Skip to Main Content
Wildfires and climate change push low-elevation forests across a critical climate threshold for tree regenerationAuthor(s): Kimberley T. Davis; Solomon Z. Dobrowski; Philip E. Higuera; Zachary A. Holden; Thomas T. Veblen; Monica T. Rother; Sean A. Parks; Anna Sala; Marco P. Maneta
Source: PNAS Latest Articles. doi: 10.1073/pnas.1815107116.
Publication Series: Scientific Journal (JRNL)
Station: Rocky Mountain Research Station
Download Publication (1.0 MB)
DescriptionClimate change is increasing fire activity in the western United States, which has the potential to accelerate climate-induced shifts in vegetation communities. Wildfire can catalyze vegetation change by killing adult trees that could otherwise persist in climate conditions no longer suitable for seedling establishment and survival. Recently documented declines in postfire conifer recruitment in thewestern United States may be an example of this phenomenon. However, the role of annual climate variation and its interaction with long-term climate trends in driving these changes is poorly resolved. Here we examine the relationship between annual climate and postfire tree regeneration of two dominant, low-elevation conifers (ponderosa pine and Douglas-fir) using annually resolved establishment dates from 2,935 destructively sampled trees from 33 wildfires across four regions in the western United States. We show that regeneration had a nonlinear response to annual climate conditions, with distinct thresholds for recruitment based on vapor pressure deficit, soil moisture, and maximum surface temperature. At dry sites across our study region, seasonal to annual climate conditions over the past 20 years have crossed these thresholds, such that conditions have become increasingly unsuitable for regeneration. High fire severity and low seed availability further reduced the probability of postfire regeneration. Together, our results demonstrate that climate change combined with high severity fire is leading to increasingly fewer opportunities for seedlings to establish after wildfires and may lead to ecosystem transitions in low-elevation ponderosa pine and Douglas-fir forests across the western United States.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationDavis, Kimberley T.; Dobrowski, Solomon Z.; Higuera, Philip E.; Holden, Zachary A.; Veblen, Thomas T.; Rother, Monica T.; Parks, Sean A.; Sala, Anna; Maneta, Marco P. 2019. Wildfires and climate change push low-elevation forests across a critical climate threshold for tree regeneration. PNAS Latest Articles. doi: 10.1073/pnas.1815107116.
Keywordsecosystem transition, climate change, wildfire, ponderosa pine, Douglas-fir
- Fire-catalyzed vegetation shifts in ponderosa pine and Douglas-fir forests of the western United States
- Restoring ponderosa pine in the Davis Mountains of west Texas: impacts of planting practices on seedling survival
- What drives ponderosa pine regeneration following wildfire in the western United States?
XML: View XML