Consulta: creatorFacets:"Fichet, Denis"
Registros recuperados: 5
Data/hora: 01/06/2024 11:23:31

Stable isotope analysis position of intertidal of food source and trophic nematodes and copepods
Provedor de dados: 5
Autores: Rzeznik Orignac, J; Boucher, G; Fichet, Denis; Richard, P.
Four dominant nematode species and various copepods from an intertidal mudflat in Marennes-Oleron Bay were analyzed for delta C-13 and delta N-15 ratios together with their potential food source, the microphytobenthos. It was shown that microphytobenthic C is passed to nematodes either by grazing or predation on herbivorous meiofauna by other nematodes. Diatoms of different sizes exhibited different C-13 content, which can be reflected in herbivorous meiofauna, such as the nematodes Daptonema oxycerca and Metachromadora remanei and the bulk of copepods, indicating they can select different sizes of diatoms. Results confirm the need to analyze meiofauna feeding habits at the species or genera level since the delta N-15 and delta C-13 signatures differed...
Tipo: Text
Palavras-chave: Stable isotopes; Marennes Oleron; Mudflat; Food web; Benthic diatoms; Microphytobenthos; Meiofauna; Copepods; Nematodes.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4292.pdf

Impact of chronic cadmium exposure at environmental dose on escape behaviour in sea bass (Dicentrarchus labrax L.; Teleostei, Moronidae)
Provedor de dados: 5
Autores: Faucher, Karine; Fichet, Denis; Miramand, Pierre; Lagardere, Jean-paul.
The effect of chronic exposure to a low concentration (0.5 mu g l(-1)) of cadmium ions was investigated on escape behaviour of sea bass, Dicentrarchus labrax, using video analysis. Observations were also performed on the microanatomy of lateral system neuromasts. When fish were exposed for 4 h per day over 8 days to the cadmium ions, most of both types of neuromasts observed remained intact. However, some of them presented damaged sensory maculae. Whereas before cadmium exposure, fish responded positively to nearly all the lateral system stimulations, after exposure they decreased by about 10% their positive responses to Stimulations. From the 15th day after the beginning of cadmium exposure, neuromasts presented progressively less damage, cadmium...
Tipo: Text
Palavras-chave: Bioaccumulation; Escape behaviour; Chronic cadmium exposure; Neuromast; Fish lateral system.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-3939.pdf

Comparative analysis of the food webs of two intertidal mudflats during two seasons using inverse modelling: Aiguillon Cove and Brouage Mudflat, France
Provedor de dados: 5
Autores: Degre, Delphine; Leguerrier, D; Du Chatelet, E; Rzeznik, J; Auguet, Jean-christophe; Dupuy, Christine; Marquis, E; Fichet, Denis; Struski, Caroline; Joyeux, E; Sauriau, Pierre-guy; Niquil, Nathalie.
Inverse analysis was used to model the food webs of two intertidal mudflat ecosystems: Aiguillon Cove (AC) and Brouage Mudflat (BM) (south-western Atlantic coast, France). The aim of the present study is to describe and compare the functioning of these two ecosystems. The method of inverse analysis has been adapted in order to take into account, in a single calculation, two seasons: spring/summer (mid-March to mid-October) and autumn/winter (the rest of the year). Gathering all available data on the two sites, the most important gaps in knowledge were identified with the help of sensitivity analyses: they concerned mainly the exports of material by grazing fish (such as mullet Liza ramada), resuspension of microphytobenthos, and fluxes linked to microfauna...
Tipo: Text
Palavras-chave: Atlantic coast; Sensitivity analysis; Tidal flat; Inverse analysis; Steady state; Food web.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1863.pdf

Qualité des eaux littorales des Pertuis Charentais : Bilan et diagnostic
Provedor de dados: 5
Autores: Rostagno, Bernard; Violleau, Allain; Brun, Céline; Dietrich, Patrice; Fillon, Alain; Goulletquer, Philippe; Guichet, Roger; Kantin, Roger; Legay, Didier; Loubersac, Lionel; Masson, Daniel; Rocher, Gregory; Ryckaert, Mireille; Thomas, Gerard; Fichet, Denis; Guyot, Thierry; Miramand, Pierre; Pigeot, Jacques; Seguignes, Michel.
Cette étude, qui a rassemblé les compétences des instances de l'Etat chargées de la surveillance du milieu littoral (DDE, DDASS, IFREMER, Université de La Rochelle) a permis de dresser, à la veille de l'an 2000, un bilan de la situation environnementale du littoral de la « mer des Pertuis». Ce bilan, diversifié dans sa présentation, passe en revue les points marquants de "l'état de santé" de l'environnement, qu'il s'agisse de pollutions ciblées (chimiques, bactériologiques) ou d'autres nuisances variées. Il met en exergue les points forts et les points faibles en matière d'environnement littoral, et rappelle les efforts mis en oeuvre par les différentes administrations chargées de sa surveillance. Dans un premier temps, plus de 250 références...
Tipo: Text
Palavras-chave: Environnement; Qualité eaux; Littoral; Caractéristiques physiques; Economie; Qualité chimique; Qualité bactériologique; Phycotoxines; Biodiversité; Pollution; Recommandations; Pertuis Charentais; Département Charente-Maritime.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/00072/18371/15943.pdf

Impact of acute cadmium exposure on the trunk lateral line neuromasts and consequences on the "C-start" response behaviour of the sea bass (Dicentrarchus labrax L.; Teleostei, Moronidae)
Provedor de dados: 5
Autores: Faucher, Karine; Fichet, Denis; Miramand, Pierre; Lagardere, Jean-paul.
Behavioural responses of sea bass Dicentrarchus labrax were investigated after exposure to cadmium ions in laboratory-controlled conditions. The aim of this study was to discover whether environmental exposure to cadmium ions inactivates fish lateral line system neuromasts, and to determine the behavioural consequences of such a sensory blockage. For this, fish escape behaviour in response to an artificial water jet was recorded using a 25-frames s(-1) analog video camera before and after cadmium exposure. Experimental set up was tested with fish whose lateral line system was artificially inactivated by antibiotics (gentamicin and streptomycin). Histological analyses with scanning electron microscopy showed antibiotic treatment destroyed lateral line...
Tipo: Text
Palavras-chave: Escape behaviour; C start; Acute cadmium exposure; Neuromast; Lateral line system; Sea bass; Fish.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2283.pdf