Research Database
Displaying 141 - 160 of 216
Spatiotemporal dynamics of simulated wildfire, forest management, and forest succession in central Oregon, USA.
Year: 2017
We use the simulation model Envision to analyze long-term wildfire dynamics and the effects of different fuel management scenarios in central Oregon, USA. We simulated a 50-year future where fuel management activities were increased by doubling and tripling the current area treated while retaining existing treatment strategies in terms of spatial distribution and treatment type. We modeled forest succession using a state-and-transition approach and simulated wildfires based on the contemporary fire regime of the region. We tested for the presence of temporal trends and overall differences in…
Publication Type: Journal Article
An empirical machine learning method for predicting potential fire control locations for pre-fire planning and operational fire management
Year: 2017
During active fire incidents, decisions regarding where and how to safely and effectively deploy resources to meet management objectives are often made under rapidly evolving conditions, with limited time to assess management strategies or for development of backup plans if initial efforts prove unsuccessful. Under all but the most extreme fire weather conditions, topography and fuels are significant factors affecting potential fire spread and burn severity. We leverage these relationships to quantify the effects of topography, fuel characteristics, road networks and fire suppression effort…
Publication Type: Journal Article
Climate, wildfire, and erosion ensemble foretells more sediment in western USA watersheds
Year: 2017
The area burned annually by wildfires is expected to increase worldwide due to climate change. Burned areas increase soil erosion rates within watersheds, which can increase sedimentation in downstream rivers and reservoirs. However, which watersheds will be impacted by future wildfires is largely unknown. Using an ensemble of climate, fire, and erosion models, we show that postfire sedimentation is projected to increase for nearly nine tenths of watersheds by >10% and for more than one third of watersheds by >100% by the 2041 to 2050 decade in the western USA. The projected increases…
Publication Type: Journal Article
Post-fire vegetation and fuel development influences fire severity patterns in reburns
Year: 2017
In areas where fire regimes and forest structure have been dramatically altered, there is increasing concern that contemporary fires have the potential to set forests on a positive feedback trajectory with successive reburns, one in which extensive stand-replacing fire could promote more stand-replacing fire. Our study utilized an extensive set of field plots established following four fires that occurred between 2000 and 2010 in the northern Sierra Nevada, California, USA that were subsequently reburned in 2012. The information obtained from these field plots allowed for a unique set of…
Publication Type: Journal Article
Spatially explicit measurements of forest structure and fire behavior following restoration treatments in dry forests
Year: 2017
Restoration treatments in dry forests of the western US often attempt silvicultural practices to restore the historical characteristics of forest structure and fire behavior. However, it is suggested that a reliance on non-spatial metrics of forest stand structure, along with the use of wildland fire behavior models that lack the ability to handle complex structures, may lead to uncharacteristically homogeneous rather than heterogeneous forest structures following restoration. In our study, we used spatially explicit forest inventory data and a physics based fire behavior model to investigate…
Publication Type: Journal Article
Using an agent-based model to examine forest management outcomes in a fire-prone landscape in Oregon, USA.
Year: 2017
Fire-prone landscapes present many challenges for both managers and policy makers in developing adaptive behaviors and institutions. We used a coupled human and natural systems framework and an agent-based landscape model to examine how alternative management scenarios affect fire and ecosystem services metrics in a fire-prone multiownership landscape in the eastern Cascades of Oregon. Our model incorporated existing models of vegetation succession and fire spread and information from original empirical studies of landowner decision making. Our findings indicate that alternative management…
Publication Type: Journal Article
After the Fire Workshop: Connecting People, Ideas and Organizations
Year: 2017
Fire adaptation is about more than pre-fire work. It’s also about considering the needs of a community and the land post-fire. In Washington State, the last several fire seasons have given communities lots of opportunities to learn about post-fire recovery. Last month, members of organizations that work on community issues, landscape resilience and disaster-recovery gathered to share some of the things they’ve learned.
