Research Database
Displaying 81 - 100 of 315
A data‐driven analysis and optimization of the impact of prescribed fire programs on wildfire risk in different regions of the USA
Year: 2023
In the current century, wildfires have shown an increasing trend, causing a huge amount of direct and indirect losses in society. Different methods and efforts have been employed to reduce the frequency and intensity of the damages, one of which is implementing prescribed fires. Previous works have established that prescribed fires are effective at reducing the damage caused by wildfires. However, the actual impact of prescribed fire programs is dependent on factors such as where and when prescribed fires are conducted. In this paper, we propose a novel data-driven model studying the impact…
Publication Type: Journal Article
Climate change is narrowing and shifting prescribed fire windows in western United States
Year: 2023
Escalating wildfire activity in the western United States has accelerated adverse societal impacts. Observed increases in wildfire severity and impacts to communities have diverse anthropogenic causes—including the legacy of fire suppression policies, increased development in high-risk zones, and aridification by a warming climate. However, the intentional use of fire as a vegetation management tool, known as “prescribed fire,” can reduce the risk of destructive fires and restore ecosystem resilience. Prescribed fire implementation is subject to multiple constraints, including the number of…
Publication Type: Journal Article
Exploring and Testing Wildfire Risk Decision-Making in the Face of Deep Uncertainty
Year: 2023
We integrated a mechanistic wildfire simulation system with an agent-based landscape change model to investigate the feedbacks among climate change, population growth, development, landowner decision-making, vegetative succession, and wildfire. Our goal was to develop an adaptable simulation platform for anticipating risk-mitigation tradeoffs in a fire-prone wildland–urban interface (WUI) facing conditions outside the bounds of experience. We describe how five social and ecological system (SES) submodels interact over time and space to generate highly variable alternative futures even within…
Publication Type: Journal Article
Rapid fuel recovery after stand-replacing fire in closed-cone pine forests and implications for short-interval severe reburns
Year: 2023
Accelerating disturbance activity under a warming climate increases the potential for multiple disturbances to overlap and produce compound effects that erode ecosystem resilience — the capacity to experience disturbance without transitioning to an alternative state. A key concern is the potential for amplifying or attenuating feedbacks via interactions among successive, linked disturbance events. Following severe wildfires, fuel limitation is a negative feedback that may reduce the likelihood of subsequent fire. However, the duration of, and pre-fire vegetation effects on fuel limitation…
Publication Type: Journal Article
Climate and fire impacts on tree recruitment in mixed conifer forests in Northwestern Mexico and California
Year: 2023
Frequent-fire forests were once heterogeneous at multiple spatial scales, which contributed to their resilience to severe fire. While many studies have characterized historical spatial patterns in frequent-fire forests, fewer studies have investigated their temporal dynamics. We investigated the influences of fire and climate on the timing of conifer recruitment in old-growth Jeffrey pine-mixed conifer forests in the Sierra San Pedro Martir (SSPM) and the eastern slope of Sierra Nevada. Additionally, we evaluated the impacts of fire exclusion and recent climate change on recruitment levels…
Publication Type: Journal Article
Prescribed fire after thinning increased resistance of sub-Mediterranean pine forests to drought events and wildfires
Year: 2023
Vegetation structure affects the vulnerability of a forest to drought events and wildfires. Management decisions, such as thinning intensity and type of understory treatment, influence competition for water resources and amount of fuel available. While heavy thinning effectively reduces tree water stress and intensity of a crown fire, the duration of these benefits may be limited by a fast growth response of the understory. Our aim was to study the effect of forest structure on pine forests vulnerability to extreme drought events and on the potential wildfire behaviour after management, with…
Publication Type: Journal Article
A roadmap for pyrodiversity science
Year: 2023
Background
Contemporary and projected shifts in global fire regimes highlight the importance of understanding how fire affects ecosystem function and biodiversity across taxa and geographies. Pyrodiversity, or heterogeneity in fire history, is often an important driver of biodiversity, though it has been largely overlooked until relatively recently. In this paper, we synthesise previous research to develop a theoretical framework on pyrodiversity–biodiversity relationships and propose future research and conservation management directions.
