Calculation of the Morphometric Characteristics of the River Basin Relief of High and Low Plains Based on a Digital Elevation Model

The article presents the results of a comparative morphometric analysis of the river basin relief, conducted on the basis of a digital elevation model (DEM) using the QGIS 3 and SAGA GIS 9 geoinformation applications. The aim of the work was to compare the degree of erosion risks in the river basins of the high and low plains. The objects of digital modeling and calculations were the Polnoy Voronezh and Chembar river basins. The first basin is located on the Oka-Don lowland plain with a relatively flat relief, the second is significantly dissected and is located within the Volga Upland. A hypsometric map was constructed and the distribution of the surface area of the basins by absolute height was shown. For the rivers Polnoy Voronezh, Chembar and their tributaries with a catchment area of more than 50 km2, the most significant morphometric variables were calculated: the shape and slope of the longitudinal profile, river fall, the depth of dissection and the average gradient of catchment slopes. The Polnoy Voronezh river basin is characterized by low risks of erosion development due to small values of dissection depth, average slopes of watercourses and catchment slopes. In the Chembar river basin, morphometric variables express a significant risk of erosion development, especially in catchment areas with an average gradient of slopes of more than 2°. Based on the principles of basin nature management, the obtained quantitative data on the relief can be useful for carrying out balance calculations of liquid and solid runoff movement within catchment areas, developing projects for soil and water protection measures, and improving the structure of land use.