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Stephens SL, Foster DE, Battles JJ, Bernal AA, Collins BM, Hedges R, Moghaddas JJ, Roughton AT, York RA. Forest restoration and fuels reduction work: Different pathways for achieving success in the Sierra Nevada. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2024; 34:e2932. [PMID: 37948058 DOI: 10.1002/eap.2932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 06/20/2023] [Accepted: 10/03/2023] [Indexed: 11/12/2023]
Abstract
Fire suppression and past selective logging of large trees have fundamentally changed frequent-fire-adapted forests in California. The culmination of these changes produced forests that are vulnerable to catastrophic change by wildfire, drought, and bark beetles, with climate change exacerbating this vulnerability. Management options available to address this problem include mechanical treatments (Mech), prescribed fire (Fire), or combinations of these treatments (Mech + Fire). We quantify changes in forest structure and composition, fuel accumulation, modeled fire behavior, intertree competition, and economics from a 20-year forest restoration study in the northern Sierra Nevada. All three active treatments (Fire, Mech, Mech + Fire) produced forest conditions that were much more resistant to wildfire than the untreated control. The treatments that included prescribed fire (Fire, Mech + Fire) produced the lowest surface and duff fuel loads and the lowest modeled wildfire hazards. Mech produced low fire hazards beginning 7 years after the initial treatment and Mech + Fire had lower tree growth than controls. The only treatment that produced intertree competition somewhat similar to historical California mixed-conifer forests was Mech + Fire, indicating that stands under this treatment would likely be more resilient to enhanced forest stressors. While Fire reduced modeled wildfire hazard and reintroduced a fundamental ecosystem process, it was done at a net cost to the landowner. Using Mech that included mastication and restoration thinning resulted in positive revenues and was also relatively strong as an investment in reducing modeled wildfire hazard. The Mech + Fire treatment represents a compromise between the desire to sustain financial feasibility and the desire to reintroduce fire. One key component to long-term forest conservation will be continued treatments to maintain or improve the conditions from forest restoration. Many Indigenous people speak of "active stewardship" as one of the key principles in land management and this aligns well with the need for increased restoration in western US forests. If we do not use the knowledge from 20+ years of forest research and the much longer tradition of Indigenous cultural practices and knowledge, frequent-fire forests will continue to be degraded and lost.
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Affiliation(s)
- Scott L Stephens
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
| | - Daniel E Foster
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
| | - John J Battles
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
| | - Alexis A Bernal
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
| | - Brandon M Collins
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
- Center for Fire Research and Outreach, University of California, Berkeley, Berkeley, California, USA
- USDA Forest Service, Pacific Southwest Region, Vallejo, California, USA
| | - Rachelle Hedges
- Berkeley Forests, University of California, Berkeley, Berkeley, California, USA
| | | | - Ariel T Roughton
- Berkeley Forests, University of California, Berkeley, Berkeley, California, USA
| | - Robert A York
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, California, USA
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2
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Nikinmaa L, Lindner M, Cantarello E, Gardiner B, Jacobsen JB, Jump AS, Parra C, Plieninger T, Schuck A, Seidl R, Timberlake T, Waring K, Winkel G, Muys B. A balancing act: Principles, criteria and indicator framework to operationalize social-ecological resilience of forests. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 331:117039. [PMID: 36701888 DOI: 10.1016/j.jenvman.2022.117039] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 12/11/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Against a background of intensifying climate-induced disturbances, the need to enhance the resilience of forests and forest management is gaining urgency. In forest management, multiple trade-offs exist between different demands as well as across and within temporal and spatial scales. However, methods to assess resilience that consider these trade-offs are presently lacking. Here we propose a hierarchical framework of principles, criteria, and indicators to assess the resilience of a social-ecological system by focusing on the mechanisms behind resilience. This hierarchical framework balances trade-offs between mechanisms, different parts of the social-ecological system, ecosystem services, and spatial as well as temporal scales. The framework was developed to be used in a participatory manner in forest management planning. It accounts for the major parts of the forest-related social-ecological system and considers the multiple trade-offs involved. We demonstrate the utility of the framework by applying it to a landscape dominated by Norway spruce (Picea abies (L.) Karst.) in Central Europe, managed for three different management goals. The framework highlights how forest resilience varies with the pursued management goals and related management strategies. The framework is flexible and can be applied to various forest management contexts as part of a participatory process with stakeholders. It thus is an important step towards operationalizing social-ecological resilience in forest management systems.
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Affiliation(s)
- Laura Nikinmaa
- European Forest Institute, Bonn, Germany; Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium.
