浙江省毛竹直径与年龄的二元Weibull分布模型

Diameter-Age Bivariate Weibull Distribution Model for Moso Bamboo Forests in Zhejiang Province

利用2004年复查的浙江省森林资源连续清查体系4250个固定样地中的245个毛竹纯林样地数据,用具有严格概率模型性质的二元Weibull分布模型描述浙江省毛竹直径与年龄的二维结构,并讨论二元Weibull分布模型的生成函数,给出几个不同形式的表达式,指出模型良好的概率模型性质。一元Weibull分布模型的直径、年龄模型分别是二元模型的边际分布,而且用边际分布求得的参数与用联合分布求得的参数也很接近。本研究是省级地域的毛竹宏观模型,该模型也可尝试应用到林分水平,以及其他类型森林。

A bivariate Weibull model was used to describe the diameter-age 2-dimension structure of Moso bamboo （ Phyllostachys Pubescens ） forests in Zhejiang province. Date from 245 permanent Moso Bamboo plots out of total of 4250 of Zhejiang Continuous Forest Inventory System were used in this study. These plots were resurveyed in 2004. Survival function of the bivariate Weibull distribution model was discussed in detail, and several expressions of the model were proposed. Both the univariate Weibull diameter and age models were marginal distributions of the bivariate Weibull model. Parameters estimated from marginal distributions were very close to those from the joint distribution. Although this study was on bamboo forests at provincial level, the model and the method developed in this research could be used to other forest types such as arbor forests, at different scales.