Wetland fragmentation associated with large populations across Africa.

Wetlands provide essential ecosystem services in Africa, yet their extent and fragmentation remain poorly understood. Here we classify African wetlands at 10 m resolution, using seasonal composite imagery and a random forest algorithm. We estimate a total wetland area of 947,750 km² (10% of global wetlands), comprising 46% marshes, 25% swamps, 22% peatlands, 5% seasonal wetlands, and 2% mangroves. Wetland fragmentation is strongly associated with high population densities in countries such as Nigeria, Liberia, Guinea, Egypt, Algeria, and Kenya. African wetlands store an estimated 54 ± 11 Gt of carbon, surpassing Europe's 12-31 Gt. If drained, they could release 260 MtC yr¹, nearly ten times the carbon sequestration of pristine wetlands (27 MtC yr¹). These findings provide a crucial foundation for sustainable wetland management and policy development.