12,000-Years of fire regime drivers in the lowlands of Transylvania (Central-Eastern Europe): a data-model approach

Feurdean, A; Liakka, J; Vannière, B; Marinova, E; Hutchinson, SM; Mosburgger, V; Hickler, T

Abstract

The usefulness of sedimentary charcoal records to document centennial to millennial scale trends in aspects of fire regimes (frequency, severity) is widely acknowledged, yet the long-term variability in these regimes is poorly understood. Here, we use a high-resolution, multi-proxy analysis of a lacustrine sequence located in the lowlands of Transylvania (NW Romania), alongside global climate simulations in order to disentangle the drivers of fire regimes in this dry climatic region of Central-Eastern Europe. Periods of greater fire activity and frequency occurred between 10,700 and 7100 cal yr BP (mean Fire
Interval ¼ mFI 112 yr), and between 3300 and 700 cal yr BP (mFI 150 yr), whereas intervals of lower fire activity were recorded between 12,000 and 10,700 cal yr BP (mFI 217 yr), 7100 and 3300 cal yr BP (mFI 317 yr), and over last 700 years (no fire events detected).We found good correlations between simulated early summer (June, July) soil moisture content and near-surface air temperature with fire activity,
particularly for the early to mid Holocene. A climateefire relationship is further supported by local hydrological changes, i.e., lake level and runoff fluctuations. Fuel limitation, as a result of arid and strongly seasonal climatic conditions, led to low fire activity before 10,700 cal yr BP. However, fires were most frequent during climatically drier phases for the remaining, fuel-sufficient, part of the Holocene. Our results also suggest that the occurrence of more frequent fires in the early Holocene has kept woodlands open, promoted grassland abundance and sustained a more flammable ecosystem (mFI < 150 years) whereas the decline in fire risk under cooler and wetter climate conditions (mFI ¼ 317 years) favoured woodland development. From 3300 cal yr BP, human impacts clearly were partly responsible for changes in fire activity, first increasing fire frequency and severity in periods with fire-favourable climatic conditions (halving the mFI from 300 years to about 150 years), then effectively
suppressing fires over the last several centuries. Given the projected future temperature increase and moisture decline and the biomass accumulation due to the agricultural land abandonment in the region,natural fire frequency would be expected to return to <150 years.

A. a,b,*, J. b, B. c, E. d, S.M. Hutchinson e, V. a,
T.

Citation

Feurdean, A., Liakka, J., Vannière, B., Marinova, E., Hutchinson, S., Mosburgger, V., & Hickler, T. (2013). 12,000-Years of fire regime drivers in the lowlands of Transylvania (Central-Eastern Europe): a data-model approach. Quaternary Science Reviews, 81, 48-61. https://doi.org/10.1016/j.quascirev.2013.09.014

• Journal Article Type: Article
• Publication Date: Jan 1, 2013
• Deposit Date: May 8, 2015
• Journal: Quaternary Science Reviews
• Print ISSN: 0277-3791
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 81
• Pages: 48-61
• DOI: https://doi.org/10.1016/j.quascirev.2013.09.014
• Publisher URL: http://dx.doi.org/10.1016/j.quascirev.2013.09.014
• Related Public URLs: http://www.journals.elsevier.com/quaternary-science-reviews/
• Additional Information: Funders : Funder not known