Abstract
The use of synthetic ion-exchange resins as buffers of nutrient ions is a potential mechanism for the control of ion concentrations in nutrient solutions. In this study equilibrium constants for two cation exchange resins and three anion exchange resins were determined at 25°C in low ionic strength systems. The measured constants were used to successfully predict the resin combinations required to achieve desired solution equilibrium concentrations. The effectiveness of these resins in buffering solution ion concentrations was evaluated by examining their release characteristics in circulating systems from which aliquots of solution were withdrawn and replaced with deionised water to simulate plant uptake. Buffering of NO3 and SO4 concentrations was effective when manual control of one anion was imposed. The cation resins were ineffective in buffering the concentrations of Ca and Mg with a tendency for the resins to retain most of the Ca and Mg in adsorbed form.
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References
Arnon D I and Grossenbacher K A 1947 Soil Sci. 63, 159–182.
Checkai R T, Hendrickson L L, Corey R B and Helmke P A 1987 Plant and Soil 99, 321–324.
Converse C D, Gammon N and Sayer J D 1943 Plant Physiol. 18, 114–121.
Hendrickson L L, Turner M A and Corey R B 1982 Anal. Chem. 54, 1633–1637.
Reichenberg D 1966 In Ion Exchange Vol. 1 pp 227–276. Marcel Dekker, INC, New York.
Schlenker F S 1942 Soil Sci. 54, 247–251.
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Kerven, G.L., Asher, C.J. & Dethlefs, L. Release characteristics of ion-exchange resins as buffers in low ionic strength nutrient solutions. Plant Soil 155, 239–242 (1993). https://doi.org/10.1007/BF00025028
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DOI: https://doi.org/10.1007/BF00025028