As climate change intensifies, forests remain among the most critical carbon sinks in terrestrial ecosystems, playing a vital role in safeguarding ecological security. Protected areas cover approximately 20% of China's land territory and serve as key spatial units for maintaining forest structural integrity and enhancing ecosystem carbon sequestration. However, China's protected area system still faces challenges including spatial fragmentation, overlapping designations, and inconsistent management effectiveness.

As China accelerates the establishment of a new protected area system centered on national parks, a systematic assessment is urgently needed to clarify how different protection levels and management regimes influence forest carbon storage, both currently and under future climate change.

To address this issue, researchers from the Aerospace Information Research Institute of the Chinese Academy of Sciences, in collaboration with the International Research Center of Big Data for Sustainable Development Goals and Aarhus University in Denmark, conducted a study and recently published their findings in Nature Communications.

By integrating spaceborne Global Ecosystem Dynamics Investigation (GEDI) lidar observations with simulations from the dynamic vegetation model LPJ-GUESS, the team conducted the first nationwide assessment of how different categories of protected areas contribute to aboveground forest carbon density. The study further projected future carbon gain potential under various climate scenarios and protection intensities.

The results show that China's protected areas have generally enhanced forest carbon storage, despite substantial variations across protection levels and management types. National parks and well-managed naturally regenerating forests display the strongest carbon gains. Overall, higher protection levels correspond to greater carbon sequestration potential.

Under a high-emissions scenario (SSP5–8.5), implementing stricter protection measures could yield an additional approximately 600 teragrams (Tg) of forest carbon storage by 2100. This increase equals roughly 19% of China's fossil fuel and industrial carbon emissions in 2023 and is comparable to the carbon gains achieved through afforestation expansion over the past three decades (637.2 Tg C).

The researchers emphasized that fully unlocking the climate mitigation potential of protected areas requires optimizing both spatial planning and management strategies. Key priorities include expanding protection to regions with high carbon stocks and high biodiversity, prioritizing the inclusion of unprotected intact forests, and improving management effectiveness in underperforming reserves. Meanwhile, efforts to boost forest carbon storage should be balanced with maintaining ecosystem resilience. Restoring faunal communities, allowing natural disturbance processes, and fostering structurally diverse and functionally rich forests can deliver synergistic benefits for both biodiversity conservation and climate mitigation.