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Probabilistic Risk Models for Multiple Disturbances: An Example of Forest Insects and Wildfires — by mhowell — last modified 2008-09-16 03:16 PM
Building probabilistic risk models for highly random forest disturbances like wildfire and forest insect outbreaks is a challenging problem.
Introduction — by mhowell — last modified 2008-09-24 07:09 PM
Wildfire and insect infestations are two major disturbances of forest lands in the United States.
Methods — by mhowell — last modified 2008-09-24 07:39 PM
Our study area was Oregon and Washington National Forest lands.
Probability Framework — by mhowell — last modified 2008-09-24 09:10 PM
We are interested in obtaining estimates of disturbance probabilities in the presence of multiple stressors.
Results and Discussion — by mhowell — last modified 2008-09-24 10:34 PM
The models in equations [1] and [2] appeared to give reasonable fits to 1982-2004 data on bark beetle attacks and wildfire sizes on Forest Service lands in Region 6.
Bark Beetle Infestation — by mhowell — last modified 2008-09-24 10:07 PM
The probability of beetle infestation was significantly influenced by spatial location, size of infestation in previous year, and size of 1- year-old fire within 1 km.
Fire Size — by mhowell — last modified 2008-09-24 10:33 PM
The estimated spatial pattern of fire sizes seems to indicate northern Washington and eastern Oregon as some of the regions with the highest probabilities of a fire getting large after controlling for all other predictors in the model.
Conclusions — by mhowell — last modified 2008-09-08 10:52 AM
Multiple disturbances, such as wildfire-insect outbreak interactions, are not well understood at provincial scales.
Integration of Population Genetic Structure and Plant Response to Climate Change: Sustaining Genetic Resources Through Evaluation of Projected Threats — by mhowell — last modified 2008-09-18 02:57 PM
To assess threats or predict responses to disturbances, or both, it is essential to recognize and characterize the population structures of forest species in relation to changing environments.
Introduction — by mhowell — last modified 2008-09-27 11:47 PM
Climate change and associated glacial/interglacial cycles have had a profound impact on the biogeography of plant communities.
Material and Methods — by mhowell — last modified 2008-09-28 12:04 AM
This section reviews Population Genetic Analyses and Plant-Climate Modeling.
Results — by mhowell — last modified 2008-09-28 12:10 AM
Population genetics and plant-climate modeling results are summarized for both the whitebark and western white pine.
Whitebark Pine — by mhowell — last modified 2008-09-28 12:22 AM
Analysis of mtDNA reveals three haplotypes that are discretely partitioned among regions with two introgression zones.
Western White Pine — by mhowell — last modified 2008-09-28 12:25 AM
Analyses of AFLP loci discern three metapopulations in western white pine.
Discussion — by mhowell — last modified 2008-09-28 12:29 AM
This section discusses the study findings regarding Whitebark Pine and Western White Pine, and reviews Model Refinements and Uncertainties.
Whitebark Pine — by mhowell — last modified 2008-09-28 12:40 AM
Past climate change has shaped the biogeography of whitebark pine and, hence, genetic relationships and potential adaptive traits.
Western White Pine — by mhowell — last modified 2008-09-28 12:47 AM
Like whitebark pine, western white pine populations were also shaped by past climate change.
Model Refinements and Uncertainties — by mhowell — last modified 2008-09-02 05:05 PM
Bryce A. Richardson, Marcus V. Warwell, Mee-Sook Kim, Ned B. Klopfenstein and Geral I. McDonald
Summary — by mhowell — last modified 2008-09-02 05:05 PM
Bryce A. Richardson, Marcus V. Warwell, Mee-Sook Kim, Ned B. Klopfenstein and Geral I. McDonald
Assessment of Habitat Threats to Shrublands in the Great Basin — by mhowell — last modified 2008-09-18 02:58 PM
The sagebrush (Artemisia spp.) ecosystem is one of the most imperiled in the United States.
Setting the Stage: Shrublands at Risk — by mhowell — last modified 2008-09-25 11:11 AM
The vast shrublands of Western North America, including the sagebrush (Artemisia spp.) ecosystem, provide a wide range of resource values, including recreation, livestock grazing, mining, energy extraction, wildlife habitat, and wilderness.
Status and Threats in the Sagebrush Ecosystem — by mhowell — last modified 2008-09-25 11:30 AM
The sagebrush ecosystem covers more than 43 million ha within the Western United States and Canada and constitutes one of the largest ecosystems in North America.
Ecological Setting and Status of the Great Basin — by mhowell — last modified 2008-09-25 11:35 AM
The Great Basin ecoregion spans more than 29 million ha from the eastern Sierra Nevada Mountains in California to central Utah east of the Great Salt Lake.
Regional Assessment of Habitats — by mhowell — last modified 2008-09-25 11:36 AM
To address concerns about ongoing degradation of sagebrush habitats and associated species, Wisdom and others (2005a) identified steps for spatial analysis to be used in regional assessment.
