Efficiency of Different Conditioner Compositions Formulated for Improving Physicochemical Characteristics of Calcareous Saline-Sodic Soils

Abstract

ABSTRACT The saline and sodic nature of the soil is considered a major plant growth-limiting factor in many agricultural regions. In this experiment, three soil amendments containing sodium polyphosphate, lignosulfonate, amino acid, polyethylene glycol and different ratios (w:w) of H2SO4 to citric acid, i.e.,, 0:9 (CF1), 3:6 (CF2), and 3:3 (CF3) were provided and their efficiency in improvement of soil characteristics was evaluated. The amendments were added into the leaching water at application rates of 0, 1000, 2000, and 3000 L ha−1 at four stages. The final soil ECe values indicated the effective leaching of the salts from the soil columns for both amendments and the control. All the amendments decreased soil ESP with less effectiveness at the higher application rates. The CF1 and CF2 at the low to medium application rates (1000 and 2000 L ha−1) effectively increased soil hydraulic conductivity (HA) over the control while they were ineffective at the highest application level (3000 L ha−1). The increase of the HA was accompanied with a significant decrease in the dispersible clay and an increase in the available water content. Soil penetration resistance was also lower in the soils treated with the CF1 and CF2 at the application rates of 1000 and 2000 L ha−1. According to the results, CF1 and particularly CF2 at the application rate of 1000 L ha−1 might be recommended for improving physical properties of saline-sodic soils, although further studies particularly under field conditions are needed.