Soil-Geochemical Aspects of Land Use in Abandoned Land in Central Poland

It is observed increasing of abandoned land in Poland in last decade of 20^th century.The part of abandoned land is usually covered by birch tree community. The entrance of birches, especially on pure sandy area, changes properties of soil. The samples of soil horizons, litter in different stages of decomposition and leaves from birch trees, were taken into analysis. The role of birch was analysed also in comparison to arable land, abandoned land without trees and different ages birch trees communities. After the entrance birch trees soil profiles were enriched in nitrogen and elements such as aluminium, iron, cadmium, lead, cobalt, zinc, which were moved from soil or come from atmospheric load and were accumulated in litter or humus horizon. Compared to arable land, some elements (for example calcium) had lower concentration under birch trees. After several years without fertilization the relationship between elements were changed. In early stages (until 10 years) in litter horizons potassium prevails calcium, later – calcium prevails potassium. Birch trees made soil environment more natural compared to arable land.