頁籤選單縮合
題名 | 修枝對臺灣杉幼林生長及節癒合之效應 |
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作者 | 羅卓振南; 鍾旭和; 陳燕章; | 書刊名 | 林業試驗所研究報告季刊 |
卷期 | 3:4 1988.12[民77.12] |
頁次 | 頁241-253 |
分類號 | 436.257 |
關鍵詞 | 幼林; 生長; 修枝; 節癒合; 臺灣杉; |
語文 | 中文(Chinese) |
中文摘要 | 本研究之目的,在探討台灣杉幼齡林適宜之修枝年齡,修枝高度,以 及觀察修枝傷口之癒合趨勢,以期生產無節大徑木,提高木材品質及經濟價植。 供試林分為本所六龜分所試驗林第3林區之9年生台灣杉人工林,初次修枝每公 頃暫定為1000株,修枝高度係以林木樹高為標準,將修枝高度定為樹高之 (A)1/4;(B)1/3;(C)1/2;及(D)完全不做修枝處理等四種。本試驗施行於民國71 年2月間,迄民國76年2月間調查修枝後5年之效應,結果要述如次: 1.9年生台灣杉幼林若行修枝,對林木之胸徑、樹高及材積生長均無顯著之影響, 即使修枝高度達樹高之1/2時亦然。 2.本試驗探討之幼齡林,側枝節徑分佈位於0.2∼2.5cm之間,修枝傷口於3年內 均已癒合,修枝確能提高林木之品質生長。 3.枝條節徑級(ND)、(cm)與修枝傷口癒合時間(Y)、(月)之最適關係式為: Y=12.40+3.2857ND+2.6786ND^2,呈二次曲線上升,即節徑愈大,傷口之癒合能 力愈差,需較久時間始能癒合。節徑位於1.6cm以下者,修枝傷口在2年內即可 癒合。採用上式推算各節徑修枝傷口之癒合時間,若能配合林分之側枝發育狀 況,即可釐定最適之修枝林齡。 4.癒合節之觀察結果顯示,節徑在0.6∼1.7cm者,在修枝後第4年左右,年輪生 長即趨於平滑,恢復正常生長,年輪寬度仍呈均勻。 5.未作修枝之林分,冠層下方之部份側枝約在10年生時即漸乾枯,然至15 年生 時仍殘存而不自動脫落,致成死節,顯示台灣杉造林木實施人工修枝確實必要。 6.適宜之修枝高度必須配合林分之生長結構及生長速率,修枝林齡若欲提早,其 強度應較保守,若於9年生修枝,則其強度可達至樹高之1/2處。 7.9年生台灣杉經修枝後5年,對樹幹完滿程度無顯著之影響。 |
英文摘要 | The purposes of this study are to search for the best tree age for pruning and the best pruning height and to understand the occlusion tendency of branches after pruning. The 9-year-old Taiwania (Taiwania cryptomerioides Hayata) plantations in Lu-Kuei Experimental Forest of Taiwan Forestry Research Institute were treated by (A)pruning up to 1/4 tree height, (B)pruning up to 1/3 tree height, (C)pruning up to 1/2 tree height, and (D)no pruning. The trees were pruned in Feb. 1982 and the results were recorded in Feb. 1987 and analyzed as follows: 1.pruning had no significant influences on the growth of DBH, height, and volume of 9-year-old Taiwania plantations, even the pruning height was up to 1/2 tree height. 2.The branches of 0.2-2.5cm in diameter were occluded within 3 years after pruning, and hence to improve the timber quality. 3.The relationship of the time needed for occlusion (Y) and branch diameter (ND) could be expressed as the equation:Y=12.40+3.2857ND+2.6786ND^2. 4.The branches of 0.6-1.7cm in diameter were occluded and the growth rings were smooth again within 4 years after pruning, and hence the timber quality was improved. 5.The branches of trees without pruning would die when the trees were 10-year-old and not drop off enen until 15-year-old and hence dead knots were made. 6.Pruning height should be made compromise with tree age. This study showed that pruning height of 9-year-old Taiwania plantation could be up to 1/2 tree height. 7.The tree form quotients of Tawiania were 0.96% and 0.67% in 9- and 14-year-old, respectively. This showed that pruning had no significant influences on tree forms. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。