2019 年 25 巻 p. 583-588
In the upper reaches of the Aga River, the flood plain has been vegetated and the river bed topography has become single-row alternate bars. Therefore, by cutting trees and excavating the flood plain, the gravel bar with double-row was restored and the flow attacking point was mitigated. The gravel bar has been maintained by disturbance due to small and middle-scale floods. In this paper, the effects of the restoration project are verified from the results of the monitoring survey and the flood flow analysis, and the importance of the small and middle-scale floods for the maintenance of the gravel bar was examined. In addition, we indicated the future direction of the management considering the flood characteristics and the characteristics of meso-scale river bed configuration in order to maintain the gravel bar.
