Agrophysical properties of black soils depending on types of economic use in the Krasnoyarsk forest-steppe

About 50% of the world’s distribution of the richest soils on the planet, black soil, is concentrated in Russia. On black soil, 75% of the gross output of grain crops and 50% of livestock production are manufactured. However, the current state of black soils causes concerns about the increasing degradation that threatens Russia’s food security. Black soils are a subject to significant anthropogenic stress; first of all they are exposed to agricultural impact. The problem of degradation of arable black soils is largely due to the deterioration of agrophysical properties and the degree of degradation varies in different soil-climatic zones. The granulometric compositions, density of soil structure, general porosity and water permeability depend on the nature of the soil use. Throughout the entire range of the studied agrophysical soils properties, arable black soils are inferior to virgin analogues located in similar conditions of the landscape. Post-irrigative soils transformed into a set aside are inferior in their agrophysical properties to virgin analogue, but surpass arable soils in some indicators. The range of unfavourable properties of black soils acquired as a result of irrigation is quite wide and manifests itself at almost all levels of their structural organization. It should be noted that irrigation with ecologically safe irrigation norms of 300 m3 / ha does not impair the physical properties of the soil, in contrast to heavy irrigation norms, that determine the unidirectional and noticeable expression of the main indicators in the direction of their deterioration.