Influência da disposição dos feixes de árvores em diferentes angulações na produtividade e custos de um sistema de árvores inteiras

Abstract

The objective of this work was to evaluate the influence of different angulations of the tree bunching on the time, productivity and costs of a full tree harvesting system composed by a feller-buncher and a skidder. The bunches were placed at 45°, 90°, 135° and 180° in relation to the alignment of the forest plantation in which they also represented the necessary angulation for the rotation of the feller-buncher for the formation of the bunches. A work time study was performed in order to obtain the productive time and consequently to estimate productivity and costs of each operation. The feller-buncher’s productivity was influenced by the angulations worked and the number of trees per cycle. The feller-buncher presented higher productivities (105.70 m3 h-1) and lower costs (1.80 USD m-3) when operated at 45°. The skidder´s productivity was not influenced by the different angulations of the tree bunching. However it was related with the skidding distance, number of trees per cycle, and speed. The skidder´s productivity was estimated at 181.90 m3 h-1 with a cost of 0.75 USD m-3 when the skidder was operated at 5 km h-1 and 216.50 m3 h-1 with a cost of 0.63 USD m-3 when operated at 7 km h-1.