植栽特性及微氣候條件對薄層式綠屋頂降溫效果之影響

屋頂綠化為全球目前十分普及且鼓勵發展之綠化降溫方式。本研究目的在於探討不同特性之植栽在薄層式綠屋頂之降溫能力及微氣候條件對降溫效果之影響。實驗場地選擇國立臺灣大學造園館屋頂，植栽種類選擇15種不同特性之臺灣原生種植物，針對氣溫、空氣濕度、輻射量、基質濕度、土壤熱通量、反照率、樓板溫度，記錄每5分鐘之平均值，資料分析選用2011年6月至8月每日10時至15時間之數值，而降溫效果為對照組測點溫度減去同時間各測點溫度之差值。研究結果顯示不同植栽在薄層式綠屋頂之降溫效果有顯著差異，進一步分析植栽特性對薄層式綠屋頂降溫效果之影響，結果顯示厚葉、低矮型、細葉或小葉、葉色為綠色之植栽降溫效果顯著較佳，而迴歸分析結果顯示氣溫、輻射量、基質濕度、反照率顯著正向影響降溫效果，而空氣濕度、土壤熱通量顯著負向影響降溫效果。研究結果有助於薄層式綠屋頂建置之植栽選種參考。

關鍵字

選種；氣溫；輻射量；反照率；土壤熱通量

並列摘要

Green roof is a popular environmental friendly technology in cooling worldwide. The aim of this study was to examine different cooling effects of plant characteristics and the effects of microclimatic conditions on cooling. The roofs on Landscape Architecture Building of National Taiwan University were chosen as the study site. Fifteen plants were chosen as study materials. The air temperature, air humidity, radiation, substrate humidity, soil heat flux, albedo and floor temperature were recorded every 5 minutes. The daily data from 10 am to 3 pm between June and August 2011 were used. The differences in temperature between the roof and the plant were taken as cooling effects. Results suggested that there were significant differences between the cooling effects of plants. The plant characteristics including thick leaves, short types, thin leaves, small leaves and green leaves had significant better cooling effects. The results of regression suggested that air temperature, radiation, substrate humidity and albedo had significant positive cooling effects, and the air humidity and soil heat flux had significant negative cooling effects. These results could provide information about species selection on green roof construction.