Friday, September 19, 2014

 

 



Soy un nuevo usuario

Olvidé mi contraseña

Entrada usuarios

Lógica Matemáticas Astronomía y Astrofísica Física Química Ciencias de la Vida
Ciencias de la Tierra y Espacio Ciencias Agrarias Ciencias Médicas Ciencias Tecnológicas Antropología Demografía
Ciencias Económicas Geografía Historia Ciencias Jurídicas y Derecho Lingüística Pedagogía
Ciencia Política Psicología Artes y Letras Sociología Ética Filosofía
 

rss_1.0 Recursos de colección

ArchiMer, Institutional Archive of Ifremer (French Research Institute for Exploitation of the Sea) (9,141 recursos)
Archimer, is the institutional repository of Ifremer (French Research Institute for Exploitation of the Sea). It provides freely available scientific or technical documents online (publications, theses, conference proceedings, etc) in all fields related to oceans (oceanography, aquaculture, fisheries, etc). The site is available in French and English.

ec_fundedresources

Mostrando recursos 1 - 20 de 90

1. Marine Litter Distribution and Density in European Seas, from the Shelves to Deep Basins - Pham, Christopher K.; Ramirez-llodra, Eva; Alt, Claudia H. S.; Amaro, Teresa; Bergmann, Melanie; Canals, Miquel; Company, Joan B.; Davies, Jaime; Duineveld, Gerard; Galgani, Francois; Howell, Kerry; Huvenne, Veerle A. I.; Isidro, Eduardo; Jones, Daniel O. B.; Lastras, Galderic; Morato, Telmo; Gomes-pereira, Jose Nuno; Purser, Autun; Stewart, Heather; Tojeira, Ines; Tubau, Xavier; Van Rooij, David; Tyler, Paul A.
Anthropogenic litter is present in all marine habitats, from beaches to the most remote points in the oceans. On the seafloor, marine litter, particularly plastic, can accumulate in high densities with deleterious consequences for its inhabitants. Yet, because of the high cost involved with sampling the seafloor, no large-scale assessment of distribution patterns was available to date. Here, we present data on litter distribution and density collected during 588 video and trawl surveys across 32 sites in European waters. We found litter to be present in the deepest areas and at locations as remote from land as the Charlie-Gibbs Fracture...

2. Global habitat preferences of commercially valuable tuna - Arrizabalaga, Haritz; Dufour, Florence; Kell, Laurence; Merino, Gorka; Ibaibarriaga, Leire; Chust, Guillem; Irigoien, Xabier; Santiago, Josu; Murua, Hilario; Fraile, Igaratza; Chifflet, Marina; Goikoetxea, Nerea; Sagarminaga, Yolanda; Aumont, Olivier; Bopp, Laurent; Herrera, Miguel; Fromentin, Jean-marc; Bonhomeau, Sylvain
In spite of its pivotal role in future implementations of the Ecosystem Approach to Fisheries Management, current knowledge about tuna habitat preferences remains fragmented and heterogeneous, because it relies mainly on regional or local studies that have used a variety of approaches making them difficult to combine. Therefore in this study we analyse data from six tuna species in the Pacific, Atlantic and Indian Oceans in order to provide a global, comparative perspective of habitat preferences. These data are longline catch per unit effort from 1958 to2007 for albacore, Atlantic bluefin, southern bluefin, bigeye, yellowfin and skipjack tunas. Both quotient...

3. The effect of discards and survival rate on the Maximum Sustainable Yield estimation based on landings or catches maximisation: Application to the nephrops fishery in the Bay of Biscay - Guillen, Jordi; Macher, Claire; Merzéréaud, Mathieu; Fifas, Spyros; Guyader, Olivier
MSY objectives are being adopted as major fisheries management targets worldwide. However, in fisheries where discards account for an important share of the catches, the yield, effort, and biomass at MSY can be significantly different when accounting or not for discards and thus when, basing the yield estimations on landings or catches. Also whether accounting for a certain survival rate, of discards can lead to different MSY targets estimates. Hence, both decisions have important, implications on catch and effort reduction recommendations, and consequently on the quota, calculations for fisheries managed by quotas. Results from the Bay of Biscay nephrops fishery...

4. A framework for evaluating management plans comprehensively - Trenkel, Verena; Rochet, Marie-joelle; Rice, Jake C
We present a framework for evaluating fisheries management plans comprehensively, both rebuilding plans and others. The framework includes a first rapid appraisal of the likelihood that the plan will result in management meeting its objectives, and guides subsequent quantitative analyses of potential weaknesses in the proposed plan. The framework includes four steps: (i) evaluating if a set of management objectives, if achieved, would result in a sustainable fishery, (ii) using qualitative analysis of a bio-economic model to evaluate whether the set of stock management tactics might be capable of achieving the specified fisheries objectives, (iii) using empirical criteria derived from...

