Dataset Information

Reduced fire severity offers near-term buffer to climate-driven declines in conifer resilience across the western United States.

ABSTRACT: Increasing fire severity and warmer, drier postfire conditions are making forests in the western United States (West) vulnerable to ecological transformation. Yet, the relative importance of and interactions between these drivers of forest change remain unresolved, particularly over upcoming decades. Here, we assess how the interactive impacts of changing climate and wildfire activity influenced conifer regeneration after 334 wildfires, using a dataset of postfire conifer regeneration from 10,230 field plots. Our findings highlight declining regeneration capacity across the West over the past four decades for the eight dominant conifer species studied. Postfire regeneration is sensitive to high-severity fire, which limits seed availability, and postfire climate, which influences seedling establishment. In the near-term, projected differences in recruitment probability between low- and high-severity fire scenarios were larger than projected climate change impacts for most species, suggesting that reductions in fire severity, and resultant impacts on seed availability, could partially offset expected climate-driven declines in postfire regeneration. Across 40 to 42% of the study area, we project postfire conifer regeneration to be likely following low-severity but not high-severity fire under future climate scenarios (2031 to 2050). However, increasingly warm, dry climate conditions are projected to eventually outweigh the influence of fire severity and seed availability. The percent of the study area considered unlikely to experience conifer regeneration, regardless of fire severity, increased from 5% in 1981 to 2000 to 26 to 31% by mid-century, highlighting a limited time window over which management actions that reduce fire severity may effectively support postfire conifer regeneration.

SUBMITTER: Davis KT

PROVIDER: S-EPMC10089158 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Reduced fire severity offers near-term buffer to climate-driven declines in conifer resilience across the western United States.

Davis Kimberley T KT Robles Marcos D MD Kemp Kerry B KB Higuera Philip E PE Chapman Teresa T Metlen Kerry L KL Peeler Jamie L JL Rodman Kyle C KC Woolley Travis T Addington Robert N RN Buma Brian J BJ Cansler C Alina CA Case Michael J MJ Collins Brandon M BM Coop Jonathan D JD Dobrowski Solomon Z SZ Gill Nathan S NS Haffey Collin C Harris Lucas B LB Harris Lucas B LB Harvey Brian J BJ Haugo Ryan D RD Hurteau Matthew D MD Kulakowski Dominik D Littlefield Caitlin E CE McCauley Lisa A LA Povak Nicholas N Shive Kristen L KL Smith Edward E Stevens Jens T JT Stevens-Rumann Camille S CS Taylor Alan H AH Tepley Alan J AJ Young Derek J N DJN Andrus Robert A RA Battaglia Mike A MA Berkey Julia K JK Busby Sebastian U SU Carlson Amanda R AR Chambers Marin E ME Dodson Erich Kyle EK Donato Daniel C DC Downing William M WM Fornwalt Paula J PJ Halofsky Joshua S JS Hoffman Ashley A Holz Andrés A Iniguez Jose M JM Krawchuk Meg A MA Kreider Mark R MR Larson Andrew J AJ Meigs Garrett W GW Roccaforte John Paul JP Rother Monica T MT Safford Hugh H Schaedel Michael M Sibold Jason S JS Singleton Megan P MP Turner Monica G MG Urza Alexandra K AK Clark-Wolf Kyra D KD Yocom Larissa L Fontaine Joseph B JB Campbell John L JL

Proceedings of the National Academy of Sciences of the United States of America 20230306 11

Increasing fire severity and warmer, drier postfire conditions are making forests in the western United States (West) vulnerable to ecological transformation. Yet, the relative importance of and interactions between these drivers of forest change remain unresolved, particularly over upcoming decades. Here, we assess how the interactive impacts of changing climate and wildfire activity influenced conifer regeneration after 334 wildfires, using a dataset of postfire conifer regeneration from 10,23 ...[more]

PMID: 36877837

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Dataset Information

Reduced fire severity offers near-term buffer to climate-driven declines in conifer resilience across the western United States.

Publications

Reduced fire severity offers near-term buffer to climate-driven declines in conifer resilience across the western United States.

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