Community Structure and Species Diversity in Tropical Cloud Forests

Abstract

Stand structure and species composition and diversity are the essential characteristics of ecological communities and often related to ecosystem processes and functions. However, these characteristics of the tropical cloud forests in Hainan Island are still poorly studied. This chapter aimed to fill this gap to a certain degree, paving the way for further revealing species coexistence and biodiversity maintenance. Based on the plots established in Bawangling, we compared the community structure and species composition and diversity of the two different types of TCF: tropical montane evergreen forests (TMEF) and tropical montane dwarf forests (TMDF). We found that the Sørensen index between them was 0.71. In both TMEF and TMDF, Lauraceae was the most dominant family, while Rubiaceae and Fagaceae were also the dominant families. TMDF was characterized by strong species monodominance that the importance value of Distylium racemosum was larger than 10, while TMEF was dominated by 5 species (Syzygium araiocladum, Distylium racemosum, Cyclobalanopsis disciformis, Psychotria rubra, and Syzygium buxifolium) with the importance values ranging from 5.20 to 7.12. Compared with TMDF, TMEF showed low stem abundance but high values of species richness, bootstrap estimator, and first and second Jackknife estimators. The logistic model provided better fits on the species accumulation curves of TMEF and TMDF than the power-law and exponential models. In general, trees in TMEF showed significant higher values of the mean height and diameter at breast height but lower stem density than those in TMDF. Our results indicate a high similarity in species composition and the significant differences in species diversity and community structure between TMDF and TMEF. Such differences could be attributed to environmental conditions.KeywordsStand structureSpecies compositionPlant diversityTropical cloud forest