Publication Type: Report
Quantifying the influence of previously burned areas on suppression effectiveness and avoided exposure: a case study of the Las Conchas Fire
Year: 2016
We present a case study of the Las Conchas Fire (2011) to explore the role of previously burned areas (wildfires and prescribed fires) on suppression effectiveness and avoided exposure. Methodological innovations include characterisation of the joint dynamics of fire growth and suppression activities, development of a fire line effectiveness framework, and quantification of relative fire line efficiencies inside and outside of previously burned areas. We provide descriptive statistics of several fire line effectiveness metrics. Additionally, we leverage burn probability modelling to examine…
Publication Type: Journal Article
Mapping post-fire habitat characteristics through the fusion of remote sensing tools
Year: 2016
Post-fire snags provide important resources for cavity nesting communities as well as being subject to timber removal through salvage logging practices. Tools that can characterize their distributions along with other features important as wildlife habitat, such as woody shrub cover, would be useful for research and management purposes. Three dimensional lidar data and Landsat time series disturbance products have both shown varying promise in their ability to characterize aspects of dead biomass and understory cover, but studies exploring the combination of the remote sensing datasets…
Publication Type: Journal Article
Recovery and adaptation after wildfire on the Colorado Front Range (2010-2012)
Year: 2016
Following the loss of homes to wildfire, when risk has been made apparent, homeowners must decide whether to rebuild, and choose materials and vegetation, while local governments guide recovery and rebuilding. As wildfires are smaller and more localised than other disasters, it is unclear if recovery after wildfire results in policy change and adaptation, decreasing assets at risk, or if recovery encourages reinvestment in hazard-prone areas. We studied three wildfires on the Colorado Front Range from2010 to 2012 that each destroyed over 150homes, describing policy response and characterising…
Publication Type: Journal Article
Post-fire morel (Morchella) mushroom abundance, spatial structure, and harvest sustainability
Year: 2016
Morel mushrooms are globally distributed, socially and economically important reproductive structures produced by fungi of the genus Morchella. Morels are highly prized edible mushrooms and significant harvests are collected throughout their range, especially in the first year after fire, when some morel species fruit prolifically. Few studies have quantified post-fire morel mushroom abundance, despite their widespread human use. The purpose of this study is to provide the first ever estimate of post-fire morel mushroom abundance in Sierra Nevada mixed-conifer forest. Specifically, we…
Publication Type: Journal Article
Climate-driven changes in forest succession and the influence of management on forest carbon dynamics in the Puget Lowlands of Washington State, USA
Year: 2016
Projecting the response of forests to changing climate requires understanding how biotic and abiotic controls on tree growth will change over time. As temperature and interannual precipitation variability increase, the overall forest response is likely to be influenced by species-specific responses to changing climate. Management actions that alter composition and density may help buffer forests against the effects of changing climate, but may require tradeoffs in ecosystem services. We sought to quantify how projected changes in climate and different management regimes would alter the…
Publication Type: Journal Article
Incorporating Anthropogenic Influences into Fire Probability Models: Effects of Human Activity and Climate Change on Fire Activity in California
Year: 2016
The costly interactions between humans and wildfires throughout California demonstrate the need to understand the relationships between them, especially in the face of a changing climate and expanding human communities. Although a number of statistical and process-based wildfire models exist for California, there is enormous uncertainty about the location and number of future fires, with previously published estimates of increases ranging from nine to fifty-three percent by the end of the century. Our goal is to assess the role of climate and anthropogenic influences on the state’s fire…
Publication Type: Journal Article
Post-fire logging produces minimal persistent impacts on understory vegetation in northeastern Oregon, USA
Year: 2016
