Spatial and Temporal Transformation of Geosystems of the Baikal Rift Zone Depressions

Abstract

The purpose of the study is to identify the features of spatial and temporal transformation of geosystems of the Baikal rift zone depressions. Materials and methods. The research is based on the data of fi eld route observations, analysis of thematic maps, results of expert interpretation of satellite images, generalization of literary sources using historical, landscape and comparative-geographical methods, GIS. Results and discussion. The functioning of the geosystems of the study area is determined by a number of factors: material-energy exchange, development, internal and external interrelationships, resonance, and sustainability. Endogenous factors have a spatial-diff erentiating eff ect practically at all structural-hierarchical levels of geosystems and are through natural agents controlling the whole system of intercomponent interactions. Transformations under the infl uence of climatic and endogenous factors occurred synchronously and caused the manifestation of resonance phenomena that stimulated the spatial and temporal transformation of geosystems. Seismicity, volcanism, heat fl ows, and hydrothermal processes are associated with active faults in rift depressions; faults "control" sedimentation and the position of river valleys. Along fault zones, upward fl ows of heated and decompacted mantle matter create widespread heat fl ows that directly aff ect both the components of geosystems and the spatial and temporal transformation of geosystems as a whole.Conclusions. The change of material-energy exchange of geosystem with its environment due to endogenous component is one of the main factors of formation of specifi city of transformation of geosystems of the Baikal rift zone depressions. The most intensive transformation was subjected to the areas of impact of plumes, mantle fl uids, development of magmatic and metamorphic rocks, and major faults. The combination of diverse geodynamic regimes of continental riftogenesis and mountain formation caused an ambiguous response of geosystems to climate change, which determined the development of dark coniferous taiga, waterlogged larch sparse forests with cedar shrub and sub-taiga light coniferous geosystems in the study area.