Mixed-conifer understory response to climate change, nitrogen, and fire
Document Type: Journal Article
Author(s): Matthew D. Hurteau; Malcolm P. North
Publication Year: 2008

Cataloging Information

  • Abies concolor
  • Abies magnifica
  • Arabis
  • biomass
  • climate change
  • climate change
  • community ecology
  • coniferous forests
  • cover
  • disturbance
  • diversity
  • duff
  • experimental areas
  • fire intensity
  • fire management
  • fire regimes
  • fire size
  • forest fuels
  • forest management
  • fuel accumulation
  • fuel management
  • herbaceous vegetation
  • litter
  • mixed-conifer
  • Monardella
  • mountains
  • N - nitrogen
  • Nevada
  • nitrogen deposition
  • Pinus jeffreyi
  • Pinus lambertiana
  • Pinus ponderosa
  • pollution
  • precipitation
  • shrubs
  • Sierra Nevada
  • species diversity (plants)
  • understory vegetation
  • Viola spp.
  • Yosemite National Park
Partner Site(s):
  • Southwest FireCLIME
Record Maintained By:
Record Last Modified: February 29, 2020
FRAMES Record Number: 46891
Tall Timbers Record Number: 22724
TTRS Location Status: In-file
TTRS Call Number: Fire File
TTRS Abstract Status: Fair use, Okay, Reproduced by permission

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.


California's Sierra Nevada mountains are predicted to experience greater variation in annual precipitation according to climate change models, while nitrogen deposition from pollution continues to increase. These changes may significantly affect understory communities and fuels in forests where managers are attempting to restore historic conditions after a century of altered fire regimes. The objective of this research was to experimentally test the effects of increasing and decreasing snowpack depth, increasing nitrogen, and applying prescribed fire to mixed-conifer forest understories at two sites in the central and southern Sierra Nevada. Understory response to treatments significantly differed between sites with herb biomass increasing in shrub-dominated communities when snowpack was reduced. Fire was a more important factor in post-treatment species richness and cover than either snowpack addition or reduction. Nitrogen additions unexpectedly increased herbaceous species richness. These varied findings indicate that modeling future climatic influences on biodiversity may be more difficult than additive prediction based on increasing the ecosystem's two limiting growth resources. Increasing snowpack and nitrogen resulted in increased shrub biomass production at both sites and increased herb production at the southern site. This additional understory biomass has the potential to increase fuel connectivity in patchy Sierran mixed-conifer forests, increasing fire severity and size.

Online Link(s):
Hurteau, Matthew D.; North, Malcom P. 2008. Mixed-conifer understory response to climate change, nitrogen, and fire. Global Change Biology 14(7):1543-1552.