Integrating remote sensing-based maps of biomass and disturbances for future forest carbon sequestration scenarios in France

Forests play a central role in climate change mitigation, yet large uncertainties persist in quantifying their future carbon sequestration potential, particularly under increasing disturbance pressure. Here we develop a spatially explicit, species-resolved assessment of present and future forest carbon dynamics in France by integrating high-resolution Earth observation products with national forest inventory data. Using 10–30 m maps of above-ground biomass, tree species composition, and disturbance history derived from satellite observations, we reconstruct species- and region-specific forest growth curves through a space-for-time approach, independently constrained using field measurements from the French National Forest Inventory. These growth curves are assimilated into a data-driven bookkeeping model that tracks annual biomass gains and losses from growth, harvest, and natural disturbances across metropolitan France from 2020 to 2050.

Our results indicate that, in the absence of disturbances, French forests could increase above-ground carbon stocks by up to 32% by 2050, driven primarily by the growth of young conifer stands. However, when realistic disturbance and harvest regimes extrapolated from recent trends are accounted for, net carbon accumulation is reduced to 23%, highlighting the strong moderating influence of unplanned disturbances and management. Carbon sequestration potential and resilience vary markedly across species and regions: mixed and deciduous stands generally exhibit greater robustness, whereas intensively managed conifers—particularly fir–spruce, Douglas fir, and maritime pine—are disproportionately vulnerable to combined disturbance and harvest pressures.

By explicitly representing forest demography, species composition, and disturbance regimes at high spatial resolution, our framework delivers a realistic projection of the French forest carbon sink to mid-century. These results provide actionable insights for forest-based mitigation strategies, revealing where carbon storage can be enhanced, where resilience is limited, and how current management trajectories may constrain future climate benefits.