The article presents the material on the species composition and biological productivity of grass ecosystems along the catena to Lake Utichye on the territory of the Iuso-Shirin steppe of Khakasia. Describs pattern of below-ground and above-ground components in stepр ecosystems 30% of the living phytomass is located in the soil and no then 60 % is allocated in below-ground organs. The productivity of the steppes varies depending on the type of ecosystem. In the ecosystem of the desert steppe, the vegetation cover has a minimum number of species, aboveground phytomass, a maximum number of underground organs, and the fraction of dead roots prevails, up to 50%. The richer and more humid ecosystems, the greater the diversity of species in the vegetation cover, the more reserves of aboveground phytomass and living underground organs. Dead root stocks are reduced to 20-35%.
