U of T study finds that global warming changes organic matter in soil, which may result in changes in atmosphere

Friday, December 5, 2008 9:45:00 AM

Research News

New research shows that we should also be looking to the ground, not just the sky, to see where climate change could have its most perilous impact on life on Earth.

In a recent study led by Dr. Myrna Simpson, Associate Professor in the Department of Physical and Environmental Sciences at U of T Scarborough, it was found that global warming actually changes the molecular structure of organic matter in soil. 

"Soil contains more than twice the amount of carbon than does the atmosphere, yet, until now, scientists haven't examined this significant carbon pool closely," said Dr. Simpson. "Through our research, we've sought to determine what soils are made up of at the molecular level and whether this composition will change in a warmer world."

Soil organic matter is what makes dirt fertile and able to support plant life - both of which are especially important for agriculture. Organic matter retains water in the soil and prevents erosion. Natural processes of decomposition of soil organic matter provide plants and microbes with the energy source and water they need to grow and carbon is released into the atmosphere as a by-product of this process. Warming temperatures are expected to speed up this process, which will increase the amount of CO2 that is transferred to the atmosphere.

The research team used a NMR (nuclear magnetic resonance) facility - the only NMR facility in Canada specifically dedicated to environmental research - to gain a detailed view of soil's molecular structure and reactivity. An outdoor field experiment behind the Scarborough campus was also used to ensure natural ecosystem processes were preserved. Electrodes warmed the test soil between three and six degrees through winter and summer seasons, over a 14-month period.

Findings of the study will be published in the journal Nature Geoscience.

For more information, please visit: http://www.utsc.utoronto.ca/~msimpson/

(This is an edited excerpt of an article found at http://www.news.utoronto.ca.)