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  1. Article ; Online: Predictive accuracy of post‐fire conifer death declines over time in models based on crown and bole injury

    Shearman, Timothy M. / Varner, J. Morgan / Hood, Sharon M. / van Mantgem, Phillip J. / Cansler, C. Alina / Wright, Micah

    Ecological Applications. 2023 Mar., v. 33, no. 2 p.e2760-

    2023  

    Abstract: A key uncertainty of empirical models of post‐fire tree mortality is understanding the drivers of elevated post‐fire mortality several years following fire, known as delayed mortality. Delayed mortality can represent a substantial fraction of mortality, ... ...

    Abstract A key uncertainty of empirical models of post‐fire tree mortality is understanding the drivers of elevated post‐fire mortality several years following fire, known as delayed mortality. Delayed mortality can represent a substantial fraction of mortality, particularly for large trees that are a conservation focus in western US coniferous forests. Current post‐fire tree mortality models have undergone limited evaluation of how injury level and time since fire interact to influence model accuracy and predictor variable importance. Less severe injuries potentially serve as an indicator for vulnerability to additional stressors such as bark beetle attack or moisture stress. We used a collection of 164,293 individual tree records to examine post‐fire tree mortality in eight western USA conifers: Abies concolor, Abies grandis, Calocedrus decurrens, Larix occidentalis, Pinus contorta, Pinus lambertiana, Pinus ponderosa, and Pseudotsuga menziesii. We evaluated the importance of fire injury predictors on discriminating between surviving trees versus immediate and delayed post‐fire mortality. We fit balanced random forest models for each species using cumulative tree mortality from 1 to 5‐years post‐fire. We compared these results to multi‐class random forest models using first‐year mortality, 2–5‐year mortality, and survival 5‐years post‐fire as a response variable. Crown volume scorched, diameter at breast height, and relative bark char height, were used as predictor variables. The cumulative mortality models all predicted trees that died within 1‐year of fire with high accuracy but failed to predict 2–5‐year mortality. The multi‐class models were an improvement but had lower accuracy for predicting 2–5‐year mortality. Multi‐class model accuracies ranged from 85% to 95% across all species for predicting 1‐year post‐fire mortality, 42%–71% for predicting 2–5‐year mortality, and 64%–85% for predicting trees that lived past 5‐years. Our study highlights the differences in tree species tolerance to fire injury and suggests that including second‐order predictors such as beetle attack or climatic water stress before and after fire will be critical to improve accuracy and better understand the mechanisms and patterns of fire‐caused tree death. Random forest models have potential for management applications such as post‐fire harvesting and simulating future stand dynamics.
    Keywords Abies concolor ; Abies grandis ; Calocedrus decurrens ; Coleoptera ; Larix occidentalis ; Pinus contorta ; Pinus lambertiana ; Pinus ponderosa ; Pseudotsuga menziesii ; bark ; bark beetles ; conifers ; death ; mortality ; tree and stand measurements ; tree mortality ; tree trunk ; trees ; uncertainty ; water stress ; Western United States
    Language English
    Dates of publication 2023-03
    Publishing place John Wiley & Sons, Inc.
    Document type Article ; Online
    Note JOURNAL ARTICLE
    ZDB-ID 1074505-1
    ISSN 1939-5582 ; 1051-0761
    ISSN (online) 1939-5582
    ISSN 1051-0761
    DOI 10.1002/eap.2760
    Database NAL-Catalogue (AGRICOLA)

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  2. Article: Predictive accuracy of post-fire conifer death declines over time in models based on crown and bole injury.

    Shearman, Timothy M / Varner, J Morgan / Hood, Sharon M / van Mantgem, Phillip J / Cansler, C Alina / Wright, Micah

    Ecological applications : a publication of the Ecological Society of America

    2022  Volume 33, Issue 2, Page(s) e2760

    Abstract: A key uncertainty of empirical models of post-fire tree mortality is understanding the drivers of elevated post-fire mortality several years following fire, known as delayed mortality. Delayed mortality can represent a substantial fraction of mortality, ... ...

