Modern Transformation Factors for Floodplain-Channel Complexes in the Upper Angara Region

Аннотация

This paper focuses on identifying adverse processes of relief formation by ascertaining the transformation mechanisms of floodplain-channel complexes for different types of economic impact. Within the lower reaches if a number of tributaries of the upper reach of the Angara river, the specific features in the modern functioning of valley geosystems undergoing long-term industrial development are considered, based on observations made during 2015–2018. We carried out a landscape-geomorphological analysis of the key areas to identify the main types of channels as well as the most widely occurring landscape complexes within them. A retrospective analysis of the intensification process of environmental management covering a period longer than 350 years identified dominant agricultural activities which we designated as the main transformation factors of valley geosystems. The analysis revealed the mechanisms by which production activities influence the landscapes of floodplain-channel complexes as well as the main relief-forming processes whose intensification is due to the construction and operation of the facilities of the economic infrastructure. Two variants of the conditions for the functioning of the floodplain-channel complexes in the zones of anthropogenic impact are considered. The first variant includes areas with intensive industrial exploitation of the natural resource potential within which there occurs complete or partial destruction of the floodplain-channel complexes accompanied by the manifestation of adverse exogenous processes. Characteristic for the second variant of development of the valley complexes is a minimization of the risks of the manifestation of hazardous relief-formation processes by carrying out environmental measures and constructing engineering protection facilities in the course of gradual long-term development.