Research Database
Displaying 21 - 40 of 198
Long-term influence of prescribed burning on subsequent wildfire in an old-growth coast redwood forest
Year: 2025
Background: Prescribed burning is an effective tool for reducing fuels in many forest types, yet there have been few opportunities to study forest resilience to wildfire in areas previously treated. In 2020, a large-scale high-intensity wildfire burned through an old-growth coast redwood (Sequoia sempervirens) forest with a mixed land management history, providing a rare opportunity to compare early post-wildfire data between areas with and without previous application of prescribed burning. The purpose of this study was to analyze the differences between these two treatments in…
Publication Type: Journal Article
Short-term impacts of operational fuel treatments on modelled fire behaviour and effects in seasonally dry forests of British Columbia, Canada
Year: 2025
Background: In response to increasing risk of extreme wildfire across western North America, forest managers are proactively implementing fuel treatments.Aims: We assessed the efficacy of alternative combinations of thinning, pruning and residue fuel management to mitigate potential fire behaviour and effects in seasonally dry forests of interior British Columbia, Canada.Methods: Across five community forests, we measured stand attributes before and after fuel treatments in 2021 and 2022, then modelled fire behaviour and effects using the…
Publication Type: Journal Article
Experimental study on the evolution of canyon fire spread behavior under different terrains and the critical conditions for eruptive fire
Year: 2025
BackgroundThe spread of canyon fire often involves sudden acceleration, which is related to eruptive fire.AimsThe purpose of the study is to explore the pattern of fire line evolution and rate of spread (ROS) with topographic conditions in canyon fire, and to clarify the critical conditions for and mechanism of eruptive fire.MethodsA systematic experimental study on canyon fire was conducted by igniting dead pine needles with a point ignition.Key resultsFour different types of fire line contours were identified under…
Publication Type: Journal Article
Global firestorm: Igniting insights on environmental and socio-economic impacts for future research
Year: 2025
Forests are vital life-preserving assets, essential for biodiversity, human health, climate change mitigation, and economic stability. Yet, they are increasingly threatened by forest fires, which undermine these benefits. In the first half of 2025, forest fires in the United States burned over 810,000 acres, Canada lost 7.3 million hectares, while the 2020 Australian mega-fires, which caused an estimated US $20 billion in economic losses, illustrate the scale and urgency of the problem. Despite such impacts, research integrating the diverse dimensions of forest fires, including suppression…
Publication Type: Journal Article
Patterns, drivers, and implications of postfire delayed tree mortality in temperate conifer forests of the western United States
Year: 2024
Conifer forest resilience may be threatened by increasing wildfire activity and compound disturbances in western North America. Fire refugia enhance forest resilience, yet may decline over time due to delayed mortality—a process that remains poorly understood at landscape and regional scales. To address this uncertainty, we used high-resolution satellite imagery (5-m pixel) to map and quantify delayed mortality of conifer tree cover between 1 and 5 years postfire, across 30 large wildfires that burned within three montane ecoregions in the western United States. We used statistical models to…
Publication Type: Journal Article
Long-term sensitivity of ponderosa pine axial resin ducts to harvesting and prescribed burning
Year: 2024
Forest restoration treatments primarily aimed at reducing fuel load and preventing high-severity wildfires can also influence resilience to other disturbances. Many pine forests in temperate regions are subject to tree-killing bark beetle outbreaks (e.g., Dendroctonus, Ips), whose frequency and intensity are expected to increase with future climatic changes. Restoration treatments have the potential to increase resistance to bark beetle attacks, yet the underlying mechanisms of this response are still unclear. While the effect of forest restoration treatments on tree growth…
Publication Type: Journal Article
Fire intensity effects on serotinous seed survival
Year: 2024
