Litterbag decomposition after runnel restoration in southern Massachusetts salt marshes from 2020-2022.

Natural disturbances, sea level rise, and historic human impacts to salt marshes have increased impounded water on marsh surfaces, resulting in vegetation loss and the associated loss of important ecosystem services such as carbon storage. Runnels are a climate adaptation technique designed to restore salt marsh habitat by reestablishing a tidal connection between impounded water and a nearby drainage feature. While runnels can drain impounded water and promote revegetation, the unintended effects of altering redox conditions remain unknown. Panne formation and runnel restoration could alter organic matter decomposition of litter. Therefore, we measured litterbag decomposition in two MA marshes for 3 years: 1 year prior to restoration, and two years post.