Changes in soil phosphorus fractions in response to long?term phosphate fertilization under sole cropping and intercropping of maize and faba bean on a calcareous soil

Understanding how soil phosphorus (P) fractions change is critical to achieve more efficient P use in a highly P-sorbing calcareous soil. The fields were managed without or with annual fertilizer (40 kg ha? 1), continuously growing sole cropping intercropping of maize and faba bean. Soil samples (0–200 mm) collected at the start experiment eight years later, we evaluated using sequential fractionation. Maize/faba bean had an average land equivalent ratio (LER) 1.2, similar content as maize, while both acquired than Compared original 2009, three systems, regardless fertilization, depleted labile pool (Resin-P NaHCO3-Pi), Residual-P NaHCO3-Po accumulated. Eight no input showed mainly NaOH-Pi conc. HCl-Pi, depleting NaOH-Po, most abundant fraction, 1 M addition NaOH-Pi. However, long-term application caused systems accumulate HCl-Pi HCl-Po fraction; accumulation NaOH-Pi, NaOH-Po. Long-term appropriate enhanced mineralization mod-labile non-labile organic inorganic P. Sole consistently P, accessed pools varying input.