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Brazilian Savanna Height Estimation Using UAV Photogrammetry

Unmanned aerial vehicles (UAVs) have been advancing in precision and cost-benefit for remote sensing studies, including height and biomass estimations. This article presents a preliminary experiment to explore UAV photogrammetry to estimate canopy height in savanna and grassland phytophysiognomies in the Brazilian Cerrado biome. For this purpose, it was generated dense cloud points to obtain digital terrain and surface models used to calculate the canopy height. The spatial distribution of canopy height ranged from 0 to 4 meters, in which the most values were under 50 cm, commonly found in grasslands and observed in vegetation regrowth of post-fire event in savanna areas.