Abstract
High-accuracy bottom surveys by using the RTK-GPS and the ADCP were applied to Nakatsu Intertidal Flat regionally and the sediment discharge from Yamakuni River were estimated by using the data of turbidity meter and the Ashida-Michiue equation. Sediment budget from Yamakuni River to Nakatsu Intertidal Flat was calculated in order to investigate the mechanism of erosion/deposition of the flat. From the long-term data of erosion/deposition of the flat, deposition due to the flood and ordinal erosion could be seen. From the estimation of sediment budget, it was suggested that effects of longshore sediment transport due to mud and sand could not be ignored. From the multivariable analysis of long-term erosion/deposition data, the prediction equation of erosion/deposition of the flat was acquired. It was effected by the precipitation for deposition, the wave height for erosion and the constant value for deposition.
