Influence de la température et du développement planctonique sur le mécanisme d'accumulation de la matière organique à la surface de la mer

The surface “skin” of the ocean is exposed to very particular conditions (ultra-violet irradiation, oxygenation, bubbling), which produce an accumulation of planktonic constituents. Many important parameters were studied in surface and subsurface waters of an inshore area of the North Mediterranean Sea over a period of 1 year. Differences in temperature and salinity between surface and subsurface layers were observed in the summer. Nitrates and phosphates are more abundant in the surface layer before the plankton bloom. Particulate and dissolved organic matter is 2 to 5 times more abundant in the surface than in the subsurface layer. The plankton bloom, very significant in the surface layer, is succeeded by an accumulation of carbohydrates. The surface microlayer of the sea may be considered a valuable indicator of planktonic development in the euphotic layer.