This paper describes application of airborne LiDAR bathymetry (ALB) with near-infrared and green pulsed lasers for gathering distributed vegetation conditions and topo-bathymetric data for rivers. For the lower Asahi River of Okayama Prefecture in Japan, the ALB data validity was verified using field observation data. This study also examined the applicability of ALB data for numerical simulations of the lower Asahi River flooding in early July 2018 in Japan, comparing simulated and observed data. Results demonstrated that the methodology for this study works well for parameterization of distributed vegetation on a reach scale. This study also applied numerical tests to investigate the effects of vegetation establishment on flood control plans for the lower Asahi River using parameters validated for flood flow simulations. Results demonstrate that the predicted water level markedly exceeds the high water level because of thick vegetation presently established along few-kilometer-long upstream sections of the targeted river reach. Therefore, we conclude that the present findings can support cost-effective management tasks for vegetated rivers.

本文描述了机载 LiDAR 测深 (ALB) 与近红外和绿光脉冲激光器在收集分布式植被条件和河流地形测深数据方面的应用。对于日本冈山县旭川下游，利用野外观测数据验证了ALB数据的有效性。本研究还检验了 ALB 数据对 2018 年 7 月上旬日本旭川下游洪水数值模拟的适用性，比较了模拟数据和观测数据。结果表明，本研究的方法适用于范围尺度上分布式植被的参数化。本研究还应用数值试验，使用经过验证的洪水流量模拟参数，研究植被建立对旭川下游防洪计划的影响。结果表明，由于目前沿目标河段几公里长的上游段建立了茂密的植被，预测的水位明显超过了高水位。因此，我们得出结论，目前的研究结果可以支持植被河流的成本效益管理任务。