Abstract
This study examined the effects of two types of parent material, sandstone and limestone, on the response of vegetation growth after the 1990 Dude Fire in central Arizona. The operating hypothesis of the study was that, given the right conditions, severe wildfire can trigger vegetation type conversion. Overall, three patterns emerged: (1) oak density increased by 413% from unburned sites to burned sites, with the highest densities occurring on sandstone soils; (2) weeping lovegrass (Eragrostis curvula Nees), a very aggressive non-native grass species seeded after the fire, now makes up 81% of the total herbaceous cover in the burned area; and (3) bare ground cover is 150% higher and litter cover is 50% lower in the burned area. Soil analysis was not definitive enough to differentiate impacts between parent materials however it was useful in quantifying the long-term impact of the fire on soils. The results of this study support the idea that catastrophic fire events can trigger vegetation type conversion and that perennial, non-native species used in rehabilitation efforts can persist within the ecosystem for long periods of time. Hence, the recovery period needed for the Dude Fire site to revert back to a pine-oak dominated forest could be on the scale of many decades to centuries.
Highlights
Using historical records, stand reconstruction, and dendrochronology to recreate natural fire regimes, it is believed the average fire return interval within ponderosa pine forests of the southwest was around2–47 years [1]
Within the past century, fire suppression has decreased the occurrence of low severity fire across the landscape leading to greater fuel loading and an increase in high severity fire events
From the multi-response permutation procedure (MRPP), we found that ponderosa pine and juniper had higher densities on unburned sites, while the oak and manzanita had higher densities in the burned area
Summary
Stand reconstruction, and dendrochronology to recreate natural fire regimes, it is believed the average fire return interval within ponderosa pine forests of the southwest was around2–47 years [1]. Stand reconstruction, and dendrochronology to recreate natural fire regimes, it is believed the average fire return interval within ponderosa pine forests of the southwest was around. In addition to thinning the forests, these typically low severity fire events promoted fire resistant traits within the ponderosa pine species (Pinus ponderosa Douglas ex Loudon) These traits include thick bark to protect against heat damage, resinous needles, and flammable litter, which acts to decrease competition from seedlings found in the understory, while leaving the overstory intact [1,2]. It is estimated that in 1876, the last year of a frequent-fire regime, the average forest density in ponderosa pine dominate stands in the southwest U.S was 60 trees·ha−1.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
