Stories
African Dust Fertilizes Amazon: 27.7 Million Tons Deliver Vital Phosphorus Annually
- •Winds transport millions of tons of dust from North Africa across the Atlantic to the Amazon Basin each year, delivering essential phosphorus.
- •A 2015 NASA CALIPSO satellite study estimated 27.7 million tons of African dust reach the Amazon annually, carrying approximately 22,000 tons of phosphorus.
- •The Bodélé Depression in Chad was initially considered the primary source, but later research identified El Djouf as a more effective dust source for trans-Atlantic transport.
- •African dust provides an important external source of phosphorus for the Amazon, complementing the rainforest's internal nutrient recycling.
- •The amount of dust and phosphorus delivered varies annually, influenced by factors like rainfall in the Sahel, highlighting a dynamic connection.
Key Questions Answered
A 2015 satellite study using data from NASA's CALIPSO satellite estimated that approximately 27.7 million tons of dust from Africa blow into the Amazon Basin annually, carrying vital phosphorus to the rainforest ecosystem. Later studies suggest varying amounts, with some research estimating around 8 to 10 million tons each year.
While the Bodélé Depression in Chad was traditionally considered the main source, a 2020 study revealed that dust from the El Djouf desert has more favorable trajectories to travel across the ocean to the Amazon. Most dust from the Bodélé Depression tends to be deposited much closer to its origin.
The dust carries phosphorus, an important mineral for plants that is present in small amounts in most soil in the Amazon region. Imported dust is estimated to bring approximately 22,000 tons of phosphorus annually into the Amazon Basin.
