2020 Volume 26 Pages 569-572
The 2018 Hokkaido Eastern Iburi Earthquake caused over 6,300 landslides in total, and large amounts of sediment and woody debris were deposited on stream channels and plains. This study focuses on estimating the amount of sediment and woody debris from landslides triggered by this earthquake. First, by comparing LIDER data before and after the earthquake, we estimated that the average landslide depth of the landslide was 1.77 ± 0.63 m. As a result of applying this depth to the shallow landslides in the upper Atsuma River basin, the amount of sediment production amount was 49.4 ± 17.7×106m3. Next, as a result of analyzing the relationship between the detailed forest plot and the landslide data of the Atsuma River basin, the total fallen tree amount was estimated to be approximately 462×103m3.
