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| Riera, Pascal. |
| This study examined the delta(15)N of suspended and sedimented particulate organic matter, primary sources of organic matter and benthic invertebrates along an estuarine gradient in Marennes-Oleron Bay, France. Particular emphasis was given to the use of delta(15)N as a tracer of the origin of organic matter and as a means of determining the benthic food web structure in estuarine environments. delta(15)N values indicated that there was direct utilisation of benthic diatoms as a food source by oyster Crassostrea gigas near intertidal mudflats but suggested trophic mediation between terrestrial detritus and oysters in the upper estuarine reaches. delta(15)N data showed that the trophic position of oysters may vary in the estuarine bay. The delta(15)N values... |
| Tipo: Text |
Palavras-chave: Nitrogen isotope ratio; Particulate organic matter; Crassostrea gigas; Benthic food web; Estuary; Marennes-Oleron Bay. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00448/55926/57786.pdf |
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| Feuillet-girard, Michelle; Gouleau, Dominique; Blanchard, Gérard; Joassard, Lucette. |
| Fluxes of nutrients (NH sub(4) super(+), NO sub(3) super(-), PO sub(4) super(3-) and Si(OH) sub(4)) were studied on an intertidal mudflat in Marennes-Oleron Bay, France, at two different seasons and at different times of the emersion period. Fluxes through the sediment-water interface were both calculated from vertical profiles of nutrient concentration in pore-water (diffusive fluxes, JD) and measured in light and dark benthic mini-chambers (measured fluxes, J sub(0)). Results indicate that ammonia was mainly released in summer while nitrate was mainly taken up in late winter. This uptake from the overlying water was probably due to the coupling of nitrification-denitrification within the sediment. The J sub(0) /J sub(D) ratio further indicates that... |
| Tipo: Text |
Palavras-chave: Estran vaseux; Flux de nutriments; Microphytobenthos; Bioturbation; Marennes-Oléron; Intertidal mudflat; Nutrient fluxes; Microphytobenthos; Bioturbation; Marennes-Oleron Bay. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00038/14893/12220.pdf |
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| Moal, Jeanne; Samain, Jean-francois; Le Coz, Jean-rene; Daniel, Jean-yves. |
| Crassostrea gigas oysters cultivated in Marennes-Oleron Bay (France), face seasonal variations in the environment: salinity, turbidity, phytoplanktonic production, and the tidal rhythm of emersion. The oysters are maintained at different depths to reduce competition for space (e.g. by settlement of mussel spat). The physiological responses of two groups of oysters to different periods of emersion were studied using a seasonal sampling strategy: one group was on a flat part of the area, and the effect of emersion was studied in a short time survey (less than three hours emersion at low tide); the other was located in a very narrow place with a steep slope. This group was subdivided into three, according to bathymetric position, to study the long term effect... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Physiology; Emersion; AEC; Digestive enzimes; Marennes-Oleron Bay. |
| Ano: 1989 |
URL: http://archimer.ifremer.fr/doc/00038/14885/12208.pdf |
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