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The aims of this article are, first, to investigate the middle- and upper-Holocene woodland history along the altitudinal gradient between the lowlands and uplands of Central Europe (190–550 m a.s.l.) and, second, to outline possible biases inherent in the charcoal record based on a comparison with the pollen record and its known biases. Our anthracological data set contains 42,547 determinations made in 120 charcoal samples taken at 69 sites. The lowest elevated part of the study region (below 200 m a.s.l.) is characterized by the long-term presence of a species-rich hardwood forest (mixed oak–elm–ash forest). Quercus charcoals dominated in the rest of the altitude zones during the Neolithic and Aeneolithic; however, shrub charcoals appearing in samples from areas with chernozem soils (generally up to 230 m a.s.l.) indicate open-canopy oak woodlands. The species composition differed along the altitudinal gradient during the Bronze Age period, when Carpinus, Fagus and Abies expanded to altitudes above 230 m a.s.l., while Fagus was more abundant above 290 m a.s.l. Broadleaved trees (Quercus, Fraxinus, Ulmus, Acer and Carpinus) and shrubs are generally more represented in charcoals than pollen. Since broadleaved trees are usually nutrient demanding and able to re-grow easily after being felled, we suppose that their charcoal record is influenced by two main factors: bias of the initial location of the archaeological site and bias caused by long-term human influence on forest vegetation in the vicinity of settlements. These results underline that combining charcoal and pollen analysis has great potential for studying phenomena in cultural landscapes, as each of the methods approaches nature from the opposite side of the human–nature gradient. [ABSTRACT FROM AUTHOR]

The distribution pattern of relict and specialised species in calcareous fens was revealed to be non-stochastic, with ancient fens harbouring more of these species than younger ones. This phenomenon could be caused by long-lasting in situ survivals over millennia, but direct palaeoecological evidence is lacking. We addressed the question whether at least some ancient calcareous fens indeed retained open-fen patches throughout the Holocene, using a palaeoecological approach involving proxies with different taphonomies (pollen, vascular plants, bryophytes, molluscs). We identified three old fens in the Western Carpathians, where several postglacial relict species have recently been found, and we reconstructed their histories with respect to sedimentary processes, vegetation structure and dynamics of relict species. The development at all the sites started with a (semi)-open fen community dominated by sedges and brown mosses. The site with the highest recent number of relict species was reconstructed to harbour open patches continually since the late Glacial to the present, including the middle Holocene when open-fen patches were restricted. By contrast, at the site with the lowest recent number of relict species, a large sedimentary hiatus suggested peat mineralisation or erosion that prevented the survival of light-demanding species. At all the sites, characteristic snails of European Glacial periods occurred during fen initiation, but disappeared around the early/middle Holocene transition. The probability of a relict species being present in a modern fen community increases with fen age, but it also depends on the continual existence of open-fen patches and peat accumulation throughout the middle Holocene. [ABSTRACT FROM PUBLISHER]

We studied the relationships between surface pollen spectra, vegetation and selected climate characteristics along a strong gradient of climate continentality across the Western Sayan Mountains, southern Siberia. Representation of 111 pollen taxa in 81 surface samples from steppe, forest and tundra was related to the vegetation composition at various distances from the sampling point and to mean annual precipitation and mean July and January temperatures. These relationships were assessed by the decision tree models. The results show (1) which vegetation types are well distinguished by their pollen spectra; (2) which vegetation types are strongly similar in their pollen spectra and therefore their interpretation from fossil pollen spectra should be carefully considered; (3) tight relationship between surface pollen spectra and selected climate characteristics, which suggests that the past climatic conditions can be reasonably predicted from pollen spectra; and (4) an important role of weak pollen producers for assignment of pollen spectra to vegetation types or particular values of temperature and precipitation. We found the decision trees suitable for analysis of pollen/vegetation relationship because they (1) formally and precisely assign the pollen spectra to vegetation/landscape types or climatic variables by means of easy-to-interpret graphs; (2) identify pollen taxa that are best indicators of a particular vegetation type, landscape or climate characteristics; and (3) utilize the pollen signal of both strong and weak pollen producers. We compare the decision tree models with ordination and cluster analysis and suggest further applications. [ABSTRACT FROM AUTHOR]