5. Observations of large infragravity wave runup at Banneg Island, France - Sheremet, Alex; Staples, Tracy; Ardhuin, Fabrice; Suanez, Serge; Fichaut, Bernard
On Banneg Island, France, very high water-level events (6.5 m above the astronomical tide) have been observed on the western cliff, exposed to large swells from the North Atlantic. The analysis of hydrodynamic measurements collected during the storm of 10 February 2009 shows unusually high (over 2 m) infragravity wave runup events. By comparing runup observations to measurements in approximately 7 m of water and numerical simulations with a simplified nonlinear model, two distinct infragravity bands may be identified: an 80 s infragravity wave, produced by nonlinear shoaling of the storm swell; and a 300 s wave, trapped on the intertidal...

6. Dual transcriptomics of virus-host interactions: comparing two Pacific oyster families presenting contrasted susceptibility to ostreid herpesvirus 1 - Segarra, Amelie; Mauduit, Florian; Faury, Nicole; Trancart, Suzanne; Degremont, Lionel; Tourbiez, Delphine; Haffner, Philippe; Barbosa-solomieu, Valerie; Pepin, Jean-francois; Travers, Marie-agnes; Renault, Tristan
Background: Massive mortality outbreaks affecting Pacific oyster (Crassostrea gigas) spat in various countries have been associated with the detection of a herpesvirus called ostreid herpesvirus type 1 (OsHV-1). However, few studies have been performed to understand and follow viral gene expression, as it has been done in vertebrate herpesviruses. In this work, experimental infection trials of C. gigas spat with OsHV-1 were conducted in order to test the susceptibility of several bi-parental oyster families to this virus and to analyze host-pathogen interactions using in vivo transcriptomic approaches. Results: The divergent response of these oyster families in terms of mortality confirmed that...

7. Large-scale distribution of three deep-water squaloid sharks: Integrating data on sex, maturity and environment - Moura, Teresa; Jones, Emma; Clarke, Maurice W.; Cotton, Charles F.; Crozier, Paul; Daley, Ross K.; Diez, Guzman; Dobby, Helen; Dyb, Jan E.; Fossen, Inge; Irvine, Sarah B.; Jakobsdottir, Klara; Lopez-abellan, Luis J.; Lorance, Pascal; Pascual-alayon, Pedro; Severino, Ricardo B.; Figueiredo, Ivone
Deep-water sharks exhibit species-specific reproductive strategies, which include segregation by sex, size and reproductive stage. However, due to the wide spatial distribution of most species, available information, usually collected at a regional scale, is usually not adequate to infer species reproductive spatial dynamics. This study draws together information on the distribution of reproductive stages of three species of squaliform sharks: Portuguese dogfish Centroscymnus coelolepis (Somniosidae), leafscale gulper shark Centrophorus squamosus (Centrophoridae) and birdbeak dogfish Deania calcea (Centrophoridae), gathering data from several geographical areas from the Atlantic, Indian and Pacific Oceans. For each species we analysed the sex ratio and the...

8. Effects of waves on coastal water dispersion in a small estuarine bay - Delpey, Matthias; Ardhuin, Fabrice; Otheguy, P.; Jouon, Aymeric
A three-dimensional wave-current model is used to investigate wave-induced circulations in a small estuarine bay and its impact on freshwater exchanges with the inner shelf, related to stratified river plume dispersion. Modeled salinity fields exhibit a lower salinity surface layer due to river outflows, with typical depth of 1 m inside the bay. The asymmetric wave forcing on the bay circulation, related to the local bathymetry, significantly impacts the river plumes. It is found that the transport initiated in the surf zone by the longshore current can oppose and thus reduce the primary outflow of freshwater through the bay inlets....

9. A new compilation of stomach content data for commercially-important pelagic fish species in the Northeast Atlantic - Pinnegar, J. K.; Goñi, N.; Trenkel, Verena; Arrizabalaga, H.; Melle, W.; Keating, J.; Óskarsson, G.
There is increasing demand for information on predator-prey interactions in the ocean as a result of legislative commitments aimed at achieving sustainable exploitation. However, comprehensive datasets are lacking for many fish species and this has hampered development of multispecies fisheries models and the formulation of effective food-web indicators. This work describes a new compilation of stomach content data for five pelagic fish species (herring, blue whiting, mackerel, albacore and bluefin tuna) sampled across the northeast Atlantic and submitted to the PANGAEA open-access data portal (www.pangaea.de). We provide detailed descriptions of sample origin and of the corresponding database structures. We describe...

