Active and exchangeable cations in soils
- 1 January 1985
- journal article
- research article
- Published by CSIRO Publishing in Soil Research
- Vol. 23 (2) , 195-209
- https://doi.org/10.1071/sr9850195
Abstract
The amounts of cations, Ca, Mg, K and Na, that could be extracted from soils by salt solutions varied with the cations, anions, acidity or alkalinity, and solvent of the extracting reagent. The variations were largest for soils that contained organic matter as the main source of those cations, and smallest in clay soils with little organic content. Calcium was the cation most affected and sodium the least affected. It appeared that the extractants removed all diffuse double-layer exchangeable cations, and variable portions of the other active cations including inner-sphere cations, specifically adsorbed cations, and those chelated by organic materials. A moderate, non-specific extractant containing a quaternary ammonium salt, choline chloride, is recommended for the displacement of exchangeable cations with a minimum contribution from other active cations. For an estimate of all forms of active cations, e.g. for soil nutrient assessment, a solution of ammonium sulfate is suggested.Keywords
This publication has 8 references indexed in Scilit:
- EFFECT OF CHLORIDE AND SULFATE ANIONS ON THE CHEMICAL CHARACTERISTICS OF SOME ACID SOILSCanadian Journal of Soil Science, 1982
- Concentration and pH Dependence of Calcium and Zinc Adsorption by Iron Hydrous Oxide GelSoil Science Society of America Journal, 1982
- Effects of pH and aluminosilicate composition on KMg exchange selectivity of amorphous aluminosilicatesGeoderma, 1981
- The Operational Definition of the Zero Point of Charge in SoilsSoil Science Society of America Journal, 1981
- Ion adsorption mechanisms in oxidic soils; implications for point of zero charge determinationsGeoderma, 1980
- Exchange Capacity of Calcium and Sodium Soils as Determined by Different Replacing CationsSoil Science Society of America Journal, 1977
- The determination of exchangeable calcium and magnesium in carbonate soils.Australian Journal of Agricultural Research, 1954
- Studies in pedogenesis in NSW. 5. The Euchrozems.Australian Journal of Agricultural Research, 1953