Fig. 5. The desorption isotherm for the soils of the 5- and 10-cm treatments describing the relationship between the P concentration in 1:10 (w/v) 0.01 M CaCl₂ extracts and the total pool of sorbed P (P_ox corrected for the amount of P in the CaCl₂ extracts). The Langmuir equation was fitted to the data.