Study On α And β Diversity Of Species And Pedigree Of Main Subtropical Forest Communities In Zhejiang Province

Knowledge of the taxonomic and phylogenetic α and β diversities patterns of different forest types is beneficial to our understanding of the forests, which could guide forest management and biodiversity conservation. Therefore, we set up 48 30×30 m forest plots distributed in Wuyanling, Baishanzhu, Fengyangshan, Jiulongshan, Gutianshan, Qingliangfeng, Tianmushan and Longwangshan National Nature Reserves in Zhejjiang Province. We conducted community survey in these forest plots according to the census protocols of Forest dynamics plot of Center for Tropical forest Science.We firstly investigated the community structure and composition of the 48 plots. We recorded 37212 stems with DBH (diameter at breast height) ≥1cm, average stem density was 8613 ind./ha. The stems belong to 373 species,160 genera and 66 families. We secondly classified the plots into evergreen broad-leaved forest, evergreen and deciduous broad-leaved forest, deciduous broad-leaved forest, coniferous and broad-leaved forest, according to the relative proportion of the importance value of evergreen broad-leaved species, deciduous broad-leaved forest and coniferous species in the plot. After that, we investigated the taxonomic and phylogenetic a (Shannon-Wiener index and PSV index, respectively) and β (Chao’s index and PCDp index, respectively) diversities of the main forest types (i.e. evergreen broad-leaved forest (EBLF), evergreen and deciduous broad-leaved mixed forest (EDBLF), deciduous broad-leaved forest (DBLF), coniferous and broad-leaved mixed forest (CBLF)). Specifically, a diversity represents biodiversity within a single forest plot; β diversities are divided into two levels, one is the β diversity between forest plots within a single forest type (hereafter, intra forest type β diversity), the other is the β diversity between forest plots from different forest types (hereafter, inter forest type β diversity). We found the taxonomic and phylogenetic a diversities differed between forest types, however, when the geographical and environmental variables were taken into account, the differences mostly disappeared. We also found the intra and inter forest type β diversities largely differed, and the overall intra forest type β diversity was smaller than inter forest type β diversity, regardless of the geographical and environmental variables were controlled or not.These findings suggest the influential factors of taxonomic and phylogenetic a and β diversities differ in the studied subtropical forests. Specifically, the geographical and environmental variables might play critical roles in influencing the forest taxonomic and phylogenetic a diversities, whereas the forest type is largely responsible for the forest taxonomic and phylogenetic β diversities. This study deepens our understanding of the biodiversity of major subtropical forest types in the subtropics, which could guide the formulation of optimized forest management strategies to preserve the regional biodiversity.