Breaking Barriers Building Bridges: - ERI Library - Northern Arizona ...

18Fire fighters hold a defensive fire line as the Rodeo-Chediski fire burns at night. The Rodeo-Chediski Fire burned468,638 acres in east-central Arizona in 2002. It was the largest wildfire in Arizona’s recorded history until theWallow Fire (538,049 acres burned) in 2011. Photo courtesy of the Apache-Sitgreaves National ForestIn describing the attributes of restored ecosystem, the authorsof the SER Primer use the term, “reference ecosystems.” This termdescribes a model that is based on scientific and other observationsof ecosystem conditions and processes in the historic past and/or inrelatively undisturbed contemporary ecosystems similar to the onebeing restored (Swetnam et al. 1999, Egan and Howell 2001). Sucha historical ecology model can be used to make decisions about whatprocesses and/or species need to be restored, and to assess the progressor success of a restoration project. The idea of reference ecosystems isclosely linked to the concepts of evolutionary environment and range ofhistoric or natural variability—the evolutionary environment developingover a long time span (typically thousands of years) during which speciesevolve and co-evolve with other species and various natural processes(e.g., fire, insects, diseases) under variable environmental conditions.This evolutionary pathway produced resilient evolutionary habitats thatallow the species and processes to exist at varying, but relatively stable