The area around the estuary of Nanakita river was utterly destroyed by tsunami caused by the 2011 off the Pacific coast of Tohoku Earthquake. Fortunately the communities of Phacelurus latifolius and Rosa rugosa barely survived the tsunami. However, the growth place of the vegetation was completely washed away by the typhoon in September, 2011. The report shows how the vegetative landscape has changed from April to September, 2011 after the tsunami damage and a flooding by the typhoon.
Beginning from April 13th, 2011, the Sendai Science museum, once or twice in a month, researched the plant damage caused by the tsunami of the Pacific Ocean tide Tohoku earthquake mainly in the Gamou and Sendai bay area. The results indicate that the plant damage should be separated into two causes, physical factor and salt ater.
The deciduous trees sustained less damage from salt water. Therefore, it is clear that the damage influenced the trees before they opened their leaves.
The Pine-plantation on seaside sand dunes sustained serious damage caused by the 3.11 tsunami. The old-growth pine trees were fallen in-line in the area. This phenomenon could be an influence on the depth of water caused by a slight unevenness on the ground surface. An aerial photo of alder tree distribution was used to estimate the unevenness. Consequently, it was confirmed that an infinitesimal concavity in the Pine-plantation on seaside sand
dunes let tsunami invade the area and the wave induced the in-line fallen forest.
According to the research on the invasion of the broad-leaved tree species into old-growth Pinus-plantation on seaside sand dunes in Sendai bay area, deciduous trees such as Prunus sp. and Neolitsea sericea invaded the old-growth Pine-plantation on seaside sand dunes. The analysis focusing on the architecture of trees indicates a possibility that the high plasticity of Neolitsea sericea functions effectively.