Abstract
BECKETT1,2 has discussed potassium–calcium exchange energies in soil suspensions, using a development of a thermodynamic approach suggested by Woodruff3 and Schofield and Taylor4. He showed that a graph of the “activity ratio” (called ARK) in the solution plotted against the changes in exchangeable soil potassium (ΔK) is usually linear except at small values of ARK where it curves sharply and becomes asymptotic to the ΔK axis (Fig. 2). ARK is directly related to the change in free energy when equivalent amounts of potassium and calcium are exchanged between the soil and solution phases. Beckett2 considers that the curvature is produced by a small proportion of potassium ions held on discrete exchange sites with a greater preference for potassium relative to calcium. These sites determine the exchange energy when nearly all the exchangeable potassium is removed. Very recently he has found evidence of similar behaviour for calcium and magnesium5.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on SpringerLink
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Beckett, P. H. T., J. Soil Sci., 15, 9 (1964).
Beckett, P. H. T., Soil Sci., 97, 376 (1964).
Woodruff, C. M., Soil Sci. Soc. Amer. Proc., 19, 36, 98 and 167 (1955).
Schofield, R. K., and Taylor, A. W., J. Soil Sci., 6, 137 (1955).
Beckett, P. H. T., Soil Sci., 100, 118 (1965).
Bolt, G. H., Soil Sci., 79, 267 (1955).
Bower, C. A., Soil Sci., 88, 32 (1959).
Pratt, P. F., Whittig, L. D., and Grover, B. L., Soil Sci. Soc. Amer. Proc., 26, 227 (1962).
Levy, R., and Mor, E., Soil Sci., 98, 152 (1964).
Schultz, R. K., Overstreet, R., and Barshad, I., Soil Sci., 99, 161 (1964).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
TINKER, P., BOLTON, J. Exchange Equilibria of Sodium on Some British Soils. Nature 212, 548 (1966). https://doi.org/10.1038/212548a0
Issue date:
DOI: https://doi.org/10.1038/212548a0
This article is cited by
-
The effect of chemical and organic amendments on sodium exchange equilibria in a calcareous sodic soil
Environmental Monitoring and Assessment (2015)