| In this present study, we employ the quadrat method to make a survey for the ecological environment and community characteristics of the rare endangered plant Calophaca Sinica in Tianlong Moutain National Forest Park and make a classification and ranking with TWINSPAN. In the results from TWINSPAN,53quadrats are divided into14ecological associations, further, C. sinica has distinct ecological advantages in the community and a certain decisive effect.In this present study, the DCA in the quadrat has revealed the relationship between the53quadrats and environmental factors of the soil moisture, and, in the horizontal direction, moisture content from left to right has been gradually increasing. The ranking analysis of DCA of plant has better reflected the interrelations between the preponderant plants and the environment. And in the abscissa, the58plants are ranked from left to right to represent the order from the hardy plant to not hardy plants. The first axis of the DCCA analysis basically reflects the altitudinal gradient of the plant community and the intensity of manmade interference. Following the DCCA, the first axis shows changes of the altitudinal gradient, that is, the manmade interference has been gradually decreased with the reduction of altitudinal gradient. The second axis which reflects the slope that the plant community lives in, and the thickness of the litter layer, among which the slope has strong relations with the litter layer in the second axis. The arrow of the slope is the longest, thus, following DCCA, the second axis shows that the slope from the bottom to the top is gradually decreasing, meantime, the thickness of litter layer is increasing. The analysis of environmental factors has shown that the elevation and manmade interference has the relations of notably positive correlation, which is determined by its elevation of Tianlong Moutain National Forest Park:the manmade trace is gradually obvious with the rising of elevation. The relations between the slope and the thickness of litter layer are remarkably negative correlation, which better reflects the changes of growing environment of C. sinica.The analysis of the diversity of plant community in C. sinica community indices are subject to natural as well anthropogenic factors. Adequate sunlight and less human interference contribute to the higher species abundance and evenness in the communities dominated by C. sinica. Meanwhile, the regression analysis shows significant correlations between6out of9pairs of soil factors. Zinc content is correlated to8community indices and potassium and phosphate are each to6community indices.In C. sinica community structures and dynamic research, we employ the survival analysis and spectral analysis to analyze the diameter structures of C sinica and static life table, and design the analysis of the survival curves, and analyze the periodicity of population quantity. Results will be listed as follows (1):numbers of the seeding of C. sinica population is large, the population with middle diameter is stable, and numbers of top level is obviously decreasing due to the physiological recession and the influence of environmental factors;(2) the survival curves of C. sinica community presents as Deevey-II type. Its dynamic performance has the features as follows:slowly increasing in the early stage, rising and falling in late-mid stage, and decreasing in late stage;(3) the rising and falling of C. sinica community has minor cycle and no great changes, which shows its stability. |
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