Research Database
Displaying 81 - 100 of 115
Tamm Review: Management of mixed-severity fire regime forests in Oregon, Washington, and Northern California
Year: 2016
Increasingly, objectives for forests with moderate- or mixed-severity fire regimes are to restore successionally diverse landscapes that are resistant and resilient to current and future stressors. Maintaining native species and characteristic processes requires this successional diversity, but methods to achieve it are poorly explained in the literature. In the Inland Pacific US, large, old, early seral trees were a key historical feature of many young and old forest successional patches, especially where fires frequently occurred. Large, old trees are naturally fire-tolerant, but today are…
Publication Type: Journal Article
REVIEW: Searching for resilience: addressing the impacts of changing disturbance regimes on forest ecosystem services
Year: 2016
The provisioning of ecosystem services to society is increasingly under pressure from global change. Changing disturbance regimes are of particular concern in this context due to their high potential impact on ecosystem structure, function and composition. Resilience-based stewardship is advocated to address these changes in ecosystem management, but its operational implementation has remained challenging. We review observed and expected changes in disturbance regimes and their potential impacts on provisioning, regulating, cultural and supporting ecosystem services, concentrating on…
Publication Type: Journal Article
Changing disturbance regimes, ecological memory, and forest resilience
Year: 2016
Ecological memory is central to how ecosystems respond to disturbance and is maintained by two types of legacies – information and material. Species life-history traits represent an adaptive response to disturbance and are an information legacy; in contrast, the abiotic and biotic structures (such as seeds or nutrients) produced by single disturbance events are material legacies. Disturbance characteristics that support or maintain these legacies enhance ecological resilience and maintain a “safe operating space” for ecosystem recovery. However, legacies can be lost or diminished as…
Publication Type: Journal Article
Managed wildfire effects on forest resilience and water in the Sierra Nevada
Year: 2016
Fire suppression in many dry forest types has left a legacy of dense, homogeneous forests. Such landscapes have high water demands and fuel loads, and when burned can result in catastrophically large fires. These characteristics are undesirable in the face of projected warming and drying in the western US. Alternative forest and fire treatments based on managed wildfire—a regime in which fires are allowed to burn naturally and only suppressed under defined management conditions—offer a potential strategy to ameliorate the effects of fire suppression. Understanding the long-term effects of…
Publication Type: Journal Article
Disturbance, tree mortality, and implications for contemporary regional forest change in the Pacific Northwest
Year: 2016
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.…
Publication Type: Journal Article
Scanning the Future of Wildfire: Resilience Ahead...Whether We Like It or Not?
Year: 2016
The field of so-called “futures research” provides researchers and stakeholders in a given subject area or system a way to map out and plan for alternate possible scenarios of the future. A recent research project supported by the Joint Fire Science Program brought together futures researchers and wildfire specialists to envision what the future holds for wildfire impacts and how the wildfire community may respond to the complex suite of emerging challenges. The consensus of the project’s foresight panel suggests that an era of resilience is ahead: but that this resilience may come either…
Publication Type: Report
U.S. federal fire and forest policy: emphasizing resilience in dry forests
Year: 2016
Current U.S. forest fire policy emphasizes short-term outcomes versus long-term goals. This perspective drives managers to focus on the protection of high-valued resources, whether ecosystem-based or developed infrastructure, at the expense of forest resilience. Given these current and future challenges posed by wildland fire and because the U.S. Forest Service spent >50% of its budget on fire suppression in 2015, a review and reexamination of existing policy is warranted. One of the most difficult challenges to revising forest fire policy is that agency organizations and decision making…
Publication Type: Journal Article
Patterns of conifer regeneration following high severity wildfire in ponderosa pine - dominated forests of the Colorado Front Range
Year: 2016
Many recent wildfires in ponderosa pine (Pinus ponderosa Lawson & C. Lawson) - dominated forests of the western United States have burned more severely than historical ones, generating concern about forest resilience. This concern stems from uncertainty about the ability of ponderosa pine and other co-occurring conifers to regenerate in areas where no surviving trees remain. We collected post-fire conifer regeneration and other data within and surrounding five 11-18 year-old Colorado Front Range wildfires to examine whether high severity burn areas (i.e., areas without surviving trees)…
Publication Type: Journal Article
Tree mortality and structural change following mixed-severity fire in Pseudotsuga forests of Oregon’s western Cascades, USA
Year: 2016
Mixed-severity fires are increasingly recognized as common in Pseudotsuga forests of the Pacific Northwest and may be an important mechanism for developing or maintaining their structural diversity and complexity. Questions remain about how tree mortality varies and forest structure is altered across the disturbance gradient imposed by these fires. Therefore, we sampled live and dead trees at 45–1.0 ha plots, each with four 0.10 ha nested subplots, stratified across an unburned, low, moderate and high-severity fire gradient. Burned plots were primarily sampled 10 and 22 years post-fire,…
Publication Type: Journal Article
Opportunities to utilize traditional phenological knowledge to support adaptive management of social-ecological systems vulnerable to changes in climate and fire regimes
Year: 2016
The field of adaptive management has been embraced by researchers and managers in the United States as an approach to improve natural resource stewardship in the face of uncertainty and complex environmental problems. Integrating multiple knowledge sources and feedback mechanisms is an important step in this approach. Our objective is to contribute to the limited literature that describes the benefits of better integrating indigenous knowledge (IK) with other sources of knowledge in making adaptive-management decisions. Specifically, we advocate the integration of traditional phenological…
Publication Type: Journal Article
Employing resilience in the United States Forest Service
Year: 2016
