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• 31. [Article] Data from: Network analysis of wildfire transmission and implications for risk governance

  [Suggested citation: Ager, AA; Evers, CR; Day, MA; Preisler, HK; Barros, AM; Nielsen-Pincus, M (2017): Data from: Network analysis of wildfire transmission and implications for risk governance. OSU Libraries. ...

  Citation × Citation Citation Abstract Copy Title: Data from: Network analysis of wildfire transmission and implications for risk governance Author: Barros, AM, Preisler, HK, Ager, AA, Nielsen-Pincus, M, Day, MA, Evers, CR [Suggested citation: Ager, AA; Evers, CR; Day, MA; Preisler, HK; Barros, AM; Nielsen-Pincus, M (2017): Data from: Network analysis of wildfire transmission and implications for risk governance. OSU Libraries. Dataset. https://doi.org/10.7267/N9G15XS6] Title: Data from: Network analysis of wildfire transmission and implications for risk governance Author: Barros, AM, Preisler, HK, Ager, AA, Nielsen-Pincus, M, Day, MA, Evers, CR [Suggested citation: Ager, AA; Evers, CR; Day, MA; Preisler, HK; Barros, AM; Nielsen-Pincus, M (2017): Data from: Network analysis of wildfire transmission and implications for risk governance. OSU Libraries. Dataset. https://doi.org/10.7267/N9G15XS6] Close

• 32. [Article] Network Analysis of Wildfire Transmission and Implications for Risk Governance

  We characterized wildfire transmission and exposure within a matrix of large land tenures (federal, state, and private) surrounding 56 communities within a 3.3 million ha fire prone region of central Oregon ...

  Citation × Citation Citation Abstract Copy Title: Network Analysis of Wildfire Transmission and Implications for Risk Governance Author: Ager, Alan A., Evers, Cody, Day, Michelle A., Preisler, Haiganoush K., Barros, Ana M.G., Nielsen-Pincus, Max Year: 2017 We characterized wildfire transmission and exposure within a matrix of large land tenures (federal, state, and private) surrounding 56 communities within a 3.3 million ha fire prone region of central Oregon US. Wildfire simulation and network analysis were used to quantify the exchange of fire among land tenures and communities and analyze the relative contributions of human versus natural ignitions to wildfire exposure. Among the land tenures examined, the area burned by incoming fires averaged 57% of the total burned area. Community exposure from incoming fires ignited on surrounding land tenures accounted for 67% of the total area burned. The number of land tenures contributing wildfire to individual communities and surrounding wildland urban interface (WUI) varied from 3 to 20. Community firesheds, i.e. the area where ignitions can spawn fires that can burn into the WUI, covered 40% of the landscape, and were 5.5 times larger than the combined area of the community core and WUI. For the major land tenures within the study area, the amount of incoming versus outgoing fire was relatively constant, with some exceptions. The study provides a multi-scale characterization of wildfire networks within a large, mixed tenure and fire prone landscape, and illustrates the connectivity of risk between communities and the surrounding wildlands. We use the findings to discuss how scale mismatches in local wildfire governance result from disconnected planning systems and disparate fire management objectives among the large landowners (federal, state, private) and local communities. Local and regional risk planning processes can adopt our concepts and methods to better define and map the scale of wildfire risk from large fire events and incorporate wildfire network and connectivity concepts into risk assessments. Title: Network Analysis of Wildfire Transmission and Implications for Risk Governance Author: Ager, Alan A., Evers, Cody, Day, Michelle A., Preisler, Haiganoush K., Barros, Ana M.G., Nielsen-Pincus, Max Year: 2017 We characterized wildfire transmission and exposure within a matrix of large land tenures (federal, state, and private) surrounding 56 communities within a 3.3 million ha fire prone region of central Oregon US. Wildfire simulation and network analysis were used to quantify the exchange of fire among land tenures and communities and analyze the relative contributions of human versus natural ignitions to wildfire exposure. Among the land tenures examined, the area burned by incoming fires averaged 57% of the total burned area. Community exposure from incoming fires ignited on surrounding land tenures accounted for 67% of the total area burned. The number of land tenures contributing wildfire to individual communities and surrounding wildland urban interface (WUI) varied from 3 to 20. Community firesheds, i.e. the area where ignitions can spawn fires that can burn into the WUI, covered 40% of the landscape, and were 5.5 times larger than the combined area of the community core and WUI. For the major land tenures within the study area, the amount of incoming versus outgoing fire was relatively constant, with some exceptions. The study provides a multi-scale characterization of wildfire networks within a large, mixed tenure and fire prone landscape, and illustrates the connectivity of risk between communities and the surrounding wildlands. We use the findings to discuss how scale mismatches in local wildfire governance result from disconnected planning systems and disparate fire management objectives among the large landowners (federal, state, private) and local communities. Local and regional risk planning processes can adopt our concepts and methods to better define and map the scale of wildfire risk from large fire events and incorporate wildfire network and connectivity concepts into risk assessments. Close

