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Auteur (up) Afandi, I.; Talba, S.; Benhra, A.; Benbrahim, S.; Chfiri, R.; Labonne, M.; Masski, H.; Laë, R.; Tito De Morais, L.; Bekkali, M.; Bouthir, F.Z. url  doi
openurl 
  Titre Trace metal distribution in pelagic fish species from the north-west African coast (Morocco) Type Article scientifique
  Année 2018 Publication Revue Abrégée Int Aquat Res  
  Volume 10 Numéro 2 Pages 191-205  
  Mots-Clés Bioaccumulation; Pelagic fish; South Atlantic coast of Morocco; Trace metals; Upwelling  
  Résumé In the current study, ten elements contents (Fe, Zn, Mn, Cu, Cr, Co, Ni, Cd, Pb and Hg) have been measured in muscle and liver of four pelagic fish species (Engraulis encrasicolus, Sardina pilchardus, Scomber japonicus and Trachurus trachurus) from the north-west African coast (South Atlantic Moroccan coast), collected during summer and autumn seasons (July and December 2013, respectively). Significant differences in metal contents were found between the different species (p < 0.05). Metals levels were also much higher in liver than those recorded in muscle tissues. The concentrations of Fe, Zn, Cd, Co, Cu and Pb were significantly higher in mackerel liver (p < 0.05).While, in muscle, anchovy presents a higher content of Mn, Cu, Cr, Ni and Pb. A high level of cadmium was recorded in liver of the different species which can be attributed to an anthropogenic source (phosphate industry) and to natural sources (upwelling activities). The main concentration of toxic elements (Cd, Pb and Hg) recorded in the four edible muscles of pelagic fish species, under study, were below the established values by the European Commission Regulations and show that their effect on the consumers health can be considered as negligible.  
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  Langue en Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 2008-6970 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2513  
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Auteur (up) Benazzouz, A.; Mordane, S.; Orbi, A.; Chagdali, M.; Hilmi, K.; Atillah, A.; Pelegri, J.L.; Demarcq, H. url  doi
openurl 
  Titre An improved coastal upwelling index from sea surface temperature using satellite-based approach : the case of the Canary Current upwelling system Type Article scientifique
  Année 2014 Publication Revue Abrégée Continental Shelf Research  
  Volume 81 Numéro Pages 38-54  
  Mots-Clés Canary upwelling system; Coastal upwelling; Coastal upwelling index; Remote sensing; Sea surface temperature; West Africa  
  Résumé A new methodology to derive an SST-based upwelling index was based on a rigorous spatial analysis of satellite SST fields and their variability, by referring to previous works, from Wooster et al. (1976) to Santos et al. (2011). The data was precautiously processed by considering data quality aspects (including cloud cover) and the best way to derive accurate coastal SST and its offshore reference. The relevance of the developed index was evaluated by comparing its spatial and seasonal consistency against two wind-based indices as well as with the previous SST-based indices, largely superseding these later ones in term of overall quality and spatio-temporal dynamic. Our index adequately describes the spatio-temporal variability of the coastal upwelling intensity in the Canary Current upwelling system and has the advantage of describing complementary aspects of the coastal dynamics of the region that were not covered by Ekman-based indices. The proposed methodology is generic and can be easily applicable to various coastal upwelling systems, especially the four major eastern boundary upwelling ecosystems.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0278-4343 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 351  
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Auteur (up) Benazzouz, A.; Pelegri, J.L.; Demarcq, H.; Machin, F.; Mason, E.; Orbi, A.; Pena-Izquierdo, J.; Soumia, M. url  doi
openurl 
  Titre On the temporal memory of coastal upwelling off NW Africa Type Article scientifique
  Année 2014 Publication Revue Abrégée J. Geophys. Res.-Oceans  
  Volume 119 Numéro 9 Pages 6356-6380  
  Mots-Clés atlantic; Canary Current; cape blanc region; circulation; Coastal upwelling; eastern boundary; Ekman transport; interannual variability; northwest africa; NW Africa; sea-surface temperature; SST difference; system; temporal memory; water  
