Original experimental data on the chemical structure of homogeneous components of organic matter (OM) of waterproof macroaggregates of typical chernozem of different land use variants were obtained, which allowed to clarify the relationship between the molecular composition of OM and the water resistance of the soil structure. It is shown that a rapid deterioration in the qualitative composition of OM of virgin chernozem under anthropogenic impact, in particular an increase of its hydrophobicity and aromaticity degree, reduces the potentiality of particles to cohesion, resulting in a sharp decline in the water resistance in Haplic Chernozem. The proportion of water-stable macroaggregates 2-1 mm in size in the composition of air-dry aggregates of the same size in Haplic Chernozems decreases sharply: 35 times (arable land option) and almost 300 times (permanent bare fallow option) compared to that in the steppe.
Artemyeva et al. (Thu,) studied this question.