Vegetational changes in the montane grassland zone of the High Bieszczady mountains (southeast Poland) during the last millennium—pollen records from deposits in hanging peat-bogs

The pollen analytical investigations of hanging peat bogs in the summit zone of the Polish east Carpathians show that the absence of the upper montane spruce zone in the western Bieszczady mountains is a phenomenon that has been historically stable at least for the last millennium and probably also in earlier times. At altitudes corresponding to the spruce zone in other parts of the Carpathians, dwarf beech woods form here a low-lying upper tree limit. The montane grassland zone occurring above this tree line did not result from human activities, although it has been extended by human activity. Besides, it is shown how far it is possible to reconstruct from a pollen diagram the differentiation of vegetation surrounding the site of profile collection located in the upper montane zone when the present-day local plant communities are well known, in spite of pollen from long distance transport always being present at the summits of mountain ranges.