| Jinyun Mountain Natural Reserve lies in Beibei district of Chongqing (29° 50' N, 106° 20' E). It is one of the first national scenery district. There are amount of plants and many varieties of forests in this region. In June ,1989, a great storm that had not happened before damaged the Jinyun Mountain.;It resulted in 17000 trees which diameter was larger than 12cm were cut down and the damaged range was 50hm~2.The process that the wind-damaged community has been restituted during 16 years is not only a sub-succession problem, but also an eco-system restoration's problem. Its scientific value, ecological value and social value are extremely important, which made practical and theoretical signification.In this paper, floric analysis, numerical classification, structure character of community, species diversity and interspecific association of the major species in Jinyun Mountain Nature Reserve in Chongqing was conducted by adopting quadrat method.1. There are 84 species of vascular plants in the sixteen-year wind-damaged community in Jinyun Mountain Nature Reserve, belonging to 38 families and 60 genera, in which the pteridophyte accounted for 3 families 5 genera and 5 species, the gymnosperm 2 families 4 genera and 4 species, and the angiosperm 33 families 51 genera and 75 species.2. The floric characteristics of the community:(1) The flora is complicated and transitional. The tropical families dominated thewhole vascular plants with the exception of 9 families, there are 17 tropical families which accounted for 65.38% of the total families. Moreover, the majority of them were 11 pan-tropical families;9 temperate families which accounted for 34.62% of the total families. Moreover, the majority of them were 7 north-temperate families. The tropical genera were the dominant genera with the exception of 1 cosmopolitan genera , there were 35 tropical genera, which accounted for 64.81% of the total genera. Moreover, the majority of them were pan-tropical and tropical Asian genera. There were 16 temperate genera, accounted for 29.63%, and 3 genera endemic to China, accounted for 5.08%.(2) The flora had come floristic constituents before Quaternary and retains many floristic element before Quaternary.(3) There were a little rare endangered plants and endemic plants.3. A variety of methods including the tabular comparison of data, the tabular comparison of similarity coefficient, the nearest method and the group-average method of hierarchical agglomerative classification were used to carry out numerical analysis for the sixteen-year wind-damaged community in Jinyun Mountain Nature Reserve. Based on the results, the 5 wind-damaged plots in Jinyun Mountain Nature Reserve were divided into 3 formations according to the important values of species in tree layer, they were Castanopsis carlesii formation, Gordonia acuminata and Cunninghamia lanceolata formation and Neosinocalamus affinis formation.4. Based on the data collected from sample plots with an area of 3400m2, we find the structure characteristic by analysing the life form spectrum, species diversity, horizontal and vertical structure of the sixteen-year wind-damaged community in Jinyun Mountain Nature Reserve. Results show that:(1) The analysis of the communities' leaf from spectrum shows that the five sixteen-year wind-damaged communities all have the characteristics of mid-subtropical broad-leaved evergreen forests.(2) The 13 dominant tree populations all belong to aggregated distribution. Some of them, such as Sapium japonicum, Cunninghamia lanceolata, Elaeocarpus japonicus and Pinus massoniana are in high aggregated degrees, meanwhile, Gordonia acuminata is in the lowest aggregated degrees. The community structure iscomplicated and the vertical level splits up more obviously. It is divided into Tree layer, Shrub layer and Herb layer. The vines are not abundant and tree layer can be divided into 1 -2 subordinate layers.5. The species diversity of the sixteen-year wind-damaged community in Jinyun Mountain Nature Reserve was analyzed, by using species richness, Simpson index, Shannon-wiener index and Pielou index, the result are as follows.(1) The sixteen-year wind-damaged community in Jinyun Mountain Nature Reserve had high species diversity index, which did not alter too much between investigated plots, the variation patterns of species diversity of the sixteen-year wind-damaged community in Jinyun Mountain were similar whichever the index was used.(2) Generally, the order of the magnitude of species diversity was : shrub layer >tree layer >herb layer.(3) The species diversity of the sixteen-year wind-damaged community was not affected by altitude, which indicates the consistency of species diversity in Jinyun Mountain Nature Reserve. At same altitude, the direction of slope is more affected the species diversity. Water and quantity of heat in the open slope are better than shade slope, so the species diversity in the open slope is higher than shade slope.(4) The species diversity of the sixteen-year wind-damaged community in Jinyun Mountain Nature Reserve was greatly influenced by human influences.6. Based on the 2X2 contingency table of different indices, the interspecific association among 15 common species in the sixteen-year wind-damaged community in Jinyun Mountain Nature Reserve were investigated. The results are following:(1) W-test indicated that negative correlation exists among the common populations, which suggests that the communities were processing.(2) During the 15 common populations in the sixteen-year wind-damaged community in Jinyun Mountain Nature Reserve. The proportion between positive and negative was almost equality, in which 2 species pairs showed extremely significant positive correlations, 2 species pairs had significant positive correlations, 1 species pair showed extremely significant negative correlations and 3 species pairs had significant negative correlations. The x2 text indicated that there were almost nosignificant interspicific association in most of the 105 species pairs, which reflects the independence of species pairs. The loose interspecific association is possibly related to the developmental stage of communities and ecological features of species. At present, they are processing.
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