R-22-23-Johnson Methane emissions and carbon sequestration in tidally restricted salt marshes

Beverly Johnson
Bates College

Claire Enterline
Maine Coastal Program, Department of Marine Resources


Salt water marshes are known carbon sinks, providing habitat for organisms that absorb carbon from the atmosphere. However, when road crossings or other structures reduce the amount of tidal water flowing into and out of a salt marsh, the habitat may become hostile for those organisms and allow for methane-producing bacteria to flourish. This study aims to measure carbon gas emissions (methane) and carbon absorption in marshes along the Maine coast at sites where tidal flow has been restricted. These data will give researchers and resources managers a better understanding of how marsh restoration efforts could help Maine reduce carbon emissions and achieve goals laid out in Maine Won’t Wait: A Four-year Plan For Climate Action. 

Two-year project, 2022-2024
Sea Grant funds: $140,215