Restoration of Vegetation on Fallows in Krasnoyarsk Territory’s Forest Steppes

The species richness of the long-fallow lands in the Krasnoyarsk Territory’s forest-steppe zone includes 64 species of vascular plants from 50 genera and 19 families. Leading families of cenoflora are Leguminosae (10 species or 16%), Compositae (10 or 16%), Poaceae (9 or 14%) and Rosaceae (7 or 11%). The basis of the long-fallow lands flora were mesophytes (69%) with an insignificant participation of mesoxerophytes (17%) and mesohygrophytes (9%). Among the ecological-coenotic groups, species of meadow-forest forbs and grasses (34%), ruderal (22%) and forest-steppe (14%) species took the largest part. The aboveground phytomass of the grass cover depended on the age of the fallow (p < 0.001) and the density of the pine undergrowth (p < 0.05). Forb-brome fallows were the most productive among all in the forest-steppe zone (1.14 ± 0.11–2.02 ± 0.25 t ha^–1). Forb-gramineous fallows, experiencing a significant edificatory influence of Scots pine (Pinus sylvestris L.) (density of 29600 units ha^–1 in terms of large undergrowth), had the lowest aboveground phytomass (0.23 ± 0.06 t ha^–1). Fallow plots aged 7–18 years undergo rapid reforestation, with the density of Scots pine varying widely from 0.9 to 29.6 thousand units ha^–1 in terms of large undergrowth. It has been established that with an increase in the Scots pine density, the number of species, species diversity, species saturation, as well as the projective grass cover tend to decrease (p < 0.001).