Fig. 2. Relationships between Mehlich 3 P and (a) water soluble P (WSP), (b)Fe oxide strip P (FeO-P), and (c) degree of P saturation via the oxalate method (DPS_ox) for all 465 soils used in the study. Dashed vertical lines represent the agronomic critical value for Melich 3-P (50 mg kg^-1) and dashed horizontal lines represent the corresponding values for WSP, FeO-P, and DPS_ox, as derived from the linear regression equations in each graph.

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