Research on biodiversity in dominant Guangdong-Castanopsis eyrei communities

For trees with DBH ≥ 1 cm, we recorded species name, DBH, height, and location within Castanopsis eyrie (Champ.) Tutch. community plots in Shimentai Reserve in northern Guangdong and Xiangtoushan Reserve in central Guangdong. Plant composition, distribution pattern, dominant species, and species diversity of the communities were analyzed. Results showed that there were 112 species of vascular plants belonging to 36 families and 54 genera in the Shimentai plot, and 109 species of vascular plants belonging to 36 families and 59 genera in the Xiangtoushan plot. Both communities showed observable tropical to subtropical transition. The Shimentai plot was closely related to eastern and central China, whereas the Xiangtoushan plot had more connections to western Pacific islands, namely Taiwan and Japan. Comparative study of community characteristics in the two regions showed a high similarity at the community level and similar plant diversity indices. However, latitude was not the determining factor of plant diversity. Microenvironment, community succession processes, and human factors had greater influences on plant diversity of the local communities.