In my project called AirMicrome, I work on the process of airborne microbial colonization of surface communities. Microbes aerosolized in the air by wind or stochastic events such as storm and volcanic eruption have a hard time in the clouds: they experience stresses like starvation, freeze-thaw cycles and UV radiation, and the survivors that finally deposit have to face already settled microbial communities. The questions I am trying to answer are: What microbes are deposited from the air and where do they come from? How did they survive the atmospheric transport and the surface communities?
Iceland is the perfect place to study the colonization because of all the recent lava floors that were sterile during their formation: my team and I sampled air and fresh lava rocks in Surtsey, Fimmvörðuháls, and even in Fagradasfjall. We assessed and compared the microbial communities in each sample using culture-dependent and culture-independent methods, genomic and metagenomic analyzes. We selected good airborne candidates and checked their survival rates against simulated atmospheric stress factors. In addition, we discovered a new bacterial species sampled from the air of Surtsey in 2019.
This study will be the first to address microbial distribution in the atmosphere over Iceland in general and over pioneer volcanic environments in particular. The results will be relevant for understanding the process of early land colonization and therefore could be useful in the exploration of new planets. Moreover, it is likely that airborne communities will produce bioactive molecules that help them survive in the atmosphere and that can be useful in biotechnology.
Viggó Þór Marteinsson