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Auteur Andrello, M.; Noirot, C.; Debarre, F.; Manel, S.
Titre MetaPopGen 2.0: A multilocus genetic simulator to model populations of large size Type Article scientifique
Année 2020 Publication Revue Abrégée Mol. Ecol. Resour.
Volume Numéro Pages
Mots-Clés adaptation; connectivity; dispersal; evolutionary; flow; genetic simulator; landscape genetics; mullus-surmuletus; program; spatially explicit
Résumé Multilocus genetic processes in subdivided populations can be complex and difficult to interpret using theoretical population genetics models. Genetic simulators offer a valid alternative to study multilocus genetic processes in arbitrarily complex scenarios. However, the use of forward-in-time simulators in realistic scenarios involving high numbers of individuals distributed in multiple local populations is limited by computation time and memory requirements. These limitations increase with the number of simulated individuals. We developed a genetic simulator, MetaPopGen 2.0, to model multilocus population genetic processes in subdivided populations of arbitrarily large size. It allows for spatial and temporal variation in demographic parameters, age structure, adult and propagule dispersal, variable mutation rates and selection on survival and fecundity. We developed MetaPopGen 2.0 in the R environment to facilitate its use by non-modeler ecologists and evolutionary biologists. We illustrate the capabilities of MetaPopGen 2.0 for studying adaptation to water salinity in the striped red mullet Mullus surmuletus.
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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 1755-098x ISBN Médium
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Notes WOS:000590613600001 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2919
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Auteur Arones, K.; Grados, D.; Ayon, P.; Bertrand, A.
Titre Spatio-temporal trends in zooplankton biomass in the northern Humboldt current system off Peru from 1961-2012 Type Article scientifique
Année 2019 Publication Revue Abrégée Deep-Sea Res. Part II-Top. Stud. Oceanogr.
Volume 169 Numéro Pages Unsp-104656
Mots-Clés anchovy engraulis-ringens; chile; current ecosystem; Decadal trends; diet; Macrozooplankton; Mesozooplankton; Regime-shift; sardine; Secondary production; Spatiotemporal distribution; volume; zone
Résumé Anchovy (Engraulis ringens) is the most important exploited fish species in the Northern Humboldt Current System (NHCS) off Peru. This species, as well as most other pelagic resources, mainly forage on zooplankton. The NHCS is bottom-up controlled at a variety of scales. Therefore, fish biomass is driven by the abundance of their prey. In this context, we studied the spatiotemporal patterns of zooplankton biomass in the NHCS from 1961-2012. Data were collected with Hensen net all along the Peruvian coast. To transform zooplankton biovolume into biomass we used a regression that was calibrated from 145 zooplankton samples collected during four surveys and, for which, precise information was available on both biovolume and wet weight. The regression model was then applied on a time-series encompassing 158 cruises performed by the Peruvian Institute of the Sea (IMARPE) between 1961 and 2012. We observed a clear multidecadal pattern and two regime shifts, in 1973 and 1992. Maximum biomass occurred between 1961 and 1973 (61.5 g m(-2)). The lowest biomass (17.8 g m(-2)) occurred between 1974 and 1992. Finally, the biomass increased after 1993 (26.6 g m(-2)) but without reaching the levels observed before 1973. A seasonal pattern was observed with significantly more biomass in spring than in other seasons. Spatially, zooplankton biomass was higher offshore and in northern and southern Peru. Interestingly, the zooplankton sampling was performed using classic zooplankton net that are well fitted to mesozooplankton and are known to underestimate the macrozooplankton; however, the spatiotemporal patterns we observed are consistent with those of macrozooplankton, in particular euphausiids. This suggests that in the NHCS, when and where macrozooplankton dominates it also dominates the biomass obtained using classic zooplankton net samples. Finally, until now, in the NHCS only time-series on zooplankton biovolume were available. The biomass data we provide are more directly usable in trophic or end-to-end models.
