[H-TT14] HIGH-DEFINITION TOPOGRAPHIC SURFACE DATA FOR CONNECTIVITY IN THE ANTHROPOCENE

[HTT14-P01] Precision Enhancement in Slope Elevation Variation Using UAV Technology in the Absence of GNSS Control Points

*Yu-Shen Hsiao¹, Kuan-Hsiang Fang¹ (1.National Chung Hsing University)

Keywords:UAV, Elevation variation, Coordinate transformation, Remote sensing indicator

We use Unmanned Aerial Vehicle (UAV) technology to generate orthophoto mosaics, Digital Surface Models (DSMs), and 3D point clouds for calculating elevation variations in multi-temporal images. In recent years, UAV technology has been extensively utilized in the field of water and soil conservation, particularly in monitoring slope dynamics over multiple periods. However, challenges arise when calculating elevation variations such as sediment transport in river channels, soil erosion and deposition on slopes, with common issues including: (1) Difficulty in establishing Global Navigation Satellite System (GNSS) control points in mountainous regions; (2) Elevation miscalculation due to river channel flow or slope vegetation. To address these issues, we use coordinate transformation methods, such as 4-parameter, 6-parameter, and 7-parameter transformations, along with multiple remote sensing indicators, including GLI, NGRDI, and NGRDI, to achieve more accurate elevation variation results. This study aims to provide valuable insights for future water and soil conservation practices, enabling more efficient UAV-based monitoring of terrain changes.