Navigation Links
Ocean microbe communities changing, but long-term environmental impact is unclear

CORVALLIS, Ore. As oceans warm due to climate change, water layers will mix less and affect the microbes and plankton that pump carbon out of the atmosphere but researchers say it's still unclear whether these processes will further increase global warming or decrease it.

The forces at work are enormous and the stakes huge, said Oregon State University scientists in an article to be published Friday in the journal Science.

But inadequate ocean monitoring and lack of agreement on how to assess microbial diversity has made it difficult to reach a consensus on what the future may hold, they said.

"We're just beginning to understand microbial diversity in the oceans and what that may mean to the environment," said Stephen Giovannoni, an OSU professor of microbiology. "However, a large portion of the carbon emitted from human activities ends up in the oceans, which with both their mass of water and biological processes act as a huge buffer against climate change. These are extremely important issues."

The interest is growing, scientists say, because nearly half of the world's photosynthesis is contributed by microbial plankton, and the process of marine carbon production and consumption is much faster than on land. A turnover of terrestrial plant biomass takes 15 years, they say, while marine turnover takes just six days.

As the ocean surface warms, evidence shows that it will become more "stratified," or confined to layers that mix less than they did in the past. This should reduce overall ocean productivity, Giovannoni said, but so little is known about the effect on ocean microbes that the implication for carbon sequestration and global warming is less clear.

Some OSU research on routine seasonal changes of microbes in the Sargasso Sea of the Atlantic Ocean suggests that different and specialized microbial communities can become more dominant when water warms.

As warmer oceans become a more long-term and global phenomenon, researchers need to know more about these microbes, and whether their behavior will amplify or reduce atmospheric carbon and the greenhouse effect.

It could be either, Giovannoni said.

"Some warming of surface waters may reduce carbon sequestration, which could cause a feedback loop to increase global warming," Giovannoni said.

"Other forces, what we call the microbial carbon pump, could cause carbon to sink into the deep ocean and be segregated from the atmosphere for thousands of years," he said. "We know both of these processes exist, but which one will become dominant is unpredictable, because we know so little about ocean microbes."

It was only two decades ago that OSU scientists discovered SAR11, an ocean microbe and the smallest free-living cell known, but one that's now understood to dominate life in the oceans, thrives where most other cells would die and plays a huge role in carbon cycling on Earth.

Microbial action also surprised scientists just recently, Giovannoni noted, when specific microbe populations surged following the Gulf Coast oil spill and cleaned up much of the oil faster than many thought possible. And some plans to "fertilize" the ocean and sequester atmospheric carbon through marine phytoplankton growth have been put on hold, he said, because it just isn't certain what would happen.

To reduce that uncertainty, Giovannoni advocates more aggressive development and implementation of marine microbial monitoring technology around the world, to add to what scientists can already learn from study of satellite images. And the field is so new, he said, that many researchers are not even comparing the same types of data or standardizing the tools they use to assess microbial diversity a problem that needs to be addressed.

Dramatic advances in DNA sequencing in recent years, Giovannoni said, should also help researchers unravel the ocean microbe mystery.

Contact: Stephen Giovannoni
Oregon State University

Related biology news :

1. Ocean warming causes elephant seals to dive deeper
2. Are nuisance jellyfish really taking over the worlds oceans?
3. Broadcast study of ocean acidification to date helps scientists evaluate effects on marine life
4. Unprecedented, man-made trends in oceans acidity
5. Sensing the deep ocean
6. Researchers assess radioactivity released to the ocean from the Fukushima nuclear facility
7. Submarine springs offer preview of ocean acidification effects on coral reefs
8. Mid-ocean creatures control light to avoid becoming snacks
9. Ocean temperatures can predict Amazon fire season severity
10. Seaweed records show impact of ocean warming
11. Prehistoric greenhouse data from ocean floor could predict earths future, MU study finds
Post Your Comments:
(Date:11/12/2015)... Nov. 11, 2015   Growing need for ... tools has been paving the way for use ... of discrete analytes in clinical, agricultural, environmental, food ... predominantly used in medical applications, however, their adoption ... due to continuous emphasis on improving product quality ...
(Date:11/9/2015)... , Nov. 9, 2015  Synaptics Inc. (NASDAQ: ... today announced broader entry into the automotive market with ... match the pace of consumer electronics human interface innovation. ... are ideal for the automotive industry and will be ... Europe , Japan ...
(Date:10/29/2015)... Va. , Oct. 29, 2015 Daon, ... today that it has released a new version of ... customers in North America have ... IdentityX v4.0 also includes a FIDO UAF certified ... are already preparing to activate FIDO features. These customers ...
Breaking Biology News(10 mins):
(Date:11/30/2015)... Md. , Nov. 30, 2015  Northwest Biotherapeutics ... company developing DCVax® personalized immune therapies for solid tumor ... adding an additional independent director, and the Company welcomes ... of allegations in a recent anonymous internet report on ... both initiatives. Linda Powers stated, "We ...
(Date:11/30/2015)... N.J. and PETACH TIKVAH, Israel ... (NASDAQ: BCLI ), a leading developer of adult ... wholly-owned subsidiary, Brainstorm Cell Therapeutics Ltd., has been awarded an ... Office of the Chief Scientist (OCS). This grant, the ... Brainstorm for 2015 activities to approximately $1.8 million (approximately NIS7 ...
(Date:11/27/2015)... 2015 /PRNewswire/--  Mallinckrodt plc (NYSE: MNK ), ... has closed the sale of its global contrast media ... Euronext) in a transaction valued at approximately $270 million. ... a total of approximately 1,000 employees spread across the ... Louis area. This entire workforce and the ...
(Date:11/27/2015)... , November 27, 2015 ... Growing popularity of companion diagnostics is one ... biomarkers market with pharmaceutical companies and diagnostic ... diagnostic tests. . ... Complete report on global cancer biomarkers market ...
Breaking Biology Technology: