1
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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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2
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Ziegler JP, Hoffman CM, Collins BM, Knapp EE, Mell W(R. Pyric tree spatial patterning interactions in historical and contemporary mixed conifer forests, California, USA. Ecol Evol 2021; 11:820-834. [PMID: 33520169 PMCID: PMC7820164 DOI: 10.1002/ece3.7084] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/23/2020] [Accepted: 11/12/2020] [Indexed: 11/30/2022] Open
Abstract
Tree spatial patterns in dry coniferous forests of the western United States, and analogous ecosystems globally, were historically aggregated, comprising a mixture of single trees and groups of trees. Modern forests, in contrast, are generally more homogeneous and overstocked than their historical counterparts. As these modern forests lack regular fire, pattern formation and maintenance is generally attributed to fire. Accordingly, fires in modern forests may not yield historically analogous patterns. However, direct observations on how selective tree mortality among pre-existing forest structure shapes tree spatial patterns is limited. In this study, we (a) simulated fires in historical and contemporary counterpart plots in a Sierra Nevadan mixed-conifer forest, (b) estimated tree mortality, and (c) examined tree spatial patterns of live trees before and after fire, and of fire-killed trees. Tree mortality in the historical period was clustered and density-dependent, because trees were aggregated and segregated by tree size before fire. Thus, fires maintained an aggregated distribution of tree groups. Tree mortality in the contemporary period was widespread, except for dispersed large trees, because most trees were a part of large, interconnected tree groups. Thus, postfire tree patterns were more uniform and devoid of moderately sized tree groups. Postfire tree patterns in the historical period, unlike the contemporary period, were within the historical range of variability identified for the western United States. This divergence suggests that decades of forest dynamics without significant disturbances have altered the historical means of pyric pattern formation. Our results suggest that ecological silvicultural treatments, such as forest restoration thinnings, which emulate qualities of historical forests may facilitate the reintroduction of fire as a means to reinforce forest structural heterogeneity.
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Affiliation(s)
- Justin P. Ziegler
- Department of Forest & Rangeland StewardshipColorado State UniversityFort CollinsCOUSA
| | - Chad M. Hoffman
- Department of Forest & Rangeland StewardshipColorado State UniversityFort CollinsCOUSA
| | - Brandon M. Collins
- Center for Fire Research & OutreachUniversity of CaliforniaBerkeleyCAUSA
- Pacific Southwest Research StationUS Forest ServiceDavisCAUSA
| | - Eric E. Knapp
- Pacific Southwest Research StationUS Forest ServiceReddingCAUSA
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3
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Ritter SM, Hoffman CM, Battaglia MA, Stevens‐Rumann CS, Mell WE. Fine‐scale fire patterns mediate forest structure in frequent‐fire ecosystems. Ecosphere 2020. [DOI: 10.1002/ecs2.3177] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Scott M. Ritter
- Department of Forest and Rangeland Stewardship Warner College of Natural Resources Colorado State University Fort Collins Colorado 80523USA
| | - Chad M. Hoffman
- Department of Forest and Rangeland Stewardship Warner College of Natural Resources Colorado State University Fort Collins Colorado 80523USA
| | - Mike A. Battaglia
- Rocky Mountain Research Station USDA Forest Service Fort Collins Colorado 80526USA
| | - Camille S. Stevens‐Rumann
- Department of Forest and Rangeland Stewardship Warner College of Natural Resources Colorado State University Fort Collins Colorado 80523USA
| | - William E. Mell
- Pacific Northwest Research Station USDA Forest Service Seattle Washington 98103USA
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4
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Dove NC, Safford HD, Bohlman GN, Estes BL, Hart SC. High-severity wildfire leads to multi-decadal impacts on soil biogeochemistry in mixed-conifer forests. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02072. [PMID: 31925848 DOI: 10.1002/eap.2072] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 09/09/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
During the past century, systematic wildfire suppression has decreased fire frequency and increased fire severity in the western United States of America. While this has resulted in large ecological changes aboveground such as altered tree species composition and increased forest density, little is known about the long-term, belowground implications of altered, ecologically novel, fire regimes, especially on soil biological processes. To better understand the long-term implications of ecologically novel, high-severity fire, we used a 44-yr high-severity fire chronosequence in the Sierra Nevada where forests were historically adapted to frequent, low-severity fire, but were fire suppressed for at least 70 yr. High-severity fire in the Sierra Nevada resulted in a long-term (44 +yr) decrease (>50%, P < 0.05) in soil extracellular enzyme activities, basal microbial respiration (56-72%, P < 0.05), and organic carbon (>50%, P < 0.05) in the upper 5 cm compared to sites that had not been burned for at least 115 yr. However, nitrogen (N) processes were only affected in the most recent fire site (4 yr post-fire). Net nitrification increased by over 600% in the most recent fire site (P < 0.001), but returned to similar levels as the unburned control in the 13-yr site. Contrary to previous studies, we did not find a consistent effect of plant cover type on soil biogeochemical processes in mid-successional (10-50 yr) forest soils. Rather, the 44-yr reduction in soil organic carbon (C) quantity correlated positively with dampened C cycling processes. Our results show the drastic and long-term implication of ecologically novel, high-severity fire on soil biogeochemistry and underscore the need for long-term fire ecological experiments.
