Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapes
Abstract Altered fire regimes can drive major and enduring compositional shifts or losses of forest ecosystems. In western North America, ponderosa pine and dry mixed‐conifer forest types appear increasingly vulnerable to uncharacteristically extensive, high‐severity wildfire. However, unburned or o...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2019-07-01
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| Series: | Ecosphere |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ecs2.2809 |
| _version_ | 1818911730643763200 |
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| author | Jonathan D. Coop Timothy J. DeLory William M. Downing Sandra L. Haire Meg A. Krawchuk Carol Miller Marc‐André Parisien Ryan B. Walker |
| author_facet | Jonathan D. Coop Timothy J. DeLory William M. Downing Sandra L. Haire Meg A. Krawchuk Carol Miller Marc‐André Parisien Ryan B. Walker |
| author_sort | Jonathan D. Coop |
| collection | DOAJ |
| description | Abstract Altered fire regimes can drive major and enduring compositional shifts or losses of forest ecosystems. In western North America, ponderosa pine and dry mixed‐conifer forest types appear increasingly vulnerable to uncharacteristically extensive, high‐severity wildfire. However, unburned or only lightly impacted forest stands that persist within burn mosaics—termed fire refugia—may serve as tree seed sources and promote landscape recovery. We sampled tree regeneration along gradients of fire refugia proximity and density at 686 sites within the perimeters of 12 large wildfires that occurred between 2000 and 2005 in the interior western United States. We used generalized linear mixed‐effects models to elucidate statistical relationships between tree regeneration and refugia pattern, including a new metric that incorporates patch proximity and proportional abundance. These relationships were then used to develop a spatially explicit landscape simulation model. We found that regeneration by ponderosa pine and obligate‐seeding mixed‐conifer tree species assemblages was strongly and positively predicted by refugia proximity and density. Simulation models revealed that for any given proportion of the landscape occupied by refugia, small patches produced greater landscape recovery than large patches. These results highlight the disproportionate importance of small, isolated islands of surviving trees, which may not be detectable with coarse‐scale satellite imagery. Findings also illustrate the interplay between patch‐scale resistance and landscape‐scale resilience: Disturbance‐resistant settings (fire refugia) can entrain resilience (forest regeneration) across the burn matrix. Implications and applications for land managers and conservation practitioners include strategies for the promotion and maintenance of fire refugia as components of resilient forest landscapes. |
| first_indexed | 2024-12-19T23:03:21Z |
| format | Article |
| id | doaj.art-b11bf350ce204510986ba9d4a9823927 |
| institution | Directory Open Access Journal |
| issn | 2150-8925 |
| language | English |
| last_indexed | 2024-12-19T23:03:21Z |
| publishDate | 2019-07-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecosphere |
| spelling | doaj.art-b11bf350ce204510986ba9d4a98239272022-12-21T20:02:27ZengWileyEcosphere2150-89252019-07-01107n/an/a10.1002/ecs2.2809Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapesJonathan D. Coop0Timothy J. DeLory1William M. Downing2Sandra L. Haire3Meg A. Krawchuk4Carol Miller5Marc‐André Parisien6Ryan B. Walker7School of Environment and Sustainability Western Colorado University Gunnison Colorado 81231 USADepartment of Biology Utah State University Logan Utah 84322 USADepartment of Forest Ecosystems and Society Oregon State University Corvallis Oregon 97331 USAHaire Laboratory for Landscape Ecology Belfast Maine 04915 USADepartment of Forest Ecosystems and Society Oregon State University Corvallis Oregon 97331 USAAldo Leopold Wilderness Research Institute Rocky Mountain Research Station USDA Forest Service Missoula Montana 59801 USANorthern Forestry Centre Canadian Forest Service Natural Resources Canada Edmonton Alberta CanadaSchool of Environment and Sustainability Western Colorado University Gunnison Colorado 81231 USAAbstract Altered fire regimes can drive major and enduring compositional shifts or losses of forest ecosystems. In western North America, ponderosa pine and dry mixed‐conifer forest types appear increasingly vulnerable to uncharacteristically extensive, high‐severity wildfire. However, unburned or only lightly impacted forest stands that persist within burn mosaics—termed fire refugia—may serve as tree seed sources and promote landscape recovery. We sampled tree regeneration along gradients of fire refugia proximity and density at 686 sites within the perimeters of 12 large wildfires that occurred between 2000 and 2005 in the interior western United States. We used generalized linear mixed‐effects models to elucidate statistical relationships between tree regeneration and refugia pattern, including a new metric that incorporates patch proximity and proportional abundance. These relationships were then used to develop a spatially explicit landscape simulation model. We found that regeneration by ponderosa pine and obligate‐seeding mixed‐conifer tree species assemblages was strongly and positively predicted by refugia proximity and density. Simulation models revealed that for any given proportion of the landscape occupied by refugia, small patches produced greater landscape recovery than large patches. These results highlight the disproportionate importance of small, isolated islands of surviving trees, which may not be detectable with coarse‐scale satellite imagery. Findings also illustrate the interplay between patch‐scale resistance and landscape‐scale resilience: Disturbance‐resistant settings (fire refugia) can entrain resilience (forest regeneration) across the burn matrix. Implications and applications for land managers and conservation practitioners include strategies for the promotion and maintenance of fire refugia as components of resilient forest landscapes.https://doi.org/10.1002/ecs2.2809burn severitydispersalfire refugelandscape memorylandscape simulation modelsrefugia |
| spellingShingle | Jonathan D. Coop Timothy J. DeLory William M. Downing Sandra L. Haire Meg A. Krawchuk Carol Miller Marc‐André Parisien Ryan B. Walker Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapes Ecosphere burn severity dispersal fire refuge landscape memory landscape simulation models refugia |
| title | Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapes |
| title_full | Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapes |
| title_fullStr | Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapes |
| title_full_unstemmed | Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapes |
| title_short | Contributions of fire refugia to resilient ponderosa pine and dry mixed‐conifer forest landscapes |
| title_sort | contributions of fire refugia to resilient ponderosa pine and dry mixed conifer forest landscapes |
| topic | burn severity dispersal fire refuge landscape memory landscape simulation models refugia |
| url | https://doi.org/10.1002/ecs2.2809 |
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