Although its cradle is the sparsely wooded savannah, humankind has long looked to forests for food, fuel, timber and sublime inspiration. Still a livelihood for 1.5bn people, forests maintain local and regional ecosystems and, for the other 6.2bn, provide a—fragile and creaking—buffer against climate change.
Now droughts, wildfires and other human-induced changes are compounding the damage from chainsaws. In the tropics, which contain half of the world’s forest biomass, tree-cover loss has accelerated by two-thirds since 2015; if it were a country, the shrinkage would make the tropical rainforest the world’s third-biggest carbon-dioxide emitter, after China and America.
Nowhere are the stakes higher than in the Amazon basin—and not just because it contains 40% of Earth’s rainforests and harbours 10-15% of the world’s terrestrial species. South America’s natural wonder may be perilously close to the tipping-point beyond which its gradual transformation into something closer to steppe cannot be stopped or reversed, even if people lay down their axes.