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Affiliation(s)
- Nicholas C Dove
- Environmental Systems Graduate Group, University of California, Merced, California, 95343, USA
| | - Hugh D Safford
- Department of Evolution and Ecology, University of California, Davis, California, 95616, USA
- USDA-Forest Service, Pacific Southwest Region, Vallejo, California, 94592, USA
| | | | - Becky L Estes
- USDA-Forest Service, Pacific Southwest Research Station, Redding, California, 96002, USA
| | - Stephen C Hart
- Department of Life & Environmental Sciences and Sierra Nevada Research Institute, University of California, Merced, California, 95343, USA
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Hessburg PF, Miller CL, Parks SA, Povak NA, Taylor AH, Higuera PE, Prichard SJ, North MP, Collins BM, Hurteau MD, Larson AJ, Allen CD, Stephens SL, Rivera-Huerta H, Stevens-Rumann CS, Daniels LD, Gedalof Z, Gray RW, Kane VR, Churchill DJ, Hagmann RK, Spies TA, Cansler CA, Belote RT, Veblen TT, Battaglia MA, Hoffman C, Skinner CN, Safford HD, Salter RB. Climate, Environment, and Disturbance History Govern Resilience of Western North American Forests. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00239] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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6
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Stephens SL, Collins BM, Fettig CJ, Finney MA, Hoffman CM, Knapp EE, North MP, Safford H, Wayman RB. Drought, Tree Mortality, and Wildfire in Forests Adapted to Frequent Fire. Bioscience 2018. [DOI: 10.1093/biosci/bix146] [Citation(s) in RCA: 206] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Scott L Stephens
- Department of Environmental Science, Policy, and Management at the University of California, in Berkeley
| | - Brandon M Collins
- Center for Fire Research and Outreach at the University of California, in Berkeley
| | - Christopher J Fettig
- US Department of Agriculture (USDA) Forest Service, Pacific Southwest Research Station, in Davis, California
| | - Mark A Finney
- USDA Forest Service, Rocky Mountain Research Station, in Missoula, Montana
| | - Chad M Hoffman
- Department of Forest and Range Stewardship at Colorado State University, in Fort Collins
| | - Eric E Knapp
- USDA Forest Service, Pacific Southwest Research Station, in Redding, California
| | - Malcolm P North
- US Department of Agriculture (USDA) Forest Service, Pacific Southwest Research Station, in Davis, California
| | - Hugh Safford
- Department of Environmental Science and Policy at the University of California, in Davis
- HS is also with the USDA Forest Service, Pacific Southwest Region, in Vallejo, California
| | - Rebecca B Wayman
- Department of Environmental Science and Policy at the University of California, in Davis
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7
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Levine CR, Cogbill CV, Collins BM, Larson AJ, Lutz JA, North MP, Restaino CM, Safford HD, Stephens SL, Battles JJ. Evaluating a new method for reconstructing forest conditions from General Land Office survey records. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2017; 27:1498-1513. [PMID: 28370925 DOI: 10.1002/eap.1543] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 01/10/2017] [Accepted: 02/22/2017] [Indexed: 06/07/2023]
Abstract
Historical forest conditions are often used to inform contemporary management goals because historical forests are considered to be resilient to ecological disturbances. The General Land Office (GLO) surveys of the late 19th and early 20th centuries provide regionally quasi-contiguous data sets of historical forests across much of the Western United States. Multiple methods exist for estimating tree density from point-based sampling such as the GLO surveys, including distance-based and area-based approaches. Area-based approaches have been applied in California mixed-conifer forests but their estimates have not been validated. To assess the accuracy and precision of plotless density estimators with potential for application to GLO data in this region, we imposed a GLO sampling scheme on six mapped forest stands of known densities (159-784 trees/ha) in the Sierra Nevada in California, USA, and Baja California Norte, Mexico. We compared three distance-based plotless density estimators (Cottam, Pollard, and Morisita) as well as two Voronoi area (VA) estimators, the Delincé and mean harmonic Voronoi density (MHVD), to the true densities. We simulated sampling schemes of increasing intensity to assess sampling error. The relative error (RE) of density estimates for the GLO sampling scheme ranged from 0.36 to 4.78. The least biased estimate of tree density in every stand was obtained with the Morisita estimator and the most biased was obtained with the MHVD estimator. The MHVD estimates of tree density were 1.2-3.8 times larger than the true densities and performed best in stands subject to fire exclusion for 100 yr. The Delincé approach obtained accurate estimates of density, implying that the Voronoi approach is theoretically sound but that its application in the MHVD was flawed. The misapplication was attributed to two causes: (1) the use of a crown scaling factor that does not correct for the number of trees sampled and (2) the persistent underestimate of the true VA due to a weak relationship between tree size and VA. The magnitude of differences between true densities and MHVD estimates suggest caution in using results based on the MHVD to inform management and restoration practices in the conifer forests of the American West.