Theoretical Framework
Pyrodiversity may affect…
Publication Type: Journal Article
Climate influences on future fire severity: a synthesis of climate-fire interactions and impacts on fire regimes, high-severity fire, and forests in the western United States
Year: 2023
Background
Increases in fire activity and changes in fire regimes have been documented in recent decades across the western United States. Climate change is expected to continue to exacerbate impacts to forested ecosystems by increasing the frequency, size, and severity of wildfires across the western United States (US). Warming temperatures and shifting precipitation patterns are altering western landscapes and making them more susceptible to high-severity fire. Increases in large patches of high-severity fire can result in significant impacts to landscape processes and ecosystem function…
Publication Type: Journal Article
Creating Fire-Adapted Communities Through Recovery: Case Studies from the United States and Australia
Year: 2023
Wildfires can be devastating for social and ecological systems, but the recovery period after wildfire presents opportunities to reduce future risk through adaptation. We use a collective case study approach to systematically compare social and ecological recovery following four major fire events in Australia and the United States: the 1998 wildfires in northeastern Florida; the 2003 Cedar fire in southern California; the 2009 Black Saturday bushfires in Victoria, southeastern Australia; and the 2011 Bastrop fires in Texas. Fires spurred similar policy changes, with an emphasis on education,…
Publication Type: Journal Article
Managed Wildfire: A Research Synthesis and Overview
Year: 2023
All wildfires in the United States are managed, but the strategies used to manage them vary by region and season. “Managed wildfire” is a response strategy to naturally ignited wildfires; it does not prioritize full suppression and allows the fire to fulfill its natural role on the landscape, meeting objectives such as firefighter safety, resource benefit, and community protection. This wildfire management strategy can be effective for reducing tree densities, landscape homogeneity, fuel load continuity, and future fire behavior, while also working to reintroduce fire to fire-prone ecosystems…
Publication Type: Report
Drivers of California’s changing wildfires: a state-of-the-knowledge synthesis
Year: 2023
Over the past four decades, annual area burned has increased significantly in California and across the western USA. This trend reflects a confluence of intersecting factors that affect wildfire regimes. It is correlated with increasing temperatures and atmospheric vapour pressure deficit. Anthropogenic climate change is the driver behind much of this change, in addition to influencing other climate-related factors, such as compression of the winter wet season. These climatic trends and associated increases in fire activity are projected to continue into the future. Additionally, factors…
Publication Type: Journal Article
Homeowner firewise behaviors in fire-prone central Oregon: An exploration of the attitudinal, situational, and cultural worldviews impacting pre-fire mitigation actions Author links open overlay panel
Year: 2023
Highlights • People with egalitarian cultural traits are more likely to engage in fire mitigation behaviors. • Concern, experience, and proximity all have a positive relationship to engagement in fire mitigation behaviors. • Fire-resistant building materials and landscaping requirements are effective policy tools for homeowner mitigation actions. • Younger homeowners and women are more likely to engage in fire mitigation actions. Abstract As a result of climate change and past management practices, wildfires are becoming larger and occurring more frequently than ever before in the Western U.S…
Publication Type: Journal Article
Building water resilience in the face of cascading wildfire risks
Year: 2023
Severe wildfire is altering the natural and the built environment and posing risks to environmental and societal health and well-being, including cascading impacts to water systems and built water infrastructure. Research on wildfire-resilient water systems is growing but not keeping pace with the scale and severity of wildfire impacts, despite their intensifying threat. In this study, we evaluate the state of knowledge regarding wildfire-related hazards to water systems. We propose a holistic framework to assess interactions and feedback loops between water quality, quantity, and…
Publication Type: Journal Article
Metrics and Considerations for Evaluating How Forest Treatments Alter Wildfire Behavior and Effects
Year: 2023
