Getting to the root of marsh loss

ionah on June 26, 2025

Triptych diagram showing how marsh loss is driven by sea level rise
Conceptual diagram highlighting how a healthy salt marsh (left) converts to a vulnerable marsh via loss of belowground material (center) before loss of vegetated marsh (right) as a result of increased inundation intensity, which is driven by sea level rise. Source: Runion et al. 2025.

GCE-affiliated researchers have published a new paper in the Proceedings of the National Academy of Sciences on the patterns and trends of belowground biomass in salt marshes. The team, led by Kyle Runion (UT Austin, now a Research Scientist at UGA) and Jessica O’Connell (Colorado State), used the Belowground Ecosystem Resiliency Model (BERM) to estimate both above- and belowground biomass of Spartina marshes along the entire Georgia coast (691 km2) over a ten-year period (2014-2023). Most of the field data used to calibrate the model came from samples collected on Sapelo Island. The researchers found that a decline in belowground material often preceded above-ground loss, making it an important indicator of marsh vulnerability. You can read more about it here, and access the paper itself here.