Eine Methode zur Bestimmung austauschbarer Kationen in Waldböden

A Method for the Determination of Exchangeable Cations in Forest Soils A simple extraction method with NH₄Cl was developed for determining exchangeable cations in forest soils. The influence of selected parameters (reaction time, concentration of NH₄Cl, filter medium etc.) affecting the amount of extractable cations was tested and a standardisation was done. The cation exchange was completed in less than 4 h. For a quantitative extraction of K, Mg, Ca, and Mn a concentration of 0.05 M NH₄Cl was sufficient. The extractable amount of these cations was always clearly defined. However, extracted Al and Fe increased with the NH₄Cl-concentration. Depending on the soil samples, the exchange is not quantitative even when using a saturated solution. The extractable H⁺ is nearly independent of the NH₄Cl-concentration. Probably considerable amounts are dissociated from organic acids. The optimized method is feasible and can be used for K, Mg, Ca, and Mn as an alternative to percolation methods.