Research Database
Displaying 81 - 94 of 94
Drivers of Wildfire Suppression Costs: Literature Review and Annotated Bibliography
Year: 2015
Over the past century, wildland fire management has been core to the mission of federal land management agencies. In recent decades, however, federal spending on wildfire suppression has increased dramatically; suppression spending that on average accounted for less than 20 percent of the USFS’s discretionary funds prior to 2000 had grown to 43 percent of discretionary funds by 2008 (USDA 2009), and 51 percent in 2014 (USDA 2014). Rising suppression costs have created budgetary shortfalls and conflict as money “borrowed” from other budgets often cannot be paid back in full, and resources for…
Publication Type: Report
Topography, fuels, and fire exclusion drive fire severity of the Rim Fire in an old-growth mixed-conifer forest, Yosemite National Park, USA
Year: 2015
The number of large, high-severity fires has increased in the western United States over the past 30 years due to climate change and increasing tree density from fire suppression. Fuel quantity, topography, and weather during a burn control fire severity, and the relative contributions of these controls in mixed-severity fires in mountainous terrain are poorly understood. In 2013, the Rim Fire burned a previously studied 2125 ha area of mixed-conifer forest in Yosemite National Park. Data from 84 plots sampled in 2002 revealed increases in tree density, basal area, and fuel buildup since 1899…
Publication Type: Journal Article
Operational wildfire suppression modelling: a review evaluating development, state of the art and future directions
Year: 2015
Wildfires are an inherent part of the landscape in many parts of the world; however, they often impose substantial economic burdens on human populations where they occur, both in terms of impacts and of management costs. As wildfires burn towards human assets, a universal response has been to deploy fire suppression resources (crews, vehicles and aircraft) to extinguish them, and limit their spread or impacts. The determination of the appropriate levels of investment, resource allocation and suppression tactics is a challenge for managers. As suppression expenses account for a substantial…
Publication Type: Journal Article
Post-fire response of riparian vegetation in a heavily browsed environment
Year: 2015
Severe wildfires infrequently occur in large heterogeneous riparian valleys. Riparian areas may affect fire behavior and the pattern of burning due to saturated soils and patchy fuels that may have high moisture content in live and dead stems. We examined the effects of a severe fire on the dominant riparian vegetation: thin-leaf alder, river birch and willow, in a broad riparian valley in Rocky Mountain National Park, CO, USA. We mapped the canopy stem mortality and basal resprouting of 4507 first year post fire and 643 second year post fire individuals that had been the dominant woody…
Publication Type: Journal Article
Effects of burn status and conditioning on colonization of wood by stream macroinvertebrates
Year: 2014
The combination of changing climate and anthropogenic activities is increasing the probability of wildfire around the world. When fires occur in riparian zones, associated tree mortality can add wood directly to streams or wood may fall to the forest floor and remain there for some time before being transported into stream channels. Wood provides critical structure for aquatic macroinvertebrates, so our objectives were to assess the effects of wood burn status, conditioning, and their interaction on macroinvertebrate community composition, taxon and functional diversity, and trait affinities…
Publication Type: Journal Article
Wildland firefighter safety zones: a review of past science and summary of future needs
Year: 2014
Current wildland firefighter safety zone guidelines are based on studies that assume flat terrain, radiant heating, finite flame width, constant flame temperature and high flame emissivity. Firefighter entrapments and injuries occur across a broad range of vegetation, terrain and atmospheric conditions generally when they are within two flame heights of the fire. Injury is not confined to radiant heating or flat terrain; consequently, convective heating should be considered as a potential heating mode. Current understanding of energy transport in wildland fires is briefly summarised, followed…
Publication Type: Journal Article
Wildland firefighter entrapment avoidance: modelling evacuation triggers
Year: 2013
