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Stand structure is an important content of the stand characteristics, the use of forest protection, forest management, forest health assessment of forest-related research. The spatial structure is an important aspect of the stand structure is an important complement to traditional lack of stand structure the spatial distribution of information. The National Nature Reserve Baotianman Oak Natural Secondary as the research object, the use of 32 temporary plots, respectively, from the species composition, diameter distribution, stand the basic structure of the tree height structure expressed. Then use the 10 permanent plots data for spatial information, in ArcView3.2 software, combined with Excel to calculate the distribution type index method and from the analysis of the spatial distribution pattern of the forest, and then mixed degree, size number The angle scale three spatial structural parameters are described in detail analysis of the spatial structure of the stand, to provide a basis for better protection and utilization of forest. Studies have shown that the basic structure of the stand: (1) species composition analysis of the basic characteristics of each species and important value: the tree species richness and Oak the absolutely dominant tree species, followed by, , the short handle serrata trees and cork oak ? diversity index of three different forest types of analysis, results have some differences in species diversity index of forest types, but reflect the same trend: the sharp teeth of Quercus glandulifera serrata forest and a short handle serrata cork oak forest diversity index at a relatively high position, Sharptooth oak forest at the lowest diversity index. (2) The diameter distribution: application of probability density function to fit the the sharp tooth oak seven major species, known by the chi-square test, with five of these functions are not well fitted sharp-toothed oak fitting than the other species , in which the Weibull distribution distribution fit best, Bata followed by the distribution of these 6 species in diameter. Analysis of the number of features is known throughout the stands, the trails order trees majority; the short handle serrata tree of incense, Sam aggregata diameter class distribution of the degree of dispersion, the other four species DBH classes small discrete and concentrated. (3) The tree height distribution: the basic characteristics of the tree height factor analysis showed that all sorts of change between the average high tree, little change in the standard deviation, and the changes in the standard deviation of all sorts; For tree species, several main tree species emerged as most forest trees located near the average high asymmetric hilly curve the middle wood up to the the peak the upper right of the wood is generally less. Cork oak distribution in the upper layers of the stand and Oak in the middle and upper classes, of linden and Sam aggregata distributed in the lower stand. 2-parameter Weibull distribution function of several major species fitting, chi-square test results show that the sharp-toothed oak species fit better with the diameter distribution laws. Application TREE PATTERN calculated aggregation index method based on the distribution of the plots of several different indicators of the index and the distance method, a comprehensive analysis of the results that this survey II, III, IV age class Oak Natural secondary forests are randomly distributed, the distribution of the same type, but each index value reflects: three age class randomness differ Age II minimum, that is with a certain degree of aggregation characteristics by age class in turn, the degree of randomness increased. The spatial structure parameters were analyzed: (1) the mingling of Oak Natural Secondary analysis results show that the region stands mingling generally low. Age mingling change the level from younger to older age class mingling has increased. Mingling between the different species showed significant differences. Sharp tooth oak mixed low, other species mostly mixed strength and extreme intensity mixed. (2) The size analysis in diameter factor, the average diameter size of each age class little change than the value, but the size of each species than the number of the frequency distribution of changes in the larger, dominant tree species in general lower than other species. Among species of incense, Sam aggregata, short serrata tree by the strong inhibition in the stands at a disadvantage and Oak has been in a dominant position, along with increased age class, this advantage Status weakened. In tree height factor, the trend for each age level species generally and changes in diameter, correlation analysis showed that the variation of the two, in the reflection of the age class stands and tree species growth advantage, strong consistency. (3) the angular scale analysis shows that different age classes angular scale changes is insignificant, Age II maximum of 0.511, according to the criteria, Ⅱ, Ⅲ, Ⅳ three age class are randomly distributed state. Angle index value from the point of view, II age class was too large, relatively III, IV age class the partial aggregated distribution characteristics, distribution to a random distribution of growth from the younger age level to senior level, stand by the beginning of the gathering and gradually stabilized. From the species, the majority of species around the four recently adjacent wood randomly distributed, absolutely uniform distribution of each species in the surrounding forest is very little, almost nothing.
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