COMPARISON OF ABSOLUTE VOLUME CALCULATION METHODS WITH WATER-DISPLACEMENT TECHNIQUE FOR Mimosa scabrella Bentham

Abstract

The observed volumes obtained by several volume calculation methods for the bole and sections of the bole of Mimosa scabrella trees were compared with theirs respective true volumes obtained by measurements in xylometer (water-displacement technique). Fifty four sample trees were felled and measured into several municipal districts of the Curitiba Metropolitan Region, in the Paraná State. The sample trees presented DBH from 7,2 to 29,5cm and were grouped in 4 DBH classes. The treatments statistically analysed were the xylometer (control); four absolute volume calculation procedures (Smalian, Huber, Newton and Centroid), each one with three different section lengths (1m, 2m and 4m); the four DBH classes configured the blocks for the statistical analysis. All the treatments presented significant statistic difference related to the xylometer.Amongst the absolute volume calculation procedures the Huber’s formula seems to be the most accurate, although having presented significant statistic difference related to the true volume.