Study On Stand Growth Models For Pinus Yunnanensis

Stand growth model is used to predict stand growth in natural conditions, and is also the basis of predicting the influence of management operation on stand growth, making optimal management strategy and directed cultivating. Its application will provide us with the necessary condition and basic method to develop the new forest management basic theory and utilize the modern forest management technology.This study is use the second class information of forest investigation from Yi PingLang, and study the subcompartment data of Yunan pine. In this paper, correlation has been analysis between the stand description factor such as height, diameter, age, volume of per hectare and number of stems per hectare. Establishment of single-shape height-age directed curve, classified height-age directed curve, multi-shape height-age directed curve. And site index table was constructed. The density index has been analysis. Stand height-age model, stand diameter-age model, stand volume growth model of pinus yunnanensis stand has been established. The process of building polymorphic height-age models were discussed and polymorphic growth models of stand was established study area.Site index is the precondition of reasonable sylvicultural layout and dealing in designing layout, it is also one important factor of the stand growth model. In the single-shape curve method, the site index curve is based on average oriented curve, outspread the opposite tree height method, the measured data method and fluctuant coefficient method as a set of curves in a trend towards similarity and the same type. But the oriented curve is closely related with the exponential distribution. To ensure the exactitude of oriented curve, the sample of each site must distribute well-proportioned in each age classes, it's hard to achieve in practice. In the multi-shape curve method, supposing the different site factors are different from stand height-age curves. Using multi-shape curve with different shape and different development trend describe the growth in each site factors. When the plots have different age classes and different site, it will result in the oriented curve's slope on the low side or on the high side. The multi-shape curve can resolve it. So it is the most important thing for working out the site index table using multi-shape oriented curve method.It is important for classification of data in constructing directed curve and making site index table using methods of polymorphic curve. In this paper, classified result using...