Environment monitoring on Coastal Sediment by using digital camera images in Narugashima at Awaji Island

Abstract

This paper proposes a new method of the environment monitoring on coastal sediment. To clarify the temporal-spatial variation of median grain size and effect on coastal vegetation, we applied the method for determining grain size from digital camera images of sediment proposed by Rubin to the sediment at the sandy beach in the Narugashima Island which is located at the mouth of Osaka bay, Japan. We also applied EOF (empirical function) analysis to the temporal-spatial data of median grain size which was obtained by above method and extracted the principal component which rules sediment dynamics. From the results of estimation of the amount of wind-blown sand, the sediment tends to move in north- south direction in summer season and in east-west direction in winter one, respectively.