脊线对武夷山针阔混交林群落特征的影响

Effect of Ridge Line on Community Characteristics of Mixed Forest in Wuyi Mountain

摘要

为探究脊线上发育的中山针阔叶林的群落学特征。采用典型样地法对武夷山国家公园进行植被调查，通过统计林下物种组成、多度、物种多样性和生物量，分析脊线物种多样性随面积的变化趋势与两侧坡向生物量的变化趋势得到脊线森林群落的部分特征。结果标明，脊线样地内共有维管植物24科43属67种，其中裸子植物2科2属2种，被子植物21科40属64种，共2 889株。样地最小调查面积为1 500 m²，鹿角杜鹃（R. latoucheae）、细齿叶柃（E. nitida）、箬竹（I. tessellatus）分别是乔木层、灌木层、草本层的优势物种。脊线两坡向物种丰富度指数显著差异，地上生物量大于地下生物量且脊线东南坡生物量大于西北坡生物量。脊线植物形态学特征普遍为个体胸径较小（平均5.55 cm），高度低（平均6.79 m），林分密度（1.45株/m²）较非脊线森林群落大，形成单一冠层，在物种组成和结构上具有独特性，与物种组成相似的中山矮曲林形成鲜明差异。本文首次系统揭示了武夷山脊线森林群落的独特结构特征，填补了脊线地形因子对山地森林生态系统影响机制的研究空白。

Abstract

To investigate the community characteristics of mid-mountain needle-leaved and broad-leaved forests developed along ridge lines, a vegetation survey was conducted in Wuyishan National Park using the typical quadrat method. By statistically analyzing the species composition, abundance, species diversity, and biomass of understory vegetation, the variation trends of species diversity along the ridge line with area and the biomass changes on both slope aspects were examined to reveal partial features of the ridge line forest community. The results indicated that the ridge line quadrats contained a total of 67 vascular plant species from 43 genera and 24 families, including 2 gymnosperm species from 2 genera and 2 families, and 64 angiosperm species from 40 genera and 21 families, totaling 2 889 individuals. The minimum survey area for the quadrats was 1 500 m². The dominant species in the tree layer, shrub layer, and herb layer were Rhododendron latoucheae, Eurya nitida, and Indocalamus tessellatus, respectively. Significant differences were observed in species richness indices between the two slope aspects of the ridge line. Aboveground biomass exceeded belowground biomass, and the biomass on the southeastern slope was greater than that on the northwestern slope. The morphological characteristics of ridge line plants generally included smaller individual diameters at breast height (average 5.55 cm), lower heights (average 6.79 m), and higher stand density (1.45 individuals/m²) compared to non-ridge line forest communities, forming a single canopy layer. These features exhibited uniqueness in species composition and structure, contrasting sharply with mid-mountain dwarf twisted forests of similar species composition.This paper systematically reveals for the first time the unique structural characteristics of forest communities along the Wuyi Mountain ridgeline, filling the research gap on the influence mechanisms of ridgeline topographic factors on mountain forest ecosystems.

Graphical abstract

关键词

森林群落 / 脊线 / 武夷山国家公园 / 物种多样性 / 生物量

Key words

forest community / ridge line / Wuyishan national park / species diversity / biomass

基金资助

福建省教育厅中青年教师教育科研项目（科技类）(JAT210069)