墾丁高位珊瑚礁森林位於墾丁高位珊瑚礁自然保留區。該地區主要是板塊擠壓效應下隆起的高位珊瑚礁岩塊，經長期演替所形成的高位珊瑚礁原始林。本研究想藉由永久樣區的設置標準化方法進行樣區標定，木本植物胸高直徑≧1 cm及小苗普查調查，瞭解墾丁高位珊瑚礁森林的組成、族群結構及更新情況，做為未來追蹤森林動態的基礎資料。 至1997年止，已完成3.25公頃的樣區標定，調查所有胸高直徑≧1 cm的木本植物，給予鋁牌號碼，紀錄植物種類、胸高直徑大小、分布位置。此外，在每個5*5 m2樣區內選取1m2的小樣區，調查區內DBH<1 cm的小苗種類、數量、小苗高度、紀錄樹冠高度，以瞭解這座森林內小苗的組成。以3.25公頃面積大小分析胸高直徑≧1 cm的木本植物初步統計結果，共記錄80種樹種、13104棵植株。森林組成的結果顯示，最優勢植物是黃心柿，在科的層級方面，大戟科所佔的種數最多。從種的豐富度排序來看，除了黃心柿佔有相當的優勢外，並由少數幾種樹種取得優勢，其他樹種的優勢度逐漸減少。另外，從種的個體累積百分比結果得知，黃心柿的株數（7059株）佔所有株數的53.87%。此外，累計株數排名的前12種樹種，則佔了總株數的89.65%，其餘68種樹種組成10%的株數，由此可見此森林內各樹種的植株數目分佈相當不平均，大部分個體是由少數幾種優勢樹種組成。 在植物的徑級分佈方面，並沒有顯示何種更新功能群有出現特定徑級結構的趨勢。此外，有一些樹種，尤其是J形徑級分布的樹種，其在森林內的更新是有困難的。這些天然更新困難的樹種大部分是不耐陰性的陽性樹種。 小苗的調查結果共紀錄52種，只佔3.25公頃普查樹種種類的65%，似可歸因於樹種的族群數量太少或者是這些樹種的更新率低。此外，除黃心柿外，優勢樹種的小苗並沒有比稀有樹種佔有優勢。這個結果支持這座森林是處於非平衡狀態。從小苗的分佈資料也指出孔隙的出現，並沒有影響樹種種數及豐富度的分布。亦即在森林社會更新上，孔隙的出現並未造成重大影響。大部分樹種的小苗在未達30 cm時即死亡，這種情形不因樹種優勢度而改變。此項事實指出影響森林更新的因子可能在植物生活史初期就已決定。 Kenting high coral reef forest is located at the Kenting High Coral Reef Nature Preserve on the Heng-Chun Peninsula at southern Taiwan. This forest is particular noteworthy because its soil is derived from uplifted coral reef. The soil is very shallow and alkline, thus provide an excellent opportunity to study the adaptive significance of trees as well as the interactions of abiotic (e.g. soil nutrient gradient) and biotic factors (e.g. competition, seed dispersal agents) on the structure and dynamics of this forest. A 3.25 ha permanent plot was established in 1997 to study the structure and floristic composition of this forest. All woody plants 31 cm DBH were tagged, measured, mapped, and identified to species. In addition, in each 5 x 5 m2 quadrat, we established a 1 x 1 m2 subquadrat to study the seedlings composition of this forest. A total of 13104 individuals of 80 species were found in the plot. The most common species was Diospyros maritima Blume (Ebenaceae). The family with the largest number of species was Euphorbiaceae. There is no significant difference between different regeneration guilds for the trend of stem diameter distribution. Some species have difficulties regenerate in this forest, especially species showed J-shape size distribution. These species which have difficulties regenerate in this forest are shade-intolerant species. Only 65% of species were found in the seedlings survey, this may be due to small sample size or low recruitment rate of these species. In addition, common species do not necessarily have an advantage over rare species in terms of number of seedlings. This fact supports that this forest is at an non-equilibrium stage. Our seedling data also indicated that species richness and abundance did not affect by the presence of gaps. This suggests that gaps may not play an important role in the regeneration of Kenting high coral reef forest. Furthermore, our seedlings data showed that in most species, common species and rare species alike, their seedlings died before they reached 30 cm in height. This fact strongly suggested that some forces which affect forest dynamics operate much earlier life cycle.
