A dried lakebed in Africa's Chad sends 27.7 million tonnes of dust across 5,000 km of Atlantic Ocean each year, carrying phosphorus that helps sustain the Amazon rainforest

The Amazon rainforest has a surprising lifeline. Each year, about 27.7 million tonnes of Sahara dust travel nearly 5,000 kilometres from Chad’s Bodélé Depression across the Atlantic Ocean. The dust carries around 22,000 tonnes of phosphorus, a vital plant nutrient. Amazon soil loses phosphorus through heavy rainfall and flooding. African dust helps replace part of that loss. An ancient lakebed in Africa is quietly helping sustain the world’s largest rainforest.