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| Registros recuperados: 1.500 | |
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| Soetaert, K.; Herman, P.M.J.; Middelburg, J.J.; Heip, C.H.R.; deStigter, H.S.; van Weering, T.C.E.; Epping, E.; Helder, W.. |
| The influence of sediment mixing on activity versus depth profiles of the radionuclide <sup>210</sup>Pb in the upper 20 cm of the sediments has been investigated along a depth transect (208 m-4500 m, 17 stations) in the OMEX study area (Goban Spur, NE Atlantic Ocean). A hierarchical family of bioturbation/nonlocal exchange models was derived. Each member of the hierarchy includes all processes of the previous model, and adds a one- or two-parameter process. The significance of the additional parameters is tested using a one-tailed <i>F</i>-test. It was found that (1) in five cases there is a significant improvement when direct injection of part of the flux into deeper sediment layers (nonlocal exchange) is added to the diffusive... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chemical kinetics Continental margins Diffusion Lead 210 Modelling Sediment mixing ANE; Goban Spur. |
| Ano: 1996 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=8450 |
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| Soetaert, K.; Heip, C.H.R.. |
| The nematode assemblages along a deep-sea transect in the Mediterranean are composed of individuals that are as small as those found in other areas at much greater depth. This may be related to the low surface primary production since chloroplastic pigment equivalent (CPE) values in the sediments are low as well. A significant decrease of both nematode size and sedimentary CPE values with increasing water depth was found. At all water depths average nematode length increases with depth in the sediment (0-2 cm) due to the decreasing abundance of smaller nematodes. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1989 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=8470 |
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| Dehairs, F.A.; Kopczynska, E.; Nielsen, C.; Lancelot, C.; Bakker, D.; Koeve, W.; Goeyens, L.. |
| Observations are presented for stable carbon isotope abundance (δ<sup>13</sup>C) and organic carbon and nitrogen content of suspended organic matter from the Southern Ocean (Circumpolar Current and Polar Front) during spring and early summer. The Polar Front Zone was characterized by elevated plankton biomasses and phytoplankton activity, which also increased significantly over the one-month investigation period. From the beginning of the phytoplankton bloom δ<sup>13</sup>C values of suspended organic matter in the Polar Front were high, exceeding values predicted from the relationship with CO<sub>2(aq)</sub> concentration observed in other areas of the Southern Ocean. Later in the season... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1997 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=10202 |
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| Van Sprang, P.; Léger, P.; Sorgeloos, P.. |
| A new test system is described for the evaluation of toxic levels of liposoluble products in the aquatic food chain using <i>Artemia</i> and <i>Mysidopsis bahia</i> (M.) as experimental animals. For this, freshly released juveniles (<24h old) of <i>M. bahia</i> are transferred to the experimental bioassay test system, cultured under standard conditions and fed 24h old purposely contaminated <i>Artemia</i> nauplii. After 11 days, data on survival, reproductive characteristics, individual length and dry weight are recorded and treated statistically. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1991 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2910 |
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| Triantaphyllidis, G.; Criel, G.R.J.; Abatzopoulos, T.J.; Sorgeloos, P.. |
| A detailed morphological and allometrical study was performed with adult males and females of eleven bisexual populations of brine shrimp <i>Artemia</i> . Multivariate procedures, discriminant and cluster analysis, allowed to separate and group together populations which exhibit great genetic similarities. The eleven populations studied form four distinct groups: the <i>A. franciscana</i> group, the <i>A. tunisiana</i> group, the <i>A. urminiana</i> group and a broader group which includes Eastern Old World populations. Scanning electron microscopy revealed differences in the male genital organs of an <i>A. tunisiana</i> population by lacking a medial protuberance in the base of the penes while... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Artemia. |
| Ano: 1997 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2973 |
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| Van Ginneken, L.; Blust, R.. |
| A combined gamma scintillation/liquid scintillation technique for the sequential determination of two radioactive tracers is described. The method was developed using a combined gamma/ß-emitter (<sup>57</sup>Co) and a pure ß-emitter (<sup>45</sup>Ca). First, the <sup>57</sup>Co radioactivity was determined by counting the samples in a gamma scintillation analyzer in the energy region 80-165 keV. Next, the samples were counted in a liquid scintillation analyzer. Only one energy region was used to count both isotopes to maximize the counting efficiencies. From the difference between quenched and unquenched ß-spectra, the counting region was set from 0 to 256 keV. The counting efficiency was related to a quench-indicating... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1995 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2650 |
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| Clegg, J.S.; Drinkwater, L.E.; Sorgeloos, P.. |
| The brine shrimp <i><i>Artemia</i> franciscana</i> is widely used in aquaculture and basic research in areas ranging from molecular biology to evolution and ecology. A key of its life history involves the production of encysted embryos whose development is halted (enters diapause) at the gastrula stage. These shelled embryos are released into the aqueous environment where diapause continues until terminated by suitable conditions that produce an "activated embryo", which then can resume development when conditions permit. Very little is known about the metabolism of diapause embryos, in contrast to activated embryos, which have been studied extensively. We have examined selected features of metabolism in diapause embryos produced in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diapause; Embryos; Metabolism; Artemia franciscana. |
