Characteristics of Vegetation Recruitment on Floodplains after the 2015 Large Flood in Kinugawa River Observed by UAV Measurement
Abstract
This study aims to evaluate the characteristics of vegetation recruitment after the large flood in Kinugawa River, Japan, owing to the heavy rainfall in September 9-10, 2015. The flood occurred was bought much damage in Kinugawa River. In order to investigate the influence of this flood to the channel geomorphology and vegetation states in Kinugawa River, several floodplains and sand bars were observed using an unmanned aerial vehicle (UAV) in both October, 2015 and June, 2016. Orthochromatic images obtained in the two UAV measurements were overlaid and analyzed by a geographic information system (GIS). The results showed that the land cover changes on the floodplains and sand bars were classified into four patterns including the changes from the bare surface to the vegetation covered one. Then, relationships between the land cover changes, the river bed friction calculated by a numerical simulation, and the relative height from the water surface were examined. The results demonstrated that the vegetation on the floodplains could be destroyed when the friction velocity became larger than 0.1m/s, and also that it could re-enter on the floodplains if the relative height was higher than 2-3m.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFMEP51B0894I
- Keywords:
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- 1813 Eco-hydrology;
- HYDROLOGYDE: 1820 Floodplain dynamics;
- HYDROLOGYDE: 1825 Geomorphology: fluvial;
- HYDROLOGYDE: 1879 Watershed;
- HYDROLOGY