STUDY OF THE OPTIMAL TIME FOR REPLACEMENT OF Eucalyptus spp. PLANTATIONS – THE CASE OF COSTS REDUCTION

• Autor(a) principal: Souza, Álvaro Nogueira de
• Data de Publicação: 2002
• Outros Autores: Oliveira, Antônio Donizette de, Rezende, José Luiz Pereira de
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Ciência Florestal (Online)
• DOI: 10.5902/198050981706
• Texto Completo: https://periodicos.ufsm.br/cienciaflorestal/article/view/1706
• topic: technological progress; renewal; forest costs.; progresso tecnológico; reforma de Eucalyptus; custos florestais

The objectives of this work were: a) to study the effects of cost reduction on the optimal replacement time of Eucalyptus plantations; b) to determine rotation age, keeping income constant and cost decreasing overtime; c) to verify the efficiency of a mathematical model for modelling  technological progress effects; d) to verify which would be the substitution cicle if the income had been constant since the sixties; and, e) to project substitution time in the future, considering decreasing cost and constant income at today’s values. Data from forest enterprises located in the Cerrado region were used. The Gompertz Function  was employed to calculate timber yield. The economical evaluation method used was the Present Net Worth. The proposed model allowed calculating  technological progress effect on costs in the 1960 - 2000 period and to project the cost values for the 2000 – 2040 period. It was concluded that: a) the rotation, with current values is 7 years; b) maintaining the income  at the sixties levels, the optimal  substitution cycle would be at 6 cuttings; c) the model proved to be efficient for estimates of up 40 years horizon; and, d) the substitution chain showed that the optimal substitution cycle went down along the years, from 6 cuttings in the sixties, 3 in the eighties and 2 currently; the future tendency is to stick with 2 cuttings, reaching 3 cuttings with increase in the coppice yields.