This study integrates pre-landslide high-resolution digital elevation model (DEM), digital surface model (DSM) produced using post-landslide drone photography, and geomorphometric analysis to explore the effectiveness of landslide interpretation and fast assessment of geomorphic change. In this study, the large-scale landslide that occurred in Hongye Village, Taitung County in Eastern Taiwan, on September 15, 2016, was investigated. We combined both the microtopography features from the DEM and canopy openness in the DSM to establish an assessment procedure for landslide hotspot extraction. Drone photography and three-dimensional modeling techniques were used to measure the sediment transportation process and conduct postdisaster influence area mapping. The results showed that the landslide area, mean sliding depth, and volume of the landslide in Hongye Village were approximately 4.5 ha, 5.1 m, and 22.8·104 m3, respectively. The runout distance of the initial landslide was 960 m and increased to 1.23 km when the landslide transformed into debris flow in the village. Field validation indicated that the landslideprone
area and subsidence features on the forest canopy could be recognized using a sky-view factor relief and local
relief model. Moreover, a complete landslide susceptibility assessment approach suitable for the catchment scale is
presented.
Key Words: landslide, geomorphometric analysis, SVF relief map, local relief model, UAV.