Due to the natural conditions, forest-steppe mires, more than those of the taiga zone, are confined to specific landforms, the distribution of which has certain patterns. Extensive research that evenly covered the entire forest-steppe zone of European Russia revealed that the floodplains of large and medium-size rivers had the greatest degree of paludification, while the flatlands above the floodplains have many small mires in the valleys of small rivers and enclosed depressions of varying genesis. Fens and swamps are widespread, transitional mires and raised bogs are confined to suffosion, aeolian and karst basins on terraces above floodplains, aqueoglacial and Paleogene plains.