都市街道微氣候與空氣品質及行人舒適感知之研究

Abstract

近年來隨著生活水準的要求提升，人們對於環境舒適性的要求也相對提高，城市中最貼近人的戶外空間莫過於街道，且文獻指出戶外的微氣候產生熱環境，對舒適度有顯著影響，然而除了溫度的影響外，近期有些學者開始討論起環境舒適度的影響因子，如聲音、空氣品質等因素也對環境的舒適感受有所影響，而這部分在國內的研究中較少看到，也鮮少戶外街道的相關研究 。 文獻指出街道的走向、高寬比、植栽綠覆率、天空可視率等因素會影響微氣候，街道寬度、植栽綠化等因素會影響空氣品質，植栽與街道寬度對噪音有影響，不同的街道環境屬性會有不同的微氣候、空氣品質及環境音量，且人對環境舒適的評價受到環境中的熱、空氣品質及聲音等刺激影響，形成熱感知、空氣品質感知、音量感知，因此，本研究認為，戶外街道舒適感受的影響因子應該同時探討環境中的微氣候、空氣品質及環境音量，以瞭解都市街道中微氣候、空氣品質及環境音量對行人舒適感受的影響、各感知與舒適感受的關係，並得知街道環境屬性對熱環境、空氣品質之影響，再於後續歸納出行人感到舒適的街道環境屬性。 本研究以台北市大安區街道為研究地點，根據街道寬度、街道走向、綠覆率、天空可視率及植栽狀況，選定六個研究測點， 觀測不同環境屬性下街道的微氣候、空氣品質及音量，並同時發放問卷， 調查行人對當下環境的熱感知、空氣品質感知、音量感知及整體舒適感受。量測與調查時間為無雨天候的上午8點至下午6點，進一步分析相關性。 結果顯示，在實際量測值方面，不同街道環境屬性有顯著差異，微氣候之量測值與熱感知有顯著相關、環境音量之量測值與音量感知也有顯著相關，但空氣污染物濃度與空氣品質感知在熱季期間沒有發現關係。逐步迴歸之預測模型顯示行人在都市街道上的舒適感受在不同季節會受到不同因子的影響，但影響最大的是空氣品質感知、其次是音量感知、熱感知。若行人認為街道環境的空氣品質良好、環境安靜，整體舒適感受則會提升。而熱感知越小，表示行人感覺越冷時，熱季期間之舒適感受較好，涼季期間則會感到不舒適。 而微氣候、空氣品質與音壓級量測值對整體舒適感受的影響，在涼季期間較明顯，臭氧濃度與一氧化碳濃度越低，會有越好的舒適感受；個人特徵對整體舒適感受的影響，在熱季期間較明顯，身體有不舒服（有症狀）以及有抽菸習慣的人，會比身體無症狀且無抽菸習慣的人，有更不好的舒適感受。 故行人的舒適感受評價受到多種環境感知影響，各感知與實質微氣候、空氣品質及音量有顯著相關，且實質微氣候、空氣品質及音量受到街道環境屬性之影響，因此，在戶外舒適度的評估上應考慮道路環境的規劃或加以改善，以提升人民的生活品質。

With the improvement of living standards, the requirements of environmental comfort also increased. Streets are the most closest outdoor space for people, and the literature points out that outdoor microclimate influences thermal envrionment, which has a significant impact on comfort. In addition to the influence of temperature, some scholars have recently discussed the other factors of environmental comfort, such as sound level, air quality, etc. However, this part is rarely seen in domestic research, and there are few related researches on outdoor streets. The literature indicates that factors such as street orientation, aspect ratio, green coverage, and sky view factor will affect microclimate. Street width, planting and other factors will affect air quality, planting and street width have an impact on noise. The microclimate, air quality and acoustic environment differs from the street environmental attributes, and people’s evaluation of environmental comfort, including thermal perception, air quality perception, and acoustic perception is affected by stimuli such as heat, air quality and sound in the environment. In order to understand the impact of microclimate, air quality and acoustic environment in urban streets on pedestrian comfort, the relationship between perceptions and comfort, and the impact of street environment attributes on thermal environment and air quality, this study considers the factors mentioned above at the same time. This study measured the microclimate, air quality and sound level of the street under different environmental attributes from 8 a.m. to 6 p.m. during the non-rainy weather, and investigate pedestrians’ perception through questionnaires. The results show that the measured value of microclimate is significantly related to thermal perception, and sound level is also significantly related to acoustic perception, but the air quality perception did not find a relationship with the concentration of air pollutants. The predictive model of stepwise regression shows that the overall comfort of pedestrians on urban streets will be affected by different factors in different seasons, but the most influential is air quality perception, acoustic perception and thermal comfort. The comfort of pedestrians is affected by a variety of environmental perceptions. Each perception is significantly related to the actual microclimate, air quality, and sound level. The actual microclimate, air quality, and sound level are affected by the attributes of the street environment. Therefore, the road environment plannings or improvements should be considered in the evaluation of outdoor comfort to improve the quality of life of the people.