過去有關街道揚塵之研究大都著重在TSP及PM10去除之探討,很少探究道路洗掃前後路旁大氣不同粒徑微粒濃度變化及交通量對路旁大氣懸浮微粒之影響。本研究以分道採樣器(manual dichotomous sampler,簡稱Dichot)及GPS1 PUF SAMPLER(簡稱PS-1)進行道路洗掃前後大氣TSP、粗及細微粒採樣,採得之濾紙樣本分析TSP、粗PM10-100及PM2.5-10及細微粒PM2.5濃度,以探討街道洗掃前後路旁大氣微粒濃度變化及交通量之影響。本研究結果顯示:道路洗掃對路旁大氣粒徑較大懸浮微粒(PM10-100及PM2.5-10)濃度之去除較細微粒(PM2.5)明顯。由車流量對路旁大氣各粒徑微粒濃度之線性迴歸結果發現:路旁大氣TSP測值約有四成四之是與車流量有關聯;車流量對路旁大氣中細微粒(PM2.5)濃度之影響較粗微粒(PM10-100及PM2.5-10)大,車流量之變化可反應約45%PM2.5之關聯性。此結果顯示:道路車流量亦會影響街道附近大氣懸浮微粒濃度及粗細微粒粒徑分佈特性,尤以對細微粒(PM2.5)之影響較大。
Most of street fugitive dust studies focused on TSP and PM10 removal in the past. However, little attention has been paid to influence of street sweeping and traffic flux on roadside atmospheric particle concentrations. In this study, a manual dichotomous sampler (Dichot) and a GPS1 PUF sampler (PS-1) were used to collect atmospheric particles before and after street sweeping for TSP, PM10-100, PM2.5-10, and PM2.5 measurements. The results show that street sweeping removed particles more significantly for large particles (PM10-100 and PM2.5-10) than for fine particles (PM2.5). From the linear regression correlation between traffic flux and particle concentration in different size ranges, it was found that about 44% variance of roadside TSP and 45% variance of PM2.5 were contributed by the traffic fluxes, which however had less influence on the variance of PM10-100及PM2.5-10, implying that the traffic flux influenced the concentrations and coarse/fine size distributions of roadside particles, especially those of the fine particles.