Landslide susceptibility models of National Forest Areas in Taiwan were established in this study. A landslide susceptibility index corresponding to a landslide ratio larger than 5% was selected as a threshold value. The
difference between the intrinsic landslide susceptibility index and the threshold value in each grid was used to estimate rainfall threshold values for shallow landslide warnings. The rainfall threshold values for shallow landslide warnings in most grids were slightly larger than those for slopeland disaster warnings and smaller than those for debris flow warnings. These results were rational. The rainfall threshold map estimated using this model exhibited a desirable spatial resolution and could be a basis for a more precise slopeland early warning system.
Key Words: Shallow landslide, landslide susceptibility, early warning model, National Forest Area.