THE IMPACTS OF ATMOSPHERICALLY DERIVED METALS ON COASTAL MARINE SYSTEMS

Abstract

The total concentrations of trace metals (Al, Fe, Mn, Co, Na, Cu, Zn, Mo, Ni, V, Cd, Pb) have been determined in the marine aerosol at two contrasting coastal sites, Plymouth UK, (December 2001 to April 2003) and Jeddah, Saudi Arabia (August 2002-January 2004). Trace metal concentrations in the Plymouth urban aerosol were lower (2-13 times) than those observed at other comparative UK. urban locations and generally comparable with those observed at European coastal non-urban locations. Statistically significant differences were found in aerosol metal concentrations associated with populations of contrasting air mass sources (i.e. Atlantic and UK/European), being greatest in the UK/European air mass sector for Al, Fe, Mn, Cd, Mo and Pb, owing to enhanced source emission rates from continental Europe. Based on the current work, refined budgets for Ni and Pb for the English Channel were presented. The budgets clearly indicated the importance of the English Channel sediments as both a sink (Ni) and a source (Pb). Aerosol concentrations in the Red Sea Marine Aerosol (RSMA) for the crustally sourced elements Al, Mn and Fe were higher (typically 2.7-3.1 times) than those detected at other comparative sites (i.e. Eastern Mediterranean). The aerosol population associated with the Middle and Southern Saudi Arabia (SSA) air mass had the greatest concentrations of Al, Fe, Mn and Co, whereas, the lowest were found associated with the open Red Sea (RS) marine aerosol. Summer enhancement of aerosol metals was attributed to seasonal dust resuspension as documented in the literature. Red Sea trace metal budgets were presented and would suggest that the sediments are an important source for all elements to the Red Sea water column except for Co and Cd. This work has, therefore, provided unique insights into influences on the air/sea exchange of trace metals and their subsequent impacts and fates in two contrasting marine systems.

Date of Award	2007
Original language	English
Awarding Institution	University of Plymouth