Soil Cover Diversity and Its Spatial Organization at Different Map Scales

We summarized the results of studies of pedodiversity and contrast and variability of soil properties based on the analyses of soil maps of different scales for the republics of Karelia and Dagestan and the Moscow region. We used fragments of the Soil Map of the Russian Federation on a scale of 1 : 2 500 000 as a small-scale map and three different medium-scale maps (from 1 : 300 000 to 1 : 500 000). Large-scale maps (1 : 10 000) were compiled for representative plots within the studied territories specifically for the study of pedodiversity. All the maps were digitized, map legends were converted to the new Russian soil classification system and to the World Reference Base for Soil Resources (WRB), and Shannon–Wiener diversity indices were calculated. Comparison of indicators revealed the dependence of the values of the diversity indices on the map scale. The indicators for the large-scale map were relatively low and did not differ much when using Russian and international classification. We concluded that for the successful assessment of soil diversity at different scales, it is important to use several large-scale maps that reflect the heterogeneity of regional soilscapes. Natural boundaries between soilscapes and soil regions can be found using the pedodiversity index map. In almost all cases, maps with a WRB-based legend had lower indicators of pedodiversity than maps with a legend based on the Russian soil classification. This confirms the fact that the international classification is less detailed than the Russian national classification, which was originally intended for large-scale mapping of soils.