Remote assessment of factors of spatial differentiation of the Volga delta soil cover
Keywords:the Volga delta, geoinformational analysis, soil and vegetation cover structure, salinization, soil degradation
The results of mapping of the soil cover according to data provided by remote sensing of Earth in the area of the steppe bordering ilmens, located westward of the Volga delta are presented in the article. The Western Ilmen-hill plain is generally shaped by changing moisture conditions as the main landscape-forming factor. In the process the changes are associated with both natural and anthropogenic processes. The article implements an algorithm that allows automated identification of spatial boundaries of soil contours, which are characterized by indicative signs displayed in various thematic layers. Satellite imagery from LANDSAT 5-8, SENTINEL-2 satellites provided by Earth Explorer data portal were used in the studies. The interpretation of the satellite images to determine the extent of soil salinizationand to calculate the NDSI index was carried out during periods when the surface was devoid of vegetation. The remote assessment of the spatial differentiation of the soil cover was carried out by means of a cross-spectrum analysis of the quantitative parameters of soil, vegetation and terrain obtained in the process of field, analytical and remote studies. The analysis of schematic maps of the halurgic soil degradation showed a sudden increase in the salt concentration and soil halurgationin the western part of the Volga in the period from 2010 to 2019 that was caused by changes in the hydrological conditions of the Volga River and road and rail routes usage.