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| Registros recuperados: 14 | |
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| Jac, Cyrielle; Desroy, Nicolas; Certain, Gregoire; Foveau, Aurelie; Labrune, Céline; Vaz, Sandrine. |
| By relating observed changes to the pressures suffered, the Marine Strategy Framework Directive intends to better control the factors of environmental degradation and to manage their consequences in European waters. Several descriptors are defined within the framework of the MFSD and in particular descriptor 1 relating to the biological diversity of the seabed and descriptor 6 relating to the seabed integrity (i.e. the quality of their structures and functions). For each descriptor, indicators and threshold values must be defined and a novel conceptual approach to define and detect seabed integrity thresholds is proposed here. Bottom trawling being the main source of shelf continental disturbance, it is important to evaluate its impact on benthic habitat.... |
| Tipo: Text |
Palavras-chave: GES; Threshold values; Trawling impact; Indices; MFSD. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00634/74575/74464.pdf |
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| Jac, Cyrielle; Desroy, Nicolas; Certain, Gregoire; Foveau, Aurelie; Labrune, Céline; Vaz, Sandrine. |
| The benthic fauna of European continental shelves is a severely impacted community, mostly due to intense bottom trawling activity. Trawling effect may be dependent on the spatial and temporal distribution of abrasion, the habitat type including natural perturbation intensity and the fishing gear used. Nonetheless, there is an urgent need to identify or develop indices likely to measure the effect of trawling. For this purpose benthic fauna by-catch monitored in scientific trawl surveys carried out in all European waters in the frame of the Common Fishery Policy Data Collection Multiannual Program may be used. Benthic invertebrates data used in this study were collected during scientific bottom trawl surveys covering the English Channel, the North Sea and... |
| Tipo: Text |
Palavras-chave: Benthic sensitivity; Trawling effect; Indices; Seabed integrity; MSFD. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00635/74693/74606.pdf |
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| Lassalle, G.; Lobry, J.; Le Loc'H, F.; Bustamante, Paco; Certain, Gregoire; Delmas, Daniel; Dupuy, C.; Hily, Christian; Labry, Claire; Le Pape, O.; Marquis, Elise; Petitgas, Pierre; Pusineri, Claire; Ridoux, Vincent; Spitz, J.; Niquil, Nathalie. |
| The Bay of Biscay (North-East Atlantic) has long been subjected to intense direct and indirect human activities that lead to the excessive degradation and sometimes overexploitation of natural resources. Fisheries management is gradually moving away from single-species assessments to more holistic, multi-species approaches that better respond to the reality of ecosystem processes. Quantitative modelling methods such as Ecopath with Ecosim can be useful tools for planning, implementing and evaluating ecosystem-based fisheries management strategies. The aim of this study was therefore to model the energy fluxes within the food web of this highly pressured ecosystem and to extract practical information required in the diagnosis of ecosystem state/health. A... |
| Tipo: Text |
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| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00057/16851/14329.pdf |
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| Bitetto, Isabella; Romagnoni, Giovanni; Adamidou, Angeliki; Certain, Gregoire; Di Lorenzo, Manfredi; Donnaloia, Marilena; Lembo, Giuseppe; Maiorano, Porzia; Milisenda, Giacomo; Musumeci, Claudia; Ordines, Francesc; Pesci, Paola; Peristeraki, Panagiota; Pesic, Ana; Sartor, Paolo; Spedicato, Maria Teresa. |
| The state of marine systems subject to natural or anthropogenic impacts can be generally summarized by suites of ecological indicators carefully selected to avoid redundancy. Length-based indicators capture the status of fish community structure, fulfilling the Marine Strategy Framework Directive (MSFD) requirement for Descriptor 3 (status of commercial fish species). Although the MSFD recommends the development of regional indicators, a comparison among alternative length-based indicators is so far missing for the Mediterranean Sea. Using principal component analysis and dynamic factor analysis, we identified the most effective subset of length-based indicators, whether or not based on maximum length. Indicator trends and time series of fishing effort and... |
| Tipo: Text |
Palavras-chave: Demersal fish community; Size structure indicators; Geographical sub-area; Marine Strategy Framework Directive; Dynamic factor analysis; Redundancy analysis. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00599/71148/69466.pdf |
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| Peristeraki, Panagiota; Bitetto, Isabella; Carbonara, Pierluigi; Carlucci, Roberto; Certain, Gregoire; De Carlo, Francesco; Gristina, Michele; Kamidis, Nikos; Pesci, Paola; Stagioni, Marco; Valls, María; Tserpes, George. |
| Mean temperature (MTC) and mean trophic level (MTL) spatiotemporal patterns of MEDITS survey catches were examined in 13 geographic statistical areas (GSAs) of the Mediterranean between 1994 and 2016. The study aimed to detect changes in the demersal community structure related to anthropogenic impacts. A generalized additive modelling approach was used to examine the effects of year and GSA on the MTC and MTL indexes and on bottom temperature by haul. For the MTC index, the year was significant only in 4 GSAs, while for MTL it was significant in 5. Higher MTC values were observed in central and eastern areas. Bottom temperature increased after 2010, and also from west to east and from north to south. Our results indicate that the recently observed... |
| Tipo: Text |
Palavras-chave: Mean temperature of the catch; Trophic level; Bottom temperature; Trends; Mediterranean; Fishing pressure; Sea warming; Climate change. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00489/60054/63332.pdf |
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| Certain, Gregoire; Barraquand, Frederic; Gardmark, Anna. |
| 1.Multivariate autoregressive (MAR) models are an increasingly popular technique to infer interaction strengths between species in a community and to predict the community response to environmental change. The most commonly employed MAR(1) models, with one time lag, can be viewed either as multispecies competition models with Gompertz density‐dependence or, more generally, as a linear approximation of more complex, nonlinear dynamics around stable equilibria. This latter interpretation allows for broader applicability, but may come at a cost in terms of interpretation of estimates and reliability of both short‐ and long‐term predictions. 2.We investigate what these costs might be by fitting MAR(1) models to simulated two‐species competition,... |
| Tipo: Text |
Palavras-chave: Forecasting; Interaction strength; MARSS; Multivariate autoregressive models; PRESS perturbation. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00439/55085/56521.pdf |
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| Registros recuperados: 14 | |
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