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Affiliation(s)
- Carrie R Levine
- Department of Environmental Science, Policy, and Management, University of California, 130 Mulford Hall, Berkeley, California, 94720, USA
| | - Charles V Cogbill
- Harvard Forest, Harvard University, 324 North Main Street, Petersham, Massachusetts, 01366, USA
| | - Brandon M Collins
- University of California Center for Fire Research and Outreach, College of Natural Resources, University of California, Berkeley, California, 94720, 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, USA
| | - Malcolm P North
- USDA Forest Service, Pacific Southwest Research Station, 1731 Research Park Drive, Davis, California, 95618, USA
| | - Christina M Restaino
- Department of Environmental Science and Policy, 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, USA
| | - John J Battles
- Department of Environmental Science, Policy, and Management, University of California, 130 Mulford Hall, Berkeley, California, 94720, USA
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8
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Stephens SL, Miller JD, Collins BM, North MP, Keane JJ, Roberts SL. Wildfire impacts on California spotted owl nesting habitat in the Sierra Nevada. Ecosphere 2016. [DOI: 10.1002/ecs2.1478] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Scott L. Stephens
- Division of Ecosystem Science Department of Environmental Science, Policy, and Management University of California 130 Mulford Hall Berkeley California 94720 USA
| | - Jay D. Miller
- USDA Forest Service Pacific Southwest Region, Fire and Aviation Management McClellan California 95652 USA
| | - Brandon M. Collins
- Pacific Southwest Research Station USDA Forest Service Davis California 95618 USA
- Center for Fire Research and Outreach University of California Berkeley California 94720 USA
| | - Malcolm P. North
- Pacific Southwest Research Station USDA Forest Service Davis California 95618 USA
| | - John J. Keane
- Pacific Southwest Research Station USDA Forest Service Davis California 95618 USA
| | - Susan L. Roberts
- University of California, Merced, Sierra Nevada Research Station 7799 Chilnualna Falls Road Wawona California 95389 USA
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9
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Stephens SL, Collins BM, Biber E, Fulé PZ. U.S.
federal fire and forest policy: emphasizing resilience in dry forests. Ecosphere 2016. [DOI: 10.1002/ecs2.1584] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Scott L. Stephens
- Division of Ecosystem ScienceDepartment of Environmental Science, Policy, and ManagementUniversity of California 130 Mulford Hall Berkeley California 94720 USA
| | - Brandon M. Collins
- Center for Fire Research and OutreachUniversity of California Berkeley California 94720 USA
| | - Eric Biber
- University of California, BerkeleySchool of Law 436 North Addition Berkeley California 94720 USA
| | - Peter Z. Fulé
- School of ForestryCollege of Engineering, Forestry, and Natural SciencesNorthern Arizona University Flagstaff Arizona 86011 USA
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10
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Stevens JT, Safford HD, North MP, Fried JS, Gray AN, Brown PM, Dolanc CR, Dobrowski SZ, Falk DA, Farris CA, Franklin JF, Fulé PZ, Hagmann RK, Knapp EE, Miller JD, Smith DF, Swetnam TW, Taylor AH. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America. PLoS One 2016; 11:e0147688. [PMID: 27196621 PMCID: PMC4873010 DOI: 10.1371/journal.pone.0147688] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 12/20/2015] [Indexed: 11/30/2022] Open
Abstract
Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the “stand age” variable from the US Forest Service Forest Inventory and Analysis (FIA) program reflects the timing of historical high-severity (i.e. stand-replacing) fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1) the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2) recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical “mixed-severity” fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.
