Possibilities of using the Landau–Deryagin law to evaluate soil degradation as a result of its contamination with chlorides

Abstract

The contamination of heavy loamy chernozem by iron, sodium, magnesium, calcium, and hydrogen chlorides (2% of soil mass) decreases soil moisture content (W, percent of soil mass) in the interval of the soil moisture pressure (Р) from 0.0 to–0.6 atm, which indicate soil degradation. In a range of P from–0.2 to–0.6 atm, there is a close correlation between the logarithm of Р module (log|P|) and W and, therefore, a regression relationship log|P_W| = |P₀|–kW, where |P₀| and k are empirically determined parameters. This relationship is similar to the Landau–Deryagin law. The parameters |P₀| and k are also in a close correlation, which is described by the regression equation |P₀| = 29.3k–0.557. At chernozem contamination by chlorides, the |P₀| and k parameters become smaller, and so they may be used for the evaluation of degradation of chloride-contaminated soils.