非線形写像法による航空レーザ測量データの幾何補正とそれに基づく2014年広島豪雨災害での崩壊土砂量の推定

抄録

In order to accurately estimate soil volume in debris flow areas, nonlinear mapping technique is applied to multitemporal Digital Elevation Models (DEMs) derived from LiDAR data observed before and after the 2014 Hiroshima rainstorm. Geometric distortions between the pre- and post-event DEMs are remarkably reduced by the nonlinear mapping. The erosion and deposition volumes in the debris flow areas are estimated by the elevation change between the DEMs. The result shows that the soils of approximately 700,000 cubic meters are mobilized in the rainstorm. The multi-temporal results of the soil volume estimation quantitatively reveal the volumes removed after the disaster.