Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Glacier bacteria’s contribution to carbon cycling

06.04.2017

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a finding that has global implications as the bulk of Earth’s glaciers shrink in response to a warming climate.


Cotton Glacier stream in Antarctica

C. Foreman

The study was conducted by Heidi Smith and Christine Foreman of the Center for Biofilm Engineering in Montana State University’s College of Engineering, USA, Marcel Kuypers and Sten Littmann of the Max Planck Institute for Marine Microbiology in Bremen, Germany, and researchers at the University of Colorado at Boulder, the U.S. Geological Survey, Stockholm University in Sweden.

The paper challenges the prevailing theory that microorganisms found in glacial meltwater primarily consume ancient organic carbon that was once deposited on glacial surfaces and incorporated into ice as glaciers formed.

“We felt that there was another side to the story,” said Smith. “What we showed for the first time is that a large proportion of the organic carbon is instead coming from photosynthetic bacteria” that are also found in the ice and that become active as the ice melts, Smith said. Like plants, those bacteria absorb carbon dioxide and in turn provide a source of organic matter.

The research team made the discovery after sampling meltwater from a large stream flowing over the surface of a glacier in the McMurdo Dry Valleys region of Antarctica in 2012. Afterward, Smith spent two months at the Max Planck Institute for Marine Microbiology in Bremen, where she worked with colleagues to track how different carbon isotopes moved through the meltwater’s ecosystem, allowing the team to determine the carbon’s origin and activity.

The researchers ultimately found that the glacial microbes utilized the carbon produced by the photosynthetic bacteria at a greater rate than the older, more complex carbon molecules deposited in the ice, because the bacterial carbon is more “labile,” or easily broken down. The labile carbon “is kind of like a Snickers bar,” meaning that it’s a quick, energizing food source that’s most available to the microbes, Smith said.

Moreover, the researchers found that the photosynthetic bacteria produced roughly four times more carbon than was taken up by the microbes, resulting in an excess of organic carbon being flushed downstream. “The ecological impact of this biologically produced organic carbon on downstream ecosystems will be amplified due to its highly labile nature,” Foreman said.

Although individual glacial streams export relatively small amounts of organic carbon, the large mass of glaciers, which cover more than 10 percent of the Earth’s surface, means that total glacial runoff is an important source of the material. Marine organic carbon underpins wide-ranging ecological processes such as the production of phytoplankton, the foundation of the oceans’ foodweb.

As glaciers increasingly melt and release the organically produced, labile carbon, “we think that marine microbial communities will be most impacted,” Smith said. “We hope this generates more discussion.”

In a “News and Views” commentary accompanying the article in Nature Geoscience, Elizabeth Kujawinski, a tenured scientist at Woods Hole Oceanographic Institution, called the team’s work “an elegant combination” of research methods.

Taken together with another study published in the same issue of Nature Geoscience, about microbial carbon cycling in Greenland, Smith’s paper “deflates the notion that glacier surfaces are poor hosts for microbial metabolism,” according to Kujawinski. The two studies “have established that microbial carbon cycling on glacier surfaces cannot be ignored,” she added.

Based on Montana State University’s press release:
http://www.montana.edu/news/16819/msu-scientists-publish-study-on-glacial-carbon...

Original publication
H. J. Smith, R. A. Foster, D. M. McKnight , J. T. Lisle , S. Littmann , M. M. M. Kuypers und C. M. Foreman: Microbial formation of labile organic carbon in Antarctic glacial environments. Nature Geoscience. 

http://dx.doi.org/10.1038/ngeo2925

Begleitender News & Views
E. Kujawinski: The power of glacial microbes. Nature Geoscience.
http://dx.doi.org/10.1038/ngeo2933


Participating institutes
Montana State University, Bozeman, Montana 59717, USA
Stockholm University, Stockholm 10691, Sweden
Max Planck Institute for Marine Microbiology, Bremen 28359, Germany
University of Colorado, Boulder, Colorado 80309, USA
US Geological Survey, St Petersburg, Florida 33701, USA

Please direct your queries to

Dr. Fanni Aspetsberger
Dr. Manfred Schlösser
Phone: +49 421 2028 947 or 704
E-Mail: presse@mpi-bremen.de

Weitere Informationen:

http://www.mpi-bremen.de/en/Hotspots-for-biological-activity-and-carbon-cycling-... (related press release: Hotspots for biological activity and carbon cycling on glaciers)

Dr. Fanni Aspetsberger | Max-Planck-Institut für marine Mikrobiologie

More articles from Earth Sciences:

nachricht Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland
15.11.2018 | Faculty of Science - University of Copenhagen

nachricht The unintended consequences of dams and reservoirs
14.11.2018 | Uppsala University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

NASA keeps watch over space explosions

16.11.2018 | Physics and Astronomy

UNH scientists help provide first-ever views of elusive energy explosion

16.11.2018 | Physics and Astronomy

How the gut ‘talks’ to brown fat

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>