Tilt angle and target strength: target tracking of Atlantic cod (Gadus morhua) during trawling     

McQuinn  Ian H; Winger  Paul D 《ICES Journal of Marine Science》2003,60(3):575-583

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Direct barite determination using SEM/EDS-ACC system: implication for constraining barium carriers and barite preservation in marine sediments     

E. Robin  C. Rabouille  G. Martinez  I. Lefevre  J. L. Reyss  P. van Beek  C. Jeandel 《Marine Chemistry》2003,82(3-4):289-306

Barite (BaSO₄) in marine sediments is considered as a proxy of surface ocean productivity and is widely used for paleo-productivity reconstructions. However, direct barite determination is not achieved by currently used methods, which rely on the measurement of total barium by inductively coupled plasma–mass spectrometry (ICP-MS) and instrumental neutron activation analysis (INAA) and correction from the allogenic Ba contribution. We report here on a technique that directly counts individual barite crystals using a scanning electron microscope (SEM) coupled to an energy dispersive spectrometer (EDS) equipped with an automated particle counting and classification (ACC) system. We show that barite–Ba concentrations can be deduced from the abundance, shape and size distributions of barite crystals with current precision and sensitivity as high as ±5 wt.% (2σ confidence limit) and 10 ppm, respectively. This technique, coupled with ICP-MS and INAA techniques for total Ba measurements, was applied to sediment samples from the tropical North Atlantic and the Central North Pacific oceans. Results show that: (1) barite and detrital aluminosilicates are the two main carriers of Ba in the investigated sediments; (2) calculated Ba/Al ratios range from 0.005 to 0.008 with an average value around 0.0066, in close agreement with previously reported values; (3) barite might not be the major source for released barium out of sediments and we suggest instead adsorbed barium as a potential source.  相似文献   

The response of Calanus finmarchicus populations to climate variability in the Northwest Atlantic: basin-scale forcing associated with the North Atlantic Oscillation   总被引：2，自引：0，他引：2  

Greene  C. H.; Pershing  A. J. 《ICES Journal of Marine Science》2000,57(6):1536-1544

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Henslow's swimming crab (Polybius henslowii) as an important food for yellow-legged gulls (Larus cachinnans) in NW Spain     

Munilla  Ignacio 《ICES Journal of Marine Science》1997,54(4):631-634

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The occurrence and spawning of cultured Atlantic salmon (Salmo salar) in a Canadian river     

Carr  J. W.; Anderson  J. M.; Whoriskey  F. G.; Dilworth  T. 《ICES Journal of Marine Science》1997,54(6):1064-1073

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Estimation of marine exploitation rates on Atlantic salmon (Salmo salar L.) stocks in Newfoundland, Canada   总被引：1，自引：0，他引：1  

Dempson  J. B.; Schwarz  C. J.; Reddin  D. G.; O'Connell  M. F.; Mullins  C. C.; Bourgeois  C. E. 《ICES Journal of Marine Science》2001,58(1):331-341

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Microhabitat type determines the composition of nematode communities associated with sediment-clogged cold-water coral framework in the Porcupine Seabight (NE Atlantic)   总被引：1，自引：0，他引：1  

