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Auteur Avadi, A.; Freon, P.; Tam, J.
Titre (up) Coupled ecosystem/supply chain modelling of fish products from sea to shelf : the Peruvian anchoveta case Type Article scientifique
Année 2014 Publication Revue Abrégée Plos One
Volume 9 Numéro 7 Pages
Mots-Clés
Résumé Sustainability assessment of food supply chains is relevant for global sustainable development. A framework is proposed for analysing fishfood (fish products for direct human consumption) supply chains with local or international scopes. It combines a material flow model (including an ecosystem dimension) of the supply chains, calculation of sustainability indicators (environmental, socio-economic, nutritional), and finally multi-criteria comparison of alternative supply chains (e.g. fates of landed fish) and future exploitation scenarios. The Peruvian anchoveta fishery is the starting point for various local and global supply chains, especially via reduction of anchoveta into fishmeal and oil, used worldwide as a key input in livestock and fish feeds. The Peruvian anchoveta supply chains are described, and the proposed methodology is used to model them. Three scenarios were explored: status quo of fish exploitation (Scenario 1), increase in anchoveta landings for food (Scenario 2), and radical decrease in total anchoveta landings to allow other fish stocks to prosper (Scenario 3). It was found that Scenario 2 provided the best balance of sustainability improvements among the three scenarios, but further refinement of the assessment is recommended. In the long term, the best opportunities for improving the environmental and socio-economic performance of Peruvian fisheries are related to sustainability-improving management and policy changes affecting the reduction industry. Our approach provides the tools and quantitative results to identify these best improvement opportunities.
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ISSN 1932-6203 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1145
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Auteur Fouilland, E.; Vasseur, C.; Leboulanger, C.; Le Floc'h, E.; Carré, C.; Marty, B.; Steyer, J.-P.; Sialve, B.
Titre (up) Coupling algal biomass production and anaerobic digestion: Production assessment of some native temperate and tropical microalgae Type Article scientifique
Année 2014 Publication Revue Abrégée Biomass & Bioenergy
Volume Numéro Pages
Mots-Clés Digestates; Extreme natural environments; Wastewaters; chlorophyta; cyanobacteria; microalgae
Résumé Coupling algal biomass production and anaerobic digestion is one of the most promising bioprocesses for economically viable algal production. This study assesses the production rates of some native microalgae growing in media supplemented with algal digestate, urban wastewater or digested sludge. Native microalgal populations isolated from temperate freshwaters (Scenedesmus spp.) and marine ecosystems (Nannochloris spp.) had the highest potential production rates (about 100 mg DW L−1 d−1) with algal digestate at about 20% loading ratio. However, no growth was measured for Nannochloris spp., when the ammonium concentration exceeded 100 mg L−1 although Scenedesmus spp. appeared to be tolerant to higher NH4+ concentrations. Very low production rates, or no growth, were measured when microalgae isolated from high salinity waters (Dunaliella salina, Lyngbya aestuarii) were used, suggesting that populations well adapted to extreme environmental conditions are not suitable candidates for growing on wastewater or anaerobic digestate.
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ISSN 0961-9534 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 494
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Auteur NIEBLAS, A.-E.; DRUSHKA, K.; REYGONDEAU, G.; ROSSI, V.; DEMARCQ, H.; DUBROCA, L.; BONHOMMEAU, S.
Titre (up) Defining Mediterranean and Black Sea Biogeochemical Subprovinces and Synthetic Ocean Indicators Using Mesoscale Oceanographic Features Type Article scientifique
Année 2014 Publication Revue Abrégée Plos One
Volume 9 Numéro 10 Pages 1-13
Mots-Clés
Résumé The Mediterranean and Black Seas are semi-enclosed basins characterized by high environmental variability and growing anthropogenic pressure. This has led to an increasing need for a bioregionalization of the oceanic environment at local and regional scales that can be used for managerial applications as a geographical reference. We aim to identify biogeochemical subprovinces within this domain, and develop synthetic indices of the key oceanographic dynamics of each subprovince to quantify baselines from which to assess variability and change. To do this, we compile a data set of 101 months (2002-2010) of a variety of both “classical'' (i.e., sea surface temperature, surface chlorophyll-a, and bathymetry) and ”mesoscale'' (i.e., eddy kinetic energy, finite-size Lyapunov exponents, and surface frontal gradients) ocean features that we use to characterize the surface ocean variability. We employ a k-means clustering algorithm to objectively define biogeochemical subprovinces based on classical features, and, for the first time, on mesoscale features, and on a combination of both classical and mesoscale features. Principal components analysis is then performed on the oceanographic variables to define integrative indices to monitor the environmental changes within each resultant subprovince at monthly resolutions. Using both the classical and mesoscale features, we find five biogeochemical subprovinces for the Mediterranean and Black Seas. Interestingly, the use of mesoscale variables contributes highly in the delineation of the open ocean. The first axis of the principal component analysis is explained primarily by classical ocean features and the second axis is explained by mesoscale features. Biogeochemical subprovinces identified by the present study can be useful within the European management framework as an objective geographical framework of the Mediterranean and Black Seas, and the synthetic ocean indicators developed here can be used to monitor variability and long-term change.
