Аннотация:We studied spatial variation of the thickness of soil horizons (litter, A, E, and B) at three sites in southern and central Karelia, each having an area of 15–20 km2. The re-sults were obtained from a detailed (1:10 000) soil survey of the sites. The variability of the horizons’ thickness increased in the sequence B-O-E-A. For mapping purposes, indicator kriging was found to be more effective. It allows generating probability maps (maps of the probability of soil horizons’ existence, in our case). We performed indica-tor kriging at the three sites for O, A, E, and B horizons. The shift in the zones of the horizons’ presence/absence occurs mainly at distances of 700–900 m. In all the sites surveyed only the litter layer and the B horizon have continuous distribution, while the A and E horizons are represented by numerous polygons of various sizes. We found that a similar spatial arrangement of different soil horizons indicates low pedodiversity of the area. Ordinary kriging was used for estimating variability of soil horizons’ thickness. In disturbed forests, the spatial coherence of forest litter thickness is low, in-creasing with recuperation of the community and reaching a maximum in old-growth spruce forest. A horizon thickness at the Gomselga site (the only one in which the hori-zon is present continuously) shows a "nested structure". At Gabselga site (which has large areas of the E horizon present), the thickness of the E and B horizons shows peri-odic distribution. The period for the B horizon thickness is twice as much as for the E horizon. We explain the phenomena by higher "sensitivity" of the podzolic horizon thickness to soil forming factors (mesorelief) compared to the B horizon, wherefore lower intermediate morainic ridges affected the thickness of the E, but not the B horizon.