MODEL-INDUCED COMPARATIVE STUDY OF ALB AND UAV-BORNE GREEN LIDAR SYSTEMS ON VEGETATED LOWER ASAHI RIVER ASSESSMENT IN JAPAN

Abstract

 This study demonstrates the accuracy of vegetated lower Asahi River surveying using both the improved airborne LiDAR topo-bathymetry (ALB) and newly launched unmanned aerial vehicle (UAV)-borne green LiDAR system (GLS), with comparisons among systems-derived, depth-averaged numerically simulated, field- and sensor-based data. This report also examined the applicability of both systems data for low-water flow simulations considering vegetation effects, which enables us to select the most feasible LiDAR-based technique for developing a novel hydrodynamic flow model. Results on topo-bathymetry and vegetation assessment revealed that both systems data were almost identical to the field observations, with an outperformed accuracy of a few dozen centimeters. Based on overall aspects taking account of high spatial resolution aerial image and shortcoming to deep-water, it can be inferred that the compact GLS would be a cost-effective tool worldwide for shallow vegetated rivers management measures after further studies.