Evaluation of the Nature of Erosion Resistance in Forest-Steppe Chernozems

Progressive degradation of cultivated soils due to the development of wind and water erosion processes is one of the main unresolved problems of chernozem development. The investigations were conducted to clarify the nature of erosion resistance of chernozems and to find new methods for its diagnostics based on the use of innovative soil physics methods. The work was carried out during an expedition to Voronezh oblast (Ostrogozhskii and Talovskii raions) in 2024 and subsequent laboratory experiments. The objects of the study were ordinary arable agrochernozems and (for comparison) ordinary chernozems under the oak grove of the Kamennaya Steppe federal nature preserve. Modern innovative methods of studying the structural state of the soil (using laser diffractometer, vibratory sieve shaker, analytical set for determining the texture characteristics of dispersed systems, contact angle, micromorphology, IR spectrometry methods, and analysis of the isotopic composition of carbon) made it possible to clarify the nature of the erosion resistance of chernozems. The latter is governed not only by the content of the silt fraction and humus but also by the microstructural state of the soil, the values of electrical conductivity of the soil solution, and the content of carbonates. Extra plowing (underlying deeper layers) and degradation of carbonates from the parent rock against the background of homogenization of mineral mass and organic matter leads to alkalization of the soil solution per unit of pH and disintegration of structural separates by 20–30%. An increase in the external specific surface area for nitrogen by 3–4 m2/g and the total specific surface area for water by ten times, and a decrease in the contact angles of wetting by ten degrees diagnosed a decrease in the microaggregation of ordinary chernozem during plowing up. The plowing reduced the electrical conductivity of the soil solution and humus content in the plow layer to one half and led to a 10% loss of agronomically valuable aggregates in melkozem (fine earth). An increase in a value of the stable carbon isotope ratio to the total amount of the element by 4–9‰ indicates anthropogenic “steppification” of landscapes.