Sodium Displacement in Saline Soils Measured by a Non-destructive Method PDF

Keywords

loam, clay, sodium

Abstract

Leaching of sodium was investigated in columns of loam and clay saline soils in relation to different methods and initial water content. Non-destructive measurement for the distribution of the applied radio sodium was made during the leaching course by gamma spectrometry. The results indicated that the method of leaching appeared the most important factor in altering the Na distribution. Based on the magnitude of the Na peak displacement with respect to water applied, the efficiency methods in leaching of the loam soil followed the order: simulated rain (SR) > continuous ponding (CP)> intermittent ponding (IP) at air dry and CP> SR>IP at both field capacity and near saturation initial water content. The results were reserved in the clay soil. Pre-wetting the loam soil slowed down the movement of sodium. In the clay soil, no consistent effect on Na movement occurred with increasing initial water content. The efficiency in displacement was explained on the basis of the effective fraction of water participating in solute transport.