When you think about glaciers in the Antarctic, you probably picture a lot of ice, snow, and water. The frozen areas of our world don’t usually sustain many life forms. But look more closely, and you’ll find something bigger than what you’d expect.
Scattering the glaciers are cryoconite holes, which could have a great impact on scientific ideas, and could be contributing to global warming and rising sea levels. Not only this but studying these holes could lead to more advanced information on our own systems.
“The idea is that (cryoconite) holes may tell us something about what goes on in our own microbiomes,” said Pacifica Sommers, a postdoctoral researcher at the University of Colorado. “We’re looking at this to understand why these communities are the way they are.”
According to Sommers, these holes are formed when sediments from around the environment land on the glaciers.
The holes then refreeze an ice lid on top, a trait usually found only in the holes in Antarctica. This creates a mini test tube of microorganisms, sealing the tiny ecosystem from the surrounding environment.
“They look like clear ice with some sediments on the bottom,” said Sommers.
The cryoconite holes act as what Sommers called a ‘real-world test tube’ in learning about microbial communities. The holes contain an ecosystem that includes a number of different and small lifeforms, such as tardigrades, algae, rotifers, and even insects. Tardigrades and rotifers are microscopic animals that live in these environments.
These species exist together as hot spots of ecosystem diversity. But why is it important to study?
The team is studying microbial community assembly, specifically why biological communities are the way they are.
The team from CU is studying microbial community assembly, specifically why biological communities are what they are. The study could also be an insight into ecosystem formation. Many details of how biological communities form are still unknown, and studying these simple systems could bring about answers on how larger ecosystems have formed over the years.
“A lot of systems are just very complicated, and here you have very simple food webs, very simple,” said Dorota Porazinska, a CU Boulder research associate on the project.
Porazinska said that starting with simple systems is a quicker way to observe characteristics, as it would take years to study larger systems such as forests and grasslands. Looking at the ecosystems found in cryoconite holes gives researchers the potential to link how these systems to larger, more complex systems.
The study has two goals: to sample naturally occurring holes and to create their own holes in the glaciers. The team visited three glaciers in the Taylor Valley of Antarctica: the Commonwealth Glacier, Canada Glacier, and the Taylor Glacier.
“We take a helicopter up onto the glacier, and then we use this core to drill down into the cryoconite holes, pull up a big chunk of frozen ice, with some sediments in it,” said Sommers.
They then fly the samples back to the labs, where they can extract DNA, carbon, nitrogen, and other components to study the environmental characteristics of the cryoconite. The team also collected ice samples from the glacier to compare to the extractions from the holes in order to see how they differ.
The data acquired by the team has not yet been released, but work is still underway. The team is now embarking on their second trip to the Antarctic to continue studying these microbiomes. On this trip, they will create more cryoconite holes, inserting different combinations of microbes into the holes.
The experiment will then continue into the third year, where the team will once again visit the holes to see how their microbial communities have developed and how they are different from the naturally occurring cryoconite holes.
In the end, the team hopes to have a better understanding of how microbial communities work and be able to link that information to larger, more complex communities.
