Stratigraphic Charcoal Analysis on Petrographic Thin Sections

Application to Fire History in Northwestern Minnesota

Dados Bibliográficos

ID23388479
AutoresJune S Clark (0000-0002-5677-9733, University of Minnesota, autor correspondente), James S Clark
Ano1988
Volume30
Fascículo1
Páginas81-91
Data de publicação1988-07-01
Peer ReviewedSim
Open AccessSim
TipoARTICLE
PeriódicoQuaternary Research (JOURNAL)
Identificadores do periódicoISSN: 0033-5894 • E-ISSN: 1096-0287
EditoraCambridge University Press (CUP) (PUBLISHER)
DOI10.1016/0033-5894(88)90089-0
OpenAlexW2083896809
IdiomaEN
Citações recebidas88
Referências citadas26

Results of stratigraphic charcoal analysis from thin sections of varved lake sediments have been compared with fire scars on red pine trees in northwestern Minnesota to determine if charcoal data accurately reflect fire regimes. Pollen and opaque-spherule analyses were completed from a short core to confirm that laminations were annual over the last 350 yr. A good correspondence was found between fossil-charcoal and fire-scar data. Individual fires could be identified as specific peaks in the charcoal curves, and times of reduced fire frequency were reflected in the charcoal data. Charcoal was absent during the fire-suppression era from 1920 A.D. to the present. Distinct charcoal maxima from 1864 to 1920 occurred at times of fire within the lake catchment. Fire was less frequent during the 19th century, and charcoal was substantially less abundant. Fire was frequent from 1760 to 1815, and charcoal was abundant continuously. Fire scars and fossil charcoal indicate that fires did not occur during 1730–1750 and 1670–1700. Several fires occurred from 1640 to 1670 and 1700 to 1730. Charcoal counted from pollen preparations in the area generally do not show this changing fire regime. Simulated “sampling” of the thin-section data in a fashion comparable to pollen-slide methods suggests that sampling alone is not sufficient to account for differences between the two methods. Integrating annual charcoal values in this fashion still produced much higher resolution than the pollen-slide method, and the postfire suppression decline of charcoal characteristic of my method (but not of pollen slides) is still evident. Consideration of the differences in size of fragments counted by the two methods is necessary to explain charcoal representation in lake sediments.

Archaeology · Biology · Botany · Charcoal · Climate change · Fire history · Geography · Palynology · Physical geography · Pollen · Varve · Chemistry · Fire effects on ecosystems · Geology · Geology and Paleoclimatology Research · Isotope Analysis in Ecology · Oceanography · Paleontology