DOI: 10.1016/j.foreco.2014.06.032
Scopus记录号: 2-s2.0-84904490622
论文题名: Fire severity, size, and climate associations diverge from historical precedent along an ecological gradient in the Pinaleño Mountains, Arizona, USA
作者: O'Connor C.D. ; Falk D.A. ; Lynch A.M. ; Swetnam T.W.
刊名: Forest Ecology and Management
ISSN: 0378-1127
出版年: 2014
卷: 329 起始页码: 264
结束页码: 278
语种: 英语
英文关键词: Climate
; Elevation gradient
; ENSO
; Fire history
; PDSI
; Spatial reconstruction
Scopus关键词: Climatology
; Ecology
; Forestry
; Fuels
; Loading
; Climate
; Elevation gradient
; ENSO
; Fire history
; PDSI
; Spatial reconstruction
; Fires
; climate effect
; coniferous forest
; environmental gradient
; fire management
; fuelwood
; grazing
; historical record
; mixed forest
; precipitation (climatology)
; reconstruction
; stand structure
; temporal variation
; trend analysis
; wildfire
; Climates
; Ecology
; Forest Fires
; Fuels
; Arizona
; Pinaleno Mountains
; United States
英文摘要: In recent decades fire size and severity have been increasing in high elevation forests of the American Southwest. Ecological outcomes of these increases are difficult to gauge without an historical context for the role of fire in these systems prior to interruption by Euro-American land uses. Across the gradient of forest types in the Pinaleño Mountains, a Sky Island system in southeast Arizona that experienced two relatively large high-severity fires in the last two decades, we compared fire characteristics and climate associations before and after the onset of fire exclusion to determine the degree of similarity between past and recent fires. We use a gridded fire scar and demography sampling network to reconstruct spatially explicit estimates of fire extent and burn severity, as well as climate associations of fires from individual site to landscape scales from 1640 to 2008 C.E. We found that patterns of fire frequency, size, and severity were relatively stable for at least several centuries prior to 1880. A combination of livestock grazing and active fire suppression after circa 1880 led to (1) a significant reduction in fire spread but not fire ignition, (2) a conversion of more than 80% of the landscape from a frequent, low to mixed-severity fire regime to an infrequent mixed to high-severity fire regime, and (3) an increase in fuel continuity within a mid-elevation zone of dry mixed-conifer forest, resulting in increased opportunities for surface and crown fire spread into higher elevation mesic forests. The two most recent fires affecting mesic forests were associated with drought and temperature conditions that were not exceptional in the historical record but that resulted in a relative proportion of high burn severity up to four times that of previous large fires. The ecological effects of these recent fires appear to be more severe than any fire in the reconstructed period, casting uncertainty upon the recovery of historical species composition in high-severity burn patches. Significant changes to the spatial pattern, frequency, and climate associations of spreading fires after 1880 suggest that limits to fuel loading and fuel connectivity sustained by frequent fire have been removed. Coinciding factors of high fuel continuity and fuel loading, projected lengthening of the fire season, and increased variability in seasonal precipitation suggest that large high-severity fires, especially in mixed-conifer forests, will become the predominant fire type without aggressive actions to reduce fuel continuity and restore fire-resilient forest structure and species composition. © 2014 The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/65833
Appears in Collections: 影响、适应和脆弱性
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作者单位: University of Arizona, School of Natural Resources and the Environment, 325 Biosciences East Building, Tucson, AZ 85721, United States; U.S. Forest Service, Rocky Mountain Research Station, 1215 E. Lowell St., Tucson, AZ 85721, United States; University of Arizona, Laboratory of Tree-Ring Research, 1215 E. Lowell St., Tucson, AZ 85721, United States
Recommended Citation:
O'Connor C.D.,Falk D.A.,Lynch A.M.,et al. Fire severity, size, and climate associations diverge from historical precedent along an ecological gradient in the Pinaleño Mountains, Arizona, USA[J]. Forest Ecology and Management,2014-01-01,329