Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Agricultural soil erosion not contributing to global warming

26.10.2007
Agricultural soil erosion is not a source of carbon dioxide to the atmosphere, according to research published online today (25 October) in Science. The study was carried out by an international team led by researchers at the Katholieke Universiteit Leuven, Belgium, the University of Exeter, UK, and the University of California, Davis.

The researchers developed a new method to establish the net effect of erosion on exchanges of carbon between the soil and the atmosphere. They found that in landscapes subject to soil erosion, erosion acts like a conveyor belt, excavating subsoil, passing it through surface soils and burying it in hill-slope hollows.

During its journey, the soil absorbs carbon from plant material and this becomes buried within the soil in depositional areas. Erosion, therefore, leads to more carbon being removed from the atmosphere than is emitted, creating what can be described as a ‘sink’ of atmospheric carbon.

The team found that these sinks of CO2 represent the equivalent of around 1.5% of annual fossil fuel emissions. This finding challenges previous assessments that erosion represents an additional source of carbon to the atmosphere equivalent to adding 13% to annual fossil fuel emissions. The finding also challenges the opposite notion that erosion is currently offsetting fossil fuel emissions by more than 10%.

Dr Kristof Van Oost of the Katholieke Universiteit Leuven said: “There is an on-going debate on the link between agricultural soil erosion and the carbon cycle. Academics on one side have argued that soil erosion causes considerable levels of carbon emissions and on the other that erosion is actually offsetting fossil fuel emissions. Our research clearly shows that neither of these is the case.”

This new insight into the effect of erosion on the carbon cycle is essential for sound management of agricultural soils. If previous assessments that erosion causes a high level of carbon emissions to the atmosphere had been correct, then erosion control could have been used to offset fossil fuel emissions. If the assessment that erosion created a very large sink of atmospheric carbon had been correct then the environmental benefits of erosion control would have had to be set against the loss of the sink.

“Our results show that erosion control should be pursued for its environmental and agronomic benefits but should not be used to offset fossil fuel emissions,” said Professor Tim Quine of the University of Exeter. “Soil erosion is not the silver bullet for offsetting the ever-increasing emission of CO2 to the atmosphere.”

The researchers used a by-product of nuclear weapons testing (caesium-137) that is present throughout the world to track the movement of soil around the agricultural landscape. This allowed them to predict how much carbon would be expected to be found in areas of soil erosion and deposition. By comparing these predictions with measured amounts of carbon in 1400 soil profiles they could identify which soils had acted as sinks of carbon and which had acted as sources. They were also able to establish the fraction of carbon that was replaced at sites of erosion, which enabled them to calculate the effect of erosion on the global carbon cycle.

Sarah Hoyle | EurekAlert!
Further information:
http://www.exeter.ac.uk

More articles from Ecology, The Environment and Conservation:

nachricht Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF

nachricht Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>