The concept of resilience has permeated the discourse of many land use and environmental agencies in an attempt to articulate how to develop and implement policies concerned with the social and ecological dimensions of natural disturbances. Several distinct definitions of resilience exist, each with its own concepts, focus and contexts related to land use policy and management. This often makes understanding the inherent objectives of policies and related principles challenging. The United States Forest Service (USFS) is one example where ambiguity and uncertainty surrounding the use of…
Publication Type: Journal Article
Re-envisioning community-wildfire relations in the U.S. West as adaptive governance
Year: 2015
Prompted by a series of increasingly destructive, expensive, and highly visible wildfire crises in human communities across the globe, a robust body of scholarship has emerged to theorize, conceptualize, and measure community-level resilience to wildfires. To date, however, insufficient consideration has been given to wildfire resilience as a process of adaptive governance mediated by institutions at multiple scales. Here we explore the possibilities for addressing this gap through an analysis of wildfire resilience among wildland-urban interface communities in the western region of the…
Publication Type: Journal Article
Enhancing adaptive capacity for restoring fire-dependent ecosystems: the Fire Learning Network’s Prescribed Fire Training Exchanges
Year: 2015
Prescribed fire is a critical tool for promoting restoration and increasing resilience in fire-adapted ecosystems, but there are barriers to its use, including a shortage of personnel with adequate ecological knowledge and operational expertise to implement prescribed fire across multijurisdictional landscapes. In the United States, recognized needs for both professional development and increased use of fire are not being met, often because of institutional limitations. The Fire Learning Network has been characterized as a multiscalar, collaborative network that works to enhance the adaptive…
Publication Type: Journal Article
Spatiotemporal dynamics of recent mountain pine beetle and western spruce budworm outbreaks across the Pacific Northwest Region
Year: 2015
Across the western US, the two most prevalent native forest insect pests are mountain pine beetle (MPB; Dendroctonus ponderosae; a bark beetle) and western spruce budworm (WSB; Choristoneura freemani; a defoliator). MPB outbreaks have received more forest management attention than WSB outbreaks, but studies to date have not compared their cumulative mortality impacts in an integrated, regional framework. The objectives of this study are to: (1) map tree mortality associated with MPB and WSB outbreaks by integrating forest health aerial detection surveys (ADS; 1970–2012), Landsat time series (…
Publication Type: Journal Article
Local Ecological Knowledge and Fire Management: What Does the Public Understand?
Year: 2015
As fire management agencies seek to implement more flexible fire management strategies, local understanding and support for these strategies become increasingly important. One issue associated with implementing more flexible fire management strategies is educating local populations about fire management and identifying what local populations know or do not know related to fire management. This study used survey data from three 2010 wildland fires to understand how ecological knowledge and education level affected fire management perception and understanding. Results indicated that increased…
Publication Type: Journal Article
Fuel and vegetation trends after wildfire in treated versus untreated forests
Year: 2015
Increasing size and severity of wildfires have led to increased interest in managing forests for resiliency to future disturbances. Comparing and contrasting treated versus untreated stands through multiple growing seasons postfire provide an opportunity to understand processes driving responses and can guide management decisions regarding resiliency. In treated and untreated forests, we compared fire effects 2‐10 growing seasons following fire on 3 different fires in New Mexico and Arizona. We estimated understory cover, standing crop, fuel loading, and basal area in (1) lop, pile, burn; (2…
Publication Type: Journal Article
Wildland fire management: insights from a foresight panel
Year: 2015
Wildland fire management faces unprecedented challenges in the 21st century: the increasingly apparent effects of climate change, more people and structures in the wildland-urban interface, growing costs associated with wildfire management, and the rise of high-impact fires, to name a few. Given these significant and growing challenges, conventional fire management approaches are unlikely to be effective in the future. Innovative and forward-looking approaches are needed. This study explored wildland fire management futures by using methods and diverse perspectives from futures research. To…
Publication Type: Report
Fire and fuels
Year: 2014
Recent studies of historical fire regimes indicate that fires occurring prior to Euro-American settlement were characterized by a high degree of spatial complexity that was driven by heterogeneity in vegetation/fuels and topography and influenced by variability in climate, which mediated the timing, effects, and extents of fires over time. Although there are many important lessons to learn from the past, we may not be able to rely completely on past forest conditions to provide us with blueprints for current and future forest management. Rather than attempting to achieve a particular forest…
Publication Type: Report
Correlations between components of the water balance and burned area reveal insights for predicting forest fire area in the southwest United States
Year: 2014
We related measurements of annual burned area in the southwest United States during 1984–2013 to records of climate variability. Within forests, annual burned area correlated at least as strongly with spring–summer vapour pressure deficit (VPD) as with 14 other drought-related metrics, including more complex metrics that explicitly represent fuel moisture. Particularly strong correlations with VPD arise partly because this term dictates the atmospheric moisture demand. Additionally, VPD responds to moisture supply, which is difficult to measure and model regionally due to complex…
Publication Type: Journal Article
Recent mountain pine beetle outbreaks, wildfire severity, and postfire tree regeneration in the US Northern Rockies
Year: 2014
Widespread tree mortality caused by outbreaks of native bark beetles (Circulionidae: Scolytinae) in recent decades has raised concern among scientists and forest managers about whether beetle outbreaks fuel more ecologically severe forest fires and impair postfire resilience. To investigate this question, we collected extensive field data following multiple fires that burned subalpine forests in 2011 throughout the Northern Rocky Mountains across a spectrum of prefire beetle outbreak severity, primarily from mountain pine beetle (Dendroctonus ponderosae). We found that recent (2001–2010)…
Publication Type: Journal Article