Source of Sediment and Seasonal Variation in Particle Size in the Mukawa Coast, Northern Japan

Abstract

To elucidate the seasonal change, spatial distribution of particle size and source of coastal sediment, monitoring and fingerprinting of coastal sediment were conducted in the Mukawa Coast, the Pacific Ocean of Hokkaido, northern Japan. Statistical analysis among the indices of the particle size and the wave and discharge suggested that the seasonal and temporal variation in particle size can be controlled by fine sand dynamics through the interaction between seasonal change of wave and discharge and geographical condition associated with river mouth and port. The source areas of the fine sand were estimated as upstream and midstream of the river watersheds through the fingerprinting technique using natural radionuclides.