臺灣二葉松針葉構造之海拔變異

Structural Variation of the Needles of Pinus taiwanensis Hay. along an Elevational Gradient

許秋容(Chiou-Rong Sheue) ； 楊遠波(Yuen-Po Yang) ； 黃玲瓏(Ling-Long Kuo-Huang)

《台灣林業科學》 15卷3期 (2000/09) Pp. 337-349

https://doi.org/10.7075/TJFS.200009.0337

摘要

臺灣二葉松(Pinus taiwanensis Hayata)廣泛分佈於臺灣中、南部低至高海拔山區。本研究由其分佈的最低海拔(700m)至其分佈的最高海拔(3100m)，分五個海拔高度取樣，觀察、比較並分析不同海拔生育地之針葉的外部形態、內部解剖等特徵，以期瞭解二葉松葉部構造是否具有適應海拔變異之特殊變化，並探討各特徵變異可能隱涵之意義。本研究結果顯示所分析的二十八項特徵均達顯著差異，並且多項特徵與海拔高度的變化呈明顯的相關性，其中葉表氣孔密度、葉寬和厚度、葉面積和非維管束面積、維管束至近軸葉表距離、葉肉細胞間隙、維管束寬／高比、轉輸組織、厚壁細胞和射線篩胞的面積、轉輸薄壁細胞個數、”A”區轉輸組織（環繞於維管束外側，由轉輸薄壁細胞和具重紋壁孔的轉輸管胞所組成）以及遠軸面厚壁細胞等，均隨海拔升高而明顯遞增。至於針葉長度、副細胞數目、維管束跡、維管束內松脂管與”B”區轉輸組織（位於維管束跡和近軸面厚壁細胞之間，僅由不具重紋壁孔的轉輸管胞組成）等，則依海拔升高而明顯遞減。再者，松脂管數目、近軸面兩松脂管腔面積及松脂管與維管束面積等特徵，則以中海拔處的值較大，因此生長在不同海拔高度之臺灣二葉松的針葉結構，有其獨特的調整與適應方式。

關鍵字

臺灣二葉松 ； 針葉 ； 典型判別分析 ； 形態 ； 解剖 ； 海拔變異

並列摘要

Twenty-eight morphological and anatomical characters of mature needles of Pinus taiwanensis Hay. collected from different elevations (700, 1100, 1500, 2500, and 3100 m) were analyzed using canonical discriminate analysis. Most of the characters were related to elevation changes. All of the following characters increased in accordance with increasing elevation: the density of stomata, needle thickness and width, the area of needle transection and nonvascular tissue, the distance between the vascular bundle and adaxial leaf surface, the intercellular space of mesophyll, the ratio of width over height of the vascular bundle, transfusion tissue, sclereids, Strasburger cells, cell number of transfusion parenchyma, the ”A” zone of transfusion tissue (surrounding the abaxial side of vascular traces and consisting of transfusion parenchyma and transfusion tracheids having bordered pits), and abaxial sclereids inside the vascular bundle. However, length of needles, cell number of subsidiary cells, vascular trace, resin duct inside the vascular tissue, and the ”B” zone of transfusion tissue (located between the vascular traces and adaxial sclereids and consisting of only transfusion tracheids without bordered pits) decreased with increasing elevation. There were several characters with a maximum at middle elevations, such as the number of resin ducts and their area, the lumen area of 2 major adaxial resin ducts, and the area of the vascular bundle. This obviously shows that the structures of needles of P. taiwanensis have peculiar, modified variations to adapt to environments at different elevations.

並列關鍵字

Pinus taiwanensis ； needles ； canonical discriminate analysis ； morphology ； anatomy ； altitude variation