UAV写真測量における多時期計測データを用いた河道管理手法の検討

抄録

Structure-from-Motion photogrammetry (SfM) that determines three-dimensional topography from UAV images has been employed, however this is limited in use for river channel management owing to the lack of topographic data under vegetation cover and so on. The Digital Surface Model (DSM) in the area where vegetation grows from SfM is supposed to fluctuate due to seasonal vegetation change such as fallen leaves and dying down, however it is not quantitatively evaluated. Therefore, in this study, we quantitatively estimated how the value of DSM responds to the seasonal changes of vegetation and investigated the measurement timing of UAV photogrammetry and the method of utilizing data in order to evaluate discharge capacity of river channel.

From the results of the experiments, it was figured out that DSM indicates the position of the height of the surface layer of the vegetation during vegetation bloom season and the position of the height of the middle and lower layers of the vegetation during season for leaves to fall. Moreover, it was understood that it is possible to evaluate the ground surface elevation depending on the timing of measurement, the type of vegetation and its distribution.