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A simulation-based approach to assess sensitivity and robustness of fisheries management indicators for the pelagic fishery in the Bay of Biscay ArchiMer
Lehuta, Sigrid; Mahevas, Stephanie; Le Floc'H, Pascal; Petitgas, Pierre.
Indicators are widely promoted as means to monitor ecosystem status or to evaluate fisheries management performance. "Which indicators are most relevant as decision-support tools in fisheries management?" still remains a topical question. Indicators should be metrics related to fish populations and fleets and should be sensitive to management strategies. However, given the complexity of the processes involved, it is often difficult to unequivocally interpret variations in metrics. A simulation approach was used to study metric properties and to identify robust and relevant fishery indicators. By applying sensitivity analysis methods, simulation designs were built that cross a variety of management scenarios and uncertainty hypotheses. Bio-economic outputs...
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Ano: 2013 URL: https://archimer.ifremer.fr/doc/00170/28093/26627.pdf
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Catch-quota balancing in mixed-fisheries: a bio-economic modelling approach applied to the New Zealand hoki (Macruronus novaezelandiae) fishery ArchiMer
Marchal, Paul; Francis, Chris; Lallemand, Philippe; Lehuta, Sigrid; Mahevas, Stephanie; Stokes, Kevin; Vermard, Youen.
Managing adequately the exploitation of commercial species subject to technical interactions is a key step towards the ecosystem approach to fisheries. We evaluate here, using a bio-economic modelling approach building on the ISIS-Fish simulation platform, the relative impact of total allowable commercial catches (TACC) and of taxes applicable to over-quota landings (deemed value) on the sustainability of a selection of species exploited by the New Zealand hoki (Macruronus novaezelandiae) fishery. We investigate some aspects of the hoki mixed fisheries, consisting of four fleets and nineteen metiers, by considering the technical interactions between hoki and Southern hake (Merluccius australis). The dynamics of effort allocation were modelled using gravity...
Tipo: Text Palavras-chave: Fleet dynamics; New Zealand hoki fishery; Deemed value; Fisheries management.
Ano: 2009 URL: http://archimer.ifremer.fr/doc/00000/11168/7521.pdf
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Characterization of sound scattering layers in the Bay of Biscay using broadband acoustics, nets and video ArchiMer
Blanluet, Arthur; Doray, Mathieu; Berger, Laurent; Romagnan, Jean-baptiste; Le Bouffant, Naig; Lehuta, Sigrid; Petitgas, Pierre.
Sound scattering layers (SSLs) are observed over a broad range of spatio-temporal scales and geographical areas. SSLs represent a large biomass, likely involved in the biological carbon pump and the structure of marine trophic webs. Yet, the taxonomic composition remains largely unknown for many SSLs. To investigate the challenges of SSL sampling, we performed a survey in a small study area in the Northern Bay of Biscay (France) by combining broadband and narrowband acoustics, net sampling, imagery and video recordings. In order to identify organisms contributing to the observed SSLs, we compared measured frequency spectra to forward predicted spectra derived from biological data. Furthermore, to assess the confidence in SSL characterization, we evaluated...
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Ano: 2019 URL: https://archimer.ifremer.fr/doc/00588/70035/67955.pdf
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Combining fleet dynamics and population dynamics for a volatile fishery: the example of the anchovy fishery of the Bay of Biscay ArchiMer
Vermard, Youen; Lehuta, Sigrid; Mahevas, Stephanie; Thebaud, Olivier; Marchal, Paul; Gascuel, Didier.
It is increasingly recognized that fisher‟s behavior should be taken into account to understand and predict fishery dynamics, in particular in response to management. ISIS-Fish is a spatially and seasonally explicit modeling framework especially designed to couple populations and fleets dynamics and explore the impact of various management measures on mixed fisheries. It has already been set up using a static fishing effort allocation (corresponding to an average historical pattern) between the various métiers to simulate the pelagic fishery in the Bay of Biscay. We present here the integration of a fleet dynamics model. This model is derived from a Random Utility Model simulating métiers choice using as explanatory variables the past value per unit...
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Ano: 2012 URL: http://archimer.ifremer.fr/doc/00107/21858/19449.pdf
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Combining sensitivity and uncertainty analysis to evaluate the impact of management measures with ISIS-Fish: marine protected areas for the Bay of Biscay anchovy (Engraulis encrasicolus) fishery ArchiMer
Lehuta, Sigrid; Mahevas, Stephanie; Petitgas, Pierre; Pelletier, Dominique.
