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 Scientists on the road to discovering impact of urban road dust
18.01.2018 | University of Alberta

nachricht Gran Chaco: Biodiversity at High Risk
17.01.2018 | Humboldt-Universität zu Berlin

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: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>