Seagrass Drift Helps Biscayne Bay Mangroves Combat Rising Sea Levels

Dead seagrass blades and seaweed from offshore meadows are drifting into Biscayne Bay's mangroves, piling up to become part of the forest floor ground. Researchers from FIU and the National Park Service found that natural soil buildup is falling behind sea-level rise, but drifting seagrass helps by adding material and slowing decomposition.

While sea levels rise 8.5 millimeters annually, the mangrove soil beneath is only rising 2 to 4 millimeters each year. Chemical analysis reveals that between 36% and 53% of surface carbon originates from the seagrass wrack, demonstrating its vital role in supporting the coastal ecosystem's defense against rising waters.

Editor's note: Faithfully reflects the study’s findings on sea‑level rise, mangrove soil elevation, and the 36‑53% carbon contribution from seagrass.