DOI: 10.5061/dryad.qz612jmb7
title: Data from: A changing climate is snuffing out post-fire recovery in montane forests

description: Aim: Climate warming is increasing fire activity in many of Earth’s
 forested ecosystems. Because fire is an important catalyst for change,
 investigation of post-fire vegetation response is crucial for
 understanding the potential for future conversions from forest to
 non-forest vegetation types. To better understand effects of wildfire and
 climate warming on forest recovery, we assessed the extent to which
 climate and terrain influence spatiotemporal variation in past and future
 post-fire tree regeneration. Location: Montane forests, Rocky Mountains,
 USA Time Period: 1981-2099 Taxa Studied: Pinus ponderosa; Pseudotsuga
 menziesii Methods: We developed a network of dendrochronological samples
 (n = 717) and field plots (n = 1301) from post-fire environments spanning
 a range of topographic and climatic settings. We then used boosted
 regression trees to predict annual suitability for post-fire seedling
 establishment and generalized linear mixed models to predict total
 post-fire seedling abundances, reconstructing recent trends in post-fire
 recovery and projecting future dynamics using three general circulation
 models (GCMs) under moderate and extreme emission scenarios. Results:
 Though 1981-2015 declines in growing season (April-September)
 precipitation were associated with declining suitability for seedling
 establishment, 2021-2099 trends in precipitation were widely variable
 among GCMs, leading to mixed projections of future establishment
 suitability. In contrast, climatic water deficit (CWD), strongly tied to
 warming temperature and increased evaporative demand, was projected to
 increase throughout our study area. Our projections strongly suggest that
 future increases in CWD and an increased frequency of extreme drought will
 reduce post-fire seedling abundances. Main Conclusions: Our findings
 highlight the key roles of warming and drying in declines in forest
 resilience to wildfire. The striking differences in projections of
 post-fire recovery between moderate and extreme emissions scenarios
 suggest that the most extreme impacts on forest resilience in the latter
 part of the 21st century may be mitigated with aggressive emissions
 reductions in the next two decades.
description: This archive includes field data and various spatial datasets
 used in Rodman et al. (2020; Global Ecology and Biogeography).
 Individual datasets in the Dryad archive include the
 following: 1) Gridded climate data (annual actual
 evapotranspiration, annual climatic water deficit, growing season
 precipitation) for the 1981-2015 period and future climate projections
 (2021-2099). All climate data were spatially downscaled to c. 250
 m. 2) Statistical models and outputs (.rds objects,
 example spatial models, and summaries of statistical outputs)
 3) Terrain variables (60-m resolution) of topographic position
 index and heat load index. Soil available water capacity at a
 4km-resolution. 4) Shapefiles of fire perimeters
 included in the study and the boundary of the study area (i.e., EPA Level
 III Ecoregion #21) 5) Field data summarized in this
 study including 1) 1301 individual field plots characterizing post-fire
 conifer seedling abundance, forest structure, and ground cover and 2) 717
 destructively sampled seedlings dated to establishment/germination
 year. These data are a synthesis of five previously
 published studies that surveyed post-fire seedling abundance and the
 timing of seedling establishment, as well as previously unpublished data
 following the study design of Chambers et al. (2016). As methods of
 collection vary slightly among individual studies, we refer the user to
 the original published studies (listed below). See "README.txt"
 for a description of the processing and development of new datasets (i.e.,
 gridded climate data, terrain variables, spatial models, and statistical
 models). Chambers, M. E., P. J. Fornwalt, S. L. Malone,
 and M. A. Battaglia. 2016. Patterns of Conifer Regeneration Following High
 Severity Wildfire in Ponderosa Pine ñ Dominated Forests of the Colorado
 Front Range. Forest Ecology and Management 378:57ñ67.
 Ouzts, J. R., Kolb, T. E., Huffman, D. W., and A. J. Sánchez
 Meador. 2015. Post-fire Ponderosa Pine Regeneration With and Without
 Planting in Arizona and New Mexico. Forest Ecology and Management
 354:281ñ290. Rother, M. T., and T. T. Veblen. 2016.
 Limited Conifer Regeneration Following Wildfires in Dry Ponderosa Pine
 Forests of the Colorado Front Range. Ecosphere 7:e01594.
 Rother, M. T., and T. T. Veblen. 2017. Climate Drives Episodic
 Conifer Establishment after Fire in Dry Ponderosa Pine Forests of the
 Colorado. Forests 8:1-14. Rodman, K. C., Veblen, T. T.,
 Chapman, T. B., Rother, M. T., Wion, A. P., and M. D. Redmond. 2020b.
 Limitations to Recovery Following Wildfire in Dry Forests of Southern
 Colorado and Northern New Mexico, USA. Ecological Applications
 30:e02001.
description: See "README.txt" and metadata within the compressed
 archive files for usage notes. We encourage the user to contact