Selecting and Grouping Species of Concern — by mhowell — last modified 2008-09-25 11:42 AM
Using a variety of screening criteria, (e.g., habitat association, estimated risk of extirpation), Wisdom and others (2005a) compiled a comprehensive list of more than 350 sagebrush-associated species of concern.
Describing Species-habitat Relationships — by mhowell — last modified 2008-09-25 11:44 AM
Evaluation of the condition, (e.g., risk levels) and spatial pattern of habitat for multiple species of concern provides essential context for the development of regionally based management and conservation strategies.
Identifying Regional Threats — by mhowell — last modified 2008-09-25 11:46 AM
Wisdom and others (2005a) outlined a process for identifying threats to consider in regional assessment, using criteria such as spatial extent of the threat, available resources to address the threat, and cost-benefit analysis.
Quantifying Vegetation and Habitat in the Great Basin — by mhowell — last modified 2008-09-25 12:16 PM
To estimate vegetation at risk in the Great Basin, we first quantified the total area of each landcover type present in the study area using the landcover map.
Modeling of Displacement by Woodlands and Cheatgrass — by mhowell — last modified 2008-09-25 11:58 AM
We developed two independent, rule-based predictive models of displacement of sagebrush and other native vegetation by encroaching pinyon-juniper woodlands and cheatgrass, employing a variety of topographic and vegetation variables.
Model Development — by mhowell — last modified 2008-09-25 12:02 PM
This section describes the Pinyon-Juniper Woodland and Cheatgrass Models.
Results of Model Application in the Great Basin — by mhowell — last modified 2008-09-25 12:10 PM
Outputs from both the pinyon-juniper and cheatgrass models were summarized by landcover type and by species, (i.e., habitats at risk).
Application of Risk Models in Shrubland Management — by mhowell — last modified 2008-09-25 12:13 PM
Federal agencies need information about habitat requirements and conditions for species and groups of species at spatial extents that are typically used in land management planning.
Characterizing Habitat Conditions — by mhowell — last modified 2008-09-25 12:15 PM
We used two habitat variables, habitat abundance and habitat at risk of displacement by cheatgrass, to characterize the composite habitat conditions for each species group at the watershed extent within the Great Basin.
Prioritizing Restoration Activities — by mhowell — last modified 2008-09-25 12:17 PM
Different combinations of habitat abundance and habitat risk have different implications for conservation and restoration.
Integration of Multiple Stressors — by mhowell — last modified 2008-09-25 12:20 PM
The combined risk of displacement by cheatgrass and by pinyon-juniper woodlands was evaluated for the 4.8 million ha of sagebrush in the three ecological provinces in which the pinyon-juniper model was applied.
Management Implications — by mhowell — last modified 2008-09-02 05:05 PM
Mary M. Rowland; Lowell H. Suring; Michael J. Wisdom
Establishing a Nationwide Baseline of Historical Burn Severity Data to Support Monitoring of Trends in Wildfire Effects and National Fire Policies — by mhowell — last modified 2008-09-25 12:33 PM
There is a need to provide agency leaders, elected officials, and the general public with summary information regarding the effects of large wildfires.
Introduction — by mhowell — last modified 2008-09-25 12:35 PM
Consistent geospatial information characterizing effects of large wildland fires does not exist for lands within the United States.
Project Background — by mhowell — last modified 2008-09-25 12:36 PM
In 2006, WFLC sponsored a 6- year project to map the fire severity and perimeters on large fires (>500 acres in the East and 1000 acres in the West) in the United States across all ownerships for the period of 1984 through 2010.
Burn Severity Definition — by mhowell — last modified 2008-09-02 05:05 PM
Brian Schwind, Ken Brewer, Brad Quayle and Jeffery C. Eidenshink
Project Scope — by mhowell — last modified 2008-09-25 12:39 PM
The project has been divided into geographic mapping zones representing broadly similar ecological conditions.
Products — by mhowell — last modified 2008-09-27 05:27 PM
Unclassified or input data are comprised of Landsat TM and ETM images that form the basis for measuring spectral response of individual fires.
Methods — by mhowell — last modified 2008-09-27 04:56 PM
Methods selection for this project was fundamentally driven by two requirements: (1) The need to develop consistent information across all lands within the project extent, and (2) the need to develop consistent information spanning a significant historical period.
Fire History Database Compilation — by mhowell — last modified 2008-09-27 05:01 PM
Existing fire history and location databases were compiled into a single, standardized project database that formed the basis for image scene selection.
Image Scene Selection and Data Preprocessing — by mhowell — last modified 2008-09-08 11:24 AM
Scene selection is driven by the MTBS fire history database.
Fire Severity and Perimeter Mapping — by mhowell — last modified 2008-09-27 05:09 PM
The NBR index is calculated for prefire and postfire images.
Data Summarization — by mhowell — last modified 2008-09-27 05:15 PM
Tabular data will be generated from statistical summaries of the fire severity class layers.
