Erosion patterns on cultivated and reforested hillslopes in Moscow region, Russia

The severity of accelerated erosion is affected by tillage practices, slope gradient, shape, and length. Our hypothesis is that fly ash, the product of high temperature coal combustion, magnetic minerals, magnetic susceptibility, and organic C content of a soil can be used to estimate the extent of soil loss as a result of human activities. The objectives of the current study near Pushkino, Russia were: (i) to determine the extent and local variability of soil removal from a hillslope because of accelerated erosion using closely spaced duplicate transects, and (ii) to determine subsequent deposition of sediments on a lower landscape position using the presence, depth distribution, and concentration of fly ash, magnetic minerals, organic C, and magnetic susceptibility. The study was done by comparing the amount of fly ash contained in soil profiles at different landscape positions of a cultivated site with that at a reforested site planted to spruce [Picea abies (L.) Karst] trees similar to60 to 80 yr ago. Deposition of fly ash derived from distant railway traffic started in or about 1851 and increased in 1870 because of construction of a closer railway. Considering the whole transect, the cultivated site had 12% less fly ash in the upper 20-cm soil layer as compared with the reforested site. The fly-ash results indicated that only 2.4 cm or 12% of the upper soil layer has been removed from the hillslope because of accelerated erosion associated with the last 60 to 80 yr of cultivation. Deposition of sediment rich in fly ash on the lower and upper footslopes suggests accelerated erosion has occurred at the cultivated site.