Historical background

Agricultural activities on the present area of Poland date back to the warm, moist Atlantic climatic phase (5500–3000 BC) of the post-glacial epoch (Hensel and Tabaczynski, 1978). At the time, human impact on the environment was too insignificant to stimulate erosion processes and alter the natural cycles of matter. With rising population density and the invention of more powerful tools, considerable portions of the upland areas of southern Poland were cleared of forests to take advantage of their loess soil which was good for cultivation and rather easy to till. The probable decline of soil fertility in loess upland during the dry subboreal phase of the post-glacial period (3000–800 BC) may explain an expansion of the cultivation in other areas (Hensel and Tabaczynski, 1978). In the Iron Age, fuel demand for primitive smelting furnaces was another cause of deforestation. In Poland, iron metallurgy began its intense development in the 3rd and 4th centuries AD in the Swietokrzyskie Mountains, and by the end of the 4th century AD the population density was estimated to be three per square kilometer (Zak, 1978). At that time, loess areas of the Lublin uplands, and Malopolska Region, were almost totally deforested. This resulted in intensification of erosion processes, which is manifested by significant deposits of eroded soil at slope bases, formed in the period AD 500–1000 (Strzemski, 1964).