Investigations on phosphorus (P) distribution in a naturally acid and limed moraine loam, Bathypogleyic Dystric Glossic Retisol were conducted in a site of a long-term experiment at the Vėžaičiai Branch of Lithuanian Research Centre for Agriculture and Forestry in 2008 and 2011. The aim of the present study was to determine the distribution of different phosphorus forms and fractions in naturally acid soil limed for a long time (62 years). During this study different amounts (18.4 and 104.9 t ha -1 ) of lime materials were incorporated into the soil and affected the formation of two soil pH KCl levels -acidic (5.6) and near to neutral (6.7). Seven different organic and mineral phosphate fractions and plant-available phosphorus were determined in the soil. The long-term soil liming was found to have no significant effect on the total P content and its distribution, but caused the changes in the proportions between the different phosphorus forms. Major part of mineral (74.02-83.68%) and organic (88.9-93.8%) P was composed of Al and Fe phosphates. Soil liming using ×2.0 liming rates every 3-4 years influenced a significant increase of the phosphates (AlPO 4 and Al(Fe)PO 4 ) little-available to plants obtained by the second cycle of extraction. It was determined that when soil pH becomes near to neutral, water soluble and plant-available P increases compared to its value measured at native pH. Increase of soil pH KCl till 6.7 had a significant effect on the amount of little plant-available Ca phosphates and less soluble organic phosphorus fraction amount in soil. The relatively optimal amounts of phosphorus fractions available for plants were determined in the soil with a pH KCl of 5.6, achieved by liming with a 0.5 rate every 7 years.

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A long-term crop rotation experiment was established in Central Lithuania (Skėmiai, Radviliškis region) in 1971 (lysimeters were installed in 1976) on a sandy loamy Endocalcari-Endohypogleyic Cambisol (CMg-n-w-can). The effect of regular fertilisation with different rates and combinations of NPK fertilisers in a crop rotation (winter wheat → sugar beet → spring barley → spring rape → annual grasses and perennial grasses) on the concentrations of cations (Ca , respectively. Low levels of potassium leaching had little effect on potassium balance in the soil. Sodium leaching level did not exceed 7.67 kg ha -1 Na + in winter and 3.39 kg ha -1 Na + in summer. Application of mineral fertilisers resulted in sodium leaching increase by 5.77 kg ha -1 Na + on an average; potassium fertilisation encouraged the process of sodium leaching. As a result of intensive fertilisation the concentrations of calcium and magnesium ions in lysimeter water sampled at 80 cm depth were slightly higher than in the lysimeter water at 40 cm depth, the concentration of potassium ions -lower, and the concentration of sodium ions -about the same.