Zoning of Catchments of Small Rivers in the South of the Volga Upland by the Water Protection Role of Forests

The article presents the results of the spatial distribution analysis of protective forest plantations within the catchment basins of in the south of the Volga Upland (within the Volgograd region). The data obtained are important for planning agroforestry and land reclamation. The interpretation of 133 reservoirs using satellite images and large-scale (Scale – 1:100 000) isolinear mapping of forest cover in the key areas allowed us to find that for the majority of catchments the low forest cover of the central part of the basin, caused by agricultural land use, is typical. The main environment protection function is performed by large forests of natural (growing in floodplains, uplands and steppe ravines) and artificial origin (forest shelterbelts), localized near the source (in watersheds) and the mouths of small rivers. Depending on the type of plantations and their presence or absence near the source or mouth of the river 6 types of forest cover of catchments in the south of the Volga Upland have been identified: I – river source and mouth have maxima (relative to the rest of the catchment basin) of natural forest cover; II – the source has a maximum of artificial forest cover, the mouth has a maximum of natural forest cover; III – there are no plantations at the source, there is a maximum of natural forest cover at the mouth; IV – there is a maximum of natural forest cover at the source, there are no plantations at the mouth; V – there is a maximum of artificial forest cover at the source, there are no plantations at the mouth; VI – there are no plantations at the source and mouth. It is found that the largest area within the south of the Volga upland is occupied by catchments of the III type (38.3 %), the relief of which is characterized by the predominance of gentle slopes, which have been exposed to the greatest extent to plowing and destruction of natural forest vegetation. Together with catchments of the IV–VI types, having no afforestation in the lower stream, about 59.2 % of plantations of the south of the Volga Upland are not protected from the processes of water erosion and deflation.