Impacts of the Great East Japan Earthquake and tsunami on the tidal flat and Zostera spp. habitats, and the characteristics of tsunami deposit in Miyagi, Japan

2014 Fiscal Year Final Research Report

• Project/Area Number: 24710080
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Environmental technology/Environmental materials
• Research Institution: Ishinomaki Senshu University
• Principal Investigator: TAMAKI Hitoshi 石巻専修大学, 理工学部, 准教授 (30364417)
• Research Collaborator: KOSE Tomohiro 新潟薬科大学, 応用生命科学部, 准教授 ; MURAOKA Daisuke 東北区水産研究所, 浅海生態系, グループ長
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 東日本大震災 / 藻場 / 干潟 / 津波堆積物

Outline of Final Research Achievements

Impacts of the Great East Japan Earthquake and a tsunami event on the tidal flat and Zostera spp. habitats were studied. And we also investigated the characteristics of tsunami deposit in Miyagi. Although Zostera habitats had largely decreased, Zostera caulescens tended to recover slightly when compared to the density of Zostera marina. In the tidal flat, the silt content and sulfide concentration at the sediment tended to increase due to the reduction of the ground level. After the event, the mean density of macrobenthos was reduced by three quarters. Although their density increased in August 2012 as well as before the event, it decreased again by August 2013.
We also performed a restoration effort using the tsunami deposit, because heavy metal contents in the tsunami deposit were lower than those in environmental quality standards. The settlements of Ruditapes philippinarum in the sediment were increased by the addition of tsunami deposit.

Free Research Field

生態工学