浙江省主要亚热带森林群落类型物种和谱系水平的α和β多样性比较

了解不同森林群落类型的物种和谱系水平的α和β多样性, 有助于指导森林经营和生物多样性保护。本研究比较了浙江省内不同地点主要森林类型(包括常绿阔叶林、常绿落叶阔叶混交林、落叶阔叶林和针阔叶混交林)的物种α多样性和谱系α多样性, 以及物种β多样性和谱系β多样性。研究表明, 该地区主要森林类型的物种和谱系α多样性均存在较大差异, 但控制了空间和地形因子的作用后, 差异几乎全部消失; 森林类型内部及相互间的物种和谱系β多样性均存在显著差异, 同种森林类型内部的物种和谱系β多样性分别小于不同森林类型之间的物种和谱系β多样性, 且在控制了空间和地形因子的作用后, 以上差异仍然显著。本研究表明影响亚热带主要森林群落类型物种和谱系水平的α和β多样性的因素存在差异: α多样性可能主要受到空间和地形因子等的影响, 而β多样性则可能受到森林类型的重要影响。

Taxonomic and phylogenetic α and β diversities of major subtropical forest community types in Zhejiang Province

Knowledge of taxonomic and phylogenetic α and β diversities of different forest types is critical to improving our understanding of forests and their structure, which can guide forest management and biodiversity conservation. In this study, we investigated the taxonomic and phylogenetic α (Shannon-Wiener index and PSV (phylogenetic species variability) diversity, respectively) and β (Chao’s index and PCDp (phylogenetic community dissimilarity among nonshared species) diversity, respectively) diversities of four main forest types, including evergreen broad-leaved forest (EBLF), evergreen and deciduous broad-leaved mixed forest (EDBLF), deciduous broad-leaved forest (DBLF), and coniferous and broad-leaved mixed forest (CBLF) in Zhejiang Province. α diversity represents biodiversity within a single forest plot; β diversity is divided into two levels. One is the β diversity between forest plots within a single forest type (intra-forest type β diversity), and the other the β diversity between forest plots from different forest types (inter-forest type β diversity). We found that the taxonomic and phylogenetic α diversities differed among forest types. However, when the geographical and topographical variables were taken into account, these differences largely disappeared. We also found the intra- and inter-forest type β diversities greatly differed, and the overall intra-forest type β diversity was lower than inter-forest type β diversity, regardless of whether geographical and topographical variables were controlled. These results suggest the controlling factors of taxonomic and phylogenetic α and β diversities differ in the studied subtropical forest types. Geographical and topographical variables may play critical roles in influencing forest taxonomic and phylogenetic α diversities, whereas forest type is largely responsible for forest taxonomic and phylogenetic β diversities.