林冠是森林与外部环境相互作用最直接与最活跃的界面层，影响着森林的物理环境和生物环境。采用半球面摄影技术（Hemispherical Photography）、典范对应分析（Canonical Correspondence Analysis, CCA）和Kruskal-Wallis分析定量研究了森林群落冠层结构与立木分布及多度的关系。结果表明：（1）基于10000 m2调查样地，南岭山地森林群落共有立木47科81属143种，枯立木多来源于林冠上层大树；（2）CCA排序结果显示，冠层结构各参数与立木分布均有一定相关性，叶面积指数、林冠开度与立木分布的关系尤为密切；（3）立木多度与活立木多度在林下散射光分组变量间差异显著（P＜0.05），枯立木多度在林冠开度分组变量间的差异性显著（P＜0.05），立木多度随林下直射光增强而减少。叶面积指数和林冠开度通过影响林下光照条件进而影响立木，尤其是枯立木的形成和多度。%Canopy is the most direct and active interface layer between forest and external environment, which affects physical and biotic environment of forest. By using Hemispherical Photography, Canonical Correspondence Analysis (CCA) and Kruskal-Wallis methods, the relations among the distribution and abundance of standing trees and forest canopy structure were quantitatively studied. The results indicated that (1) There were 47 families, 81 genera and 143 species based on the 10 000 m2 sampling investigations and most of the dead standing trees derived from over-story big old-aged trees;(2) the results of CCA ordination indicated that all of the canopy structure parameters had a certain correlation with distribution of standing trees, and the leaf area index (LAI) and canopy openness (CO) had a significant correlation with distribution of standing trees;(3) The abundance of standing trees and abundance of living standing trees had a significant difference among Transmitted Diffused Light (TDif) groups (P<0.05) and abundance of snags had a significant difference among canopy openness groups (P <0.05), besides, the abundance of standing trees decreased with the enhancement of Transmitted Direct Light (TDir). Moreover, LAI and CO affected under-story light conditions, thereby to the stumpage, especially the formation and abundance degrees of the withered tree.
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