Study On The Community Structure And Species Diversity Of Fagaceae Dominance In Montane Rain Forest In Bawangling,Hainan Island

There are two major types of Montane Rain Forest in Hainan, One is that Dacydium pierrei and Podocarpus imbricatus of Podocarpaceae is dominance in community and the other is that Castanopsis hystrix and Castanopsis tonkinensis of Fagaceae is dominance in community. The former distrbution is very prevalence and it is as preferred study object to study by most researcher, but the latter distrbution is more narrow and isn’t noticeed by scholars.For full understanding of the characteristics of Montane Rain Forest in Hainan,we use the conventional method of community study to research the community that lie on the elevation1000meter valley and Castanopsis hystrix and Castanopsis tonkinensis of Fagaceae is dominance in community. Our works include four parts species composition&physical characteristics, the areal-type,population pattern of the major population&the dynamic change and species diversity.The research results indicates:(1) In6000m2sample plot, there are249species that blong to84family and166genus.Among249species, there are Xylophyta192species,Herb33species and Liana24species. Xylophyta is main high strong tree.Herb is almost Pteridophyta.Liana is majority woody.Garroting and buttress root are few found in this region.In sample community the leaves are almost entire,leather, mesophyll and simple leaf and the life form are major Meso-Phanaerophyte.The community characteristices are fit for the high tempreture and wet environment.(2)The areal-type of sample plot is very complex.There are10areal-types,that tropical type is major and means the plants of sample community relationship with the plant of trocpial Asia is very close,temperate zone is second and indicate the sample plot community transition.The special species of China was not almost found in this sample community that because of the restrictive condition of areal-type of forest study.(3) In this plot,there are eight major tree species.By method of Variance/Mean, we found that Castanopsis hystrix, L. fenzelianus A. Camus and Sarcosperma laurinum are random distribution pattern and Castanopsis tonkinensis, Schefflera octophylla, Tarennoidea wallichii, Engelhardia roxburghiana and Meliosma angustifolia are cluster distribution pattern. By study on dynamic change of population distrbution pattern, we can draw a conclusion that there are five change types of different grade species.Castanopsis hystrix,Castanopsis tonkinensis, Meliosma angustifolia belong to the type Ⅰ of Cluster——Random——Random, Sch efflera octophylla belong to the type Ⅱ of Cluster——Cluster－Random, Engelhardia roxburghiana belong to the type III of Random——Cluster——Cluster, Sarcosperma laurinum and L. fenzelianus A. Camus belong to the type IV of Random——Random——Random, Tarennoidea wallichii belong to the type V of Random——Cluster——Random.By the analysis of change of these species distrbution pattern, we find that the change are because of the biology characteristices of these species itself, interspecific competition, intraspecies competition and environmental factor.(4)By study, we find that the minimum area of community is4800m2.There are rich species.We compare the species diversity between different height and different DHB.We find that the individual number relationship with height and DHB is negative correlation and may reflect by y=1177x-2.02and y=1216x-2.48.We find that the species amount relationship with height and DHB is also negative correlation and reflect by y=189.9e-0.36x and y=235.8e-0.53x.We find that Marglef exponent relationship with height and DHB is also negative correlation and explain by y=-7.45Ln (x)+19.86and y=-9.50Ln(x)+20.66.The Shannon-Winener exponent relation with height and DHB is also negative correlation and explain by y=-0.288x+4.601and y=-0.448x+4.866.But the Evenness indices is different that it relationship with height and DHB is positive correlation. Along with the height and DHB rises, the species abundance tend to uniformity, population configuration is more reasonable.In this region,there are more abundant species and the areal-type is very complex and population distribution pattern forming and changing have more different factors and between diversity with height and DHB is negative correlation.Small height and small DHB is very important,that we try our best to keep it natural and reduce human intervention, and we may first consider the small height and small DHB for protecting and remaining the species diversity in Bawangling, Hainan Island.