China’s planted forests are growing their canopies faster than the natural forests beside them, expanding their leaf cover 65.8 per cent more quickly across the country. That is the headline finding of new research that could reshape how governments count carbon in the world’s plantation estates.
Published in Geophysical Research Letters, the study saw scientists from Peking University and Beijing Forestry University analyse four decades of satellite data across China’s Three-North Shelterbelt Program. The afforestation drive is better known worldwide as the “Great Green Wall.”
Since 1978, China has planted an estimated 66 billion trees along its northern flank to hold back the Gobi and Taklamakan deserts. The living barrier now rivals the Great Wall itself in scale.
Once the authors stripped out the effect of younger trees and kinder growing conditions, the gap narrowed sharply to 4.6 per cent. Planted stands average 34 years against 57 for natural forests, and even that slim edge fades as the trees mature, all but closing after roughly 40 years.
The remaining advantage comes down to how vigorously young, planted stands respond to rising carbon dioxide, particularly mixed and evergreen species. Using leaf area index data, propensity score matching and machine learning, the team separated the effects of age, CO2 and climate to compare like with like.
Carbon markets increasingly rely on fast-growing plantations to generate credits. Yet most climate models treat forests as broadly interchangeable, Luo said, even though young plantations bank carbon quickly and then surrender that edge as they age.
Carbon credits are issued on the assumption of steady, lasting storage. “For long-term carbon storage and resilience, natural forests remain irreplaceable,” Luo said.
Not everyone is convinced the satellites tell the whole story. Canopy greenness captures only a sliver of a forest’s carbon, said David Orwig, a forest ecologist who was not involved in the work.
“The canopy is just the top of the tree,” Orwig said, pointing to the carbon locked in wood, bark, roots and soil that a satellite cannot see.
The findings come as China pivots from the world’s largest timber importer towards “wood-product self-sufficiency.” It is building out the vast eucalypt estates that trace back to an Australian breeding programme at Dongmen.
Those estates carry the trade-offs Australian foresters know well. Monoculture plantations prized for rapid establishment hold thinner biodiversity than the native forests they often replace, and their denser canopies draw more moisture from the soil, a live issue for plantation siting in a drying climate.
Growth, the authors stress, is not the same as storage. A young plantation can green quickly and still hold far less carbon than an old natural forest bank in its trunks, roots and soil over centuries.
Better forestry, Luo argued, now turns on more than the number of trees in the ground. It depends on when they are planted, which species are chosen, and how the stands are managed across a full rotation.
China has pledged to raise forest cover to more than 24 per cent of its landmass by 2025 and to conserve 70 billion trees by 2030. Those targets now rest on the carbon-accounting models this study says are getting the maths wrong.
For more information: Luo, Y., et al. (2026). Enhanced CO2 Response and Aging-Related Dynamics Drive a Greater Leaf Area Index Increase in China’s Planted Forests in Comparison to Natural Forests. Geophysical Research Letters, 53, e2025GL121544. https://doi.org/10.1029/2025GL121544
