Volume 12, No. 6, December 2012, Pages 1105-1115 PDF(1.12 MB)
Influence of an Asian Dust Storm and Southeast Asian Biomass Burning on the Characteristics of Seashore Atmospheric Aerosols in Southern Taiwan
Jen-Hsiung Tsai1, Kuo-Lin Huang1, Neng-Huei Lin2, Shui-Jen Chen1, Ta-Chang Lin3, Shih-Chieh Chen1, Chih-Chung Lin1, Shih-Chieh Hsu4, Wen-Yinn Lin5
1 Department of Environmental Engineering and Science, National Pingtung University of Science and Technology, Nei-Pu, Pingtung 912, Taiwan
2 Department of Atmospheric Sciences, National Central University, Chung-Li, Taoyuan 320, Taiwan
3 Department of Environmental Engineering, National Cheng Kung University, Tainan 701, Taiwan
4 Research Center for Environmental Changes, Academia Sinica, Nankang, Taipei 115, Taiwan
5 Institute of Environmental Engineering and Management, National Taipei University of Technology, Taipei 106, Taiwan
This study explores the effects of an Asian dust storm (ADS) and Southeast Asian biomass burning on the composition of atmospheric aerosols in the coastal area of southern Taiwan in spring 2010. Coarse and fine particles were collected using two manual dichotomous samplers (Dichots) that were equipped with Teflon and Quartz filters. The results reveal that the concentrations of PM10 and PM2.5 in the ADS period were about twice those before and after this. More than half of water-soluble ions in coarse particles (PM2.5–10) were Cl– and Na+ (sea salt), while 70% of water-soluble ions of fine particles were SO42– and NH4+ (secondary aerosols). The OC/EC ratios of PM2.5 and PM2.5–10 were all above 2.0. Over 98% of the metals in coarse and fine particles were crustal elements (98.1–99.1%), and over 60% of the metals in PM10 were in coarse particles (PM2.5–10). The water-soluble ion, EC, OC, and metal contents in PM2.5 all exceeded those in PM2.5–10. The ADS was associated with higher concentrations of water-soluble ions in PM2.5 and PM2.5–10 than was the non-ADS period, except for K+ in PM2.5–10. ADS most increased the Ca2+ content and concentration, causing a rise in the average concentrations of Ca2+ in coarse and fine particles by factors of 3.0 and 3.2, respectively. In the ADS period, although the OC and EC concentrations of coarse and fine particles increased, the OC and EC contents in these particles decreased. The ADS period was associated with higher metal contents in coarse and fine particles than the non-ADS period, and the increase in PM2.5–10 (more than 2%) exceeded that in PM2.5. In PM2.5–10 and PM2.5, the Ca and Ni contents increased the most, respectively. In addition, the concentrations of the water-soluble ions, EC, OC, and metals in PM2.5–10 and PM2.5 increased, but their contents decreased, while the contents of the other constituents (= total – (water-soluble ions + EC + OC + metals)) in PM2.5–10 and PM2.5 increased. It is also found that Southeast Asian biomass burning is related to the deterioration of the air quality of southern Taiwan.
Asian dust storm; Water-soluble ions; Carbon contents; Metal elements; Southeast Asian biomass burning.