Thursday, 11 August 2011

Wildfires spur emissions of greenhouse gases from soil

The Summit County Voice reports that an accidental bush fire during a climate change experiment revealed that wildfires can significantly increase the release of the environmentally-damaging gas nitrous oxide, which can, in turn, accelerate climate change.

“Soils are the major source of nitrous oxide in the atmosphere,” said Jamie Brown, graduate student in biological sciences at Northern Arizona University (NAU) and co-author of the study. “So increased soil emissions of nitrous oxide will accelerate global warming.”

Brown worked with other researchers from NAU, Stanford University, the University of Paris and the University of Lyon. Their experiments were based on an experimental grassland which was exposed to simulated and simultaneous environmental changes relating to heat, extra carbon dioxide in the atmosphere, more rain, more nitrogen deposition, and, when part of the experiment accidentally burned, wildfire.

“Alone, the treatments had little influence on nitrous oxide emissions, but what was really surprising was the interaction with wildfire, causing a huge burst of nitrous oxide production,” said NAU professor Bruce Hungate, Brown’s thesis adviser and co-author on the study.

“Increasing wildfire frequency and the changing climate could cause these soil micro-organisms to release more nitrous oxide into the atmosphere, accelerating global warming,” Brown said. Read the full report here.