中文摘要：

掌叶木（Handeliodendron bodinieri）是国家一级保护植物,中国特有的珍稀濒危单种属植物之一。对广西乐业县神木天坑和穿天洞坑的掌叶木种群展开调查,结果表明：两样地掌叶木种群空间分布格局均为随机分布;径级结构和高度级结构显示Ⅰ和Ⅴ年龄级的幼苗和老木数量稀少,而大量个体集中在Ⅱ、Ⅲ、Ⅳ年龄级,呈现纺锤形结构,即为衰退型种群;种群动态指数Vpi为0.592、Vpi′为0.118,即种群属于增长型,但易受外部环境因素干扰,增长趋势极小,从长远来看,由于Ⅰ级幼苗的缺失,最终会导致种群的衰退。静态生命表和存活曲线显示掌叶木种群随着年龄增长,生存质量越来越低,存活曲线更趋于DeeveyⅡ型,属于衰退型种群;针对该种群的特征和濒危原因,探讨其保护策略。

英文摘要：

Handeliodendron bodinieri is an endangered endemic single species genus plant and has been listed as first degree national protective plant. This study investigated the population dynamics of H. bodinieri in Shenmu Tiankeng and Chuandong Tiankeng of Leye County. The results showed that both two populations had random distribution. It took the spindly shape based on the structure of diameter and height classes,indicating the declining population. The population dynamic trend was studied with Chen Xiaode quantitative methods. The population had growth trend,but the growth was very limited considering the external random disturbance. However,the population would decline after a long period for lack of Ⅰ and age classes. Individual mortality rate of population gradually rose with age increasing. The survival rate was well fitting the Deevey-II curve,indicating the declining population. Some protection strategies were put forword aiming at the population dynamics and endangering reasons.