Authors: Doris Vetterlein Thomas Kühn Klaus Kaiser Reinhold Jahn
Publish Date: 2013/03/22
Volume: 371, Issue: 1-2, Pages: 267-279
Abstract
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 Xray diffraction and chemical measures of differently bound KWithin 49 and 98 days respectively 64 and 144 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 ‘nonexchangeable’ K extracted only 1/3 of the total K from illiteAndreas Rämmler and Jutta Fröhlich conducted the XRF analyses Christine Krenkewitz and Tina Truszezinski carried out clay fractionation chemical extractions and analyses of plant soil solution and soil samples Christine Herzlieb maintained the compartment system experiment We are grateful to the staff of the KleinAltendorf Research station and to the coordination team Timo Kautz Miriam Athmann of FOR 1320 at University of Bonn The study was funded by Deutsche Forschungsgemeinschaft research group FOR 1320
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