Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Novel carbon source sustains deep-sea microorganism communities

18.09.2018

The first in-depth analyses of dissolved organic carbon (DOC) cycling in the Red Sea highlights the important role of migrating shoals of fish in sustaining deep-ocean microorganisms and potentially the global carbon cycle.

The biological carbon pump is a cyclical process by which inorganic carbon from the atmosphere is fixed by marine lifeforms and transported through ocean layers into the deepest waters and ocean sediments. Fish that feed at the surface at night and retreat to the mesopelagic zone (200 to 1000 meters depth) by day were thought to influence carbon cycling, but the extent of their contribution has never been explored.


This echogram section displays the acoustic data showing the vertical and temporal distribution of fish within a 24-hour cycle. Contouring represents the presence (orange) and absence (white) of fish within the water column. Fish are retreating to 400 and 600 meters depth during the day and spending time in the upper 200 meters at night. The almost vertical lines show the fish swimming down at sunrise and up at sunset.

Credit: © 2018 KAUST

Now, Maria Calleja and Xosé Anxelu Morán at KAUST's Red Sea Research Center, and coworkers, demonstrate the impact of this daily migration on the vertical movement of carbon in the Red Sea and how it fuels the metabolism of single-celled heterotrophic prokaryotes belonging to the domains Bacteria and Archaea.

"In a previous study, our co-authors Anders Røstad and Stein Kaartvedt discovered a community of fish in the Red Sea that migrate every night from around 550 meters depth to the surface waters to feed1," says Calleja. "We wondered how this fish migration might affect the microbial community inhabiting the same depths. Our two projects sought to clarify this by collecting data from a single Red Sea sampling site."

The first study examined vertical differences in DOC concentration and the flow of carbon through microbial communities at three specific layers in the water column during the day1. Over eight days, the team monitored features such as DOC consumption, prokaryote growth and community composition in natural water samples taken from the surface, the deep layer where the fish rested during the day, and an intermediate layer at 275 meters.

Bacterial growth efficiency in the deepest layer was significantly higher than previously estimated, "suggesting a labile DOC source--one that is tasty and easily broken down by the bacteria--that helps generate larger cells," explains Calleja. Heterotrophic bacterial communities in the mesopelagic layer were also found to be more active than those in the surface waters.

"Our second paper, led by a former KAUST post-doc who is now at the University of Exeter, Francisca García, followed changes over 24 hours along the whole water column, sampling 12 different depths (from 5 to 700 meters) every two hours2," says Calleja. "We analyzed the dynamics between DOC, bacteria and fish movements during the 24-hour cycle."

The researchers used flow cytometry to analyze microbe cell sizes and community structure at high temporal resolution, showing higher microbial diversity in the mesopelagic zone than expected. These deep microbial communities may be more dynamic than previously thought, thanks to this active carbon transfer of labile DOC by fish.

"If this is happening in the Red Sea, could it be happening in other marine basins and the open ocean? It may have unprecedented implications for the global ocean carbon cycle," notes Calleja.

"These two studies are part of a wider project to determine the impact of this shortcut on global biogeochemical cycling," adds Morán.

Carolyn Unck | EurekAlert!
Further information:
https://discovery.kaust.edu.sa/en/article/644/novel-carbon-source-sustains-deep-sea-microorganism-communities
http://dx.doi.org/10.3389/fmars.2018.00259

More articles from Life Sciences:

nachricht Russian scientists show changes in the erythrocyte nanostructure under stress
22.02.2019 | Lobachevsky University

nachricht How the intestinal fungus Candida albicans shapes our immune system
22.02.2019 | Exzellenzcluster Präzisionsmedizin für chronische Entzündungserkrankungen

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: (Re)solving the jet/cocoon riddle of a gravitational wave event

An international research team including astronomers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has combined radio telescopes from five continents to prove the existence of a narrow stream of material, a so-called jet, emerging from the only gravitational wave event involving two neutron stars observed so far. With its high sensitivity and excellent performance, the 100-m radio telescope in Effelsberg played an important role in the observations.

In August 2017, two neutron stars were observed colliding, producing gravitational waves that were detected by the American LIGO and European Virgo detectors....

Im Focus: Light from a roll – hybrid OLED creates innovative and functional luminous surfaces

Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.

The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...

Im Focus: Regensburg physicists watch electron transfer in a single molecule

For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.

The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...

Im Focus: University of Konstanz gains new insights into the recent development of the human immune system

Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens

Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...

Im Focus: Transformation through Light

Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light

When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Global Legal Hackathon at HAW Hamburg

11.02.2019 | Event News

The world of quantum chemistry meets in Heidelberg

30.01.2019 | Event News

Our digital society in 2040

16.01.2019 | Event News

 
Latest News

JILA researchers make coldest quantum gas of molecules

22.02.2019 | Physics and Astronomy

Understanding high efficiency of deep ultraviolet LEDs

22.02.2019 | Materials Sciences

Russian scientists show changes in the erythrocyte nanostructure under stress

22.02.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>