles and/or resuspended sediments from the continental shelf/slope. When the margin is incised by submarine canyons, as for example in the Northwestern Mediterranean Sea, most of these particles are preferentially transferred via these topographic features towards their final repositories in the abyssal plain. The Gulf of Lions (GoL) shelf receives the largest particulate riverine input to the Western Mediterranean, with its associated chemical contaminants originating from the industrialized and urbanized Rhone Valley. Sediments samples (grabs, cores and moored traps)... |
| Tipo: Text |
Palavras-chave: Trace-element; Sediment; Canyon; Continental margin; Mediterranean. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00188/29971/28424.pdf |
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| Ouillon, S.; Douillet, Pascal; Lefebvre, J. P.; Le Gendre, Romain; Jouon, Aymeric; Bonneton, P.; Fernandez,; Chevillon, C.; Magand, O.; Lefevre, J.; Le Hir, Pierre; Laganier, R.; Dumas, Franck; Marchesiello, P.; Madani, A. Bel; Andrefouet, S.; Panche, J. Y.; Fichez, R.. |
| The south-west lagoon of New Caledonia is a wide semi-open coral reef lagoon bounded by an intertidal barrier reef and bisected by numerous deep inlets. This paper synthesizes findings from the 2000-2008 French National Program EC2CO-PNEC relative to the circulation and the transport of suspended particles in this lagoon. Numerical model development (hydrodynamic, fine suspended sediment transport, wind-wave, small-scale atmospheric circulation) allowed the determination of circulation patterns in the lagoon and the charting of residence time, the later of which has been recently used in a series of ecological studies. Topical studies based on field measurements permitted the parameterisation of wave set-up induced by the swell breaking on the reef barrier... |
| Tipo: Text |
Palavras-chave: Hydrodynamics; Suspended sediment; New Caledonia; Coral reef lagoon; Sediment; Turbidity; Resuspension. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00014/12526/9401.pdf |
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| Kempf, Marc; Cadour, Gwenael; Jeanneret, Hélène; Mear, Yan; Miramand, Pierre; Merceron, Michel. |
| This document is a result of an environmental impact study carried out between 1993 and 1995 on the site of a marine trout culture located in the Harbour of Cherbourg, France. It deals with the solid waste of the farm and concems deposition rate, sediment analysis and chemistry (fine fraction < 63 ~m, organic matter, carbon, nitrogen, copper and zinc), bottom living organisms and underwater video monitoring. The impact observed is very moderate and localised. This is mainly due to the strong d)'TIamics and flushing rate of the site. A seperate volume of the same study deals with dissolved waste and concems the water mass (volume 1 : water and pelagos). (Not controlled OCR) |
| Tipo: Text |
Palavras-chave: Rade de Cherbourg; Étude biosédimentaire; Impact; Salmoniculture marine; France; Cherbourg; Benthos; Sediment; Environmental impact; Trout; Marine fish farming. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/1997/rapport-3349.pdf |
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| Kervella, Youen. |
| Oyster farm structures represent artificial obstacles which can disturb tidal currents and wave propagation, and thus modify sediment transport patterns. Local deposition may result from these modifications, in proportions that may threaten the oyster farming. The impact of structures on hydrodynamics, waves and currents, is investigated at different spatial scales by means of in-situ measurements, experimental tests and numerical modeling. These different approaches show that in the near-field, tidal currents are modified in terms of intensity and direction but there is no significant impact on the waves. On the other hand, at the scale of the oyster farm, a significant reduction of the current velocities and a large wave height attenuation are recorded.... |
| Tipo: Text |
Palavras-chave: Tables à huîtres; Envasement; Courants; Vagues; Sédiments; Impact; Oyster tables; Silting up; Currents; Waves; Sediment; Impact. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00011/12262/9043.pdf |
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| Moukrim, A; Chiffoleau, Jean-francois; Cheggour, M; Burgeot, Thierry. |
| Monthly samples of sediment were collected from the Souss estuary, to determine the changes which have occurred in the concentrations of ten metals between 2001 when the low estuary was receiving the wastewaters from Agadir city and 2003 after stopping the sewage dumping. The annual contents of Cu, Fe, Zn (in 2001) and those of Cr, Cu, Fe, Mn, Ni, Pb, and Zn (in 2003) showed significant correlations with those of Al, indicating that fluctuations of their concentrations were only due to those of the aluminosilicate fraction of the clayey sediment. After normalization of these metallic concentrations in relation to those of Al, the contents of the different metals showed insignificant correlations between both years, except for Zn which significantly dropped... |
| Tipo: Text |
Palavras-chave: Souss estuary; Wastewater; Sediment; Metal contamination. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-5923.pdf |
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| Pascal, P.y.; Dupuy, C; Mallet, C; Richard, P; Niquil, N. |
| The fate of benthic bacterial biomass in benthic food webs is a topic of major importance but poorly described. This paper describes an alternative method for evaluation of bacterial grazing rate by meiofauna and macrofauna using bacteria pre-enriched with stable isotopes. Natural bacteria from the sediment of an intertidal mudflat were cultured in a liquid medium enriched with 15NH4Cl. Cultured bacteria contained 2.9% of 15N and were enriched sufficiently to be used as tracers during grazing experiments. Cultured bacteria presented a biovolume (0.21 μm3) and a percentage of actively respiring bacteria (10%) similar to those found in natural communities. The number of Operational Taxon Units found in cultures fluctuated between 56 and 75% of that... |
| Tipo: Text |
Palavras-chave: Tracer; Stable isotope; Sediment; Grazing; Bacteria. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4296.pdf |
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| Registros recuperados: 165 | |
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