Ambient air dry deposition and ionic species analysis by using various deposition collectors in Shalu, central Taiwan

This study describes the chemical composition of dry deposition collected at a highway traffic site in central Taiwan during daytime and nighttime periods by using a dry deposition plate (DDP) and water surface sampler (WSS). In addition, the characterization for mass and water-soluble species of total suspended particulate (TSP), both PM2.5 and PM10, was studied at the study site from August 22 to November 30, 2006. Dry deposition fluxes of ambient air particulates and inorganic species (Na+,NH4+, K+, Mg2+, Ca2+, Cl-, NO3-, and SO42-) were analyzed by Ion Chromatography (DIONEX-100). Results of the particulate dry deposition fluxes and mass concentrations are higher in the water surface sampler with respect to the dry deposition plate used in this study. Statistical results also showed the average dry deposition flux of the ionic species Na+,NH4+, K+, Cl-, NO3-, and SO42- obtained by the DDP and WSS displayed significant differences. Also, the average concentrations of Mg2+ and, Ca2+ were statistically the same at this study site. (c) 2007 Elsevier B.V. All rights reserved.