The paper presents the results of an assessment of agroecological conditions in the soils of the Azov-Kuban lowland due to the development of technogenic degradation. A decrease in the share of initial chernozems due to water erosion (washed soils) in the Novokubansky district and waterlogging (compacted and fused soils) in the Timashevsky district and the city of Krasnodar was revealed. A noticeable increase in density in hydrometamorphized analogues of chernoz.

The work presents the observational data of soil cover structure dynamics, changes in soil composition and properties under the influence of anthropogenic impact. A decrease of 6.0-7.4% in the share of black soils (Chernozem) over 50 years of observations and a corresponding increase in the area of waterlogged soils associated with closed depressions have been revealed. Due to the high dynamism of soil density with changes in its moisture content, a criterion has been sought to characterize this dependence and a method has been proposed to describe it using dynamic curves. The amplitude of density fluctuations and its dependence on the severity of anthropogenic degradation – 59 -78% – has been established. Correlation analysis confirmed a medium strength relationship (determination coefficient 0.39-0.42) between shrinkage and specific surface area of initial degradation soils and a strong relationship (determination coefficient 0.79-0.86) in meadow-chernozem compacted soils. A strong correlation has been found between the volumetric shrinkage and fines content in the size distribution (determination coefficient 0.84-0.96). A new diagnostic criterion (“T” criterion) for the intensity of hydrometamorphism and, in general, for the physical aspect of anthropogenic soil degradation has been proposed.

This work reviews the relation of the grain-size distribution and impact of the use of rice rotation soils on the main agrophysical indicators of soils that determine the composition and properties of soil cover of modern delta of Kuban. The regularities of dependence between the density of the matrix soil and the grain-size distribution that consist of mineral composition of alluvial soils and rocks have been identified. The trend towards increase in soil density with increase in physical clay and silt content, as well as increase in matrix soil density has been established. No significant differences in agrophysical properties of subsurface soil horizons and underlying formations have been identified. The agrophysical indicators of soils of rice fields and boharic analogues during their agricultural use have been assessed. The hydromorphic soil-forming processes did not lead to considerable changes in agrophysical properties of alluvial formations and soils involved in rice rotation.

Southern chernozem soils of the Taman Peninsula were studied to assess their suitability for viniculture and examine the possibility to dispose winery waste by diluting it with water and subsequently applying it to the soil. The subjects of this study were southern chernozem soils and the composition of the wine and brandy distillery stillage. Southern chernozem soils feature high levels of density (1.29–1.64 g/cm 3 ), alkalinity (pH 8.0–8.5), and saturation of the soil adsorption complex with calcium (69.6–73.2%), magnesium (17.0–18.9%), and sodium (7.3–11.5%). The effects of various concentrations of wine and brandy distillery stillage on the chemical properties of the soil, qualitative and quantitative composition of its fungal flora, and soil fatigue degree were assessed. In the laboratory environment, the composting of soil with the undiluted winery and distillery waste significantly alters the soil reaction (by 0.1 pH units in comparison with the control) and the organic matter content (the difference from the control is 0.21%). Three fungi genera constitute a opportunistically pathogenic group in the soil samples: Fusarium spр . , Cephallosporium spр . , and Alternaria spр . Fungi belonging to the genus Fusarium predominate in the soil samples; their share reaches 54.5% of the total amount of isolated micromycetes.

Under description is a profile configuration represented by stratified bowllike morphostructures with the increased thickness of darkgray humus horizons and diaperlike morphostructures consisted of the olive-brown material ascending from the lower horizons in Vertisols developed on the bottom of a huge closed depression (padi) in Eisk peninsula. Histograms are presented to show statistic distribution and non-parametric statistic indices for morphometric characteristics of the above morphostructures. The statistic relationship between the morphometric indices is estimated. Under discussion is also the genesis of such morphostructures in Vertisols.

