We evaluated whether French forest soils are sources or sinks of carbon?
Soils were resampled after 15 years in the 102 French forest monitoring plots.
Forest soils across France have accumulated 0.35 MgC ha− 1 yr− 1 between 1993 and 2012.
Soil carbon sequestration declined with tree age and was affected by stand structure.
Forest management has the potential to influence this carbon sink.