| | | | - Elena Cantarello
- Department of Life and Environmental Sciences, Bournemouth University, Bournemouth, United Kingdom
| | | | - Jette Bredahl Jacobsen
- Department of Food and Resource Economics, University of Copenhagen, Copenhagen, Denmark
| | - Alistair S Jump
- Biological and Environmental Sciences, University of Stirling, Stirling, United Kingdom
| | - Constanza Parra
- Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
| | - Tobias Plieninger
- Department of Agricultural Economics and Rural Development, University of Göttingen, Göttingen, Germany; Faculty of Organic Agricultural Sciences, University of Kassel, Kassel, Germany
| | | | - Rupert Seidl
- Ecosystem Dynamics and Forest Management Group, School of Life Sciences, Technical University of Munich, Munich, Germany; Berchtesgaden National Park, Berchtesgaden, Germany
| | - Thomas Timberlake
- Department of Forest and Rangeland Stewardship, Colorado State University, Fort Collins, CO, USA
| | - Kristen Waring
- School of Forestry, Northern Arizona University, Flagstaff, AZ, USA
| | - Georg Winkel
- Forest and Nature Conservation Policy Group, Wageningen University and Research, Wageningen, the Netherlands
| | - Bart Muys
- Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
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3
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Furniss TJ, Hessburg PF, Povak NA, Salter RB, Wigmosta MS. Predicting future patterns, processes, and their interactions: Benchmark calibration and validation procedures for forest landscape models. Ecol Modell 2022. [DOI: 10.1016/j.ecolmodel.2022.110099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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4
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McColl‐Gausden SC, Bennett LT, Clarke HG, Ababei DA, Penman TD. The fuel-climate-fire conundrum: How will fire regimes change in temperate eucalypt forests under climate change? GLOBAL CHANGE BIOLOGY 2022; 28:5211-5226. [PMID: 35711097 PMCID: PMC9541362 DOI: 10.1111/gcb.16283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 05/16/2022] [Accepted: 05/19/2022] [Indexed: 06/15/2023]
Abstract
Fire regimes are changing across the globe in response to complex interactions between climate, fuel, and fire across space and time. Despite these complex interactions, research into predicting fire regime change is often unidimensional, typically focusing on direct relationships between fire activity and climate, increasing the chances of erroneous fire predictions that have ignored feedbacks with, for example, fuel loads and availability. Here, we quantify the direct and indirect role of climate on fire regime change in eucalypt dominated landscapes using a novel simulation approach that uses a landscape fire modelling framework to simulate fire regimes over decades to centuries. We estimated the relative roles of climate-mediated changes as both direct effects on fire weather and indirect effects on fuel load and structure in a full factorial simulation experiment (present and future weather, present and future fuel) that included six climate ensemble members. We applied this simulation framework to predict changes in fire regimes across six temperate forested landscapes in south-eastern Australia that encompass a broad continuum from climate-limited to fuel-limited. Climate-mediated change in weather and fuel was predicted to intensify fire regimes in all six landscapes by increasing wildfire extent and intensity and decreasing fire interval, potentially led by an earlier start to the fire season. Future weather was the dominant factor influencing changes in all the tested fire regime attributes: area burnt, area burnt at high intensity, fire interval, high-intensity fire interval, and season midpoint. However, effects of future fuel acted synergistically or antagonistically with future weather depending on the landscape and the fire regime attribute. Our results suggest that fire regimes are likely to shift across temperate ecosystems in south-eastern Australia in coming decades, particularly in climate-limited systems where there is the potential for a greater availability of fuels to burn through increased aridity.
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Affiliation(s)
- Sarah C. McColl‐Gausden
- FLARE Wildfire Research, School of Ecosystem and Forest SciencesThe University of MelbourneParkvilleVictoriaAustralia
| | - Lauren T. Bennett
- FLARE Wildfire Research, School of Ecosystem and Forest SciencesThe University of MelbourneParkvilleVictoriaAustralia
| | - Hamish G. Clarke
- Centre for Environmental Risk Management of Bushfires, Centre for Sustainable Ecosystem SolutionsUniversity of WollongongWollongongNew South WalesAustralia
- NSW Bushfire Risk Management Research HubWollongongNew South WalesAustralia
- Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithNew South WalesAustralia
| | - Dan A. Ababei
- FLARE Wildfire Research, School of Ecosystem and Forest SciencesThe University of MelbourneParkvilleVictoriaAustralia
- LightTwist SoftwareMelbourneVictoriaAustralia
| | - Trent D. Penman
- FLARE Wildfire Research, School of Ecosystem and Forest SciencesThe University of MelbourneParkvilleVictoriaAustralia
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5
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Mina M, Messier C, Duveneck MJ, Fortin M, Aquilué N. Managing for the unexpected: Building resilient forest landscapes to cope with global change. GLOBAL CHANGE BIOLOGY 2022; 28:4323-4341. [PMID: 35429213 PMCID: PMC9541346 DOI: 10.1111/gcb.16197] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 01/21/2022] [Accepted: 03/19/2022] [Indexed: 06/14/2023]
Abstract
Natural disturbances exacerbated by novel climate regimes are increasing worldwide, threatening the ability of forest ecosystems to mitigate global warming through carbon sequestration and to provide other key ecosystem services. One way to cope with unknown disturbance events is to promote the ecological resilience of the forest by increasing both functional trait and structural diversity and by fostering functional connectivity of the landscape to ensure a rapid and efficient self-reorganization of the system. We investigated how expected and unexpected variations in climate and biotic disturbances affect ecological resilience and carbon storage in a forested region in southeastern Canada. Using a process-based forest landscape model (LANDIS-II), we simulated ecosystem responses to climate change and insect outbreaks under different forest policy scenarios-including a novel approach based on functional diversification and network analysis-and tested how the potentially most damaging insect pests interact with changes in forest composition and structure due to changing climate and management. We found that climate warming, lengthening the vegetation season, will increase forest productivity and carbon storage, but unexpected impacts of drought and insect outbreaks will drastically reduce such variables. Generalist, non-native insects feeding on hardwood are the most damaging biotic agents for our region, and their monitoring and early detection should be a priority for forest authorities. Higher forest diversity driven by climate-smart management and fostered by climate change that promotes warm-adapted species, might increase disturbance severity. However, alternative forest policy scenarios led to a higher functional and structural diversity as well as functional connectivity-and thus to higher ecological resilience-than conventional management. Our results demonstrate that adopting a landscape-scale perspective by planning interventions strategically in space and adopting a functional trait approach to diversify forests is promising for enhancing ecological resilience under unexpected global change stressors.
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Affiliation(s)
- Marco Mina
- Centre for Forest ResearchUniversité du Québec à MontréalMontréalQCCanada
- Institute for Alpine EnvironmentEurac ResearchBozen/BolzanoItaly
| | - Christian Messier
- Centre for Forest ResearchUniversité du Québec à MontréalMontréalQCCanada
- Institut des Sciences de la Forêt TempéréeUniversité du Québec en OutaouaisRiponQCCanada
| | - Matthew J. Duveneck
- Harvard ForestHarvard UniversityPetershamMassachusettsUSA
- Liberal Arts DepartmentNew England ConservatoryBostonMassachusettsUSA
| | - Marie‐Josée Fortin
- Department of Ecology and EvolutionUniversity of TorontoTorontoOntarioCanada
| | - Núria Aquilué
- Centre for Forest ResearchUniversité du Québec à MontréalMontréalQCCanada
- Forest Sciences and Technology Centre of Catalonia CTFCSolsonaSpain
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6
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Airey-Lauvaux C, Pierce AD, Skinner CN, Taylor AH. Changes in fire behavior caused by fire exclusion and fuel build-up vary with topography in California montane forests, USA. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 304:114255. [PMID: 34942550 DOI: 10.1016/j.jenvman.2021.114255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 12/02/2021] [Accepted: 12/05/2021] [Indexed: 06/14/2023]
Abstract
Wildfire sizes and proportions burned with high severity effects are increasing in seasonally dry forests, especially in the western USA. A critical need in efforts to restore or maintain these forest ecosystems is to determine where fuel build-up caused by fire exclusion reaches thresholds that compromise resilience to fire. Empirical studies identifying drivers of fire severity patterns in actual wildfires can be confounded by co-variation of vegetation and topography and the stochastic effects of weather and rarely consider long-term changes in fuel caused by fire exclusion. To overcome these limitations, we used a spatially explicit fire model (FlamMap) to compare potential fire behavior by topographic position in Lassen Volcanic National Park (LAVO), California, a large (43,000 ha), mountainous, unlogged landscape with extensive historical and contemporary fuels data. Fuel loads were uniformly distributed and incrementally increased across the landscape, meaning variation in fire behavior within each simulation was due to topography and among simulations, to fuels. We analyzed changes in fire line intensity (FLI) and crown fire potential as surface and canopy fuels increased from historical to contemporary levels and with percentile and actual wildfire weather conditions. Sensitivity to the influence of fuel build-up on fire behavior varied by topographic position. Steep slopes and ridges were most sensitive. At lower surface fuel loads, under pre-exclusion and contemporary canopy conditions, fire behavior was comparable and remained surface-type. As fuels increased, FLI and passive crown fire increased on steep slopes and ridgetops but remained largely unchanged on gentle slopes. Topographic variability in fire behavior was greatest with intermediate fuels. At higher surface fuel loads, under contemporary canopy fuels, passive crown fire dominated all topographic positions. With LAVO's current surface fuels, the area with potential for passive crown fire during actual fire weather increased from 6% pre-exclusion to 34% due to canopy fuel build-up. For topographically diverse landscapes, the results highlight where contemporary fire characteristics are most likely to deviate from historical patterns and may help managers prioritize locations for prescribed burning and managed wildfire to increase fire resilience in fuel rich landscapes.
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Affiliation(s)
- Catherine Airey-Lauvaux
- Department of Geography, The Pennsylvania State University, University Park, PA, 16802, United States.
| | - Andrew D Pierce
- Department of Geography, The Pennsylvania State University, University Park, PA, 16802, United States.
| | - Carl N Skinner
- Pacific Southwest Research Station, USDA Forest Service, Redding, CA, 96002, United States.
| | - Alan H Taylor
- Department of Geography, The Pennsylvania State University, University Park, PA, 16802, United States.
