基于林分疏密度的不同尺度方形样地与美国FIA圆形样地聚类分析

Cluster Analysis of Different Sizes of Square Plots and FIA Plot Based on Stand Density

对我国传统森林资源清查体系与美国森林清查体系进行比较分析时,地面实测样地的比较成为首要问题,即如何确定一个适宜的指标,并以此为标准来选择一个与美国FIA圆形样地面积大小比较匹配的方形样地,从而为参考及引进美国森林清查技术提供依据。研究采用林分疏密度作为指标,应用聚类分析方法对调查结果进行分析,结果表明:我国20m×40m的方形样地与美国FIA圆形样地对林分的反映能力最为接近。

The forest inventory system of America （FIA） was compared with the traditional forest inventory system of China. There are many different aspects in the two systems,but the difference in ground plot should be considered first. An appropriate standard that can be used to select a square plot,which is well matched with FIA plot,were determined aimed to provide the basis for introducing the forest inventory system of America. A cluster analysis of the survey data was made by selecting the suitable square plot for FIA plot in terms of stand density. Result shows that a 20m×40m square plot is close to FIA plot in the reflection of forest stand.