    Abstract A key uncertainty of empirical models of post-fire tree mortality is understanding the drivers of elevated post-fire mortality several years following fire, known as delayed mortality. Delayed mortality can represent a substantial fraction of mortality, particularly for large trees that are a conservation focus in western US coniferous forests. Current post-fire tree mortality models have undergone limited evaluation of how injury level and time since fire interact to influence model accuracy and predictor variable importance. Less severe injuries potentially serve as an indicator for vulnerability to additional stressors such as bark beetle attack or moisture stress. We used a collection of 164,293 individual tree records to examine post-fire tree mortality in eight western USA conifers: Abies concolor, Abies grandis, Calocedrus decurrens, Larix occidentalis, Pinus contorta, Pinus lambertiana, Pinus ponderosa, and Pseudotsuga menziesii. We evaluated the importance of fire injury predictors on discriminating between surviving trees versus immediate and delayed post-fire mortality. We fit balanced random forest models for each species using cumulative tree mortality from 1 to 5-years post-fire. We compared these results to multi-class random forest models using first-year mortality, 2-5-year mortality, and survival 5-years post-fire as a response variable. Crown volume scorched, diameter at breast height, and relative bark char height, were used as predictor variables. The cumulative mortality models all predicted trees that died within 1-year of fire with high accuracy but failed to predict 2-5-year mortality. The multi-class models were an improvement but had lower accuracy for predicting 2-5-year mortality. Multi-class model accuracies ranged from 85% to 95% across all species for predicting 1-year post-fire mortality, 42%-71% for predicting 2-5-year mortality, and 64%-85% for predicting trees that lived past 5-years. Our study highlights the differences in tree species tolerance to fire injury and suggests that including second-order predictors such as beetle attack or climatic water stress before and after fire will be critical to improve accuracy and better understand the mechanisms and patterns of fire-caused tree death. Random forest models have potential for management applications such as post-fire harvesting and simulating future stand dynamics.
    MeSH term(s) Animals ; Pinus ; Pinus ponderosa/physiology ; Fires ; Coleoptera/physiology ; Pseudotsuga/physiology
    Language English
    Publishing date 2022-12-08
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 1074505-1
    ISSN 1939-5582 ; 1051-0761
    ISSN (online) 1939-5582
    ISSN 1051-0761
    DOI 10.1002/eap.2760
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Post-fire landscape evaluations in Eastern Washington, USA: Assessing the work of contemporary wildfires

    Churchill, Derek J. / Jeronimo, Sean M.A. / Hessburg, Paul F. / Cansler, C. Alina / Povak, Nicholas A. / Kane, Van R. / Lutz, James A. / Larson, Andrew J.

    Forest ecology and management. 2022 Jan. 15, v. 504

    2022  

    Abstract: In the western US, wildfires are modifying the structure, composition, and patterns of forested landscapes at rates that far exceed mechanical thinning and prescribed fire treatments. There are conflicting narratives as to whether these wildfires are ... ...

