China’s ambitious reforestation lead has added 28 million hectares of new trees since the 1990s, but its ecological impact is more complex than previously thought. Research published in April 2026 in Communications Earth & Environment found that more than half of new plantations were established within one kilometer of existing natural forests, intensifying habitat fragmentation and raising concerns for wildlife. The distinction matters: an increase in forest area does not by itself show whether natural-forest quality or habitat connectivity has improved. Ecological function also needs to be assessed separately.
The study analyzed changes from 1990 to 2020. China’s total forested area grew, but the distinction between natural forests and planted monocultures proved critical. In 60% to 64% of the provinces and counties examined, fragmentation of natural forests increased even as plantation fragmentation decreased. By 2020, more than 1,000 counties had reached levels of fragmentation the authors considered severe, compared with 945 in 1990. A separate analysis of forest ecosystems found that their share of China’s land area rose from 24.70% in 2000 to 25.24% in 2023. That measure tracks area, but does not by itself capture habitat structure or biodiversity.
Monocultures and Hidden Risks
Researchers warn that simply counting trees does not amount to preserving natural forests. Plantations, often monocultures of fast-growing species, have created new edges, isolated wildlife populations and disrupted genetic exchange. Examples include eucalyptus and bamboo, as well as Japanese cedar. A 2026 review in Forests, which assessed 190 Chinese- and English-language publications, including 118 empirical studies, also identified persistent structural imbalances in planted forests. These include high proportions of pure stands and young or middle-aged trees.
Some government programs, including the Natural Forest Protection Programme, have helped slow fragmentation in targeted areas. The programme has been associated with logging bans or reductions across 68.2 million hectares, including 56.4 million hectares of natural forest, about 53% of China’s natural forests. Plantation area reached 69.3 million hectares by 2013, reflecting the broader shift in timber supply. These measures help explain why forest expansion and conservation outcomes need to be assessed using more than tree cover alone.
A 2016 study published in Nature Communications focused on the Grain for Green programme, which restored nearly 28 million hectares by 2013 at a cost of $46.9 billion. Reviewing 258 publications and field data from 202 sites, researchers found that 82% of plantations were monocultures, with native forest reported at only a handful of sites. Mixed-species plantations were rare and typically included just two to five species. The programme, also known as the Sloping Land Conversion Programme, began in 1999 and has delivered vegetation gains, though its effects vary with local conditions. Research on the Loess Plateau published by Feng and colleagues in Nature Climate Change in 2016 found that planting increased vegetation productivity and evapotranspiration while reducing the share of precipitation that became river runoff. In this water-limited region, the study concluded that productivity was already close to the limit imposed by available water. Species selection and planting density so matter to restoration planning.
Impact on Birds and Bees
Fieldwork in Sichuan province used birds and bees as indicators of environment health. The results were stark: monoculture plantations supported bird diversity similar to or lower than that of agricultural land, while mixed forests offered a modest improvement. Bee species richness dropped by up to 92% in plantations compared with cropland. Native forests consistently outperformed plantations, supporting far more bird and bee species. Researchers identified the lack of flowers and understory vegetation in monocultures as a likely cause of the decline in pollinators.
Other research shows why canopy cover alone is an incomplete measure of habitat. An analysis of 494 fecal samples from 44 bird species identified 2,282 bird-arthropod interactions across restored and basic forests in China. Simulated removal of abundant bird species particularly destabilized food-web networks in plantations. Removing large birds weakened networks in both plantation and basic-forest systems. The findings show that restored canopy does not automatically reproduce the ecological networks of natural forests.
Although mixed plantations improved bird diversity compared with monocultures, they still fell short of native forest levels. The findings echo concerns about other measures to protect native bees from invasive species, and point to the complexity of managing biodiversity in changing landscapes.
Mixed Results and Policy Implications
Not all recent studies paint a negative picture. Research published in November 2025 modeled habitat suitability for 402 non-migratory forest bird species and found that nearly three-quarters expanded their suitable habitat between 2000 and 2020. Average species richness increased, with both protection and reforestation programs contributing to those gains. But, the authors cautioned that a greater number of species does not necessarily mean ecological functions have been preserved. They called for further studies of other animal groups.
Experts agree that protecting natural forests requires native species and mixed forestry practices, with diverse canopies basic to that approach. Interviews with rural households showed that mixed forests provided economic returns similar to those of monocultures, suggesting biodiversity-friendly approaches need not come at a financial cost. The 2026 review in Forests likewise called for differentiated forest management and decisions based on multiple ecological criteria. It also noted a spatial mismatch between carbon-sink benefits and local costs, including water consumption.
Cases such as the reforestation of holm oaks in Valencia, later cleared for solar panels, underscore the importance of forest permanence and composition in measuring biodiversity and ability to recover. Tree cover alone is not enough. China’s experience shows that forest quality and connectivity matter as much as quantity.
