Estimativa de variáveis dendrométricas utilizando imagens aéreas em plantio de Araucaria angustifolia (Bertol.) Kuntze

Abstract

With the advancement of new technologies applied to forestry practices, the use of remotely piloted aircraft (RPA) has gained traction in discussions related to forest management and inventory techniques. These technologies aim to quantify quantitative data regarding forest stand and plantation characteristics. This study aimed to compare dendrometric variables obtained in the field through traditional forest inventory methods and estimate dendrometric variables acquired through aerial imagery for a planting of Araucaria angustifolia (Bertol.) Kuntze. The field inventory was conducted through five random plots within the plantation, where variables such as diameter at breast height (DBH) for all individuals and heights (h) of dominant trees, representing the largest DBH values within the plots, were collected. For the RPA survey, a flight plan was defined, from which orthomosaics and Digital Surface and Terrain Models (DSM and DTM) were generated. Using the orthomosaic, it was possible to delineate plot areas and define the canopy area (CA) of individuals, while height was calculated using the difference between DSM and DTM. DBH values were generated through mathematical models based on variables h and CA. Subsequently, a paired T-Student statistical test was applied to verify if a significant difference occurred between the two methods of inventory data acquisition (height), one using the traditional method and the other through aerial imagery. According to the analysis, a significant difference was observed between the surveys, as the aerial survey methodology tended to overestimate the values of the variables when compared to the conventional method. Therefore, further studies and techniques are necessary to ensure that the variables obtained through RPA flights can be similar and provide accurate data for inventories conducted in plantations of this species.