Restore America’s Estuaries has submitted “Greenhouse Gas Accounting Methods for Tidal Wetland and Seagrass Restoration” to the Verified Carbon Standard to begin the approval process. This ground-breaking methodology opens the door for all tidal wetland and seagrass restoration projects that meet the eligibility conditions to calculate net greenhouse gas benefits and receive carbon credits.

“This global methodology sets the stage to connect coastal restoration and carbon finance. We expect it will stimulate coastal wetlands carbon projects around the world, from mangroves and seagrass of the Coral Triangle to rebuilding tidal marshes here in the U.S.,” said Jeff Benoit, President of Restore America’s Estuaries.

Coastal blue carbon refers to the role of coastal wetlands (tidal marshes, seagrass meadows and mangroves) in contributing to the global carbon cycle. Coastal wetlands sequester carbon dioxide from the atmosphere and store it in the form of biomass and soil carbon. Though only representing 2% of the world’s surface area they sequester 50% of the carbon that is transferred to marine soils and sediments.

Coastal wetlands are under threat and represent one of the highest rates of loss for any ecosystem globally. At current rates, within 100 years most of the world’s coastal wetlands will be lost. In the United States losses are increasing as well.

Restoration of coastal ecosystems brings benefits that support the livelihood of local communities, improve fisheries, reduce risk of flooding, provide future climate change adaptation benefits, and reverse ongoing greenhouse gas emissions from converted wetlands.

Methodology development was lead by Restore America’s Estuaries with financial support from the National Estuarine Research Reserve System Science Collaborative, The National Oceanic and Atmospheric Administration’s Office of Habitat Conservation, The Ocean Foundation, The Curtis and Edith Munson Foundation, and KBR.

Methodology developers are Dr. Igino Emmer, Silvestrum; Dr. Brian Needelman, University of Maryland; Steve Emmett-Mattox, Restore America’s Estuaries; Dr. Steve Crooks, Environmental Science Associates; Dr. Pat Megonigal, Smithsonian Environmental Research Center; Doug Myers, Chesapeake Bay Foundation; Matthew Oreska, University of Virginia; and Dr. Karen McGlathery, University of Virginia.

The methodology outlines procedures to estimate net greenhouse gas emission reductions and removals resulting from restoration of tidal wetlands and seagrass beds along the entire salinity range, via enhancing, creating and/or managing hydrological conditions, sediment supply, salinity characteristics, water quality and/or native plant communities with the intent of protecting and restoring various environmental benefits including emission reductions and the net sequestration of greenhouse gases.

According to Steve Crooks, one of the authors, “we have worked hard to make this methodology applicable to the restoration community. It incorporates best practices and principles in restoration and carbon management, while leaving the flexibility necessary to enable projects to emerge in diverse coastal settings.”

The geographic scope of the methodology is global and includes all tidal wetland systems, including mangroves, tidal marshes and seagrass meadows.

“The VCS methodology is a major step for coastal habitat conservation because it applies to a broad array of ecosystem types – marshes, mangroves and seagrasses – and management activities,” said Dr. Pat Megonigal, a methodology author.

Eligible restoration activities include:

  • Removing tidal barriers
  • Improving water quality, particularly to increase seagrass extent
  • Management of organic soils such as subsidence reversal
  • Rewetting of drained wetlands
  • Lowering of water levels on impounded wetlands
  • Wetland creation through beneficial use of dredged material
  • Restoring salinity conditions
  • Revegetation
  • Combinations of the above

Restoring these blue carbon ecosystems provides the following potential GHG emission reductions or removals:

- Increasing biomass
- Increasing soil organic carbon
- Reducing methane and/or nitrous oxide emissions
- Reducing carbon dioxide emissions

For more information, contact Steve Emmett-Mattox, Sr. Director.