Spatio-seasonal explicit simulation models can predict the impact of spatial management measures on marine fish populations and fishing activities. As fisheries are complex systems, fisheries simulation models are often complex, with many uncertain parameters. Here, the methodology is provided to deliver fishery diagnostics within an uncertainty context using a complex simulation tool. A sensitivity analysis of the model is performed on model outputs using partial least-squares to identify the most sensitive parameters. The impact of several management measures is then simulated using a statistical simulation design taking into account the uncertainty of the selected sensitive parameters. This approach was applied to the Bay of Biscay anchovy stock using...
Tipo: Text Palavras-chave: Bay of Biscay anchovy; Marine protected area; Sensitivity analysis; Simulation; Uncertainty analysis.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00011/12234/9281.pdf
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Fisheries Management in a Changing Climate Lessons from the 2012 Ocean Heat Wave in the Northwest Atlantic ArchiMer
Mills, Katherine E.; Pershing, Andrew J.; Brown, Curtis J.; Chen, Yong; Chiang, Fu-sung; Holland, Daniel S.; Lehuta, Sigrid; Nye, Janet A.; Sun, Jenny C.; Thomas, Andrew C.; Wahle, Richard A..
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Ano: 2013 URL: http://archimer.ifremer.fr/doc/00168/27912/26194.pdf
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Identification of the main processes underlying ecosystem functioning in the Eastern English Channel, with a focus on flatfish species, as revealed through the application of the Atlantis end-to-end model ArchiMer
Girardin, Raphael; Fulton, Elizabeth A.; Lehuta, Sigrid; Rolland, Marie; Thebaud, Olivier; Travers-trolet, Morgane; Vermard, Youen; Marchal, Paul.
The ecosystem model Atlantis was used to investigate the key dynamics and processes that structure the Eastern English Channel ecosystem, with a particular focus on two commercial flatfish species, sole (Solea solea) and plaice (Pleuronectes platessa). This complex model was parameterized with data collected from diverse sources (a literature review, survey data, as well as landings and stock assessment information) and tuned so both simulated biomass and catch fit 2002–2011 observations. Here, the outputs are mainly presented for the two focus species and for some other vertebrates found to be important in the trophic network. The calibration process revealed the importance of coastal areas in the Eastern English Channel and of nutrient inputs from...
Tipo: Text Palavras-chave: Ecosystem modelling; Flatfish fisheries; Trophic relationships; Calibration; Atlantis; Eastern English Channel.
Ano: 2018 URL: http://archimer.ifremer.fr/doc/00354/46524/46289.pdf
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Impact des mesures de gestion sur la dynamique de la pêcherie pélagique du golfe de Gascogne : Quelles certitudes ? Quels descripteurs ? ArchiMer
Lehuta, Sigrid.
Quantitative evaluations of management measure impact on resource and fleet viability are required to provide diagnostics and feed decision process. Fisheries are complex systems where numerous dynamics interact at various spatial and temporal scales. This complexity and the difficulty to observe marine systems are responsible for the high uncertainty surrounding fishery functioning that makes it hard to identify adequate management measures. The increasing consideration of uncertainties in diagnostics argues in favor of robust management measures rather than optimal management measures. Identifying robust management measures requires the development of models that account for complexity and uncertainty in the description and prediction of management...
Tipo: Text Palavras-chave: Modélisation; Pêcherie mixte; Gestion des pêcheries; Incertitudes; Simulation; Analyse de sensibilité; Indicateurs; Gestion spatialisée; ISIS-Fish; Modeling; Mixed fisheries; Fishery management; Uncertainty; Simulation; Sensitivity analysis; Indicators; Spatialised management; ISIS-Fish.
Ano: 2010 URL: http://archimer.ifremer.fr/doc/00025/13630/10712.pdf
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Impact du changement climatique sur les populations de petits pélagiques des façades françaises. Atleier CERES, éléments de synthèse ArchiMer
Lehuta, Sigrid; Huret, Martin; Issac, Pierre; Petitgas, Pierre.
CERES a pour objectif de mieux comprendre comment le changement climatique influencera les ressources les plus importantes de poissons et de crustacés d'Europe ainsi que les actvités économiques qui en dépendent. CERES fournira des outils et des stratégies d'adaptation permettant aux secteurs des pêches et de l'aquaculture marines et continentales et à leur gouvernance de se préparer aux changements défavorables, ou aux opportunités futures dans certains cas, du changement climatique. IFREMER s'intéresse dans ce projet au cas d'étude de la pêcherie pélagique du golfe de Gascogne, et en particulier aux espèces anchois et sardine. Les changements attendus sur la pêcherie de petits pélagiques concernent (I) la distributon spatiale aux différents stades de...
