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 th...