西南桦树冠与胸径生长关系研究

A Study of the Relationship Between the Crown Width and Diameter Growth of Betula alnoides

摘要: 以普洱和西双版纳不同海拔自然生长的西南桦（Betula alnoides）为研究对象，选择生长良好、周围无干扰的西南桦单株，研究西南桦胸径与冠幅间的关系，结果发现，西南桦在胸径长到45 cm~50 cm之前，其冠径比值为22.4~71.3倍，且有随着胸径增大，冠径比逐渐减小的趋势，而胸径生长到45 cm~50 cm以后时，其冠径比处于较为稳定的状态，冠径比值约为19.1~22.6倍。

Abstract: The relationship between DBH and crown width were investigated for independent and well-growing trees without disturbance in the natural stand of Betula alnoides in Xishuangbanna.It was found that the crown diameter ratio was about 22.4~71.3 times (the ratio of crown diameter to DBH) before DBH reached about 45 cm~50 cm.With the increase of DBH,the number of stands should be reduced accordingly.When the DBH reached above 45~50cm,the crown diameter ratio was basically stable,and the crown diameter ratio was about 19.1~22.6 times.