Featured Research

from universities, journals, and other organizations

At least 200,000 tons of oil and gas from Deepwater Horizon spill consumed by Gulf bacteria

Date:
September 11, 2012
Source:
University of Rochester
Summary:
Researchers have found that, over a period of five months following the disastrous 2010 Deepwater Horizon explosion and oil spill, naturally-occurring bacteria that exist in the Gulf of Mexico consumed and removed at least 200,000 tons of oil and natural gas that spewed into the deep Gulf from the ruptured well-head.

Oil slick.
Credit: John Kessler

Researchers from the University of Rochester and Texas A&M University have found that, over a period of five months following the disastrous 2010 Deepwater Horizon explosion and oil spill, naturally-occurring bacteria that exist in the Gulf of Mexico consumed and removed at least 200,000 tons of oil and natural gas that spewed into the deep Gulf from the ruptured well head.

The researchers analyzed an extensive data set to determine not only how much oil and gas was eaten by bacteria, but also how the characteristics of this feast changed with time.

"A significant amount of the oil and gas that was released was retained within the ocean water more than one-half mile below the sea surface. It appears that the hydrocarbon-eating bacteria did a good job of removing the majority of the material that was retained in these layers," said co-author John Kessler of the University of Rochester.

The results published this week in Environmental Science and Technology include the first measurements of how the rate at which the bacteria ate the oil and gas changed as this disaster progressed, information that is fundamental to understanding both this spill and predicting the behavior of future spills.

Kessler noted: "Interestingly, the oil and gas consumption rate was correlated with the addition of dispersants at the wellhead. While there is still much to learn about the appropriateness of using dispersants in a natural ecosystem, our results suggest it made the released hydrocarbons more available to the native Gulf of Mexico microorganisms."

Their measurements show that the consumption of the oil and gas by bacteria in the deep Gulf had stopped by September 2010, five months after the Deepwater Horizon explosion. "It is unclear if this indicates that this great feast was over by this time or if the microorganisms were simply taking a break before they start on dessert and coffee" said Kessler. "Our results suggest that some (about 40%) of the released hydrocarbons that once populated these layers still remained in the Gulf post September 2010, so food was available for the feast to continue at some later time. But the location of those substances and whether they were biochemically transformed is unknown."

Previous studies of the Deepwater Horizon spill had shown that the oil and gas were trapped in underwater layers, or "plumes," and that the bacteria had begun consuming the oil and gas. By using a more extensive data set, the researchers were able to measure just how many tons of hydrocarbons released from the spill had been removed in the deep Gulf waters. The team's research suggests that the majority of what once composed these large underwater plumes of oil and gas was eaten by the bacteria.

Professor John Kessler, recently appointed as Associate Professor in the Department of Earth and Environmental Sciences of the University of Rochester, worked with graduate research assistant Mengran Du at Texas A&M University to analyze over 1300 profiles of oxygen dissolved in the Gulf of Mexico water spanning a period of four months and covering nearly 30,000 square miles.

The researchers calculated how many tons of oil and gas had been consumed and at what rate by first measuring how much oxygen had been removed from the ocean. Mengran Du explained that "when bacteria consume oil and gas, they use up oxygen and release carbon dioxide, just as humans do when we breathe. When bacteria die and decompose, that uses up still more oxygen. Both these processes remove oxygen from the water." Du added that it is this lower oxygen level that the researchers could measure and use as an indicator of how much oil and gas had been removed by microorganisms and at what rate.

The work was supported by the National Science Foundation with additional contributions from the National Oceanic and Atmospheric Administration, the Sloan Foundation, BP/the Gulf of Mexico Research Initiative, and the Chinese Scholarship Council.


Story Source:

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


Journal Reference:

  1. Mengran Du, John D. Kessler. Assessment of the Spatial and Temporal Variability of Bulk Hydrocarbon Respiration Following the Deepwater Horizon Oil Spill. Environmental Science & Technology, 2012; 120910170030009 DOI: 10.1021/es301363k

Cite This Page:

University of Rochester. "At least 200,000 tons of oil and gas from Deepwater Horizon spill consumed by Gulf bacteria." ScienceDaily. ScienceDaily, 11 September 2012. <www.sciencedaily.com/releases/2012/09/120911125315.htm>.
University of Rochester. (2012, September 11). At least 200,000 tons of oil and gas from Deepwater Horizon spill consumed by Gulf bacteria. ScienceDaily. Retrieved April 23, 2014 from www.sciencedaily.com/releases/2012/09/120911125315.htm
University of Rochester. "At least 200,000 tons of oil and gas from Deepwater Horizon spill consumed by Gulf bacteria." ScienceDaily. www.sciencedaily.com/releases/2012/09/120911125315.htm (accessed April 23, 2014).

Share This



More Earth & Climate News

Wednesday, April 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

California Drought Is Good News for Gold Prospectors

California Drought Is Good News for Gold Prospectors

AFP (Apr. 22, 2014) — For months California has suffered from a historic drought. The lack of water is worrying for farmers and ranchers, but for gold diggers it’s a stroke of good fortune. With water levels low, normally inaccessible areas are exposed. Duration: 01:57 Video provided by AFP
Powered by NewsLook.com
Raw: MN Lakes Still Frozen Before Fishing Opener

Raw: MN Lakes Still Frozen Before Fishing Opener

AP (Apr. 22, 2014) — With only three weeks until Minnesota's fishing opener, many are wondering if the ice will be gone. Some of the Northland lakes are still covered by up to three feet of ice, causing concern that just like last year, the lakes won't be ready. (April 22) Video provided by AP
Powered by NewsLook.com
Scientists Warn Of Likely El Niño Event This Year

Scientists Warn Of Likely El Niño Event This Year

Newsy (Apr. 22, 2014) — With Pacific ocean water already showing signs of warming, the NOAA says there's about a 66 percent chance the event will begin before November. Video provided by Newsy
Powered by NewsLook.com
Is North Korea Planning Nuclear Test #4?

Is North Korea Planning Nuclear Test #4?

Newsy (Apr. 22, 2014) — South Korean officials say North Korea is preparing to conduct another nuclear test, but is Pyongyang just bluffing this time? Video provided by Newsy
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