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林带树木的生长发育直接影响林带结构的变化,进而影响林带的防护效益。本文在大量野外调查的基础上,对杨树林带树木的分化与树木分级及其应用等进行了研究。其主要结论有:影响林带树木分化的主要因子除遗传因素和栽植密度,以林带的边行效应是其另一主要因素;边行优势主要体现在林带树木最大年径均出在边行,边行平均直径大于内行平均直径;林带树木的分化时间是由树木直径离散度决定的,根据林带树木对林带结构的贡献和树木生长发育状况,半林带树木划分为4级;林带结构调控时,间伐对象主要为Ⅳ级木和Ⅲ_c、Ⅲ_d级木。
The growth and development of forest trees directly affect the changes of forest structure, and then affect the protection efficiency of forest belt. Based on a large number of field surveys, the paper studied the differentiation and tree classification of poplar trees and their application. The main conclusions are as follows: The main factors influencing forest tree differentiation are genetic factors and planting densities, and the sideline effect of forest belt is another major factor. The edge superiority is mainly reflected in that the maximum annual diameter of forest trees is at the side and side The mean diameter of rows is larger than the average diameter of rows. The differentiation time of trees is determined by the dispersion of tree diameter. According to the contribution of forest trees to the structure of trees and the growth and development of trees, the trees in the forest are divided into 4 grades. The main object for the class Ⅳ wood and Ⅲ_c, Ⅲ_d grade wood.