Studies On Quantitative Characteristics Of Castanopsis Carlessii Population In Castanopsis Kawakamii Nature Reserve

Population ecology of Castanopsis carlessii and its community ecological charactertics in different types communities in Castanopsis Kawakamii nature reserve in Fujian Province were analyzed and discussed by quantitative statistic method in this paper, including size structure, spatial distribution pattern, life process of the population, the growth of tree basal area of Castanopsis carlessii population, as well as studies on the niche characteristics of main tree population in Castanopsis carlessii forests, the feature of its community.The results indicated as follows:Five probability models are applied to analysis the structure features on diameter distribution of 4 main tree populations in natural forests of Castanopsis carlessii. The results show that weibull distributionis is the best fitness to express the structure of diameter distribution of main tree populations in natural forests of Castanopsis carlessii; Diameter distributions of Castanopsis carlessii population in different main communites all obey Beta distribution model;and that Normal distribution second; The distribution and normal logarithmic distribution did not obey very well. skews are most positive and crests are all negative. Which suggest that the range of diameter distribution are wider and the number of mid-size wood is in the majority. The relationship of parameters of diameter Beta distribution in Castanopsis carlessii population with average D.B.H in natural forests is remarkable. The resulting principle will provide an important guide for natural forest management and survey.Based on the life table of population and the theory of survival analysis, the authors worked out the life table of Castanopsis carlesii population in natural forests of C.kawakamii, drew the curves of mortality density function, hazard rate function and survival, and Analyzed the population dynamics. The results show that the population had one peak of mortality,and the survival curve of the population trended to the type of DeeveyⅢ.The spatial distribution pattern and dynamics of Castanopsis carlessii population were presented using aggregate indices, lwao's equation and Taylor's model in this paper, then the causes of evolved pattern was analyzed.The results indicated that the distribution patterns of seeding were all clumped at mature tree and seeding stage in every community.The intraspecific and interspecific competitions of Castanopsis carlessii in ten communities were quantitatively analyzed by using Hegyi's competition index model for individual tree intraspecific competition intensity in this species reduced with the increase of diameter class of the tree. The competition intensity among each pair of species was in the order:Castanopsis carlessii- Castanopsis carlessii>Castanopsis carlessii-Schima superba>Castanopsis carlessii-Lithocarpus glabra>Castanopsis carlessii-Cunninghamia lanceolata(Lamb.) Hook> Castanopsis carlessii-Choerospondias axillaries> Castanopsis carlessii-Castanopsis eyrei(Champ.)Tutch>Castanopsis carlessii-Castanopsis Kawakamii> Castanopsis carlessii-Machilus velutina Champ>Castanopsis carlessii-Cinnamomum subavenium Miq> Castanopsis carlessii-Pittosporum tobira>Castanopsis carlessii-Elaeocarpus sylvestris(Lour.) Poir> Castanopsis carlessii-Photinia davidsoniae Rehd. The relationship of the competition intensity between the competitive tree and the objective tree and the individual size of objective tree obeyed power function rule and there was significanty negative correlation between the competition intensity and the individual size of objective tree. The model can be applied to predict the competition intensity in forest of Castanopsis carlessii.In this paper, Liu-Logistic model was proposed to approach the growth of tree basal area of Castanopsis carlessii population.The method of modified simplex was applied to optimize the parameters of model, and the fitting results showed that Liu-Logistic model was suitable to the actual growth trend of Castanopsis carlessii population, and the highest'growth rate of basal area was between the fifth and sixth age class, namely the phase when breast diameter was 26-32cm.In the paper, the tree population in Castanopsis carlessii forests, have been analyzed by quantitative mehod at the natural reserve of Wanmulin.The niche breadth, niche proportional similarity.and niche overlap of main tree population in Castanopsis carlessii forests were measured by taking community composition types as one-dimension resource stages, and important value as the resource state descriptor of niche.The results indicated that Castanopsis carlessii had higher niche breadth value and would sustain for a long time;all the dominant populations showed some adaptation to the community environment. In some degree, this results showed the succession tendency of the ecological system of the forests.The results would offer scientific theories for reserving, community structure and dynamic prediction of Castanopsis carlessii forests.