Tropical forests are losing their ability to absorb carbon

The carbon sequestration capacity of pristine tropical forests around the world has dropped by about a third from the 1990s, the new study says.

The conclusion came after three decades of tracking more than 300,000 woody trees inside unaffected tropical rainforests in the Amazon and Africa. The research, conducted by scientists from Europe and Africa, was published in the journal Nature last week.

Amazon forest at dawn.(Photo: Peter Vander Sleen).

The team, led by the University of Leeds in the UK, said they used aluminum nails to mark each tree and returned to the test after a few years to measure their diameter and height. This allows them to calculate the amount of carbon stored inside living or dead trees. The recorded data shows that tropical forests now absorb less than one-third of the carbon that was measured in the 1990s.

Research has provided evidence that tropical forests in Africa have shown signs of carbon sequestration decline since 2010, later than in the Amazon region. This is because the Amazon rainforest is more severely affected by global warming, with temperatures rising faster and droughts occurring more frequently.

The team predicts that in the next 10 years, African forests will absorb 14% less carbon dioxide . By the 2060s, typical tropical forests around the world could even become the source of carbon emissions due to forest fires, deforestation and excess greenhouse gases released into the atmosphere. "Instead of diminishing, rainforests can exacerbate climate change," said ecologist Simon Lewis at the University of Leeds.

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