[A-HW24] Material transportation and cycling at the land-sea interface: from headwaters to the ocean

[AHW24-20] Simulation of Suspended Sediment yields in forested head-watershed at Ibaraki Prefecture by using SWAT

*Naohiro Imamura¹, Kunyang Wang², Shin-ichi Onodera², Yuta Shimizu³, Masahiro Kobayashi¹, Takanori Shimizu¹, Yoshiki Shinomiya¹, Tatsuya Tsurita⁴, Naoyuki Yamashita¹ (1.Forestry and Forest Products Research Institute, 2.Hiroshima University, 3.National Agriculture and Food Research Organization, 4.Agriculture, Forestry and Fisheries Research Council)

Keywords:Suspended Sediment (SS), SWAT, Forested head-watershed

Forest managements have been increasing all over the Japan recent year. Therefore, predicting the impact of forest operations on sediment yield at forest head-watershed has been more important. However, model simulation research for sediment yields at head-watershed is very rare. This study estimated daily water discharge and Suspended Sediment (SS) yields in forested head-watershed (60 ha) at Ibaraki Prefecture from 2015 through 2018 by using SWAT. As a result, daily hydrographs and SS yields showed relatively high reproduction for observed values (Nash-Sutcliffe efficiency (NSE) showed over 0.66 value). Annual SS yield value was 0.013 tons ha⁻¹. This result means SWAT has a potential for simulating sediment yields at forested head-watershed in Japan.