| Autor: |
Dufey, Joseph E., Sheta, Tarek H., Gobran, Georges R., Laudelout, Henri |
| Zdroj: |
Soil Science Society of America Journal; January 1982, Vol. 46 Issue: 1 p47-50, 4p |
| Abstrakt: |
A sand‐clay soil mixture was equilibrated in a column with various NaCl‐CaCl2solutions at constant normality (0.03N). After each equilibration, the percolating solution was labeled successively with 36Cl, 22Na, and 45Ca. The breakthrough curves of the radioactive species made it possible to calculate both effective pore volume and, at a given Darcy velocity, the Peclet number (P) for each ion. PClwas found to decrease markedly when the exchangeable sodium percentage (ESP) increased from 0 to about 20%. PNaand PCawere almost not affected by changing ESP. The following sequence was observed: PCa< PNa< PCl. The discriminatory mixing power of soil towards the three ions likely results from changing size of montmorillonite tactoids and from demixing of adsorbed Na and Ca cations. |
| Databáze: |
Supplemental Index |
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