• 33. [Article] Essays on the interactions between land use, natural amenity and wildfire risk

  It is essential to study the relationship between environmental features and human land-use activities that can provide a better understanding of human-environment interactions. In a response, this dissertation ...

  Citation × Citation Citation Abstract Copy Title: Essays on the interactions between land use, natural amenity and wildfire risk Author: Xu, Wenchao It is essential to study the relationship between environmental features and human land-use activities that can provide a better understanding of human-environment interactions. In a response, this dissertation addresses the human-environment issues from different perspectives in three essays. The first essay conducts an integrated analysis to investigate the impacts of human activities and environmental features on wildfire occurrence at the Wildland-Urban Interface in a changing climate. We focus on the impacts of land use changes as measured by their density, connectivity, and mix. The conceptual model builds on a theoretical framework developed by Woodward (1987) and Neilson (1995) that characterizes the functioning mechanism of ecosystems. The empirical models identify the key factors that influence wildfires. Hypotheses are tested to demonstrate the spatial heterogeneity of human land-use impacts on wildfires. Results can inform the design of policies that aim to identify community vulnerabilities, reduce wildfire uncertainties, strengthen firewise community development, and inform future land-use decision making in response to wildfire threats. The second essay analyzes the impacts of wildfire risk on urban development. It builds on and expands the monocentric-city framework developed by Wu (2006) and Wu (2010) by introducing wildfire risk into this model. We calibrate the model and examine the urban spatial profiles changes under different assumptions of wildfire risks and natural amenities. We find that wildfire risk can take on various aspects of urban spatial profiles at a much broad scale that go beyond the fire-prone areas and affects both households and public decision sectors. Even without inconsistency in fire-zone designation policy, over-development can occur in fire-hazardous area. The third essay models the role of amenity in interregional migration and spatial distribution of economic activities. Extending the new economic geography model of Helpman (1998) by including locational amenities, we present a multi-market equilibrium framework that includes consumption, production, and trade. Results suggest that the effects of amenities are significantly affected by household preferences, trade barriers, and other regional economic characteristics. This study contributes to the amenity-driven migration literatures and informs the debate about the effect of amenities on interregional migrations and regional economic development. Title: Essays on the interactions between land use, natural amenity and wildfire risk Author: Xu, Wenchao It is essential to study the relationship between environmental features and human land-use activities that can provide a better understanding of human-environment interactions. In a response, this dissertation addresses the human-environment issues from different perspectives in three essays. The first essay conducts an integrated analysis to investigate the impacts of human activities and environmental features on wildfire occurrence at the Wildland-Urban Interface in a changing climate. We focus on the impacts of land use changes as measured by their density, connectivity, and mix. The conceptual model builds on a theoretical framework developed by Woodward (1987) and Neilson (1995) that characterizes the functioning mechanism of ecosystems. The empirical models identify the key factors that influence wildfires. Hypotheses are tested to demonstrate the spatial heterogeneity of human land-use impacts on wildfires. Results can inform the design of policies that aim to identify community vulnerabilities, reduce wildfire uncertainties, strengthen firewise community development, and inform future land-use decision making in response to wildfire threats. The second essay analyzes the impacts of wildfire risk on urban development. It builds on and expands the monocentric-city framework developed by Wu (2006) and Wu (2010) by introducing wildfire risk into this model. We calibrate the model and examine the urban spatial profiles changes under different assumptions of wildfire risks and natural amenities. We find that wildfire risk can take on various aspects of urban spatial profiles at a much broad scale that go beyond the fire-prone areas and affects both households and public decision sectors. Even without inconsistency in fire-zone designation policy, over-development can occur in fire-hazardous area. The third essay models the role of amenity in interregional migration and spatial distribution of economic activities. Extending the new economic geography model of Helpman (1998) by including locational amenities, we present a multi-market equilibrium framework that includes consumption, production, and trade. Results suggest that the effects of amenities are significantly affected by household preferences, trade barriers, and other regional economic characteristics. This study contributes to the amenity-driven migration literatures and informs the debate about the effect of amenities on interregional migrations and regional economic development. Close