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7
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Hagmann RK, Hessburg PF, Prichard SJ, Povak NA, Brown PM, Fulé PZ, Keane RE, Knapp EE, Lydersen JM, Metlen KL, Reilly MJ, Sánchez Meador AJ, Stephens SL, Stevens JT, Taylor AH, Yocom LL, Battaglia MA, Churchill DJ, Daniels LD, Falk DA, Henson P, Johnston JD, Krawchuk MA, Levine CR, Meigs GW, Merschel AG, North MP, Safford HD, Swetnam TW, Waltz AEM. Evidence for widespread changes in the structure, composition, and fire regimes of western North American forests. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e02431. [PMID: 34339067 PMCID: PMC9285092 DOI: 10.1002/eap.2431] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 03/04/2021] [Accepted: 03/22/2021] [Indexed: 05/06/2023]
Abstract
Implementation of wildfire- and climate-adaptation strategies in seasonally dry forests of western North America is impeded by numerous constraints and uncertainties. After more than a century of resource and land use change, some question the need for proactive management, particularly given novel social, ecological, and climatic conditions. To address this question, we first provide a framework for assessing changes in landscape conditions and fire regimes. Using this framework, we then evaluate evidence of change in contemporary conditions relative to those maintained by active fire regimes, i.e., those uninterrupted by a century or more of human-induced fire exclusion. The cumulative results of more than a century of research document a persistent and substantial fire deficit and widespread alterations to ecological structures and functions. These changes are not necessarily apparent at all spatial scales or in all dimensions of fire regimes and forest and nonforest conditions. Nonetheless, loss of the once abundant influence of low- and moderate-severity fires suggests that even the least fire-prone ecosystems may be affected by alteration of the surrounding landscape and, consequently, ecosystem functions. Vegetation spatial patterns in fire-excluded forested landscapes no longer reflect the heterogeneity maintained by interacting fires of active fire regimes. Live and dead vegetation (surface and canopy fuels) is generally more abundant and continuous than before European colonization. As a result, current conditions are more vulnerable to the direct and indirect effects of seasonal and episodic increases in drought and fire, especially under a rapidly warming climate. Long-term fire exclusion and contemporaneous social-ecological influences continue to extensively modify seasonally dry forested landscapes. Management that realigns or adapts fire-excluded conditions to seasonal and episodic increases in drought and fire can moderate ecosystem transitions as forests and human communities adapt to changing climatic and disturbance regimes. As adaptation strategies are developed, evaluated, and implemented, objective scientific evaluation of ongoing research and monitoring can aid differentiation of warranted and unwarranted uncertainties.
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Affiliation(s)
- R. K. Hagmann
- College of the Environment‐SEFSUniversity of WashingtonSeattleWashington98195USA
- Applegate Forestry LLCCorvallisOregon97330USA
| | - P. F. Hessburg
- College of the Environment‐SEFSUniversity of WashingtonSeattleWashington98195USA
- USDA‐FS, Forestry Sciences LaboratoryPacific Northwest Research StationWenatcheeWashington98801USA
| | - S. J. Prichard
- College of the Environment‐SEFSUniversity of WashingtonSeattleWashington98195USA
| | - N. A. Povak
- USDA‐FS, Forestry Sciences LaboratoryPacific Northwest Research StationWenatcheeWashington98801USA
- USDA‐FS, Pacific Southwest Research StationPlacervilleCalifornia95667USA
| | - P. M. Brown
- Rocky Mountain Tree‐Ring ResearchFort CollinsColorado80526USA
| | - P. Z. Fulé
- School of ForestryNorthern Arizona UniversityFlagstaffArizona86011USA
| | - R. E. Keane
- Missoula Fire Sciences LaboratoryUSDA‐FS, Rocky Mountain Research StationMissoulaMontana59808USA
| | - E. E. Knapp
- USDA‐FS, Pacific Southwest Research StationReddingCalifornia96002USA
| | - J. M. Lydersen
- Fire and Resource Assessment ProgramCalifornia Department of Forestry and Fire ProtectionSacramentoCalifornia94244USA
| | | | - M. J. Reilly
- USDA‐FS, Pacific Northwest Research StationCorvallisOregon97333USA
| | - A. J. Sánchez Meador
- Ecological Restoration InstituteNorthern Arizona UniversityFlagstaffArizona86011USA
| | - S. L. Stephens
- Department of Environmental Science, Policy, and ManagementUniversity of California–BerkeleyBerkeleyCalifornia94720USA
| | - J. T. Stevens
- U.S. Geological SurveyFort Collins Science CenterNew Mexico Landscapes Field StationSanta FeNew Mexico87508USA
| | - A. H. Taylor
- Department of Geography, Earth and Environmental Systems InstituteThe Pennsylvania State UniversityUniversity ParkPennsylvania16802USA
| | - L. L. Yocom
- Department of Wildland Resources and the Ecology CenterUtah State UniversityLoganUtah84322USA
| | - M. A. Battaglia
- USDA‐FS, Rocky Mountain Research StationFort CollinsColorado80526USA
| | - D. J. Churchill
- Washington State Department of Natural ResourcesOlympiaWashington98504USA
| | - L. D. Daniels
- Department of Forest and Conservation SciencesUniversity of British ColumbiaVancouverBritish ColumbiaV6T 1Z4Canada
| | - D. A. Falk
- School of Natural Resources and the EnvironmentUniversity of ArizonaTucsonArizona85721USA
- Laboratory of Tree‐Ring ResearchUniversity of ArizonaTucsonArizona85721USA
| | - P. Henson
- Oregon Fish and Wildlife OfficeUSDI Fish & Wildlife ServicePortlandOregon97232USA
| | - J. D. Johnston
- College of ForestryOregon State UniversityCorvallisOregon97333USA
| | - M. A. Krawchuk
- College of ForestryOregon State UniversityCorvallisOregon97333USA
| | - C. R. Levine
- Spatial Informatics GroupPleasantonCalifornia94566USA
| | - G. W. Meigs
- Washington State Department of Natural ResourcesOlympiaWashington98504USA
| | - A. G. Merschel
- College of ForestryOregon State UniversityCorvallisOregon97333USA
| | - M. P. North
- USDA‐FS, Pacific Southwest Research StationMammoth LakesCalifornia93546USA
| | - H. D. Safford
- USDA‐FS, Pacific Southwest RegionVallejoCalifornia94592USA
| | - T. W. Swetnam
- Laboratory of Tree‐Ring ResearchUniversity of ArizonaTucsonArizona85721USA
| | - A. E. M. Waltz
- Ecological Restoration InstituteNorthern Arizona UniversityFlagstaffArizona86011USA
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8
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Hessburg PF, Prichard SJ, Hagmann RK, Povak NA, Lake FK. Wildfire and climate change adaptation of western North American forests: a case for intentional management. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e02432. [PMID: 34339086 PMCID: PMC9285088 DOI: 10.1002/eap.2432] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/17/2021] [Accepted: 03/03/2021] [Indexed: 05/05/2023]
Abstract
