EGU21-13342
https://doi.org/10.5194/egusphere-egu21-13342
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Holocene spatio-temporal patterns of biomass burning in the Bohemian-Bavarian Forest Mountains (Central Europe)

Gabriela Florescu1, Petr Kuneš1, Willy Tinner2, Marco Heurich3, Walter Finsinger4, Alice Moravcová1, Dagmar Dreslerová5, Gunther Kletetschka6, Daniel Vondrak7, and Vachel Carter1
Gabriela Florescu et al.
  • 1Department of Botany, Faculty of Science, Charles University, Prague, Czechia
  • 2Institute of Plant Sciences and Oeschger Centre for Climate Change Research, University of Bern, Switzerland
  • 3Department of Visitor Management and National Park Monitoring, Bavarian Forest National Park, Germany
  • 4ISEM, University Montpellier, CNRS, IRD, EPHE, Montpellier, France
  • 5Institute of Archaeology, Czech Academy of Sciences, Prague, Czechia
  • 6Institute of Hydrogeology, Engineering Geology and Applied Geophysics, Faculty of Science, Charles University, Prague, Czechia
  • 7Institute for Environmental Studies, Faculty of Science, Charles University, Prague, Czechia

Long-term perspectives on disturbance dynamics are important for the conservation of protected areas, yet restoration and conservation strategies in the Bohemian-Bavarian Forest Mountains do not consider the long-term role and patterns of forest fire, which is still deemed a negligible ecosystem disturbance in Central Europe. The scarcity of macroscopic charcoal studies in this area has likely hampered a complete understanding of local fire regime dynamics and its legacies in the present forest structure and composition. Here we used macroscopic charcoal (number, area and morphology of charred particles) and pollen analysis to investigate high resolution spatial and temporal patterns in Holocene fire regimes in the Bavarian-Bohemian Forest. We explored the relationship between changing forest composition dynamics and the influence topography had on spatial patterns of biomass burning. For this, we selected three lacustrine sites (two new, one published), located along a 30 km longitudinal transect within the studied area, at similar elevations in the mixed forest belt, with opposite (north vs. south) aspects. Results showed similar changes in biomass burning, fire frequency and peak magnitude at all sites, with a maximum during the early Holocene when fire resistant taxa (Pinus and Betula) dominated. Fire frequency decreased by half with the expansion of more fire-sensitive taxa (e.g., Picea and Fagus) during the mid-Holocene and reached a second maximum in the late Holocene, parallel with sustained increases in anthropogenic pollen indicators. We found a close north-south correspondence in the succession of fire patterns, i.e., fine-scale changes in biomass burning in the Bavarian Forest site (south-facing catchment) occurred around the same time with those observed at the Bohemian Forest sites (predominantly north-facing catchments), and these changes mirrored the Holocene dynamics of the main forest taxa. For example, the lowest biomass burning and peak magnitude intervals marked the beginning of Picea abies expansion at ~ 9 ka BP, Fagus sylvatica expansion at ~6 ka and Abies alba expansion at ~5 ka BP. Furthermore, we found a direct relationship between the abundance of charred morphotypes of conifer needles and deciduous leaves and the dominance of pine and birch in our pollen records, and a close correspondence between the abundance of non-woody charcoal morphotypes and pollen-derived landscape openness. Non-woody charcoal morphotypes dominated the charcoal records in the Early Holocene at the peak of biomass burning, whereas the abundance of woody morphotypes peaked around 6-8 ka BP and over the last millennium and their proportion in total charcoal influx increased starting 4 ka BP. Our study enables a better understanding of past and present fire regimes in the Bavarian-Bohemian Forest Mountains and highlights the need to consider the effects of fire as part of climate-change forest conservation strategies.

How to cite: Florescu, G., Kuneš, P., Tinner, W., Heurich, M., Finsinger, W., Moravcová, A., Dreslerová, D., Kletetschka, G., Vondrak, D., and Carter, V.: Holocene spatio-temporal patterns of biomass burning in the Bohemian-Bavarian Forest Mountains (Central Europe), EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-13342, https://doi.org/10.5194/egusphere-egu21-13342, 2021.

Display materials

Display file

Comments on the display material

to access the discussion