Carbon sink

Ecology

Marsh

Biology

Wetland

Ecosystem engineer

Vegetation (pathology)

Salt marsh

Seagrass

Blue carbon

Environmental science

Medicine

Peat

Carbon dioxide

Ecosystem services

Carbon sequestration

Ecosystem

Pathology

Science

Biogeomorphic wetlands cover 1% of Earth’s surface but store 20% of ecosystem organic carbon. This disproportional share is fueled by high carbon sequestration rates and effective storage in peatlands, mangroves, salt marshes, and seagrass meadows, which greatly exceed those of oceanic and forest ecosystems. Here, we review how feedbacks between geomorphology and landscape-building vegetation underlie these qualities and how feedback disruption can switch wetlands from carbon sinks into sources. Currently, human activities are driving rapid declines in the area of major carbon-storing wetlands (1% annually). Our findings highlight the urgency to stop through conservation ongoing losses and to reestablish landscape-forming feedbacks through restoration innovations that recover the role of biogeomorphic wetlands as the world’s biotic carbon hotspots.

Recovering wetland biogeomorphic feedbacks to restore the world’s biotic carbon hotspots