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可持续森林经营理论为中期林业计划和收获调整提供了丰富的模型选择,其不同的方法可应用于各种特定的场合和不同经营类型。本文简要回顾了传统的森林计划方法,一种称为“多林分发展”的概念可以用于任意的经营系统,这个概念把森林看作由一系列林分组成,在每一个林分中可以预先制定多种经营措施的选项,每种选项都可以通过木材或其它产品以及消耗的资源计算出一个目标值。这种简单的概念可以应用到大量的不同森林经营场合,它为森林经营者制定切实可行的森林措施和评价森林经营计划提供方法。在本研究中,以德国北部一片包括21个小班的挪威云杉林班的一个中期计划为例,说明“多林分发展”这一经营系统在实际生产中的应用。每个小班具有不同的初始状态,每个小班预设了若干经营选项,根据小班的初始状态、生长模型为各种选项计算各时期的木材产出。在林班的水平上,经营目标方程包括两个组成部分:净现值和均衡木材收获值。用模拟退火的方法来优化总体目标方程值。优化的总体解决方案在为每个小班选定合适的经营选项的同时,在全林的水平上获得最优的经济和均衡产出组合。
The theory of sustainable forest management provides a rich model choice for mid-term forestry planning and harvest adjustment, and its different approaches can be applied to a variety of specific situations and different types of management. This paper briefly reviews the traditional approach to forest planning, a concept called “multi-forest development” that can be applied to any management system, a concept that treats forests as consisting of a series of stands, each of which A variety of management options are pre-defined. Each option calculates a target value from wood or other products and resources consumed. This simple concept can be applied to a large number of different forest management applications and provides a method for forest managers to develop practical forest measures and to evaluate forest management plans. In this study, a medium-term plan for a Norwegian spruce forest class in northern Germany that includes 21 small classes is used as an example to illustrate the application of the “multi-forest development” operating system in actual production. Each small class has a different initial state, and each small class presets a number of business options. According to the initial status of the small class, the growth model calculates the wood output for each of the various options for various options. At the forest level, the business objective equation consists of two components: the net present value and the equilibrium timber harvest value. The method of simulated annealing is used to optimize the overall objective equation. Optimized Total Solution The optimal economy and balanced output portfolio at the entire forest level is achieved while selecting the right business option for each subgroup.