The emerging role of climate in post-smolt growth of Atlantic salmon   总被引：1，自引：1，他引：1  

Friedland  Kevin D.; Chaput  Gerald; MacLean  Julian C. 《ICES Journal of Marine Science》2005,62(7):1338-1349

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The seasonal dynamics of six species of Dorvilleidae (Polychaeta) in the harbour of La Spezia (Italy)   总被引：1，自引：0，他引：1  

D. Prevedelli  G. Massamba N'Siala  & R. Simonini 《Marine Ecology》2005,26(3-4):286-293

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Preservation conditions and the use of sediment pigments as a tool for recent ecological reconstruction in four Northern European estuaries   总被引：4，自引：0，他引：4  

N. Reuss  D.J. Conley  T.S. Bianchi 《Marine Chemistry》2005,95(3-4):283-302

Down-core sediment pigment concentrations from four Northern European estuaries were measured using high-performance liquid chromatography (HPLC) to investigate phytoplankton community structure and preservation conditions over the last ca. 100 years where all sites have experienced different levels of eutrophication. Phytoplankton pigments have been shown to be useful biomarkers for phytoplankton community structure and abundance due to their taxonomic specificity. The pigment concentrations and sediment pigment inventory showed large variation between the four sites. Concentrations ranged from more than 6000 nmol/g OC to less than 100 nmol/g OC and the inventory integrated over the top 10 cm from more than 300 nmol/cm² to less than 30 nmol/cm² for total identified pigments. Good pigment preservation in Mariager Fjord (Denmark) reflected the almost permanently anoxic conditions. Pigments in Laajalahti (Finland) showed peak concentrations around the time of highest nitrogen loading events known from historical and modelled records over the past 100 years. In contrast, poor down-core preservation of pigments (especially carotenoids) was observed in the Ems-Dollard (The Netherlands) and Himmerfjärden (Sweden) estuaries. The Ems-Dollard site is an intertidal mudflat that experiences daily exposure to light and air, which enhances pigment degradation. In Himmerfjärden, resuspension is an important process affecting both the sedimentation rate and degradation properties. The different preservation conditions at the four sites were supported by the differences in two degradation indicators; the ratio of pheopigment-a to chlorophyll-a and total carotenoids to total pigments. Class-specific carotenoid pigments represented the dominant algal groups reported from each site, however, no distinct down-core changes in the pigment composition were observed at any of the four sites. This indicated that changes in plankton community structure on the group level have been limited over this time period or masked by low preservation of pigments.  相似文献   

Regimes and the history of the major fisheries off Canada's west coast     

R. J. Beamish  A. J. Benson  R. M. Sweeting  C. M. Neville 《Progress in Oceanography》2004,60(2-4):355

The major fisheries on the Pacific coast of Canada can be grouped into 12 species that have consistently represented about 80–90% of the total catch from the past to the present. A review of population dynamics of these species indicates that climate and the ocean environment have a major impact on their productivity. We review the history of Canada's Pacific coast fishery to show that trends in catch were similar to trends in the climate and ocean environment. Decadal scale patterns in climate and the ocean are termed regimes and we show that it is the regime scale of climate variability that most influences the long-term trends in the catches in these major fisheries. Ignoring the impacts of regime shifts on the abundance trends in the future could result in collapses of major fisheries. The difficulty of knowing when a regime shift will occur may be overcome as we discover more about the mechanisms that affect the decadal-scale trends in the rotational velocity of the solid earth which is measured as the length of day (LOD).  相似文献   

Jason-1: Assessment of the System Performances     

J. Perbos  P. Escudier  F. Parisot  G. Zaouche  P. Vincent  Y. Menard  F. Manon  G. Kunstmann  D. Royer  L. -L. Fu 《Marine Geodesy》2003,26(3):147-157

On 7 December 2001, Jason-1 was successfully launched by a Boeing Delta II rocket from the Vandenberg Air Force Base, California. The Jason-1 satellite will maintain the high accuracy altimeter service provided since 1992 by TOPEX/Poseidon (T/P), ensuring the continuity in observing and monitoring the Ocean Dynamics (intraseasonal to interannual changes, mean sea level, tides, etc.). Despite one-fourth the mass and power, the Jason-1 system has been designed to have basically the same performance as T/P, measuring sea surface topography at a centimetric level. This new CNES/NASA mission also provides near real-time data for sea state and ocean forecast. The first two months of the Jason-1 mission have been dedicated to the assessment of the overall system. The goals of this assessment phase were:

1. To assess the behavior of the spacecraft at the platform and payload levels (Jason-1 being the first program to call on the PROTEUS versatile multimission platform for Low and Medium Earth Orbit Missions developed in partnership between Alcatel Space and CNES);

2. To verify that platform performance requirements are met with respect to Jason-1 requirements;

3. To verify that payload instruments performance requirements evaluated at instrument level are met;

4. To assess the performance of the Jason-1 Ground System.

This article will display the main outputs of the assessment of the system. It will demonstrate that all the elements of the onboard and ground systems are within the specifications. Provision of data to the Jason-1 Science Working Team started at the end of March 2002. This is the goal of a six-month phase after closure of the initial assessment phase to derive the error budget of the system in terms of altimetry user products.  相似文献   

Seasonal variation of pteropods from the Western Arabian Sea sediment trap     

R. Mohan  K. Verma  L. P. Mergulhao  D. K. Sinha  S. Shanvas  M. V. S. Guptha 《Geo-Marine Letters》2006,26(5):265-273

Sediment trap samples collected from the Western Arabian Sea yielded a rich assemblage of intact and non-living (opaque white) pteropod tests from a water depth of 919 m during January to September 1993. Nine species of pteropods were recorded, all (except one) displaying distinct seasonality in abundance, suggesting their response to changing hydrographical conditions influenced by the summer/winter monsoon cycle. Pteropod fluxes increased during the April–May peak of the intermonsoon, and reached maximum levels in the late phase of the southwest summer monsoon, probably due to the shallowing of the mixed layer depth. This shallowing, coupled with enhanced nutrient availability, provides ideal conditions for pteropod growth, also reflected in corresponding fluctuations in the flux of the foraminifer Globigerina bulloides. Pteropod/planktic foraminifer ratios displayed marked seasonal variations, the values increasing during the warmer months of April and May when planktic foraminiferal fluxes declined. The variation in fluxes of calcium carbonate, organic carbon and biogenic opal show positive correlations with fluxes of pteropods and planktic foraminifers. Calcium carbonate was the main contributor to the total particulate flux, especially during the SW monsoon. In the study area, pteropod flux variations are similar to the other flux patterns, indicating that they, too could be used as a potential tool for palaeoclimatic reconstruction of the recent past.  相似文献   

Interspecies differences in heavy metal detoxication in oysters     

S.G. George  B.J. Pirie  J.M. Frazier  J.D. Thomson 《Marine environmental research》1984,14(1-4)

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Seasonal distribution and growth of larval herring (Clupea harengus L.) in the Georges Bank-Gulf of Maine area from 1962 to 1970     

Boyar  H. C.; Marak  R. R.; Perkins  F. E.; Clifford  R. A. 《ICES Journal of Marine Science》1973,35(1):36-51

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The Winter Distribution of Silicate in Southampton Water     

Banoub  M. W.; Burton  J. D. 《ICES Journal of Marine Science》1968,32(2):201-208

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The Shandong mud wedge and post-glacial sediment accumulation in the Yellow Sea   总被引：14，自引：0，他引：14  

J. P. Liu  J. D. Milliman  S. Gao 《Geo-Marine Letters》2002,21(4):253-254

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