10. The aggregation of tuna around floating objects: What could be the underlying social mechanisms? - Robert, Marianne; Dagorn, Laurent; Deneubourg, Jean Louis
Several empirical and theoretical studies have shown how the exploitation of food sources, the choice of resting sites or other types of collective decision-making in heterogeneous environments are facilitated and modulated by social interactions between conspecifics. It is well known that many pelagic fishes live in schools and that this form of gregarious behavior provides advantages in terms of food intake and predator avoidance efficiency. However, the influence of social behavior in the formation of aggregations by tuna under floating objects (FOBs) is poorly understood. In this work, we investigated the collective patterns generated by different theoretical models, which either...

11. Oceans and Human Health: A Rising Tide of Challenges and Opportunities for Europe - Fleming, L.e.; Mcdonough, N.; Austen, M.; Mee, L.; Moore, Michael; Hess, Philipp; Depledge, M.h.; White, M.; Philippart, Katja; Bradbrook, P.; Smalley, A.
The European Marine Board recently published a position paper on linking oceans and human health as a strategic research priority for Europe. With this position paper as a reference, the March 2014 Cornwall Oceans and Human Health Workshop brought together key scientists, policy makers, funders, business, and non governmental organisations from Europe and the US to review the recent interdisciplinary and cutting edge research in oceans and human health specifically the growing evidence of the impacts of oceans and seas on human health and wellbeing (and the effects of humans on the oceans). These impacts are a complex mixture of...

12. Variability of the transport of anthropogenic CO2 at the Greenland-Portugal OVIDE section: controlling mechanisms - Zunino Rodriguez, Patricia; Garcia-ibanez, Maria Isabel; Lherminier, Pascale; Mercier, Herle; Rios, A. F.; Perez, Ff
The interannual to decadal variability in the transport of anthropogenic CO2 (Cant) across the subpolar North Atlantic (SPNA) is investigated, using summer data of the FOUREX and OVIDE high-resolution transoceanic sections, from Greenland to Portugal, occupied six times from 1997 to 2010. The transport of Cant across this section, T-cant hereafter, is northward, with a mean value of 254 +/- 29 kmol s(-)1 over the 1997-2010 period. We find that T-cant undergoes interannual variability, masking any trend different from 0 for this period. In order to understand the mechanisms controlling the variability of T-cant across the SPNA, we propose a...

13. A Microarray-Based Analysis of Gametogenesis in Two Portuguese Populations of the European Clam Ruditapes decussatus - Sousa, Joana; Milan, Massimo; Bargelloni, Luca; Pauletto, Marianna; Matias, Domitilia; Joaquim, Sandra; Matias, Ana Margarete; Quillien, Virgile; Leitao, Alexandra; Huvet, Arnaud
The European clam, Ruditapes decussatus is a species with a high commercial importance in Portugal and other Southern European countries. Its production is almost exclusively based on natural recruitment, which is subject to high annual fluctuations. Increased knowledge of the natural reproductive cycle of R. decussatus and its molecular mechanisms would be particularly important in providing new highly valuable genomic information for better understanding the regulation of reproduction in this economically important aquaculture species. In this study, the transcriptomic bases of R. decussatus reproduction have been analysed using a custom oligonucleotide microarray representing 51,678 assembled contigs. Microarray analyses were performed...

14. A numerical model for free infragravity waves: Definition and validation at regional and global scales - Ardhuin, Fabrice; Rawat, Arshad; Aucan, Jerome
The spectral wave model WAVEWATCH III is extended from the windsea and swell band to lower frequencies, in order to represent free waves in the infragravity (IG) wave band. This extension is based on an empirical source of IG energy, which is defined along shorelines from the significant wave height and a mean period. The empirical proportionality factor is found to reproduce accurately the variations of free IG wave energy in coastal areas, where it was calibrated, and also has a good skill at global scales. In the open ocean, the model is particularly verified for frequencies in the range...

15. The gill chamber epibiosis of deep-sea shrimp Rimicaris exoculata: an in-depth metagenomic investigation and discovery of Zetaproteobacteria - Jan, Cyrielle; Petersen, Jillian M.; Werner, Johannes; Teeling, Hanno; Huang, Sixing; Glockner, Frank Oliver; Golyshina, Olga V; Dubilier, Nicole; Golyshin, Peter N.; Jebbar, Mohamed; Cambon-bonavita, Marie-anne
The gill chamber of deep-sea hydrothermal vent shrimp Rimicaris exoculata hosts a dense community of epibiotic bacteria dominated by filamentous Epsilonproteobacteria and Gammaproteobacteria. Using metagenomics on shrimp from the Rainbow hydrothermal vent field, we showed that both epibiont groups have the potential to grow autotrophically and oxidize reduced sulfur compounds or hydrogen with oxygen or nitrate. For carbon fixation, the Epsilonproteobacteria use the reductive tricarboxylic acid cycle, whereas the Gammaproteobacteria use the Calvin–Benson–Bassham cycle. Only the epsilonproteobacterial epibionts had the genes necessary for producing ammonium. This ability likely minimizes direct competition between epibionts and also broadens the spectrum of environmental...

