Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Oral

A (Atmospheric and Hydrospheric Sciences) » A-CG Complex & General

[A-CG43] Coastal Ecosystems - 2. Coral reefs, seagrass and macroalgal beds, and mangroves

Thu. May 24, 2018 1:45 PM - 3:15 PM 201B (2F International Conference Hall, Makuhari Messe)

convener:Toshihiro Miyajima(Marine Biogeochemistry Group, Division of Ocean-Earth System Science, Atmosphere and Ocean Research Institute, The University of Tokyo), Yu Umezawa(Tokyo University of Agriculture and Technology), Atsushi Watanabe(東京工業大学 環境・社会理工学院, 共同), Tomihiko Higuchi(Atmosphere and Ocean Research Institute, The University of Tokyo), Chairperson:Miyajima Toshihiro(The University of Tokyo), Umezawa Yu(Tokyo University of Agriculture and Technology)

3:00 PM - 3:15 PM

[ACG43-05] Depositional environment change and the subsequent habitat relocation affect organic carbon accumulation rate in vegetated coastal ecosystems

*Kenta Watanabe1, Koji Seike2, Rumiko Kajihara3, Tatsuki Tokoro1, Kazufumi Tada1, Shigeru Montani4, Tomohiro Kuwae1 (1.Port and Airport Research Institute, 2.Geological Survey of Japan, AIST, 3.Civil Engineering Research Institute for Cold Region, 4.Hokkaido University)

Keywords:Seagrass meadows, Saltmarshes, Carbon storage, Isotopic analyses, Age-depth modelling

Vegetated coastal ecosystems store substantial amounts of organic carbon (Corg), and the conservation and restoration of these habitats are considered as important measures for mitigating climate change. Although various geophysical and biogeochemical factors control Corg storage in the sediment of these habitats, how spatiotemporal variations in the depositional environment (e.g., relative sea-level change, geological settings, habitat type) affect Corg accumulation rate is uncertain. In this study, we showed that depositional environment changes and the subsequent habitat relocation regulate Corg accumulation rate in boreal contiguous seagrass-saltmarsh habitats by using the historical depositional records. In particular, the Corg accumulation rate was accelerated with relative sea-level rise which would be driven by post-seismic land subsidence in this region. Our findings provide historical analogues for the future impact of sea-level change on Corg accumulation rate in vegetated coastal ecosystems.