Featured Research

from universities, journals, and other organizations

Carbon-sequestering ocean plants may cope with climate changes over the long run

Date:
August 26, 2013
Source:
San Francisco State University
Summary:
A year-long experiment on tiny ocean organisms called coccolithophores suggests that the single-celled algae may still be able to grow their calcified shells even as oceans grow warmer and more acidic in Earth's near future. The study stands in contrast to earlier studies suggesting that coccolithophores would fail to build strong shells in acidic waters.

This is an image of the coccolithophore, Emiliania huxleyi, taken by lead author Ina Benner using the San Francisco State University FE-Scanning Electron Microscope.
Credit: Ina Benner

A year-long experiment on tiny ocean organisms called coccolithophores suggests that the single-celled algae may still be able to grow their calcified shells even as oceans grow warmer and more acidic in Earth's near future.

The study stands in contrast to earlier studies suggesting that coccolithophores would fail to build strong shells in acidic waters. The world's oceans are expected to become more acidic as human activities pump increasing amounts of carbon dioxide into Earth's atmosphere.

But after the researchers raised one strain of the Emiliania huxleyi coccolithorphore for over 700 generations, which took about 12 months, under high temperature and acidified conditions that are expected for the oceans 100 years from now, the organisms had no trouble producing their plated shells.

"At least in this experiment with one coccolithophore strain, when we combined higher levels of CO2 with higher temperatures, they actually did better in terms of calcification." said Jonathon Stillman, associate professor of biology at San Francisco State University, who along with Ed Carpenter, professor of biology, and Tomoko Komada, associate professor of chemistry, led a team of researchers at the University's Romberg Tiburon Center for Environmental Studies. The research was performed by postdoctoral scientist Ina Benner, masters students Rachel Diner and Dian Li and postdoctoral scientist Stephane Lefebvre.

Coccolithophores sequester oceanic carbon by incorporating it into their shells, which provide ballast to speed the sinking of carbon to the deep sea. These little organisms are central to the global carbon cycle, a role that could be disrupted if rising levels of atmospheric carbon dioxide and warming temperatures interfere with their ability to grow their calcified shells.

In previous experiments, the same SF State researchers found that the same strain of coccolithophores grown for hundreds of generations under cool and acidified water conditions grew less shell than those growing under current ocean conditions. In a short-term study by other researchers that examined the combined effects of higher temperatures and acidification, the same strain also had smaller shells under warmer and acidified conditions. However, results from this new long-term experiment suggest that this strain of coccolithophores may have the capacity to adapt to warmer and more acidic seas if given adequate time.

Stillman said the study underscores the importance of assessing multiple climactic factors and their impact on these organisms over a long time, to understand how they may cope with future oceanic environmental changes.

"We don't know why some strains might calcify more in the future, when others might calcify less," he said. Recent evidence indicates that the genetic diversity among coccolithophores in nature may hold part of the answer as to which strains and species might be "pre-adapted for future ocean conditions," Stillman added.

While these results indicate that coccolithophore calcification might increase under future ocean conditions, the researchers say that it's still unclear "whether, or how, such changes might affect carbon export to the deep sea."

The researchers received another surprise when they used recently developed genomic approaches to compare the expression of genes related to calcification in coccolithophores grown under current and future seawater conditions. "We really expected to see a lot of genes known to be involved in calcification to change significantly in the cells that thrived under high temperature and high acidity," Stillman said, "given their increased levels of calcification."

But the researchers found no significant changes in the expression of genes known to be involved in calcification from prior studies comparing strains with dramatically different calcification levels. It could be that these genes work as a sort of "on-off switch" for calcification, Stillman suggested. There may be other genes at work that control calcification in more subtle ways, affecting the degree of calcification.


Story Source:

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


Journal Reference:

  1. Ina Benner, Rachel E. Diner, Stephane C. Lefebvre, Dian Li, Tomoko Komada, Edward J. Carpenter, and Jonathon H. Stillman. Emiliania huxleyi increases calcification but not expression of calcification-related genes in long-term exposure to elevated temperature and pCO2. Phil. Trans. R. Soc. B., 2013 DOI: 10.1098/rstb.2013.0049

Cite This Page:

San Francisco State University. "Carbon-sequestering ocean plants may cope with climate changes over the long run." ScienceDaily. ScienceDaily, 26 August 2013. <www.sciencedaily.com/releases/2013/08/130826100118.htm>.
San Francisco State University. (2013, August 26). Carbon-sequestering ocean plants may cope with climate changes over the long run. ScienceDaily. Retrieved September 19, 2014 from www.sciencedaily.com/releases/2013/08/130826100118.htm
San Francisco State University. "Carbon-sequestering ocean plants may cope with climate changes over the long run." ScienceDaily. www.sciencedaily.com/releases/2013/08/130826100118.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