scholarly journals Influence of fire disturbance and biophysical heterogeneity on pre‐settlement ponderosa pine and mixed conifer forests

Ecosphere ◽  
2016 ◽  
Vol 7 (11) ◽  
Author(s):  
James D. Johnston ◽  
John D. Bailey ◽  
Christopher J. Dunn
Keyword(s):  
Ponderosa Pine ◽  
Fire Disturbance ◽  
Conifer Forests ◽  
Mixed Conifer ◽  
Mixed Conifer Forests

The effects of burn entry and burn severity on ponderosa pine and mixed conifer forests in Grand Canyon National Park

2015 ◽  
Vol 24 (4) ◽  
pp. 495 ◽  
Author(s):  
Anna M. Higgins ◽  
Kristen M. Waring ◽  
Andrea E. Thode
Keyword(s):  
Ponderosa Pine ◽  
National Park ◽  
Forest Type ◽  
Grand Canyon ◽  
Burn Severity ◽  
Conifer Forests ◽  
Mixed Conifer ◽  
Grand Canyon National Park ◽  
White Fir ◽  
Mixed Conifer Forests

Over a century of fire exclusion in frequent-fire ponderosa pine and dry mixed conifer forests has resulted in increased tree densities, heavy surface fuel accumulations and an increase in late successional, fire-intolerant trees. Grand Canyon National Park uses prescribed fires and wildfires to reduce fire hazard and restore ecosystem processes. Research is needed to determine post-fire vegetation response thus enabling future forest succession predictions. Our study focussed on the effects of burn entry and burn severity on species composition and regeneration in two forest types: ponderosa pine with white fir encroachment and dry mixed conifer. We found no difference in tree composition and structure in a single, low-severity burn compared with unburned areas in the white fir encroachment forest type. We found no white fir seedlings or saplings in a second-entry, low-severity burn in the white fir encroachment forest type. Second-entry burns were effective in reducing white fir densities in the white fir encroachment forest type. There was significant aspen regeneration following high-severity fire in the dry mixed conifer forest type. This research suggests that repeated entries and an increase in burn severity may be necessary for prescribed fire or wildfire to be effective in meeting management objectives.

scholarly journals Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America

PLoS ONE ◽  
2016 ◽  
Vol 11 (5) ◽  
pp. e0147688 ◽  
Author(s):  
Jens T. Stevens ◽  
Hugh D. Safford ◽  
Malcolm P. North ◽  
Jeremy S. Fried ◽  
Andrew N. Gray ◽  
...  
Keyword(s):  
North America ◽  
Ponderosa Pine ◽  
Forest Inventory ◽  
Fire Regimes ◽  
Stand Age ◽  
Western North America ◽  
Conifer Forests ◽  
Mixed Conifer ◽  
Mixed Conifer Forests

Late Holocene geomorphic record of fire in ponderosa pine and mixed-conifer forests, Kendrick Mountain, northern Arizona, USA

2011 ◽  
Vol 20 (1) ◽  
pp. 125 ◽  
Author(s):  
Sara E. Jenkins ◽  
Carolyn Hull Sieg ◽  
Diana E. Anderson ◽  
Darrell S. Kaufman ◽  
Philip A. Pearthree
Keyword(s):  
Debris Flow ◽  
Ponderosa Pine ◽  
Debris Flows ◽  
Late Holocene ◽  
Conifer Forests ◽  
Fire Behaviour ◽  
Mixed Conifer ◽  
Northern Arizona ◽  
Mixed Conifer Forests ◽  
Steep Slopes

Long-term fire history reconstructions enhance our understanding of fire behaviour and associated geomorphic hazards in forested ecosystems. We used 14C ages on charcoal from fire-induced debris-flow deposits to date prehistoric fires on Kendrick Mountain, northern Arizona, USA. Fire-related debris-flow sedimentation dominates Holocene fan deposition in the study area. Radiocarbon ages indicate that stand-replacing fire has been an important phenomenon in late Holocene ponderosa pine (Pinus ponderosa) and ponderosa pine–mixed conifer forests on steep slopes. Fires have occurred on centennial scales during this period, although temporal hiatuses between recorded fires vary widely and appear to have decreased during the past 2000 years. Steep slopes and complex terrain may be responsible for localised crown fire behaviour through preheating by vertical fuel arrangement and accumulation of excessive fuels. Holocene wildfire-induced debris flow events occurred without a clear relationship to regional climatic shifts (decadal to millennial), suggesting that interannual moisture variability may determine fire year. Fire-debris flow sequences are recorded when (1) sufficient time has passed (centuries) to accumulate fuels; and (2) stored sediment is available to support debris flows. The frequency of reconstructed debris flows should be considered a minimum for severe events in the study area, as fuel production may outpace sediment storage.

Sign in / Sign up

Export Citation Format

Share Document