M. Raes  A. Vanreusel 《Deep Sea Research Part I: Oceanographic Research Papers》2006,53(12):1880-1894

The nematofauna associated with a cold-water coral degradation zone in the Porcupine Seabight (NE Atlantic) was investigated. This is the first comprehensive study of nematodes associated with cold-water corals. This research mainly aimed to investigate the influence of microhabitat type on nematode community structure. Three distinct microhabitats for nematodes were distinguished: dead coral fragments, glass sponge skeletons and the underlying sediment. The nematode assemblages associated with these three microhabitats were significantly different from each other. Coral and sponge substrata lie relatively unprotected on the seafloor and are consequently more subjected to strong currents than the underlying sediment. As a result, both large biogenic substrata were characterized by higher abundances of taxa that are less vulnerable and more adapted to physical disturbance, whereas the underlying sediment yielded more slender, sediment-dwelling taxa. Typically epifaunal taxa, such as Epsilonematidae and Draconematidae, were especially abundant on dead coral fragments, where they are thought to feed on the microbial biofilm which covers the coral surface. Several epifaunal genera showed significant preferences for this microhabitat, and Epsilonema (Epsilonematidae) was dominant here. Sponge skeletons are thought to act as efficient sediment traps, resulting in a lower abundance of epifaunal taxa compared to coral fragments. The underlying sediment was dominated by taxa typical for slope sediments. The considerable degree of overlap between the communities of each microhabitat is attributed to sediment infill between the coral branches and sponge spicules. It is assumed that the nematofauna associated with large biogenic substrata is composed of a typical sediment-dwelling background community, supplemented with taxa adapted to an epifaunal life strategy. The extent to which these taxa contribute to the community depends on the type of the substratum. Selective deposit feeders were dominant on sponge skeletons and in the underlying sediment, whereas coral fragments were dominated by epistratum feeders. The presence of a microbial biofilm on the coral fragments is proposed as an explanation for the significant preference of epistratum feeders for this microhabitat. Densities in the underlying sediment were low in comparison with other studies, but biodiversity was higher here than on the coral and sponge fragments, a difference which is attributed to lower disturbance. Nevertheless, the large biogenic substrata provide a microhabitat for rare, epifaunal taxa, and fragments of both substrata within the sediment increase habitat complexity and hence biodiversity.  相似文献   

Zooplankton trends: US north-east shelf ecosystem and adjacent regions differ from north-east Atlantic and North Sea     

Jossi  J. W.; Goulet  J. R.  Jr 《ICES Journal of Marine Science》1993,50(3):303-313

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Monitoring the incidence of escaped farmed Atlantic salmon, Salmo salar L., in rivers and fisheries of the United Kingdom and Ireland: current progress and recommendations for future programmes   总被引：1，自引：0，他引：1  

Walker  Alan M.; Beveridge  Malcolm C.M.; Crozier  Walter; O Maoileidigh  Niall; Milner  Nigel 《ICES Journal of Marine Science》2006,63(7):1201-1210

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ENSO as a natural experiment to understand environmental control of meiofaunal community structure   总被引：2，自引：0，他引：2  

Javier Sellanes  & Carlos Neira 《Marine Ecology》2006,27(1):31-43

The sediments of the Bay of Concepción and the adjacent shelf underlie one of the most productive upwelling areas in the SE Pacific margin. Reports on factors controlling meiofaunal community structure in these kinds of organic‐rich and oxygen‐deficient habitats are scarce in the literature. In this study, five sites along a transect from the mid‐Bay of Concepción (27 m) to the outer shelf (120 m) were studied on fives dates (May, August, November 1997, and March and May 1998) in order to assess the dynamic relationships between sedimentary organic matter and metazoan meiofauna. The sampling period coincided with the 1997–1998 El Niño event. Sediment parameters investigated were the redox potential discontinuity depth, photosynthetic pigment concentrations (chlorophyll a and phaeopigments), organic carbon, nitrogen, total lipids, carbohydrates, and proteins. In general, lowest values of meiofauna abundance and biomass were found within the naturally eutrophic Bay of Concepción and towards the shelf break, while maximum values occurred at intermediate depths. During the whole period, the meiofaunal abundance was negatively correlated with the concentration of most of the biochemical components of organic matter, as well as with the sediment phaeopigment content. However, positive correlations were found with chlorophyll a derived indices and with bottom‐water oxygen content. Most of the sediment parameters displayed a seasonal cycle, but towards the beginning of 1998, an effect of the 1997–1998 El Niño was evident. Typical austral‐summer (i.e. oxygen‐deficient) conditions did not develop, and sedimentary parameters reflected a decreased input of phytodetritus. Along the transect, the magnitude of this effect on meiofauna varied among sites. An overall positive response, in terms of meiofaunal abundance was observed, probably due to the amelioration of low oxygen conditions in the sediment.  相似文献