This study aimed to test the method of multi-criteria analysis, in the platform of the Geographic Information System (GIS), to perform mapping in levels of suitability for the mechanized harvesting of eucalyptus forests. The study was carried out using eucalyptus stands for cellulose production in the State of Minas Gerais, Brazil. The main factors that influenced the mechanized forest harvesting were determined, as well as the technical and environmental constraints. The quantitative factors (declivity, productivity of the plots, volume per tree, age of planting and number of trees per hectare) were standardized using fuzzy logic. To combine the factors, weights for each of them were established through the AHP (Analytic Hierarchy Process) technique. From these weights, Weighted Linear Combination (WLC) was performed and a map of suitability for mechanized forest harvesting was generated. The mapping process allowed to classify the forest area into five suitability classes: very low (0.2%); low (3.3%); average (15.2%); high (53.0%) and very high (28.3%). The declivity factor was the criterion that most influenced the spatialization in the areas of suitability for forest harvesting with the harvester. The method of multi-criteria analysis has been shown to be an efficient tool to create maps of suitability for the operation with the harvester and to support wood harvest planning by identifying areas that tend to have lower or higher productivity.

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Thermo-mechanical densification modifies wood to produce a more dense and resistant lignocellulosic material and may degrade extractives that contribute to the increased susceptibility of wood to attack by xylophagous organisms. This study evaluated the efficiency of tannin extracts of Acacia mearnsii in the treatment of thermo-mechanical densified pine wood in relation to physical, mechanical, and biological resistance (Cryptotermes brevis) properties. Pinus elliottii samples were pretreated with oxalic acid in a Parr reactor, then treated by diffusion in tannin solutions at concentrations 5, 10, and 15%, and finally hot pressed. The apparent density of the modified wood was 87.8% greater than that of the in natura wood (control) with tannins at 15%. The mechanical strength increased, especially the parallel compressive strength, which had an average increase of 169% for the wood with tannins at 10 and 15%, compared with the in natura wood. There was an increase in termite mortality and a reduction in damage for the modified wood treated with 15% tannins, obtaining the best results in mechanical and biological resistance and for the physical parameters. Thermal densification pine wood and preserved with tannin extractives proved to be a potential alternative as a high performance material.

Performance indicators are tools capable of exposing measurable characteristics and generating relevant information on forest operations, thus being considered pillars for managers to make agile and assertive decisions. Forest extraction with a forwarder must be improved, understanding the factors that affect the costs of this machine, such as productivity (PR), fuel consumption (FC), operational efficiency (OE), and quality of operation. Thus, the objective of this study was to evaluate the implementation of the Overall Efficiency of Forest Machines (OEFM) indicator in the management of forest extraction data using forwarders. Data were collected during forest harvesting from five operating fleets, in commercial eucalypt plantations, in full-tree and coppice regimes, in the states of Bahia and Espírito Santo. The indicator was expressed as a percentage calculated by OEFM = ( ( 4 ∗ PR ) + ( 3 ∗ FC ) + ( 3 ∗ OE ) ) / 10. The performance of the machines was evaluated by a stochastic model of dynamic simulation of systems in eight scenarios, proposing improvement for the average individual volume harvested, fuel consumption, and mechanical or operational stops. Analyzes were performed using PowerSim Studio 9 software. The OEFM of two fleets was higher than the established target of 95.17%, with 95.72% and 97.44%. The OEFM indicator proved to be useful in the management of forest extraction with adequate and easy-to-understand information from a large amount and variety of data. The stochastic simulation model was efficient to study the impact on the global efficiency and the flow of wood extraction by the forwarder.

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