Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Evening Poster

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

[A-CG42] Coastal Ecosystems - 1. Water Cycle and Land-Ocean Interactions

Thu. May 24, 2018 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Ryo Sugimoto(Faculty of Marine Biosciences, Fukui Prefectural University), Jun Shoji(Hiroshima University), Makoto Yamada(龍谷大学経済学部, 共同), Masahiko Fujii(Faculty of Environmental Earth Science)

[ACG42-P03] Carbon transport through groundwater discharge in Kesennuma Bay, Japan

*Ryo Sugimoto1, Toshimi Nakajima1, Isaac R Santos2, Makoto Taniguchi3 (1.Faculty of Marine Biosciences, Fukui Prefectural University, 2.Southern Cross University, 3.Research Institute for Humanity and Nature)

Keywords:Submarine groundwater discharge, pCO2, 222Rn

Submarine groundwater discharge (SGD) is an important source of nutrients, trace metals, and carbon to coastal ecosystem. To quantify this processes in Kesennuma Bay, 24-hours mooring surveys for SGD tracers (Rn and Ra isotopes) and biogeochemical properties (nutrients, dissolved carbon and iron) were conducted during neap and spring tides in summer 2017. In this presentation, we will show results of simultaneous measurements of 222Rn and pCO2. Although pCO2 showed clear diurnal variation according to the photosynthesis/respiration process in both periods, excess CO2 was supplied through significant groundwater discharge during the lowest tide in spring. These data will be used to quantify carbon flux from SGD and emission rate of CO2 to atmosphere.