Premium
SELF‐DIFFUSION OF IONS IN SOIL
Author(s) -
GRAHAMBRYCE I. J.
Publication year - 1963
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.1365-2389.1963.tb00945.x
Subject(s) - ion , diffusion , tracer , chemistry , adsorption , phosphate , soil water , phosphorus , radioactive tracer , inorganic chemistry , environmental chemistry , soil science , geology , thermodynamics , organic chemistry , physics , nuclear physics
Summary Self‐diffusion coefficients for I ‐ and H 2 PO ‐ 4 in soils have been measured by determining the movement of radioactive tracers of these ions from a cylindrical section of labelled soil to a similar section initially without tracer. D I varied with the composition of the equilibrium soil solution used, both concentration and nature of cation affecting the value. These results may be explained by variations in the extent of negative adsorption of diffusing anions in the presence of negatively charged soil particles, and the consequent variation in the size of pore from which the anions are excluded. Phosphate diffusion was measured in the natural soil. The low values of D H 2 PO 4 are attributed to adsorption and fixation of phosphate ions. Results obtained using different methods of phosphorus extraction and treatments designed to investigate effects of microbial activity are discussed.