The pH changes of the soils formed as a result of reclamation of the sand-pits

The alluvial soils in the Bóbr river valley, devastated by sand and gravel exploitation, were reclaimed for agricultural use. After reclamation treatment, the newly formed soil was very acid. Application of 5 Mg/ha lime elevated soil pH to 6-7, but during the following years, soil pH dropped again by about one half of the pH unit a year. Rapid drop in the pH level can result both from geological and soil-forming processes. Efficiency of mineral fertilizers applied in various combinations did not give the expected results and the yield of cultivated plants was not satisfactory. Mineral fertilization in various combinations did not result in the expected yield levels.