Data Distribution — by mhowell — last modified 2008-09-02 05:05 PM
Brian Schwind, Ken Brewer, Brad Quayle and Jeffery C. Eidenshink
Applications for Fire Severity Data — by mhowell — last modified 2008-09-27 05:22 PM
Central to the missions of both the Western Wildland Environmental Threat Assessment Center and the Eastern Forest Environmental Threat Assessment Center is the early detection, identification, and assessment of multiple environmental threats such as insects, disease, invasive species, fire, loss or degradation of forests, and weather-related risks.
Conclusions — by mhowell — last modified 2008-09-02 05:05 PM
Brian Schwind, Ken Brewer, Brad Quayle and Jeffery C. Eidenshink
Threats to Private Forest Lands in the U.S.A.: A Forests on the Edge Study — by mhowell — last modified 2008-09-18 02:51 PM
The Forests on the Edge project, sponsored by the USDA Forest Service, uses geographic information systems to construct and analyze maps depicting threats to the contributions of America's private forest lands.
Introduction — by mhowell — last modified 2008-09-22 12:09 PM
America's forest lands contribute in a myriad of ways to the economic, ecological, and social well-being of the Nation.
Data Layers — by mhowell — last modified 2008-09-27 09:55 PM
All data layers were obtained as or constructed to be nationally consistent and were summarized at the spatial scale of fourth-level watersheds.
Private Forest Contributions — by mhowell — last modified 2008-09-27 09:35 PM
This section reviews Private Forest Land, Water Quality, Timber Supply, At-risk Species, and Interior Forest/Habitat Contiguity.
Threats to Private Forest Lands — by mhowell — last modified 2008-09-27 09:53 PM
This section reviews Development, Wildfire, Ozone, Acid Deposition, Insects Pests and Disease.
Methods — by mhowell — last modified 2008-09-02 05:05 PM
Susan M. Stein, Mark H. Hatfield, Ronald E. McRoberts, Dacia M. Meneguzzo and Sara Comas
Results — by mhowell — last modified 2008-09-27 09:57 PM
The results are briefly discussed.
Contributions — by mhowell — last modified 2008-09-27 09:59 PM
Watersheds with the greatest percentages of private forest land are generally in New England, the Southeast, and the Pacific Northwest.
Threats — by mhowell — last modified 2008-09-27 10:02 PM
Development threats to private forest land area are concentrated in southern New England and the Southeast, although some are also found in the Pacific Northwest; wildfire threats to private forest land, are primarily in the Northeastern quadrant of the country.
Conclusions — by mhowell — last modified 2008-09-08 11:49 AM
The FOTE spatial approach to assessing threats to the contributions of private forest lands produces useful, visual information that is relatively easy to obtain.
A Spatial Model for Predicting Effects of Climate Change on Swiss Needle Cast Disease Severity in Pacific Northwest Forests — by mhowell — last modified 2008-09-18 02:52 PM
Swiss needle cast disease of Douglas-fir (Pseudotsuga menziesii) is caused by the ascomycete fungus Phaeocryptopus gaeumannii.
History of the Problem — by mhowell — last modified 2008-09-27 10:13 PM
Swiss needle cast disease of Douglas-fir is caused by the ascomycete Phaeocryptopus gaeumannii (Rohde) Petrak.
Current Extent and Impacts of Swiss Needle Cast in Pacific Northwest Forests — by mhowell — last modified 2008-09-27 10:22 PM
Since around 1990, unusually severe and persistent symptoms of Swiss needle cast have been observed in Douglas-fir forest plantations in western Oregon, particularly near the town of Tillamook.
Understanding the Disease — by mhowell — last modified 2008-09-27 10:30 PM
To better understand which environmental factors might be important regulators of P. gaeumannii abundance and how they affect the epidemiology of Swiss needle cast, it was essential to investigate the infection cycle of the pathogen and its mechanism of pathogenicity.
Experimental Approaches to Understanding Climate-Disease Interactions — by mhowell — last modified 2008-09-27 10:33 PM
Because the most severe disease has been observed in sites within the low elevation coastal fog zone, the presence of free water on needle surfaces during the summer has been considered a possible factor affecting disease severity.
Modeling Swiss Needle Cast — by mhowell — last modified 2008-09-27 10:38 PM
The finding that small differences in temperature could affect rates of needle colonization and fungal development over the 11-month incubation period of P. gaeumannii prompted us to examine the effect of temperature in relation to infection data from field sites in western Oregon.
Conclusions — by mhowell — last modified 2008-09-27 11:02 PM
Improved understanding of the effects of climate factors on P. gaeumannii abundance now helps to clarify the underlying causes for recently observed increases in Swiss needle cast in the Western Coast Range.
Initial Stand Conditions — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
Regeneration Status — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
Residual Basal Area — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
Developmental Dynamics — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
Marking Rules — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
Other Considerations — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
History — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
Land Use — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
Forest Area & Conditions — by Cole Sherer — last modified 2008-06-20 01:17 PM
 
Conversions of Forest Lands: Trends, Determinants, and Policy Considerations — by Cole Sherer — last modified 2008-06-20 01:17 PM