台灣民眾越來越重視空氣中細懸浮微粒(PM2.5)的濃度及其分佈情況,本研究擷取2014年至2016年中部地區10個環保署空氣品質監測站的每日空氣品質監測數據進行分析,探討中部地區PM2.5擴散現象及其可能生成原因。數據顯示台灣中部地區大部分測站PM2.5有逐年微幅降低的趨勢,例如:二林測站2015年相較於2014年降低了15.6%,2016年相較於2015年下降了20.8%。埔里測站2015年相較於2014年降低了4.6%,2016年相較於2015年下降了31.1%。 研究發現中部地區風速影響PM2.5擴散甚鉅,分析數據顯示一旦風速降低,無論都會區或鄉村的所有測站,其PM2.5濃度皆明顯開始累積上升;反之,風速一旦提高,空氣中PM2.5濃度幾乎同步下降。此外,統計數據亦顯示自早上6點起空氣中PM2.5濃度及其他空氣污染物有同步上升的趨勢,一直到凌晨才逐漸降低,可見PM2.5濃度與民眾作息有密切關係,來自汽柴油車輛及產業的污染源可能皆需要有效的管理。
The concentration and distribution of fine particle matter (PM2.5) have been paid attention seriously by Taiwanese. In this study, the daily monitoring data of air quality were collected from 2014 to 2016 at 10 monitoring stations of air quality in the central Taiwan. After data analysis, we discussed the distribution phenomena and possible sources of PM2.5. Results indicated that PM2.5 concentrations at different monitoring stations decreased gradually. For instance, the PM2.5 concentration at Erlin county decreased 15.6% from 2014 to 2015 and 20.8% from 2015 to 2016, respectively. The PM2.5 concentration at Puli county decreased 4.6% from 2014 to 2015 and 31.1% from 2015 to 2016, respectively. Results implied that the PM2.5 distribution was significantly influenced by wind velocity in the central Taiwan. Once the wind velocity declined, the PM2.5 started to accumulate and its concentration increased dramatically regardless of city or countryside. On the contrary, the PM2.5 concentration decreased immediately as the wind velocity decreased. In addition, it can be noticed that the PM2.5 concentration increased with other air pollutants simultaneously from 6 o'clock A.M. and decreased until nighttime. This implied that PM2.5 concentration maybe associated with people daily life and vehicles and industries may need more effective management.