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The soils shown on Russian soil maps of the Kuban-Azov Lowland under the names of slitic (ver tic) 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 bot tomed 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.

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The aim of the article is to submit data about ground water table and soil salinity of the rice irrigated systems at the Sivash seashore in Nyzhnegorsky district of Crimea in 2017–2018 which is 4–5 years from irrigation cease. It was found that many soil cover patterns with salt-affected solonetz at the rice system were leached from salts to the depth about 3–3.5 m by flooding irrigation during half a century. In 2017–2018 ground water tables were deeper than the critical depth. Ground water mineralization is characterized by mosaic spatial distribution, varying from 1.9 to 7.4 g/l with a tendency to growth as ground water depth increases. Depression funnel of ground water table was formed at the seashore. The bottom water drive is up to 0.8–1.6 m relatively sea level. The first symptoms of the salinity returning in grounds of vadose zone were found: (1) appearance of calcium and magnesium chlorides in pore solutions of formally no saline or weakly saline horizons; (2) increasing trend of sodium and chloride ion activity measured in pastes with moisture 50% (w) at the dynamic plots in 2018 as compared with 2017; (3) frequency of grounds with clustered gypsum crystals is increased.

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