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Ano: 2018 URL: https://archimer.ifremer.fr/doc/00470/58155/60649.pdf
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Insights from genetic and demographic connectivity for the management of rays and skates ArchiMer
Marandel, Florianne; Lorance, Pascal; Andrello, Marco; Charrier, Gregory; Le Cam, Sabrina; Lehuta, Sigrid; Trenkel, Verena.
Studying demographic and genetic connectivity can help assessing marine meta-population structure. Rays and skates have no larval phase hence population connectivity can only result from active  movement of individuals. Using thornback ray (Raja clavata) in European waters as a case study, demographic  and genetic connectivity were studied for 11 putative populations for unequal population abundances and two  hypotheses of dispersal rates. Genetic simulation results highlighted three large meta-populations: in the  Mediterranean, around the Azores and on the Northeast Atlantic shelf. Demographic results highlighted a finer  population structure indicating that several pairs of putative populations might be demographically linked.  Results were highly...
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Ano: 2018 URL: https://archimer.ifremer.fr/doc/00404/51535/52125.pdf
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Integrated ecological-economic fisheries models-Evaluation, review and challenges for implementation ArchiMer
Nielsen, J. Rasmus; Thunberg, Eric; Holland, Daniel S.; Schmidt, Jorn O.; Fulton, Elizabeth A.; Bastardie, Francois; Punt, Andre E.; Allen, Icarus; Bartelings, Heleen; Bertignac, Michel; Bethke, Eckhard; Bossier, Sieme; Buckworth, Rik; Carpenter, Griffin; Christensen, Asbjorn; Christensen, Villy; Da-rocha, Jose M.; Deng, Roy; Dichmont, Catherine; Doering, Ralf; Esteban, Aniol; Fernandes, Jose A.; Frost, Hans; Garcia, Dorleta; Gasche, Loic; Gascuel, Didier; Gourguet, Sophie; Groeneveld, Rolf A.; Guillen, Jordi; Guyader, Olivier; Hamon, Katell; Hoff, Ayoe; Horbowy, Jan; Hutton, Trevor; Lehuta, Sigrid; Little, L. Richard; Lleonart, Jordi; Macher, Claire; Mackinson, Steven; Mahevas, Stephanie; Marchal, Paul; Mato-amboage, Rosa; Mapstone, Bruce; Maynou, Francesc; Merzereaud, Mathieu; Palacz, Artur; Pascoe, Sean; Paulrud, Anton; Plaganyi, Eva; Prellezo, Raul; Van Putten, Elizabeth I.; Quaas, Martin; Ravn-jonsen, Lars; Sanchez, Sonia; Simons, Sarah; Thebaud, Olivier; Tomczak, Maciej T.; Ulrich, Clara; Van Dijk, Diana; Vermard, Youen; Voss, Rudi; Waldo, Staffan.
Marine ecosystems evolve under many interconnected and area-specific pressures. To fulfil society's intensifying and diversifying needs while ensuring ecologically sustainable development, more effective marine spatial planning and broader-scope management of marine resources is necessary. Integrated ecological–economic fisheries models (IEEFMs) of marine systems are needed to evaluate impacts and sustainability of potential management actions and understand, and anticipate ecological, economic and social dynamics at a range of scales from local to national and regional. To make these models most effective, it is important to determine how model characteristics and methods of communicating results influence the model implementation, the nature of the...
Tipo: Text Palavras-chave: Bio-economic models; Comparative model evaluation; Fisheries management advice; Integrated ecological-economic fisheries models; Marine spatial planning and cross-sector management; Performance criteria and scales and risks; Use and acceptance and implementation and communication and flexibility and complexity.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00391/50269/50898.pdf
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Integrating mark-recapture data within a Bayesian life-cycle model to evaluate spatial structure and population dynamics of sole. A coastal and nursery dependent flatfish : Eastern Channel Sole ArchiMer
Veron, Matthieu; Archambault, Benoit; Rochette, Sebastien; Hunter, Ewan; Lehuta, Sigrid; Randon, Marine; Savina-rolland, Marie; Vermard, Youen; Reveillac, Elodie; Rivot, Etienne; Le Pape, Olivier.
The common sole -Solea solea- is one of the most harvested flatfish population in the Eastern English Channel -EEC; ICES area VIId-. In the EEC, this population is currently assessed and managed as a homogeneous single stock. However, some ecological clues indicate that a metapopulation structure formed by a set of three loosely connected subpopulations associated with local coastal nurseries areas cannot be ruled out. Results show that key estimates of population dynamics parameters, stock assessment and management reference points are highly sensitive to the hypotheses made on the spatial structure. A Bayesian integrated life-cycle model was developed to explore the sensitivity of population dynamics and stock assessment to the level of connectivity in...