    Abstract In the western US, wildfires are modifying the structure, composition, and patterns of forested landscapes at rates that far exceed mechanical thinning and prescribed fire treatments. There are conflicting narratives as to whether these wildfires are restoring landscape resilience to future climate and wildfires. To evaluate the landscape-level work of wildfires, we assessed four subwatersheds in eastern Washington, USA that experienced large wildfires in 2014, 2015, or 2017 after more than a century of fire exclusion and extensive timber harvest. We compared pre- and post-fire landscape conditions to an ecoregion-specific historical (HRV) and future range of variation (FRV) based on empirically established reference conditions derived from a large dataset of historical aerial photo imagery. These four wildfires proved to be a blunt restoration tool, moving some attributes towards more climate-adapted conditions and setting others back. Fires reduced canopy cover and decreased overall tree size and canopy complexity, which moved them into, or slightly outside, the FRV ranges. Moderate- and low-severity fire generally shifted closed-canopy forest structure to open-canopy classes. Patches of high-severity fire shifted patterns of forest, woodland, grassland, and shrubland towards or beyond the HRV ranges and within the FRV ranges by increasing the total area and size of non-forest patches. However, large patches of high-severity fire in dry and moist mixed-conifer forests homogenized landscape patterns beyond FRV ranges towards simplified conditions dominated by non-forest vegetation types. Fires realigned and reconnected landscape patterns with the topo-edaphic template in some cases, but pre-existing fragmentation and spatial mismatches were compounded in many others. Patches of large-tree, closed-canopy forest were reduced by high-severity fire, and the potential to restore more climate-adapted large-tree, open-canopy forest was lost. Re-establishing landscape patterns with desired patch sizes of forest, in particular patches with large trees, will take many decades to centuries and may not occur in drier locations or where seed trees are no longer present. While large wildfires burning during extreme fire weather conditions can move some attributes towards HRV and FRV ranges, intentionally planned mechanical and prescribed-fire treatments that are integrated with strategic wildfire response will better prepare and adapt landscapes for future wildfires and climate.
    Keywords administrative management ; aerial photography ; canopy ; climate ; data collection ; fire weather ; forest ecology ; forests ; grasslands ; landscapes ; prescribed burning ; shrublands ; subwatersheds ; wildfires ; woodlands
    Language English
    Dates of publication 2022-0115
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 751138-3
    ISSN 0378-1127
    ISSN 0378-1127
    DOI 10.1016/j.foreco.2021.119796
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: Tamm Review: Ecological principles to guide post-fire forest landscape management in the Inland Pacific and Northern Rocky Mountain regions

    Larson, Andrew J. / Jeronimo, Sean M.A. / Hessburg, Paul F. / Lutz, James A. / Povak, Nicholas A. / Cansler, C. Alina / Kane, Van R. / Churchill, Derek J.

    Elsevier B.V. Forest ecology and management. 2022 Jan. 15, v. 504

    2022  

    Abstract: Post-fire landscapes are the frontline of forest ecosystem change. As such, they represent opportunities to foster conditions that are better adapted to future climate and wildfires with post-fire management. In western US landscapes, post-fire ... ...

    Abstract Post-fire landscapes are the frontline of forest ecosystem change. As such, they represent opportunities to foster conditions that are better adapted to future climate and wildfires with post-fire management. In western US landscapes, post-fire management has been mostly defined by short-term emergency mitigation measures, salvage harvest to recover economic value, and replanting to achieve full stocking.These approaches are largely incongruent with ecologically based forest management due to their limited scope and objectives. Here, we develop a framework for ecologically based post-fire management. Post-fire management principles are to (i) protect large-diameter trees and fire refugia; (ii) anticipate future fuel accumulation from post-fire tree mortality; (iii) reinitiate and maintain stabilizing fire-vegetation feedbacks; (iv) differentiate between climate- and dispersal-mediated transitions to non-forest; and (v) align species composition and structure with future fire regimes and climate. Stand-scale management strategies to implement these principles include (i) maintain or enhance forest resilience; (ii) restore forest conditions and resist transition to non-forest; and (iii) accept or facilitate transition to non-forest. Determining where and over what extent to deploy these stand-scale strategies in large, burned landscapes is informed by a post-fire landscape evaluation, and expressed with a landscape prescription. A post-fire landscape evaluation is a data-driven characterization of current vegetation conditions, including the immediate changes caused by wildfire, and includes a departure analysis—an evaluation of current conditions against reference conditions. The landscape prescription provides guidance about the distribution of different successional patches and their sizes across the topographic template and identifies priority areas for different post-fire treatments. We develop a geospatial framework to integrate ecological principles with a post-fire landscape evaluation that can be readily applied to management planning after wildfire. We illustrate application of these principles through the development of landscape prescriptions for two watersheds, each burned in a recent large fire, in northeast Washington, USA. Use of ecologically based post-fire management principles and landscape evaluations can help shift often contentious debates over salvage harvesting towards a more productive dialogue around how to best adapt landscapes to future conditions.
    Keywords climate ; economic valuation ; forest ecosystems ; forest management ; forests ; landscape management ; landscapes ; refuge habitats ; species diversity ; tree mortality ; wildfires
    Language English
    Dates of publication 2022-0115
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 751138-3
    ISSN 0378-1127
    ISSN 0378-1127
    DOI 10.1016/j.foreco.2021.119680
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: Sierra Nevada reference conditions: A dataset of contemporary reference sites and corresponding remote sensing-derived forest structure metrics for yellow pine and mixed-conifer forests.

