Comparison of unmanned aerial vehicle (UAV) and DEMNAS in landslide mapping in the Lembang Fault area, Indonesia

The Lembang Fault area has a high potential for landslides due to its location in an active structural zone that shifts annually. The fault movement causes ground displacement, making it important to study landslide potential. Unmanned Aerial Vehicle (UAV) technology can produce Digital Terrain Model (DTM) products with a spatial resolution of 6 cm. This study aims to compare DTM and DEMNAS products in landslide mapping within the Lembang Fault area, West Java Province, Indonesia. The method employed in this research is the Analytic Hierarchy Process (AHP) with variables including slope, aspect, curvature, lineament density, drainage density, Topographic Wetness Index (TWI), rainfall, and lithology. The analysis results show that the Root Mean Square Error (RMSE) of the DTM product is 0.902, indicating that the UAV data acquisition provides better accuracy in landslide mapping compared to the DEMNAS product with an RMSE of 1.592. Although the landslide maps produced from DTM and DEMNAS share similar patterns, the area classifications differ due to their varying spatial resolutions. Both products are equally effective in mapping landslides in the Lembang Fault area, as they both exhibit good RMSE values in the analysis.