BackgroundIn fire-prone environments, some species store their seeds in canopy cones (serotiny), which provides seeds protection from the passage of fire before stimulating seed release. However, the capacity of serotinous cones to protect seeds under high intensity fire is uncertain. Beyond simply “high” versus “low” fire intensity or severity, we must understand the influence of the specific characteristics of fire intensity—heat flux, exposure duration, and their dynamics—on serotinous seed survival. In this study, we tested serotinous seed survival under transient levels of…
Publication Type: Journal Article
Optimising disaster response: opportunities and challenges with Uncrewed Aircraft System (UAS) technology in response to the 2020 Labour Day wildfires in Oregon, USA
Year: 2024
BackgroundThe expanding use of Uncrewed Aircraft System (UAS) technology in disaster response shows its immense potential to enhance emergency management. However, there is limited documentation on the challenges and data management procedures related to UAS operation.AimsThis manuscript documents and analyses the operational, technical, political, and social challenges encountered during the deployment of UAS, providing insights into the complexities of using these technologies in disaster situations.MethodsThis manuscript documents and…
Publication Type: Journal Article
Leveraging the next generation of spaceborne Earth observations for fuel monitoring and wildland fire management
Year: 2024
Managing fuels is a key strategy for mitigating the negative impacts of wildfires on people and the environment. The use of satellite-based Earth observation data has become an important tool for managers to optimize fuel treatment planning at regional scales. Fortunately, several new sensors have been launched in the last few years, providing novel opportunities to enhance fuel characterization. Herein, we summarize the potential improvements in fuel characterization at large scale (i.e., hundreds to thousands of km2) with high spatial and spectral resolution arising from the use of new…
Publication Type: Journal Article
How are long-term stand structure, fuel profiles, and potential fire behavior affected by fuel treatment type and intensity in Interior Pacific Northwest forests?
Year: 2024
Fuel treatments are commonly applied to increase resilience to wildfire in dry and historically frequent-fire forests of western North America. The long-term effects of fuel treatments on forest structure, fuel profiles (amount and configuration of fuels), and potential wildfire behavior are not well known relative to short-term effects. Additionally, long-term treatment effects on the development of stand structure and fuel profiles have rarely been compared to the long-term effects of pre-treatment conditions, treatment intensity, and site productivity. In this study, we addressed these…
Publication Type: Journal Article
Thinning and Managed Burning Enhance Forest Resilience in Northeastern California
Year: 2024
Understanding and quantifying the resilience of forests to disturbances are increasingly important for forest management. Historical fire suppression, logging, and other land uses have increased densities of shade tolerant trees and fuel buildup in the western United States, which has reduced the resilience of these forests to natural disturbances. One way to mitigate this problem is to use fuel treatments such as stand thinning and prescribed burning. In this study, we investigated changes in forest structure in the Lassen and Plumas National Forests of northern California following a large…
Publication Type: Journal Article
Drivers and Impacts of the Record-Breaking 2023 Wildfire Season in Canada
Year: 2024
The 2023 wildfire season in Canada was unprecedented in its scale and intensity, spanning from mid-April to late October and across much of the forested regions of Canada. Here, we summarize the main causes and impacts of this exceptional season. The record-breaking total area burned (~15 Mha)can be attributed to several environmental factors that converged early in the season: early snowmelt, multi annual drought conditions in western Canada, and the rapid transition to drought in eastern Canada. Anthropogenic climate change enabled sustained extreme fire weather conditions, as the meanMay–…
Publication Type: Journal Article
Review of fuel treatment effects on fuels, fire behavior and ecological resilience in sagebrush (Artemisia spp.) ecosystems in the Western U.S.
Year: 2024
BackgroundSagebrush ecosystems are experiencing increases in wildfire extent and severity. Most research on vegetation treatments that reduce fuels and fire risk has been short term (2–3 years) and focused on ecological responses. We review causes of altered fire regimes and summarize literature on the longer-term effects of treatments that modify (1) shrub fuels, (2) pinyon and juniper canopy fuels, and (3) fine herbaceous fuels. We describe treatment effects on fuels, fire behavior, ecological resilience, and resistance to invasive annual grasses.ResultsOur review revealed tradeoffs in…
Publication Type: Journal Article
Stand diversity increases pine resistance and resilience to compound disturbance
Year: 2024
BackgroundDrought, fire, and insects are increasing mortality of pine species throughout the northern temperate zone as climate change progresses. Tree survival may be enhanced by forest diversity, with growth rates often higher in mixed stands, but whether tree defenses are likewise aided remains in question. We tested how forest diversity-productivity patterns relate to growth and defense over three centuries of climate change, competition, wildfire, and bark beetle attack. We used detailed census data from a fully mapped 25.6-ha forest dynamics plot in California, USA to…
Publication Type: Journal Article
Hydrometeorology-wildfire relationship analysis based on a wildfire bivariate probabilistic framework in different ecoregions of the continental United States
Year: 2024
Wildfires are a natural part of the ecosystem in the U.S.. It is vital to classify wildfires using a comprehensive approach that simultaneously considers wildfire activity (the number of wildfires) and burned area. On this basis, the influence of hydrometeorological variables on wildfires can be further analyzed. Therefore, this study first classified wildfire types using a wildfire bivariate probability framework. Then, by considering six hydrometeorological variables, the dominant hydrometeorological variables for different wildfire types in 17 ecoregions of the United States were…
Publication Type: Journal Article
The impacts of rising vapour pressure deficit in natural and managed ecosystems
Year: 2024
An exponential rise in the atmospheric vapour pressure deficit (VPD) is among the most consequential impacts of climate change in terrestrial ecosystems. Rising VPD has negative and cascading effects on nearly all aspects of plant function including photosynthesis, water status, growth and survival. These responses are exacerbated by land–atmosphere interactions that couple VPD to soil water and govern the evolution of drought, affecting a range of ecosystem services including carbon uptake, biodiversity, the provisioning of water resources and crop yields. However, despite the…
Publication Type: Journal Article
Estimating masticated and cone fuel loads using the Photoload method
Year: 2024
BackgroundRecognizing the complexity and varied nature of forest fuelbeds is crucial in understanding fire behavior and effects on the landscape. While current modeling efforts often consider fine and coarse woody debris surface fuel loads, those options do not always provide the most complete description of the fuelbeds. Both masticated fuels and cones can be a significant part of the fuelbed, with the potential to influence fire behavior and effects, but they are not currently captured in planar intersect methods or Photoload fuel sampling methodology. Cones are prevalent in most forested…
Publication Type: Journal Article
Wildfire management decisions outweigh mechanical treatment as the keystone to forest landscape adaptation
Year: 2024
BackgroundModern land management faces unprecedented uncertainty regarding future climates, novel disturbance regimes, and unanticipated ecological feedbacks. Mitigating this uncertainty requires a cohesive landscape management strategy that utilizes multiple methods to optimize benefits while hedging risks amidst uncertain futures. We used a process-based landscape simulation model (LANDIS-II) to forecast forest management, growth, climate effects, and future wildfire dynamics, and we distilled results using a decision support tool allowing us to examine tradeoffs between alternative…
Publication Type: Journal Article
State of Wildfires 2023–2024
Year: 2024
Climate change contributes to the increased frequency and intensity of wildfires globally, with significant impacts on society and the environment. However, our understanding of the global distribution of extreme fires remains skewed, primarily influenced by media coverage and regionalised research efforts. This inaugural State of Wildfires report systematically analyses fire activity worldwide, identifying extreme events from the March 2023–February 2024 fire season. We assess the causes, predictability, and attribution of these events to climate change and land use and forecast future risks…
Publication Type: Journal Article
Long-term frequent fire and cattle grazing alter dry forest understory vegetation
Year: 2024
Understanding fire and large herbivore interactions in interior western forests is critical, owing to the extensive and widespread co-occurrence of these two disturbance types and multiple present and future implications for forest resilience, conservation and restoration. However, manipulative studies focused on interactions and outcomes associated with these two disturbances are rare in forested rangelands. We investigated understory vegetation response to 5-year spring and fall prescribed fire and domestic cattle grazing exclusion in ponderosa pine stands and reported long-term responses,…
Publication Type: Journal Article