It’s time to broaden what we consider a ‘blue carbon ecosystem’

Marine ecosystems are important in mitigating rising atmospheric CO2 because of their capacity to store significant quantities of carbon (called blue carbon). To date, three key blue carbon ecosystems have been recognised (seagrass meadows, mangrove forests, tidal marshes), however, evidence is emerging that other ecosystems may also be important. Here, we use meta-analysis of 253 research publications to investigating the role of other marine ecosystems in blue carbon. At present, mud / tidal flats, shallow sediments / fjords, some components of coral reef systems (e.g. lagoons) and coralline algal beds should also be considered important for blue carbon burial.