Digital soil mapping of erosion-induced degradation of Chernozems on the East-European Plain

Abstract

Soil erosion remains a pressing problem especially on the Chernozems, since these soils are the most fertile and agriculturally used. The paper presents an analysis of soil erosion rates, land use history, soil properties and the state of the soil cover in 6 key sites of 10 thousand hectares each, located in different parts of the Chernozem belt on the East European Plain. The maps of erosion-induced degradation of Chernozems were constructed using field and laboratory data in >1600 soil survey points by two Digital Soil Mapping (DSM) methods: “Statistical” and “Modelling”. The area of eroded soils obtained by two DSM methods differs by up to 5 times. The maps constructed by the “Modelling” DSM are in good agreement with literary data and have a logical shape and location of eroded soils and sediments patterns. The results demonstrate the prospects for further development of DSM using simulation erosion models. “Statistical” DSM should be tested in areas with high soil erosion rates and in the presence of pronounced micro relief. The share of moderately and severely eroded soils varies greatly at different sites – from 1 % to 28 %. The extent of degradation of Chernozems depends on the rates of soil erosion and duration of plowing. The share of eroded soils on the Central Russian Upland is 14–28 % according to “Modelling” DSM. This region needs significant soil conservation measures. The erosion rates and duration of plowing is relatively low on the Oka-Don Lowland and Bugulmino-Belebeevskaya Upland, the share of eroded soils on the studied sites is only 1–2 %. Soil sediments occupy 7–10 % of arable land and are confined to numerous micro-depressions of the relief.