16. Comparative ecology of widely distributed pelagic fish species in the North Atlantic: implications for modelling climate and fisheries impacts - Trenkel, Verena; Huse, G.; Mackenzie, B.r.; Alvarez, P.; Arrizabalaga, H.; Castonguay, M.; Goñi, N.; Grégoire, F.; Hátún, H.; Jansen, T.; Jacobsen, J.a.; Lehodey, P.; Lutcavage, M.; Mariani, Patrizio; Melvin, G.d.; Neilson, J.d.; Nøttestad, L.; Óskarsson, G.j.; Payne, M.r.; Richardson, D.e.; Senina, I.; Speirs, D.c.
This paper reviews the current knowledge on the ecology of widely distributed pelagic fish stocks in the North Atlantic basin with emphasis on their role in the food web and the factors determining their relationship with the environment. We consider herring (Clupea harengus), mackerel (Scomber scombrus), capelin (Mallotus villosus), blue whiting (Micromesistius poutassou), and horse mackerel (Trachurus trachurus), which have distributions extending beyond the continental shelf and predominantly occur on both sides of the North Atlantic. We also include albacore (Thunnus alalunga), bluefin tuna (Thunnus thynnus), swordfish (Xiphias gladius), and blue marlin (Makaira nigricans), which, by contrast, show large-scale migrations at...

17. Estimating the economic loss of recent North Atlantic fisheries management - Merino, Gorka; Barange, Manuel; Fernandes, Jose A.; Mullon, Christian; Cheung, William; Trenkel, Verena; Lam, Vicky
It is accepted that world’s fisheries are not generally exploited at their biological or their economic optimum. Most fisheries assessments focus on the biological capacity of fish stocks to respond to harvesting and few have attempted to estimate the economic efficiency at which ecosystems are exploited. The latter is important as fisheries contribute considerably to the economic development of many coastal communities. Here we estimate the overall potential economic rent for the fishing industry in the North Atlantic to be B€ 12.85, compared to current estimated profits of B€ 0.63. The difference between the potential and the net profits obtained...

18. Origin and Accumulation of Trace Elements in Sediments of the Northwestern Mediterranean Margin - 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,...

19. Mixing parameterization: Impacts on rip currents and wave set-up - Bennis, Anne-claire; Dumas, Franck; Ardhuin, Fabrice; Blanke, Bruno
Wave set-up is often underestimated by the models (e.g. Raubenheimer et al., 2001). Our paper discusses how the wave set-up may be changed by the inclusion of turbulent mixing in the bottom shear stress. The parameterization developed in Mellor (2002) for phase-averaged oscillatory boundary layer is used for this purpose. Two studies are carried out. The dependence of the parameterization on the vertical discretization and on the magnitude of the near-bottom wave orbital velocity is investigated. The function that distributes the turbulent terms over the vertical is modified, giving a good agreement with the average of the phase-resolved velocities, but...

20. Strengths and Weaknesses of the Management and Monitoring of Deep-Water Stocks, Fisheries, and Ecosystems in Various Areas of the World-A Roadmap Toward Sustainable Deep-Water Fisheries in the Northeast Atlantic? - Large, Philip A.; Agnew, David J.; Alvarez Perez, Jose Angel; Barrio Frojan, Christopher; Cloete, Rudi; Damalas, Dimitrios; Dransfeld, Leonie; Edwards, Charles T. T.; Feist, Stephen; Figueiredo, Ivone; Gonzalez, Fernando; Gil Herrera, Juan; Kenny, Andrew; Jakobsdottir, Klara; Longshaw, Matt; Lorance, Pascal; Marchal, Paul; Mytilineou, Chryssi; Planque, Benjamin; Politou, Chrissi-yianna
Scientific interest in deep-water marine resources has increased dramatically over the last 10-20 years as management bodies have sought advice on how to manage deep-water fisheries and protect deep-water ecosystems. The strengths and weaknesses of the management and monitoring of deep-water stocks, fisheries, and ecosystems in various areas of the world are described, with the objective of informing the EU FP7 DEEPFISHMAN project so that it can fulfill its primary aim, which is to develop strategic options for a short-and long-term management and monitoring ecosystem-based framework for the northeast Atlantic. To provide a baseline, the current monitoring and management regime...

Página de resultados:
 

Busque un recurso