Understanding how much carbon enters the atmosphere when a wetland is drained for agriculture or other purposes requires a more detailed understanding of the soil make-up.
All of this information must be plugged into models to project how wetlands will evolve in the coming decades — and whether they will be able to keep pace with rapidly rising seas, says John Rybczyk, a wetlands ecologist at Western Washington University in Bellingham. His analysis of a 61-hectare marsh restoration project that was completed in Washington’s Puget Sound in 2012 found that the site would sequester an additional 5,660–13,200 tonnes of CO2 over the next 75–100 years.
That’s enough to fetch around $200,000 on voluntary carbon markets that allow companies to offset their emissions by funding conservation projects. “You aren’t going to change the carbon balance of the globe doing that, but you can use it as another tool to fund some of the restoration projects,” Rybczyk says.