Digital Mapping of Soil Associations and Eroded Soils (Prokhorovskii District, Belgorod Oblast)

A new method of digital mapping of the soil cover pattern with calculation of the share of soils of different taxa and degree classes for soil erosion in the soil associations is proposed. A comparative analysis of soil maps obtained using different methods of construction (visual expert and digital) and with their different contents (displaying the dominant soil or soil associations) has been performed. In the case of mapping by the visual expert method (with the display of the dominant soil), a significant underestimation of the total area of moderately and strongly eroded soils in comparison with the digital mapping is noted. These differences are due to the underestimation of the area of small polygons with moderately and strongly eroded soils in the composition of soil associations on slopes of low steepness and in shallow hollows in the visual expert method of mapping. When the content of digital maps is generalized from soil associations to dominant soil categories, a significant change in information on the degree of soil degradation by erosion is also noted. Comparison of visual expert and digital methods for mapping soils of different taxa indicates a high degree of compliance between the spatial location and area of soil delineations with similar component content in both cases. The greatest differences between the soil maps created by these methods are noted for the soils with periodic overmoistening, namely, meadow-chernozemic (Luvic Chernic Phaeozem (Oxyaquic)) and chernozemic-meadow (Luvic Stagnic Chernic Phaeozem) soils because of the poor consideration for microtopography in traditional mapping. In general, it can be concluded that the creation of a digital map is more difficult in terms of the need to use specialized computer programs and mathematical models. However, the resulting digital databases contain information of a higher level of detail than traditional soil maps.