| Form.Taxus chinensis var.mairei is protecting plant in the first class, which is a precious and endangering plant in China In this paper, the quantitative characterics of Form. Taxus chinensis vsr.mairei population including age structure, spatial distribution pattern, growth dynamics of tree basal area, niche characterics, fractal dimension and competition between specises were studied using methods of mathematics ecology from the angle of population ecology of Form.Taxus chinensis var.mairei, then the prent state and the endangering causes were analysed. This research offers gist to protecting and enlarging the crude resourse of Form.Taxus chinensis vsr.mairei population, afforesting plantation and sustainable utilize for us. The research can offer some important references to the population ecology of endangerous plant, too.Based on the dates of two different circumstances, two standard life tables of Form.Taais chinensis var.mcarei population are founded by mathematical technique according to premising with "space deducing time", and the curves of survival rate, mortality rate and killing power were drew. The results showed both of the survival curves of population appeared to be a type of Deevey-III and the high mortality of seeding is one of the important reasons which caused Taxus chinensis var.mairei to be endangered, which badly limited the enlargement of Form.Taxus chinensis var.mcarei population. The spectral analysis of the population showed that there was a marked regularity of periodic in the process of natural regeneration of Taxus chinensis var.mairei, and it availed to the stabilazation of Form.Taxus chinensis var.mairei population.This paper presents the spatial distribution pattern and dynamics of Form. Taxus chinensis var.mairei population in Form.Taxus chinensis var.mairei community using six aggregate indices(C,I,I M, PAI,CA,), then analyze the causes of evolved pattern. The results indicated that the distribution pattern of seedling were all clumped in every plot, however, the distribution patterns of sapling, media tree and mature tree were mostly random. The trend of diffuse of Form. Taxus chinensis vsr.mairei population is very oblivious from seeding stage to mature tree stage. The patterns were consistant with the ecological and biological characteristics of Form.Taxus chinensis var.mairei which were valuable and rare and in severe danger.In this paper, Logistic model and Liu-Logistic model were proposed to approach thegrowth dynamics of tree basal area of Form.Taxus chinensis var.mairei population. The method of modified simplex was applied to optimize the models, and the fitting results show that Liu-Logistic model was more suitable than Logistic model to the actual growth trend of Form.Taxus chinensis var.mairei population, and the highest growth rate of basal area was the tenth age class, namely the phase when breast diameter was 68~76 cm. The growth dynamics of tree basal area of Form.Taxus chinensis var.mairei population in different altitude were discussed using the Liu-Logistic model, and the results showed that the altutide of 790 meters is more suitable to the survive of Form. Toms chinensis var.mairei population than 990 meters.Plot sampling was selected and dynamic analysis was used to study the height structure of Taxus chinensis var.mairei population, and the quadrate picture of height structure and the curve of survival rate were drew. The results showed the height stucture wsa "revere-J" and the survival curve was likely a linear with a little protruding. It was belonged to stable type. The seeding accounted for 91.48% of total number, and the mature tree of H: 5~7m class for 227% whose density was just next to the seeding class. The results of intraspecific and interspecific competion formed the different individual height of Taxus chinensis var.mairei population.The fractal dimension of Taxus chinensis vsr.mairei were calculated on three indices : crown breath, base area, volume. At the same time, the relativities of linear regression and nonlinea...
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