Promises and uncertainties in remotely sensed riverine hydro-environmental attributes: Field testing of novel approaches to unmanned aerial vehicle-borne lidar and imaging velocimetry
Promises and uncertainties in remotely sensed riverine hydro-environmental attributes: Field testing of novel approaches to unmanned aerial vehicle-borne lidar and imaging velocimetry
复制标题
遥感河流水文环境属性的前景和不确定性:无人机载激光雷达和成像测速新方法的现场测试
DOI:
10.1002/rra.4042
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发表时间:
2022
影响因子:
2.2
通讯作者:
Md Touhidul Islam;Keisuke Yoshida;Satoshi Nishiyama;Koichi Sakai;Shin Adachi;Shijun Pan
中科院分区:
文献类型:
--
作者:
小柳颯輝;瓜生大地;熊倉俊郎;中井専人;安達聖;鈴木紘一;山崎正喜;斎藤隆幸;山倉祐也;Md Touhidul Islam;Keisuke Yoshida;Satoshi Nishiyama;Koichi Sakai;Shin Adachi;Shijun Pan
Recent advancements in remotely sensed techniques have markedly expanded data acquisition potential in riverine studies, but the techniques' applicability must be validated and improved because of uncertainties associated with diverse field conditions. This study is the first experimental evidence of using a newly designed unmanned aerial vehicle (UAV)‐borne green lidar system (GLS) and deep learning‐automated space–time image velocimetry (STIV) for remote investigation of hydraulic and vegetation quantities of the gravel‐bed Asahi River in Okayama Prefecture, Japan. In addition to identifying bed deformation in waters shallower than 2 m, the GLS point clouds characterized the submerged infrastructure with block detailing patterns, thereby identifying positional displacement and severely damaged parts. This paper also presents a noncontact method of estimating incremental river discharge. Compared to benchmarked flow model estimates, remotely sensed discharges for three transects covering shallower, deeper, and partially submerged woody vegetation areas were overestimated by 1–11%, with 4% underestimation for another cross‐section. The STIV analysis also showed complicated flow patterns that were reasonably confirmed by flow vectors from depth‐averaged modeling. Ultimately, depth‐averaged flow model estimates validated hydraulic parameters derived remotely from GLS and STIV, and vice versa. In addition to approximating vegetation growth rates, the study using GLS attributes accurately identified riparian vegetation types as herbaceous (70%), woody (86%), and bamboo groves (65%). Finally, our findings provide insight into the management of shallow clear‐flowing vegetated rivers and remote sensing of streamflow to validate hydrodynamic‐numerical methods.