• 34. [Article] Wildland fire in ecosystems : effects of fire on fauna

  Fires affect animals mainly through effects on their habitat. Fires often cause short-term increases in wildlife foods that contribute to increases in populations of some animals. These increases are moderated ...

  Citation × Citation Citation Abstract Copy Title: Wildland fire in ecosystems : effects of fire on fauna Author: Schreiner, David Scott, Smith, Jane Kapler, Telfer, Edmund S., Huff, Mark H., Lyon, L. Jack, Hooper, Robert G. Fires affect animals mainly through effects on their habitat. Fires often cause short-term increases in wildlife foods that contribute to increases in populations of some animals. These increases are moderated by the animals’ ability to thrive in the altered, often simplified, structure of the postfire environment. The extent of fire effects on animal communities generally depends on the extent of change in habitat structure and species composition caused by fire. Stand-replacement fires usually cause greater changes in the faunal communities of forests than in those of grasslands. Within forests, standreplacement fires usually alter the animal community more dramatically than understory fires. Animal species are adapted to survive the pattern of fire frequency, season, size, severity, and uniformity that characterized their habitat in presettlement times. When fire frequency increases or decreases substantially or fire severity changes from presettlement patterns, habitat for many animal species declines. Title: Wildland fire in ecosystems : effects of fire on fauna Author: Schreiner, David Scott, Smith, Jane Kapler, Telfer, Edmund S., Huff, Mark H., Lyon, L. Jack, Hooper, Robert G. Fires affect animals mainly through effects on their habitat. Fires often cause short-term increases in wildlife foods that contribute to increases in populations of some animals. These increases are moderated by the animals’ ability to thrive in the altered, often simplified, structure of the postfire environment. The extent of fire effects on animal communities generally depends on the extent of change in habitat structure and species composition caused by fire. Stand-replacement fires usually cause greater changes in the faunal communities of forests than in those of grasslands. Within forests, standreplacement fires usually alter the animal community more dramatically than understory fires. Animal species are adapted to survive the pattern of fire frequency, season, size, severity, and uniformity that characterized their habitat in presettlement times. When fire frequency increases or decreases substantially or fire severity changes from presettlement patterns, habitat for many animal species declines. Close

• 35. [Article] The Schultz Fire : an interdisciplinary perspective on its history, management, and ecological effects

  This thesis examines the Schultz Fire as a case study to explain the complex history of fire suppression management in America’s forests, and to gain further understanding of how management practices have ...

