Assessing the Potential of Macroalgae-Based Carbon Sequestration in Indonesia

Macroalgae are being intensively explored as a nature-based solution to address climate change. Although there are still some uncertainties about recognizing macroalgae in climate mitigation, the research trend on macroalgae carbon potential continues to increase. We collected secondary data, literature reviews, and expert opinions through focus group discussions to estimate the carbon sequestration potential of macroalgae and examine its feasibility in Indonesian climate mitigation. Our analysis shows that the carbon sequestration potential of macroalgae in Indonesia is significant, estimated to range from 351.246-2.526.332 Mg C yr-1, placing macroalgae as the third largest marine carbon store after mangroves and seagrass. In addition, macroalgae have higher CO2 sequestration rates than other blue carbon habitats. Our assessment of the viability of macroalgae in the blue carbon shows that macroalgae meet the critical elements of blue carbon criteria, including carbon sequestration scale, long-term storage, anthropogenic impact, and social or environmental interventions. However, aligning it with other climate mitigation policies is essential for macroalgae to be fully recognized in blue carbon. This preliminary study suggests that macroalgae could be necessary for Indonesia's climate mitigation action.