Tillage shows very little impact on carbon sequestration

November 18, 2014, INRA

Reducing or eliminating tillage is one of the farming practices most frequently touted to improve carbon sequestration in soil. A new study by INRA and Arvalis-Institut du Végétal turns this paradigm on its head. This study, the result of a rigorous experiment conducted in the Ile-de-France region, shows that after a period of 41 years, three tillage methods led to similar carbon sequestration outcomes. However, variations were apparent over time based on climate conditions.

At a time when and increased CO2 emissions due to human activities are major concerns, was thought to hold the key to increasing in cultivated soil. Numerous studies confirmed that reducing or even eliminating tillage could improve sequestration. This recommendation, supported by the Intergovernmental Panel on Climate Change (IPCC1), was made based on a number of results obtained mainly in North America. However, recent reviews of scientific literature2 have highlighted methodological weaknesses regarding much of the research, challenging the importance of tillage on possible carbon sequestration.

INRA researchers analysed the results of experiments carried out in France by Arvalis-Institut du Végétal over a period of 20 to 41 years in Boigneville (Ile-de-France region) using an original approach that included calculating carbon stores over a greater depth (0–60cm) and monitoring carbon stores over time. They were able to demonstrate that carbon sequestration in the soil for three tillage methods (annual tillage, minimum tillage and no-tillage) were identical after 41 years of these practices being continually implemented. Minimum tillage did indeed increase carbon sequestration at the surface (0–10 cm), but reduced it at greater depths (10–30 cm).

By analysing changes in carbon stores over time, the researchers showed that reduced tillage leads to phases of carbon capture and release that depend on . Dry years promote carbon sequestration in conjunction with minimal tillage, while years with significant rainfall lead to carbon being released when compared to tilled soil.

Carbon sequestration rates were not constant but rather positive or negative. Over the long term, the effectiveness of tillage methods depends on climate conditions, especially rainfall. Reduced tillage can impact ecosystem services other than climate regulation, but does not appear to be effective for carbon sequestration in humid temperate climates.

Explore further: ARS scientists help improve soil carbon calculations

More information: Angers D.A., Eriksen-Hamel N.S. (2008) Full-inversion tillage and organic carbon distribution in soil profiles: a meta-analysis. Soil Sci. Soc. Am. J. 72: 1370-1374.

Luo Z., Wang E., Sun O.J. (2010) Can no-tillage stimulate carbon sequestration in agricultural soils? A meta-analysis of paired experiments. Agric. Ecosyst. Environ. 139: 224-231.

Virto I., Barré P., Burlot A., Chenu C., 2012. Carbon input differences as the main factor explaining the variability in soil organic C storage in no-tilled compared to inversion tilled agrosystems. Biogeochemistry 108: 17-26.

Long-term effect of contrasted tillage and crop management on soil carbon dynamics during 41 years. Agriculture, Ecosystems and Environment, 15 avril
2014. dx.doi.org/10.1016/j.agee.2014.02.014

Changes in soil carbon and nitrogen following tillage conversion in a long-term experiment in Northern France. Agriculture, Ecosystems and Environment, 20 mars 2013. dx.doi.org/10.1016/j.agee.2013.01.012

Related Stories

US greenhouse gas emissions and capture, regionally

August 12, 2010

A new report, Agriculture's Role in Greenhouse Gas Emissions and Capture, commissioned by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, examines the evidence for greenhouse ...

Farming commercial miscanthus

August 31, 2011

An article in the current issue of Global Change Biology Bioenergy examines the carbon sequestration potential of Miscanthus plantations on commercial farms.

Recommended for you

Japan to make crater on asteroid to get underground samples

March 18, 2019

Japan's space agency said Monday that its Hayabusa2 spacecraft will follow up last month's touchdown on a distant asteroid with another risky mission—dropping an explosive on the asteroid to make a crater and then collect ...

Bright X-ray galactic nuclei

March 18, 2019

All massive galaxies are believed to host supermassive black holes (SMBH) at their centers that grow by accreting mass from their environment. The current picture also imagines that the black holes grow in size as their host ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.