抄録
Characteristics of coastal forest damage in the Sendai Plain caused by the 2011 off the pacific coast of Tohoku Earthquake Tsunami is that a lot of tree uprooting damages were observed with a part them being washed away all together with the roots. Therefore, conditions that caused tree uprooting have been demonstrated by measuring the depth of ground water beneath the affected area where Pinus densiflora Sieb.et Zucc.and PinusThunbergii Parl grew. Relationship of trunk break and tree uprooting damage with tree size (diameter at breast height) was also examined. At a part with a ground water depth of less than about 1.0 m, trees were uprooted and flown out regardless of their sizes. In contrast, both trunk break and tree uprooting were observed in only smaller number of samples with a diameter at breast height of more than 20 cm. Therefore, we think that it was required to secure adequate depth of ground water by way of filling and regenerate forests filled with thick and robust trees in order to build up coastal forests with higher resistance against tsunami. In consideration of impacts of ground sinking and the like, it was believed the depth of ground water to be secured for filling was required at least 1.5 m.
https://ror.org/044bma518 