Volcanic Microbes: How They Thrive After Eruptions

Summary of Research on Microbial Colonization of Lava Flows in Iceland

This research, conducted by a team from the University of Arizona, investigated how microbial life colonizes newly formed lava flows, a process previously poorly understood. They studied the Fagradalsfjall volcano in Iceland, which erupted three times between 2021 and 2023, providing a natural laboratory for thier research.

Key Findings:

* Initial Colonization: The first microbes to colonize the sterile, nutrient-poor lava flows are hardy organisms capable of surviving extreme conditions (low water, low nutrients). These “badass” microbes arrive primarily via windblown soil and aerosols.
* Rainwater’s Role: After the first winter, rainwater becomes the dominant source of new microbes, significantly shaping the microbial community. This is likely due to microbes existing within the atmosphere and functioning as cloud condensation nuclei.
* Biodiversity Changes: Microbial biodiversity increases in the first year after an eruption, but then decreases significantly after the first winter, stabilizing over time as a specific subset of microbes adapted to the harsh conditions prevails.
* Extreme Environment: Lava flows represent one of the lowest biomass environments on Earth, comparable to Antarctica or the Atacama desert.

Methodology:

* Researchers collected samples of freshly solidified lava, rainwater, aerosols, and surrounding soil/rock.
* They extracted DNA from these samples and used statistical and machine learning techniques to identify the organisms present and their origins.

Significance:

This study provides valuable insights into the ecological dynamics of microbial colonization in extreme environments and highlights the surprising role of rainwater – and the microbes within it – in shaping these communities. It also suggests that microbes may play a larger role in weather and climate phenomena than previously thought.