| Registro completo |
| Provedor de dados: |
Ecology and Society
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| País: |
Canada
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| Título: |
Past, Present, and Future Old Growth in Frequent-fire Conifer Forests of the Western United States
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| Autores: |
Abella, Scott R.; Public Lands Institute and School of Life Sciences, University of Nevada-Las Vegas; Scott.Abella@unlv.edu
Covington, W. Wallace; Ecological Restoration Institute; Northern Arizona University School of Forestry; wally.covington@nau.edu
Lentile, Leigh B.; Department of Forest Resources, University of Idaho; lentile@uidaho.edu
Morgan, Penelope; Department of Forest Resources, University of Idaho; pmorgan@uidaho.edu
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| Data: |
2007-11-16
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| Ano: |
2007
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| Palavras-chave: |
Ecological restoration
Evolutionary environment
Mixed conifer
Management
Pinus jeffreyi
Pinus ponderosa
Range of variability
Sequoia giganteum
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| Resumo: |
Old growth in the frequent-fire conifer forests of the western United States, such as those containing ponderosa pine (Pinus ponderosa), Jeffrey pine (P. jeffreyi), giant sequoia (Sequioa giganteum) and other species, has undergone major changes since Euro-American settlement. Understanding past changes and anticipating future changes under different potential management scenarios are fundamental to developing ecologically based fuel reduction or ecological restoration treatments. Some of the many changes that have occurred in these forests include shifts from historically frequent surface fire to no fire or to stand-replacing fire regimes, increases in tree density, increased abundance of fire-intolerant trees, decreases in understory productivity, hydrological alterations, and accelerated mortality of old trees. Although these changes are widespread, the magnitude and causes of changes may vary within and among landscapes. Agents of change, such as fire exclusion or livestock grazing, likely interacted and had multiple effects. For example, historical ranching operations may have altered both fire regimes and understory vegetation, and facilitated institutional fire exclusion through fragmentation and settlement. Evidence exists for large variation in presettlement characteristics and current condition of old growth across this broad forest region, although there are many examples of striking similarities on widely distant landscapes. Exotic species, climate change, unnatural stand-replacing wildfires, and other factors will likely continue to degrade or eradicate old growth in many areas. As a policy of fire exclusion is proving to be unsustainable, mechanical tree thinning, prescribed fire, or wildland fire use will likely be key options for forestalling continued eradication of old growth by severe crown fires. For many practical and societal reasons, the wildland–urban interface may afford some of the most immediate opportunities for re-establishing old growth typical of presettlement forests resistant to crown fires.
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| Tipo: |
Peer-Reviewed article
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| Idioma: |
Inglês
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| Identificador: |
vol12/iss2/art16/
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| Editor: |
Resilience Alliance
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| Formato: |
text/html application/pdf
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| Fonte: |
Ecology and Society; Vol. 12, No. 2 (2007)
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