Criterion Dendrometer as a non-destructive method for dendrometric estimations of native species in Western Amazon

Abstract

The use of non-destructive approach for measurement in native environments is still a challenge given the ecology of natural forests. In this sense, the present study aimed to verify the accuracy of the Criterion RD1000® optical dendrometer in the diametric and volumetric estimates of native species in a forest concession area, in Western Amazon. A total of 41 trees were measured at the FMU (Forest Management Unit) III, Flona (National Forest) of Jamari, Rondônia, Brazil, by non-destructive approach (standing tree), using Criterion RD1000® optical dendrometers (indirect measurements), and by destructive approach (felled tree), using a taper and a caliper (indirect measurements). Diameter measurements were made along the commercial trunk every two meters from 1.30 m of the soil (DBH) by Smalian, and the volume was calculated by height classes and for all commercial trunk. The variables were compared by means tests, residue graphs and bias analysis, mean absolute differences and standard deviations of differences. Statistical differences were obtained for heights >13,30 m and for the whole commercial trunk. For class and commercial volumes there was no difference between the tree volume determination approaches, however, there was a tendency to overestimate. Therefore, the non-destructive approach using Criterion RD1000® is presented as an alternative for the tree volume determination, nevertheless, the observed tendencies, in greater heights, reflect the limitations of trunk visualization and the device operation.