La matière organique particulaire dans les eaux du bassin de Marennes-Oléron et de ses marais adjacents (claires) : conséquences pour la nutrition de l'huître Crassostrea gigas

In 1979 and 1980, the characteristics of the particulate organic matter are defined fortnightly through seston analyses. It is very high in the basin and very low in the finishing ponds. The phytoplanktonic biomasses are maximal in May in the estuary, and in June-July in the finishing ponds, with chlorophyll contents 10 times higher than those monitored in the basin. Proteins are generally the main biochemical components found in both environments, with glucids accounting for 20 % and lipids for only 10 % of the biochemical components on average. The C/N ratios are almost constant in the finishing ponds with values around 5, typical of phytoplankton, whereas they are very high in the basin except in spring. In the same way, the protid/chlorophyll and the glucid/chlorophyll ratios confirm the detritus trend of the basin.