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Ano: 2017 URL: http://archimer.ifremer.fr/doc/00410/52134/52844.pdf
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Investigating interconnected fisheries: a coupled model of the lobster and herring fisheries in New England ArchiMer
Lehuta, Sigrid; Holland, Daniel S.; Pershing, Andrew J..
Ostensibly separate fisheries are often linked through ecological, environmental, and human mediated processes that can impact their productivity, profitability, and resilience; however, managers rarely explicitly account for these linkages. We present a coupled bioeconomic model of the American lobster (Homarus americanus) and Atlantic herring (Clupea harengus) fisheries in the northeast United States. The model builds upon existing stock assessment models and includes key characteristics of both fisheries including size- or age-structured populations, seasonal patterns of lobster exploitation, and seasonal-spatial patterns of herring exploitation. The lobster and herring models are linked through a bait market module that drives behavior of the herring...
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Ano: 2014 URL: http://archimer.ifremer.fr/doc/00181/29252/27679.pdf
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Investigating spatial heterogeneity of von Bertalanffy growth parameters to inform the stock structuration of common sole, Solea solea, in the Eastern English Channel ArchiMer
Du Pontavice, Hubert; Randon, Marine; Lehuta, Sigrid; Vermard, Youen; Savina-rolland, Marie.
In fisheries science, a mismatch between the delineation of a fish stock and the underlying biological population can lead to inaccurate assessment and management. Previous results suggested a potential spatial structuration of the Eastern English Channel (EEC) stock of common sole, Solea solea, in three sub-populations. In this article, we propose to investigate the spatial population structure of common sole in the EEC using the von Bertalanffy Growth Function parameters as indicators of population segregation. In order to test the sub-population hypothesis and evaluate its robustness to data sources, we developed three models, all including an area effect on growth parameters. The first model was aimed at testing a potential data source effect (in...
Tipo: Text Palavras-chave: Key-words; Von Bertalanffy growth function; Stock structuration; Solea solea; Flatfish; Life-history traits; Metapopulation.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00445/55625/57301.pdf
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Potential Economic Consequences of the Landing Obligation ArchiMer
Hoff, Ayoe; Frost, Hans; Andersen, Peder; Prellezo, Raul; Rueda, Lucia; Triantaphyllidis, George; Argyrou, Ioanna; Tsikliras, Athanassios; Motova, Arina; Lehuta, Sigrid; Curtis, Hazel; Rodriguez-rodriguez, Gonzalo; Ballesteros, Hugo M; Valeiras, Julio; Bellido, José Maria.
To assess the likely economic outcomes to fishing fleets of the Landing Obligation (LO), bioeconomic models covering seven European fisheries, ranging from the North East Atlantic to the Mediterranean, have been applied to estimate the economic performance of fleets before and after implementing the LO. It is shown that for most of the analysed fisheries, their economic outcome will be negatively affected in the long term by the LO, when compared to the expected outcome with no LO. Efficient mitigation strategies (exemptions, quota uplifts, improved selectivity, effort reallocation and others) may, for some of the analysed fisheries, reduce the negative economic effect of the LO. Moreover, the possibility to trade quotas, both nationally and...
Tipo: Text Palavras-chave: Costs and earnings; Discards; Economic repercussions; Fisheries management; Fleet adjustment.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00473/58435/61010.pdf
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Rapport du projet PECHALO (Pêche Chalutière Occitanie) : Etude de l’impact de l’adaptation des stratégies de pêche et des navires de la flottille chalutière occitane pour améliorer leur viabilité et la durabilité de l’activité ArchiMer
Leforestier, Sophie; Lehuta, Sigrid; Mahevas, Stephanie; Jadaud, Angelique; Vaz, Sandrine.
Dans le Golfe du Lion, le mauvais état des stocks de petits pélagiques a entrainé à partir de 2009 un report de l’activité chalutière pélagique vers les pêcheries démersales. Cette augmentation de la pression de pêche sur les espèces démersales ne facilite pas l’amélioration de l’état de la population de merlu dont le niveau d'exploitation est actuellement 12 fois supérieur au niveau estimé comme durable. En 2018, de nouvelles mesures complémentaires ont été proposées (réduction de l’effort de pêche, fermeture de zones) afin d’assurer un retour au Rendement Maximum Durable du merlu d’ici 2020. Cependant à ce jour les conséquences de ces mesures de gestion sur la pêcherie sont difficilement prévisibles. Une approche basée sur un simulateur de dynamique de...
