Mapping and forecasting of changes of eroded soils (Central-chernozem region of Russia)

Abstract

The paper presents assessment of the current state and risk of soil degradation of arable land (area ~800 sq. km.) from erosion. The rates of soil erosion were calculated by the WATEM/SEDEM. The obtained rates of soil erosion were converted into erosion losses of the soil profile and compared with the current thickness of the humus horizons (according to field survey data). The calculated and actual (according to the field survey) soil losses correspond to each other. The rate of soil erosion in the southern section is almost twice higher than in the northern section, however, the difference in the area of eroded soils is 4.4 times higher. The forecast was calculated for each pixel with respect to the current thickness of the humus horizons. With the stable rate of erosion in the next 50 years, the area of eroded soils will almost double on the studied territory, and in 200 years will grow almost 3 times relative to the current state. After 200 years of plowing without soil protection measures, the share of eroded soils in the northern section will only reach the current level of soil degradation in the southern section, while the share of eroded soils on south section will reach almost 35%. These results clearly demonstrate that the areas of priority application of soil conservation measures should be determined not by the rate of erosion, but by the rate of degradation of the soil cover from erosion.