Speaker
Description
Climate change is one of the most challenging problems facing humanity. Depending on climate conditions and vegetation composition, a fire regime changes threat previously relatively fire-free regions. East-European forest-steppe is an economically important ecotone between arid steppe and mesophilic forest. To assess the possible fire risks induced by the current climate warming we conducted a study on the past vegetation and fire dynamics of the central and southern parts of the East-European forest-steppe. Two sediment cores covering the last ~14.8 and 9.8 thousand years were studied for pollen, non-pollen palynomorphs, botanical macro-remains, macro- and micro-charcoal. Using modern analogue technique, we reconstructed forest cover to examine its correlation with the wildfires’ frequency and intensity and the potential climate forcing. Micro- and macro-charcoal concentration and influx were low during the Late Glacial (14.8–12.5 cal. kyr BP), suggesting low fire activity. Fire activity strongly increased during the Younger Dryas and the early Holocene, corresponding to spread of pine forest-steppe. Charcoal loads decreased at ~7 cal. kyr BP possibly due to the decrease in forest cover and/or a change in forest composition. After the development of the mixed-broadleaf forest-steppe ~4.2 kyr BP, local forest wildfires were no longer detected. Charcoal maxima in the late Holocene are strongly related to the increased human impact.
