The Failing Freezer: How Soil Microbes Affect Global Climate

Lead an international collaboration to study the influence of soil microbes on global climate: Virginia Rich in the UA department of soil, water and environmental science and the UA Institute of the Environment (left) and Scott Saleska of the department of ecology and evolutionary biology. (Photo: Beatriz Verdugo/UANews)
Lead an international collaboration to study the influence of soil microbes on global climate: Virginia Rich in the UA department of soil, water and environmental science and the UA Institute of the Environment (left) and Scott Saleska of the department of ecology and evolutionary biology. (Photo: Beatriz Verdugo/UANews)
The U.S. Department of Energy has awarded $3.9 million to an international collaboration led by University of Arizona ecologists Scott Saleska and Virginia Rich to study how microbes release greenhouse gases as they access nutrients in thawing permafrost soils under the influence of a warmer climate. 
 
The project aims to explain how microbe-driven processes influence climate change, and in what ways climate-driven changes, such as changes in soil chemistry and changes in plant communities, feed back on those microbial processes. The team hopes the results will help solve what Saleska, a professor in the UA Department of Ecology and Evolutionary Biology, calls the "big biology problem" in climate change. 
"Even if we know how much fossil fuel is burned, we don't know how much climate is actually going to change because we don't know how biology as a whole – animals, plants, microbes – will respond," he said. "How do microbial processes affect the environment? These relationships still are mostly a black box."
 
One third of the world's carbon is locked away in permafrost soils around the world – areas where the ground stays frozen year-round. In many areas, though, warmer temperatures have started to change things; soils that used to be frozen year-round have begun to thaw during certain times of the year while others experience longer seasonal thawing or thaw down to deeper depths than they used to. 
 
"As the system warms, we see the seasonal thaw go deeper and deeper, and eventually, everything thaws at some point over the year and the permafrost is going away," Saleska explained. "This is already happening and if we don’t take steps to avoid climate change, we expect this type of ecosystem to be gone within the next 100 to 200 years."
 
This peat permafrost region is a sentinel ecosystem of global change, according to Rich, who is a faculty member in the UA Department of Soil, Water and Environmental Science and, together with Saleska, an affiliate of the UA Institute of the Environment
 
"This habitat literally is at the leading edge of climate change, because we can observe how it is being pushed northwards," Rich said. "We can see changes with our own eyes and within a matter of years. Because they happen so quickly there, our science has immediate payoff and very real implications that apply on a global scale."
 
Read the rest of this September 23, 2013 UANews article at the link below.
Date released: 
Oct 2 2013
Contact: 
Virginia Rich