| Ano: 1996 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=2924 |
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| Moens, T.; Vincx, M.. |
| The present study investigates the influence of salinity and temperature on the life history of two estuarine bacterivorous nematode species, <i>Pellioditis marina</i> and <i>Diplolaimelloides meyli</i>, isolated from the mesohaline zone of the Westerschelde Estuary, SW Netherlands. Gravid females and adult males were inoculated in petri dishes containing agar layers of nine (for <i>P. marina</i>) or five (for <i>D. meyli</i>) different salinities, from almost freshwater to higher than marine, and incubated at a temperature of 20°C, to study the impact of salinity; agar layers with a salinity of 20‰, incubated under each of six different temperatures from 5 to 30°C, served to study the effect of temperature.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nematoda [Nematodes]. |
| Ano: 2000 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=7421 |
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| Heip, C.H.R.. |
| The assessment of the impact of pollution on the marine environment depends on the possibility of prediction either by comparison or more ideally by the analysis of time series which are long enough. Obtaining data for the construction of these time series should be one of the principal goals of monitoring. Parameters which are measured should have a low variability in time and in space or low frequency. The analysis of meiobenthic communities in the North Sea and the adjacent estuaries shows that harpacticoid copepods are especially suitable as the number and the nature of the species are stable and density, biomass, and diversity are characterized by the absence of variance in the high frequencies. Nematodes, though overwhelmingly abundant, are more... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Environmental assessment; Meiobenthos; Quality control. |
| Ano: 1980 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3682 |
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| Podamo, J.. |
| The food chain of plankton at the Sluice-Dock is reduced to the simple system "producers-primary consumers". The role of zooplankton is most important only for a short time, namely in May, when it restricts the development of phytoplankton by its grazing activity, and becomes the main source of nutrients due to its excretory activity. After the disappearance of most of the zooplankton biomasses, caused by a mortality that is not due to predation, the phytoplankton can again develop. At other times of the year, the zooplankton activities such as production, grazing, excretion, and respiration only represent 1% of the total plankton activity. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: ANE; Belgium; Oostende Harbour; Sluice Dock. |
| Ano: 1976 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3537 |
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| Joiris, C.. |
| Between 23 June and 1 August 1974, I sailed with the yacht "Atalante" from Nieuport (Belgium), along the east coast of Great Britain, to Thorshavn (Faeroes), several points along the east and north-east coasts of Iceland, then to Angmagssalik in Greenland and back, via Reykjavik, the Vestmann Islands (Iceland) and Edinburgh (Scotland) to Nieuport. Our speed was about 9 knots (17km/h). Birds were recorded during standard one-hour observation periods (in fractions of a quarter of an hour), from a point situated at the rear of the yacht, about 1.5 m above sea-level. They could be seen in all directions but the visibility was rather poor forwards. Although engaged in other tasks outside of these standard procedures, I was sometimes able to record the number of... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1976 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3553 |
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| Richard, A.; Van den Branden, C.; Decleir, W.. |
| The reproductive system of female cephalopods includes a glandular system (oviduct glands and nidamental glands), which develops considerably during sexual maturation and which plays an important part in the formation of the different egg membranes. It is generally uncoloured. An exception are the nidamental glands in <i>Nautilus pompilius</i> which are composed of opaque yellowish or yellowish-green tissue (Ref. 1). Moreover all Sepioidea and Myopsida and <i>Ctenopteryx</i>, a species belonging to the Oegopsida (Ref.2) possess accessory nidamental glands. The most striking property of these glands is their intense coloration varying from yellow to orange and red. This paper is a comparative study of the accessory nidamental glands... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Endocrine systems; Glands; Cephalopoda. |
| Ano: 1979 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3609 |
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| Bastin, A.; Malherbe, B.; Caillot, A.. |
| An extensive program of tracer experiments was carried out for calculating sediment transport in the vicinity of the Port of Zeebrugge where extension operations are in progress. Offshore radioactive bottom tracers were used for studying the sand transport along the beaches where erosion problems exist. On the beach itself fluorescent tracers were used. For the evaluation of the silting-up rate of the access channels to the harbour a series of radioactive bottom and suspension tracers were tracked <i>in situ</i>. For determining the efficiency of future dumping grounds a combination of bottom tracers and suspension tracers was used. In total, 18 experiments with radioactive tracers were carried out and 9 with fluorescent ones. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: ANE; Belgium; Belgian Coast. |
| Ano: 1983 |
URL: http://www.vliz.be/imisdocs/publications/128948.pdf |
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| Registros recuperados: 1.500 | |
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