DESORPTION OF PHOSPHATE FROM SOILS USING ANION EXCHANGE RESINS |
| |
| Authors: | B W BACHE CHRISTINA IRELAND |
| |
| Institution: | The Macaulay Institute for Soil Research, Department of Soil Fertility, Craigiebuckler, Aberdeen AB9 2QJ |
| |
| Abstract: | After 100h reaction with Cl-resin and 300h reaction with HCO3-resin (approaching equilibrium), the concentration of anions complementary to phosphate was the critical variable affecting the transfer of P from soil to resin. Solution concentrations of H30+, Ca2+ and phosphate indicated that desorption of P by OH-, and dissolution of Ca phosphates, controlled P release from soils. P extracted by HCO3-resin was much greater than by Cl-resin from an acid soil, due to lower total anion and higher desorbing anion concentrations, but there was little difference between the two resins with a calcareous soil. HCO3-resin extracted a constant proportion of isotopically-exchangeable P from different soils whereas Cl-resin did not. Anion exchange resins provide a convenient means for producing P desorption curves for soils. |
| |
| Keywords: | |
|
|
