Desorption of Copper in Calcareous Soils

The desorption of copper in calcareous soils (Calciorthents) conformed to the linear form of the Langmuir equation. The desorption maximum, a constant related to mobility of copper in soils, was calculated from the experimental data. The sequential desorption of copper indicates that 1M NH₄OAc extracted relatively lower amount of adsorbed copper than those by complexing agents. These extractants provide a measure of different chemical pools of copper in these soils. The values of constant (K_D) related to the mobility of solid phase copper were greater for DTPA-CaCl₂ than for 1M NH₄OAc extractant. A highly significant relationship between supply parameter and cumulative desorption of copper was noted in mnst of the soils (r = 0.99**).