Research on forest structure characteristics and biodiversity of closed evergreen mixed broad and needle leafforest type in Bidoup - Nui Ba National Park

Abstract

Bidoup - Nui Ba National Park is one of the four national biodiversity centers of Vietnam and the place contenting significantly scientific value.Tree species composition ranged from 36 - 50 species and there were more than 4 species that participated incomposition formula to creat many different dominances following height belt. With having the average density of 203 trees per plot, the distribution of tree number and diameter (N/D1.3) conformed to decreased distribution rule; meanwhile, the distribution of N/Hvndid not conform any researched rules. Biodiversity in the region was considered high with 61 species wererecorded in the total of 1,833
individual trees belonging to 27 families and many different life forms. Regeneration trees had some primarily species engaged in compostion formula such as: Castanopsis echidnocarpa, Symplocos racemosa, Rhododendron klossii, Eriobotrya angustissimaand Craibiodemdron heryi.
Average density of tree regeneration was 20.516 trees perha and divided into 4 height classes with the largest proportion (accounting for nearly 40%) at the height class of 1 - 2m. Natural regeneration was influenced sigfinicantly by the group factors of shrubs, vegetation, and terrian while the cover rate
had negligible impact