Featured Research

from universities, journals, and other organizations

Greenhouse gas likely altering ocean foodchain: Atmospheric CO2 has big consequences for tiny bacteria

Date:
July 2, 2013
Source:
University of Southern California
Summary:
Climate change may be weeding out the bacteria that form the base of the ocean's food chain, selecting certain strains for survival, according to a new study.

Colony of trichodesmium bacteria roughly the size of the head of a pin.
Credit: Eric Webb/USC

Climate change may be weeding out the bacteria that form the base of the ocean's food chain, selecting certain strains for survival, according to a new study.

In climate change, as in everything, there are winners and losers. As atmospheric carbon dioxide levels and temperature rise globally, scientists increasingly want to know which organisms will thrive and which will perish in the environment of tomorrow.

The answer to this question for nitrogen-fixing cyanobacteria (bacteria that obtain energy through photosynthesis, or "blue-green algae") turns out to have implications for every living thing in the ocean. Nitrogen-fixing is when certain special organisms like cyanobacteria convert inert -- and therefore unusable -- nitrogen gas from the air into a reactive form that the majority of other living beings need to survive. Without nitrogen fixers, life in the ocean could not survive for long.

"Our findings show that CO2 has the potential to control the biodiversity of these keystone organisms in ocean biology, and our fossil fuel emissions are probably responsible for changing the types of nitrogen fixers that are growing in the ocean," said David Hutchins, professor of marine environmental biology at the USC Dornsife College of Letters, Arts and Sciences and lead author of an article about this research that appeared in Nature Geoscience on June 30.

"This may have all kinds of ramifications for changes in ocean food chains and productivity, even potentially for resources we harvest from the ocean such as fisheries production," Hutchins said.

Hutchins and his team studied two major groups of nitrogen-fixing cyanobacteria: Trichodesmium, which forms large floating colonies big enough to see with the naked eye and makes vast "blooms" in the open ocean, and Crocosphaera, which is also very abundant but is a single-celled, microscopic organism.

Previous research showed that these two types of cyanobacteria should be some of the biggest "winners" of climate change, thriving in high CO2 levels and warmer oceans. However, those previous studies only examined one or two strains of the organisms.

That's where USC's unique resource comes into play -- the university is home to a massive culture library of strains and species of the organisms assembled by USC Associate Professor Eric Webb.

Using the culture library, the team was able to show that some strains grow better at CO2 levels not seen since the start of the Industrial Revolution, while others will thrive in the future "greenhouse" Earth.

"It's not that climate change will wipe out all nitrogen fixers; we've shown that there's redundancy in nature's system. Rather, increasing atmospheric carbon dioxide changes specifically which nitrogen fixers are likely to thrive," Hutchins said. "And we're not entirely certain how that will change the ocean of tomorrow."


Story Source:

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


Journal Reference:

  1. David A. Hutchins, Fei-Xue Fu, Eric A. Webb, Nathan Walworth, Alessandro Tagliabue. Taxon-specific response of marine nitrogen fixers to elevated carbon dioxide concentrations. Nature Geoscience, 2013; DOI: 10.1038/ngeo1858

Cite This Page:

University of Southern California. "Greenhouse gas likely altering ocean foodchain: Atmospheric CO2 has big consequences for tiny bacteria." ScienceDaily. ScienceDaily, 2 July 2013. <www.sciencedaily.com/releases/2013/07/130702141506.htm>.
University of Southern California. (2013, July 2). Greenhouse gas likely altering ocean foodchain: Atmospheric CO2 has big consequences for tiny bacteria. ScienceDaily. Retrieved September 19, 2014 from www.sciencedaily.com/releases/2013/07/130702141506.htm
University of Southern California. "Greenhouse gas likely altering ocean foodchain: Atmospheric CO2 has big consequences for tiny bacteria." ScienceDaily. www.sciencedaily.com/releases/2013/07/130702141506.htm (accessed September 19, 2014).

Share This



More Earth & Climate News

Friday, September 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Wildfires in CA Burn Forest Asunder

Raw: Wildfires in CA Burn Forest Asunder

AP (Sep. 18, 2014) An out-of-control Northern California wildfire has nearly 2,800 people from their homes as it continues to grow, authorities said Thursday. Authorities said a man has been arrested on suspicion of arson for starting the fire on Saturday. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Raw: Elephant Undergoes Surgery in Tbilisi Zoo

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

AP (Sep. 18, 2014) Grand the elephant has successfully undergone surgery to remove a portion of infected tusk at Tbilisi Zoo in Georgia. British veterinary surgeons used an electric drill to extract the infected piece. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
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