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| Registros recuperados: 27 | |
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| Billen, G.; Joiris, C.R.; Wijnant, J.; Gillain, G.. |
| Concentrations and utilization rates of alanine, aspartate, lysine, glucose, glycollic, acetic and lactic acids have been determined on 6 occasions at least, during a full seasonal cycle in the water column of 3 stations (Scheldt estuary, coastal North Sea and English Channel) with greatly differing biological characteristics. No significant differences in substrate concentration could be detected between the 3 stations, although the rate of utilization of all substrates differed greatly, decreasing in the order estuarine > coastal > open sea environment. This apparent paradox is explained by aid of a simple model showing that the steady state concentration of a particular substrate is independent of its rate of production (and thus of consumption)... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Organic compounds ANE; Belgium; Belgian Coast ANE; English Channel Belgium; Zeeschelde. |
| Ano: 1980 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=6912 |
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| Joiris, C.R.; Billen, G.; Lancelot, MH.; Daro, M.H.; Mommaerts, J.-P.; Bertels, A.; Bossicart, M.; Nijs, J.; Hecq, J.H.. |
| The various biological compartments of the Belgian coastal zone of the North Sea were studied since 1971. The synthesis of available data on carbon cycling includes phytoplankton biomass and activities (particulate and dissolved primary production, respiration) , zooplankton biomass and activities (grazing, respiration) and planktonic and benthic microbial heterotrophic activities. These various carbon flux estimates allow the development of an overall budget of carbon cycling. This budget shows the importance of microbial (planktonic and benthic) heterotrophs versus zooplankton in the utilization of primary production. Comparison with literature data suggests that this could be a general feature of coastal, as opposed to open sea ecosystems. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1982 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=6908 |
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| Joiris, C.R.. |
| During the ARK V/2 expedition of RV <i>Polarstern</i> in the Norwegian and Greenland seas in June 1988, 380 half hour counts for marine vertebrates (seabirds, pinnipeds and cetaceans) were carried out. Results are presented as total numbers encountered and then converted into density and food intake. Mean food intake was 2.2 kg fresh weight per km<sup>2</sup> per day for seabirds, with a higher value in Atlantic water (2.5) lower values in polar water and the pack ice (1.7 and 1.9), and an intermediate value at the ice edge. The main species were the alcids (1.5, primarily Little Auk, <i>Alle alle</i> and Brünnich's Guillemot, <i>Urea Iomvia</i>), the Fulmar, <i>Fulmarus glacialis</i> (0.5), and... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1992 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=6886 |
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| Antoine, N.; Jansegers, I.; Holsbeek, L.; Joiris, C.R.; Bouquegneau, J.-M.. |
| In the North Sea, the contamination level of Cd in porpoises, Zn and Cu in seabirds and Hg in both appear to be very high. The other studied metals (Cr, Ti, Fe, Pb) concentrations are comparable to literature. Seabirds and porpoises are located at top of the food chains, however their use as bioindicators of the contamination level of the ecosystem they are feeding on remains debatable. Actually many differences appear in both the contamination level and the storage and detoxification mechanisms from a species to another. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aves [Birds]; Phocoenidae [porpoises]. |
| Ano: 1992 |
URL: http://www.vliz.be/imisdocs/publications/237547.pdf |
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| Joiris, C.R.; Kampp, K.; Tahon, J.; Møbjerg Kristensen, R.. |
| The distribution at sea of seabirds was studied in the North-East Water (NEW) polynya, Greenland, during transect counts in the summers of 1991, 1992 and 1993 on board the ice-breaking RVs Polarstern and Polar Sea. Data collected within the polynya ‘box’ (78–82°N; 5–18°W) concern observations of 8000 birds counted during 1350 half-hour counts. Distribution is presented as density (N/km2) and calculated daily food intake. Five bird species were selected for discussion, representing more than 95% of the total numbers encountered: Fulmar (Fulmarus glacialis), Ivory Gull (Pagophila eburnea), Kittiwake (Rissa tridactyla), Glaucous Gull (Larus hyperboreus) and Ross's Gull (Rhodostethia rosea). For these species, densities are comparable in the NE Greenland... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1997 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=6859 |
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| Joiris, C.R.; Tapia, G.; Holsbeek, L.. |
| Beached seabirds, mainly common guillemots Uria aalge, were collected on the Belgian coast during winter from 1990 to 1995. Concentrations of total and organic mercury, and of organochlorines (PCBs and pesticides) were determined in muscle, liver and kidney. They were high compared to summer data (up to one order of magnitude), and increased during winter. This increase is not due to changes of total body weight nor polar lipid content, and thus reflects an actual increase of the seabirds' contamination while wintering in the southern North Sea. The observed annual cycle can be understood by assuming differences in prey contamination: higher during winter in the southern North Sea ecosystem than during summer in the Atlantic water ecosystem. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1997 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=6846 |
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| Registros recuperados: 27 | |
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