The changes in inorganic and organic phosphorus (P) fractions of soil resulting from long-term fertilization (40 years) were investigated. In order to improve understanding of the sink and sources of phosphorus, P-fractions were extracted from soil samples of 0-30 and 30-60 cm depth with different amounts of monoammonium-phosphate (MAP) and then determined. Stagnosol was the type of the studied soil. Phosphate fertilizer was applied in 26, 39 and 52 kgP/ha amounts during the period of 40 years. Samples were subjected to sequential extraction according to the modified Chang and Jackson method and BCR (Community Bureau of Reference) sequential extraction procedure in order to extract different forms of phosphorus. The Certified Reference material CRM 684 (River Sediment Extractable Phosphorus) was used to provide accuracy of the instrument and both used methods. Furthermore, the association of phosphorus with substrates was provided by comparison of the results of sequential methods of phosphorus species with the sequential extraction of metals (Fe, Al, Mn and Ca). Results of continuous fertilization during 40 years indicated the increase of all the phosphorus forms in the soil except of phosphorus bound to calcium and organic phosphorus. Application of higher amounts of P-fertilizer resulted in dominance of Al-P fraction in studied soil which indicated that this fraction was the most responsible for the migration of phosphorus along the soil profile

Irreplaceability of phosphorus as a necessary macroelement in crop production is due to limited resources and costly processing of ores and immobilization in soil, which force for seeking an alternative sources or the use of waste materials. In this paper, the waste aluminum phosphate from pharmaceutical factory used as phosphate fertilizer and its effects were compared with other phosphorus fertilizers (superphosphate and rock phosphate). Except the analysis of available phosphorus (AL-method) the sequential extraction of phosphorus (modified Chang and Jackson) and sequential extraction of aluminum (modified Tessier) were performed. The experimental plant was mustard (Sinapis alba). The pot experiment was carried out on two soil types: Stagnosol and Vertisol. Application of phosphorus with aluminum phosphate had the same effect as the application of other phosphatic fertilizers in both soil types. In Stagnosol Al-phosphate directly influenced the increase in plant fresh weight by 39% and dry weight by 43% compared to the control, and also decreased the content of mobile Al for 40% and Pb for 47% in plant biomass. Based on these results, the use of waste aluminum phosphate has a potential to be used as a phosphorus fertilizer under given conditions.