Tipo: Text Palavras-chave: Pêcherie chalutière; Occitanie; Gestion durable; Viabilité; Merlu; ISISFISH.
Ano: 2020 URL: https://archimer.ifremer.fr/doc/00622/73377/72577.pdf
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Reconciling complex system models and fisheries advice: Practical examples and leads ArchiMer
Lehuta, Sigrid; Girardin, Raphael; Mahevas, Stephanie; Travers-trolet, Morgane; Vermard, Youen.
The move toward an ecosystem-based fisheries management (EBFM) requires new operational tools in order to support management decisions. Among them, ecosystem- and fisheries-based models are critical to quantitatively predict the consequences of future scenarios by integrating available knowledge about the ecosystem across different scales. Despite increasing development of these complex system models in the last decades, their operational use is still currently limited in Europe. Many guidelines are already available to help the development of complex system models for advice yet they are often ignored. We identified three main impediments to the use of complex system models for decision support: (1) their very complexity which is a source of uncertainty;...
Tipo: Text Palavras-chave: Ecosystem-based fisheries management; Complex models; Decision support; Methodological solutions; Participatory modeling; Model sensitivity analysis; Examples.
Ano: 2016 URL: http://archimer.ifremer.fr/doc/00358/46945/46851.pdf
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Selection and validation of a complex fishery model using an uncertainty hierarchy ArchiMer
Lehuta, Sigrid; Petitgas, Pierre; Mahevas, Stephanie; Huret, Martin; Vermard, Youen; Uriarte, Andres; Record, Nicholas R..
Assessing the validity of a model is essential for its credibility especially when the model is used as decision making tool. Complex dynamic fishery models are recommended to investigate the functioning of fisheries and to assess the impact of management strategies, particularly spatial fishing regulations. However, their use is limited due to the difficulty and computational cost of parameterizing and gaining confidence, particularly for parameter rich models. These difficulties are compounded by uncertainty regarding parameter values, many of which are often taken from literature or estimated indirectly. Here we propose a methodology to improve confidence and understanding in the model, easily transferable to any complex model. The approach combines...
Tipo: Text Palavras-chave: Bay of Biscay anchovy; Dynamic fishery model; Model selection; Uncertainty; Validation.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00148/25965/24150.pdf
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State-space modeling of multi-decadal mark-recapture data reveals low adult dispersal in a nursery-dependent fish metapopulation ArchiMer
Lecomte, Jean-baptiste; Le Pape, Olivier; Baillif, Hélène; Nevoux, Marie; Vermard, Youen; Savina-rolland, Marie; Veron, Matthieu; Lehuta, Sigrid; Hunter, Ewan; Rivot, Etienne.
Quantifying connectivity within fish metapopulations is an important component in understanding population dynamics and providing an evidence base for assessment and management. We investigate meta-population connectivity of the common sole (Solea solea L.) in the Eastern English Channel (EEC). The EEC common sole stock is currently assessed as a single and spatially homogeneous population but connectivity induced through adult movements within this stock and with nearby stocks remains unknown. To fill this knowledge gap, we developed a state-space mark-recovery model, designed to estimate adult connectivity, using mark-recapture data from multiple release experiments from 1970 to 2018 across the EEC and adjacent management areas. The model estimates...
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Ano: 2020 URL: https://archimer.ifremer.fr/doc/00515/62634/67003.pdf
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Sustainability Impact Assessment (SIA) in fisheries: Implementation in EU fishing regions ArchiMer
Malvarosa, Loretta; Murillas, Arantza; Lehuta, Sigrid; Nielsen, J. Rasmus; Macher, Claire; Goti, Leyre; Motova, Arina; Doering, Ralf; Haraldson, Gunnar; Accadia, Paolo; Hamon, Katell; Bastardie, Francois; Maravelias, Christos D.; Mardle, Simon; Thøgersen, Thomas.
An Impact Assessment (IA) is a process aimed at structuring and supporting the development of policies. Besides the fact that IA assumes different features when applied to different sectors, really it should help policy makers in evaluating the contribution to the fisheries sustainability of new regulations. The recent improvements and development around the IA methodologies go more and more toward the concept of a Sustainability Impact Assessment (SIA). The evolution of IA in the fishery sector has followed the general and increasing need in having a more and more integrated type of analysis, focusing on the three dimensions of sustainability (environmental, economic and social). This paper synthesizes the methodology developed under the EU FP7 SOCIOEC...
Tipo: Text Palavras-chave: Impact assessment; Fishery management; Effectiveness; Coherence; Acceptability; Sustainability.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00474/58521/65966.pdf
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