The soils shown on Russian soil maps of the Kuban-Azov Lowland under the names of slitic (vertic) and compacted soils contain diagnostic features characteristic of the type of dark slitozems and subtypes of slitic soils in the new Russian soil classification system, or Vertisols and Vertic soils in the WRB system. These are slickensides, wedge-shaped structure, clayey texture through the entire soil profile, and shrinkage cracks formed during soil drying. It was found that dark quasi-gley slitozems (Vertisols) occur in the central parts of the bottoms of large (> 1.5 km along the longest axis) closed depressions. Humus quasi-gley slitozems (Vertic Stagnic Phaeozems (Clayic, Pachic)) are confined to the peripheral parts of the bottoms of these depressions and to the bottoms of smaller (0.8–1.5 km) closed depressions. Deeply slitic humus—quasi-gley soils and deeply slitic clay-illuvial chernozems (Bathyvertic Stagnic Phaeozems (Clayic, Pachic)), in which the upper boundary of slickensides is found at the depths from 100 to 200 cm, usually occur in the bottoms of closed depressions with the longest axis of less than 0.6–0.8 km and in the bottoms and on slopes of shallow flat-bottomed ravines. With respect to the distribution of Vertisols and Vertic soils, the Kuban-Azov Lowland can be subdivided into eight soil districts. In five of them, these soils occupy from 0.1% to 12.1% of the territory.

В почвах Кубано-Приазовской низменности, которые на почвенных картах выделены под названием “слитые” и “уплотненные”, установлено наличие диагностических признаков, используемых для идентификации типа темных слитых почв и подтипов слитизированных почв по классификации почв России, а также реферативной почвенной группе (РПГ) Vertisols и почв других групп с главным квалификатором (principal qualifier) Vertic по WRB: поверхностей скольжения (сликенсайдов) и клиновидной структуры на фоне глинистого гранулометрического состава всего почвенного профиля и образования трещин усадки при высыхании. Установлено, что темные слитые квазиглеевые почвы (Vertisols по WRB) встречаются в центральной части днища обширных (длина большой оси более 1.5 км) замкнутых понижений (падей). Гумусово-квазиглеевые слитизированные почвы (Vertic Stagnic Phaeozems (Clayic, Pachic)) приурочены к периферии днищ падей и к днищам замкнутых понижений с длиной большой оси 0.8–1.5 км. Гумусово-квазиглеевые глубокослитизированные почвы и черноземы глинисто-иллювиальные глубокослитизированные (Bathyvertic Stagnic Phaeozems (Clayic, Pachic)), в которых верхняя граница появления поверхностей скольжения (сликенсайдов) наблюдается на глубине от 100 до 200 см, обычно встречаются по периферии замкнутых понижений среднего размера, в днищах замкнутых понижений с длиной большой оси менее 0.6–0.8 км и в днищах и на склонах неглубоких балок. На Кубано-Приазовской низменности выделено 8 почвенных районов по распространению вертисолей и вертиковых почв. В пяти из них указанные почвы занимают от 0.1 до 12.1% площади района.

The current state and rate of hydromorphism development in the soils of flat bottomed depressions in Western Ciscaucasia are assessed. The dynamics of the soil cover pattern on a plain with numerous mesoand microdepressions and on a watershed with weakly pronounced erosion relief were revealed. The relationship between the expansion of the waterlogged areas and the pattern of the soil cover of the agrolandscapes in the depressions was revealed. The dependence of the areas of excessively moistened sites on the changes in the topography was shown. The direction and parameters of the changes in the morphology, chemical composition, and hydrological properties of the degraded hydromorphic soils were investigated. The relationships between the density of the soils and the humus content and the composition of the exchangeable bases were studied. Methods for the assessment of the rates of the degradation processes based on the comparison of aerial photographs and soil maps for typical sites in the territory investigated are proposed. The specific features of decoding the aerial photographs of the soils in the depressions were revealed. The relations between the differences in the photos’ tone and the degree of the hydromorphic degradation of the soils were found. Promising methods for interpretation of aerial photographs with the help of image analysis programs can be recommended.