碩士 / 逢甲大學 / 環境工程與科學所 / 98 / The aim of this study is to investigate particulate concentrations in the surrounding area for Feng Chia Night Market in Taichung metropolitan area. The research design included field collocation for the sampling instrument and 8-hr daytime (7 am to 3 pm) and nighttime (4 pm to 0 am) field sampling for 10 consecutive days (from 03/16/2009 to 03/26/2009). During the 8-hr sampling period, traffic flow entering the night market was also counted.
For the instrumental field collocation, Harvard Impactor (HI) was used as the reference method to evaluate the performance of Harvard Personal Environmental Monitoring Sampler (Harvard PEM) and the portable particle concentration monitor (IAQcheckTM Portable Dust Monitor, series 1.108, GRIMM) for both of 8-hr and 24-hr sampling durations. In addition, stationary monitoring data collected by Taiwan EPA (Zhongming and Situn sites) were compared with the sampling data for Harvard Impactor.
Generally speaking, results of field collocation showed that Harvard PEM and GRIMM monitor had a good correlation with HI for both of 8-hr and 24-hr sampling durations. Lower correlation was found for the 8-hr sampling results, which was not surprised as shorter sampling time could introduce larger sampling variability. In addition, data collected by HI correlated pretty well with the data from Taiwan EPA monitoring stations. Among these two sites, Zhongming-site data associated better with the HI data than Situn-site data, with the R2 values of 0.99 and 0.93 for 24-hr PM2.5 and PM10 concentration, respectively.
During the night market sampling periods, prevailing surface winds for weekday daytime, weekday nighttime, weekend daytime, and weekend nighttime were east-southeast wind (ESE), southeast wind (SE), northeasterly wind (NE) and east-northeast wind (ENE), respectively, with an average wind speed less than 1.50 m/s. The prevailing wind direction for weekdays differed from that for the weekend period.
On the other hand, during the night market sampling periods, there were three peak hours: 8 am to 9 am, 10 am to 2 pm and 5 pm to 8 pm. The main contribution to traffic flow was by motorcycles (70%), followed by passenger cars (from 24.0 to 27.6%). Results also found that the proportion of passenger cars in total traffic flow increased slight during the weekends.
Additionally, higher mean and median particulate concentrations were found in the nighttime sampling periods. High concentrations during the weekday daytime and weekday nighttime sampling periods mainly occurred on 03/26 and 03/20, respectively, while the high levels on weekend were reported on the 03/21. High daytime particulate levels on 03/21 night are related to the crowd and vehicles from school activities, while the passenger cars contributing more to the proportion of total traffic flow might be one of the main reasons for high nighttime levels on 03/21. Finally, during the daytime and nighttime of weekdays, enhanced particulate concentrations were usually found on the main peak hours. The same pattern did not show during the weekends, which might be due to the contribution of vehicle types differing during the weekends.
In summary, results of the current study provided important information regarding particulate air pollution and traffic flows in the Feng Chia Night Market areas.
Keywords: field collocation, night market, particulate concentration, traffic flow
| Identifer | oai:union.ndltd.org:TW/098FCU05515004 |
| Date | January 2010 |
| Creators | Chia-hao Wu, 吳家豪 |
| Contributors | Li-te Chang, 張立德 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 176 |
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