May 5, 2009

Plants can influence wildfires

U.S. scientists say they've determined a warmer climate might produce dry vegetation, and the types of plants in an area can mitigate wildfire occurrences.

Lawrence Livermore National Laboratory scientist Tom Brown, Philip Higuera of Montana State University and their colleagues looked at the direct and indirect impacts of millennial scale climate change on fire occurrence in the south-central Brooks Range in Alaska by analyzing sediments found in the bottom of lakes.

They said they determined historical changes in fire frequencies coincided with changes in the type of vegetation in the area, more so than to rising temperatures alone.

If all we did was look at rising temperatures and ignore the vegetation in the area, that wouldn't be a good predictor of the likelihood of wildfires in a particular region, Brown said. There's a complex relationship between fuels and climate. Vegetation can have a profound impact on fire occurrences that are opposite or independent of climate's direct influence on fire.

The study that included Ben Clegg, Linda Brubaker and Feng Sheng Hu is reported in the journal Ecological Monographs.