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林分密度控制图是七十年代从日本引进的,目前正在我国推广使用,它可用于森林定量间代、造林设计、森林资源清查等方面。它是以林分株数密度效应为理论基础,编制成数表,然后在双对数座标纸上绘制成图,其要素为等树高线、等直径线、自然稀疏线、等疏密度线和饱和密度线。在确定上述要素时所选择的数学模型因树种和林况等不同,其繁简各异。本文仅就确定饱和密度线的方法进行探讨。一、对饱和密度线计算方法的探讨林分在同一生长阶段,其单位面积产量随立木密度变化而增减的现象称为密度效应。它表现的特点为:单位面积产量随立木
The stand density control chart was introduced from Japan in 1970s and is being popularized and used in our country at present. It can be used in the quantitative intergenerational forest, afforestation design, forest inventory and so on. It is based on the number of trees density effect as the theoretical basis, compiled into a number of tables, and then plotted on double logarithmic coordinate mapping paper, its elements such as tree height line, equal diameter lines, natural sparse lines, such as density lines And saturation density line. The mathematical models chosen in determining the above elements differ in their complexity due to differences in tree species and forest condition. This article only to determine the method of saturated density lines are discussed. First, the calculation of saturated density line approach Stand in the same growth stage, the unit area yield with the stand density changes in the phenomenon known as the density effect. Its performance is characterized by: Yield per unit area with standing wood