Post-fire forest management commonly requires accepting some negative ecological impacts from management activities in order to achieve management objectives. Managers need to know, however,whether ecological impacts from post-fire management activities are transient or cause long-term ecosystem degradation. We studied the long-term response of understory vegetation to two post-fire loggingtreatments – commercial salvage logging with and without additional fuel reduction logging – on a long-term post-fire logging experiment in northeastern Oregon, USA. We sampled understory plant coverand…
Publication Type: Journal Article
1984–2010 trends in fire burn severity and area for the conterminous US
Year: 2016
Burn severity products created by the Monitoring Trends in Burn Severity (MTBS) project were used to analyse historical trends in burn severity. Using a severity metric calculated by modelling the cumulative distribution of differenced Normalized Burn Ratio (dNBR) and Relativized dNBR (RdNBR) data, we examined burn area and burn severity of 4893 historical fires (1984–2010) distributed across the conterminous US (CONUS) and mapped by MTBS. Yearly mean burn severity values (weighted by area), maximum burn severity metric values, mean area of burn, maximum burn area and total burn area were…
Publication Type: Journal Article
Impact of anthropogenic climate change on wildfire across western US forests
Year: 2016
Increased forest fire activity across the western continental United States (US) in recent decades has likely been enabled by a number of factors, including the legacy of fire suppression and human settlement, natural climate variability, and human-caused climate change. We use modeled climate projections to estimate the contribution of anthropogenic climate change to observed increases in eight fuel aridity metrics and forest fire area across the western United States. Anthropogenic increases in temperature and vapor pressure deficit significantly enhanced fuel aridity across western US…
Publication Type: Journal Article
Wildland fire deficit and surplus in the western United States, 1984-2012
Year: 2015
Wildland fire is an important disturbance agent in the western US and globally. However, the natural role of fire has been disrupted in many regions due to the influence of human activities, which have the potential to either exclude or promote fire, resulting in a "fire deficit" or "fire surplus", respectively. In this study, we developed a model of expected area burned for the western US as a function of climate from 1984 to 2012. We then quantified departures from expected area burned to identify geographic regions with fire deficit or surplus. We developed our model of area burned as a…
Publication Type: Journal Article
Projected major fire and vegetation changes in the Pacific Northwest of the conterminous United States under selected CMIP5 climate futures
Year: 2015
Climate change adaptation and mitigation require understanding of vegetation response to climate change. Using the MC2 dynamic global vegetation model (DGVM) we simulate vegetation for the Northwest United States using results from 20 different Climate Model Intercomparison Project Phase 5 (CMIP5) models downscaled using the MACA algorithm. Results were generated for representative concentration pathways (RCPs) 4.5 and 8.5 under vegetation modeling scenarios with and without fire suppression for a total of 80 model runs for future projections. For analysis, results were aggregated by three…
Publication Type: Journal Article
A review of the challenges and opportunities in estimating above ground forest biomass using tree-level models
Year: 2015
Accurate biomass measurements and analyses are critical components in quantifying carbon stocks and sequestration rates, assessing potential impacts due to climate change, locating bio-energy processing plants, and mapping and planning fuel treatments. To this end, biomass equations will remain a key component of future carbon measurements and estimation. As researchers in biomass and carbon estimation, we review the present scenario of aboveground biomass estimation, focusing particularly on estimation using tree-level models and identify some cautionary points that we believe will improve…
Publication Type: Journal Article
Modeling spatial and temporal dynamics of wind flow and potential fire behavior following a mountain pine beetle outbreak in a lodgepole pine forest
Year: 2015
Patches of live, dead, and dying trees resulting from bark beetle-caused mortality alter spatial and temporal variability in the canopy and surface fuel complex through changes in the foliar moisture content of attacked trees and through the redistribution of canopy fuels. The resulting heterogeneous fuels complexes alter within-canopy wind flow, wind fluctuations, and rate of fire spread. However, there is currently little information about the potential influence of different rates and patterns of mortality on wind flow and fire behavior following bark beetle outbreaks. In this study, we…
Publication Type: Journal Article
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