Home / Science / Saharan Dust Bathes Amazon in Exotic Bacteria
Saharan Dust Bathes Amazon in Exotic Bacteria
10 Nov
Summary
- Saharan dust transported a distinct bacterial community across the Atlantic.
- Airborne endotoxin levels tripled during the dust event in the Amazon.
- Fungal communities in the Amazon remained largely unaffected by the dust.
In February 2020, a significant event occurred over the Amazon rainforest when Saharan dust, having traveled across the Atlantic for ten days, deposited a unique bacterial community. Researchers at the Amazon Tall Tower Observatory collected aerosol samples, revealing that mean aerosol mass concentrations increased nearly eightfold during this five-day intrusion.
The bacterial populations within the Amazon's air shifted significantly, showing a strong resemblance to organisms found in dryland soils and marine environments. Notably, airborne endotoxin concentrations, which can trigger inflammation, roughly tripled during the dust event. These endotoxins originated from dead microbial material from African drylands and marine debris.
In contrast to the bacteria, the fungal community within the rainforest air showed little change. Wood-decomposing fungi remained dominant, likely due to abundant local spores masking any arriving fungal material. The study, published in Communications Earth & Environment, continues to investigate the viability of these transported microbes and their potential impact on human health.
