Research Database
Displaying 281 - 300 of 309
The Long-Term Effects of Wildfire and Post-Fire Vegetation on Sierra Nevada Forest Soils
Year: 2012
This paper compares carbon (C) and nutrient contents in soils (Alfisols derived from andesite), forest floor and vegetation in a former fire (1960) and an adjacent forest in the Sagehen Watershed in the Sierra Nevada Mountains of California. Soils from the former fire (now occupied predominantly by Ceanothus velutinus, a nitrogen-fixing shrub) had significantly lower contents of extractable SO42− and P (both Bray and bicarbonate) but significantly greater contents of exchangeable Ca2+ than the adjacent forested site (dominated by Pinus jeffreyii). N data suggested that N fixation had occurred…
Publication Type: Journal Article
The Effects of Forest Fuel-Reduction Treatments in the United States
Year: 2012
The current conditions of many seasonally dry forests in the western and southern United States, especially those that once experienced low- to moderate-intensity fire regimes, leave them uncharacteristically susceptible to high-severity wildfire. Both prescribed fire and its mechanical surrogates are generally successful in meeting short-term fuel-reduction objectives such that treated stands are more resilient to high-intensity wildfire. Most available evidence suggests that these objectives are typically accomplished with few unintended consequences, since most ecosystem components (…
Publication Type: Journal Article
Impact of postfire logging on soil bacterial and fungal communities on biogeochemistry in a mixed-conifer forest in central Oregon
Year: 2012
Aims Postfire logging recoups the economic value of timber killed by wildfire, but whether such forest management activity supports or impedes forest recovery in stands differing in structure from historic conditions remains unclear. The aim of this study was to determine the impact of mechanical logging after wildfire on soil bacterial and fungal communities and other measures influencing soil productivity. Methods We compared soil bacterial and fungal communities and biogeochemical responses of 1) soils compacted, and 2) soils compacted and then subsoiled, to 3) soils receiving no…
Publication Type: Journal Article
Using niche models with climate projections to inform conservation management decisions
Year: 2012
Conservation science strives to inform management decisions. Applying niche models in concert with future climate projections to project species vulnerability to extinction, range size loss, or distribution shifts has emerged as a potentially useful tool for informing resource management decisions. Making climate change niche modeling useful to conservation decisions requires centering studies on the types of decisions that are made regarding the focal taxa of a niche model study. Recent recommendations for climate adaptation strategies suggest four types of decision makers: policy, habitat…
Publication Type: Journal Article
Ecological effects of alternative fuel-reduction treatments: highlights of the National Fire and Fire Surrogate study (FSS)
Year: 2012
The 12-site National Fire and Fire Surrogate study (FFS) was a multivariate experiment that evaluated ecological consequences of alternative fuel-reduction treatments in seasonally dry forests of the US. Each site was a replicated experiment with a common design that compared an un-manipulated control, prescribed fire, mechanical and mechanical + fire treatments. Variables within the vegetation, fuelbed, forest floor and soil, bark beetles, tree diseases and wildlife were measured in 10-ha stands, and ecological response was compared among treatments at the site level, and across sites, to…
Publication Type: Journal Article
A Comprehensive Guide to Fuel Management practices for Dry Mixed Conifer Forests in the Northwestern United States
Year: 2012
This guide describes the benefits, opportunities, and trade-offs concerning fuel treatments in the dry mixed conifer forests of northern California and the Klamath Mountains, Pacific Northwest Interior, northern and central Rocky Mountains, and Utah. Multiple interacting disturbances and diverse physical settings have created a forest mosaic with historically low- to mixed-severity fire regimes. Analysis of forest inventory data found nearly 80 percent of these forests rate hazardous by at least one measure and 20 to 30 percent rate hazardous by multiple measures. Modeled mechanical…
Publication Type: Report
Fuels and Fire Behavior Dynamics in Bark Beetle-Attacked Forests in Western North America and Implications for Fire Management
Year: 2012
Declining forest health attributed to associations between extensive bark beetle-caused tree mortality, accumulations of hazardous fuels, wildfire, and climate change have catalyzed changes in forest health and wildfire protection policies of land management agencies. These changes subsequently prompted research to investigate the extent to which bark beetle-altered fuel complexes affect fire behavior. Although not yet rigorously quantified, the results of the investigations, in addition to a growing body of operational experience and research, indicates that predictable changes in surface,…
Publication Type: Journal Article
After the Fire is Out
Year: 2011
Even before firefighters have left a burn site, a second wave of specialists is deployed. Their task: to assess the burn site; determine the level of risk to life, property, and ecological resources; and determine quickly the most effective postfire treatments for emergency stabilization and initial rehabilitation of the site. For the past 13 years, the Joint Fire Science Program (JFSP) has funded research on this critical phase of work, which often goes unnoticed after the fire is out. With support from the JFSP, scientists have made great strides in improving the tools available to assess…
Publication Type: Report
Vegetation recovery after fire in the Klamath-Siskiyou region, southern Oregon
Year: 2011
This overview is intended to facilitate decisions regarding forest regeneration in the Klamath-Siskiyou Ecoregion. It summarizes the results of several scientific investigations that took place in the ecoregion. Some of the research occurred in areas without post-fire management, and other research occurred in moderately or intensively managed areas. Some of the research also occurred immediately after a wildfire, and other work occurred several decades later.
