非线性树高曲线模型的研究

Research on Nonlinear Height-diameter Models

引入失拟检验的理论和方法检验了树高曲线模型的适度,应用全模型和选模型的检验理论和方法对3参数模型的某个参数取定值作了检验,结果表明2参数模型描述树高曲线已经足够。比较了6个2参数树高模型,常用的幂函数式H=aDb和双曲线式H=aD/(D+b)以及本文提出的Richards式的特例即H=a(1-e-0.05D)c均表现良好,推荐作为基本的树高曲线模型。

The lack of fit test was introduced to test aptness of some height diameter(H D) models. The full model and reduced model test were employed to test whether it was reasonable to set some parameter of three parameter H D models a fixed value,with the result that two parameter models were enough to describe H D relationship. With the comparison of six two parameter H D models,the commonly used power function H=aD b ,the hyperbolic function H=aD/(D+b) and the specail case of Richards function suggested by this paper H=a(1- e -0.05D ) c gave the most satisfactory results,thus were recommended as the basic H D models.