Data/hora: 09/06/2024 08:41:13

Provedor de dados: | 5
País: | France
Título: | Programme coordonné Ecotron sur le site d'Arcachon (Aquitaine, France) : contrôle de la production biologique marine dans un écosystème lagunaire aménagé (réservoirs à poissons) - Bilan, synthèse et perspectives
Autores: | Lasserre, Pierre.
Data: | 1979
Ano: | 1979
Palavras-chave: | Lagunes côtières exploitées; Réservoirs à poissons; Bassin d'Arcachon; Fonctionnement écosystème; Contrôle productivité; Modélisation; Développement potentiel; Exploited coastal lagoons; Fish ponds; Arcachon Bay; Ecosystem functioning; Productivity control; Modelling; Potential development.
Resumo: | Coordinated ECOTRON Program on the Arcachon Basin (Aquitaine, France) : Control of marine biological production in a man-modified lagoon ecosystem (fish ponds). Results, synthesis and prospects. The "fish reservoirs" of the Arcachon Basin consist of eutrophic lagoon ecosys­tems, empirically exploited for extensive amphihaline fish culture (grey mullets, sea bass, eels, sea breams). The 1000 hectares of exploited farms, well integrated in a traditional socio-economic context, are presently not adapted for various reasons.The coordinate researches, which have been developed at Arcachon since 1974, within the ECOTRON (CNEXO) Program, show that these highly productive man modified ecosystems are well adapted for the development of semi-intensive aqua­culture. In situ and laboratory studies in the "Domaine de Certes", a 258 ha fish farm, are directed towards the acquisition of a basic ecological knowledge. Our current results are applied to representative production patterns covering 1000 m2to 2 hectares. This research is being developed along complementary axis : (1)  Population dynamics, recruitment, trophic interactions (diatoms, macro­phytes, bacteria, plankton, meiofauna, invertebrate macrofauna, fishes) (2)  Comparative physiological properties of the autochtonous organisms (microflora and meiofauna) and the immigrant species (recruiting in juvenile and adult fish) (3)  Energy relationships and competitive interactions between lower levels (bacteria, diatoms, meiofauna) and upper levels (invertebrate macrofauna, fishes) of the food web, metabolism and energy flow. This research which is complemented by applied programs takes into account energy budgets and in situ metabolic data. Models using the energy circuit language are proposed. They are a useful attempt to simulate the balanced (eutrophy) and unbalanced (dystrophy) functions of the ecosystem. Theoretical and applied considerations show that we can reduce significantly the summer dystrophic crisis by improving the recruitment in predators. These immigrants can change the intrinsically unbalanced structure derived by autoch­tonous populations ("r strategists"). For example, the introduction of juvenile soles into a lagoon impoundment betters (1) trophic interactions, (2) the overall demographic structure and (3) the metabolic balance at the water-sediment inter­face. Semi-intensive sole productions of 500 Kg to 1000 Kg per ha/yr are possible without artifical feeding. A significant improvement in the yield of the cultivated species (soles; sea breams, grey mullets and sea bass to a lesser degree) can be rapidly attained by appropriate fry stocking into certain fish farms of the Arcachon Basin.
Tipo: | Text
Idioma: | Francês

Identificador:

http://archimer.ifremer.fr/doc/00306/41676/40885.pdf

http://archimer.ifremer.fr/doc/00306/41676/

Editor: | Publications du Centre National pour l'Exploitation des Océans (CNEXO). Série : Actes de colloques, n° 7, 1979, pp. 463-502
Formato: | application/pdf

Fonte:

Centre National pour l’Exploitation des Océan, 1979

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