Rainforests are often considered the lungs of the Earth, but oceans produce most of the oxygen we consume and store carbon more effectively.
The Secret in the Seas
Carbon stored in the ocean is called 'blue carbon'. This article explains what blue carbon is and how to protect it.
The Process of Carbon Sequestration
Blue carbon is trapped by ocean and coastal ecosystems through photosynthesis, where plants absorb carbon dioxide and convert it into oxygen and energy. According to Chris Fulton, a Principal Research Scientist at the Australian Institute of Marine Science, blue carbon is sequestered in ocean systems when organic matter like leaf litter, algae, seagrass, and timber becomes buried through processes such as cyclones, storms, or floods.
Carbon Pools and Their Importance
Blue carbon pools, particularly coastal wetlands including mangrove forests, seagrass beds, and tidal or mud flats, store significant amounts of carbon. These ecosystems also provide habitats for diverse organisms and prevent coastal erosion. However, they are vulnerable to climate change.
Autochthonous vs. Allochthonous Carbon
A study by Fulton and colleagues found that most blue carbon stored in pools comes from external sources. Autochthonous carbon originates and is buried within the same ecosystem, while allochthonous carbon is transported from elsewhere. This distinction affects conservation priorities: protecting the entire seascape, not just individual ecosystems, is necessary.
Protecting the entire seascape, not just individual ecosystems, is necessary.
The Blue Carbon Seascapes Project
The Blue Carbon Seascapes project aims to identify external carbon sources in northern Western Australia and understand where they are stored. The project has found that macroalgae (seaweed) are significant allochthonous carbon producers and may be underappreciated as blue carbon contributors.
Key Takeaway
Blue carbon is a potential solution to climate change, but its effectiveness depends on understanding and protecting the sources and storage sites of allochthonous carbon, particularly macroalgae.