非参数核估计在探讨天然林直径结构规律中的应用

应用非参数核密度估计理论和方法，对从吉林省汪清林业局抽取的１２块天然林样地进行直径结构模拟，结果表明：（１）当Ｗｅｂｕｌｌｅ及其它分布函数能很好模拟的样地时，核估计也能对该样地进行模拟，并且要优于分布函数法，（２）在分布函数不能描述林分时，核估计方法仍能描述该林分，并能取得很好的效果；（３）不论是天然林还是人工林均可用核估计方法对林分直径结构进行模拟，非参数方法可能成为一种有用的方法。

Applying Nonparametric Kernel Method to Probe the Diameter Structure of Natural Forest

The paper applys Nonparametric Kernel Density Assessment to simulate yield diametric distribution,the source comes from 12 blocks of yield randoms in Wangching Jilin Province. The results show:(1)If randoms can be discribed by Webull and other distributive functions,Kernel Assessment Method can also discribe it,moreover,superior to other distributive functions;(2)Kernel Assessment Method can discribe stand when distribution functions can not discribe it,at the same time,the result is obvious;(3)Both yield and plantation can be discribed by Kernel Assessment Method to analysis stand diameter structure. Nonparametric method perhaps be useful method.