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以林分生长过程表中林分密度及相应蓄积为基础数据,用V=KN~(-a)m式求得的a值表明:大多数树种随密度范围的增大,其a值亦增,反之,则降低,多数北方用材树种a值超过1.5或显著超过2.0,且不同林分密度范围变化错综复杂,用二分之三乘则概括不了异常复杂的生物现象及林分的生长规律。a值的大小仅表明单位密度里林分蓄积的变化速率,並不表明树种林分蓄积绝对数量的变化规律。因此,仅用a值来分析、研究,判断树种或树种间林分蓄积的变化规律,并试图用a值大小归纳树种为某几种类型是缺乏充分理论依据的。国内外学者对a值做了大量研究,笔者仅就我国北方主要用材树种的a值进行了探讨。现将研究结果分述如下,请指正。
Based on the data of stand density and corresponding accumulation in the stand growth process table, the value of a calculated by V = KN ~ (-a) m shows that most of the tree species also increase with the increase of density range , Otherwise, the value of a in most northern timber species exceeds 1.5 or significantly exceeds 2.0, and the variation of different stand density ranges is complex. The exceptionally complicated biological phenomenon and stand growth law can not be summed up by two-thirds multiplication. The value of a indicates only the rate of change of stand volume per unit density, and does not indicate the variation of the absolute quantity of tree stand volume. Therefore, using only a value to analyze, study and judge the change rule of species or inter-species stand volume, and try to use a value to summarize the tree species for certain types is lack of full theoretical basis. Domestic and foreign scholars have done a lot of research on a value, the author only on the main timber species in northern China a value were discussed. Now the research results are as follows, please correct me.