The contact angle (α) varies nonlinearly with the soil water content (θg) in water-repellent soils; however, a quantitative description of such a θg dependence of α is still lacking. Using a dimensionality reduction technique such as dynamic factor analysis (DFA), we managed to identify two common patterns within a scattered data set of α vs. θg measurements performed with the molarity of an ethanol droplet test in 16 soil samples. These two common patterns, derived from the DFA, provided the basis for calibrating a proposed empirical, three-parameter, linear model that described satisfactorily (R2 > 0.89) an additional α–θg data set used for model validation, from 40 soil samples with organic matter contents spanning from 110 to 650 g kg−1. This offered both scaling and a flexible quantitative description of the soil water content dependence of water repellency.

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