Author(s): Tomoko Kyuka; Satomi Yamaguchi; Kazunori Okabe; Yasuyuki Shimizu; Hideto Kon
Linked Author(s): Yasuyuki Shimizu
Keywords: Otofuke River; Record breaking rainfall; Vegetation; Bank erosion
Abstract: Floodplain vegetation is one of the key factors to determine the channel planform dynamics in alluvial systems. In this study, we focused on the range of vegetation variety, especially vegetation disappearance during flood event due to scouring and bank erosion by means of computational analysis targeted on the Otofuke River and subsequent experimental test. The results showed that if vegetation is young and relatively easily flushed away by scouring and bank erosion during flood, it leads to weak points (gaps) of bank strength along main flow channel, resulting in the flow concentration into the gaps, leading to active local bank erosion and lateral channel migration for a short-term more than that of cohesionless, no-vegetated case.