*Maksym Gusyev¹、Yoshito Kikumori¹、Masatoshi Denda²、Hide Toda³、Maki Tsujimura⁴、Koichi Sakakibara³、Uwe Morgenstern⁵、Michael Kilgour Stewart⁵ (1.International Centre for Water Hazard Risk Management (ICHARM), Public Works Research Institute (PWRI), Japan、2.River Restoration Team, Public Works Research Institute (PWRI), Japan、3.Department of Environmental Sciences, Shinshu University, Japan、4.Graduate School of Life and Environmental Sciences, University of Tsukuba, Japan、5.GNS Science, New Zealand)