Publication Type: Report
Nontribal community recovery from wildfire five years later: The case of the Rodeo-Chediski fire
Year: 2011
Recent literature suggests that natural disasters such as wildfires often have the short-term effect of ‘‘bringing people together’’ while also under some circumstances generating social conflict at the local level. Conflict has been documented particularly when social relations are disembedded by nonlocal entities and there is a perceived loss of local agency. There is less agreement about longer term impacts. We present results of a re-study of a set of communities affected by the largest wildfire in Arizona history. The re-study uses structuration theory to suggest that while local…
Publication Type: Journal Article
Woodpecker Habitat After the Fire
Year: 2011
Public land managers are asked to minimize fuel levels after fires, including using techniques such as salvage logging. They are also responsible for maintaining suitable wildlife habitat, especially for species of concern to state and federal agencies. An area where these responsibilities could conflict is in the use of salvage logging in burned-over areas that also represent good habitat for certain wildlife such as woodpeckers. Controversy over this conflict has led to litigation. Public land management agencies need consistent design criteria to maintain suitable habitats for these birds…
Publication Type: Report
Evaluating Soil Risks Associated With Severe Wildfire and Ground-Based Logging
Year: 2011
Rehabilitation and timber-salvage activities after wildfire require rapid planning and rational decisions. Identifying areas with high risk for erosion and soil productivity losses is important. Moreover, allocation of corrective and mitigative efforts must be rational and prioritized. Our logic-based analysis of forested soil polygons on the Okanogan-Wenatchee National Forest was designed and implemented with the Ecosystem Management Decision Support (EMDS) system to evaluate risks to soil properties and productivity associated with moderate to severe wildfire and unmitigated use of ground-…
Publication Type: Report
Effectiveness of post-fire seeding at the Fitzner-Eberhardt Arid Land Ecology Reserve, Washington
Year: 2011
In August 2007, the Milepost 17 and Wautoma fires burned a combined total of 77,349 acres (31,302 hectares) of the Fitzner-Eberhardt Arid Land Ecology Reserve (ALE), part of the Hanford Reach National Monument administered by the U.S. Fish and Wildlife Service (USFWS) Mid-Columbia National Wildlife Refuge. In 2008, the USFWS implemented a series of seeding and herbicide treatments to mitigate potential negative consequences of these fires, including mortality of native vegetation, invasion of Bromus tectorum (cheatgrass), and soil erosion. Treatments included combinations of seeding (drill…
Publication Type: Report
Short- and Long-term Effects of Fire on Carbon in US Dry Temperate Forest Systems
Year: 2011
Forests sequester carbon from the atmosphere, and in so doing can mitigate the effects of climate change. Fire is a natural disturbance process in many forest systems that releases carbon back to the atmosphere. In dry temperate forests, fires historically burned with greater frequency and lower severity than they do today. Frequent fires consumed fuels on the forest floor and maintained open stand structures. Fire suppression has resulted in increased understory fuel loads and tree density; a change in structure that has caused a shift from low- to high-severity fires. More severe fires,…
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
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
Masticating Fuels: Effects on Prescribed Fire Behavior and Subsequent Vegetation Effects
Year: 2009
In fire management, there is an ongoing quest to find cost-effective, ecologically sound, and risk-reducing approaches to restoring dry conifer forests. So far little is known about the effectiveness of using mastication equipment in conjunction with prescribed burning to help meet management and restoration goals. Richy Harrod is the Deputy Fire Management Officer at the Okanogan-Wenatchee National Forest in Wenatchee, Washington. He and his colleagues began to address this knowledge gap and found that mastication may be a cost-effective and important tool for managers looking for additional…
Publication Type: Report
Synthesis of Knowledge on the Effects of Fire and Fire Surrogates on Wildlife in U.S. Dry Forests
Year: 2009
Dry forests throughout the United States are fire-dependent ecosystems, and much attention has been given to restoring their ecological function. As such, land managers often are tasked with reintroducing fire via prescribed fire, wildland fire use, and fire-surrogate treatments such as thinning and mastication. During planning, managers frequently are expected to anticipate effects of management actions on wildlife species. This document represents a synthesis of existing knowledge on wildlife responses to fire and fire-surrogate treatments, presented in a useful, management-relevant format…
Publication Type: Report
ArcFuels: Integrating Wildfire Models and Risk Analysis into Landscape Fuels Management
Year: 2009
That risk from wildfire continues to grow across the United States is not a new problem. Managing forest fuels in the real world—such as thinning and burning prescriptively—to reduce fuel loads have been used effectively to reduce the risk of severe wildfire. These actions have been helped by a variety of software tools that assist managers in planning and evaluating fuel treatments to ensure they are cost effective in terms of impeding the growth of future large, severe wildfires. While many landscape planning tools do a fine job within the scope of their capabilities, the process of fine…
Publication Type: Report
Estimating volume, biomass, and potential emissions of hand-piled fuels
Year: 2009
Dimensions, volume, and biomass were measured for 121 hand-constructed piles composed primarily of coniferous (n = 63) and shrub/hardwood (n = 58) material at sites in Washington and California. Equations using pile dimensions, shape, and type allow users to accurately estimate the biomass of hand piles. Equations for estimating true pile volume from simple geometric shapes and measurements of pile dimensions were also developed for users who require estimates of pile volume for regulatory reporting. Biomass and volume estimation equations were developed to allow users to estimate either…
Publication Type: Report