【摘要】 长白落叶松-白桦林是由云冷杉林遭到破坏后形成的次生林,为了更好地了解其物种组成和群落结构,于2015年8月在长白山东北坡按照CTFS标准建立了面积为1 hm~2(100 m×100 m)的长期监测样地,对样地内所有DBH≥1 cm的木本植物进行挂牌、定位、调查,并应用双相关函数g(r)分析了样地内长白落叶松和白桦2个优势树种不同等级的空间分布。结果表明:该样地共调查到活立木个体1 499株,隶属于9科16属22种,大都属于北温带植物区系类型;样地优势种明显,长白落叶松和白桦是样地的优势种,重要值分别为36.08%和24.75%。样地内物种Margalef丰富度指数R、Shannon-Wiener指数H’、Simpson指数D和Pielou指数Jsw分别为2.87、1.71、0.62和0.56。样地内林下更新良好,所有个体的径级结构呈倒"J"型,8个主要树种的径级结构存在差异,长白落叶松呈倒"J"型,白桦和山杨呈近似正态分布,其余5种(包括花楸、毛山楂、红松、稠李和臭松)呈"L"型。样地内所有物种个体的空间格局呈聚集分布,8个主要树种的空间分布都表现出不同程度的聚集。g(r)函数分析表明,2个优势种空间分布随径级和尺度变化表现出不同的格局类型,长白落叶松随径级增大聚集程度逐渐降低;与小径木和大径木相比,白桦中径木具有更强的聚集程度。更多还原

【Abstract】 The larch-birch forest is a secondary forest formed after the spruce-fir forest is destroyed. In order to understand its species composition and community structure,we established a 1-ha( 100 m × 100 m)permanent plot in the northeastern slope of the Changbai Mountains according to CTFS in August,2015.All trees with diameter at breast height( DBH) ≥1 cm were tagged,investigated and mapped. And then we applied the pair-correlation g( r) function to determine the spatial distribution of two dominant species with different rank-classes. The results showed that there were 1 499 individuals belonging to 9 families,16 genera and 22 species in this plot,mostly consisting of the north temperate flora species. Larix olgensis and Betula platyphylla were the major dominant species whose importance values were 36. 08%and 24. 75%,respectively. The Margalef species richness index( R),Shannon-Wiener index( H’),Simpson index( D) and Pielou index( Jsw) of this plot were 2. 87,1. 71,0. 62 and 0. 56,respectively.This forest was in good condition of regeneration and showed a reversed J-shape form in tree size distribution of all individuals. The size structure of eight major species was different. L. olgensis showed an inverted J-shape form, B. platyphylla and Populus davidiana showed an approximately normaldistribution, while the others including Sorbus pohuashanensis, Crataegus maximowiczii, Pinus koraiensis,Prunus padus and Abies nephrolepis all showed L-shape form. The spatial distribution pattern of all individuals was aggregated,and the eight major species also showed aggregation patterns to different extent in this plot. The result of g( r) function analysis showed that the two dominant species with varying rank-classes and distances showed different distribution patterns. The aggregation intensity decreased with the increasing rank class of L. olgensis,while the medium trees of B. platyphylla had more aggregation intensity than small trees and large trees.更多还原