Volumetria em povoamentos puros de tachi-branco (Tachigali vulgaris) em diferentes espaçamentos

Abstract

Among the Brazilian native species with commercial potential, the white tachi (Tachigali vulgaris L. Gomes da Silva and H. C. Lima) has a prominent position. This species is a fast-growing tree legume with potential use for energy, recovery of degraded areas, afforestation of parks and highways, use of nobles and component material in cement used in the construction industry. In spite op this known characteristics, studies on this species are incipient, requiring further study on its ecology, silviculture and management. Thus, the objective of this work was to develop volumetric equations for pure white tachi plants, evaluating the effect of initial plant spacing on volume areas. The data used are from a white tachi experiment, implemented in 2010, in the north of the state of Pará. The experiment was conducted under a randomized block design, with three blocks, each with six intervals, T1 (3,0 × 1,5 m); T2 (3,0 × 2,0 m); T3 (3,0 × 2,5 m); T4 (3,0 × 3,0 m); T5 (3,0 × 3,5 m); and T6 (3,0 × 4,0 m). Three trees per treatment in each block and at two ages were absolutely cubed, totaling 108 trees. The most common volumetric models used were used for two different situations: consider each object as a tree and use the equivalent tree diameter as independent variables in the volumetric model. In addition, an equation for estimating the equivalent diameter was proposed. According to the results, it was found that the equivalent diameter promoted more accurate volumetric estimates in relation to the diameter at breast height. In addition, the Schumacher and Hall model was efficient for volume estimation of Tachigali vulgaris, whose planting spacing had no influence on the development of independent volume equations and thus a single equation can be used. The equivalent diameter can be estimated via equation, whose estimates did not influence the volume per unit area.