Characterization of size-differentiated particle composition of ionic species between Taichung Harbor (TH) and WuChi Traffic (WT) near Taiwan Strait during 2004–2005

The characteristics of the ionic species concentrations by using appropriate statistical analysis methods and ionic balance equation were investigated in this paper. Size-differentiated ambient air particulates (atmospheric particulate matter of total suspended particulate TSP), fine particle (particle matter with aerodynamical diameter <2.5 μm, PM2.5), coarse particle (particle matter with aerodynamical diameter 2.5–10 μm, PM2.5–10) were collected during March 2004–January 2005 in Taichung Harbor (TH) and WuChi Traffic (WT) near Taiwan Strait by using PS-1 sampler. The result indicated ionic species SO42− was both the main components on the TSP and fine particulates at TH and WT sampling sites, and the ionic species Ca2+ and NO3− were both the main components on the coarse particulates at TH and WT sampling sites during sampling period. By using the method of ionic balance, the results indicated that sulfate is mostly neutralized by ammonia at TH and WT sampling sites in the coarse particle mode. On the contrary, NH4HSO4 is the dominant component in the fine particle mode at TH and WT sampling sites.