Structure and productivity of herbaceous plant communities of the Krasnoyarsk forest-steppe
Section: Monitoring of natural and anthropogenically disturbed areas
Forest-steppes zone was often regarded as a passing zone between the forest and steppe types. However, floristic studies conducted in recent years made it possible to identify the forest-steppe as an independent type with characteristic structural features of vegetation cover. On the example of secondary by origin herbaceous plant communities of the Krasnoyarsk forest-steppe (the South of Middle Siberia, left Bank of the Yenisei river, 56°35´12´´N, 93°01´20´´E), their structural organization and dynamics of accumulation of aboveground phytomass during the growing season are shown. The formation of grass stand depends on the type and intensity of anthropogenic influence. On the territory of the research, the zonal upland meadow of the Bromus inermis (Leyss) Holub + heteroherbae association was identified as the leading plant community. On the southern slopes, the meadow-steppe Stipa pennata L. + heteroherbae association is noted. The analysis of the species composition of the study area showed that almost the whole territory belongs to long-fallow lands of the late recovery stage. It is indicated by the dominance of the terminal species of meadow steppes Bromus inermis, as well as the absence of weed species among the dominants. At the beginning of September, due to active development of high grasses in the upland meadow, the maximum productivity of green and dry mass for the season is formed, which is 224.8 and 111.9 g/m2, respectively. In the feather grass meadow steppe, the maximum productivity 338 g/m2 was recorded in June. The structure of phytomass is simple. The predominant botanical groups are cereals and various grasses. Introduction of forest species (Anemone sylvestris L.) and shrubs (Rosa acicularis Lindl.) indicates the restoration of zonal vegetation, as by decrease of the anthropogenic pressure, conditions for formation of productive meadow communities, and for further reforestation, occur.
Keywords: forest-steppe; productivity; species composition; phytomass structure