Ancient African lake fertilises the Amazon

WINDBLOWN dust from a dried-out African lake that was once the size of California is nourishing rainforests in the Amazon and algae in the Atlantic.

Previous modelling studies estimated that the Bodélé depression in Chad, which formed when the largest lake in Africa dried out about 1000 years ago, is responsible for about 56 per cent of the dust from Africa reaching the Amazon, amounting to millions of tonnes per year.

Now, researchers have estimated how much fertiliser, in the form of iron and phosphorus, is in the dust. Although the…