ИСТИНА

The Russian Plain can be divided onto two parts in relation of agricultural activity. The northern half of the plain is predominantly taiga zone with extremely high proportion of forested area and very limited areas of arable fields. The southern half of the Russian Plain is located in the zones of broad-leaf forests, forest-steppe and steppe and it is characterized by high proportion of arable lands with period of intensive cultivation from 300–350 years in broad-leaf landscape zone up to about one century on the south-east of steppe zone. It is one of the main agricul-tural regions of Russia with relatively high rates of sheet, rill and gully erosion. However considerable land use transformation in combination with climate changes during last 25–30 years influenced on the soil erosion rates in different parts of studied area. Complex approach is applied for assessment of recent trends of sheet, rill and gully erosion in different landscape zones of the area. It is included application of remote-sensing and GIS spatial analy-sis methods for evaluation erosion rates for vast areas (total area, transect and the key small river basins) for dif-ferent time slices, erosion model calculations and a set of field methods for quantification of sediment redistribu-tion rates within key sites. Investigation is undertaken in 6 selected transects (area of each transect is about 10–12 thousand km2), uniformly distributed over the area of the Russian Plain. There are three main factors which are responsible for possible variation of erosion rates: climate changes, land use transformation and crop rotation modification. Contribution of each from above mentioned factors on erosion rate trend changes considerably de-pending from landscape zone.