查詢結果分析
來源資料
頁籤選單縮合
題 名 | 從微氣象資料推測盤固草牧草地之蒸發散量 |
---|---|
作 者 | 徐森雄; 黃國禎; 王少峰; | 書刊名 | 中華農學會報 |
卷 期 | 154 1991.06[民80.06] |
頁 次 | 頁82-93 |
分類號 | 437.113 |
關鍵詞 | 牧草地; 微氣象; 資料; 蒸發散量; 盤固草; |
語 文 | 中文(Chinese) |
中文摘要 | 盤固草(Digitaria decumbens)為臺灣常見之牧草,經選擇臺灣南部,國立屏東農專校區內約40內頃之盤固草牧草地,自1988年7月,每間隔三月分一次,每次4~6天從事微氣象觀測,爾後分析其微氣候特性,並利用觀測所得氣象資料依熱收支法、改良彭曼模式法及蒸發皿係數法推測牧草地之蒸發散量、其結果摘要如下: 1.不論牧草之高矮,其最高溫度均出現在植生群落上,即能動面隨植株高矮而移動,地溫日變化所及深度在20~30cm間。 2.日射之反射率無甚季節變化,平均0.23。 3.淨輻射量約佔全天日射量之69%,兩者之相關係數高達0.99。 4.晝間熱支項之分配,潛熱大於影熱,鮑溫比在0.2~0.6間變化。 5.潛熱佔淨輻射之比率在53.1~70.7%間,平均64.3%。 6.熱收支法推測之蒸發散量,隨天氣而有很大之變化,10~1月間晴天(日射量約250 ly/day)之平均值為1.8mm/day,4~7月間晴天(日射量約為430 ly/day)之平均值為3.7mm/day。 7.盤固草牧草地之蒸發散量可以大型蒸發皿之蒸發量乘上0.6來推測,其對熱收支法推測值之平均誤差為0.38mm/day,而對改良彭曼模式法者為0.23mm/day。 8.熱收支法、改良彭曼模式法及蒸發皿係數法推測值彼此間之相關係數俱在0.87以上,達1%之顯著水準,因此這三種方法均可適用於推測臺灣南部盤固草牧草地之蒸發散量。 |
英文摘要 | Pangola grass (Digitaria decumbens) is a forage species grown widely in Taiwan. The micrometeorological characteristics and evapotranspiration of pangola pasture were studied. It was based on the micro-meteorological observation in National Pingtung Istitute of Agriculture. The results were obtained from October 1988 July 1989 and summarized as follows: 1. The daily mean of albedo was 0.23, and the net radiation (Rn) was about 69% of the global solar radiation (Rs) in pangola pasture. 2. The latent heat flux (1E) was larger than sensible heat flux (L) in Rn rearrangement. The proportion of 1E to Rn was changed from 53.1% to 70.7%, and the Bowen ratio was changed from 0.2 to 0.6. 3. The daily mean of evapotranspiration estimated by heat balance method during the period from October 1988 to January 1989 was 2.2 mm/day when Rs was about 250 ly/day, and that during the period from April to July 1989 was 3.9 mm/day when Rs was about 430 ly/day. 4. The evapotranspiration of pangola pasture could be estimated frome vporation value of A-pan and multiplied by 0.6. 5. mean errors of evapotranspiration values estimated from the modified Penman model method and pan coefficient method were 0.38 and 0.23 mm/day, respectively, compared to that estimated from heat balance method. The correlation coefficients among these three methods were more than 0.87 (P<0.01). It showed that these methods could be used to estimate evapotranspiration from pan-gola pasture in southern Taiwan. |
本系統中英文摘要資訊取自各篇刊載內容。