奧萬大楓林區辛樂克颱風後林木生長與存活研究

Ecological Monitoring of Tree Growth and Survival after Typhoon Sinlaku at Maple Tree Zone in Aowanda, Taiwan

曾喜育(Hsy-Yu Tzeng) ； 曾彥學(Yen-Hsueh Tseng) ； 何伊喬(Yi-Chiao Ho) ； 郭礎嘉(Chu-Chia Kuo) ； 邱清安(Ching-An Chiu) ； 呂金誠(King-Cherng Lu)

《林業研究季刊》 33卷4期 (2011/12) Pp. 1-19

https://doi.org/10.29898/SHBQ.201112.0001

摘要

奧萬大楓林區為河床沖積之典型濱岸植群，是臺灣最著名之森林遊樂據點，然於2008年受颱風連續侵襲，遭溪水流浸與土石流掩埋。本研究於2009年1月於楓林區設置90m×230m之長期監測樣區，每季進行樣區之地形量測，及受土石掩埋與洪氾干擾下之各樹種生長與存活調查，期能瞭解洪氾干擾下之林木演替與更新機制，以及提供低漥地區植生復育技術之參考。長期監測樣區共紀錄44科69屬73種植物，地被之蕨類、草本與木本植物之種子苗、稚樹等都遭洪氾沖刷或土石掩埋。地形測量結果顯示，楓林區之河道與地形受降雨、土石流影響而變動。由樣區林木位置圖顯示，樹種組成與分布呈明顯的鑲嵌狀或帶狀分布，喬木層樹種 （胸徑≧ 3cm）之林木共1,201株，以楓香（261株）、台灣櫸（186株）、山肉桂（159株）、青剛櫟 （92株）以及江某（90株）等較為優勢。樣區內林木受洪氾干擾有799株，第1季受害枯死有225株，第2季有97株，第3季有167株，3個季節林木累計枯死率為61.20%。第4季因受莫拉克颱風影響，新增土石掩埋57株林木，第4季林木調查累計枯死率達67.99%。不同季節、不同樹種之存活率均不同，反映其對土石掩埋與洪氾干擾之耐性差異。一年監測結果顯示，主要組成樹種中，僅楓香、九芎的累計枯死率低於20%，反映其對土石衝擊、溪水淹浸有較大的耐受性，此2樹種或可作為經常淹水之低漥地區之植生復育優先選擇樹種。調查發現植物在遭受逆境衝擊後，易因生長勢衰退而遭病蟲害入侵造成二次傷害致死；第3季調查亦發現，楓香樹幹開始遭到蠹蟲為害。奧萬大楓林區的楓香在遭受土石掩埋與衝擊的洪氾干擾下雖大多數植株得以存活，但是否因病蟲害而致死，有待更進一步的後續監測調查。

關鍵字

奧萬大 ； 楓香 ； 濱岸植群 ； 颱風 ； 土石流 ； 生態監測

並列摘要

Maple Tree Zone of Aowanda National Forest Recreation Area is the typical riparian vegetation where has not disrupted by flooding for a long time, is the most famous Taiwanese forest recreation area in maple scenery. However, the maple trees were lashed by flooding and debris flow of a sequence of typhoons, Sinlaku especially, in 2008. We set a 90 m×230 m long-term monitoring sampling plot at Maple Tree Zone. The location and diameter of breath height (DBH) for each species individual tree and the topography of plot were measured. The status of growth and survival for each species after flooding and debris flow were monitored in each season while the topography was measured at the same time. There are 1,201 individuals in sampling plot and Liquidambar formosana (maple tree, 261 trees), Zelkova serrata (186 trees), Cinnamomum insularimontanum (159 trees), Cyclobalanopsis glauca (92 trees), Schefflera octophylla (90 trees) were the dominate species. The location map of each species individual tree (DBH ≧ 3cm) in sampling plot showed mosaic or zonation. Our result showing that the position of streamway and topography of Maple Tree Zone were affected by rainfall. The individuals of fern, herbaceous, and seedlings and saplings of woody plants were destroyed by flooding and debris flow. There were 225, 97 and 167 dead trees were monitored during our survey period, respectively; and total 61.20% individuals were dead. The survival rate showing different between seasons and species reflected the difference of trees sensibility and tolerance after disrupted by flooding and debris flow. Liquidambar formosana got the lowest dead rate somewhat expressed the maple trees might adapt in the riparian zone. However, the survival maple trees attacked by scolytid beetles were recorded in our investigation recently and the following survey on survival monitoring of maple trees attacked by those scolytid beetles were necessary.

並列關鍵字

Aowanda ； Liquidambar formosana ； riparian vegetation ； typhoon ； debris flow ； ecologicalmonitoring