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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 0967-0645 ISBN Médium
Région Expédition Conférence
Notes WOS:000504782200009 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2693
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Auteur Aubert, A.; Antajan, E.; Lynam, C.; Pitois, S.; Pliru, A.; Vaz, S.; Thibault, D.
Titre No more reason for ignoring gelatinous zooplankton in ecosystem assessment and marine management: Concrete cost-effective methodology during routine fishery trawl surveys Type Article scientifique
Année 2018 Publication Revue Abrégée Mar. Pol.
Volume 89 Numéro Pages 100-108
Mots-Clés scyphomedusae; abundance; climate-change; Monitoring; aurelia-aurita; Gelatinous zooplankton; irish sea; Jellyfish; jellyfish blooms; large medusae; Marine management; msfd; northern california current; spatial overlap; surface waters; Trawl
Résumé Gelatinous zooplankton, including cnidarians, ctenophores, and tunicates (appendicularians, pyrosomes, salps and doliolids), are often overlooked by scientific studies, ecosystem assessments and at a management level. Despite the important economic consequences that they can have on human activities and on the marine food web, arguments often related to the costs of monitoring or their coordination, or simply negligence, have resulted in the absence of relevant monitoring programs. A cost-effective protocol has been applied on trawling from existing fishery surveys conducted by national laboratories in England and France. The testing phase has successfully demonstrated the adequacy of such a tool to sample macro- and mega-zooplankton gelatinous organisms in a cost-effective way. This success has led to the acceptance of this protocol into the French implementation of the EU's Marine Strategy Framework Directive (MSFD). Here, a protocol which can be applied to any trawl-based fishery survey and in any new large-scale monitoring program is provided. As an ecosystem approach to marine management is currently adopted, exemplified by the MSFD in Europe, gelatinous zoo plankton should be monitored correctly to prevent a knowledge gap and bias to ecosystem assessments in future.
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Langue English Langue du Résumé Titre Original
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Volume de collection Numéro de collection Edition
ISSN 0308-597x ISBN Médium
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Numéro d'Appel MARBEC @ alain.herve @ collection 2310
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Auteur Authier, M.; Saraux, C.; Péron, C.
Titre Variable selection and accurate predictions in habitat modelling: a shrinkage approach Type Article scientifique
Année 2017 Publication Revue Abrégée Ecography
Volume 40 Numéro 4 Pages 549-560
Mots-Clés account; distributional data; Ecology; indian-ocean; inference; Mediterranean Sea; regression methods; small pelagic fish; spatial autocorrelation; species distribution models
Résumé Habitat modelling is increasingly relevant in biodiversity and conservation studies. A typical application is to predict potential zones of specific conservation interest. With many environmental covariates, a large number of models can he investigated but multi-model inference may become impractical. Shrinkage regression overcomes this issue by dealing with the identification and accurate estimation of effect size for prediction. In a Bayesian framework we investigated the use of a shrinkage prior, the Horseshoe, for variable selection in spatial generalized linear models (GLM). As study cases, we considered 5 datasets on small pelagic fish abundance in the Gulf of Lion (Mediterranean Sea, France) and 9 environmental inputs. We compared the predictive performances of a simple kriging model, a full spatial GLM model with independent normal priors for regression coefficients, a full spatial GLM model with a Horseshoe prior for regression coefficients and 2 zero-inflated models (spatial and non-spatial) with a Horseshoe prior. Predictive performances were evaluated by cross validation on a hold-out subset of the data: models with a Horseshoe prior performed best, and the full model with independent normal priors worst. With an increasing number of inputs, extrapolation quickly became pervasive as we tried to predict from novel combinations of covariate values. By shrinking regression coefficients with a Horseshoe prior, only one model needed to be fitted to the data in order to obtain reasonable and accurate predictions, including extrapolations.
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Langue English Langue du Résumé Titre Original
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Volume de collection Numéro de collection Edition
ISSN 0906-7590 ISBN Médium
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Numéro d'Appel MARBEC @ alain.herve @ collection 2130
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Auteur 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.
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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