Changes in Erodibility and Eutrophic Components Outflow due to Armoring of Bottom Sediments

Abstract

The objective of this study was to investigate the erosion mechanism of bottom sediments from a viewpoint of consistency changes in armoring process. Additionally, the outflow of eutrophic components from armored bottom sediments was compared with that from non-armored.
Suspended solids in eroding water of bottom sediments higher than 75 % of sand remarkably increased with the increase in shearing stress. After erosion experiments, water content of bottom sediments higher than 75 % of sand was higher than liquid limit. It became clear that high erodibility appeared when water content of bottom sediments was beyond liquid limit. The eutrophic components outflow of armored bottom sediments was similar to that of nonarmored. It follows that the eutrophic components outflow was not affected by increasing sand percentage of bottom sediments, but affected by the concentration of suspended solids.