Distribution and transport of dissolved trace metals in the Gulf of Cádiz, Spain

Abstract

The Gulf of Cadiz plays a key role in the exchange of biogeochemical fluxes between the Mediterranean Sea and the Atlantic Ocean through the Strait of Gibraltar. Oceanographers have carried out many investigations in the Gulf of Cádiz on water mass circulation and mass balance of nutrients and carbon. However, despite its importance in the global ocean functioning, studies on trace metals in the Gulf of Cádiz and Strait of Gibraltar waters are very scarce. Here we show the concentrations of dissolved trace metal composition (i.e. Ag, Cd, Co, Cu, Fe, Mo, Ni, Pb and Zn) in the Gulf of Cádiz and Mediterranean Sea surface waters as obtained from 5 oceanographic campaigns. Our results indicate that the Gulf of Cádiz surface water mass is receiving large amounts of trace metals transported by the different rivers that flow into the Gulf of Cádiz. Thus, dissolved trace metals in these waters were highly variable with the highest ranges measured for Co (0.06 – 3.1 nM), Fe (0.6 – 392 nM) and Pb (0.04 – 512 nM).