Studies On Community Structure And Species Diversity Of Tropical Rain Forest In Diaoluoshan Natural Reserve, Hainan Island

This paper is a case study of biodiversity and ecosystem conservation research located in Diaoluoshan Nature Reserve, based in HainanProvince. The Diaoluoshan Nature Reserve research area consists of fifteen different sample areas of various altitude and terrain environments (including four sample areas of pristine tropical rainforests and other areas that are categorized as secondary tropical lowland rainforests). The environmental and biological diversity of Diaolushan research area allows for the examination of tree layer, shrub layer, and herb layer ecosystem characteristics, species diversity, and ecological structure.(1) All kind of distribution of the altitude ranges from200m-1130m, a total of108families of vascular plants,330genera. Ferns7families,8genera,10species; gymnosperms2families,4genera,6; dicots86families,283genera,684species; monocots13families,35genera and49species.Contains belong to most of the family of Rubiaceae, Euphorbiaceaec, Annonaceae, etc; Species most families is in turn contained Lauraceae, Euphorbiaceaec, Fagaceae, etc.The main species of primitive tropical lowland rain forest are Diospyros howii, Mallotus hookerianus Muel; the main species of primitive tropical montane rain forest are Castanopsis chinensis, Dacrydium pierrei and so on; the main species of secondary tropical lowland rain forest are Amesiodendron chinense, Litsea coreana and so on; secondary tropical lowland rain forest was dominant species in Schima superba, Vatica mangachapoi; Southwest slope the secondary tropical lowland rain forest was dominant species in Schefflera heptaphylla, Meliosma angustifolia etc.Different altitudes of pristine tropical rain forest tree height had no significant difference; Diameter at breast height difference significantly; Density difference is significant. Different slope direction (southwest of north slope and south slope and slope) of secondary tropical lowland rain forest, the arbor tree height difference significantly; Density of diameter at breast height difference significantly, there was no significant difference.(2)108families of plants can be divided into12distribution types, which the world of the bucco to17families and15.74%of the total number of subjects; the tropical distribution80families, accounting for74.07%, the temperate11families, accounting for10.19%. Tropical sub-bucco dominant position in Hainan Diaoluoshan flora.12distribution type, the largest proportion in the case of tropical Asia and its variants, a total of98genera, accounting for29.7%of the total genera of the flora; followed by pan-tropical distribution and its variants genera,80genera,24.24%of the number of total genera, two distribution types occupy a large proportion of a total of53.94%.(3) Selection of original primitive tropical lowland rainforest, tropical montane rain forest, different slopes of secondary tropical lowland rain forest species diversity of. Primitive tropical lowland rain forest and montane rain forest, shrub layer evenness index is higher than that of tree layer and herb layer; Simpson index and Pieluo index in the two vegetation types little difference in herb layer; Simpson index is low.PCA is used to sort, the original tropical lowland rainforest and primitive tropical montane rain forest and different slope direction of secondary tropical lowland rainforest results show:indicator species of primitive tropical lowland rain forest is Mallotus hookerianus, Symplocos lancifolia, Diospyros tutcheri; indicator species of primitive tropical montane rain forest is Dacrydium pectinatum, Machilus monticola, Castanopsis chinensis and so on; indicator species in southwest slope forest is Sarcosperma laurinum, Heritiera parvifolia, Canarium album; indicator species in secondary forests on northern slope of the Gironniera subaequalis, Ficus vasculosa, Diplospora dubia; indicator species of secondary forest was Schima superba, Lithocarpus silvicolarum, Castanopsis hainanensis etc.(4) Select two same aspect, the same recovery phase, but at different altitudes in the tropical rain forest plots tree layer species interspecific association. The results show that the in different altitudes rainforest, all species within the community overall was a significant positive association; conducted chi-square test two different altitude rainforest plots20dominant species190species found mostly present in the species on no links; two different altitude tropical rainforest species coupling ratio and intensity variations show that the species proportion of positive and negative links increases with the increase in altitude, no links proportion with the increase in altitude.