Ecosystem services (ES) are now taken into account in management schemes and impact studies. Given current climate change, global climate regulation by ecosystem carbon storage is an ES of great concern. This is especially the case for wetland protection and restoration, which as fragile ecosystems are already managed for conservation. We used a state-and-transition model for 24 wetland plots to determine whether such management actions can change their carbon stock. Aboveground biomass of forested wetlands stored twice as much carbon as herbaceous undrained wetlands. Soil organic carbon stock was unchanged across the three studied main states, and was thus independent of their vegetation. This study highlights the importance of the wetland soil carbon pool for global climate regulation, as it represented > 50 % of the total carbon stock for the three studied states, but also the difficulties to manage this complex pool. Also, it points out the advantage of state-and-transition models to follow and/or project management effects on ES. This approach could be used in the context of the mitigation hierarchy for No Net Loss of biodiversity and ecosystem services