Data/hora: 12/06/2024 13:41:17

Provedor de dados: | 5
País: | France
Título: | Approche quantitative de la fonction de nourricerie jouée par les systèmes vasières-estuaires
Autores: | Parlier, Emmanuel.
Data: | 2006-09-22
Ano: | 2006
Palavras-chave: | Isotope ratio; Otolith; Saltmarsh; Nursery; Mont Saint Michel Bay; Saint Brieuc Bay; Aiguillon Bay; Seine estuary; Loire estuary; NEA; Dicentrarchus labrax; Fish communities; Rapports isotopiques; Otolithe; Marais salés; Nourricerie; Baie du Mont Saint Michel; Baie de Saint Brieuc; Baie de l'Aiguillon; Seine; Loire; ANE; Dicentrarchus labrax; Peuplement de poissons.
Resumo: | Coastal fish populations settle more or less frequently, at various stages, estuarine systems. Tidal marshes are one of the components of these mosaics of habitats. The first part of this work describes fish assemblages through the utilisation of these systems by fishes analysed in order to propose a revised functional classification of ecological guilds. T h i s new classification is used to compare fish communities of four estuarine systems in the western coast of France: the Mont Saint- Michel Bay, the Saint-Brieuc Bay, the Loire estuary and the Aiguillon Bay. The second part aims at characterizing the nursery function as defined by Beck et al. (2001). Acombinative approach based on gut content analysis, and stable isotope analysis shows that Yo Y s e a bass (Dicentrarchus labrax) that are caught in tidal marshes feed actively in situ and that the salt marsh preys contribute significantly to the first year food resources. An examination of the microstructure of the Yo Y sea bass otoliths using SEM shows characteristic marks, which are interpreted as fingerprints of the passage in the salt marsh. The microstructural analysis showed that sea bass recruits in estuarine areas after variable length of time (33 days to 126 days) spent in marine waters during migration from spawning areas to estuaries. After entry into estuarine complexes, growth rate increases. Microchemical analysis of the whole otolith using ICPMS technology revealed characteristic signatures of each of the studied estuarine systems. This suggests that the chemical composition of trace elements in the otoliths can be used as a chemical tag of fish.  After a synthesis of this combinative approach, a reflection is committed concerning the efficiency of these approach in order to advise managers. The same though is engaged to evaluat  the sustainabilityof these studies that mix strong field investments and theoretical ecology (guilds, life history traits, etc.).
Tipo: | Text
Idioma: | Francês
Identificador: | http://archimer.ifremer.fr/doc/2006/these-4601.pdf
Editor: | Université de LA ROCHELLE
Relação: | http://archimer.ifremer.fr/doc/00000/4601/
Formato: | application/pdf