Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-27T07:50:33.463Z Has data issue: false hasContentIssue false
  • English
  • Français

A new procedure for studying the release and fixation of potassium ions in soil

Published online by Cambridge University Press:  27 March 2009

B. C. Matthews  and
P. H. T. Beckett
B. C. Matthews
Affiliation:
Ontario Agricultural College
P. H. T. Beckett
Affiliation:
Oxford University
Get access Rights & Permissions [Opens in a new window]

Extract

The relationship between the exchangeable potassium content of a soil and the activity ratio, aK/√(aCa+Mg), of the solution with which it is in ‘instantaneous equilibrium’ is a characteristic of the soil which is independent of the soil: solution ratio or the total electrolyte concentration (up to O·06 M) of the solution. It is unaffected by the transfer of substantial amounts of potassium ions to or from the fixed state. Hence instantaneous equilibrium curves provide a basis against which to measure the changes in exchangeable potassium content due to fixation and release. This procedure has the important advantages that all measurements are made in the solution phase and that the solutions in contact with the soil approximate to the natural soil solution.

The technique has been employed successfully in studying the fixation and release of potassium by several widely different soils.

The results confirm that fixation or release are determined by the extent to which the soil contains more or less exchangeable potassium than its equilibrium percentage potassium saturation. Seemingly the equilibrium percentage potassium saturation, and hence the equilibrium activity ratio of potassium in the soil solution aK/√(aCa+Mg), is regulated by the amounts or proportions of potassium in the fixed state. The amounts or proportions of potassium in the fixed state may be increased by repeated applications of potassium fertilizers and reduced by continued cropping.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 58 , Issue 1 , February 1962 , pp. 59 - 64
Copyright
Copyright © Cambridge University Press 1962

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Arnold, P. W. (1960). Nature, Lond., 187, 436.CrossRefGoogle Scholar
Beckett, P. H. T. (1958). D.Phil. Thesis. Oxford.Google Scholar
Beckett, P. H. T. & Fordham, A. W. (1961). Agrochimica (in the Press).Google Scholar
Guggenheim, E. A. (1950). Thermodynamics, An Advanced Treatise, pp. 314–18. North-Holland Publishing Co.Google Scholar
Matthews, B. C. & Sherrell, C. G. (1959). Canad. J. Soil Sci. 40, 35.CrossRefGoogle Scholar
Robinson, R. A. & Stokes, R. H. (1949). Trans. Faraday Soc. 45, 612.CrossRefGoogle Scholar
Schofield, R. K. (1947). Proc. 11th Int. Congr. Pure and Applied Chem. 3, 247.Google Scholar
Schofield, R. K. & Taylor, A. W. (1955). J. Soil Sci. 6, 137.CrossRefGoogle Scholar
Wear, J. I. & White, J. L. (1951). Soil Sci. 71, 1.CrossRefGoogle Scholar
Stanton, D. A. (1958). M.Sc. Thesis, University of Natal.Google Scholar