    Chamberlain, Caden P / Cova, Gina R / Kane, Van R / Cansler, C Alina / Kane, Jonathan T / Bartl-Geller, Bryce N / van Wagtendonk, Liz / Jeronimo, Sean M A / Stine, Peter / North, Malcolm P

    Data in brief

    2023  Volume 51, Page(s) 109807

    Abstract: Contemporary reference sites in California's Sierra Nevada represent areas where a frequent, low-intensity fire regime - an integral ecological process in temperate dry forests - has been reintroduced after several decades of fire suppression. Produced ... ...

    Abstract Contemporary reference sites in California's Sierra Nevada represent areas where a frequent, low-intensity fire regime - an integral ecological process in temperate dry forests - has been reintroduced after several decades of fire suppression. Produced by an intact fire regime, forest structural patterns in these sites are likely more resilient to future disturbances and climate, and thus can provide reference conditions to guide management and ecological research. In this paper, we present a set of 119 delineated contemporary reference sites in the Sierra Nevada yellow pine and mixed-conifer zone along with a suite of key remote sensing-derived forest structure metrics representing conditions within these sites. We also provide a set of summary figures for individual reference sites and sites grouped by dominant climate class. We identified restored frequent-fire landscapes using a combination of fire history, burn severity, management history, and forest type datasets and we delineated individual polygons using catchment basins, fire perimeters, and imagery. Reference sites ranged in size from 101-966 ha with a mean size of 240 ha. Where available (for 59 sites), we used airborne lidar datasets to characterize a suite of key forest structure metrics within reference sites. Across all 119 sites, we provide a set of forest structure metrics produced by the California Forest Observatory. Reference sites were categorized based on their dominant climate class to assist users in identifying the most climatically relevant reference conditions for their project or study area. We encourage the use of the reference sites and associated forest structure datasets for guiding ecologically focused forest management and research in the Sierra Nevada.
    Language English
    Publishing date 2023-11-14
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 2786545-9
    ISSN 2352-3409 ; 2352-3409
    ISSN (online) 2352-3409
    ISSN 2352-3409
    DOI 10.1016/j.dib.2023.109807
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Determination of burn severity models ranging from regional to national scales for the conterminous United States

    Picotte, Joshua J. / Cansler, C. Alina / Kolden, Crystal A. / Lutz, James A. / Key, Carl / Benson, Nathan C. / Robertson, Kevin M.

    Elsevier Inc. Remote sensing of environment. 2021 Sept. 15, v. 263

    2021  

    Abstract: Identifying meaningful measures of ecological change over large areas is dependent on the quantification of robust relationships between ecological metrics and remote sensing products. Over the past several decades, ground observations of wildfire and ... ...

