Natural Conditions and Ecological Potential of Geosystems in the Central Part of the Oka Plateau (Eastern Sayan)

The objective of this study is to make an analysis of the natural characteristics of the mountain territories in Southern Siberia as part of the development of the technique for assessing the ecological potential of geosystems by using the central part of the Oka Plateau as an example. A brief description of the relief and exogenous processes is provided for three geomorphological regions: Okinsko-Sorokskii, Okinsko-Tustukskii and Soroksko-Bel’skii, which are characterized by a predominance of flat-topped interfluves, slopes of moderate steepness and deeply incised river valleys. The main features of the climate and hydrological regime in the study area are emphasized. The first ever bathymetrical survey of Lake Sagan-Nur was made, and its morphometric indicators were calculated. On the basis of the morphology and bottom sediments of the lake basin, the genesis of the lake is treated as glaciotectonic. The chemical composition of the waters and the lake bottom sediments were determined, which may well characterize it as a natural unpolluted reservoir. The natural regionalization scheme for the southeastern part of Eastern Sayan is presented. The large-scale landscape map has been compiled for a portion of the central part of the plateau as well as indicating and the main species of vegetation within its boundaries. The identified features in the natural conditions of the study area (relief, climate, surface waters and landscapes) furnish a means of assessing the ecological potential of geosystems. A combination of the nature- and anthropocentric approaches in assessing the ecological potential of geosystems offers considerable scope for optimal use of natural and human resources of this area which sparsely populated but rich in mineral resources. On the plateau, a detailed study of landscapes and their components is crucial to the assessment of the ecological potential of geosystems, although forecasts of the possible enhancement in the influence of the anthropogenic factor and analysis of the consequences of such an influence on the natural environment are also required.