Fig. 1. Concentrations of phosphorus extracted by deionized water (H₂O-P), 0.5 M NaHCO₃ (pH 8.5, NaHCO₃–P), 0.1 M NaOH (NaOH-P), and 1 M HCl (HCl-P) and residual P fraction in pig manure as influenced by diet manipulation. Columns indicated with the same letter in the same group were not significantly different from one another (p > 0.10). BMP, barley–micronized pea; BMPE, barley–micronized pea with enzyme; BRP, barley–raw pea; BRPE, barley–raw pea with enzyme.