Research Database
Displaying 161 - 170 of 170
Pattern and process of prescribed fires influence effectiveness at reducing wildfire severity in dry coniferous forests
Year: 2012
We examined the effects of three early season (spring) prescribed fires on burn severity patterns of summer wildfires that occurred 1–3 years post- treatment in a mixed conifer forest in central Idaho. Wildfire and prescribed fire burn severities were estimated as the difference in normalized burn ratio (dNBR) using Landsat imagery. We used GIS derived vegetation, topography, and treatment variables to generate models predicting the wildfire burn severity of 1286–5500 30- m pixels within and around treated areas. We found that wildfire severity was significantly lower in treated areas than in…
Publication Type: Journal Article
Climatic, Landform, Microtopographic, and Overstory Canopy Controls of Tree Invasion in a Subalpine Meadow Landscape, Oregon Cascades, USA
Year: 2012
Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and biotic factors at multiple spatial scales. The purpose of this research was to quantify spatiotemporal patterns of meadow invasion; and how climate, larger landforms, topography, and overstory trees have interactively influenced…
Publication Type: Journal Article
Wildfire exposure to analysis on the national forests in the Pacific Northwest, USA
Year: 2012
We analyzed wildfire exposure for key social and ecological features on the national forests in Oregon and Washington. The forests contain numerous urban interfaces, old growth forests, recreational sites, and habitat for rare and endangered species. Many of these resources are threatened by wildfire, especially in the east Cascade Mountains fire-prone forests. The study illustrates the application of wildfire simulation for risk assessment where the major threat is from large and rare naturally ignited fires, versus many previous studies that have focused on risk driven by frequent and small…
Publication Type: Journal Article
Ecosystem Greenspots: Identifying Potential Drought, Fire, and Climate-Change Micro-Refuges
Year: 2012
In response to climate change and other threatening processes there is renewed interest in the role of refugia and refuges. In bioregions that experience drought and fire, micro-refuges can play a vital role in ensuring the persistence of species. We develop and apply an approach to identifying potential micro-refuges based on a time series of remotely sensed vegetation greenness (fraction of photosynthetically active radiation intercepted by the sunlit canopy; fPAR). The primary data for this analysis were NASA MODIS 16-day L3 Global 250 m (MOD13Q1) satellite imagery. This method draws upon…
Publication Type: Journal Article
Scenarios of land use and land cover change in the conterminous United States: Utilizing the special report on emission scenarios at ecoregional scales
Year: 2012
Global environmental change scenarios have typically provided projections of land use and land cover for a relatively small number of regions or using a relatively coarse resolution spatial grid, and for only a few major sectors. The coarseness of global projections, in both spatial and thematic dimensions, often limits their direct utility at scales useful for environmental management. This paper describes methods to downscale projections of land-use and land-cover change from the Intergovernmental Panel on Climate Change's Special Report on Emission Scenarios to ecological regions of the…
Publication Type: Journal Article
Both topography and climate affected forest and woodland burn severity in two regions of the western US, 1984 to 2006
Year: 2011
Fire is a keystone process in many ecosystems of western North America. Severe fires kill and consume large amounts of above- and belowground biomass and affect soils, resulting in long-lasting consequences for vegetation, aquatic ecosystem productivity and diversity, and other ecosystem properties. We analyzed the occurrence of, and trends in, satellite-derived burn severity across six ecoregions in the Southwest and Northwest regions of the United States from 1984 to 2006 using data from the Monitoring Trends in Burn Severity project. Using 1,024 fires from the Northwest (4,311,871 ha) and…
Publication Type: Journal Article
Northwest Forest Plan -- The First 15 Years: Status and Trends of Northern Spotted Owl Populations and Habitats
Year: 2011
This is the second in a series of periodic monitoring reports on northern spotted owl (Strix occidentalis caurina) population and habitat trends on federally administered lands since implementation of the Northwest Forest Plan in 1994.Here we summarize results from a population analysis that included data from long-term demographic studies during 1985–2008. This data was analyzed separately by study area, and also in a meta-analysis across all study areas to assess temporal and spatial patterns in fecundity, apparent survival, recruitment, and annual rates of population change. Estimated…
Publication Type: Report
Assessing fuel treatment effectiveness using satellite imagery and spatial statistics
Year: 2009
Understanding the influences of forest management practices on wildfire severity is critical in fire-prone ecosystems of the western United States. Newly available geospatial data sets characterizing vegetation, fuels, topography, and burn severity offer new opportunities for studying fuel treatment effectiveness at regional to national scales. In this study, we used ordinary least-squares (OLS) regression and sequential autoregression (SAR) to analyze fuel treatment effects on burn severity for three recent wildfires: the Camp 32 fire in western Montana, the School fire in southeastern…
Publication Type: Journal Article
Social Science to Improve Fuels Management: A Synthesis of Research Relevant to Communicating with Homeowners About Fuels Management
Year: 2006
The large fires in southern California during the fall of 2003 highlighted the significant fire hazard many wildland-urban interface communities and homes currently face. Despite this risk, people continue to leave metropolitan areas for the beauty and tranquility of the wildland-urban interface. The peaceful natural views instill a treasured sense of place and privacy among residents, which can make it challenging to manage the environment and reduce fuels (Lee and Tribe 1987, Lee et al. 1987, Shands 1988, Sullivan 1994, Weise and Martin 1994). Firefighting and land management agencies as…
Publication Type: Report
Social science in fuel management: an annotated bibliography of prescribed fire
Year: 2002
This annotated bibliography is collected from professional journals in natural resource management and sociology, conference proceedings, and technical reports. It is categorized into thirteen sections: acceptability, fire in wilderness, general, history, institutions, media, policy, public attitude toward wildfire, public involvement, public perception of prescribed burning, risk perception, social psychology, and wildland-urban interface.
Publication Type: Report