Evaluating the potential of digital twin derived from UAV imagery in vegetation monitoring of downtown streams

초록

Downtown streams flowing through city centers are very narrow (less than 10 m wide) while distributed over long distances (at least more than 10 km). Taking aerial photos targeting downtown streams from a manned aircraft is virtually impossible because low-altitude flights are not permitted over densely populated city centers. However, Unmanned Aerial Vehicle (UAV) images taken at very low altitudes were able to explore area-wide vegetation distribution patterns along the downtown streams; these could not have been obtained from traditional field investigations. The structure from motion (SfM) was applied to build the UAV digital twin with imagery collected from diverse locations and imaging sensors on August 1, 2021. This study demonstrates the potential of digital twins derived from UAV imagery as a means of supplementing traditional field surveys in monitoring vegetation in downtown streams. Furthermore, this study verified that the digital twin was able to accommodate, quantitatively, the in-situ vegetation survey checklist (shape, size, height, tone, pattern, and community) proposed by Braun-Blanquet, in downtown streams from different points of view and angles, as well as spectral characteristics for the area-wide section of a downtown stream. This research output could be a valuable reference for the potential of digital twins derived from UAV imagery in vegetation surveys of downtown streams.

키워드