Influence of human activity on the development of aeolian processes in the Silesian-Cracow Upland (Poland)

In Poland, first traces of human activity on dunes and areas of aeolian cover sands were observed in the Vistulian period. Man, however, was not an essential factor in the mobilisation of drift sands at the time because his main occupation was hunting and nemoriculture. At the beginning of the Holocene, the situation was not different. Intensive aeolian processes caused by human interference in the natural dune environments took place in the Sub-Boreal and Sub-Atlantic periods. It is assumed that they mainly consisted in the translocation of Late-Glacial dunes and the formation of thick and loose sandy series which were not of larger morphological significance (although Holocene dunes are also known). Aeolian series are frequently divided by fossil soils (mostly humus horizons) in which the occurrence of charcoal and pollen of synanthropic plants indicates pasturing and agricultural activity. Moreover, in dune sands, numerous artifacts belonging to different cultures have been found.The paper focuses on a synthesis of anthropogenically induced aeolian processes in the Silesian-Cracow Upland that has been the main area of investigation carried out by the Geographical Centre of the Silesian University in Sosnowiec, Poland. The research hypothesis is as follows: the Holocene aeolian processes in the Silesian-Cracow Upland are to a large extent related to activity of man, who used natural conditions of the region. The aim of this study is to analyse human-induced changes recorded in aeolian deposits and relief of this upland from a historical perspective against a background of the Holocene aeolian processes in Poland. To achieve this aim, we used numerous C14 datings, palynological analyses, archaeological finds (the reference to archaeological research being rather cursory), historical information, structural measurements and analyses of sand grain-size, analyses of archival and present cartographic materials, aerial photos and instrumental and non-instrumental observations of aeolian processes. Finally, periods of human interference recorded in aeolian deposits and relief have been distinguished. They are as follows: the Atlantic, the Sub-Boreal, the Sub-Atlantic, including the last millennium with a period of direct field observations, an analysis of changes and developmental tendencies of relief and determination of wind processes dynamics.