Influence of electrolyte concentration, sodium adsorption ratio and cation combinations on relative saturated hydraulic conductivity of saline soil

Abstract

Soil hydraulic conductivity (K) is an important parameter in the transport of water and salts in the soils. This study was performed to determine the influence of water quality parameters flowing through the soil on the relative saturated hydraulic conductivity (rKs) of salt affected soil. Its aim was to examine the effect of electrolyte concentration at different SAR (sodium adsorption ratio) values of Na-Ca and Na-Mg leaching solutions on changes in rKs of saline soil. The experiments were conducted under laboratory conditions in packed soil columns with saline soil from the Jatov locality, Slovakia. The leaching solutions at SAR values of 5, 10, 20, 30, 40 and at the concentrations of Na-Ca and Na-Mg binary electrolytes of 20, 40, 60, 100 and 120 mmol l -1 were used. The concentration and composition of the water flowing through the soil showed a significant influence on relative saturated hydraulic conductivity of the soil used in the experiments. The results of the measurements indicated a decrease in rKs by gradually decreasing the electrolyte concentration and with increasing SAR values of the percolating electrolytes of both cationic pair Na-Ca and Na-Mg. The laboratory experiments also showed that the values of rKs of the soil measured with Na-Ca solutions were higher than those measured with Na-Mg solutions.