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Cited by 62Fire effects on ecosystemsSoil Carbon and Nitrogen DynamicsSoil and Environmental Studies

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Thermal alteration of soil organic matter properties: a systematic study to infer response of Sierra Nevada climosequence soils to forest fires

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Araya, Samuel N., Fogel, Marilyn L., Berhe, Asmeret Asefaw·2017·SOIL
DOI 10.5194/soil-3-31-2017

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Abstract

Abstract. Fire is a major driver of soil organic matter (SOM) dynamics, and contemporary global climate change is changing global fire regimes. We conducted laboratory heating experiments on soils from five locations across the western Sierra Nevada climosequence to investigate thermal alteration of SOM properties and determine temperature thresholds for major shifts in SOM properties. Topsoils (0 to 5 cm depth) were exposed to a range of temperatures that are expected during prescribed and wild fires (150, 250, 350, 450, 550, and 650 °C). With increase in temperature, we found that the concentrations of carbon (C) and nitrogen (N) decreased in a similar pattern among all five soils that varied considerably in their original SOM concentrations and mineralogies. Soils were separated into discrete size classes by dry sieving. The C and N concentrations in the larger aggregate size fractions (2–0.25 mm) decreased with an increase in temperature, so that at 450 °C the remaining C and N were almost entirely associated with the smaller aggregate size fractions ( < 0.25 mm). We observed a general trend of 13C enrichment with temperature increase. There was also 15N enrichment with temperature increase, followed by 15N depletion when temperature increased beyond 350 °C. For all the measured variables, the largest physical, chemical, elemental, and isotopic changes occurred at the mid-intensity fire temperatures, i.e., 350 and 450 °C. The magnitude of the observed changes in SOM composition and distribution in three aggregate size classes, as well as the temperature thresholds for critical changes in physical and chemical properties of soils (such as specific surface area, pH, cation exchange capacity), suggest that transformation and loss of SOM are the principal responses in heated soils. Findings from this systematic investigation of soil and SOM response to heating are critical for predicting how soils are likely to be affected by future climate and fire regimes.

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  • Fire directly impacts the upper organic horizons via pyrolysis and combustion reactions, including physical loss of the organic horizon, and the underlying mineral soil by conductive and advective heating during a fire.

    “Fire directly impacts the upper organic horizons via pyrolysis and combustion reactions, including physical loss of the organic horizon, and the underlying mineral soil by conductive and advective heating during a fire (Araya, Fogel, & Berhe, 2017;Certini, 2005;Neary, Ryan, & DeBano, 2008).”

    From Fire as a fundamental ecological process: Research advances and frontiers (2020) · cites this paper as Araya et al., 2017

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Cited by

Sorted by citations

  • Fire as a fundamental ecological process: Research advances and frontiers

    McLauchlan, K. K., Higuera, P. E., Miesel, J., Rogers, B. M., Schweitzer, J., Shuman, J. K., Tepley, A. J., Varner, J. M., Veblen, T. T., Adalsteinsson, S. A., et al. (2020) · Journal of Ecology · doi:10.1111/1365-2745.13403 · Cited by 729

    “Fire directly impacts the upper organic horizons via pyrolysis and combustion reactions, including physical loss of the organic horizon, and the underlying mineral soil by conductive and advective heating during a fire (Araya, Fogel, & Berhe, 2017; Certini, 2 005; Neary, Ryan, & DeBano, 2008).”

Metadata

Authors
Araya, S. N., Fogel, M. L., & Berhe, A. A.
Affiliations
University of California, Merced (US)
Corresponding author
  • Araya, Samuel N.
  • Fogel, Marilyn L.
  • Berhe, Asmeret Asefaw
ORCID
Venue
SOIL
Publisher
Copernicus GmbH
Published
2017-02-06
Volume
3
Issue
1
Pages
31-44
ISSN
  • 2199-3971 (ISSN-L)
  • 2199-398X
DOI
10.5194/soil-3-31-2017
OpenAlex
W2494819419
Cited by
62
References
1
Citations by year
2026: 3 · 2025: 7 · 2024: 10 · 2023: 4 · 2022: 6 · 2021: 8 · 2020: 7 · 2019: 6 · 2018: 5 · 2017: 3
FWCI
3.98
Type
journal article
Language
en
Open access
Licence
Locations
  • SOIL (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Topics
  • Physical Sciences › Environmental Science › Global and Planetary Change › Fire effects on ecosystems
  • Life Sciences › Agricultural and Biological Sciences › Soil Science › Soil Carbon and Nitrogen Dynamics
  • Life Sciences › Agricultural and Biological Sciences › Soil Science › Soil and Environmental Studies
Keywords
soil organic matter, thermal alteration, fire regimes, prescribed burning, forest fires, soil carbon, soil nitrogen, stable isotopes, 13C enrichment, 15N enrichment, aggregate size fractions, temperature thresholds, soil mineralogy, soil organic matter loss, climate change

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