SIGNIFICANCE OF ATMOSPHERIC FALLOUT ON THE UPPER LAYER WATER CHEMISTRY OF THE NORTH-WESTERN MEDITERRANEAN

The atmospheric input is established for almost forty trace and major elements at a coastal site on the North-Western Mediterranean. Compari son with the Rhone River input at the scale of the Gulf of Lions shows that the total atmospheric input dominates for elements of anthropoge nic origin such as Cd, Pb, Sb and Zn. Dissolved input of atmospheric o rigin is very important for these elements and for those of terrigenou s origin (Al and Fe). In the coastal zone, both dissolved external sou rces (atmosphere and Rhone River) can explain the high Mediterranean S urface waters concentrations. Atmospheric input becomes rapidly the pr edominant factor, while the riverine influence being negligible in the few tens' kilometers outside the river mouth.