Floodplain habitats of the Xilin River in Inner Mongolia, China, were overgrazed by sheep and cattle until fencing of the floodplains was implemented in 2000. Carbon cycling of three plant communities of differing floodplain elevation after fencing showed that biomass in low-elevation wetlands increased fastest until reaching its maximum at 20 years in the future, while a slower increase in biomass existed in high-elevation and 'hummock' wetlands. Modelling and field experiments revealed differences between the three plant communities that were primarily attributed to different elevation levels and inundation periods. This study also determined the carbon sequestration capacity of the three floodplain wetland types (0.18 kg C m À2 year À1 in low-elevation wetlands, 0.09 kg C m À2 year À1 in high-elevation wetlands, and 0.05 kg C m À2 year À1 in hummock wetlands).