The contact angle of wetting as an integral indicator of physical-chemical properties of chernozems of Kamennaya steppe

The sessile drop method was used to measure the contact angle of wetting (CA) of ordinary Chernozem from the fields of the Kamennaya Steppe agrolandscape used in various ways. The treatments differ in the intensity of tillage operations (protected mowed steppe, arable land after moldboard plowing), the use of mineral fertilizers and their aftereffect, as well as changes in soil properties under the influence of irrigation. At the same time, the total organic carbon content, C/N ratio, specific surface area, and rheological parameters were determined for the physical and chemical characteristics of soils. The results of the study showed that the hydrophilic-hydrophobic properties of the surface of the solid phase of soils, which largely determine the main structure-forming properties of soils, can be characterized by the value of the wetting edge angle. The CA of the studied soil samples varies from 32 degrees (highest wettability) to 45 degrees (lowest wettability). The lowest wettability is due to the increased content of hydrophobic compounds in the organic matter of soils and is characterized by the highest CA and is typical for native, untreated soil of the mowed steppe, which differs from other studied variants of the experiment in all explored physical and chemical parameters...