  Citation × Citation Citation Abstract Copy Title: The Schultz Fire : an interdisciplinary perspective on its history, management, and ecological effects Author: Ranseen, Susanne N. This thesis examines the Schultz Fire as a case study to explain the complex history of fire suppression management in America’s forests, and to gain further understanding of how management practices have affected the increase in fire severity levels and how forests respond to such a disturbance. The thesis objectives were: (1) to analyze the causes of the fire severity of the Schultz Fire, especially: topography, fuels, or weather; (2); to examine the possible correlation between fire severity and tree density; (3) to investigate whether post-fire species richness was related to fire severity two years after the Schultz Fire; (4) to investigate whether post-fire plant species richness, plant cover, and tree regeneration was related to fire severity two years after the Schultz Fire; and (5) to interlink and convey how these factors relate to the history of fire management and policy and public perception. The history of fire related policy and management has significantly changed the dynamics of America's national parks and forests. Understanding the larger context of this history, both of national fire management and of the effects of language and perception on policy and public reaction, is part of understanding the Schultz Fire as a whole. Based on modeling, high winds combined with the presence of high surface fuel load were the main causes of the Schultz Fire's high fire severity levels. As fire severity increased there was a statistically significant increase in species richness. Severity level had little variation on percentage of cover by plants. No statistically significant relationship between tree density and fire severity levels was found. These findings underline the need for fuel treatments in southwest Ponderosa Pine forests, and effective cooperation between communities, managers, and ecologists. The Schultz Fire serves as an example in understanding the intricacies of how history affects the present and future of fire management. How fire has been managed and portrayed in the past has left an indelible mark on how fire is presently viewed. Without a clear understanding of the history of fire management and the role of fire in the ecology, future policies towards fire will be unable to account for and manage for the diversity of ecosystems and fires effects on those ecosystems across the United States. Title: The Schultz Fire : an interdisciplinary perspective on its history, management, and ecological effects Author: Ranseen, Susanne N. This thesis examines the Schultz Fire as a case study to explain the complex history of fire suppression management in America’s forests, and to gain further understanding of how management practices have affected the increase in fire severity levels and how forests respond to such a disturbance. The thesis objectives were: (1) to analyze the causes of the fire severity of the Schultz Fire, especially: topography, fuels, or weather; (2); to examine the possible correlation between fire severity and tree density; (3) to investigate whether post-fire species richness was related to fire severity two years after the Schultz Fire; (4) to investigate whether post-fire plant species richness, plant cover, and tree regeneration was related to fire severity two years after the Schultz Fire; and (5) to interlink and convey how these factors relate to the history of fire management and policy and public perception. The history of fire related policy and management has significantly changed the dynamics of America's national parks and forests. Understanding the larger context of this history, both of national fire management and of the effects of language and perception on policy and public reaction, is part of understanding the Schultz Fire as a whole. Based on modeling, high winds combined with the presence of high surface fuel load were the main causes of the Schultz Fire's high fire severity levels. As fire severity increased there was a statistically significant increase in species richness. Severity level had little variation on percentage of cover by plants. No statistically significant relationship between tree density and fire severity levels was found. These findings underline the need for fuel treatments in southwest Ponderosa Pine forests, and effective cooperation between communities, managers, and ecologists. The Schultz Fire serves as an example in understanding the intricacies of how history affects the present and future of fire management. How fire has been managed and portrayed in the past has left an indelible mark on how fire is presently viewed. Without a clear understanding of the history of fire management and the role of fire in the ecology, future policies towards fire will be unable to account for and manage for the diversity of ecosystems and fires effects on those ecosystems across the United States. Close

• 36. [Article] Historical fire regime in the Little River watershed, southwestern Oregon

  Disturbances are a prevalent and important part of ecosystems. Many landscape patterns that we find today were created, maintained, and changed by natural disturbance regimes. This is especially true for ...

