Data/hora: 05/06/2024 06:23:16

Provedor de dados: | 5
País: | France
Título: | Effets des caractéristiques physico-chimiques et biorhéologiques de l'eau sur la physiologie, les performances adaptatives et la sélection de l'habitat chez la sole commune Solea solea (Linnaeus, 1758)
Autores: | Couturier, Christine.
Data: | 2007-07-26
Ano: | 2007
Palavras-chave: | Flatfish; SDA; Growth; Habitat selection; Metabolism; Hypoxia; EPS; Viscosity; Common sole; Poissons plats; SDA; Croissance; Sélection d'habitat; Métabolisme; Hypoxie; EPS; Viscosité; Sole commune.
Resumo: | Shellfish culture can lead to an accumulation of exopolysaccharides (EPS) over the surface of intertidal mudflats. EPS are rheologically active polymers that change water viscosity and water flow over the branchial basket of the juvenile flatfish that colonise intertidal mudflats. The aim of this study was to assess the impact of water EPS content on various aspects of the physiology and behaviour of the common sole Solea solea. Field studies revealed that water total EPS can be up to 15 mg l 1 in the field. In sole juveniles (aged class 0+) ventilatory distress was observed at concentrations above 4 mg l-1, and the intensity of the constraint decreased with fish size. Nonetheless, neither standard metabolic rate nor tolerance of hypoxia were influenced significantly by water EPS content. An inter-specific comparison demonstrated species-specific differences in sensitivity to water viscosity, which may reflect gill surface area because species with high surface areas (plaice, turbot) were more sensitive to than species with low surface areas (sole, solenette). Water O2 concentration was a major limiting factor for sole growth. At 30 % air saturation, sole aerobic scope was reduced by 60 % and this was associated with a significant increase of both duration and the whole energy spend on digesting and assimilating food (SDA). The combined effects of hypoxia and EPS on behavioural habitat selection were surprising. In normoxia, sole preferentially settled on an EPS-free substratum. In hypoxia the sole settled on an EPS-rich substratum, despite the evidence that this was associated with an increased ventilatory workload. Hypotheses were proposed to discuss this point.
Tipo: | Text
Idioma: | Francês
Identificador: | http://archimer.ifremer.fr/doc/2007/these-3461.pdf
Editor: | Université de La Rochelle
Relação: | http://archimer.ifremer.fr/doc/00000/3461/
Formato: | application/pdf