Author(s): I. Fujita; Y. Terada; G. Kumano; K. Asami; Y. Watanabe
Linked Author(s): Ichiro FUJITA
Keywords: Grain Size Distribution; Cobble Bar; Image Analysis; Multi-copter; BASEGRAIN
Abstract: At a bend of a river, especially in the upstream mountainous region, complex sediment and hydraulic phenomena are taking place and it is important to quantitatively evaluate the phenomena and to predict accurately the sedimentation of a bar developed there. The study area of the Ibo River investigated in this study is classified as one of such a location and a famous vegetation of extinction called‘Anaphalis margaritacea subsp. yedoensis’ (‘Kawarahahako’in Japanese) can be found in the bar area. Since the survival of the vegetation is directly related to the transport of sediment or bed variation of the bar area mainly composed of cobbles, detailed investigation of the sediment components is indispensable for a better understanding of the phenomenon. In this research, we successfully took aerial photographs of the target site by using a multi-copter before and after several floods and compared the grain size distributions by an image analysis.
Year: 2014