NUTRIENTS AND TRACE-METALS IN THE NORTHWESTERN MEDITERRANEAN UNDER COASTAL UPWELLING CONDITIONS

Salinity, temperature, turbidity, nutrients and iron, manganese and copper were measured in 50 surface water samples collected from the Rhone river and river plume,the Gulf of Lions and along a vertical profile in the open northwestern Mediterranean. The data obtained bring new information on the distribution of nutrients and trace metals in the northwestern Mediterranean under wind induced coastal upwelling. Persistent northwesterly winds lead to complex physical processes such as upwelling along the northwestern coast of the Gulf, local eddies and oscillating currents. These processes result in the redistribution of dissolved and particulate components, enriched in the upwelling water, throughout the water column. The effect of nutrient-enriched upwelling water on the primary production of the Gulf is expected to be of secondary importance relative to the river input.