Featured Research

from universities, journals, and other organizations

How soil carbon responds to climate change: Scientists work to improve predictions

Date:
October 5, 2011
Source:
Max Planck Institute for Biogeochemistry
Summary:
Soils store more carbon than the atmosphere and living plants. But scientists don't know why some organic compounds persist for centuries or even thousands of years in soils, while others quickly decompose. This longstanding mystery is addressed in a review by an international team of scientists.

Soil profile.
Credit: Image courtesy of Max Planck Institute for Biogeochemistry

Soils store more carbon than the atmosphere and living plants. But scientists don't know why some organic compounds persist for centuries or even thousands of years in soils, while others quickly decompose.

This longstanding mystery is addressed in a review by the University of Zurich's Michael Schmidt, Susan Trumbore from Max Planck Institute of Biogeochemistry in Jena and an international team of scientists that is published in the Oct. 6 issue of the journal Nature. The researchers suggest ways to improve the ability to predict how soil carbon responds to climate change as well as land use and vegetation change.

For many years, scientists thought that organic matter persists in soil because some of it forms very complex molecular structures that were too difficult for organisms to break down.

In their Nature review, however, Schmidt and colleagues point out how recent advances, from imaging the molecules in soils to experiments that track decomposition of specific compounds, show this view to be mistaken. For example, the major forms of organic matter in soils are in the forms of simple biomolecules, rather than large macromolecules. Charred residues from fire provide a possible exception, but even these have been shown to decompose.

If molecular structure is not causing organic molecules to persist, what is? The team contends that the average time carbon resides in soil is a property of the interactions between organic matter and the surrounding soil ecosystem. Factors like physical isolation, recycling, or protection of molecules by minerals or physical structures like aggregates, or even unfavorable local temperature or moisture conditions, can all play a role in reducing the probability that a given molecule will decompose.

Although soils are teeming with bacteria (there are approximately 40 million cells in a gram of soil), they typically occupy less than 1% of the available volume, and are usually clustered in 'hot spots'. In some situations where microbial populations are sparse, for example in deep soils or far from roots, it may just require a long time for suitable conditions to arise that allow a molecule to be broken down. In other locations, freezing temperatures may inhibit microbial action.

Why is this important? Currently, models we use to predict how global soil carbon will respond to climate change include little mechanistic understanding and instead use simple factors like temperature dependence that indicate acceleration of decomposition in a warmer world. This assumes that temperature is the major limitation to decomposition, whereas other factors may dominate.

The decomposition-warming feedback predicts large soil carbon losses and an amplification of global warming, but in fact the authors argue this approach is too simplistic. In the Nature review, the scientists make several suggestions where current improvements in understanding could be built into models, improving our ability to predict how soil carbon responds not only to climate but to land use or vegetation change.


Story Source:

The above story is based on materials provided by Max Planck Institute for Biogeochemistry. Note: Materials may be edited for content and length.


Journal Reference:

  1. Michael W. I. Schmidt, Margaret S. Torn, Samuel Abiven, Thorsten Dittmar, Georg Guggenberger, Ivan A. Janssens, Markus Kleber, Ingrid K๖gel-Knabner, Johannes Lehmann, David A. C. Manning, Paolo Nannipieri, Daniel P. Rasse, Steve Weiner, Susan E. Trumbore. Persistence of soil organic matter as an ecosystem property. Nature, 2011; 478 (7367): 49 DOI: 10.1038/nature10386

Cite This Page:

Max Planck Institute for Biogeochemistry. "How soil carbon responds to climate change: Scientists work to improve predictions." ScienceDaily. ScienceDaily, 5 October 2011. <www.sciencedaily.com/releases/2011/10/111005172128.htm>.
Max Planck Institute for Biogeochemistry. (2011, October 5). How soil carbon responds to climate change: Scientists work to improve predictions. ScienceDaily. Retrieved August 22, 2014 from www.sciencedaily.com/releases/2011/10/111005172128.htm
Max Planck Institute for Biogeochemistry. "How soil carbon responds to climate change: Scientists work to improve predictions." ScienceDaily. www.sciencedaily.com/releases/2011/10/111005172128.htm (accessed August 22, 2014).

Share This




More Plants & Animals News

Friday, August 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) — An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Terrifying City-Dwelling Spiders Are Bigger And More Fertile

Terrifying City-Dwelling Spiders Are Bigger And More Fertile

Newsy (Aug. 21, 2014) — According to a new study, spiders that live in cities are bigger, fatter and multiply faster. Video provided by Newsy
Powered by NewsLook.com
Lost Brain Cells To Blame For Sleep Problems Among Seniors

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Newsy (Aug. 21, 2014) — According to a new study, elderly people might have trouble sleeping because of the loss of a certain group of neurons in the brain. Video provided by Newsy
Powered by NewsLook.com
Ramen Health Risks: The Dark Side of the Noodle

Ramen Health Risks: The Dark Side of the Noodle

AP (Aug. 21, 2014) — South Koreans eat more instant ramen noodles per capita than anywhere else in the world. But American researchers say eating too much may increase the risk of diabetes, heart disease and stroke. (Aug. 21) 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:

More Coverage


Rethinking Connection Between Soil as a Carbon Reservoir and Global Warming

Oct. 5, 2011 — The soil plays a key role in the ecosystem, economy and global carbon cycle. After the oceans, the humus is the largest carbon reservoir. If humus decreases, additional CO2 ... read more
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