Late-Holocene human-induced changes to the extent of alpine areas in the East Sudetes, Central Europe

Abstract

The easternmost parts of the Hercynian mid-mountains of Central Europe, namely Hrubý Jeseník and Králický Sněžník, are characterised by extensive alpine areas at altitudes above approximately 1300 m a.s.l. In order to determine the contribution of human activities to the extent of these summit grasslands we analysed charcoal assemblages and pollen profiles taken from high elevation sites. The first burn was dated to the Iron Age (about the first to second centuries BC), with successive fire events recorded in the early Mediaeval epoch from about AD 670. Significant human influence as recorded in pollen diagrams was detected as late as during the High Middle Ages (about the twelfth to thirteenth centuries AD). Charcoal assemblages reveal similar trends in species composition. The oldest and/or deepest samples are represented by charcoal fragments of Picea abies and various broadleaf trees and shrubs such as Betula sp., Sorbus sp., Juniperus sp. and Salix sp. Towards the surface, Picea abies gradually becomes dominant and then Vaccinium charcoal particles dominate the charcoal pool. Radiocarbon data of individual charcoal fragments did not, however, confirm a stratification of charcoal in the soil. According to anthracomass, pollen and macrofossils, the pattern of forest-free areas was originally determined by terrain morphology. While forest-free patches occurred on exposed summits and the convex edges of summit plateaus, open canopy tree growths dominated high elevation summit flats, and closed canopy forests occurred on adjacent slopes.