Climate security

Threatened blue carbon ecosystems store carbon 40 times faster than forests

Blue carbon coastal ecosystems — such as mangroves, seagrass meadows and tidal wetlands — are named for their place at the boundary between land and sea, and their unmatched ability to suck CO2 out of the atmosphere and store it in the ground below.

This process is called carbon sequestration.

• Coastal plants capture CO2 through photosynthesis and land-based carbon sources
• Carbon can be stored in the soil of blue carbon habitats for thousands of years
• When these habitats are damaged or destroyed the carbon can be released as CO2 back into the atmosphere

It was intense carbon sequestration by ancient forests and algae millions of years ago that helped create the very deposits of coal and oil we tap into for fossil fuels today.

Nearby on the ecology colour palette are the better-known green carbon systems of trees and forests. While important, they aren't nearly as efficient at storing carbon as their blue counterparts.

"We know that forests are pretty good at [carbon sequestration], but their carbon stores are bound to the lifetime of the trees, for only 100 or so years, and then it is released back into the atmosphere," Dr Macreadie said.

As well as being a temporary carbon store, trees can only soak up so much carbon before they become "saturated".