Research On The Influence On Density Of Oak Forest Stand In YunMeng Mountain And The Model Fitting

To illustrate the growth rule of water conservation forests in Beijing mountain area, this paper mainly studies the effects on density of water conservation forests of forest stand growth, and on the site factor (including elevation, slope, slope to, soil thickness) of forest stand growth. Data on forest management inventory of YunMeng mountain forest area in Beijing miyun county,analysis of the status of this water conservation forests, including the age group distribution; Elevation distribution, distribution of accumulation and area on different elevations; distribution of accumulation and area in different slope group; distribution of accumulation and area on different slope aspect; distribution of accumulation and area in different canopy density group. Use standard method to survey oak secondary forest, which specifications is0.1hectares. Survey and record the number of hectares of crown density, tree species composition, slope, aspect and position of the slope, altitude, type of soil, species of bush and herb, diseases and pests, etc for the corresponding. Combined with the relevant data of the forest, choose the Richards growth model and the polynomial model to fitting the tree height and DBH conservation of this water conservation forests.The result shows that:the two models’correlation coefficient were both high of the12sample plots, which at0.7above, and12samples with different forms of the model are fitting correlation coefficient slightly high and Richards model. The highest correlation coefficient of Richards model is0.856of9sample plot, which regression equation is H=18.808(1-e-0.05D)0.784;and the highest correlation coefficient of polynomial model is0.867of15sample plot, which regression equation is H=-2.525+1.592D-0.046D2. So both of the two models can be used to describe growth rule of tree height and DBH, and to predict the production and consumption of resources stand, for forestry management production and provide decision basis for update technology, improve the management to the macroeconomic regulation and control ability.Most secondary stand density and the average DBH negative correlation between the relationship. When stand density increases, the trees with average DBH reduced, this law is universal. The conclusion of density and tree height is inconformity; This shows that evaluate density for the tree height, the influence degree is less than for DBH;The relationship between density and trees accumulation per is negative correlation. Through the research of the status and conservation of water supply to master its growth rule, facilitate optimization stand structure and improve the forest tree growth conditions, enhance forest resistance and promote the forest tourism development, lay the foundation for the further development and utilization.