采用样地调查方法研究了广东惠州莲花山海拔100～900 m区域木本植物的种类组成，并据此分析了该区域木本植物的种类多样性和生物量沿海拔的变化规律及其相互关系。结果显示：莲花山海拔100～900 m样地中共分布有木本植物54科109属181种（变种），且不同样地的优势种存在一定差异，其中，中海拔样地以高大乔木占优势，海拔700 m以上样地以灌木占优势；木本植物的种类丰富度随海拔升高而降低，在海拔200～700 m样地较高。莲花山海拔100～900 m样地中，木本植物的Shannon-Wiener多样性指数、Simpson多样性指数和生物量随海拔升高均呈“低—高—低”的抛物线型分布模式，且均在海拔400 m样地最大，当海拔大于700 m时均明显降低。莲花山不同样地的木本植物中Ⅰ（1.00 cm≤DBH≤5.00 cm）级个体数量均最多，其中，低海拔和高海拔样地的木本植物主要以小径级个体为主，中海拔样地的木本植物主要以大径级个体为主。相关性分析结果表明：莲花山木本植物的科数与海拔极显著（P＜0.01）负相关，属数和种数与海拔均显著（P＜0.05）负相关；木本植物的Shannon-Wiener多样性指数、Simpson多样性指数和生物量与海拔均显著相关，Shannon-Wiener多样性指数和Simpson多样性指数与生物量均极显著相关；Ⅳ（DBH＞20.00 cm）级木本植物的个体数量与生物量显著相关，但Ⅰ、Ⅱ（5.00 cm＜DBH≤10.00 cm）和Ⅲ（10.00 cm＜DBH≤20.00 cm）级木本植物的个体数量与生物量均不显著相关。综合分析结果表明：海拔对莲花山木本植物的种类组成、种类多样性、生物量和径级结构有明显影响，种类多样性越高则生物量越大，且生物量主要受大径级个体数量的影响；推测莲花山不同海拔区域的水热条件差异可能是其木本植物的种类多样性及生物量变化的主要原因。

Species composition of woody plant at altitude of 100-900 m of Lianhua Mountain in Huizhou of Guangdong Province was studied by using plot survey method， and based on this result， the variation rule of species diversity and biomass of woody plant along altitude in this area and their correlations were analyzed. The results show that there are 181 species （varieties） of woody plant belonging to 109 genera in 54 families in plots at altitude of 100-900 m of Lianhua Mountain， and there are some differences in dominant species in different plots， in which， high arbor is the dominant species in plots at midaltitude， but shrub is the dominant species in plots at altitude higher than 700 m； species richness of woody plant decreases with increasing of altitude， and is relatively high in plots at altitude of 200-700 m. In plots at altitude of 100-900 m of Lianhua Mountain， Shannon-Wiener diversity index， Simpson diversity index， and biomass of woody plant show a paracurve distribution mode of “low-high-low” with increasing of altitude， and are the highest in plot at altitude of 400 m， but obviously decrease at altitude higher than 700 m. Individual number of woody plant in class Ⅰ （1.00 cm≤DBH≤5.00 cm） in different plots of Lianhua Mountain are the most， in which， small diameter class individuals are dominant in plots at low and high altitudes， while big diameter class individuals are dominant in plots at mid-altitude. The correlation analysis result shows that family number of woody plant in Lianhua Mountain shows an extremely significantly （P＜0.01） negative correlation with altitude， while numbers of genus and species both show significantly （P＜0.05） negative correlations with altitude； Shannon-Wiener diversity index， Simpson diversity index and biomass of woody plant show significantly correlations with altitude， and Shannon-Wiener diversity index and Simpson diversity index both show extremely significantly correlations with biomass； individual number of woody plant in class Ⅳ （DBH＞20.00 cm） shows a significantly correlation with biomass， but that in class Ⅰ，Ⅱ （5.00 cm＜DBH≤10.00 cm） and Ⅲ （10.00 cm＜DBH≤20.00 cm） has no correlation with biomass. The comprehensive analysis result shows that altitude has evident effect on species composition， species diversity， biomass， and diameter class structure， and species diversity higher， biomass larger， meanwhile， biomass is mainly affected by individual number in big diameter class. It is inferred that difference in water and heat condition of different altitude areas might be the major reason causing change of species diversity and biomass of woody plant.