Diagnosis of human-induced degradation of soils of the Azov-Cuban lowland

Abstract

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.

Mycological composition of soils in Kuban rice agrocenoses as a biotic component for their health

“…These are indirect signs of changes in mineralogical composition of soils, increase in their composition of minerals of montmorillonite group, which give the properties mentioned above to soils and underlying rocks. These changes are most intense in the 4 to 6 year period of rice soil use [9,11].…”

“…This, in turn, affected their water-physical, physicochemical, and biological properties. These transformations were reflected in morphological features: colouring, new formations, structure, profile structure and even granulometric composition [6,11]. At the same time, taking into account the specificity and radical changes that occur in the soils of rice agrocenoses, the term 'rice type' is added to the name of genetic type at the regional level [1].…”