Soil Erosion and Small River Aggradation in Russia

Abstract: Intensive soil erosion lead to transformation of sediment redistribution within river basin, because of increase of sediment input from slope to the river channel. Cultivation of interfluve and valley slopes within temperate climatic zone promotes to development sheet, rill and gully erosion. Intensive growth of cultivation area in Russia began from the southern part of forest zone and the northern part of forest-steppe zone in XVII century. Than area of intensive cultivation expanded in south and south-east directions and the rest of forest-steppe zone and steppe zone were ploughed during XVIII—XIX century. As a rule both rill and gully erosion rates increased dramatically immediately after cultivation, because of growth of surface runoff. From the other hand part of underground water decreased, that influenced on the summer water discharges of small rivers. Both these tendencies in connection with possible climatic fluctuations of precipitation across the agricultural part of Russia resulted in small river aggradation. Dynamic of small river aggradation were studied for different parts of agricultural zone of Russia using method of comparison of topographical maps composed for different time intervals. In addition the detail study of soil redistribution within small basins was undertaken for few key sites located in different landscape zone. Different methods and approaches wer