Forest landscapes across western North America (wNA) have experienced extensive changes over the last two centuries, while climatic warming has become a global reality over the last four decades. Resulting interactions between historical increases in forested area and density and recent rapid warming, increasing insect mortality, and wildfire burned areas, are now leading to substantial abrupt landscape alterations. These outcomes are forcing forest planners and managers to identify strategies that can modify future outcomes that are ecologically and/or socially undesirable. Past forest management, including widespread harvest of fire- and climate-tolerant large old trees and old forests, fire exclusion (both Indigenous and lightning ignitions), and highly effective wildfire suppression have contributed to the current state of wNA forests. These practices were successful at meeting short-term demands, but they match poorly to modern realities. Hagmann et al. review a century of observations and multi-scale, multi-proxy, research evidence that details widespread changes in forested landscapes and wildfire regimes since the influx of European colonists. Over the preceding 10 millennia, large areas of wNA were already settled and proactively managed with intentional burning by Indigenous tribes. Prichard et al. then review the research on management practices historically applied by Indigenous tribes and currently applied by some managers to intentionally manage forests for resilient conditions. They address 10 questions surrounding the application and relevance of these management practices. Here, we highlight the main findings of both papers and offer recommendations for management. We discuss progress paralysis that often occurs with strict adherence to the precautionary principle; offer insights for dealing with the common problem of irreducible uncertainty and suggestions for reframing management and policy direction; and identify key knowledge gaps and research needs.
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Affiliation(s)
- Paul F. Hessburg
- USDA‐FS, Pacific Northwest Research Station1133 N. Western AvenueWenatcheeWashington98801USA
- College of the Environment‐SEFSUniversity of WashingtonSeattleWashington98195USA
| | - Susan J. Prichard
- College of the Environment‐SEFSUniversity of WashingtonSeattleWashington98195USA
| | - R. Keala Hagmann
- College of the Environment‐SEFSUniversity of WashingtonSeattleWashington98195USA
- Applegate Forestry LLCCorvallisOregon97330USA
| | - Nicholas A. Povak
- USDA‐FS, Pacific Northwest Research Station1133 N. Western AvenueWenatcheeWashington98801USA
- USDA‐FS, Pacific Southwest Research Station2480 Carson RoadPlacervilleCalifornia95667USA
| | - Frank K. Lake
- USDA‐FS, Pacific Southwest Research Station1700 Bayview DriveArcataCalifornia95521USA
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9
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Turner MG, Braziunas KH, Hansen WD, Hoecker TJ, Rammer W, Ratajczak Z, Westerling AL, Seidl R. The magnitude, direction, and tempo of forest change in Greater Yellowstone in a warmer world with more fire. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1485] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Monica G. Turner
- Department of Integrative Biology University of Wisconsin‐Madison Madison Wisconsin 53706 USA
| | - Kristin H. Braziunas
- Department of Integrative Biology University of Wisconsin‐Madison Madison Wisconsin 53706 USA
| | - Winslow D. Hansen
- Earth Institute Columbia University New York City New York 10025 USA
| | - Tyler J. Hoecker
- Department of Integrative Biology University of Wisconsin‐Madison Madison Wisconsin 53706 USA
| | - Werner Rammer
- School of Life Sciences Technical University of Munich 85354 Freising Germany
| | - Zak Ratajczak
- Department of Biology Kansas State University Manhattan Kansas 66506‐4901 USA
| | - A. Leroy Westerling
- Sierra Nevada Research Institute and School of Engineering University of California‐Merced Merced California 95343 USA
| | - Rupert Seidl
- School of Life Sciences Technical University of Munich 85354 Freising Germany
- Berchtesgaden National Park 83471 Berchtesgaden Germany
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10
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Blankenship K, Swaty R, Hall KR, Hagen S, Pohl K, Shlisky Hunt A, Patton J, Frid L, Smith J. Vegetation dynamics models: a comprehensive set for natural resource assessment and planning in the United States. Ecosphere 2021. [DOI: 10.1002/ecs2.3484] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Kori Blankenship
- The Nature Conservancy 4245 Fairfax Drive #100 Arlington Virginia22203USA
| | - Randy Swaty
- The Nature Conservancy 4245 Fairfax Drive #100 Arlington Virginia22203USA
| | - Kimberly R. Hall
- The Nature Conservancy 4245 Fairfax Drive #100 Arlington Virginia22203USA
| | - Sarah Hagen
- The Nature Conservancy 4245 Fairfax Drive #100 Arlington Virginia22203USA
| | - Kelly Pohl
- The Nature Conservancy 4245 Fairfax Drive #100 Arlington Virginia22203USA
| | - Ayn Shlisky Hunt
- The Nature Conservancy 4245 Fairfax Drive #100 Arlington Virginia22203USA
| | - Jeannie Patton
- The Nature Conservancy 4245 Fairfax Drive #100 Arlington Virginia22203USA
| | - Leonardo Frid
- Apex Resource Management Solutions Ltd. 937 Kingsmere Avenue Ottawa OntarioK2A 3K2Canada
| | - Jim Smith
- The Nature Conservancy 4245 Fairfax Drive #100 Arlington Virginia22203USA
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11
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Landscape Design toward Urban Resilience: Bridging Science and Physical Design Coupling Sociohydrological Modeling and Design Process. SUSTAINABILITY 2021. [DOI: 10.3390/su13094666] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Given that evolving urban systems require ever more sophisticated and creative solutions to deal with uncertainty, designing for resilience in contemporary landscape architecture represents a cross-disciplinary endeavor. While there is a breadth of research on landscape resilience within the academy, the findings of this research are seldom making their way into physical practice. There are existent gaps between the objective, scientific method of scientists and the more intuitive qualitative language of designers and practitioners. The purpose of this paper is to help bridge these gaps and ultimately support an endemic process for more resilient landscape design creation. This paper proposes a framework that integrates analytic research (i.e., modeling and examination) and design creation (i.e., place-making) using processes that incorporate feedback to help adaptively achieve resilient design solutions. Concepts of Geodesign and Planning Support Systems (PSSs) are adapted as part of the framework to emphasize the importance of modeling, assessment, and quantification as part of processes for generating information useful to designers. This paper tests the suggested framework by conducting a pilot study using a coupled sociohydrological model. The relationships between runoff and associated design factors are examined. Questions on how analytic outcomes can be translated into information for landscape design are addressed along with some ideas on how key variables in the model can be translated into useful design information. The framework and pilot study support the notion that the creation of resilient communities would be greatly enhanced by having a navigable bridge between science and practice.
