Cubagem de árvores em pé pelo método da altura relativa

Abstract

In order to quantify wood multiproducts, besides measuring DAP and total height of inventory parcels, it is necessary to count on volume equations or stem form obtained from data of sample of upper stem diameter measurement. The trees are usually, abated at different places of the inventoried forest area. This may cause inventory bias, because stem form varies markedly even among trees. A possible solution to this problem is to use methodologies that link the upper stem diameter measurement to the measurement of the inventoried parcels. This happen because, given that the trees are distributed in the inventoried area it is possible to obtain stem form of trees better representative than the usual upper stem diameter measurement allowing, therefore, the generation of more reliable equations. The objective of this work was to develop a coherent and reliable methodology for this purpose, using different geometric solids to characterize the stem form of standing trees, measuring only few diameters. As a case study, it was used data of the upper stem diameter measurement of abated trees of a Eucalyptus grandis x Eucalyptus urophylla hybrid plantation located in Northeast of Bahia State. The developed procedures can be adopted in the simulation of the upper stem diameter measurement of standing trees, mainly if the trees are located inside the inventory parcels, requiring only the measurement of two diameters between 1,3 m and the total height. This developed procedure is a completely new methodology and may be called “method of the relative height with two diameters”. The use of this methodology allowed better predictions of stem form and commercial volume if compared to the current version of the method of the relative height.