Artificial Forest Stands’ Impact on Soils’ Biological Activity in Khakassian Steppes

Artificial afforestation is especially important for dry steppe regions, where forests perform complex soil-protective, climate-forming, health-improving and aesthetic functions. Therefore, in 1975–1978 in the Shirinskaya dry steppe of the Republic of Khakassia on the premises of the Sukachev’s Institute of Forestry, several experimental artificial multispecific plantations of tree and shrub species were created. The studies were carried out in ten biodendrogroups (BDG) of the Shirinskaya steppe. For comparison, a site of a virgin natural steppe phytocenosis, located in close proximity, was taken. The purpose of these studies was to study the influence of tree and shrub vegetation on the edaphic conditions change, the ground cover succession, and the change in the soil functioning regime. The maximum positive effect on the biogenic indicators functional activity is exerted by BDG with edificatory coniferous species, under the crowns of which subordinate shrubs with a sufficient amount of leaves develop. Artificial forest plantations contribute to the formation of litter and an increase in the micromycetes’ proportion. A correlation was established between abiotic factors, especially illumination, and the growth of terrestrial herbaceous phytomass. Changes in ecological and phytocenotic factors contribute to an increase in biological diversity by optimizing the phytomass reserves and structure, and the emergence of new herbaceous vegetation types. Thus, ecologically stable artificial forest biocenoses can form under the dry steppe conditions.