|DOI / URL||link|
|Title (Primary)||Illite transformation and potassium release upon changes in composition of the rhizophere soil solution|
|Author||Vetterlein, D.; Kühn, T.; Kaiser, K.; Jahn, R.;|
|Journal||Plant and Soil|
|POF III (all)||T31;|
|Keywords||Exchangeable K; Non-exchangeable K; Subsoil; Illite; Soil solution; Ca|
|UFZ wide themes||RU1|
|Abstract||Aims and background Release of ‘non-exchangeable’ potassium (K) from interlayers of illite is diffusioncontrolled and has been shown to depend on the solution concentration of K and other cations (Ca2+, Mg2+, NH4+).
Methods We analysed changes in soil solution concentrations of K and competing cations in situ at
different distances from the root surface over time and related them to the transformation of illite, as
revealed by X-ray diffraction, and chemical measures of differently bound K.
Results and Conclusions Within 49 and 98 days, respectively, 6.4 and 14.4 % of the illite’s total K was
released upon contact with the root system. Mixed layered minerals increased from 33 (0 d) to 35 (49 d)
to 40 % (98 d). Release of K from interlayers and the transformation of illite occurred at soil solution K
concentrations close to the threshold of 80 μM suggested earlier. Concentrations of Ca and Mg increased with decreasing distance from the root surface, promoting the release of K. The NaBPh4 method
supposed to determine ‘non-exchangeable’ K extracted only 1/3 of the total K from illite.
|Persistent UFZ Identifier||http://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=13545|
|Vetterlein, D., Kühn, T., Kaiser, K., Jahn, R. (2013):
Illite transformation and potassium release upon changes in composition of the rhizophere soil solution
Plant Soil 371 (1-2), 267 - 279