Summary:

The paper presents an approach to the understanding of the structure and dynamics of mountain rivers which is primarily based on field research. Applicable methodologies have been developed at the Department of Geomorphology of the Jagiellonian University, Cracow. In studies of entire channel systems individual channels are divided into uniform reaches on the basis of their pattern as viewed on a map, and then investigated in the field with the use of specially designed survey forms. The forms cover five groups of data which are the identity of the channels, channel landforms, deposits, civil engineering structures and the characteristics of the drainage basins. The data collected provide insights into the rates of morphogenetic processes. Cartographic material, aerial photos and other information on the channels and their drainage basins should also be analysed in parallel with the field research. The channel parameters, landforms and bedload information, as well as calculated indicators on the channel reaches, provide the basis for a typology of channel reaches. A number of cases from selected research studies are discussed here. General patterns in the development of mountain river channels are also presented which are derived from studies of Carpathian and foreland rivers. These studies concluded that the channel systems had altered their structures. These alterations match changes occurring on the valley floor and valley slopes as a result of channel training, river impoundment and rock or gravel mining in the channels and land use changes in the drainage basin. River channel systems undergo vast changes as a result of such human impacts which mainly involve erosion-driven reshaping. This principally leads to the increased simplification and uniformity of the fluvial system structures. An overlap of the downcutting stimuli resulting from changes in the channels themselves and those resulting from land use change was noted after 1989.