    Abstract Identifying meaningful measures of ecological change over large areas is dependent on the quantification of robust relationships between ecological metrics and remote sensing products. Over the past several decades, ground observations of wildfire and prescribed fire severity have been acquired across hundreds of wildland fires in the United States, primarily utilizing the Composite Burn Index (CBI) plot protocol. These observations have been coupled to spaceborne passive spectral reflectance indices (e.g. Landsat-derived variations of the Normalized Burn Ratio [NBR]) to produce regression models describing their relationship. Here we develop regression models by vegetation type for multiple vegetation classification systems representing a range of spatial scales, and a decision tree framework for evaluating these regression models. Our overall goals were to determine which scale of ecological classifications provided the best estimate of burn severity from Landsat data and how to choose the best regression model. We aggregated a total of 6280 CBI plots for 234 wildland fires that burned between 1994 and 2017 and produced Landsat-derived NBR and differenced NBR (dNBR) values for each plot. We then calculated best fit linear or higher order regression equations between CBI and NBR/dNBR for each landcover classification system from smallest to largest scale: LANDFIRE Biophysical Settings (BPS), National Vegetation Classification macrogroup (NVC) landcover classifications, Omernick III, II, and I ecoregions, LANDFIRE Fire Regime Groups (FRG), and the entire conterminous United States (CONUS) dataset. The CONUS regression model goodness of fit was moderate (R² = 0.55, P < 0.001) for dNBR and poor (R² = 0.30, P < 0.001) for NBR. Within landcover classifications, CBI was better fit by dNBR than NBR. Finer scale regional regression models including BPS (dNBR R2¯ = 0.56 and 0.00–0.83 R² range; NBR R2¯ = 0.43 and 0.00–0.82 R² range) and NVC (dNBR R2¯ = 0.55 and 0.15–0.78 R² range; NBR R2¯ = 0.41 and 0.00–0.79 R² range) were on average the same or better than the CONUS models for dNBR and NBR, with the strongest fit models exhibiting R² ≥ 0.70, whereas larger scale regional models R2¯ ranged from 0.28 to 0.5. However, variation in accuracy among landcover types indicate that dNBR and NBR regression models could be used to effectively estimate CBI for future fires in certain regions, while for other regions models may require additional field observations or alternative spectral transformations. Our decision tree schema can be used to help users determine which scale is likely to produce the most accurate results using our models. The CBI regression models developed here, paired with the decision tree, provide users with a simple method to estimate burn severity in units of CBI for any fire within CONUS with moderate to high levels of confidence and provide a template for further development of models with new data going forward.
    Keywords Landsat ; burn severity ; data collection ; decision support systems ; environment ; fire regime ; fire severity ; land cover ; prescribed burning ; reflectance ; regression analysis ; vegetation types ; wildfires ; wildland
    Language English
    Dates of publication 2021-0915
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 431483-9
    ISSN 0034-4257
    ISSN 0034-4257
    DOI 10.1016/j.rse.2021.112569
    Database NAL-Catalogue (AGRICOLA)

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  7. Article: Previous wildfires and management treatments moderate subsequent fire severity

    Cansler, C. Alina / Kane, Van R. / Hessburg, Paul F. / Kane, Jonathan T. / Jeronimo, Sean M.A. / Lutz, James A. / Povak, Nicholas A. / Churchill, Derek J. / Larson, Andrew J.

    Elsevier B.V. Forest ecology and management. 2022 Jan. 15, v. 504

    2022  

    Abstract: We investigated the relative importance of daily fire weather, landscape position, climate, recent forest and fuels management, and fire history to explaining patterns of remotely-sensed burn severity – as measured by the Relativized Burn Ratio – in 150 ... ...

