Tm. Skene et Jm. Oades, THE EFFECTS OF SODIUM ADSORPTION RATIO AND ELECTROLYTE CONCENTRATION ON WATER-QUALITY - LABORATORY STUDIES, Soil science, 159(1), 1995, pp. 65-73
The effects of solution sodium adsorption ratio (SAR) and total electr
olyte concentration (TEC) on the release of total organic carbon (TOC)
, total N and total P, and clay dispersion from three soils were studi
ed in the laboratory. Solutions with high SARs and low TECs caused the
greatest amount of clay dispersion, and these highly turbid solutions
also had high concentrations of TOC and total P. Positive correlation
s were obtained between turbidity and TOC, turbidity and total P, and
TOC and total P. Total N was positively correlated with turbidity and
TOC for one of the soils studied, but not for the other soil for which
these measurements were made. It follows from these results that SAR
and TEC also have a significant influence on TOC and total P concentra
tions. Field data of other workers show similar relationships between
these water quality factors. Decreasing the SAR and/or increasing the
TEC of a solution in contact with soil will decrease the concentration
s of organic carbon and total P released and decrease clay dispersion.
For some soils, the concentration of N in solution may also decrease.
Increasing salt concentrations substantially is not desirable, but a
decrease in SAR can be achieved through the use of calcium compounds a
nd their application to soils in a field situation may help to improve
water quality.