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现有的几个经营异令林的数学模型,按照它们应用的对象可划分为两类:一类是林分模型,另一类是林木模型。(Frics 1974)。Butkin(1972)等人研究表明,林木模型在描述林木之间竞争、死亡、种间竞争的转化和环境对森林生长的影响等方面,是十分有用的一个工具。林分模型,则是用较少的参数,描述林分的大量自然现象。它们所提供的信息数量,足以回答在森林经理上的一些重要关键问题。虽然最早应用于异令林生长预测的模型是林分表预测(Hush等人,1972)但随着时间的推移,一些内容更加详细的模型也相继提出来了
The existing mathematical models for managing heterogeneous forests can be divided into two categories according to the objects they apply: one is the stand model and the other is the forest model. (Frics 1974). Studies by Butkin (1972) and others show that forest models are very useful tools in describing the competition and death among trees, the transformation of interspecific competition and the impact of environment on forest growth. Stand model, is the use of fewer parameters, describing a large number of natural phenomena in the forest. The amount of information they provide is sufficient to answer some of the key issues that matter to forest managers. Although the earliest model used to predict plantation growth was the stand model (Hush et al., 1972), some more elaborate models have been proposed over time