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An evaluation of the properties of soil potassium influencing its supply by diffusion to plant roots in soil

Published online by Cambridge University Press:  27 March 2009

R. Bagshaw ,
L. V. Vaidyanathan  and
P. H. Nye
R. Bagshaw
Affiliation:
Soil Science Laboratory, Oxford University
L. V. Vaidyanathan
Affiliation:
Soil Science Laboratory, Oxford University
P. H. Nye
Affiliation:
Soil Science Laboratory, Oxford University
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Summary

K+ uptakes from forty-four arable soils from England by 1 cm portions of the roots of intact onion seedlings during 10 days growth were measured. A single-split-root arrangement was used, enabling the determination of uptake by known surface area of the root. Transpiration was restricted to make K+ diffusion in the soil the predominant supply mechanism. These were compared with calculated values using separately determined K+ diffusion coefficients in the soils.

Two methods were followed, namely (a) measuring K+ diffusion to a hydrogen form of cation exchange resin paper and calculating diffusion coefficients assuming total depletion of the (ammonium acetate) exchangeable K+ at the resin paper: soil boundary; and (b) deriving diffusion coefficients from estimated values of the impedance factor and the measured K+ buffer power of each soil, for 50, 60, 90 and 100% depletion of the initial soil solution K+at the root:soil boundary. None of the predictions adequately accounted for the observed uptake. Calculations of the root:soil boundary concentrations showed a wide range of depletion. Soils with initial soil solution K+ in the range 0.04–0.4 μmoles/ml were depleted of the solution K+ to near zero or even less. A negative concentration of K+ in solution indicates the probable contribution of non-exchangeable K+. When the initial soil solution K+ was more than 0.4 μmoles/ml, the uptake of K+ could be accounted for by 30–85 % depletion at the root:soil boundary.

Partial and multiple regression of the measured uptake on the initial exchangeable K+ content and the initial soil solution K+ concentration were calculated. A simple relationship between the uptake and the exchangeable K+ content accounted for about three-quarters the variance. The uptake was less closely associated with the K+ in solution or its ratio to Ca2+ + Mg2+ in solution. These correlations are discussed from the diffusion point of view and in relation to the usually reported correlations from pot experiments.

Potato yield response to K+ fertilizer additions in field experiments are examined in relation to the supply of K+ by diffusion in the soils. When K+ uptake by 1 cm portion of onion root from the unfertilized soil exceeded l.2 μmoles/10 days, yield response to K+ addition became erratic and occasionally negative.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 73 , Issue 1 , August 1969 , pp. 1 - 14
Copyright
Copyright © Cambridge University Press 1969

