天然林林分空间结构综合指数的研究

以常用林分空间结构参数（混交度、大小比数和角尺度）为切入点，以微观经济学中柯布 道格拉斯生产函数相关理论为基础，通过构建以混交度、大小比数和角尺度为“投入”与林分整体空间结构为“产出”的林分空间结构生产函数，定义了林分空间结构指数（FSSI）。同时，根据林分空间结构3参数的“三维散点图”中现实的林分空间结构向理想结构点变化的趋势，计算了林分空间结构距离（FSSD）。结合黑龙江省3个不同区域、不同林分类型的75块固定样地全面调查数据的林分空间结构参数、林分空间结构指数以及林分空间结构距离的计算结果，验证了林分空间结构指数和林分空间结构距离均能有效反映林分空间结构特征及其动态变化。可以认为，林分空间结构指数和林分空间结构距离是对目前广泛使用的林分空间结构参数的完善和补充，二者均能作为定量描述林分空间结构状态和变化的综合指标。 

A new composite index of stand spatial structure for natural forest.

Forest spatial structure index (FSSI) was defined with commonly used forest spatial structure parameters (mingling, neighborhood comparison and neighborhood pattern index) as the breakthrough point, referring to the thought of diminishing marginal benefit of Cobb Douglas production function in microeconomics and through constructing forest spatial structure production function with mingling, neighborhood comparison and neighborhood pattern index as the “input” and forest spatial structure as the “output”. Meanwhile, forest spatial structure distance (FSSD) was calculated according to the trend of a change from actual forest spatial structure to ideal structure in “three dimensional scatter diagram” of parameters of forest spatial structure. It is verified that FSSI and FSSD can effectively reflect the features of forest spatial structure and the dynamic changes in combination of forest spatial structure parameters, FSSI and the calculation results of FSSD obtained through complete investigation of 75 sample plots with different forest types in 3 different areas in Heilongjiang Province, northeastern China. It can be regarded that FSSI and FSSD perfect and supplement widely used forest spatial structure parameters. The two can act as overall indicators to describe forest spatial structure states and changes quantificationally.