*Le Dang^1,2、Hiroshi ISHIDAIRA¹、Phung Ky Nguyen³、Kazuyoshi SOUMA¹、Jun MAGOME¹、Bay Thi Nguyen⁴ (1.Interdisciplinary Centre for River Basin Environment, University of Yamanashi,、2.Faculty of Environment, University of Science, Vietnam National University Ho Chi Minh City, Ho Chi Minh City, Vietnam、3.Thu Duc People's Committee, Ho Chi Minh City, Vietnam、4.Faculty of Civil Engineering, University of Technology, Vietnam National University Ho Chi Minh City, Ho Chi Minh City, Vietnam)