兴安落叶松过伐林林木分类管理技术

Classification and management technology of trees in overcut forests of Larix gmelinii

从兴安落叶松Larix gmelinii林分整体出发,围绕优化林分结构,调控演替,促进林分生长,提高林分生产力和自然更新能力为目的,根据林木个体大小、年龄、位置、作用、用途和其他重要程度,提出了林木分类管理方法与技术。(1)目前林木分类方法应为一般性的指导,针对现实林分,要注重考虑林木格局、更新、演替、空间利用等因素,以符合结构优化经营要求。(2)将林木分为用材树、用材后备树、伴生树、演替树、母树、更新幼树和间伐树等7类,从而明确了结构优化目的性,有效分解了结构优化途径,方便抚育经营操作,可为确定合理的间伐强度及方式提供依据。(3)不同结构的林分各类林木株数比例不同,相应的间伐强度、间伐树组成也不同。伐除一定比例的被压木以外,选定间伐树时应考虑主林层、演替层和更新层等各个层次。(4)依据林分结构现状、各类林木株数比例及构成,从林分整体上考虑优化问题,确定了较低间伐强度(5.1%~19.5%)。这将更有利于减少干扰,促进更新,调整树种组成,优化林分结构。

To optimize forest stand structure, to regulate succession, to promote the development of a forest stand, and to improve stand yield and natural regeneration capacity, technologies for classification and management methods and were proposed based on scale, age, location, function, and application of an individual forest for an integral forest stand. The procedure included four parts：（1） the existing forest stand classification method was used as a general guide for such factors as distribution patterns, regeneration, succession, and space utilization so as to match requirements for structurally optimized operations.（2） The forest in this study was classified into seven categories, i.e. timber trees, timber reserve trees, associated trees, successional trees,seed trees, regeneration trees and trees for intermediate cuttings. This structural classification facilitated forest tending and provided a basis for determining the proper intensity and method of intermediate cuttings.（3） For intermediate cuttings, the number of tree varieties, the cutting intensity, as well as the composition of trees varied with changes in structural differences of forest stands. Except for the cleaning of suppressed trees under a certain size, arrangement of the main story, the successional story, and the regeneration story should be considered when selecting trees for intermediate cuttings.（4） Optimization should be considered from the aspect of a general forest stand based on existing stand structure as well as tree proportion and composition to achieve a low intermediate cutting intensity of 5.1%-19.5%. In this way, disturbance will be reduced, regeneration will be improved, tree varieties will be regulated, and forest stand structure will be optimized.