NATURAL CHORICAL RIVER LANDSCAPES AND BASIN GEOSYSTEMS (A CHORICAL-REGIONAL MODEL OF THE LANDSCAPE STRUCTURE OF RIVER BASIN DISTRICTS)

Abstract

The article examines the methodological and procedural foundations for developing a hydromorphological chorical-regional model of the landscape organization of river basin systems and river basin districts. The relevance of the study is determined by the contemporary need to integrate river basin water resources management with landscape and spatial planning, which is especially important under conditions of increasing anthropogenic pressure and the need to harmonize management decisions with the natural hierarchy of river geosystems. The starting point of the study is the understanding that river landscapes are hydromorphological in nature, are formed through the functioning of the flow-channel system, and should be analyzed with due regard to the poliscale and cross-scale organization of landscapes. The paper provides a review and comparative analysis of the approaches developed by Ukrainian scholars to physical-geographical and geomorphological regionalization, and clarifies the relationship between the regional, chorical, and topical levels in the study of river basin systems. Particular attention is paid to the role of the geomorphological framework, especially erosional-accumulative relief, which determines the spatial organization of river valleys, basins, and associated landscape complexes. It is shown that, in order to substantiate the chorical-regional model, it is necessary to combine the general hierarchy of landscapes with the order-based hierarchy of river basin systems and the paragenetic hierarchy of river-valley landscapes. It is substantiated that river basin systems of the first four orders mainly belong to the chorical level; however, their identification cannot be purely formal and should be carried out with regard to the position of such systems within geomorphological regions and subregions. At the transition to the regional level, river valleys acquire key importance as paragenetically organized landscape systems. The use of paragenetic taxonomy makes it possible to distinguish the territorial structure of valley-river landscapes, in particular the young river landscape formed by contemporary channels and floodplains. In this context, it is shown that the belt of the paragenetic river landscape corresponds to the regional level, whereas sectors and links belong to the chorical level and provide a more detailed interpretation of the internal structure of river valleys. The proposed approach makes it possible to integrate basin and landscape planning, to consider river basin districts as a combination of chorical river basin systems and regional valley sections, and also to refine the scientific understanding of small rivers through their connection with the chorical level of organization. The developed model may be used as a theoretical and methodological basis for hydromorphological studies, territoria l analysis of river landscapes, and the preparation of management decisions in the field of water protection and the sustainable use of water resources.