三陸リアス式海岸の水際におけ る防潮堤と土地利用

摘要

The tsunami that followed the earthquake that occurred in March 11,2011 destroyed almost all the fishing villages along the serrated coast of northeast Japan. The affected prefectures plan to reconstruct and enlarge the sea dike to prevent damage from future tsunamis with financial support from the Japanese Government. However, many people affected by the tsunami oppose the construction of the sea dike, which would have a maximum height of 14.7 m. Since people cannot reside in the lowland along the coast as per the legislation established after the March 2011 tsunami, they chose to migrate to the hills. Therefore, they do not consider it necessary to construct the huge sea dike; they wish to live with the sea and without being separated from it by the sea dike. Moreover, the land subsided due to plate tectonics; it was eroded by the strong current of tsunami, and a new tidal flat and salt marsh appeared in the innermost parts across the bay. Fisheries, which are a major industry of the coastal area, will benefit more by oreservine the brackish wetland as a natural habitat than by constructing the huge sea dike.