模拟间伐对树冠直径方差发生机制的研究

Mechanism of the Occurrence of Crown Diameter Variance After Simulation Thinning

有些收获表的主林木直径方差为负值，这在理论上是矛盾的。原因之一是在编制收获表的过程中，假定所有主林木的直径相同，没有考虑直径分布。该文在若干假定的前提下，在林木开始竞争时，通过模拟间伐，从理论上探讨树冠直径方差发生机制。

There are some contradictions in the yield tables, for example,the diameter variances of dominant trees are given in minus values. Although the reasons for these faults have not been clarified yet,the lack of the consideration of stand distribution is suggested to be one.Supposing that the trees are stationed at grid points with same size of the crown, from the very beginning of the trees competition, the mechanism of the occurrence of crown diameter variance is theoretically studied through the simulation thinning.