The dirt on greenhouse gas emissions

Published: April 7, 2016

The dirt on greenhouse gas emissions

Contact(s): Layne Cameron , Phil Robertson

While the use of fossil fuels such as coal, gas and oil is the largest contributor to emissions of greenhouse gases into the atmosphere, there are other factors as well.

One of the biggest is soil, or specifically, land use.

New research in the current issue of Nature, describes how changes in land-use practices can help reduce the levels of greenhouse gases such as carbon dioxide, nitrous oxide and methane in the atmosphere.

Agricultural soils in particular can be made to capture even more greenhouse gases than they emit, making them not just climate neutral but “net mitigating,” said Phil Robertson, University Distinguished Professor of plant, soil and microbial sciences and director of MSU’s Kellogg Biological Station Long-Term Ecological Research program.

“We know from research that game-changing technology is available to do this, but farmers are rational beings and their first priority is paying bills, not climate mitigation,” said Robertson, who was a co-author on the study. “Farmers don’t change their cropping practices to favor greenhouse gas mitigation because it could generally cost more in terms of labor, equipment and soil management time.”

Finding the right incentives could be a key to making improvements, agrees Keith Paustian, Colorado State University professor of soil and crop sciences, who led the study.

“What needs to change is how we incentivize new land-use strategies for farmers, ranchers and producers,” he said.

Emerging research and information technology developments offer promise in paving the way for policies that can make use of the large greenhouse mitigation potential available through improved land use and management.

One example is an online tool designed to help farmers and ranchers understand how their practices impact their carbon footprint. COMET-Farm, which stands for CarbOn Management and Evaluation Tool, was developed by CSU and the USDA and helps producers estimate their greenhouse gas footprint and evaluate alternative management practices.

Paustian noted that these new approaches and new tools will not only allow for increased engagement on the part of farmers and ranchers but also offer a chance for industry to become more actively involved in land-use issues.

“Land use is as much a social issue as it is an environmental issue,” said Paustian. “We need to develop the right policies and incentives for industry, and we need to do so by marshaling our scientific research and expertise.”

Among the report’s other recommendations are generating more high-quality data on land-use impacts on greenhouse gas emissions and greater engagement through education and outreach with the land users themselves. The full study can be found in Nature here.

Other authors on this study include: Johannes Lehmann, Atkinson Center for a Sustainable Future, Cornell University; Stephen Ogle, CSU Department of Ecosystem Science and Sustainability; David Reay, School of Geosciences, University of Edinburgh; and Pete Smith, Institute of Biological and Environmental Sciences, University of Aberdeen.

This research was funded by the National Science Foundation.

The full paper can be accessed at: