大兴安岭多布库尔国家级自然保护区植物多样性和群落结构特征

天然林植物多样性保护对于其生态服务功能至关重要,大兴安岭是我国重要国有林区,现有国家级自然保护区保护区林分特征及其耦合关系揭示是天然林保护与生态服务综合提升的基础。于2017年8—9月对多布库尔国家级自然保护区的乔、灌、草和更新层个体大小特征、群落特征和植物多样性特征进行详细调查,冗余分析与方差分解分析解析植物多样性和群落结构特征的耦合关系。结果表明:1)多布库尔保护区主要树种为落叶松,相对多度为42%,其次是白桦和黑桦;灌木中榛所占比例最高,达到60%;草本共记录116种,其中莎草科的羊须草所占比例最大,超过10%;更新层主要树种为蒙古栎,相对多度达54%,其次为白桦。2)多布库尔保护区乔木胸径和树高仅相当于1970年代的55%,乔木和草本丰富度较大兴安岭核心地区(呼中保护区)高出50%—60%。3)冗余分析和方差分解分析结果表明林分个体大小特征的独立效应和乔木层特征对多样性变化贡献最大,乔木层树高与植物多样性变化具有最紧密关系。大兴安岭地区森林已经全部纳入国家天然林保护工程,上述国家自然保护区相关数据是当地本底数据(当地森林以幼龄林为主,尚需要更长时间保护),将为进一步保护区政策制...

Characteristics of plant diversity and community structure in Duobukuer Nature Reserve in Daxing'anling area

Biodiversity conservation including plant species in natural forests is very important for their ecosystem service function. Daxing''anling is an important state-owned forest region in China. The characteristics and coupling relationship of the existing national nature reserves are the basis for the comprehensive improvement of natural forest protection and ecological services. In this paper, from August to September of 2017, the individual size characteristics, community characteristics and plant diversity characteristics of arbor, shrub, herb and regeneration layer were investigated in Duobukuer National Nature Reserve. The redundant analysis and variance partitioning analysis were conducted to analyze the coupling association and possible factors responsible for diversity variations. The results showed that:(1) Larix gmelinii is the main tree species in Duobukuer, had a relative abundance of 42%, followed by Betula platyphylla and Betula dahurica. The proportion of hazelnut (Corylus heterophylla) is the highest among shrubs, reaching 60%. A total of 116 species of herb layers were found, of which Carex callitrichos accounted for the largest proportion, exceeding 10%. The main tree species in the regeneration layer was Quercus mongolica (54%), followed by Betula platyphylla. (2) The diameter and height of trees were only 55% of those in 1970s, and the richness of trees and herbs was about 50%-60% higher than that in Huzhong Nature Reserve of the central Daxing''anling. (3) Redundancy analysis and variation partitioning showed that the individual size (rather than community features), and arbor layer characteristics (rather than shrub and herb layer) contributed the most to the plant diversity variation observed in this study. Of all the tested parameters, tree height gave the most significant explaining power for the plant diversity variations. The forests in Daxing''anling Mountain have been fully included in the Natural Forest Protection Program (NFPP, completely inhibited timber harvest since 1999). The above-mentioned data from the National Nature Reserve, as a local background data, clearly showed that the forests in this region were still in their young stage and long-term protection are necessary. These data will provide supports for further national reserve policy making and implementation of the NFPP in northeast China.