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Affiliation(s)
- Jens T. Stevens
- John Muir Institute of the Environment, University of California, Davis, CA, 95616, United States of America
- * E-mail:
| | - Hugh D. Safford
- USDA Forest Service, Pacific Southwest Region, Vallejo, CA, 94592, United States of America
- Department of Environmental Science and Policy, University of California, Davis, CA, 95616, United States of America
| | - Malcolm P. North
- John Muir Institute of the Environment, University of California, Davis, CA, 95616, United States of America
- USDA Forest Service, Pacific Southwest Research Station, Davis, CA, 95616, United States of America
| | - Jeremy S. Fried
- USDA Forest Service, Forest Inventory and Analysis Program, Pacific Northwest Research Station, Portland, OR, 97205, United States of America
| | - Andrew N. Gray
- USDA Forest Service, Forest Inventory and Analysis Program, Pacific Northwest Research Station, Corvallis, OR, 97331, United States of America
| | - Peter M. Brown
- Rocky Mountain Tree-Ring Research, Fort Collins, CO, 80526, United States of America
| | - Christopher R. Dolanc
- Biology Department, Mercyhurst University, Erie, PA, 16546, United States of America
| | - Solomon Z. Dobrowski
- Dept. Forest Management, University of Montana, Missoula, MT, 59812, United States of America
| | - Donald A. Falk
- School of Natural Resources and the Environment, University of Arizona, Tucson, AZ, 85721, United States of America
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, 85721, United States of America
| | - Calvin A. Farris
- National Park Service, Pacific West Region, Fire and Aviation Management, Klamath Falls, OR, 97601, United States of America
| | - Jerry F. Franklin
- School of Environmental and Forest Sciences, University of Washington, Seattle, WA, 98195, United States of America
| | - Peter Z. Fulé
- School of Forestry, Northern Arizona University, Flagstaff, AZ, 86011, United States of America
| | - R. Keala Hagmann
- School of Environmental and Forest Sciences, University of Washington, Seattle, WA, 98195, United States of America
| | - Eric E. Knapp
- USDA Forest Service, Pacific Southwest Research Station, Redding, CA, 96002, United States of America
| | - Jay D. Miller
- USDA Forest Service, Pacific Southwest Region, Fire and Aviation Management, McClellan, CA, 95652, United States of America
| | - Douglas F. Smith
- Yosemite National Park, Yosemite, CA, 95389, United States of America
| | - Thomas W. Swetnam
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, 85721, United States of America
| | - Alan H. Taylor
- Department of Geography and Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA, 16802, United States of America
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11
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Parks SA, Miller C, Parisien MA, Holsinger LM, Dobrowski SZ, Abatzoglou J. Wildland fire deficit and surplus in the western United States, 1984–2012. Ecosphere 2015. [DOI: 10.1890/es15-00294.1] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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12
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Schneider EE, Sánchez Meador AJ, Covington WW. Reference conditions and historical changes in an unharvested ponderosa pine stand on sedimentary soil. Restor Ecol 2015. [DOI: 10.1111/rec.12296] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Eryn E. Schneider
- School of Forestry; Northern Arizona University; Box 15018 Flagstaff AZ 86011 U.S.A
- Present address: College of Forestry and Conservation, University of Montana; 32 Campus Drive Missoula MT 59812 U.S.A
| | - Andrew J. Sánchez Meador
- Ecological Restoration Institute, School of Forestry; Northern Arizona University; Box 15018 Flagstaff AZ 86011 U.S.A
| | - William W. Covington
- Ecological Restoration Institute, School of Forestry; Northern Arizona University; Box 15018 Flagstaff AZ 86011 U.S.A
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Stephens SL, Lydersen JM, Collins BM, Fry DL, Meyer MD. Historical and current landscape-scale ponderosa pine and mixed conifer forest structure in the Southern Sierra Nevada. Ecosphere 2015. [DOI: 10.1890/es14-00379.1] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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14
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Fire acting as an increasing spatial autocorrelation force: Implications for pattern formation and ecological facilitation. ECOLOGICAL COMPLEXITY 2015. [DOI: 10.1016/j.ecocom.2014.12.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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