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Marshall LA, Falk DA. Demographic trends in community functional tolerance reflect tree responses to climate and altered fire regimes. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02197. [PMID: 32524676 DOI: 10.1002/eap.2197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 03/09/2020] [Accepted: 04/21/2020] [Indexed: 06/11/2023]
Abstract
Forests of the western United States are undergoing substantial stress from fire exclusion and increasing effects of climate change, altering ecosystem functions and processes. Changes in broad-scale drivers of forest community composition become apparent in their effect on survivorship and regeneration, driving demographic shifts. Here we take a community functional approach to forest demography, by investigating mean drought or shade functional tolerance in community assemblages. We created the Community Mean Tolerance Index (CMTI), a response metric utilizing drought/shade tolerance trade-offs to identify communities undergoing demographic change from a functional trait perspective. We applied the CMTI to Forest Inventory and Analysis data to investigate demographic trends in drought and shade tolerance across the southern Rocky Mountains. To find the major drivers of change in community tolerance within and across forest types, we compared index trends to climate and fire-exclusion-driven disturbance, and identified areas where demographic change was most pronounced. We predicted that greater shifts in drought tolerance would occur at lower forest type ecotones where climate stress is limiting and that shifts in shade tolerance would correspond to excursions from the historic fire regime leading to greater changes in forest types adapted to frequent, low-intensity fire. The CMTI was applied spatially to identify sites likely to transition to oak shrubfield, where disturbance history combined with a species-driven demographic shift toward drought tolerance. Within forest types, lower elevations are trending toward increased drought tolerance, while higher elevations are trending toward increased shade tolerance. Across forest types, CMTI difference peaked in mid-elevation ponderosa pine and mixed-conifer forests, where fire exclusion and autecology drive demographic changes. Peak CMTI difference was associated with fire exclusion in forest types adapted to frequent fire. At higher elevations, site-level stand dynamics appear to be influencing demographic tolerance trends more than broad climate drivers. Through a community demographic approach to functional traits, the CMTI highlights areas and forest types where ecosystem function is in the process of changing, before persistent vegetation type change occurs. Applied to regional plot networks, the CMTI provides an early warning of shifts in community functional processes as climate change pressures continue.
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Affiliation(s)
- L A Marshall
- School of Natural Resources and the Environment, The University of Arizona, Tucson, Arizona, 85721-0045, USA
- Laboratory of Tree-Ring Research, The University of Arizona, Tucson, Arizona, 85721-0045, USA
| | - D A Falk
- School of Natural Resources and the Environment, The University of Arizona, Tucson, Arizona, 85721-0045, USA
- Laboratory of Tree-Ring Research, The University of Arizona, Tucson, Arizona, 85721-0045, USA
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Uncovering Dryland Woody Dynamics Using Optical, Microwave, and Field Data—Prolonged Above-Average Rainfall Paradoxically Contributes to Woody Plant Die-Off in the Western Sahel. REMOTE SENSING 2020. [DOI: 10.3390/rs12142332] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Dryland ecosystems are frequently struck by droughts. Yet, woody vegetation is often able to recover from mortality events once precipitation returns to pre-drought conditions. Climate change, however, may impact woody vegetation resilience due to more extreme and frequent droughts. Thus, better understanding how woody vegetation responds to drought events is essential. We used a phenology-based remote sensing approach coupled with field data to estimate the severity and recovery rates of a large scale die-off event that occurred in 2014–2015 in Senegal. Novel low (L-band) and high-frequency (Ku-band) passive microwave vegetation optical depth (VOD), and optical MODIS data, were used to estimate woody vegetation dynamics. The relative importance of soil, human-pressure, and before-drought vegetation dynamics influencing the woody vegetation response to the drought were assessed. The die-off in 2014–2015 represented the highest dry season VOD drop for the studied period (1989–2017), even though the 2014 drought was not as severe as the droughts in the 1980s and 1990s. The spatially explicit Die-off Severity Index derived in this study, at 500 m resolution, highlights woody plants mortality in the study area. Soil physical characteristics highly affected die-off severity and post-disturbance recovery, but pre-drought biomass accumulation (i.e., in areas that benefited from above-normal rainfall conditions before the 2014 drought) was the most important variable in explaining die-off severity. This study provides new evidence supporting a better understanding of the “greening Sahel”, suggesting that a sudden increase in woody vegetation biomass does not necessarily imply a stable ecosystem recovery from the droughts in the 1980s. Instead, prolonged above-normal rainfall conditions prior to a drought may result in the accumulation of woody biomass, creating the basis for potentially large-scale woody vegetation die-off events due to even moderate dry spells.
