不同海拔臺灣二葉松光合作用、同化産物累積、形成層活動之季節變化及針葉生長期之差異

Difference of Needle Growth Period and Seasonal Variations on Photosynthesis, Assimilate Accumulation and Cambial Activity of Taiwan Red Pine (Pinus Taiwanensis) Grown in Different Altitude of Taiwan

徐鎮暉(Jen-Huei Shiu) ； 廖天賜(Tien-Szu Liao) ； 翁仁憲(Jen-Hsien Weng)

《中華林學季刊》 38卷3期 (2005/09) Pp. 291-303

https://doi.org/10.30064/QJCF.200509.0004

摘要

為了解生長於亞熱帶高、低海拔針葉樹光合作用之季節變化，及縱向生長和橫向生長期差異，並探討光合產物於不同季節之累積及利用情形，以生長在塔塔地區(23°29'N, 120°53'E, 2600m)及惠蓀林場(24°2'N, 120°59'E, 800m)之臺灣二葉松(Pinus taiwanensis)為材料進行越年之實驗。結果顯示生長於塔塔加地區之臺灣二葉松，其光合能力在入冬後隨著氣溫之降低而減弱，入春後會隨溫度升高而上升，但在4月份又因新梢生長而再度下降。生長於惠蓀林場者因環境之溫度較高，光合能力並未隨溫度之升降而變化，但在乾季則隨降雨量之多寡而呈高低變化。臺灣二葉松在惠蓀林場之萌芽及形成層細胞分裂均在3月開始，塔塔加地區則在4月才開始，造成兩地生育期之不同應是由於溫度及降雨差異所造成。在冬季兩地區植物體內之可溶性糖類均有明顯增加之趨勢，生長於塔塔加地區者應是適應低溫，而生長於惠蓀林場者則應是適應缺水環境。在2-4月植物體內澱粉含量會上升，此時若光合作用能力高則可溶性糖含量不會降低，若光合作用能力因低溫或缺水而降低，則植物會將可溶性糖類轉換為澱粉。以上結果顯示，影響塔塔加及惠蓀林場二地區臺灣二葉松之光合能力的季節變化、碳水化合物的累積利用、萌芽及形成層細胞的分裂之差異的主因為溫度及降雨量。

關鍵字

臺灣二葉松 ； 季節 ； 海拔 ； 光合作用 ； 可溶性糖類 ； 澱粉 ； 針葉生長期 ； 形成層活動

並列摘要

The purpose of this study was to explore the seasonal variations of photosynthesis, longitudinal and radial growth as well as the accumulation of assimilates of conifers in high and low elevation of subtropical Taiwan. Pinus taiwanensis was used as materials. We observed that the photosynthesis of P. taiwanensis in Tatachia site (23°29'N, 120°53'E, 2600 m) was inhibited both by the lo temperature in the winter, and the initial growth of shoot during growing season Because the warmer climate in Huisun site (24°02'N, 120°59'E. 800 m), photosynthesis of P. taiwanensis was not influenced by temperature of different seasons, but it related to rainfall in dry season. The shoot and cambial division of P. taiwanesis in Huisun site usually begin in March, whereas that begins in April in Tatachia site. This difference might be due to the differences in temperature and rainfall of the habitats. It also observed that the seasonal variation of starch and soluble sugar in the branch were related to the period of shoot and cambial division as well as temperature and rainfall. We conclude that the differences of above mentioned physiological characteristics of P. taiwanensis grown in Tatachia and Huisun sites closely relate to temperature and rainfall.

並列關鍵字

Pinus taiwanensis ； Season ； Altitude ； Needle growth period ； Photosynthesis ； Soluble sugar ； Starch ； Cambial activity