Major ion composition of wet and dry deposition in the eastern Mediterranean basin

Abstract

Major ions were analysed in wet and dry deposition samples collected for 1 year (1992), using daily and weekly sampling periods at the Eastern Mediterranean coast of Turkey. The dry deposition fluxes of marine and crustal ions were found to be higher than their corresponding wet deposition. However, wet deposition fluxes of ions with anthropogenic sources, such as SO 4 2− and NO 3 − were found to be higher than their dry deposition rates. The annual average pH of the precipitation was 5.17, with high variability in the observed values due to different source regions. High concentrations of SO 4 2− and NO 3 − measured in samples with high pH indicated extensive neutralization of acidity by alkaline species. Results suggest that more than 70% of the acidity has been neutralized by CaCO 3 which originate both from airborne local soil and dust transported from North Africa.