长白山白桦林空间结构研究

Stand Spatial Structure of Secondary Birch Forest in Changbaishan Mountain

于2006年在长白山建立了一个面积为5.2 hm2的次生白桦林永久样地,并对样地内的每株树木测量了坐标和胸径.运用混交度、大小比数和角尺度研究了该林分的空间结构.研究表明:该样地的平均混交度值为0.540,平均角尺度值为0.575.次生白桦林总体上处于中度混交水平,先锋树种和针叶树种的混交度高于其他类型的树种;次生演替的先锋树种在生长上处于优势,红松(Pinus koraiensis)、蒙古栎(Quercus mongolica)、水曲柳(Fraxinus mandshurica)等主要树种在该林分中处于劣态个体的比重高于先锋树种,槭属类植物处于劣态;次生白桦林总体上呈聚集分布格局.该林分的空间结构特点与所处的次生演替早期阶段和各个树种在林分中的地位、繁殖方式、更新策略以及采伐干扰等有关.

In 2006,a permanent plot of 5.2 hm2 was established in Changbaishan Mountain,in which all trees were sized by diameter breast height（DBH） and mapped.Its stand spatial structure was studied by means of three indicators,which are mingling,neighborhood comparison and neighborhood pattern.The mean mingling and neighborhood pattern of this plot are 0.540 and 0.575,respectively.The results indicate that the forest is moderate mingling level,and the mingling level of pioneer species and conifers are higher than any other kinds of species;the pioneer species of secondary succession are dominant in growth,while most of Pinus koraiensis,Quercus mongolica and Fraxinus mandshurica trees are in disadvantage,and the maple species are in disadvantage vertically;the forest is aggregated.These characteristics of spatial structure is related with secondary early stage of succession,tree species status in the stand,regeneration mode,reproduction strategy and thinning disturbance.