关键词: 分形维数, 分形维数

Abstract:

In order to optimize spatial structure of forest types of the Dongting Lake wetland, making full use of water conservation, soil conservation, climate regulation and other functions of the wetland forest, the author took the forestry farm secondary forest in Longhu Mountain in southern Dongting Lake wetland as the study area. Based on the theory of modern forest ecology and forest management and the existing stand spatial structure analysis methods, the author made use of mingling index and neighborhood comparison to analyze the stand tree species space segregation and the degree of size differentiation of individual trees, eventually, came up with a new method which was based on uniform angle index and spatial density index to analyze stand spatial distribution pattern, which made up for a shortage that traditional research methods could’t exactly reflect individual distance between the trees by neighborhood pattern. The results showed that the mingling indexes of southern Dongting Lake Longhu Mountain forest farm secondary forest sample plot 1, 2, 3, 4 were 0.29, 0.43, 0.46, 0.16, belonging to the transitional type of the mingling of low and moderate and the segregation of tree species was not high, which was due to human interferences with times; that the average neighborhood comparison were 0.45, 0.43, 0.7, 0.22, the grow superiority of the volunteer was obvious; and that the average uniform angel indexes were 0.65, 0.47, 0.53, 0.40, tree distribution pattern was on the between of ball and random distribution, closed to natural random distribution. So the stand spatial structure of Longhu Mountain forest farm secondary forest community was appropriate to research recover the forest ecosystem spatial structure and manage close to nature in the wetland area of the Dongting Lake.