Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/33280
標題: Estimation of Evapotranspiration in Guandaushi Forest Watershed
關刀溪森林集水區之蒸發散量推估
作者: Huang, Yui-Ching
黃裕群
關鍵字: Evapotranspiration;蒸發散;Water Balance method;Heat method;Aerodynamic method;水平衡法;熱平衡法;空氣動力學法
出版社: 水土保持學系
摘要: 
Evapotranspiration including evaporation of free water surface , soil and transpiration of forest plants , is an important factor to relate with the forest hydrology and climate . Using , it is difficult to measure the evapotranspiration of forest directly . Basing on the conservation and transformation of energy and mass , this study tries to estimate the evapotranspiration of Guandaushi forest watershed with three methods : which are water balance method , heat balance method and aerodynamic method . And the analyzed results are as follows :
1. The average annual evapotranspirations estimated in Guandaushi forest watershed between Jan,1996 and Jun,1999 , are 1,919.0mm by water balance method , 1,127.7mm by heat balance method , and 1,419.5mm by aerodynamic method .
2. The evapotranspiration estimated by heat balance method shows a more reasonable value on monthly distribution , and the average annual evapotranspiration is closed to the value estimated by Guo-wen-sho .
3. According to the long-term weather observation data at Sun-moon Lake , Mt. Ali and this experimental area . The variation tendencies of monthly evapotranspiration at these three object stations are quite similar . It's practicable to apply the tendency of monthly evapotranspiration as reference to measure out the monthly variation of evapotranspiration in the mountain areas of Mid-Taiwan .
4. The under-estimation of evapotranspiration during June to August because of less global radiation induced by raining , can be adjusted by using Thornthwaite method .

蒸發散包含自由水面之蒸發與植物之蒸散,為影響森林水文與氣候重要因子之一,由於森林之植物種類繁多,植生環境複雜,以致於大面積之蒸散量不易由儀器直接測得。因此,本研究根據質能守恆原理及質能轉移之機制,選擇以台灣中部關刀溪森林集水區為試驗集水區,藉由氣象與水文之觀測資料,以水平衡法、熱平衡法及空氣動力學法並參考氣象局位於中部山區之觀測站資料,嘗試推估集水區之蒸發散量,茲將其結果摘要如下:
一、 本集水區自1996年1月至1999年6月間之平均年蒸發散量以水平衡法估算結果為1,919.0mm,以熱平衡法估算結果為1,127.7mm,以空氣動力學法估算結果為1,419.5mm。
二、 本試區以熱平衡法所推估之蒸發散量在各月的分布上較為合理,且熱平衡法所推估之年蒸發散量亦接近於郭文鑠(1978)所推估之本區蒸發散潛勢。
三、日月潭、阿里山及本試區之長期氣象觀測資料,以Thornthwaite法估算蒸發散量之結果,發現三站之月蒸發散量分布趨勢極為相近,可見此一蒸發散量之月分布趨勢應可做為台灣中部山區蒸發散量月變動情形之參考。
四、6至8月間可能因降雨較多導致日射量偏低所造成蒸發散量低估之情形,可採用Thornthwaite法之月蒸發散量推估予以修正。
URI: http://hdl.handle.net/11455/33280
Appears in Collections:水土保持學系

Show full item record
 

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.