樹木的耐陰性

Shade Tolerance of Trees

胡元瑋(Yuan-Wei Hu) ； 陳燕章(Yen-Chang Chen) ； 曾彥學(Yen-Hsueh Tseng)

《中華林學季刊》 48卷1期 (2015/03) Pp. 97-112

摘要

在極盛相的老熟森林中，冠層孔隙往往是維持林木更新及樹種歧異度的最重要因子。孔隙的形成會造成光條件在時間和空間上的異質性，也會造成光的可利用性之變化，而樹種會依其生理特性配合孔隙大小之光梯度，以不同的生長策略進入冠層，使森林中產生許多不同演替序列之小區塊及生態地位之分化。因此，樹木的耐陰性在微環境不斷變化的過程中，扮演了很重要的角色。本文將就耐陰性的定義、測量方法及影響耐陰性的原因加以說明，並介紹不同樹種之耐陰性分類，以解釋其對森林動態的影響，最後彙整並比較有關耐陰性的各種假說。

關鍵字

耐陰性 ； 孔隙 ； 森林動態 ； 假說 ； 互償作用

並列摘要

In climactic and mature forests, canopy gaps usually are the most important factors for maintaining the regeneration and diversity of trees. The forming of gaps will produce the temporal and spatial heterogeneity of light condition, and the variability of light utility. Trees would accord the light gradient of different size of gaps by their physiological traits and take different strategies to grow into the canopy, which lead to many small patches of different sere and the differentiation of niches. Thus, shade tolerance of trees plays an important role in the duration of continuous microenvironmental change. This article interpreted the definition of shade tolerance, the methods of its measurement and the factors which might affect shade tolerance. Trees of different shade tolerance sorts were introduced to illustrate their influence on forest dynamics. Different hypotheses of shade tolerance were compiled and compared finally.

並列關鍵字

Shade tolerance ； Gap ； Forest dynamics ； Hypothesis ； Trade-off process