Abstract
Recently, the lack of discharge capacity due to sediment deposition and reduction of crop yields of natural Enteromorpha prolifera become problems in the downstream area of Shimanto River. As the results of consideration of relation between sediment transportation and river bed form, the main reason of sediment deposition was increase of sediment supply after the gravel quarrying prohibition, so this tendency is expected to continue into the future. Moreover, variation of sediment supply is found to be affecting the range of riverbed height where Enteromorpha prolifera can growth. Therefore, appropriate location was selected from the experimental results using movable bed, riverbed was formed at a height suitable for the growth of the Enteromopha prolifera. Next year, new vegetation area has been comfirmed.
