Sahara is the largest warm desert in the world. It occupies almost all of northern Africa, namely 8.5 million km², and its area is constantly growing. But this desert area, which conveys an image of desolation and dryness, helps fertilize one of the most lush areas in the worldExactly Amazon forest.
ActuallyThe sands of the Sahara manage to move across the Atlantic Ocean, over more than 6000 km, to reach the Amazon, the planet’s green lung located in South America. In fact, this fascinating phenomenon has been the subject of research by NASA, which has revealed the conclusions of its study to the general public.
Data revealed by NASA thus shows the close relationship between the desert and the forest despite the geographical distance. They were collected between 2007 and 2013, although the connection phenomenon had already been identified by scientists for several years.
Phosphorus from the sands of the Sahara feeds the vegetation of the Amazon
That is the opinion of scientific experts 182,000 tons of dust cross the Atlantic to reach America from the Sahara. Of this, a total of 27.7 million tons of sand enter the Amazon Basin each year, providing a valuable supply of phosphorus (an essential nutrient for plants), according to researchers from the University of Maryland (USA).
Thus, 22,000 tons of phosphorus are added to the Amazon vegetation. According to the study, this amount is sufficient satisfy the nutritional needs that the Amazon rainforest is losing when the region is hit by heavy rainfall and floods. Drainage water promotes the loss of phosphorus from the soil. However, this natural fertilizer is essential for the growth of plants.
“The entire Amazon ecosystem depends on Sahara sand to rebuild lost nutrients”said study coordinator Hongbin Yu.
The analysis confirms what many, even without a scientific basis, have known for a long time:
“This is a small world and we are all connected.”
Sand, rich in nutrients, comes mainly from a region known as Bodélé depression. it is a topographical depression located in the southern center of the Sahara, in northern Chad. The Depression hosted a lake during the wettest period the Sahara experienced during the Holocene.
But most of the dust remains suspended in the air while 43 million tons reach the Caribbean Sea. This large study was made possible thanks to data collection performed by the Calipso satellite. NASA published its research in the specialized journal Geophysical research letters.
The two ecosystems are connected despite the Atlantic separating them
Thanks to a NASA animation, we see that scientists were aware of the existence of this phenomenon. But it shows the data collected the direct connection between the two ecosystems.
The transoceanic phenomenon analyzed is not a simple anecdote. In fact, a large part of The richness of the plants in the tropical forest of South America depends on the fertilizers contained in the dust of the Sahara.
One of the most interesting data in the study specifies that after a rainy period in the Sahara region, the amount of dust moving by the wind is smaller. Therefore, one can imagine that if the Sahara were a more humid zone, the transport of phosphorus would be more limited and the Amazon basin would not have the necessary fertilizer to maintain its current balance.
This is a great demonstration of the butterfly effect, which testifies to the connection between ecosystems a priori as far apart as they are different.
“This is a small world and we are all connected […] It is an essential component of the earth system. The dust will affect the climate and at the same time climate change will affect the dust ”,
A particularly significant Sahara sand cloud in 2020
Last year cloud of sand from the Sahara was more important than ever in the Caribbean and in the northern part of the South American continent between June and September.
In fact, scientists noted that this impressive cloud of dust, called “Godzilla”, had affected air quality:
“It’s the first time we’ve seen from space that the event has reached this magnitude. It’s a mega cloud. We had not seen anything like it in 50 years.”explained Sidney Novoa, director of conservation technology at the organization Amazon Conservation (ACCA).
Minerals carried by dust from the Sahara provide essential nutrients to soils that are weakened by, for example, excessive agricultural practices, and also nourish the oceans.