Soil Nitrogen Doubles Tropical Forest Regrowth Speed

A simple nutrient hiding in the soil could help the planet fight climate change much faster than anyone expected.

Scientists at the University of Leeds just completed the largest tropical forest recovery study ever attempted. After tracking 76 forest plots across Central America for up to 20 years, they found that forests with adequate nitrogen in their soil bounce back at double the speed of those without it.

The research team tested different nutrient combinations on cleared forest land once used for logging and agriculture. Some plots got nitrogen fertilizer, others received phosphorus, some got both, and others were left untreated. Only nitrogen made forests regrow dramatically faster during the crucial first 10 years of recovery.

Lead researcher Wenguang Tang says the discovery opens new doors for capturing greenhouse gases through smarter reforestation. But the team isn't recommending we dump fertilizer everywhere. Widespread fertilizer use could release nitrous oxide, which ironically makes climate change worse.

Instead, scientists suggest two practical solutions that work with nature. Forest managers could plant more trees from the legume family, like beans, which naturally add nitrogen to soil as they grow. Another option is restoring forests in areas that already have enough nitrogen from air pollution effects.

The climate stakes are enormous. Tropical forests rank among Earth's most powerful carbon sinks, pulling carbon dioxide from the air and locking it away in trees. The researchers estimate that nitrogen shortages in young tropical forests worldwide may be preventing the capture of 0.69 billion tonnes of carbon dioxide every year. That equals two full years of all greenhouse gas emissions from the entire United Kingdom.

The Ripple Effect

The timing couldn't be better. This research arrives just weeks after COP 30 in Brazil, where world leaders announced the Tropical Forest Forever Facility to protect and restore tropical forests. The findings give policymakers concrete science to guide where and how they invest restoration funds for maximum carbon capture.

Dr. Sarah Batterman, who led the research team, stresses that protecting existing mature forests should always come first. But understanding how nutrients affect regrowth helps decision makers choose the smartest restoration strategies.

The study included experts from Yale, Princeton, Cornell, and the Smithsonian Tropical Research Institute. Their findings were published in Nature Communications on January 13.

Smart reforestation guided by soil science could help forests fight climate change twice as fast.