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Hansen WD, Abendroth D, Rammer W, Seidl R, Turner MG. Can wildland fire management alter 21st-century subalpine fire and forests in Grand Teton National Park, Wyoming, USA? ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02030. [PMID: 31674698 PMCID: PMC7612770 DOI: 10.1002/eap.2030] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 08/09/2019] [Accepted: 09/16/2019] [Indexed: 06/10/2023]
Abstract
In subalpine forests of the western United States that historically experienced infrequent, high-severity fire, whether fire management can shape 21st-century fire regimes and forest dynamics to meet natural resource objectives is not known. Managed wildfire use (i.e., allowing lightning-ignited fires to burn when risk is low instead of suppressing them) is one approach for maintaining natural fire regimes and fostering mosaics of forest structure, stand age, and tree-species composition, while protecting people and property. However, little guidance exists for where and when this strategy may be effective with climate change. We simulated most of the contiguous forest in Grand Teton National Park, Wyoming, USA to ask: (1) how would subalpine fires and forest structure be different if fires had not been suppressed during the last three decades? And (2) what is the relative influence of climate change vs. fire management strategy on future fire and forests? We contrasted fire and forests from 1989 to 2098 under two fire management scenarios (managed wildfire use and fire suppression), two general circulation models (CNRM-CM5 and GFDL-ESM2M), and two representative concentration pathways (8.5 and 4.5). We found little difference between management scenarios in the number, size, or severity of fires during the last three decades. With 21st-century warming, fire activity increased rapidly, particularly after 2050, and followed nearly identical trajectories in both management scenarios. Area burned per year between 2018 and 2099 was 1,700% greater than in the last three decades (1989-2017). Large areas of forest were abruptly lost; only 65% of the original 40,178 ha of forest remained by 2098. However, forests stayed connected and fuels were abundant enough to support profound increases in burning through this century. Our results indicate that strategies emphasizing managed wildfire use, rather than suppression, will not alter climate-induced changes to fire and forests in subalpine landscapes of western North America. This suggests that managers may continue to have flexibility to strategically suppress subalpine fires without concern for long-term consequences, in distinct contrast with dry conifer forests of the Rocky Mountains and mixed conifer forest of California where maintaining low fuel loads is essential for sustaining frequent, low-severity surface fire regimes.
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Affiliation(s)
- Winslow D. Hansen
- Department of Integrative Biology, University of Wisconsin–Madison, Madison, Wisconsin 53706 USA
| | - Diane Abendroth
- Institute of Silviculture, Department of Forest- and Soil Sciences, University of Natural Resources and Life Sciences (BOKU), Vienna Austria
| | - Werner Rammer
- Grand Teton National Park, Teton Interagency Fire, Moose, Wyoming 83012 USA
| | - Rupert Seidl
- Grand Teton National Park, Teton Interagency Fire, Moose, Wyoming 83012 USA
| | - Monica G. Turner
- Department of Integrative Biology, University of Wisconsin–Madison, Madison, Wisconsin 53706 USA
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Levine CR, Cogbill CV, Collins BM, Larson AJ, Lutz JA, North MP, Restaino CM, Safford HD, Stephens SL, Battles JJ. Estimating historical forest density from land-survey data: a response to Baker and Williams (2018). ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2019; 29:e01968. [PMID: 31257657 DOI: 10.1002/eap.1968] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 05/20/2019] [Accepted: 06/14/2019] [Indexed: 06/09/2023]
Affiliation(s)
- Carrie R Levine
- Department of Environmental Science and Policy, University of California, Davis, One Shields Avenue, Davis, California, 95616, USA
| | - Charles V Cogbill
- Harvard Forest, Harvard University, 324 North Main Street, Petersham, Massachusetts, 01366, USA
| | - Brandon M Collins
- USDA Forest Service, Pacific Southwest Research Station, 1731 Research Park Drive, Davis, California, 95618, USA
- Center for Fire Research and Outreach, College of Natural Resources, University of California, Berkeley, California, 94720-3114, USA
| | - Andrew J Larson
- Department of Forest Management, University of Montana, 32 Campus Drive, Missoula, Montana, 59812, USA
| | - James A Lutz
- S. J. & Jessie E. Quinney College of Natural Resources, Utah State University, 5230 Old Main Hill, Logan, Utah, 84322-5230, USA
| | - Malcolm P North
- USDA Forest Service, Pacific Southwest Research Station, 1731 Research Park Drive, Davis, California, 95618, USA
- Department of Plant Sciences, University of California, Davis, One Shields Avenue, Davis, California, 95616, USA
| | | | - Hugh D Safford
- Department of Environmental Science and Policy, University of California, Davis, One Shields Avenue, Davis, California, 95616, USA
- USDA Forest Service, Pacific Southwest Region, 1323 Club Drive, Vallejo, California, 94592, USA
| | - Scott L Stephens
- Department of Environmental Science, Policy, and Management, University of California, 130 Mulford Hall, Berkeley, California, 94720-3114, USA
