“Black soils” in the Russian Soil Classification system, the US Soil Taxonomy and the WRB: Quantitative correlation and implications for pedodiversity assessment

“Black soils” recently proposed by the FAO Global Soil Partnership, include fertile soils, characterized a thick, dark-colored soil horizon rich in organic matter. This study addressed concept of “black soils”, terms taxonomic relationship their corresponding types existing classifications. Similarity studies were based on calculation distances between selected groups with matter–enriched horizons Russian Classification System, United States Taxonomy and World Reference Base for Resources. In process, we used so called ”centroids”, which are calculated mean values several properties each using legacy data derived from national international databases. The results indicated that Great Groups Mollisol Order US had small within order, except some soils shallow depth to hardpan or permafrost. Dark-colored Vertisols Andisols found differ Mollisols similar environments mainly under grasslands. We recommend excluding cluster due peculiarity properties, potential use management. While completely dissimilar WRB Vertisol group dark-humus compact fitted well cluster, presumably different studied system. classification short distance Base. Also, similarity was high all Kastanozems, but places not interpreted pedogeographic point view. ascribed phenomenon geographical bias Though form distinct roughly corresponds Taxonomy, may be significant, contributing pedodiversity soilscapes soils”.