Premium
A comparison of the surface impedance factors of Ca, Na, Rb and Cs derived from their self‐diffusion coefficients in various soils
Author(s) -
STAUNTON S.
Publication year - 1990
Publication title -
journal of soil science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.244
H-Index - 111
eISSN - 1365-2389
pISSN - 0022-4588
DOI - 10.1111/j.1365-2389.1990.tb00233.x
Subject(s) - soil water , diffusion , chemistry , caesium , potassium , analytical chemistry (journal) , flux (metallurgy) , rubidium , phase (matter) , adsorption , mineralogy , extrapolation , thermodynamics , soil science , inorganic chemistry , environmental chemistry , geology , mathematical analysis , physics , mathematics , organic chemistry
SUMMARY Self‐diffusion coefficients of calcium, sodium, rubidium and caesium on the topsoils and subsoils of contrasting soil series are presented. The distribution ratios of each cation on each soil, at the moisture content of the diffusion experiments, have been calculated by extrapolation from series of suspensions. Diffusion coefficients were found in each case to be greater than expected by considering the liquid phase alone. Surface‐phase impedance factors, f s , were calculated. Although impedance factors are considerably smaller on the surface than in solution, the surface flux may exceed the flux in the liquid phase. Differences of an order of magnitude separated average values of f s for each cation. For a given cation, variations between soils were considerably less. No correlation was found between f s and soil mineralogy or composition. Values of f s were found to decrease with increasing distribution ratio. Reasons for this observation are discussed, in particular the energy of adsorption of the cations. The possibility of extrapolating these findings to other soils, to potassium and to other cations is discussed.