  Résumé We use a combination of satellite, in situ, and numerical data to provide a comprehensive view of the seasonal coastal upwelling cycle off NW Africa in terms of both wind forcing and sea surface temperature (SST) response. Wind forcing is expressed in terms of both instantaneous (local) and time-integrated (nonlocal) indices, and the ocean response is expressed as the SST difference between coastal and offshore waters. The classical local index, the cross-shore Ekman transport, reproduces reasonably well the time-latitude distribution of SST differences but with significant time lags at latitudes higher than Cape Blanc. Two nonlocal indices are examined. One of them, a cumulative index calculated as the backward averaged Ekman transport that provides the highest correlation with SST differences, reproduces well the timing of the SST differences at all latitudes (except near Cape Blanc). The corresponding time lags are close to zero south of Cape Blanc and range between 2 and 4 months at latitudes between Cape Blanc and the southern Gulf of Cadiz. The results are interpreted based on calculations of spatial and temporal auto and cross correlations for wind forcing and SST differences. At temporal scales of 2-3 weeks, the alongshore advection of alongshore momentum compensates for interfacial friction, allowing the upwelling jet and associated frontal system to remain active. We conclude that the coastal jet plays a key role in maintaining the structure of coastal upwelling, even at times of relaxed winds, by introducing a seasonal memory to the system in accordance with the atmospheric-forcing annual cycle.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 2169-9275 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1194  
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Auteur (up) Boyd, C.; Grunbaum, D.; Hunt, G.L.; Punt, A.E.; Weimerskirch, H.; Bertrand, S. doi  openurl
  Titre Effects of variation in the abundance and distribution of prey on the foraging success of central place foragers Type Article scientifique
  Année 2017 Publication Revue Abrégée J. Appl. Ecol.  
  Volume 54 Numéro 5 Pages 1362-1372  
  Mots-Clés allocation; ecosystem; fisheries; Guanay Cormorant; guano-producing seabirds; Humboldt Current system; impact; indicators; marine spatial planning; Peruvian Booby; Phalacrocorax bougainvilliorum; predator-prey interactions; prey availability; seabird competition with fisheries; small pelagic fish; Sula variegata; upwelling system; variability  
  Résumé 1. Seabirds and pinnipeds are vulnerable to reductions in prey availability, especially during the breeding season when spatial constraints limit their adaptive capacity. There are growing concerns about the effects of fisheries on prey availability in regions where large commercial fisheries target forage fish. 2. For breeding seabirds and pinnipeds, prey availability depends on a combination of abundance, accessibility, patchiness and distance from the colony. An understanding of the aspects of prey availability that determine foraging success is essential for the design of effective management responses. 3. We used a mechanistic individual-based foraging model based on observed data for two sea-bird species, the Peruvian Booby Sula variegata and Guanay Cormorant Phalacrocorax bougainvilliorum, to simulate the foraging patterns of seabirds feeding on schooling fish. We ran the model over simulated prey fields representing eight possible combinations of high or low prey abundance, shallow or deep prey, and broadly distributed or spatially concentrated prey. 4. The results highlight the importance of the accessibility of prey. Depth distribution was the primary factor determining modelled foraging success for both species, followed by abundance, and then spatial configuration. 5. Synthesis and applications. The individual-based foraging model provides a spatially explicit framework for assessing the effects of fisheries on the foraging success of seabirds and other central place foragers, and for evaluating the potential effectiveness of marine-protected areas and other fisheries management strategies for safeguarding central place foragers in dynamic ecosystems. Our analysis indicates that broad-scale fisheries management strategies that maintain forage fish above critical biomass levels are essential, but may need to be supplemented by targeted actions, such as time-area closures, when environmental conditions lead to low prey abundance or reduce prey accessibility for seabirds or pinnipeds of conservation concern. The individual-based foraging model is adaptable and could be reconfigured for application to other species and systems.  
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  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0021-8901 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2192  
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Auteur (up) Brochier, T.; Lett, C.; Freon, P. url  doi
openurl 
  Titre Investigating the “northern Humboldt paradox” from model comparisons of small pelagic reproductive strategies in eastern boundary upwelling ecosystems Type Article scientifique
  Année 2011 Publication Revue Abrégée Fish and Fisheries  
  Volume Numéro Pages 94-109  
  Mots-Clés Benguela; Californie; Canaries; comparative; Courant; De; Espece; estimation; Etude; Humboldt; Impact; L'Environnement; Marin; Pelagique; Poisson; Reproduction; Stock; upwelling  
  Résumé  
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  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1467-2979 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 124  
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