Otimização do microplanejamento na colheita de madeira em plantios de eucalipto

Abstract

This work proposed the optimization of operational planning variables in the timber harvesting, aiming to subsidize micro-planning, increase of productivity and minimize cost. A method of distribution and sequencing of forest machines was tested. Then, several timber extraction scenarios were evaluated as a function of operational planning variables. Finally, influence of wood pile placement in productivity and cost of timber extraction and forest loading were verified. Study was carried out in a forest company located in Santo Antônio do Paraíso, on Eucalyptus saligna stands submitted to clear cutting at age 10. Research database consists of technical and economic variables of operations, cost of roads, as well as geographic data resources. Harvest compartments were hierarchically grouped by the Ward method, using as measure of dissimilarity the Euclidean distance. Then, minimum route of displacement of the machines was determined by the Kruskal algorithm, for each group formed. Next, five compartments were selected and scenarios were proposed, with simulation in a GIS environment. Minimum cost aggregate between harvest and forest roads was obtained Integer Linear Programming (ILP). Finally, were verified the effect of three distinct wood pile positions on the productivity and costs of timber extraction and forest loading. The process of distribution and sequencing of harvesting operations estimated six harvesters and five forwarders, where subdivided into two groups, allowed the maximization of operational efficiency by 4.86%. The simulation model pointed to better alternatives in detriment to the actual execution observed, reducing the total cost by up to 25.3 %. For different treatments, the standard pile was the most economical for timber extraction and forest loading, with a reduction of 6.08 % in the cubic meter of wood produced.