Increases in forest carbon stocks of up to 32% by 2100 across the subalpine forests of the Tibetan Plateau

Forest carbon stocks dynamics, influenced by forest migration, growth, and mortality under climate change, remain insufficiently understood, particularly regarding their extent, timing, and geographic distribution. We studied data from 1,248 forest plots on the Tibetan Plateau to understand how forest carbon dynamics respond to climate and forest age and to predict future changes under different climate scenarios. Our findings suggest that forest carbon stocks in the eastern mountains of the Tibetan Plateau could increase by up to 32 % by 2100, reaching saturation as growth fluxes declines over time. However, growth fluxes offset the increase in mortality fluxes, which mitigates carbon losses. We also predicted that the carbon stocks distribution center will shift northwestward by 0.23 km/year and upslope by 0.25 m/year. The distribution of growth and mortality fluxes varies geographically. Regions with higher forest growth fluxes, particularly along the southern and northern edges and in transition zones, will experience faster precipitation migration. In contrast, areas on the northwestern edge and at lower altitudes, where temperature migration is faster, face elevated forest mortality risks. These results highlight the need for ecological compensation to mitigate increased mortality-related carbon and ensure sustainable forest management.