| Summary: | 碩士 === 環球科技大學 === 環境資源管理所 === 99 === This study proceeded samplings of ambient PM10 and PM2.5 using a High-Volume particle sampler during the period of August 2009 to May 2010 at Taisi area. Analysis of mass concentrations and also compositions of the suspended particulate, including water-soluble ions, metal and trace elements were carried out in order to understand the chemical characteristics and the sources of particles.A significant affection of sea breeze was found at Taisi. Na+ and Cl- in PM2.5-10 coming from sea spray occupied 7~8% of the mass concentration, and water soluble Mg2+ associated with the sea was about 1%. Secondary aerosols as NO3-, SO42- and NH4+ accounted for a total portion of 42% in PM2.5. A ratio of [NH4+]eq/[NO3-+ nss SO42-]eq=0.94 indicated the presence of acidic aerosols around Taisi area since there was not enough ammonium to neutralize acids. By the use of enhanced factor analysis, sulphate in PM2.5-10 mainly came from sea spray but not for those in PM2.5. The analysis of metal and trace elements revealed high portion from crust and soil materials. Coarse particles were rich in Al, Fe, Ca and Mg; and fine particles contained large amounts of Zn, Pb and Ni.Air pollution of high level PM2.5 was the most frequent event found at Taisi area, followed by the event of PM10 and then the ozone event. During PM2.5 events, water-soluble ion NO3- was the dominant species, and NH4+ was the second. While at those days of high level PM10, the concentration of crustal materials Ca2+, F- and Mg2+ increased the most, and then of sea spray Na+ and Cl-. During the sampling period, severe situations impacted to the air quality of Taisi region caused by a serious raise of large amounts of sand coming from the river bed of Zhuo-Shui Stream in November 2009, and by a sand storm event in March 2010. During the former event, characteristic species were Al, Fe, Ca, Mg, Ca2+ and Mg2+; and during the latter, those were element Al, Fe and Ca, and water-soluble ions Ca2+ and F-. Both events were associated with the presence of high levels of crust and dust materials, and with an increasing of the transportation of some pollutants.The principal component factor analysis revealed that, in the region of Taisi, the contribution to coarse particles mainly came from soil, sea spray, traffic and road dusts. The contribution to PM2.5 particulate however was associated with artificial activities, including industrial emissions, agricultural activities, and transportation emissions.
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