Study quantifies climate benefits of sustainable land use
Switching to more sustainable forms of land use management could significantly boost the carbon-storing capacity of the planet’s soils — by up to 8 billion tons of greenhouse gases, scientists reported in a new study. Previous research shows that soils currently lock away around 2.4 trillion tonnes of greenhouse gases, which are stored underground as stable organic matter.
The measures identified by the researchers include growing crops with deeper root systems and using charcoal-based composts. Widespread adoption sustainable land use practices and and application of best available technologies could help soils store up to 80 percent of greenhouse gases released by fossil fuel combustion, the researchers calculated.
The study team included scientists with the Universities of Aberdeen and Edinburgh, who said the role of soils in combating climate change has been overlooked, partly because it’s hard to get accurate measurements. Implementing such measures would require close cooperation among scientists, policymakers and land users. More resources should be provided to help reduce the environmental impact of farms, the scientists concluded.
“In the fight to avoid dangerous climate change in the 21st century we need heavyweight allies,” said Professor Dave Reay, of the University of Edinburgh’s School of GeoSciences. One of the most powerful is right beneath our feet. Soils are already huge stores of carbon, and improved management can make them even bigger.”
Grassroots initiatives could help overcome cultural resistance to changing agricultural habits, including tools like the Cool Farm Tool, a free online greenhouse gas calculator for crop growers.
The study, published in the journal Nature, received funding from the Natural Environment Research Council. The research was carried out in collaboration with Colorado State University, Cornell University and Michigan State University.
“Soils have probably been overlooked as you cannot see the large carbon stocks they contain, whereas you can see trees growing and getting bigger,” said Professor Pete Smith, of the University of Aberdeen. “It is also difficult to easily measure changes in soil carbon as changes are slow and we are trying to measure a small change against a large background.
“But after International Year of Soils in 2015, and the French Government’s initiative to increase soil carbon stocks to tackle climate change agreed at the Paris climate summit last December, soils are now firmly on the climate change agenda,” he concluded.