Phosphorus fixation in contrasting soils: Quantifying p-fixation capacity and implications for fertilizer management

Phosphorus (P) availability is often constrained by its fixation in soil, limiting crop productivity in many regions. A laboratory incubation study was conducted to quantify the phosphorus fixation capacity in two contrasting soil types: loamy sand (Anand) and clay loam (Devgadh Baria), Gujarat, India. Graded doses of phosphorus were added, and available P was estimated using Olsen’s method. Results showed strong linear relationships between added and available P, with fixation rates of 85.94% in Anand and 88.33% in Devgadh Baria. The higher fixation in clay loam was attributed to its greater clay content and organic matter. The findings highlight the need for site-specific phosphorus management strategies, especially in high-fixation soils, to enhance phosphorus use efficiency and wheat yield.