NATIONWIDE ESTIMATE OF THE ANNUAL UPTAKE OF ATMOSPHERIC CARBON DIOXIDE BY SHALLOW COASTAL ECOSYSTEMS IN JAPAN

Abstract

 The role of shallow coastal ecosystems in mitigating climate change is drawing the attention of researchers, policymakers, and citizens. However, to date there has been no nationwide estimate of atmospheric carbon dioxide (CO₂) uptake and carbon storage by shallow coastal ecosystems in Japan. In this study, in accordance with Intergovernmental Panel on Climate Change guidelines, we defined the uptake/emission rate of atmospheric CO₂ by an ecosystem as the rate of change in its carbon stock. We then estimated the potential CO₂ sink of shallow coastal ecosystems throughout Japan. We estimated the present nationwide potential carbon sink to be 1.32 million tons of CO₂/year, with an upper limit of 4.04 million tons of CO₂/year. Based on this estimate, it may help to include shallow coastal ecosystems as a new CO₂ sink under Japanese law and to incorporate them into existing marine environmental policies and frameworks.