  Citation × Citation Citation Abstract Copy Title: Historical fire regime in the Little River watershed, southwestern Oregon Author: Van Norman, Kelli J. Disturbances are a prevalent and important part of ecosystems. Many landscape patterns that we find today were created, maintained, and changed by natural disturbance regimes. This is especially true for fire, which has historically been a common, natural disturbance in the western U.S forests and grasslands and many other parts of the globe. I reconstructed fire history and interpreted fire regime in 117 clearcuts distributed throughout a 45,000 ha study area within the Little River watershed, an Adaptive Management Area in southwestern Oregon. Tree rings were counted on over 3,000 stumps and provided a 683-year record of fire. The study area fire regime can be characterized by its variability. The composite median fire return interval for the study area was approximately 123 years. Fire extents were not estimated, but historical fires tended to be relatively small, usually occurring within less than 2.5 km. Low and moderate severity surface fires appeared to have been more common than stand-replacement fires indicating a moderate severity fire regime with much spatial variability in severity. The fire regime has changed temporally and spatially over the fire history record. Five distinct changes in the rate of fire occurrence were identified (1490-1569, 1570- 1844, 1845-1899, 1900-1925, and 1926-1996) and associated with changes in climate and human fire ignition and fire suppression. Fires were dispersed throughout the study area, probably due to dispersed lightning ignitions and small fire extents. As a result, fire frequency was wealdy correlated with topography. However, during the 1845-1899 time period, more fires occurred at low elevations, suggesting an influence of Euro-American settler fire ignitions. Title: Historical fire regime in the Little River watershed, southwestern Oregon Author: Van Norman, Kelli J. Disturbances are a prevalent and important part of ecosystems. Many landscape patterns that we find today were created, maintained, and changed by natural disturbance regimes. This is especially true for fire, which has historically been a common, natural disturbance in the western U.S forests and grasslands and many other parts of the globe. I reconstructed fire history and interpreted fire regime in 117 clearcuts distributed throughout a 45,000 ha study area within the Little River watershed, an Adaptive Management Area in southwestern Oregon. Tree rings were counted on over 3,000 stumps and provided a 683-year record of fire. The study area fire regime can be characterized by its variability. The composite median fire return interval for the study area was approximately 123 years. Fire extents were not estimated, but historical fires tended to be relatively small, usually occurring within less than 2.5 km. Low and moderate severity surface fires appeared to have been more common than stand-replacement fires indicating a moderate severity fire regime with much spatial variability in severity. The fire regime has changed temporally and spatially over the fire history record. Five distinct changes in the rate of fire occurrence were identified (1490-1569, 1570- 1844, 1845-1899, 1900-1925, and 1926-1996) and associated with changes in climate and human fire ignition and fire suppression. Fires were dispersed throughout the study area, probably due to dispersed lightning ignitions and small fire extents. As a result, fire frequency was wealdy correlated with topography. However, during the 1845-1899 time period, more fires occurred at low elevations, suggesting an influence of Euro-American settler fire ignitions. Close

• 37. [Article] Fire exclusion effects on riparian forest dynamics in southwestern Oregon

  This is the authors' peer-reviewed final manuscript. The published version is copyrighted by Elsevier and can be found here: http://www.journals.elsevier.com/forest-ecology-and-management/#description

  Citation × Citation Citation Abstract Copy Title: Fire exclusion effects on riparian forest dynamics in southwestern Oregon Author: Shatford, Jeff P.A., Messier, Michael S., Hibbs, David E. This is the authors' peer-reviewed final manuscript. The published version is copyrighted by Elsevier and can be found here: http://www.journals.elsevier.com/forest-ecology-and-management/#description Title: Fire exclusion effects on riparian forest dynamics in southwestern Oregon Author: Shatford, Jeff P.A., Messier, Michael S., Hibbs, David E. This is the authors' peer-reviewed final manuscript. The published version is copyrighted by Elsevier and can be found here: http://www.journals.elsevier.com/forest-ecology-and-management/#description Close

• 38. [Article] The Politics of Fire and the Social Impacts of Fire Exclusion on the Klamath

  25 pages

  Citation × Citation Citation Abstract Copy Title: The Politics of Fire and the Social Impacts of Fire Exclusion on the Klamath Author: Norgaard, Kari Year: 2016, 2014 25 pages Title: The Politics of Fire and the Social Impacts of Fire Exclusion on the Klamath Author: Norgaard, Kari Year: 2016, 2014 25 pages Close

• 39. [Article] Assessing the effect of a fuel break network to reduce burnt area and wildfire risk transmission

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the International ...

  Citation × Citation Citation Abstract Copy Title: Assessing the effect of a fuel break network to reduce burnt area and wildfire risk transmission Author: Ager, Alan A., Barros, Ana M. G., Oliveira, Tiago M., Fernandes, Paulo M. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the International Association of Wildland Fire and published by CSIRO Publishing. It can be found at: http://www.publish.csiro.au/nid/114.htm Title: Assessing the effect of a fuel break network to reduce burnt area and wildfire risk transmission Author: Ager, Alan A., Barros, Ana M. G., Oliveira, Tiago M., Fernandes, Paulo M. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the International Association of Wildland Fire and published by CSIRO Publishing. It can be found at: http://www.publish.csiro.au/nid/114.htm Close

• 40. [Article] Fire-Vegetation Feedbacks and Alternative States: Common Mechanisms of Temperate Forest Vulnerability to Fire in Southern South America and New Zealand

  In the context of global warming and increasing impacts of invasive plants and animals, we examine how positive fire–vegetation feedbacks are increasing the vulnerability of pyrophobic temperate forests ...

