Resolving the missing carbon sink in blue carbon ecosystems: Oceanic outwelling

Coastal vegetated ecosystems (mangrove wetlands, salt marshes, seagrass beds and macroalgae/kelp forests) are hotspots in the global carbon cycle. Even though they cover a small area, they are large carbon reservoirs being rapidly destroyed.

Preserving these blue carbon habitats has been touted as an effective approach to sequester carbon, mitigate climate change and achieve sustainable development goals.

This project will assess if the sequestration capacity of blue carbon systems has been underestimated because we have focused on soils rather than the oceans as the ultimate, long term carbon sink.

This project will build detailed, comparative carbon budgets from source to sink across the continental shelf off four blue carbon systems.

I will use state-of-the-art geochemical approaches to quantify the source, transformations and the ultimate fate of blue carbon.

This research will close a significant gap in our understanding of the coastal carbon cycle, resolve imbalances in marine budgets, and feed global models that overlook a key source. It will also reveal if blue carbon habitats act as buffers or drivers of ocean acidification.

If our ocean outwelling hypothesis proves correct, the sequestration capacity of blue carbon ecosystems (based on soil carbon only) has been greatly underestimated.

Hence, this project may create new, strong science-based arguments for preserving or rehabilitating threatened blue carbon habitats and maximize natural climate solutions.