Weatherwatch: Saharan dust drops microorganisms into European soil

Scientists are examining how ‘blood rain’ affects soil microbiome, with Portuguese vineyards a particular focus

Dust events, when thousands of tonnes of fine sand whipped up from the Sahara are dumped over Europe, are becoming more intense. These sometimes produce “blood rain” that leaves visible red streaks, and while generally harmless, the dust is not sterile but brings a freight of microorganisms.

One big concern is how imported microbes may affect the soil microbiome and impact agricultural fertility and crop yield. Southern Portugal lies along one of the main deposition routes for Saharan dust, and the effect on vineyards in particular is a growing concern. A team from the University of Lisbon carried out genomic mapping of microbes in dust samples from 2022’s Storm Celia.