Featured Research

from universities, journals, and other organizations

Soil microbes alter DNA in response to warming

Date:
January 16, 2014
Source:
Georgia Institute of Technology
Summary:
Scientists studying grasslands in Oklahoma have discovered that an increase of 2 degrees Celsius in the air temperature above the soil creates significant changes to the microbial ecosystem underground. Compared to a control group with no warming, plants in the warmer plots grew faster and higher, which put more carbon into the soil as the plants senesce. The microbial ecosystem responded by altering its DNA to enhance the ability to handle the excess carbon.

As scientists forecast the impacts of climate change, one missing piece of the puzzle is what will happen to the carbon in the soil and the microbes that control the fate of this carbon as the planet warms.

Scientists studying grasslands in Oklahoma have discovered that an increase of 2 degrees Celsius in the air temperature above the soil creates significant changes to the microbial ecosystem underground. Compared to a control group with no warming, plants in the warmer plots grew faster and higher, which put more carbon into the soil as the plants senesce. The microbial ecosystem responded by altering its DNA to enhance the ability to handle the excess carbon.

"What we conclude from this study is the warming has an effect on the soil ecosystem," said Kostas Konstantinidis, an assistant professor who holds the Carlton S. Wilder Chair in Environmental Engineering at the Georgia Institute of Technology. "It does appear that the microbes change genetically to take advantage of the opportunity given to them."

The study was published online Dec. 27, 2013, in the journal Applied and Environmental Microbiology. The research was sponsored by the Department of Energy, and involved collaboration with several universities, including the University of Oklahoma.

The findings are the culmination of a 10-year study that seeks to understand how the most intricate ecosystem in nature -- soil -- will respond to climate change.

A single gram of soil is home to a billion bacterial cells, representing at least 4,000 different species. In comparison, the human gut is home to at least 10 times fewer different species of bacteria. Scientists have little idea what microbes in the soil do, how they do it, or how they respond to changes in their environment, Konstantinidis said. This limits the predictive capabilities of climate models.

"In models of climate change it is a black box what happens to the carbon in soil," Konstantinidis said. "One reasons that models of climate change have such big room for variation is because we don't understand the microbial activities that control carbon in the soil."

Complicating matters, 99.9 percent of the microbes in the soil cannot be grown in the lab, so scientists must study them where they live. The molecular and genomic techniques to do so are a specialty of the Konstantinidis lab.

The researchers traveled to the Kessler Farm Field Laboratory in McClain County, Oklahoma, where they conducted their study on grassland soils, which had been abandoned for agriculture use for more than 20 years. The scientists warmed plots of soil with radiators set a few feet above the ground for 10 consecutive years. They warmed these plots 2 degrees Celsius, which many climate models forecast as the global temperature increase over the next 50 years.

The researchers took samples of the plants, measured the carbon content and the number of microbes in the soil, and documented any changes in the warm plots versus the control plots. The team also extracted DNA from the soil and identified the genetic composition and changes of the microbes living there.

The plants in the warm plots grew better and higher. As the plants started senescing at the end of the season, their higher biomass led to more carbon in the soil. However, the microbial communities had increased their rate of respiration, which converted soil organic carbon to carbon dioxide (CO2), so the total carbon in the warm and control soils was similar.

The microbial communities in the warm soils had undergone significant changes during the decade of the experiment, which facilitated their higher respiration rate. For instance, the study of the DNA of the microbes revealed found that the microbial communities of the warm plots had more genes related to carbon respiration than the microbes in the control plots.

"That was consistent with the idea that the additional carbon from the plants was all respired and converted to CO2," Konstantinidis said. "We saw that the warmed microbial community was more efficient in eating up the plant-derived soil carbon and making it CO2."

The research team plans to do similar studies in other agricultural soils and in colder areas, such as Alaska tundra permafrost ecosystems, where there is more organic carbon in the soil.

"There are complex interactions between plants and microbes and we need to understand them better to have a more predictive understanding of what's going on," Konstantinidis said. "This is the first study trying to do that, but we are not close to the complete understanding yet."


Story Source:

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


Journal Reference:

  1. C. Luo, L. M. Rodriguez-R, E. R. Johnston, L. Wu, L. Cheng, K. Xue, Q. Tu, Y. Deng, Z. He, J. Z. Shi, M. M. Yuan, R. A. Sherry, D. Li, Y. Luo, E. A. G. Schuur, P. Chain, J. M. Tiedje, J. Zhou, K. T. Konstantinidis. Soil microbial community responses to a decade of warming as revealed by comparative metagenomics.. Applied and Environmental Microbiology, 2013; DOI: 10.1128/AEM.03712-13

Cite This Page:

Georgia Institute of Technology. "Soil microbes alter DNA in response to warming." ScienceDaily. ScienceDaily, 16 January 2014. <www.sciencedaily.com/releases/2014/01/140116130447.htm>.
Georgia Institute of Technology. (2014, January 16). Soil microbes alter DNA in response to warming. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2014/01/140116130447.htm
Georgia Institute of Technology. "Soil microbes alter DNA in response to warming." ScienceDaily. www.sciencedaily.com/releases/2014/01/140116130447.htm (accessed September 30, 2014).

Share This



More Plants & Animals News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. Video provided by Newsy
Powered by NewsLook.com
California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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