Cation exchange
Under the cation exchange refers to the exchange of on the surface of soil particles or colloids bound cations with in the soil solution dissolved cations. Clay minerals , humic substances , some iron and aluminum - containing minerals have negative charges to which cations in the soil water can loosely bind and thus, for example, prevent nutrients from being washed out. The cation exchange thus enables a dynamic equilibrium between the cations of the soil solution and negatively charged soil particles, with a cation being bound more strongly to a negatively charged particle surface, the higher its value . The measure of the ability to exchange cations is the cation exchange capacity .
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- ^ Fritz Scheffer, Paul Schachtschabel : Textbook of soil science . 14th edition. Spectrum, Heidelberg 1998.