  Citation × Citation Citation Abstract Copy Title: Fire-Vegetation Feedbacks and Alternative States: Common Mechanisms of Temperate Forest Vulnerability to Fire in Southern South America and New Zealand Author: Kitzberger, T, Perry, G. L.W., Paritsis, J., Gowda, J. H. Year: 2016 In the context of global warming and increasing impacts of invasive plants and animals, we examine how positive fire–vegetation feedbacks are increasing the vulnerability of pyrophobic temperate forests to conversion to pyrophytic non-forest vegetation in southern South America and New Zealand. We extensively review the relevant literature to reveal how these temperate southern hemisphere floras have generated similar positive fire–vegetation feedback mechanisms resulting in increased vulnerability to anthropogenically altered fire regimens. For the two regions, we address the following questions. 1. What are the major plant species, physiognomic types and functional types characteristic of pyrophytic versus pyrophobic vegetation types and how do their traits affect flammability, resistance to fire and recovery after fire? 2. What are the roles of herbivory and microclimate in enhancing fire–vegetation feedbacks? 3. Are there similarities in trends of cover type transitions in relation to altered fire regimens? 4. How are climate change, land-use trends and the effects of introduced plants and animals affecting the vulnerability of these ecosystems to fire-induced transitions to alternative stable states? Most temperate forests of New Zealand and southern South America evolved under conditions of low fire frequencies so few taxa became adapted to recurrent fire. Current dichotomous landscapes consisting of juxtaposed pyrophobic and pyrophytic vegetation types are the outcome of the expansion of fire-resilient and fire-promoting species associated with the arrival of humans. Despite considerable differences in human history and biogeographic history, the case studies presented here show remarkable parallels in life-history traits of the key pyrophobic taxa, fire–vegetation feedback mechanisms, overall ecosystem responses to anthropogenic alteration of fire regimens, and likely vulnerability to expected global change influences on future fire regimens. Title: Fire-Vegetation Feedbacks and Alternative States: Common Mechanisms of Temperate Forest Vulnerability to Fire in Southern South America and New Zealand Author: Kitzberger, T, Perry, G. L.W., Paritsis, J., Gowda, J. H. Year: 2016 In the context of global warming and increasing impacts of invasive plants and animals, we examine how positive fire–vegetation feedbacks are increasing the vulnerability of pyrophobic temperate forests to conversion to pyrophytic non-forest vegetation in southern South America and New Zealand. We extensively review the relevant literature to reveal how these temperate southern hemisphere floras have generated similar positive fire–vegetation feedback mechanisms resulting in increased vulnerability to anthropogenically altered fire regimens. For the two regions, we address the following questions. 1. What are the major plant species, physiognomic types and functional types characteristic of pyrophytic versus pyrophobic vegetation types and how do their traits affect flammability, resistance to fire and recovery after fire? 2. What are the roles of herbivory and microclimate in enhancing fire–vegetation feedbacks? 3. Are there similarities in trends of cover type transitions in relation to altered fire regimens? 4. How are climate change, land-use trends and the effects of introduced plants and animals affecting the vulnerability of these ecosystems to fire-induced transitions to alternative stable states? Most temperate forests of New Zealand and southern South America evolved under conditions of low fire frequencies so few taxa became adapted to recurrent fire. Current dichotomous landscapes consisting of juxtaposed pyrophobic and pyrophytic vegetation types are the outcome of the expansion of fire-resilient and fire-promoting species associated with the arrival of humans. Despite considerable differences in human history and biogeographic history, the case studies presented here show remarkable parallels in life-history traits of the key pyrophobic taxa, fire–vegetation feedback mechanisms, overall ecosystem responses to anthropogenic alteration of fire regimens, and likely vulnerability to expected global change influences on future fire regimens. Close