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| Registros recuperados: 31 | |
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| Gros, Philippe. |
| Toward Sustainable Fisheries and Aquaculture in a Changing World Outline · World fish supply: key figures · Global estimates hide marked differences Linkages and dissimilarities between capture and aquaculture A global production sharply unbalanced between geographical areas Bulk of harvest: based on greater diversity of captured species than of farmed ones A globalized fish trade, an uneven food fish consumption between countries · Main causes of bias in official statistics Discards IUU (illegal, unreported, unregulated) fishing · Interactions between fisheries, aquaculture and marine ecosystems Global impacts of marine aquaculture Impacts of fishing on marine biodiversity Implementation of the ecosystem approach to fisheries and... |
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| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00027/13845/10991.pdf |
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| Santarelli, L; Gros, Philippe. |
| The totality of French landings of whelk (Buccinum undatum L.) is assignable to the fisheries of the Normand-Breton Gulf, western Channel. The aim of this paper is to forecast economic rent of the potters of the harbour of Granville, as a function of the two main variates open to supervision: the size of the fishing fleet, and the number of whelk-pots per ship. In order to assess the biological and financial consequences of a prospective development, a deterministic model of the fleet-resource system is proposed. Results of simulations emphasize the sharpness of the rent-dissipation problem under existing tendencies. Therefore some recommendations are put forward to derive a fishery policy that would enable the system to be maintained near optimal... |
| Tipo: Text |
Palavras-chave: Gastropoda; Marine mollusks; Fishery management; Economic models; Fishery economics. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/publication-1786.pdf |
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| Gros, Philippe; Santarelli, Leonardo. |
| The experimental design of the capture field area of baited whelk-pots involves, as a controlled factor, four different spacings between pots (6, 12, 24 and 36m), randomly distributed along a ground line. This spectrum of values is sufficiently broad to preclude overlap of capturing fields of sorne pots. Taking account of the patterns of the M2 tidal currents in the area studied, an ellipse was chosen as a geometrical model of the shape of the capture field. Semimajor and semiminor axes were estimated by least squares, the expected catch per pot being defined as a decreasing function of the area of overlap with adjacent capture fields. · Experimental fishing of Buccinum undatum L. was carried out in the Channel Isles region (Western Channel), and provided... |
| Tipo: Text |
Palavras-chave: Échantillonnage quantitatif; Estimation de densité; Casier appâté; Gestion de stocks; Buccin; Quantitative sampling; Density estimate; Baited pot; Stock assessment; Whelk. |
| Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/00112/22279/19954.pdf |
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| Gros, Philippe; Laurec, A.; Dupouy, Herve. |
| This paper is devoted to statistical problems associated to the estimation of the parameters of a Von Bertalanffy growth curve. A first part corresponds to theoretical considerations, first within the classical regression point of view, corresponding to residuals normaly and independently distributed, then to resampling techniques (Jackknife/Bootstrap). The possibility of using not only the arithmetic mean of observed lengths for a given age, but also medians and modes is discussed. A software has been written in Fortran, which makes it possible to fit by (Weighted) least squares either mean, median or modal length at age, and provides estimates of variances/covariances using the classical approximation within regression theory or resampling techniques. An... |
| Tipo: Text |
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| Ano: 1987 |
URL: http://archimer.ifremer.fr/doc/00394/50575/51267.pdf |
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| Guarini, Jean-marc; Blanchard, Fabian; Bacher, Cedric; Gros, Philippe; Riera, P; Richard, P; Gouleau, D; Galois, R; Prou, Jean; Sauriau, Pg. |
| Microphytobenthos plays an important role as primary producer in shallow embayments subject to a tidal regime. The present paper aims to characterize the spatial patterns of sedimentary chlorophyll a (chl a) biomass in 2 seasons in the wide intertidal mudflats of the Marennes-Oleron Bay (France); furthermore, it provides estimates of total microphytobenthic biomass. Accordingly, a systematic sampling scheme was performed in June 1995 and in January 1996. On average, biomass was higher in June (ca 120 mg chi a m(-2)) than in January (ca 85 mg chi a m(-2)). Moreover, the geostatistical analysis revealed that spatial similarities were propagated over larger distances in June (6 km) than in January (2.2 km). In order to account or this result, we suggest that... |
| Tipo: Text |
Palavras-chave: Microphytobenthos; Chlorophyll a; Spatial distribution; Geostatistics; Intertidal mudflat. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00447/55852/58117.pdf |
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| Gros, Philippe. |
| First analytic approaches in population dynamics modelling did not really begin until the 1920s and 1930s. By the 1950s, models that described how fish populations respond to fishing were developed, and provided useful tools in the management of living resources. These early studies, as well as the bulk of existing theoretical ecology, are usually in spatially homogeneous settings: they deal with temporal processes, and ask specifically about steady-state solutions to nonspatial systems. However, several lines of inquiry have stressed the critical role of spatial complexity when thinking about populations and communities as dynamical systems varying in response to natural or human-created disturbance. The introduction of this report is designed to... |
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| Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/00013/12409/9196.pdf |
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| Blanchard, Michel; Gros, Philippe. |
| Three main intertidal macrofauna communities are identified in Saint-Brieuc Bay: a Macoma balthica community, a Tellina tenuis community; and a third community with Cerastroderma and Tellina tenuis. Physiological parameters such as filtration, respiration and excretion are examined, for the filter-feeding molluscs with the highest biomass (the cockle Cerastoderma edule, the tellinid Tellina tenuis, and the blue mussel Mytilus edulis), either through laboratory experiments, or through previous literature. These results are used together to build up an annual energy budget for the complete soft bottom community, and to observe trophic relations. Results show that the mussel population has a negative influence on the cockle beds that lie just above. |
| Tipo: Text |
Palavras-chave: ENERGY BUDGET; FLUXES; CERASTODERMA-EDULE; TELLINA-TENUIS; SAINT-BRIEUC BAY. |
| Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00100/21132/18752.pdf |
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| Beliaeff, Benoit; Gros, Philippe; Belin, Catherine; Raffin, Bernard; Gailhard, Isabelle; Durbec, Jean-pierre. |
| This study aims to propose a tool to describe the long-term (10 years) variability of phytoplanktonic assemblages monitored by Rephy (French monitoring programme for phytoplankon and phycotoxins) in the English Channel, the Bay of Biscay and the Mediterranean French coastal waters. According to the sampling strategy (systematic survey, with a time-step of 1 or 2 weeks, and a between-sampling station distance ranging from less than one to several kilometres), the information content of the data is mainly relevant to the characterization of seasonal variability of populations at the mesoscale. For any given area, and for each of the 56 taxinomic units considered here, the data are thus processed in order to recognize the temporal succession of ‘phytoplankton... |
| Tipo: Text |
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| Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/00013/12403/9189.pdf |
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| Registros recuperados: 31 | |
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