2026 Volume 63 Issue 2 Pages 43-49
Recognition and mapping of landslide topography in Japan began with a prototype landslide topographic distribution map of the Hokusho area in Nagasaki Prefecture. After some trial and error, it became an institutional project of the National Research Institute for Earth Disaster Prevention, and its nationwide publication was reported at the Japan Landslide Society (2013). During this period, its position was substaintially confirmed in the” Act on Sediment Disaster Countermeasures for Sediment Disaster Prone Area (commonly known as the ”Sediment Disaster Prevention Act”) revised in 2000. This was backed by discussions and considerations based on aerial photo interpretation and field investigation. The viewpoint of the potential of re-activity risk among the landslide topographic area was required. The AHP evaluation approach was applied to this method, and it has been progressing in various fields. In this report, an overview of this development is presented, especially a review of “when, who, and how it was conceived,” and how the accumulation of ideas and awareness gained from this process will lead to the development of future slope hazard recognition and evaluation axes.
