| Based on the data, some aspects were studied in terms of the origin of semitropical nature reserves,species composition and flora interspecific association of communities, the character of community, interspecific association, structure and dynamics of communities, species abundance distribution and species diversity of communities. The results are as follows:(1) Modified projection pursuit technique was used to analyse the flora of thirty-nine Nature Reserves, which were divided into three kinds. The first was transitional zone from tropic to south subtropic area, the second was mid subtropic area, the last had temperate and subtropic transitional character. Analysis of Wuyishan Nature Reserve floristic geographical elements indicated that the percent of Pantropic elements were high. The results of life form and leaf characteristics indicated that phanerophytes were the main life form spectrum. Mesophyll,Microphyll,simple leaf and coriaceous leaf were the characteristics of leaf, which reflected habitat warm and wet. In addition, The origin of Wuyishan Nature Reserve was in the similitude of Longxishan,Tianbaoyan,Matoushan,Fengyangshan and Wuyanling Nature Reserve. So ecological characters were studied from different forest communities of Wuyishan Nature Reserve.(2) Communities in Wuyishan Nature Reserve had 86 families and 389 species. Communities in evergreen broad-leaved forest had 56 families,181 species, vertical structure of communities was very obvious, which could be divided into tree layer, shrub layer ,herb layer and layer between herbal plants.Basically,the shape of its tall trees were composed of Castanopsis eyrei,C. glauca (theumb.) Oerst and Castanopsis fabri etc, the shape of its shrub layer stemmed from Oligostachyum oedogonatum,Indocalamus tessellates and Castanopsis fabri etc. Communities in Mixed Phyllostachys pubescens forest had 64 families and 178 species, the structure of tree layer was simple, Phyllostachys heterocycla was the main species,shrub layer was rich in species compared with tree layer, which were composed of positive species, for example, Indocalamus tessellates and Maesa japonica,etc, but the dominate species was not evident; Mixed forests of coniferous and broadleaf had 40 families and 105 species, vertical structure of communities was obvious, species diversity in tree layer were abundant; Pinus taiwanensis communities just had 29 families and 70 species, most of the were Pinus taiwanensis.The mass of shrub layer were Indocalamus tessellates and var . Sinicum,especially Indocalamus tessellates. Rhododendron latoucheaecommunities were composed of 51 families and 143 species ,which small trees were more than tall trees.(3) The 2×2 contingency table, the analysis of different indiceed including the analysis of variance, x~ 2-test, interspecific association test and percentage co-occurrence were used to analyze the species association between 15 dominant populations in different communities. The result of analysis showed that significantly negative correlation exist among the 15 populations in evergreen broad-leaved and Phyllostachys pubescens communities, but the trend of correlation was feeble, which indicated that the communities were instable and they were in developed stage; Positive correlation existed among the 15 populations in mixed forests of coniferous and broadleaf and Rhododendron latoucheae communities, which indicated that they have arrived climax stage; The 15 populations of Pinus taiwanensis had no significant correlation.(4) Five species-abundance relationship models which were Log series,Log normal,Weibull,Geometric series and Broken-stick were used to analyze species-abundance relationship of five forest communities in Wuyishan Nature Reserve and checked by x~ 2-test. The results showed that Log series,Log normal and Weibull distribution were better models to characterize the species-abundance relationship. In addition, The practicability and operability of Log series and Weibull distribution were better.(5)Biodiversity was a key parameter in ecology, because both its importance in conservation biology and its role as a synthetic indicator of the organization of ecosystem structures and functions in relation to their origin and evolution. Plant species richness was considered to be a simple expression of species diversity, and the relationship between richness and diversity has been confirmed in several cases of pasture systems. The species diversity effect of different communities were measured by means of species evenness, species diversity index, species richness and total diversity index, based on the important values. It indicated that the evenness and diversity index of evergreen broad-leaved forest were higher and Pinus taiwanensis forest were lower, which conform to the result of total diversity. Otherwise, the diversity index showed that the descending trend from broad-leaved forest to conifer forest. At the same time, the actuality of Wuyishan Nature Reserve species diversity was explained by comparing with biodiversities of broad-leaved forest in other regions(6) The construction dynamic of each communities were analyzed by the number of individuals, the number of species, the sharing degree and the community lost stable rate for D.B.H class and highness class. It showed that the number of individuals and the number of species for the D.B.H class went with that of highness class, With the increasing of D.B.H class, the number of species were ascending then descending. Each communities had the structural dynamics of the sharing degree were from low-to-high changing process. The stability of evergreen broad-leaved forest community was the first, mixed forests of coniferous and broadleaf and Rhododendron latoucheae forest communities were second, Mixed Phyllostachys pubescens forest community was the last.
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