DETERMINAÇÃO DE VARIÁVEIS DENDROMÉTRICAS A PARTIR DE FOTOGRAFIAS TERRESTRES EM FLORESTAS URBANAS

Abstract

The study aimed to evaluate the use of Terrestrial Photogrammetry in estimating heights and diameters along the stem in standing trees of Araucaria angustifolia. Were selected 50 trees, located in São José dos Pinhais, ranging height from 12 to 20 meter. In measuring the dendrometric variables (height and diameter) along the stem, we used the total station and tree caliper. To observe the images locations measured in the trees were marked with white along the stem. From a tripod and a 12 Megapixel digital camera, the photos were taken at different distances depending on the total height. The tripod was leveled to the ground and the trees taken one by one centered in the image. After collecting data in the field, the images were selected and submitted for verification of software in pixels. Three different terrestrial photogrammetry methods called: Scale / Photography, Mira Topographic and Single-image Photogrammetry. The diameters along the stem measured with calipers and estimated by the three methods were statistically compared. Volume equations and taper functions were fitted to the diameters obtained by caliper and by tested methods to verify the feasibility of the determinations performed with the photogrammetric methods proposed. The results showed that only the diameters measured by Single-image Photogrammetry were statistically identical to the diameters measured with tree caliper. Moreover, no significant differences between treatments for the variable height, showing that the methods are equals. The volume equation and taper function adjusted with diameters generated by Single-image Photogrammetry method had similar performance to the equations fitted to the data of diameters measured with calipers. It was concluded that the Single-image Photogrammetry method showed promising results for the scaling of standing trees in urban forestry.