Featured Research

from universities, journals, and other organizations

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

Date:
February 9, 2012
Source:
Oregon State University
Summary:
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. It could be either, they say.

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.
Credit: © Sergey Galushko / Fotolia

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 published February 10 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.


Story Source:

The above story is based on materials provided by Oregon State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Stephen J. Giovannoni, Kevin L. Vergin. Seasonality in Ocean Microbial Communities. Science, 2012; 335 (6069): 671-676 DOI: 10.1126/science.1198078

Cite This Page:

Oregon State University. "Ocean microbe communities changing, but long-term environmental impact is unclear." ScienceDaily. ScienceDaily, 9 February 2012. <www.sciencedaily.com/releases/2012/02/120209144003.htm>.
Oregon State University. (2012, February 9). Ocean microbe communities changing, but long-term environmental impact is unclear. ScienceDaily. Retrieved July 26, 2014 from www.sciencedaily.com/releases/2012/02/120209144003.htm
Oregon State University. "Ocean microbe communities changing, but long-term environmental impact is unclear." ScienceDaily. www.sciencedaily.com/releases/2012/02/120209144003.htm (accessed July 26, 2014).

Share This




More Earth & Climate News

Saturday, July 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Virginia Governor Tours Tornado Aftermath

Virginia Governor Tours Tornado Aftermath

AP (July 25, 2014) — Virginia Gov. Terry McAuliffe toured the Cherrystone Family Camping and RV Resort on the Chesapeake Bay today, a day after it was hit by a tornado. The storm claimed two lives and injured dozens of others. (July 25) Video provided by AP
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) — Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) — The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Bill Gates: Health, Agriculture Key to Africa's Development

Bill Gates: Health, Agriculture Key to Africa's Development

AFP (July 24, 2014) — Health and agriculture development are key if African countries are to overcome poverty and grow, US software billionaire Bill Gates said Thursday, as he received an honourary degree in Ethiopia. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins