Research Database
Displaying 61 - 80 of 257
External drivers of changes in wildland firefighter safety policies and practices
Year: 2024
Background: Firefighter safety is a top priority in wildland fire response and management. Existing explanations emphasise how land management agency initiatives to change organisational culture, usually inspired by fatality incidents, contribute to changes both in formal safety policies and informal safety practices. Aims: This paper identifies external factors that lead to changes in wildland firefighter safety policies and practices. Methods: This paper uses qualitative data from a long-term ethnographic research project. Data include…
Publication Type: Journal Article
Abiotic Factors Modify Ponderosa Pine Regeneration Outcomes After High-Severity Fire
Year: 2024
Large high-severity burn patches are increasingly common in southwestern US dry conifer forests. Seed-obligate conifers often fail to quickly regenerate large patches because their seeds rarely travel the distances required to reach core patch area. Abiotic factors may further alter the distance seeds can travel to regenerate a patch, which would change expected post-fire regeneration patterns. We used the presence and density of ponderosa pine regeneration as a proxy for seed dispersal to quantify the effect of abiotic factors on seed dispersal into high-severity patches. We established 45…
Publication Type: Journal Article
Improving social resilience to forest fire from community perspective
Year: 2024
Recently, terms like social and community resilience have provided new ideas in reducing disaster risks especially in forest fire. However, a comprehensive and in-depth review of community social resilience concerning forest fires is lacking. There is little research investigate whether certain social or community resilience factors can initiate forest fires or whether forest fire prevention positively be influenced by them. To fill this gap, this paper aims to identify and discuss the factors influencing the occurrence of forest fires in the scope of community social resilience. It also…
Publication Type: Journal Article
Spatial and temporal analysis of vulnerability disparity of minorities to wildfires in California
Year: 2024
Wildfires typically have devastating impacts on communities, both in urban and rural areas, resulting in property loss, psychological distress, physical injuries, and loss of life. A notable gap in the literature is the spatial and temporal disproportionate impact of wildfires on underrepresented communities. This lack of attention is concerning, as these underrepresented populations are likely to be more vulnerable to the devastating consequences of wildfire disasters, exacerbating pre-existing social, economic, and environmental disparities. This study aims to address this gap by conducting…
Publication Type: Journal Article
Contemporary fires are less frequent but more severe in dry conifer forests of the southwestern United States
Year: 2024
Wildfires in the southwestern United States are increasingly frequent and severe, but whether these trends exceed historical norms remains contested. Here we combine dendroecological records, satellite-derived burn severity, and field measured tree mortality to compare historical (1700-1880) and contemporary (1985-2020) fire regimes at tree-ring fire-scar sites in Arizona and New Mexico. We found that contemporary fire frequency, including recent, record fire years, is still <20% of historical levels. Since 1985, the fire return interval averages 58.8 years, compared to 11.4 years before…
Publication Type: Journal Article
Exploring spatial heterogeneity in synergistic effects of compound climate hazards: Extreme heat and wildfire smoke on cardiorespiratory hospitalizations in California
Year: 2024
Extreme heat and wildfire smoke events are increasingly co-occurring in the context of climate change, especially in California. Extreme heat and wildfire smoke may have synergistic effects on population health that vary over space. We leveraged high-resolution satellite and monitoring data to quantify spatially varying compound exposures to extreme heat and wildfire smoke in California (2006–2019) at ZIP Code Tabulation Area (ZCTA) level. We found synergistic effects between extreme heat and wildfire smoke on daily cardiorespiratory hospitalizations at the state level. We also found spatial…
Publication Type: Journal Article
Estimating the influence of field inventory sampling intensity on forest landscape model performance for determining high-severity wildfire risk
Year: 2024
Historically, fire has been essential in Southwestern US forests. However, a century of fire-exclusion and changing climate created forests which are more susceptible to uncharacteristically severe wildfires. Forest managers use a combination of thinning and prescribed burning to reduce forest density to help mitigate the risk of high-severity fires. These treatments are laborious and expensive, therefore optimizing their impact is crucial. Landscape simulation models can be useful in identifying high risk areas and assessing treatment effects, but uncertainties in these models can limit…
Publication Type: Journal Article
Trees have similar growth responses to first-entry fires and reburns following long-term fire exclusion
Year: 2024
Managing fire ignitions for resource benefit decreases fuel loads and reduces the risk of high-severity fire in fire-suppressed dry conifer forests. However, the reintroduction of low-severity wildfire can injure trees, which may decrease their growth after fire. Post-fire growth responses could change from first-entry fires to reburns, as first-entry fires reduce fuel loads and the vulnerability among trees to fire effects, which may result in trees sustaining less damage during reburns. To determine whether trees had growth responses that varied from first-entry fires to reburns, we cored…
Publication Type: Journal Article
Assessing Conservation Readiness: The Where, Who, and How of Strategic Conservation in the Sagebrush Biome
Year: 2024
The sagebrush biome is rapidly deteriorating largely due to the ecosystem threats of conifer expansion, more frequent and larger wildfires, and proliferation of invasive annual grasses. Reversing the impacts of these threats is a formidable challenge. The Sagebrush Conservation Design (SCD) emphasized that limited conservation resources should first be used to maintain Core Sagebrush Areas (CSA), and then to grow such areas where possible. The SCD heightens the ecological importance of maintaining and strategically growing CSAs. However, the fact that these areas have been identified does not…
Publication Type: Journal Article
Ladder fuels rather than canopy volumes consistently predict wildfire severity even in extreme topographic-weather conditions
Year: 2024
Drivers of forest wildfire severity include fuels, topography and weather. However, because only fuels can be actively managed, quantifying their effects on severity has become an urgent research priority. Here we employed GEDI spaceborne lidar to consistently assess how pre-fire forest fuel structure affected wildfire severity across 42 California wildfires between 2019–2021. Using a spatial-hierarchical modeling framework, we found a positive concave-down relationship between GEDI-derived fuel structure and wildfire severity, marked by increasing severity with greater fuel loads until a…
Publication Type: Journal Article
Climate limits vegetation green-up more than slope, soil erodibility, and immediate precipitation following high-severity wildfire
Year: 2024
BackgroundIn the southwestern United States, post-fire vegetation recovery is increasingly variable in forest burned at high severity. Many factors, including temperature, drought, and erosion, can reduce post-fire vegetation recovery rates. Here, we examined how year-of-fire precipitation variability, topography, and soils influenced post-fire vegetation recovery in the southwestern United States as measured by greenness to determine whether erosion-related factors would have persistent effects in the longer post-fire period. We modeled relationships between post-fire vegetation and these…
Publication Type: Journal Article
How bureaucracies interact with Indigenous Fire Stewardship (IFS): a conceptual framework
Year: 2024
BackgroundIndigenous Fire Stewardship (IFS) is contested within settler-colonial contexts, where its development is shaped by complex and dynamic socio-cultural, legal, and political factors. This manuscript draws from the policy sciences to sketch out a “zone of interaction” between IFS and the state’s wildfire policy system. Drawing from the strategies of bureaucracies, our goal is to illustrate the patterns in this “zone of interaction,” and to identify the implications for IFS, as well as for Indigenous Peoples and landscapes.ResultsDrawing insights from the Australian and Canadian…
Publication Type: Journal Article
The influence of wildfire risk reduction programs and practices on recreation visitation
Year: 2024
Background: The increasing extent and severity of uncharacteristic wildfire has prompted numerous policies and programs promoting landscape-scale fuels reduction. Aims: We used novel data sources to measure how recreation was influenced by fuels reduction efforts under the US Forest Service Collaborative Forest Landscape Restoration (CFLR) Program. Methods: We used posts to four social media platforms to estimate the number of social media user-days within CFLR landscapes and asked: (1) did visitation within CFLR Program landscapes between…
Publication Type: Journal Article
Stream chemical response is mediated by hydrologic connectivity and fire severity in a Pacific Northwest forest
Year: 2024
Large-scale wildfires are becoming increasingly common in the wet forests of the Pacific Northwest (USA), with predicted increases in fire prevalence under future climate scenarios. Wildfires can alter streamflow response to precipitation and mobilize water quality constituents, which pose a risk to aquatic ecosystems and downstream drinking water treatment. Research often focuses on the impacts of high-severity wildfires, with stream biogeochemical responses to low- and mixed-severity fires often understudied, particularly during seasonal shifts in hydrologic connectivity between hillslopes…
Publication Type: Journal Article
Effects of nurse shrubs and biochar on planted conifer seedling survival and growth in a high-severity burn patch in New Mexico, USA
Year: 2023
The synergistic effects of widespread high-severity wildfire and anthropogenic climate change are driving large-scale vegetation conversion. In the southwestern United States, areas that were once dominated by conifer forests are now shrub- or grasslands after high-severity wildfire, an ecosystem conversion that could be permanent without human intervention. Yet, the reforestation of these landscapes is rarely successful, with a mean planted seedling survival of just 25 %. Given these low rates, we carried out a planting experiment to quantify the impacts of biochar as a soil amendment and…
Publication Type: Journal Article
Wildfire risk, salience, and housing development in the wildland–urban interface
Year: 2023
As wildfires increase in both severity and frequency, understanding the role of risk saliency on human behaviors in the face of fire risks becomes paramount. While research has shown that homebuyers capitalize wildfire risk following a fire, studies of the role that risk saliency plays on residential development is limited. This paper aims to fill this gap by studying the link between wildfire risk saliency and the rate of residential development in wildfire-prone areas, by treating recent wildfires as conditionally exogenous shocks to saliency. Using geospatial data on residential…
Publication Type: Journal Article
The outsized role of California’s largest wildfires in changing forest burn patterns and coarsening ecosystem scale
Year: 2023
Highlights • We evaluated trends for 1,809 fires that burned 1985–2020 across California forests. • Top 1% of fires by size burned 47% of total area burned across the study period. • Top 1% (18 fires) produced 58% of high and 42% of low-moderate severity area. • Top 1% created novel landscape patterns of large burn severity patches. • These large fires create new opportunities for managing forest resilience. Although recent large wildfires in California forests are well publicized in media and scientific literature, their cumulative effects on forest structure and implications for forest…
Publication Type: Journal Article
Too hot, too cold, or just right: Can wildfire restore dry forests of the interior Pacific Northwest?
Year: 2023
As contemporary wildfire activity intensifies across the western United States, there is increasing recognition that a variety of forest management activities are necessary to restore ecosystem function and reduce wildfire hazard in dry forests. However, the pace and scale of current, active forest management is insufficient to address restoration needs. Managed wildfire and landscape-scale prescribed burns hold potential to achieve broad-scale goals but may not achieve desired outcomes where fire severity is too high or too low. To explore the potential for fire alone to restore dry forests…
Publication Type: Journal Article
Predicting snag fall in an old-growth forest after fire
Year: 2023
Snags, standing dead trees, are becoming more abundant in forests as tree mortality rates continue to increase due to fire, drought, and bark beetles. Snags provide habitat for birds and small mammals, and when they fall to the ground, the resulting logs provide additional wildlife habitat and affect nutrient cycling, fuel loads, and fire behavior. Predicting how long snags will remain standing after fire is essential for managing habitat, understanding chemical cycling in forests, and modeling forest succession and fuels. Few studies, however, have quantified how fire changes snag fall…
Publication Type: Journal Article
Spatial interactions among short-interval fires reshape forest landscapes
Year: 2023
Aim Ecological disturbances are increasing as climate warms, and how multiple disturbances interact spatially to drive landscape change is poorly understood. We quantified burn severity across fire regimes in reburned forest landscapes to ask how spatial patterns of high-severity fire differ between sequential overlapping fires and how landscape heterogeneity is shaped by cumulative disturbance patterns. We also characterized the amount and configuration of an emerging phenomenon: areas burned as high-severity fire twice in successive fires. Location Northwest USA. Time period 1984–2020.…
Publication Type: Journal Article