    Abstract We investigated the relative importance of daily fire weather, landscape position, climate, recent forest and fuels management, and fire history to explaining patterns of remotely-sensed burn severity – as measured by the Relativized Burn Ratio – in 150 fires occurring from 2001 to 2019, which burned conifer forests of northeastern Washington State, USA. Daily fire weather, annual precipitation anomalies, and species’ fire resistance traits were important predictors of wildfire burn severity. In areas burned within the past two to three decades, prior fire decreased the severity of subsequent burns, particularly for the first 16 postfire years. In areas managed before a wildfire, thinning and prescribed burning treatments lowered burn severity relative to untreated controls. Prescribed burning was the most effective treatment at lowering subsequent burn severity, and prescribed burned areas were usually unburned or burned at low severity in subsequent wildfires. Patches that were harvested and planted <10 years before a wildfire burned with slightly higher severity. In areas managed within 5 years after an initial fire, postfire harvest and planting reduced prevalence of stand-replacing fire in reburns. However, overall, postfire management actions after a first wildfire only weakly influenced the severity of subsequent fires. The importance of fire-fire interactions to moderating burn severity establishes the importance of stabilizing feedbacks in active fire regimes, and our results demonstrate how silvicultural treatments can be combined with prescribed fire and wildfires to maintain resilient landscapes.
    Keywords Washington (state) ; administrative management ; atmospheric precipitation ; burn severity ; climate ; conifers ; fire history ; fire resistance ; fire severity ; fire weather ; forest ecology ; landscape position ; prescribed burning ; remote sensing ; wildfires
    Language English
    Dates of publication 2022-0115
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 751138-3
    ISSN 0378-1127
    ISSN 0378-1127
    DOI 10.1016/j.foreco.2021.119764
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  8. Article: Postfire treatments alter forest canopy structure up to three decades after fire

    Cansler, C. Alina / Kane, Van R. / Bartl-Geller, Bryce N. / Churchill, Derek J. / Hessburg, Paul F. / Povak, Nicholas A. / Lutz, James A. / Kane, Jonathan / Larson, Andrew J.

    Elsevier B.V. Forest ecology and management. 2022 Feb. 01, v. 505

    2022  

    Abstract: We evaluated the effects of postfire management on forest structure in mixed-conifer forests of northeastern Washington, USA. Postfire treatments were harvest-only, harvest combined with planting, planting-only, and postfire prescribed fire. We used ... ...

    Abstract We evaluated the effects of postfire management on forest structure in mixed-conifer forests of northeastern Washington, USA. Postfire treatments were harvest-only, harvest combined with planting, planting-only, and postfire prescribed fire. We used aerial light detection and ranging (LiDAR) to measure vertical and horizontal components of postfire forest structure over a period of 2 to 32 years after fires. We compared treated areas to control areas with similar bioclimatic environments and past fire severity. We used niche overlap statistics to quantify distributions of individual forest structure components and PERMANOVA to assess forest structural response to the presence or absence of treatments, past fire severity, time since treatment, and bioclimatic setting. Harvest alone after fire decreased dominant tree height and reduced vertical canopy complexity and the cover of tall trees. Harvest combined with planting increased dominant tree height, vertical complexity, and cover in lower height strata. Planting and prescribed fires showed little difference in forest structure relative to untreated controls. Overall, the burn severity of the initial fire was the strongest influence on postfire structure, and many aspects of vertical and horizontal forest structure showed little difference with increasing time since fire.
    Keywords administrative management ; burn severity ; fire severity ; forest canopy ; forest ecology ; forests ; lidar ; planting ; prescribed burning ; statistics ; tree height
    Language English
    Dates of publication 2022-0201
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 751138-3
    ISSN 0378-1127
    ISSN 0378-1127
    DOI 10.1016/j.foreco.2021.119872
    Database NAL-Catalogue (AGRICOLA)

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  9. Article: Modelling post-fire tree mortality: Can random forest improve discrimination of imbalanced data?

    Shearman, Timothy M / Cansler, C. Alina / Hiers, J. Kevin / Hood, Sharon M / Varner, J. Morgan

    Elsevier B.V. Ecological modelling. 2019 Dec. 15, v. 414

    2019  

    Abstract: Predicting post-fire tree mortality is a major area of research in fire-prone forests, woodlands, and savannas worldwide. Past research has relied overwhelmingly on logistic regression analysis (LR) that predicts post-fire tree status as a binary outcome ...