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Langue Langue du Résumé Titre Original
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ISSN 1932-6203 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1130
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Auteur LELIEVRE, S.; VAZ, S.; Martin, C.S.; LOOTS, C.
Titre (up) Delineating recurrent fish spawning habitats in the North Sea Type Article scientifique
Année 2014 Publication Revue Abrégée Journal Of Sea Research
Volume 91 Numéro Pages 1-14
Mots-Clés Egg Distribution; Glm; Habitat Modelling; North sea; Spawning Grounds; temporal variability
Résumé The functional value of spawning habitats makes them critically important for the completion of fish life cycles and spawning grounds are now considered to be “essential habitats”. Inter-annual fluctuations in spawning ground distributions of dab (Limanda Limanda), plaice (Pleuronectes platessa), cod (Gadus morhua) and whiting (Merlangius merlangus) were investigated in the southern North Sea and eastern English Channel, from 2006 to 2009. The preferential spawning habitats of these species were modelled using generalised linear models, with egg distribution being used as proxy of spawners’ location. Egg spatial and temporal distributions were explored based on six environmental variables: sea surface temperature and salinity, chlorophyll a concentration, depth, bedstress and seabed sediment types. In most cases, egg density was found to be strongly related to these environmental variables. Egg densities were positively correlated with shallow to intermediate depths having low temperature and relatively high salinity. Habitat models were used to map annual, i.e. 2006 to 2009, winter spatial distributions of eggs, for each species separately. Then, annual maps were combined to explore the spatial variability of each species' spawning grounds, and define recurrent, occasional, rare and unfavourable spawning areas. The recurrent spawning grounds of all four species were located in the south-eastern part of the study area, mainly along the Dutch and German coasts. This study contributes knowledge necessary to the spatial management of fisheries resources in the area, and may also be used to identify marine areas with particular habitat features that need to be preserved.
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ISSN 1385-1101 ISBN Médium
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Numéro d'Appel LL @ pixluser @ collection 373
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Auteur CASINI, M.; ROUYER, T.; BARTOLINO, V.; LARSON, N.; GRYGIEL, W.
Titre (up) Density-Dependence in Space and Time: Opposite Synchronous Variations in Population Distribution and Body Condition in the Baltic Sea Sprat (Sprattus sprattus) over Three Decades Type Article scientifique
Année 2014 Publication Revue Abrégée Plos One
Volume 9 Numéro 4 Pages
Mots-Clés
Résumé Spatio-temporal density-dependent processes are crucial regulatory factors for natural populations. However, there is a lack of studies addressing spatial density-dependence in fish growth. A previous investigation has suggested spatio-temporal density-dependence in body condition of Baltic sprat. Here, we used different techniques, such as centre of gravity, distance, and homogeneity indices, to better characterize the spatial and temporal variations in sprat density and body condition in the Baltic Proper. Our results evidenced a negative spatio-temporal co-variation between the centres of gravity of density and maximum condition. In the 1980s-early 1990s both centres were located in the middle of the Baltic Proper. From the mid 1990s the centres progressively separated in space, as the sprat population moved towards the north-eastern Baltic Proper, and the centre of maximum condition towards the south-western areas. Moreover, at low abundances, sprat density and condition were homogeneously distributed in space, whereas at high abundances both density and condition showed pronounced geographical gradients. The ecological processes potentially explaining the observed patterns were discussed in the light of the Ideal Free Distribution theory. We provide evidence that the shift in the spatial distribution of cod, the main predator of sprat, has been the main factor triggering the overall spatial changes in sprat density, and thus condition, during the past thirty years. The spatial indices shown here, synthesizing the spatio-temporal patterns of fish distribution, can support the implementation of the EU Marine Strategy Framework Directive.
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Auteur institutionnel Thèse
Editeur 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 1932-6203 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel LL @ pixluser @ collection 374
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