Nature reveals a hidden connection between Sahara dust and the Amazon rainforest:
Significant amounts of plant nutrients have been found in atmospheric mineral dust blowing from a vast central African basin to the Amazon, where it could compensate for poor rainforest soils.
The basin, known as the Bodélé depression, is the site of a once-massive lake in Chad. Bodélé is thought to be the dustiest place on Earth.
Charlie Bristow, a sedimentologist at Birkbeck, University of London, and lead author of the study, says, “A hypothesis we are investigating at the moment is that because it’s coming from the lakebed, this iron is going to be more bioavailable than if it were coming from the deeply weathered surface of the Sahara.”
“The Amazon is essentially a leached or leaching system,” says Bristow. Nutrients in the soil are washed away by rains. “So although it is very productive, it is actually quite nutrient-poor.”
So nutrient input is vital to the rainforest.