Some aspects of the chemical composition of plankton from the North-Western Mediterranean Sea

Plankton samples were collected from different parts of the Liguro-Provençal Basin during 1979 and 1980 (nearshore and open waters, respectively). Carbon, nitrogen, phosphorus, silicium, aluminium, iron, manganese, zinc, copper, cadmium and mercury concentrations have been determined in these samples. The species composition of plankton has been studies. The results indicated that species composition as well as sampling dates and location are factors of great importance when considering the chemical composition of plankton. Carbon, nitrogen and phosphorus concentrations display variations, but their ratios appear to be almost constant in the various samples. The other elements, except zinc, seem to be less concentrated in plankton from open waters than from coastal waters. The concentrations found are in good agreement with those reported in the literature by various authors.