Unleashing the land sector's potential for climate mitigation requires purposedriven changes in land management. However, contributions of past management changes to the current global and regional carbon cycles remain unclear. Here, we use vegetation modelling to reveal how a portfolio of ecological restoration policies has impacted China's terrestrial carbon balance through developing counterfactual 'no-policy' scenarios. Pursuing conventional policies and assuming no changes in climate or atmospheric carbon dioxide (CO 2 ) since 1980 would have led China's land sector to be a carbon source of 0.11 Pg C yr -1 for 2001-2020, in stark contrast to a sink of 175.9 Tg C yr -1 in reality. About 72.7% of this difference can be attributed to land management changes, including afforestation and reforestation (49.0%), reduced wood extraction (21.8%), fire prevention and suppression (1.6%) and grassland grazing exclusion (0.3%). The remaining 27.3% come from changes in atmospheric CO 2 (42.2%) and climate (-14.9%). Our results underscore the potential of active land management in achieving 'carbon-neutrality' in China.

The dynamics of the terrestrial ecosystem carbon balance are driven collectively by environmental changes and direct land management 1-4 . Future environmental changes such as climate change and atmospheric CO 2 increase (or decrease) hinge on the climate policies of all nations. Hence, the resulting land carbon responses are beyond the control of any specific nation. In contrast, options for active changes in land management to increase carbon stock or avoid emissions lie within the reach of each individual nation. Indeed, of the declared or submitted nationally determined contributions (NDCs) to implement the Paris Agreement, 10%-30% of the planned reductions in global emissions will be provided by active changes in land management 5,6 .