抄録
This study examined factors that affected the geographic distribution of shallow landslides caused by typhoon 0310 (Etau) in the Appetsu River basin in the Hidaka region of Hokkaido. We established a 7.5 km2 study area in the basin of the Itarakki River, a tributary of the Appetsu River. Using mainly field surveys, we investigated the properties of shallow landslides and geology and then mapped shallow landslides and geology type. Slope degree, profile curvature, plan curvature, geology type, and forest type were chosen as factors that may influence shallow landslide occurrence. We divided the study area into 10-m grids using geographic information system software and analyzed the relationship between each factor and landslide occurrence in each grid using logistic regression analysis. Landslide probability of steep or concave slope was higher than that of gentle or convex slopes. Plan curvature was more important factor than profile curvature. Some types of geology and forest were significant factors that influence landslide occurrence.
