| The analysis on the forest community characteristics might throw a light on the understanding of the effects of human-caused disturbance on forest ecosystem. Based on the investigation(total area of plots: 5600m~2) to two kinds of communities, three conserved forest communities in Wanmulin Nature Reserve (C) in Fangdao town of Jianou City and four human-disturbed forest communities (D) in the same town with a similar ecological environment, we analyzed the effects of human-caused disturbance on the community characteristics including the vertical structures, the sorts of species and their quantitative characteristics, the species diversity and the spatial patterns of populations of evergreen broad-leaf forests in Jianou city of Fujian province. For the vertical structure of the communities, it could be ascribed mainly to the destruction of the upper communities of D that the whole vertical structure affected by the human-caused disturbance. The number of species was increased in D by the invasion of some heliophilous plants, especially in the layers lower than 6 meters, in which the numbers of individuals and species were remarkablely increased both. It was suggested by the sorts of species at each height that the succession of C communities came to a relatively stabilized stage whereas the D communities were evolving to the typical local vegetation types with more species because of the ceasing of human-caused disturbance and hereby the invasion and competition of new species. The result suggested that the species diversity of communities could be maintained and even then increased by the combination of a certain degree of human-caused disturbance and mountain closure. For the quantitative characteristics, the research on each layer below 10m height showed that, there are more shade species in C communities whereas there were more neutral and heliophilous plants in D communities. Moreover, at the layer below 3m height, each species attained...
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