北京东灵山地区植物群落多样性研究Ⅷ.群落组成随海拔梯度的变化

STUDIES ON PLANT COMMUNITY DIVERSITY IN DONGLING MOUNTAIN,BEIJING,CHINA Ⅷ VARIATION OF COMPOSITION ALONG ELEVATIONAL GRADIENT

以样带法研究了北京东灵山地区落叶阔叶林物种组成随海拔梯度表现出的变化格局。通过变换分割样带的尺度，考察了环境的局部变化对群落主要组成物种的分布及其优势程度的影响。东灵山落叶阔叶林优势种辽东栎和五角枫几乎遍布整个样带，其它伴生乔木树种表现出明显的分布替代格局。以占据率和单种率考察了尺度对群落特征分析的影响。本区落叶阔叶林１ｍ样带最佳分割尺度为：乔木层４０ｍ，更新层８０ｍ、灌木层２０ｍ。样带法在研究植物群落随环境梯度变化格局中具有重要价值。

The distribution pattern of species composition along elevational gradient in deciduous broad leaved forest in Dongling Mountain,Beijing was sampled with transect and analysed in this paper.The dominant species Quercus liaotungensis and Acer mono were distributed nearly over the whole transect and the companion trees and most of shrubs were found in certain fragments respectively.The occupation percentage and the percentage of plots with single species were used to examine the impact of scale on the analysis of community properties.The suitable lengths of the 1 m transect in deciduous broad leaved forest in this area are proposed to be 40 m,80 m and 20 m for canopy layer,regeneration layer and shrub layer,respectively.