Coastal forest damage from the 2011 Tohoku tsunami and related mitigation by fill at Yuriage beach, Miyagi Prefecture, Natori City, Japan

Abstract

The 2011 Tohoku Earthquake and the subsequent tsunami heavily impacted Yuriage beach in Miyagi Prefecture, Natori City, Japan. We investigated tsunami damage as well as the benefits of mitigation to coastal forests caused by fill formed by wasted soil. Three belt transects ( A, B and C) were placed perpendicular to the shoreline extending inland from the shoreline itself. The widths of the coastal forest zones at transects A , B and C were 130.2m, 58.8m and 56.2m, respectively. Transects B and C were located on the back of the fill formed by wasted soil. Transect B was more heavily impacted by the tsunami than transect C. The number of the Japanese black pine flowed by the tsunami in transect C was about 1/15 compared with that in A and B, based on field investigations and interpretation of aerial photographs. Transect C, which was located in the center of the fill formed by wasted soil, had little damage to its coastal forests in comparison with A and B.