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Research in optimizing forest management has focused on single-stand problems to derive optimal harvest sequences in terms of residual basal area or residual stand structure for uneven-aged stands, and timing of pre-defined thinning treatments and clearcut harvests for even-aged stands. Recent research results provide various means of numerically deriving optimal management prescriptions for single-stand problems, thus considering all feasible solutions as opposed to considering only pre-defined harvest alternatives. However, forest-level problems involving aggregates of stands with similar management constraints are usually solved by evaluating pre-defined harvest sequences. Forest-level management optimization problems in which individual stands may be assigned to either even-aged or uneven-aged silvicultural systems have not been modelled. A dynamic forest management model is describer: that prescribes silvicultural treatments for stands within a multi-stand management unit. Results of an application of this approach to an Appalachian hardwood forest, comparisons of individual stand and whole forest optimal solutions, and efficiency of the solution algorithm are discussed. / Ph. D.

The methodology and the appropriateness of adapting the linear programming model to the evaluation of timber harvest alternatives of a specific forest enterprise was examined. The use of linear programming to describe a program in which profit is maximum rather than one of several other economic allocation models was justified. The basic model, using 3 percent as the alternative rate, described the alternative thinning and harvesting opportunities for the Seward Forest at Triplett, Virginia. The optimum program had to satisfy the restrictions imposed by scarce resources and by personal management constraints. The solution of the model described a course of action for the forest manager for the next 50 years. The initiation of the optimum plan would result in maximizing total present worth to the fixed resources of the Forest. Changes were made in the constraints on the model to demonstrate their effect upon the combination of activities which comprise the optimum program and the effect of these constraints on present worth. Additional solutions at 6 percent and 10 percent alternative rates were made to demonstrate the change which occurs in the activities that describe the optimum program at successively higher alternative rates. / Master of Science

Orientador: Antonio Carlos Moretti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-26T14:54:10Z (GMT). No. of bitstreams: 1 Gambaro_Andre_M.pdf: 2586966 bytes, checksum: 3a18149e2d94fa07e52e9d0e184015d8 (MD5) Previous issue date: 2015 / Resumo: A gestão florestal é uma área de significativa importância para a indústria e sociedade e traz consigo desafios consideráveis de planejamento de curto e longo prazo onde modelos matemáticos têm sido propostos para apoio das decisões envolvidas. Neste contexto, o presente trabalho busca revisar a literatura em busca de apresentar os principais modelos e sistemas utilizados, em particular os modelos de simulação e de programação linear de tipo I e II para o problema de planejamento florestal de longo prazo. É proposta também para este problema uma abordagem que utiliza a técnica de decomposição de Dantzig-Wolfe e geração de colunas para integrar os aspectos de sistemas de simulação de intervenções florestais com a programação linear. A abordagem explora de perto as estruturas de rede dos subproblemas que são associados ao problema de caminho mínimo e resolvidos via programação dinâmica e programação linear. Por fim testes são realizados com a implementação da abordagem em instâncias do problema e os resultados apresentados / Abstract: The forest management has been of significative importance for industry and society along the years and brings with it considerable long and short term planning challenges where mathematical models have been proposed to support the decisions involved. In this context, this work aims to present a brief review of main models and systems of this area in the literature, particularly linear programming models of the type I and II. It is also proposed the use of Dantzig-Wolfe decomposition and column generation techniques for the long term forest planning problem in a way to approximate and integrate the simulation models with linear programming techniques. This method explores the network structure of the sub-problems which are close related to the shortest path problem and solved by dynamic programming and linear programming. Finally, tests with these techniques are performed for some instances of the problem and results are presented / Mestrado / Matematica Aplicada / Mestre em Matemática Aplicada