| | - John J Battles
- Department of Environmental Science, Policy, and Management, University of California, 130 Mulford Hall, Berkeley, California, 94720-3114, USA
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Coop JD, DeLory TJ, Downing WM, Haire SL, Krawchuk MA, Miller C, Parisien M, Walker RB. Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapes. Ecosphere 2019. [DOI: 10.1002/ecs2.2809] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Jonathan D. Coop
- School of Environment and Sustainability Western Colorado University Gunnison Colorado 81231 USA
| | | | - William M. Downing
- Department of Forest Ecosystems and Society Oregon State University Corvallis Oregon 97331 USA
| | - Sandra L. Haire
- Haire Laboratory for Landscape Ecology Belfast Maine 04915 USA
| | - Meg A. Krawchuk
- Department of Forest Ecosystems and Society Oregon State University Corvallis Oregon 97331 USA
| | - Carol Miller
- Aldo Leopold Wilderness Research Institute Rocky Mountain Research Station USDA Forest Service Missoula Montana 59801 USA
| | - Marc‐André Parisien
- Northern Forestry Centre Canadian Forest Service Natural Resources Canada Edmonton Alberta Canada
| | - Ryan B. Walker
- School of Environment and Sustainability Western Colorado University Gunnison Colorado 81231 USA
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Higuera PE, Metcalf AL, Miller C, Buma B, McWethy DB, Metcalf EC, Ratajczak Z, Nelson CR, Chaffin BC, Stedman RC, McCaffrey S, Schoennagel T, Harvey BJ, Hood SM, Schultz CA, Black AE, Campbell D, Haggerty JH, Keane RE, Krawchuk MA, Kulig JC, Rafferty R, Virapongse A. Integrating Subjective and Objective Dimensions of Resilience in Fire-Prone Landscapes. Bioscience 2019; 69:379-388. [PMID: 31086421 PMCID: PMC6506416 DOI: 10.1093/biosci/biz030] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Resilience has become a common goal for science-based natural resource management, particularly in the context of changing climate and disturbance regimes. Integrating varying perspectives and definitions of resilience is a complex and often unrecognized challenge to applying resilience concepts to social-ecological systems (SESs) management. Using wildfire as an example, we develop a framework to expose and separate two important dimensions of resilience: the inherent properties that maintain structure, function, or states of an SES and the human perceptions of desirable or valued components of an SES. In doing so, the framework distinguishes between value-free and human-derived, value-explicit dimensions of resilience. Four archetypal scenarios highlight that ecological resilience and human values do not always align and that recognizing and anticipating potential misalignment is critical for developing effective management goals. Our framework clarifies existing resilience theory, connects literature across disciplines, and facilitates use of the resilience concept in research and land-management applications.
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Affiliation(s)
- Philip E Higuera
- Department of Ecosystem and Conservation Sciences at the University of Montana, in Missoula
| | - Alexander L Metcalf
- Department of Society and Conservation at the University of Montana, in Missoula
| | - Carol Miller
- Aldo Leopold Wilderness Research Institute, USDA Forest Service Rocky Mountain Research Station, in Missoula
| | - Brian Buma
- Department of Ecosystem and Conservation Sciences at the University of Montana, in Missoula
| | - David B McWethy
- Department of Earth Sciences at Montana State University, in Bozeman
| | - Elizabeth C Metcalf
- Department of Society and Conservation at the University of Montana, in Missoula
| | - Zak Ratajczak
- Department of Integrative Biology at the University of Wisconsin, in Madison
| | - Cara R Nelson
- Department of Ecosystem and Conservation Sciences at the University of Montana, in Missoula
| | - Brian C Chaffin
- Department of Society and Conservation at the University of Montana, in Missoula
| | - Richard C Stedman
- Department of Natural Resources at Cornell University, in Ithaca, NY
| | - Sarah McCaffrey
- USDA Forest Service Rocky Mountain Research Station, in Fort Collins, CO
| | | | - Brian J Harvey
- Department of Integrative Biology at the University of Colorado, in Denver
- School for Environmental and Forest Sciences at the University of Washington, in Seattle
| | - Sharon M Hood
- USDA Forest Service Rocky Mountain Research Station, in Missoula
| | - Courtney A Schultz
- Department of Forest and Rangeland Stewardship at Colorado State University, in Fort Collins
| | - Anne E Black
- USDA Forest Service Rocky Mountain Research Station, in Missoula
| | - David Campbell
- USFS District Ranger from the Bitterroot National Forest, in Montana
| | - Julia H Haggerty
- Department of Earth Sciences at Montana State University, in Bozeman
| | - Robert E Keane
- USDA Forest Service Rocky Mountain Research Station, in Missoula
| | - Meg A Krawchuk
- Department of Forest Ecosystems and Society at Oregon State University, in Corvallis
| | - Judith C Kulig
- Emeritus professor affiliated with the faculty of Health Sciences at the University of Lethbridge, in Alberta
| | - Rebekah Rafferty
- Department of Society and Conservation at the University of Montana, in Missoula
| | - Arika Virapongse
- Ronin Institute for Independent Scholarship, in Boulder, Colorado
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