Abstract:

Population diameter structure, life table, survival curve, and distribution pattern of Quercus variabilis in different disturbed conditions in northern slope of Bashan Mountain were studied. Since 1950, Q. variabilis population A declined gradually, because it distributed in the lower altitude, near to the villages，and was disturbed strongly by human activity. To the contrast Q. variabilis population B performed well, because it distributed in the higher altitude, far away the village, and was little disturbed by human activity. The results showed: Q. variabilis population A was weaker than Q. variabilis population B in the population regenerating ability, population B had abundant young individuals, and the trees derived from the seedlings took a larger proportion while population A had less young individuals and the trees from sprouting occupied a larger proportion; The survival curves of both Q. variabilis populations A and B in different habitats were Deevey III type, and the death rate was the highest during I, II, III size class; The proportion of sprouting seedlings increased gradually from size class I to III, because they were much better than the seedling from seed making use of spaces and resources; The distribution patterns of the two types of Q. variabilis populations in different habitats were aggregative. However, as the age increased, the intensity of aggregation decreased; According to the principal component analysis (PCA) of the main environmental factors that influenced the growth and developing of two Q. variabilis populations, the human disturbance and soil conditions were the most important factors. In the future, the habitat for population A should be protected from the human disturbance, mother trees should be kept to bear enough seeds. The cultural practices for the population B are to adjust the environmental factors and the relations among species, to promote the reproduction and seedling development and to thin the non aim species.

Key words: Quercus variabilis, population structure, distribution pattern, principal component analysis