Episode 6 - Regime Change: History of Fire Ecology in NevadaOctober 15th, 2021
From the Ponderosa Pine-covered mountains in the Eastern Great Basin to the arid Mojave Desert and all the sagebrush and grass in between, Nevada’s ecosystems are diverse. Fire behaves differently across these regions, both historically and today. The guests on the latest episode of the Living With Fire Podcast “Regime Change: History of fire ecology in Nevada,” explain why fire is an important process in Nevada, how scientists study fire, and why understanding the history of fire can give scientists and land managers useful clues to help them manage landscapes today.
The term “fire regime” refers to the history of fire in a given location—specifically the frequency, size and intensity of fires in that location over a period of time. Fire regimes in Nevada can be difficult to study. In areas where there are trees, scientists can use tree rings and look for fire scars that can tell them when fires occurred. However, Ali Urza, research ecologist with the U.S. Forest Service, explained the challenges of studying the history of fire in sagebrush ecosystems, when you cannot rely on tree rings for help. “And in desert ecosystems. We don't have those high-precision records of fire so our understanding of historic fire regimes is a lot more limited. And there's a lot of debate over what historic fire regimes looked like in desert ecosystems,” said Urza.
Researchers often have to rely on other clues, like traditional knowledge from Native American tribes to figure out what landscapes might have looked like pre-European settlement. For example, Matt Brooks, supervisory research ecologist with the Western Ecological Research Center, explains on the podcast that “in a landscape like the Mojave where water is at a premium and really water dictates whether human habitation is possible even today, regular burning around spring sites would increase spring flow. We know that today and it’s clearly happened in the past.”
Although there is debate among researchers about what historic fire regimes might have looked like in Nevada, there seems to be agreement on a few points. First, fire will always have a role to play in Nevada ecosystems. Second, for as long as humans have existed on the land, they have contributed to the relative “health” of ecosystems and our actions or inaction have consequences.