Comparaison des relations trophiques de Ruditapes philippinarum en milieux estuarien et océanique à partir d'un modèle de croissance

Abstract

A comparison of trophic relationships for Ruditapes philippinarum in estuarine and oceanic areas: the use of a growth model. Trophic relationships in Ruditapes philippinarum were studied in estuarine and oceanic areas of Marennes-Oleron during 1985 and 1986. Principal components analysis (P.C.A.) was used to reveal the fluctuations of the descriptors from the principal axes. Changes in dry weight were predicted in each area through an allometric growth model and were related to the principal axes derived from the P.C.A. The results of the model were used to compare the growth in each area and to point out the descriptors responsible for the discrepancies, such as autumnal blooms or silt resuspension. Attention was paid to the sampling strategy related to the time scale of the phenomena accounting for trophic relationships.