Wetland fragmentation associated with large populations across Africa

Abstract

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 yr−¹, nearly ten times the carbon sequestration of pristine wetlands (27 MtC yr−¹). These findings provide a crucial foundation for sustainable wetland management and policy development.