The influence of forest treatments on wildfire effects is challenging to interpret. This is, in part, because the impact forest treatments have on wildfire can be slight and variable across many factors. Effectiveness of a treatment also depends on the metric considered. We present and define human–fire interaction, fire behavior, and ecological metrics of forest treatment effects on wildfire and discuss important considerations and recommendations for evaluating treatments. We demonstrate these concepts using a case study from the Cameron Peak Fire in Colorado, USA. Pre-fire forest…
Publication Type: Journal Article
Using PODs to integrate fire and fuels planning
Year: 2023
BackgroundPotential Wildfire Operational Delineations (PODs) were developed as a pre-season planning tool to promote safe and effective fire response. Past research on PODs has identified uses in an incident management context. There has been little research on how PODs are being utilised in non-incident management contexts to align forest and wildfire planning objectives.AimsWe sought to understand how actors are adopting and adapting the PODs framework to inform non-incident management, and to identify facilitators, barriers and recommendations.…
Publication Type: Journal Article
Ability of seedlings to survive heat and drought portends future demographic challenges for five southwestern US conifers
Year: 2023
Climate change and disturbance are altering forests and the rates and locations of tree regeneration. In semi-arid forests of the southwestern USA, limitations imposed by hot and dry conditions are likely to influence seedling survival. We examined how the survival of 1-year seedlings of five southwestern US conifer species whose southwestern distributions range from warmer and drier woodlands and forests (Pinus edulis Engelm., Pinus ponderosa Douglas ex C. Lawson) to cooler and wetter subalpine forests (Pseudotsuga menziesii (Mirb.) Franco, Abies concolor…
Publication Type: Journal Article
Mechanical thinning restores ecological functions in a seasonally dry ponderosa pine forest in the inland Pacific Northwest, USA
Year: 2023
An increasingly important goal of federal land managers in seasonally dry forests of the western US is restoring forest resilience. In this study, we quantified the degree to which a thinning treatment in a dry forest of eastern Oregon restored aspects of forest resilience by focusing on key functional attributes of our study system. First, we measured several physiological responses of overstory trees that are associated with resilience, including radial growth, resin production, abundance of non-structural carbohydrates (NSC), and leaf area. Second, we investigated understory vegetation…
Publication Type: Journal Article
How Does Fire Suppression Alter the Wildfire Regime? A Systematic Review
Year: 2023
Fire suppression has become a fundamental approach for shaping contemporary wildfire regimes. However, a growing body of research suggests that aggressive fire suppression can increase high-intensity wildfires, creating the wildfire paradox. Whether the strategy always triggers the paradox remains a topic of ongoing debate. The role of fire suppression in altering wildfire regimes in diverse socio-ecological systems and associated research designs demands a deeper understanding. To reconcile these controversies and synthesize the existing knowledge, a systematic review has been conducted to…
Publication Type: Journal Article
Homeowner firewise behaviors in fire-prone central Oregon: An exploration of the attitudinal, situational, and cultural worldviews impacting pre-fire mitigation actions
Year: 2023
As a result of climate change and past management practices, wildfires are becoming larger and occurring more frequently than ever before in the Western U.S. In order to mitigate the effects of this growing threat, fire management agencies such as the U.S. Forest Service have encouraged residents in at-risk communities to protect their homes, property, and communities by adopting Firewise recommendations. Using a survey of wildland-urban interface (WUI) homeowners in fire-prone Deschutes County, Oregon, this study examines homeowners' participation in Firewise activities. While the majority…
Publication Type: Journal Article
Exploring the impact of airtanker drops on in-stand temperature and relative humidity
Year: 2023
Background. There has been little quantification of the extent and duration of micro- meteorological changes within a forest after airtanker drops of water-based suppressant. It has been speculated that a period of prolonged relative humidity – referred to as a ‘relative humidity (RH) bubble’ – temporarily exists in the canopy understorey post-drop. Aims. We quantify the RH bubble from the drops of five airtankers commonly used by wildland fire management organisations in Canada. Methods. We measured airtankers dropping water, foam concentrates, and gel enhancers in a mature jack pine stand.…
Publication Type: Journal Article