Comparative study on vegetation of coniferous broad-leaved mixed forest and broad-leaved forest in eastern Guangdong

The coniferous broad-leaved mixed forest in Xiangshui, Longchuang County and broad-leaved forest in Wanlugu, Dongyuan County in eastern Guangdong province were taken as sampling areas, the structure and species diversity of the two communities were comparatively analyzed by using quadrat investigation. The results showed that there were 25 plant species belonging to 17 families, 25 genuses in the coniferous broad-leaved mixed forest in Xiangshui,Longchuang, while Theaceae, Pinaceae, Rubiaceae, Myrtaceae, Gleicheniaceae plants were dominant ingredients in this community. There were 32 plant species belonging to 23 families, 29 genuses in the broad-leaved mixed forest in Wanlugu,Dongyuan, while Araliaceae, Euphorbiaceae, Saxifragaceae, Rubiaceae plants were dominant ingredients in this community.The analysis on plant richness and Shannon-Winner index, Simpson diversity index, probability of inter-specific encounter and evenness index showed that the coniferous broad-leaved mixed forest in Xiangshui had a lower plant diversity, less uniform distribution of species and probability of inter-specific encounter than the broad-leaved mixed forest in Wanlugu,Dongyuan. Both of the communities were dominated by phanerophytes and had obvious tropical nature. The analysis on age-structure of dominant populations showed that the coniferous broad-leaved mixed forest were in a decline state while broad-leaved mixed forest were in a growth state.