Soil degradation is considered one of the biggest threats to the balanced management of soil resources and is a unique challenge for the sustainable development of society, exacerbating problems of both ecological and socioeconomic nature. In the system of scientific research, soil degradation as a result of irrational land use is one of the most urgent problems of soil science, ecology, and agriculture. Special attention is paid to the current state of arable chernozems, which is related to their productivity and important economic importance for the food security of the country. The Prydnisterska upland is considered to be a region with significant natural resource potential and, in particular, fertile soils, the basis of which are chernozems. The structure of the upland soil cover is dominated by chernozems, which reaches an area of 406 thousand hectares (62 % of the territory of the upland), of which typical chernozems account for 260 thousand hectares (39 %), and podzolised chernozems have an area of 146 thousand hectares (23 %). The current state of the chernozems of the Prydnisterska upland, as well as Ukraine in general, is causing increasing concern due to the intensification of degradation processes. The literature sources analysis and generalized comparisons of the arable chernozems properties show that over the past 40–50 years, the most threatening degradation processes in the region have been: dehumidification, erosion of the chernozem humus horizon, soil compaction in field crop rotations, especially on arable land, which results in the structural destruction. The situation is also complicated by the dominance of the sloping topography in the structure of cultivated areas, which, under conditions of periodic torrential rainfall and neglect of anti-erosion measures, undergo increased degradation. The involvement of chernozems in agricultural production under conditions of organic matter deficit has led to dehumidification. Over the last century, the humus content in the chernozems of the Prydnisterska upland has dropped from 5–6 % to 3– 4 %. The results of the research indicate a noticeable degree of dehumidification within the arable horizon (0–20 cm), which increases with changes in the morphometric parameters of the relief and due to the intensity of erosion processes. The obtained values of Ctc:Cfc indicate the dominance of humate type of humus in automorphic conditions and a smooth change from humate to fulvatehumate type of humus within the slopes. The results of colorimetry identified changes in the natural color of chernozems, the intensity of which increases with the intensification of degradation processes. According to the color difference index (∆E), which takes into account the visual perception of color by an observer, the chernozems of slopes with a steepness of more than 3° were clearly discolored. According to the content of agronomically valuable air-dry aggregates, structure density, and porosity used as diagnostic criteria, different degrees of compaction and disintegration were found at the level of arable and sub-arable horizons of chernozems of watershed plateaus and slope relief. The research results show that there are no chernozems with a critical degree of physical degradation. Under automorphic conditions, chernozems are characterized by a low, rarely medium degree of disintegration and compaction. Within the sloping terrain, the degree of physical degradation of chernozems is assessed as mostly severe. The obtained results highlight the peculiarities of arable soil transformation under modern soil management conditions, in particular, their morphological features, as well as physical and physicochemical properties. The main content of the work is aimed at studying the degradation processes, their peculiarities of manifestation, intensity and direction in the chernozems of the Prydnisterska upland at the catenary level, taking into account the geomorphological conditions of the territory.
