南仁山亞熱帶雨林小苗不同生育地存活、生長研究

Abstract

墾丁國家公園南仁山保護區內，因受地形及氣候共同作用而擁有四種不同生育地，即強迎風區、緩迎風區、背風區及溪穀區，今選擇強迎風區、緩迎風區及背風區，加上林隙區共四種生育地，分別種下紅花八角、?春石斑木、江某及白匏子四種當年生之小苗，以瞭解其在不同生育地彼此間之存活、生長表現的差異。 存活率表現以紅花八角和?春石斑木最佳，可達80％以上，而以白匏子最低，多在40％以下，江某則介兩者之間，經存活率檢定，發現除白匏子在生育地間統計上的意義外，其餘各種在各生育地間並無顯著差異，明白顯示林隙種類之白匏子具有林隙更新的特性。在生長檢定上，各樹種在林隙區與其他各生育地間差異亦極為顯著，而在其他各生育地間生長差異表現則不顯著。 南仁山區多樣性的生育地，提供大量小苗生長的空間，而小苗生長受季節性變化影響甚大，主要生長季大致從3月至9月之間。由實驗結果看來，小苗生長在森林內主要生育地間之存活率及生長表現均不甚顯著，同時區內各分佈類型之代表樹種與生育地間關係亦不明確。可見南仁山區植物社會形成原因，仍有待進一步對種子的產生、散播、及小苗的長期觀測中得以瞭解一二。

Four major habitats of the Nanjenshan Preserve, based on climatic and topographic interactions, include the following: windward I, windward II, leeward, and creek type. Differences in survivorship and growth rate of the seedlings between these habitats were tested by growing about 2 month seedlings of four representative species within each habitat. Both Illicium arborescens and Rhaphiolepis indica var. hiiranensis showed a high survival rate (over 80%, except in windward), and Mallotus paniculatus represents the lowest (under 40%, except in gap); The survival rate of Schefflera octophylla was found to be variable, although all measurements were higher than 50%. Only Mallotus paniculatus revealed significant differences between habitats in survival analyse. The results of ANOVA indicated that growth rate was hightest for all species within the gap area than those of the other habitats. Differences in the growth of the seedlings was also observed in strong response to seasonal changes. Beside gap site, there was no singnificant difference in survival rate and growth between habitats under the forest. This was probablily due to a short period of experiment. A longer period observation of study and more information about seed production and seed dispersal were needed to explain the segregation patterns of the vegetation.