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References

REFERENCES

Arnold, P. W. (1962 a). The potassium status of some English soils considered as a problem of energy relationships. Proc. Fertil. Soc. 72, 25–55.Google Scholar
Arnold, P. W. (1962 b). Soil potassium and its availability to plants. Outl. on Agric. 3, 263—7.CrossRefGoogle Scholar
Asher, C. J., & Ozanne, P. G. (1967). Growth and potassium content of plants in solution cultures maintained at constant potassium concentrations. Soil Sci. 103, 155–61.CrossRefGoogle Scholar
Barber, S. A. (1962). A diffusion and mass flow concept of soil nutrient availability. Soil Sci. 93, 39–49.CrossRefGoogle Scholar
Barrow, N. J. (1966). Nutrient potential and capacity. II. Relationship between potassium potential and buffering capacity and supply of potassium to plants. 16, 61–76.Google Scholar
Barrow, N. J., Ozanne, P. G., & Shaw, T. C. (1965). Nutrient potential and capacity. I. The concepts of nutrient potential and capacity and their application to soil potassium and phosphorus. Aust. J. agric. Res. Aust. J. agric. Res. 17, 849–61.CrossRefGoogle Scholar
Beckett, P. H. T. (1964). Studies on soil potassium. I. Confirmation of the Ratio Law: measurement of potassium potential. J. Soil Sci. 15, 1—8.CrossRefGoogle Scholar
Black, C. A. (1968). Soil-Plant Relationships, chapter 9. New York: John Wiley and Sons, Inc.Google Scholar
Bray, R. H. (1954). A nutrient mobility concept of soil-plant relationships. Soil Sci. 78, 9–22.CrossRefGoogle Scholar
Carslaw, H. S. & Jaeger, J. C. (1959). Conduction of Heat in Solids, 2nd ed., p. 338. Oxford: Clarendon Press.Google Scholar
Drew, M. C., Nye, P. H. & Vaidyanathan, L. V. (1969). The supply of nutrient ions by diffusion to plant roots in soil. I. Absorption of potassium by cylindrical roots on onion and leek. Pl. Soil 29 (in the Press).Google Scholar
Drew, M. C., Vaidyanathan, L. V. & Nye, P. H. (1966). Can soil diffusion limit the uptake of potassium by plants? Int. Soc. Soil Sci. Trans., Commn. II and iv. Aberdeen, pp. 335–44.Google Scholar
Hagin, J. & Dovart, A. (1963). Note on methods for determination of available soil potassium. Emp. J. exp. Agric. 31, 186–8.Google Scholar
Loneragan, J. F. & Asher, C. J. (1967). Responses of plants to phosphate concentration in solution culture. II. Rate of phosphate absorption and its relation to growth. Soil Sci. 103, 311–18.CrossRefGoogle Scholar
Moss, P. (1963). Some aspects of cation status of soil moisture. I. The Ratio Law and soil moisture content. Pl. Soil. 18, 99–113.CrossRefGoogle Scholar
Nye, P. H. (1966). The effect of the nutrient intensity and buffering power of a soil, and the absorbing power, size and root hairs of a root on nutrient absorption by diffusion. Pl. Soil 25, 81–105.CrossRefGoogle Scholar
Rowell, D. L., Martin, M. W., & Nye, P. H. (1967). The measurement and mechanism of ion diffusion in soils. III. Tho effect of moisture content and soil solution concentration on the self-diffusion of ions in soils. J. Soil Sci. 18, 204–22.CrossRefGoogle Scholar
Salmon, R. C. (1964). Cation activity ratios in equilibrium soil solution and the availability of magnesium. Soil Sci. 98, 213–21.CrossRefGoogle Scholar
Talibudeen, O. & Dey, S. K. (1968). Potassium reserves in British soils. I. The Rothamsted classical experiments. J. agric. Sci., Camb. 71, 95–104.CrossRefGoogle Scholar
Tepe, W., & Leidenfrost, E. (1958). A comparison between plant physiological, kinetic and static values of soil analysis. I. Kinetics of soil ions as measured by means of ion exchangers. Landw. Forsch. 11, 217–19.Google Scholar
Tinker, P. B. H. (1964). Studies in soil potassium. IV. equilibrium cation activity ratios and responses to potassium fertilizer of Nigerian Oil Palms. J. Soil Sci. 15, 35–41.CrossRefGoogle Scholar
Ulrich, B. (1966). Cation exchange equilibria in soils. Z. Pfl. Ernähr. Düng. Bodenk. 113, 141–59.CrossRefGoogle Scholar
Vaidyanathan, L. V. & Nye, P. H. (1966). The measurement and mechanism of ion diffusion in soils. I. An exchange resin paper method for the measurement of diffusive flux and diffusion coefficients of nutrient ions in soils. J. Soil Sci. 17, 175–83.CrossRefGoogle Scholar
Vaidyanathan, L. V., Drew, M. C. & Nye, P. H. (1968). The measurement and mechanism of ion diffusion in soils. IV. The concentration dependence of diffusion coefficients of potassium in soils at a range of moisture levels and a method for the estimation of the differential diffusion coefficient at any concentration. J. Soil. Sci. 19, 94–107.CrossRefGoogle Scholar
Woodruff, C. M. (1955). The energies of replacement of calcium by potassium in soils. Proc. Soil Sci. Soc. Am. 19, 167–71.CrossRefGoogle Scholar