DOI: 10.1016/j.foreco.2016.05.002
Scopus记录号: 2-s2.0-84966356836
论文题名: Disturbance, tree mortality, and implications for contemporary regional forest change in the Pacific Northwest
作者: Reilly M.J. ; Spies T.A.
刊名: Forest Ecology and Management
ISSN: 0378-1127
出版年: 2016
卷: 374 起始页码: 102
结束页码: 110
语种: 英语
英文关键词: Disturbance
; Fire
; Insects
; Pacific Northwest
; Regional forest dynamics
; Tree mortality
Scopus关键词: Biodiversity
; Dynamics
; Fires
; Population statistics
; Vegetation
; Disturbance
; Insects
; Pacific Northwest
; Regional forests
; Tree mortality
; Forestry
; biodiversity
; demography
; disturbance
; forest dynamics
; forest fire
; forest management
; insect
; mortality
; regional planning
; structural change
; tree
; vegetation cover
; Oregon
; Pacific Northwest
; United States
; Washington [United States]
; Hexapoda
英文摘要: Tree mortality is an important demographic process and primary driver of forest dynamics, yet there are relatively few plot-based studies that explicitly quantify mortality and compare the relative contribution of endogenous and exogenous disturbances at regional scales. We used repeated observations on 289,390 trees in 3673 1 ha plots on U.S. Forest Service lands in Oregon and Washington to compare distributions of mortality rates among natural disturbances and vegetation zones from the mid-1990s to mid-2000s, a period characterized by drought, insect outbreaks, and large wildfires. Endogenous disturbances (e.g. pathogens, insects) were pervasive but operated at relatively low levels of mortality (<2.5%/yr) that rarely exceeded 5%/yr. Exogenous disturbances (e.g. fire, wind, landslides, avalanches) were less common and operated mostly at intermediate levels of mortality (5-25%/yr) indicative of partial-stand-replacement events. Stand-replacing mortality rates (≥25%/yr) comprised a third of all exogenous disturbance events, occurring almost exclusively in fires. Fires were rare in wet vegetation zones and most rates were <2.5%/yr and associated with endogenous processes. Mortality rates in dry vegetation zones revealed a different set of dynamics including a more variable role of background mortality and greater proportions of mortality associated with fire and insects at partial- and stand-replacing levels. Mortality rates in early and middle stages of stand development were low compared to published rates, but rates >1%/yr in over half of the plots in late and old-growth stages corroborate previous findings of elevated mortality during the same period and indicate the potential for pervasive structural change across all vegetation zones. Partial- and stand-replacing fire were associated with most mortality, but affected a relatively small proportion of dry vegetation zones (3.1-7.1% and 2.1-5.1%, respectively). These disturbances have likely affected regional biodiversity through the creation of early seral habitat, increased within-stand heterogeneity, and restored some aspects of historical fire regimes, but there is a need to better understand corresponding structural and compositional changes. We demonstrate the variability in the drivers, magnitude, and extent of mortality across a biophysically diverse region and highlight the need to incorporate and characterize the effects of mortality at intermediate levels to develop a more comprehensive understanding of regional forest dynamics. © 2016 Elsevier B.V.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/64861
Appears in Collections: 影响、适应和脆弱性
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作者单位: Department of Forest Ecosystems and Society, College of Forestry, Oregon State University, Corvallis, OR, United States; USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR, United States
Recommended Citation:
Reilly M.J.,Spies T.A.. Disturbance, tree mortality, and implications for contemporary regional forest change in the Pacific Northwest[J]. Forest Ecology and Management,2016-01-01,374