桃芝颱風所引起土石流對人工林台灣杉性質之影響

Influence of Taiwania Plantation Trees Properties by Toraji Typhoon Debris Flow

王松永(Song-Yung Wang) ； 張上鎮(Shang-Tzen Chang) ； 陳勁豪(Jin-Hau Chen) ； 鄭森松(Sen-Sung Cheng) ； 林法勤(Far-Ching Lin) ； 洪崇彬(Chung-Pin Hung)

《國立臺灣大學生物資源暨農學院實驗林研究報告》 19卷4期 (2005/12) Pp. 261-269

https://doi.org/10.6542/EFNTU.200512_19(4).0002

摘要

The purpose of this study was to investigate the influences of Toraji typhoon debris flow in July 29-30, 2001 on the properties of Taiwania plantation trees in Sitou Tract, Experimental Forest, National Taiwan University. In the study, three plots (A, B, C) were setup, depended on the distance to debris flows, to sample trees based on three different damage levels. Nondestructive test method was also applied on the evaluation of wood properties in July and August, 2003 and the component and yield of the essential oil of leaves were analyzed to understand the influences of debris flow.
Results shown that average DBH of three plots varied as A＞B＞C, however, both their transversal and longitudinal ultrasonic wave velocities (Vt and V(subscript L)) at the DBH position were C＞B＞A and both the transversal and longitudinal velocities of C plots is significantly different from those of A and B plots. The greater distance to the boundary of debris flow, the larger DBH and the lower ultrasonic wave velocity were found. With respect to difference among upper, middle, and lower area of plots along the debris flow, the longitudinal velocities for trees were significantly influenced in the upper area than those from middle and lower area of the A plot. The narrow ring width was occurred in the A plot in 2001, as in B and C plots. However, it continued in both B and C plots in the next year.
Results also shown that the yields of essential oils from the leaves of Taiwania in the A, B, and C plots were 0.10%, 0.16%, and 0.18%, respectively. In addition, the major content of three essential oil were identified as δ-cadinene by using GC-MS, and its relative content was 20.31%, 25.39%, and 28.49%, respectively. These results revealed that both the yields of essential oil and relative content of their major constituent were significantly influenced by the debris flows.

關鍵字

台灣杉 ； 土石流 ； 胸高直徑 ； 年輪寬 ； 氣相層析－質譜儀 ； 超音波速

並列摘要

The purpose of this study was to investigate the influences of Toraji typhoon debris flow in July 29-30, 2001 on the properties of Taiwania plantation trees in Sitou Tract, Experimental Forest, National Taiwan University. In the study, three plots (A, B, C) were setup, depended on the distance to debris flows, to sample trees based on three different damage levels. Nondestructive test method was also applied on the evaluation of wood properties in July and August, 2003 and the component and yield of the essential oil of leaves were analyzed to understand the influences of debris flow.
Results shown that average DBH of three plots varied as A＞B＞C, however, both their transversal and longitudinal ultrasonic wave velocities (Vt and V(subscript L)) at the DBH position were C＞B＞A and both the transversal and longitudinal velocities of C plots is significantly different from those of A and B plots. The greater distance to the boundary of debris flow, the larger DBH and the lower ultrasonic wave velocity were found. With respect to difference among upper, middle, and lower area of plots along the debris flow, the longitudinal velocities for trees were significantly influenced in the upper area than those from middle and lower area of the A plot. The narrow ring width was occurred in the A plot in 2001, as in B and C plots. However, it continued in both B and C plots in the next year.
Results also shown that the yields of essential oils from the leaves of Taiwania in the A, B, and C plots were 0.10%, 0.16%, and 0.18%, respectively. In addition, the major content of three essential oil were identified as δ-cadinene by using GC-MS, and its relative content was 20.31%, 25.39%, and 28.49%, respectively. These results revealed that both the yields of essential oil and relative content of their major constituent were significantly influenced by the debris flows.

並列關鍵字

Taiwania cryptomerioides ； Debris flows ； DBH ； Tree rings ； GC-MS ； Ultrasonic wave velocity