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Auteur (up) Aubin, J.; Fontaine, C.; Callier, M.; Roque d'orbcastel, E. doi  openurl
  Titre Blue mussel (Mytilus edulis) bouchot culture in Mont-St Michel Bay: potential mitigation effects on climate change and eutrophication Type Article scientifique
  Année 2018 Publication Revue Abrégée Int. J. Life Cycle Assess.  
  Volume 23 Numéro 5 Pages 1030-1041  
  Mots-Clés assessment lca; canada; carbon; Carbon sink; Climate change; communities; cultivation; environmental impacts; Eutrophication; lca; life-cycle assessment; Mussel; part; production systems; transfers  
  Résumé Bivalve production is an important aquaculture activity worldwide, but few environmental assessments have focused on it. In particular, bivalves' ability to extract nutrients from the environment by intensely filtering water and producing a shell must be considered in the environmental assessment. LCA of blue mussel bouchot culture (grown out on wood pilings) in Mont Saint-Michel Bay (France) was performed to identify its impact hotspots. The chemical composition of mussel flesh and shell was analyzed to accurately identify potential positive effects on eutrophication and climate change. The fate of mussel shells after consumption was also considered. Its potential as a carbon-sink is influenced by assumptions made about the carbon sequestration in wooden bouchots and in the mussel shell. The fate of the shells which depends on management of discarded mussels and household waste plays also an important role. Its carbon-sink potential barely compensates the climate change impact induced by the use of fuel used for on-site transportation. The export of N and P in mussel flesh slightly decreases potential eutrophication. Environmental impacts of blue mussel culture are determined by the location of production and mussel yields, which are influenced by marine currents and the distance to on-shore technical base. Bouchot mussel culture has low environmental impacts compared to livestock systems, but the overall environmental performances depend on farming practices and the amount of fuel used. Changes to the surrounding ecosystem induced by high mussel density must be considered in future LCA studies.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 0948-3349 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2343  
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Auteur (up) Aumont, O.; Maury, O.; Lefort, S.; Bopp, L. url  doi
openurl 
  Titre Evaluating the Potential Impacts of the Diurnal Vertical Migration by Marine Organisms on Marine Biogeochemistry Type Article scientifique
  Année 2018 Publication Revue Abrégée Global Biogeochemical Cycles  
  Volume 32 Numéro 11 Pages 1622-1643  
  Mots-Clés ecosystem; ocean; biogeochemistry; export; carbon cycle; diurnal vertical migration  
  Résumé Diurnal vertical migration (DVM) of marine organisms is an ubiquitous phenomenon in the ocean that generates an active vertical transport of organic matter. However, the magnitude and consequences of this flux are largely unknown and are currently overlooked in ocean biogeochemical models. Here we present a global model of pelagic ecosystems based on the ocean biogeochemical model NEMO-PISCES that is fully coupled to the upper trophic levels model Apex Predators ECOSystem Model, which includes an explicit description of migrating organisms. Evaluation of the model behavior proved to be challenging due to the scarcity of suitable observations. Nevertheless, the model appears to be able to simulate approximately both the migration depth and the relative biomass of migrating organisms. About one third of the epipelagic biomass is predicted to perform DVM. The flux of carbon driven by DVM is estimated to be 1.05 ± 0.15 PgC/year, about 18% of the passive flux of carbon due to sinking particles at 150 m. Comparison with local studies suggests that the model captures the correct magnitude of this flux. Oxygen is decreased in the mesopelagic domain by about 5 mmol?m?3 relative to simulations of an ocean without DVM. Our study concludes that DVM drives a significant and very efficient flux of carbon to the mesopelagic domain, similar in magnitude to the transport of DOC. Relative to a model run without DVM, the consequences of this flux seem to be quite modest on oxygen, due to compensating effects between DVM and passive fluxes.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0886-6236 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2458  
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Auteur (up) Avadi, A.; Adrien, R.; Aramayo, V.; Freon, P. url  doi
openurl 
  Titre Environmental assessment of the Peruvian industrial hake fishery with LCA Type Article scientifique
  Année 2018 Publication Revue Abrégée Int. J. Life Cycle Assess.  
