中文摘要：

对滇石栎分布区的南部边缘到北部边缘的8个种群进行取样，分析叶片的比叶重、叶密度、低温敏感度和Fv／Fm 4个功能性状的变异及其相关性，主要探讨叶片功能性状的种内变化程度，种群、个体和叶片间的差异对功能性状变异的相对贡献，以及种群叶片功能性状变化与生境纬度和气温的关系。研究结果显示．4个功能性状的种内变异系数分别为16.0％、17.7％、21．1％和4．01％。种内的变异源来自种群、个体和叶片间的差异，其中种群间和叶片间的差异贡献最大。生境气温与比叶重和Fv／Fm分别有显著的负相关和正相关关系，与叶密度和低温敏感度分别呈开口向下和开口向上的抛物线变化。在4个性状的主成份分析显示，没有一个种群更靠近第1和第2主成份的原点，分布区边缘种群位于第一轴的两侧。研究结果表明．物种在分布区内为适应环境变化叶片功能性状产生变化，没有一个种群可代表物种水平上的叶片功能性状数量特征。在研究植物种功能性状的平均值或进行功能性状的种问比较时，种内变异不能被忽视。

英文摘要：

We quantified intraspecific variation and covariation of leaf mass per area （ LMA）, leaf dry matter con- centration （ LD）, leaf frost sensitivity （LFS） and Fv/Fm of leaves of 8 Lithocarpus dealbatus populations across the geographical distribution from north to south to determine the magnitude and whether it is related to environmental conditions, latitude and mean annual temperature. The results showed that the total variation （coefficient of varia- tion） of LMA, LD, LFS and Fv/Fm were 16. 0%, 17.7%, 21.1% and 4. 01% respectively. The total intraspecific variation was contributed by the difference among populations, individuals and leaves. The difference among popula- tions accounted for the largest total variation in LMA, LD and Fv/Fm, whereas the difference among leaves accoun- ted for the largest total variation in LFS. On population level, LMA was significantly positive related to the latitude and Fv/Fm was significantly negative, but LD and LFS were not related to the latitude. LMA decreased while Fv/Fm increased significantly with the increase of mean annual temperature. LD was a downward quadratic variation, and LFS was upward with the increase of mean annual temperature. The principal component analysis of four functional traits showed that no population was located nearer to the origin of the first and second principal component, and populations at the edge of distribution area located at both sides of the first principal component axis. The results sug- gested that the environmental variation in the distribution could cause intraspecific variation of functional traits. There is no population could represent a species in functional traits. When an average trait value for species is considered and trait comparisons are done among species, intraspecific variation of traits could not be ignored.