The relations between phosphorus fractions and some soil properties in soils forming on calcareous parent material

Phosphorus (P) is essential to all known life forms because it is a key element in many physiological and biochemical processes. Soil properties due to soil formation processes and land use have impacts on the availability of phosphorus in soils and on the change in geochemical fractions. Thus, total of 71 surface soil samples (0-20 cm) were taken from the Atabey Plain. The sequential extraction procedure was executed in the samples. The determined fractions were: sodium bicarbonate [NaHCO3-P (organic Po, inorganic Pi and Total Pt)], sodium hydroxide [NaOH-P (organic Po, inorganic Pi and Total Pt)], citrate bicarbonate dithionite (CBD-P), hydrochloric acid (Ca-P), and residual (Res-P) phosphorus. Relations of phosphorus fractions with soil properties were revealed by descriptive statistics, Pearson correlation analysis and chemometric analysis. The average distribution of fractions in the plain soils in descending order were: Ca-P (% 50.36) > Res-P (% 19.94) > CBD-P (% 12.17) > NaOH-Pi(% 6.24) > NaHCO3-Pi(% 1.57) > NaOH-Po (% 0.71) > NaHCO3-Po (% 0.25). It was determined that the fractal distribution of these fractions changed according to the land use pattern-dependent on fertilizer usage