Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rethinking connection between soil as a carbon reservoir and global warming

06.10.2011
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 the humus decreases, additional CO2 gets into the atmosphere. A research team headed by the University of Zurich has now discovered that the soil environment determines humus depletion, which means the question as to how soils respond to global climate change needs to be re-addressed.

Soils store three times as much carbon as plants and the atmosphere. Soil organic matter such as humus plays a key role in the global carbon cycle as it stores huge amounts of carbon and thus counters global warming. Consequently, the Kyoto Protocol permits the signatory countries to count soils and forests against greenhouse gas emissions as so-called carbon sinks.

Exactly why some soil organic matter remains stable for thousands of years while other soil organic matter degrades quickly and releases carbon, however, is largely unknown. The explanatory models used thus far assume that the degradation rate depends on the molecular structures of the soil organic matter. An international team of 14 researchers headed by Michael Schmidt, a professor of soil science and biogeography at the University of Zurich, has now revealed that numerous other factors affect the degradation rate of soil organic matter in an article published in «Nature».

Soil environment determines degradation rate of humus
«The degradation speed isn’t determined by the molecular structure of the dead plant debris, but by the soil environment in which the degradation takes place,» says Schmidt, summing up the new results. For instance, the physical isolation of the molecules, whether the molecules in the soil are protected by mineral or physical structures and soil moisture influence the degradation rate of soil organic matter. Furthermore, the researchers are able to show that, contrary to the scientific consensus, there is no humic matter in the soil and this should therefore not be used for models.
New experiments and models needed
As Professor Schmidt explains, the findings need to be used for new experiments and models. In doing so, it is not only the first few centimeters of the soil that should be examined, as has been the case up to now, but rather the full top two to three meters. In their article, the researchers make various suggestions as to how the models for forecasting the response of soils to changes in the climate, vegetation and land use might be improved.

Moreover, the new results cast a critical light on bioengineering experiments with plants containing high amounts of lignin or plant charcoal (biochar), with which more carbon is supposed to be stored in the soil in the long run.

Literature:
Michael W. I. Schmidt, Margaret S. Torn, Samuel Abiven, Thorsten Dittmar, Georg Guggenberger, Ivan A. Janssens, Markus Kleber, Ingrid Kögel-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, in: Nature, 6 October, 2011, DOI: 10.1038/nature10386

Nathalie Huber | idw
Further information:
http://www.uzh.ch

More articles from Earth Sciences:

nachricht NASA eyes Pineapple Express soaking California
24.02.2017 | NASA/Goddard Space Flight Center

nachricht 'Quartz' crystals at the Earth's core power its magnetic field
23.02.2017 | Tokyo Institute of Technology

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>