[ACG43-P06] The estimation of CO2 flux in subtropical coastal ecosystems using a numerical model
Keywords:Ecosystem model, Subtropical coastal ecosystem, Air-ecosystem CO2 flux, Carbon burial rate, Future prediction
In this study, we developed a new ecosystem model that incorporates the biogeochemical processes of mangroves, tidal flats, seagrass meadows, lagoons, and coral reefs. We estimated CO2 fluxes between air and the ecosystems and carbon burial rates in Yaeyama islands, Japan, which is the model site. In the future prediction, we selected two scenarios of representative concentration pathways, low emission (RCP2.6) and high emission (RCP8.5), adopted in IPCC 5th Assessment Report and compared the model results in 2010 and 2100. The output of HadGEM2-ES from CMIP5 models were used as the boundary data.
Our model results showed that the mangrove absorbed CO2 more than other ecosystems because of direct uptake of CO2 from the air. The maximal carbon burial rate was found in the mangrove. Additionally, the inflowing of open waters affected the air-ecosystem CO2 flux and carbon burial rate near the open boundary. We will also present the result of comparisons between the model results and observed data.