Soil Potassium Reactions as Related to Clay Mineralogy of Selected Kentucky Soils1
- M. G. Cook and
- T. B. Hutcheson2
Clay mineralogy was related to soil K reactions of Heitt, Eden and Maddox series, representative soils of high K-supplying power; and Maury, Bedford and Tilsit series, representative soils of low to medium K-supplying power.
Clay fractions of Heitt, Eden and Maddox soils contained more illite than Maury, Bedford and Tilsit clay fractions; thus illite is the probable seat of K-supplying power.
Effects of drying the soils on exchangeable K levels were investigated. Upon drying, fixation was observed when the initial, field-moist level of exchangeable K was relatively high; release occurred when the initial level was low.
The 14Å. vermiculite spacing contained by soils of high K-supplying power was easily collapsed to 10Å. by K saturation and 100° C. heating, whereas that spacing of soils of low K-supplying power was affected little by K saturation, requiring 300° C. or higher heating for closure. At least two possible explanations could account for the differences in collapsibility: (a) differences in magnitude, location and origin of interlayer charge; and (b) presence or absence of nonexchangeable Al in interlayer positions.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © .