河南省自然林草本层植物群落β多样性及其影响因素

β-diversity of the herbaceous layer plant communities in natural forests and its influencing factors in Henan Province

关键词:  β多样性, 物种周转, 物种嵌套, 空间距离, 自然林草本层, 河南省

Key words:  β-diversity, species turnover, species nestedness, spatial distance, herbaceous layer of natural forest, Henan Province

摘要:

对反映不同群落间物种组成的时空差异或变化的β多样性及其组分开展研究,有助于提高对群落结构及其维持机制的理解和认识。森林草本层是森林群落和森林生态系统的重要组成部分,尽管对林下草本层植物群落β多样性已有一些相关研究,但关于β多样性的组分(如物种周转和嵌套组分)的相对比例、影响因素及其影响程度等方面仍缺乏统一认识。该研究基于河南省168个自然林样地草本层植物群落调查数据资料,通过Jaccard相异性指数、方差分解等方法分析河南省自然林草本层植物群落β多样性格局,并量化空间距离、环境因素和物种丰富度等影响因素对其β多样性的相对贡献。结果表明:(1)自然林草本层植物群落总β多样性的Jaccard相异性指数为0.94,主要来源于物种周转组分(占总β多样性的96.8%)。(2)自然林草本层植物群落总β多样性及物种周转组分随空间距离增加呈显著增加趋势,而嵌套组分随空间距离增加呈显著减少趋势。(3)Mantel检验显示空间距离、环境因素和物种丰富度对自然林草本层植物群落总β多样性均具有显著影响,其中环境因素影响最大,空间距离影响次之,物种丰富度影响最小; 方差分解结果进一步显示空间距离、环境因素和物种丰富度共分别解释了总β多样性及其周转组分27.14%、20.35%的变异,其中环境因素可以单独解释的变异最多(分别占总β多样性的10.62%和周转组分的9.35%)。该研究有助于增强对自然林草本层植物组成变化规律及其影响因素的认识,进而为森林植被保护管理和生态修复提供坚实的科学基础。

Abstract:

Conducting research on β-diversity(beta diversity)and its components, which reflect spatial or temporal variations in species composition among communities, helps to improve the understanding and knowledge of community structure and its maintenance mechanisms. The herbaceous layer of forest is an important part of forest community and forest ecosystem. Although some studies have been conducted on β-diversity of the understory herbaceous plant communities, there is still a lack of consensus on the proportion of β-diversity components such as turnover and nestedness components, as well as the influencing factors and the extent of their impact on β-diversity. This study was based on the survey data of herbaceous layer plant communities from 168 natural forest plots in Henan Province. It analyzed the β-diversity patterns of herbaceous layer in natural forests in Henan Province using Jaccard dissimilarity index, variance partitioning and other methods, and quantified the relative contributions of influencing factors such as spatial distance, environmental factor, and species richness to its β-diversity. The results were as follows:(1)The total β-diversity(as measured by the Jaccard dissimilarity index)of the herbaceous layer plant communities in natural forests was 0.94, which was mainly derived from the species turnover component(accounting for 96.8% of the total β-diversity).(2)The total β-diversity and its species turnover component of plant communities in the herbaceous layer of natural forests showed a significant increasing trend with increasing spatial distance, while the nestedness component showed a significant decreasing trend with increasing spatial distance.(3)Mantel test showed that spatial distance, environmental factor, and species richness had significant effects on the total β-diversity of plant communities in the herbaceous layer of natural forests, with environmental factor, spatial distance, and species richness having the greatest, second, and least effect, respectively; variance partitioning results further showed that spatial distance, environmental factor, and species richness accounting for 27.14% and 20.35% of the variation in total β-diversity and its turnover component, respectively, with environmental factor alone accounting for the most variation(10.62% of total β-diversity and 9.35% of turnover component). This study helps to enhance the understanding of the variation rules of plant composition in the herbaceous layers of natural forests and its influencing factors, thereby providing a solid scientific basis for the protection and management of forest vegetation and ecological restoration.