沙地樟子松人工林自然稀疏规律

Self thinning of even aged pure plantations of Pinus sylvestris var. mongolica on sandy soil

林分在自然稀疏过程中 ,与密度相关的死亡是由林木大小的增加引起的。因此 ,很自然地要选择反映林木大小的指标 ,来表示林木株数与林木大小的关系。选取林分总断面积作为林木大小的指标 ,建立了沙地樟子松人工林自然稀疏过程中林分密度与总断面积的相关关系 ,旨在为沙地樟子松人工林的合理经营提供依据。对自然稀疏 -3 / 2法则进行的评述 ,认为尽管没有充分证据表明斜率 -3 / 2存在的精确性 ,但它可以作为一个理想的常数 ,并且考虑到各种现实性 。

Since density dependent mortality is caused by the increase of tree size,it is more natural to choose an indicator of the size to express the relationship between the number of trees and the size.We chose the total stand basal area as the indicator of the size,and established an equation relating the number of trees to the total basal area of even aged pure plantations of Pinus sylvestris var. mongolica on sandy soil during their self thinning.We reviewed the -3/2 power law of plant self thinning,and suggested that although there is no satisfying evidence to support the accuracy of the slope of -3/2,it may be regarded as an ideal slope,and that with a view of various realities,we allow the existing of difference of the practical slope to the ideal one.