Featured Research

from universities, journals, and other organizations

The tiniest greenhouse gas emitters: Climate feedbacks from decomposition by soil microbes less dire than previously thought

Date:
April 7, 2014
Source:
International Institute for Applied Systems Analysis
Summary:
Climate feedbacks from decomposition by soil microbes are one of the biggest uncertainties facing climate modelers. A new study shows that these feedbacks may be less dire than previously thought.

Microbe model.
Credit: Tina Kaiser

Climate feedbacks from decomposition by soil microbes are one of the biggest uncertainties facing climate modelers. A new study from the International Institute for Applied Systems Analysis (IIASA) and the University of Vienna shows that these feedbacks may be less dire than previously thought.

The dynamics among soil microbes allow them to work more efficiently and flexibly as they break down organic matter -- spewing less carbon dioxide into the atmosphere than previously thought, according to a new study published in the journal Ecology Letters.

"Previous climate models had simply looked at soil microbes as a black box," says Christina Kaiser, lead author of the study who conducted the work as a post-doctoral researcher at IIASA. Kaiser, now an assistant professor at the University of Vienna, developed an innovative model that helps bring these microbial processes to light.

Microbes and the climate

"Soil microbes are responsible for one of the largest carbon dioxide emissions on the planet, about six times higher than from fossil fuel burning," says IIASA researcher Oskar Franklin, one of the study co-authors. These microbes release greenhouse gases such as carbon dioxide and methane into the atmosphere as they decompose organic matter. At the same time, Earth's trees and other plants remove about the same amount of carbon dioxide from the atmosphere through photosynthesis.

As long as these two fluxes remain balanced, everything is fine.

But as the temperature warms, soil conditions change and decomposition may change. And previous models of soil decomposition suggest that nutrient imbalances such as nitrogen deficiency would lead to increased carbon emissions. "This is such a big flux that even small changes could have a large effect," says Kaiser. "The potential feedback effects are considerably high and difficult to predict."

Diversity does the trick

How exactly microorganisms in the soil and litter react to changing conditions, however, remains unclear. One reason is that soil microbes live in diverse, complex communities, where they interact with each other and rely on one another for breaking down organic matter.

"One microbe species by itself might not be able to break down a complex substrate like a dead leaf," says Kaiser. "How this system reacts to changes in the environment doesn't depend just on the individual microbes, but rather on the changes to the numbers and interactions of microbe species within the soil community."

To understand these community processes, Kaiser and colleagues developed a computer model that can simulate complex soil dynamics. The model simulates the interactions between 10,000 individual microbes within a 1mm by 1mm square. It shows how nutrients, which influence microbial metabolism, affect these interactions, and change the soil community and thereby the decomposition process.

Previous models had viewed soil decomposition as a single process, and assumed that nutrient imbalances would lead to less efficient decomposition and hence greater greenhouse gas emissions. But the new study shows that, in fact, microbial communities reorganize themselves and continue operating efficiently -- emitting far less carbon dioxide than previously predicted.

"This model is a huge step forward in our understanding of microbial decomposition, and provides us with a much clearer picture of the soil system," says University of Vienna ecologist Andreas Richter, another study co-author.


Story Source:

The above story is based on materials provided by International Institute for Applied Systems Analysis. Note: Materials may be edited for content and length.


Journal Reference:

  1. Christina Kaiser, Oskar Franklin, Ulf Dieckmann, Andreas Richter. Microbial community dynamics alleviate stoichiometric constraints during litter decay. Ecology Letters, 2014; DOI: 10.1111/ele.12269

Cite This Page:

International Institute for Applied Systems Analysis. "The tiniest greenhouse gas emitters: Climate feedbacks from decomposition by soil microbes less dire than previously thought." ScienceDaily. ScienceDaily, 7 April 2014. <www.sciencedaily.com/releases/2014/04/140407101710.htm>.
International Institute for Applied Systems Analysis. (2014, April 7). The tiniest greenhouse gas emitters: Climate feedbacks from decomposition by soil microbes less dire than previously thought. ScienceDaily. Retrieved September 19, 2014 from www.sciencedaily.com/releases/2014/04/140407101710.htm
International Institute for Applied Systems Analysis. "The tiniest greenhouse gas emitters: Climate feedbacks from decomposition by soil microbes less dire than previously thought." ScienceDaily. www.sciencedaily.com/releases/2014/04/140407101710.htm (accessed September 19, 2014).

Share This



More Plants & Animals News

Friday, September 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Chocolate Museum Opens in Brussels

Chocolate Museum Opens in Brussels

AFP (Sep. 19, 2014) Considered a "national heritage" in Belgium, chocolate now has a new museum in Brussels. In a former chocolate factory, visitors to the permanent exhibition spaces, workshops and tastings can discover derivatives of the cocoa bean. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) 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

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