Wildland firefighters are often called on to make tactical decisions under stressful conditions in order to suppress a fire. These decisions can be hindered by human factors such as insufficient knowledge of surroundings and conditions, lack of experience, overextension of resources or loss of situational awareness. One potential tool for assisting fire managers in situations where human factors can hinder decision-making is the Wildland–Urban Interface Evacuation (WUIVAC) model, which models fire minimum travel times to create geographic trigger buffers for evacuation recommendations.…
Publication Type: Journal Article
Wildfire severity mediates fluxes of plant material and terrestrial invertebrates to mountain streams
Year: 2012
Wildfire effects upon riparian plant community structure, composition, and distribution may strongly influence the dynamic relationships between riparian vegetation and stream ecosystems. However, few studies have examined the influence of fire on these processes. To that end, we compared the quantity and composition of allochthonous inputs of plant material and terrestrial invertebrates among stream tributaries characterized by various degrees of burn severity 5 years post-fire in the Frank Church Wilderness of central Idaho, USA. The magnitude of inputs of coniferous leaf litter to unburned…
Publication Type: Journal Article
Synthesis of Knowledge of Extreme Fire Behavior: Volume I for Fire Managers
Year: 2011
The National Wildfire Coordinating Group definition of extreme fire behavior (EFB) indicates a level of fire behavior characteristics that ordinarily precludes methods of direct control action. One or more of the following is usually involved: high rate of spread, prolific crowning/spotting, presence of fire whirls, and strong convection column. Predictability is difficult because such fires often exercise some degree of influence on their environment and behave erratically, sometimes dangerously. Alternate terms include “blow up” and “fire storm.” Fire managers examining fires over the last…
Publication Type: Report
The fire pulse: wildfire stimulates flux of aquatic prey to terrestrial habitats driving increase in riparian consumers
Year: 2010
We investigated the midterm effects of wildfire (in this case, five years after the fire) of varying severity on periphyton, benthic invertebrates, emerging adult aquatic insects, spiders, and bats by comparing unburned sites with those exposed to low severity (riparian vegetation burned but canopy intact) and high severity (canopy completely removed) wildfire. We observed no difference in periphyton chlorophyll a or ash-free dry mass among different burn categories but did observe significantly greater biomass of benthic invertebrates in both high severity burned and unburned reaches versus…
Publication Type: Journal Article
Prescribed fires as ecological surrogates for wildfires: A stream and riparian perspective
Year: 2010
Forest managers use prescribed fire to reduce wildfire risk and to provide resource benefits, yet little information is available on whether prescribed fires can function as ecological surrogates for wildfire in fire-prone landscapes. Information on impacts and benefits of this management tool on stream and riparian ecosystems is particularly lacking. We used a beyond-BACI (Before, After, Control, Impact) design to investigate the effects of a prescribed fire on a stream ecosystem and compared these findings to similar data collected after wildfire. For 3 years after prescribed fire treatment…
Publication Type: Journal Article
Has Fire Suppression Increased the Amount of Carbon Stored in Western US Forests?
Year: 2008
Active 20th century fire suppression in western US forests, and a resulting increase in stem density, is thought to account for a significant fraction of the NorthAmerican carbon sink. We compared California forest inventories from the 1930s with inventories from the 1990s to quantify changes in aboveground biomass. Stem density in mid-montane conifer forests increased by 34%, while live aboveground carbon stocks decreased by 26%. Increased stem density reflected an increase in the number of small trees and a net loss of large trees. Large trees contain a disproportionate amount of carbon,…
Publication Type: Journal Article
Smoke on the hill: A comparative study of wildfire and two communities
Year: 2003
Wildfire represents a serious challenge to communities in the rural West. After decades of fire suppression, land managers now perceive a greater role for wildfire in the ecosystem. In the meantime, migration patterns from urban to rural settings have increased the number of people living in forested areas throughout the West, therefore; wildfires are a threat to more homes than ever in the region. This study focuses on two communities’ response to wildfires during the intense fire season of 1994. Through qualitative research methods, the study analyzes these diverse responses in the context…
Publication Type: Journal Article