Pinus nigra biomass estimation with unmanned aerial vehicles (an example of Sivas Cumhuriyet University campus)

Unmanned Aerial Vehicles (UAV) are widely used in various fields nowadays. In forestry, they have been used to estimate parameters such as tree heights, diameter at breast height (DBH), crown area, crown width and etc. In this study, we aim to create a work flow to estimate individual tree heights and relate them to individual DBH and biomass by creating an equation fit for pinus nigra tree species. In order to achieve the study's goal, UAV flights and detailed ground measurements were carried out. To create a reliable foundation for the equation parameters, 394 ground measurement were obtained in order to understand the accuracy of the work flow. Created equation was then carried out on ground measurements of the study area for validation purposes. With the use of this equation, researchers can obtain both individual tree heights and their related DBHs as well, without the need of ground measurements. Validation of tree heights (estimated and ground measured) and DBH (equation estimated and ground measured) yielded a mean error of ±70 cm and ±1.5 cm which corresponds to approximately 8.2% and 7.9% of the average height and DBH, respectively. In terms of biomass, validation of equation estimated and drying processed biomass values yielded a mean error of ±2.08 kg which corresponds approx. 9.95% of the average drying processed biomass values. The workflow presented in this study can aid in both financial and time aspects of researchers' aim to create forest inventories.