Abstract
In this article we introduce a new method for forest management inventories especially suitable for highly-valued timber where the precise estimation of stem parameters (diameter, form, and tapper) plays the key role for market purposes. The unmanned aerial system (UAS)-based photogrammetry is combined with terrestrial photogrammetry executed by walking inside the stand and the individual tree parameters are estimated. We compare two automatic methods for processing of the point clouds and the delineation of stem circumference at breast height. The error of the diameter estimation was observed to be under 1 cm root mean square error (RMSE) and the height estimation error was 1 m. Apart from the mentioned accuracy, the main advantage of the proposed work is shorter time demand for field measurement; we could complete both inventories of 1 hectare forest stand in less than 2 h of field work.
Highlights
IntroductionIncreasing demands for sustainable forestry require highly precise and fast forest inventories
Increasing demands for sustainable forestry require highly precise and fast forest inventories.Tree height and diameter at breast height (DBH) are the most important parameters in taking forest inventories
Based on the comparison of geodetic surveys, we found out that terrestrial photogrammetry (TP)-based tree positions reached the positional accuracy with root mean square error (RMSE) lower than 0.5 m with maximum of almost 1 m (Table 3)
Summary
Increasing demands for sustainable forestry require highly precise and fast forest inventories. Tree height and diameter at breast height (DBH) are the most important parameters in taking forest inventories. DBH is usually measured manually with a caliper or a measuring tape and it is recorded together with species during field inventories [1]. Tree height is usually measured by a height measuring instrument based on angle and distance measurements. The spatial information (horizontal structure of stand or tree positions) is difficult to obtain, it represents important information regarding the forest inventory itself (the stem density) as well as for studies of distance-dependent growth and dynamics of trees and stands [2]. Manual inventory methods for collecting forest information used nowadays are labor cost- and time-demanding and there is a need to find alternative methods.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