  Volume 23 Numéro 5 Pages 1126-1140  
  Mots-Clés anchoveta fleet; Biotic resource depletion; biotic resource use; efficiency; Fleet management; Fuel use intensity; impact assessment; indicators; Life cycle assessment; life-cycle assessment; products; stock; sustainability; systems; Trawling  
  Résumé The Peruvian hake (Merluccius gayi peruanus) stock has been in a delicate state in the last decades due to overexploitation combined with adverse climatic events. The stock is showing certain signs of recovery since 2012. This work analyses the environmental impacts of current fleet operations and its likely trend. The fleet was divided into coherent segments, per holding capacity and engine power. The validity of both segmentations, as well as the presence of an effect of economies of scale driving fuel use intensity (FUI), was tested. Life cycle assessment was used to calculate environmental impacts, per individual sampled vessel and per segment, complemented with indicators of energy efficiency and biotic resource depletion. The fleet is highly fuel-efficient (120 kg fuel per tonne fish) when compared with other reported values, despite a large overcapacity that increases the impact of the construction and maintenance phases. Significant inter-annual FUI variations were observed (80.0 kg t(-1) in 2008 to 210.3 kg t(-1) in 2006), but no clear trend. Neither significant differences in FUI among fleet segments nor a clear effect of economies of scale were found (but FUI analysis was based on a small sample of 32 values for nine vessels, two of which had data for a single year). Only the largest vessels, featuring 242 m(3) holding capacity and 850 hp engine power, were found to have lower FUI than any of the other vessels, but no statistical test could be applied to validate this difference. Differences in environmental impacts of individual vessels are mostly dominated by their relative FUI. Fuel use and, to a lower extent, maintenance are the main sources of environmental impacts. The most contributing impacts to ReCiPe single score are climate change, human toxicity and fossil depletion. The fishery's impacts on the biotic natural resource were orders of magnitude higher than many other global hake stocks, due to overexploitation. The environmental impacts of the national hake fleet are relatively low during the study period, despite an overcapacity of the fleet. With the perspective of expanding its operations and obtaining better yields on the eventuality that the stock fully recovers, these impacts should decrease. More research based on additional FUI data is necessary to effectively compare the performance of these vessels with larger ones (featuring > 180 m(3) and > 500 hp, of which nine existed in 2016) before possibly recommending their preferential use.  
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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 0948-3349 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2344  
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Auteur (up) Ayata, S.-D.; Irisson, J.-O.; Aubert, A.; Berline, L.; Dutay, J.-C.; Mayot, N.; Nieblas, A.-E.; D'Ortenzio, F.; Palmiéri, J.; Reygondeau, G.; Rossi, V.; Guieu, C. url  doi
openurl 
  Titre Regionalisation of the Mediterranean basin, a MERMEX synthesis Type Article scientifique
  Année 2018 Publication Progress in Oceanography Revue Abrégée  
  Volume 163 Numéro Pages 7-20  
  Mots-Clés Mediterranean Sea; regionalisation; biogeochemistry; circulation; mesoscale features; epipelagic ocean; management; spatial planning  
  Résumé Regionalisation aims at delimiting provinces within which physical conditions, chemical properties, and biological communities are reasonably homogeneous. This article proposes a synthesis of the many recent regionalisations of the open-sea regions of the Mediterranean Sea. The nine studies considered here defined regions based on different, and sometimes complementary, criteria: dynamics of surface chlorophyll concentration, ocean currents, three-dimensional hydrological and biogeochemical properties, or the distribution of organisms. Although they identified different numbers and patterns of homogeneous regions, their compilation in the epipelagic zone identifies nine consensus frontiers, eleven consensus regions with relatively homogeneous conditions, and four heterogeneous regions with highly dynamical conditions. The consensus frontiers and regions are in agreement with well-known hydrodynamical features of the Mediterranean Sea, which constrain the distribution of hydrological and ecological variables. The heterogeneous regions are rather defined by intense mesoscale activity. The synthesis proposed here could constitute a reference step for management actions and spatial planning, such as the application of the European Marine Strategy Framework Directive, and for future biogeochemical and ecological studies in the Mediterranean Sea.  
  Adresse Center for Prototype Climate Modeling, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, United Arab Emirates  
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  Editeur Elsevier BV Lieu de Publication Éditeur  
  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0079-6611 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 51673 collection 2349  
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Auteur (up) Ba, K.; Thiaw, M.; Fall, M.; Thiam, N.; Meissa, B.; Jouffre, D.; Thiaw, O.T.; Gascuel, D. doi  openurl
  Titre Long-term fishing impact on the Senegalese coastal demersal resources: diagnosing from stock assessment models Type Article scientifique
  Année 2018 Publication Revue Abrégée Aquat. Living Resour.  
  Volume 31 Numéro Pages 8  
  Mots-Clés west-africa; dynamics; management; West Africa; fisheries; overexploitation; marine ecosystems; populations; mauritania; lessons; Bayesian approach; Coastal demersal species; delta-GLM models; epinephelus-aeneus; experience; surplus production models  
  Résumé For the first time in Senegal, assessments based on both stochastic and deterministic production models were used to draw a global diagnosis of the fishing impact on coastal demersal stocks. Based one national fisheries databases and scientific trawl surveys data: (i) trends in landings since 1971 were examined, (ii) abundance indices of 10 stocks were estimated using linear models fitted to surveys data and commercial catch per unit efforts, and (iii) stock assessments were carried out using pseudo-equilibrium Fox and Pella-Tomlinson models and a Biomass dynamic production model fitted in a Bayesian framework to abundance indices. Most stocks have seen their abundance sharply declining over time. All stocks combined, results of stock assessments suggest a 63% reduction compared to virgin state. Three fifth of demersal stocks are overexploited and excess in fishing effort was estimated until 75% for the worst case. We conclude by suggesting that the fishing of such species must be regulated and an ecosystem approach to fisheries management should be implemented in order to monitor the whole ecosystem.  
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  Auteur institutionnel Thèse  
  Editeur Lieu de Publication Éditeur  
  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 0990-7440 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2278  
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