恆春半島高士佛常綠闊葉林之短期林分動態

Short-Term Stand Dynamics of an Evergreen Forest in the Kaoshifo Experimental Forest, Southern Taiwan

張勵婉(Li-Wan Chang) ； 王相華(Hsiang-Hua Wang) ； 陳永修(Yung-Hsio Chen) ； 楊國禎(Kuoh-Cheng Yang) ； 簡慶德(Ching-Te Chien) ； 薛惠芳(Hui-Fang Hsueh)

《台灣林業科學》 20卷4期 (2005/12) Pp. 293-302

https://doi.org/10.7075/TJFS.200512.0293

摘要

高士佛試驗林地0.6ha(300×20m)永久樣區設立於1995年，7年後進行樣區內木本植物複查，包括新增、死亡，以及密度、胸高斷面積、徑級結構變化等，進而探討7年來樣區之林分動態變化。樣區於1995年紀錄127種木本植物，在2002年總計有5種植物遷出，2種植物移入，然森林之優勢種類組成無明顯變化。上述7年間樣區新增木本植物974株，平均年新增率為1.98%：死亡988株，平均年死亡率為2.27%；總體密度略為減少（-23株ha^(-1)，-0.20%）。相對的，7年間樣區之胸高斷面積生長量為345平方公尺ha^(-1)，成長率為6.88%，平均年成長率為096%；顯示樣區木本植株之胸徑有逐漸往大徑級移動之現象。從喜光之陽性樹種密度明顯降低，演替中、後期樹種密度增高及總體生物量逐漸累積等現象推測，林分結構在1995至2002年間似乎逐漸朝向老熟林階段推進，然而未來仍有不同擾動因子會影響其動態發展，須藉由長期的觀察及研究資料的累積，以瞭解其動態變化模式。

關鍵字

永久樣區 ； 複查 ； 森林動態 ； 高士佛 ； 恆春半島 ； 台灣

並列摘要

A 0.6-ha permanent transect plot, 300×20 m, was set up at the Kaoshifo Experimental Forest of the Taiwan Forestry Research Institute in 1995, and it was re-inventoried in 2002. All individual trees with a dbh ≧1 cm were mapped and recorded both in 1995 and 2002. The rate of mortality, recruitment, and also the change in composition and structure were analyzed to determine the stand dynamics of this evergreen forest during this 7-yr period.
Among the 127 woody species recorded in 1995, 5 were not seen in 2002. In the same period, 2 new immigrating species were recorded. The dominant species composition didn’t change much during this period. The tree density of 1995 was 11,052 ha^(-1), and had decreased to 11,029 ha^(-1) in 2002; this included 974 new recruits (1.98% yr^(-1)), and 988 dead trees (2.27% yr^(-1)). Only a slight decrease in tree density (0.03% yr^(-1)) in this plot over this period; in contrast, the basal area of the plot increased 3.45 m^2ha^(-1) (0.96% yr^(-1)) during this period; and it was deduced that the average dbh of trees in this plot was getting bigger. Since the density of light-demanding trees significantly decreased, the density of shade-tolerant trees significantly decreased, and the average tree basal area obviously increased in this period; therefore, it seemed that the structure of this evergreen forest was moving toward an old-growth stage between 1995 and 2002. Long-term monitoring is necessary for understanding how forest dynamics proceed, since many disturbance regimes can influence forest dynamics.

並列關鍵字

permanent plot ； re-inventory ； forest dynamics ； Kaoshifo ； Hengchun ； Taiwan