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林业上一般把树木材积的连年生长量与平均生长量相等时树木的年令称为数量成熟令。确定树木是否达到数量成熟通常是分析解析木材料之后才能确定。那么,如何确定立木是否已经达到理论上的数量成熟令呢?这就是本文所要阐述的问题。按树木的生长规律,树木的数量成熟令一般是在树木生长的近、成、过熟阶段。此时,树木生长逐渐缓慢并趋于停止,高生长接近停滞。近年来对千形的研究结果表明:树干纵断面的形状可以用相对高的函数来表示,即直径生长在树高方向变化规律是一定的。基于以上各点,我们做如下分析:从树干上任取一微段,长度为△H、将其横断面近似看成圆形。设第n年时直径为D,第n+1年为D+△D,根据平均生长量,连年生长量和数量成熟令的定义,有下列关系:
In forestry, the year of trees is generally called the number of mature orders when the annual growth of tree volume equals the average growth. Determine whether the number of trees reached maturity is usually analyzed and analyzed wood can be determined. So, how to determine whether the number of trees has reached the number of mature theory? This is the problem to be elaborated in this article. According to the law of the growth of trees, the number of mature trees is usually in the trees near, into, overripe stage. At this point, the trees grew slowly and tended to stop, with high growth approaching stagnation. In recent years, the results of the research on Chia-shape show that the shape of the longitudinal section of the tree trunk can be expressed by a relatively high function, that is, the variation of diameter growth in the tree height direction is certain. Based on the above points, we do the following analysis: Take a short segment from the trunk, the length of △ H, the cross-sectional approximation as a circle. Suppose the diameter is D at the n th year and D + Δ D at the n + 1 year. According to the definition of the average growth amount, annual growth amount and the number of mature order, there is the following relationship: