Change search
ReferencesLink to record
Permanent link

Direct link
Early-season fires in boreal black spruce forests produce pyrogenic carbon with low intrinsic recalcitrance
Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. Univ Alberta, Dept Renewable Resources, Edmonton, AB T6G 2R3, Canada.
2015 (English)In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 96, no 6, 1575-1585 p.Article in journal (Refereed) Published
Abstract [en]

Pyrogenic carbon (PyC), a major by-product of wildfires in boreal forests, plays several critical roles in soil biogeochemical processes. However, PyC properties, including its potential recalcitrance, may vary depending on its formation conditions. Our study aimed to characterize the chemical and physical properties of PyC formed under variable fire severity in Eastern Canada boreal forests; these latter represent an important fraction of fire-affected circumboreal ecosystems. A total of 267 PyC samples, produced by early-season wildfires in 2005-2007, were collected <= 5 years after fire from the forest floors of 14 black spruce sites distributed across Quebec, to cover the range of fire severity encountered in these forests. Early-season fires occur frequently in Eastern Canada, and are predicted to increase in regional and global scenarios of future fire regimes associated with climate change. Selected PyC samples were analyzed using elemental analysis, solid-state C-13 nuclear magnetic resonance (NMR) spectroscopy, scanning electron microscopy, and surface area analysis. The NMR spectra of the PyC collected on low-fire-severity sites were dominated by peaks indicative of cellulose, while those for PyC from higher-severity sites were dominated by a broad peak assigned to aromatic carbons. Atomic H/C and O/C ratios decreased with increasing fire severity. By comparing field samples to samples produced in the laboratory under controlled formation conditions, we were able to infer that the temperature of formation in the field was low (75 degrees-250 degrees C). In addition, for all PyC samples, the aromatic carbon : total carbon ratio was small, suggesting that PyC produced by early-season fires in these boreal forests may be susceptible to relatively rapid degradation. Taken together, our data suggest that boreal PyC may not be as recalcitrant as previously assumed, and that its influence on soil biogeochemical processes may be short lived.

Place, publisher, year, edition, pages
2015. Vol. 96, no 6, 1575-1585 p.
Keyword [en]
C-13 NMR, boreal forest, Canada, fire severity, forest floor, pyrogenic carbon
National Category
URN: urn:nbn:se:umu:diva-106023DOI: 10.1890/14-1196.1.smISI: 000356021700013OAI: diva2:839973
Available from: 2015-07-06 Created: 2015-07-03 Last updated: 2015-07-06Bibliographically approved

Open Access in DiVA

fulltext(845 kB)61 downloads
File information
File name FULLTEXT01.pdfFile size 845 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Soucemarianadin, Laure N.
By organisation
Department of Medical Biochemistry and Biophysics
In the same journal

Search outside of DiVA

GoogleGoogle Scholar
Total: 61 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 39 hits
ReferencesLink to record
Permanent link

Direct link