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在森林经营管理中,林分水平决策的重要性随着对森林资源的日益需求而更加突出。对美国整个混交林分来说,由于各树种组之间在生长率、对间伐的反应以及大小级等方面都存在着明显的差异,其收获决策是非常复杂的。过去用于单一树种收获的优化方法有边际分析(Chappelle和Nelson1964)、变分法(Naslund1969,Schreuder1974),动态规划(Amidon和Akin1968,Chen等1980,Brodie和Kao1979,Riitters等1982)和非线性规划(Kao和Brodie1980)。然而,这些研究都未曾考虑到单一树种组明显的大小级差异。在这一点上,可将时间上的最优密度问题系统地阐述为非线性整数规划问题。随机搜索法可用于评估现实同龄混交林分最优的间伐体制与轮伐期。本文
In the forest management, the importance of decision-making at the stand level becomes more prominent with the increasing demand for forest resources. For the entire mixed stand in the United States, harvest decisions can be quite complicated because of significant differences in growth rates, responses to thinning, and size, among tree species. In the past, optimization methods for harvesting single trees were marginal (Chappelle and Nelson 1964), variational (Naslund 1969, Schreuder 1974), dynamic (Amidon and Akin 1968, Chen et al 1980, Brodie and Kao 1979, Riitters et al 1982) and nonlinear programming (Kao and Brodie 1980). However, none of these studies considered the obvious size-level differences among single tree species. At this point, the optimal temporal density problem can be systematically described as a non-linear integer programming problem. The stochastic search method can be used to evaluate the optimal thinning system and rotation period of the mixed forest with same age. This article