小兴安岭谷地云冷杉林林隙形成木特征及植物多样性

Characteristics of Gap Makers and Plant Diversity in Picea asperata and Abies fabri Forest in Xiaoxing'an Mountains

2013年6~8月,在小兴安岭凉水国家级自然保护区云冷杉林1.5 hm A2的固定标准地内,调查了所有林隙形成木的树种、基径、胸径、树高、折断高度、形成方式、腐烂等级以及草本植物、灌木的种类、多度、高度、盖度,并计算了它们的丰富度和重要值。结果表明：掘根倒木为36株,干中折断和干基折断倒木分别为17株和6株。就Shannon多样性指数（H）、物种均匀度指数（J）、Simpson生态优势度指数（D）而言,均为掘根样地〉干中折断样地〉干基折断样地。在掘根和折干样方内,东北羊角芹的重要值均最大,分别为14.2、13.2。掘根样方内的优势种为水金凤和荨麻,折干样方内的优势种为乌头。在相同倒木腐烂等级条件下,掘根样方的物种丰富度均大于折干样方。干基折断和干中折断草本层植物的丰富度在东、南、西、北样方内均小于对照样方的,而掘根样方内却相反。

An investigation was conducted in a 1. 5 hm2 permanent standard plot of Picea asperata and Abies fabri forest to determine the species,basal diameter,DBH,height,breakage height,formation mode,decayed level of all gap makers,the species,abundance,height,cover of all herbs and shrubs,and calculate their important value and richness in June August,2013. The number of uprooted trees was 36,the number of stem breakage and base breakage was 17 and 6,respectively. The value of Pielou evenness index（ J）,Simpson ecodominance index（ D）,Shannon index（ H） were listed in the order of all uprooted tree 〉stem breakage〉base breakage. Within the plots of uprooted tree and breakage,the important value of Aegopodium alpestre was the biggest,14. 2 and 13. 2,respectively. The dominant species in the plots of uprooted trees are Impatiens nolitangere and Urtica fissa,but Aconitum carmichaeli in the plots of breakage. Under the same decayed level of tree falls,species richness in the plots of uprooted trees was more than that in the plots of breakage. The herbs＇ richness in the east,south,west,north plots of base breakage and stem breakage were smaller than that in the control,but opposite in uprooted tree plots.