    Abstract Predicting post-fire tree mortality is a major area of research in fire-prone forests, woodlands, and savannas worldwide. Past research has relied overwhelmingly on logistic regression analysis (LR) that predicts post-fire tree status as a binary outcome (i.e. living or dead). One of the most problematic issues for LR (or any classification problem) occurs when there is a class imbalance in the training data. In these instances, predictions will be biased toward the majority class. Using a historical prescribed fire data set of longleaf pines (Pinus palustris) from northern Florida, USA, we compare results from standard LR and the machine-learning algorithm, random forest (RF). First, we demonstrate the class imbalance problem using simulated data. We then show how a balanced RF model can be used to alleviate the bias in the model and improve mortality prediction results. In the simulated example, LR model sensitivity and specificity was clearly biased based on the degree of imbalance between the classes. The balanced RF models had consistent sensitivity and specificity throughout the simulated data sets. Re-analyzing the original longleaf pine data set with a balanced RF model showed that although both LR and RF models had similar areas under the receiver operating curve (AUC), the RF model had better discrimination for predicting new observations of dead trees. Both LR and RF models identified duff consumption and percent crown scorch as important predictors of tree mortality, however the RF model also suggested pre-fire duff depth as an important predictor. Our analysis highlights LR limitations when data are imbalanced and supports using RF to develop post-fire tree mortality models. We suggest how RF can be incorporated into future tree mortality studies, as well as possible implementation in future decision-support tools.
    Keywords algorithms ; data collection ; dead wood ; decision support systems ; forests ; models ; mortality ; Pinus palustris ; prediction ; prescribed burning ; regression analysis ; savannas ; scorch ; tree mortality ; trees ; woodlands ; Florida
    Language English
    Dates of publication 2019-1215
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 191971-4
    ISSN 0304-3800
    ISSN 0304-3800
    DOI 10.1016/j.ecolmodel.2019.108855
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  10. Article: Climate, fire size, and biophysical setting control fire severity and spatial pattern in the northern Cascade Range, USA.

    Cansler, C Alina / McKenzie, Donald

    Ecological applications : a publication of the Ecological Society of America

    2014  Volume 24, Issue 5, Page(s) 1037–1056

    Abstract: Warmer and drier climate over the past few decades has brought larger fire sizes and increased annual area burned in forested ecosystems of western North America, and continued increases in annual area burned are expected due to climate change. As ... ...

    Abstract Warmer and drier climate over the past few decades has brought larger fire sizes and increased annual area burned in forested ecosystems of western North America, and continued increases in annual area burned are expected due to climate change. As warming continues, fires may also increase in severity and produce larger contiguous patches of severely burned areas. We used remotely sensed burn-severity data from 125 fires in the northern Cascade Range of Washington, USA, to explore relationships between fire size, severity, and the spatial pattern of severity. We examined relationships between climate and the annual area burned and the size of wildfires over a 25-year period. We tested the hypothesis that increased fire size is commensurate with increased burn severity and increased spatial aggregation of severely burned areas. We also asked how local ecological controls might modulate these relationships by comparing results over the whole study area (the northern Cascade Range) to those from four ecological subsections within it. We found significant positive relationships between climate and fire size, and between fire size and the proportion of high severity and spatial-pattern metrics that quantify the spatial aggregation of high-severity areas within fires, but the strength and significance of these relationships varied among the four subsections. In areas with more contiguous subalpine forests and less complex topography, the proportion and spatial aggregation of severely burned areas were more strongly correlated with fire size. If fire sizes increase in a warming climate, changes in the extent, severity, and spatial pattern of fire regimes are likely to be more pronounced in higher-severity fire regimes with less complex topography and more continuous fuels.
    MeSH term(s) Climate ; Climate Change ; Ecosystem ; Fires ; North America ; Trees ; Washington
    Language English
    Publishing date 2014-08-25
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 1074505-1
    ISSN 1939-5582 ; 1051-0761
    ISSN (online) 1939-5582
    ISSN 1051-0761
    DOI 10.1890/13-1077.1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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