China's large-scale tree-planting efforts are delivering a new scientific insight: young planted forests may build leaf canopy faster than naturally regenerating ones. A study published in Geophysical Research Letters examined forest change across China from 2000 to 2022 and found that planted forests expanded their leaf area more quickly, especially in mixed and evergreen stands.
Researchers led by landscape ecologist Yuhang Luo of Peking University used satellite data to track the leaf area index, or LAI, a measure that helps estimate how much canopy covers the ground. At first glance, planted forests appeared to outperform natural forests by a wide margin. But after matching forests with similar ages, climates, vegetation types, and environmental conditions, the difference narrowed significantly.
Even after that adjustment, planted forests still showed a modest advantage, with leaf area rising 4.6% faster than comparable natural forests. Scientists say this is partly linked to the trees selected for planting, which are often fast-growing species, as well as management practices that reduce competition and improve growing conditions.
The study also points to rising atmospheric carbon dioxide as a major driver behind the canopy expansion in both forest types. Higher CO₂ can stimulate photosynthesis and leaf production when water, light, and nutrients are available. This response was stronger in planted forests, particularly in the 30- to 40-year age range, when many of China's plantations are still relatively young.
But the findings also highlight an important balance. Natural forests may grow more slowly at first, yet they tend to become more structurally complex and resilient over time. They support richer biodiversity and store carbon across trunks, roots, soil, and dead wood, not just in their canopies. In that sense, plantations and natural forests serve different roles in restoration and climate strategy.
The broader message is clear: fast-growing plantations can help accelerate early forest recovery, while mature natural forests remain essential for long-term ecological stability. Together, they point toward a future where restoration is measured not only by tree numbers, but by the quality and resilience of living landscapes.
