Soil Resources of Southern Siberia

Abstract

The article considers the issues of soil degradation and the possibility of conserving and restoring soil fertility in southern regions of Siberia. Long-term stationary research data is synthesized in order to determine the mechanism of erosion processes and obtain quantitative data on soil losses depending on key factors of water and wind erosion. Particular attention is given to the periodically extreme nature of processes that cause catastrophic soil degradation. Patterns of changes in the structure of processes that require agricultural soil conservation measures are revealed. The mechanism of soil erosion and soil degradation rate changes in the west to east direction along the belt of steppes and forest–steppes of southern Siberia. In the south of Western Siberia, the pressing issue is protecting soils from thawing erosion, in Khakassia the particular hazard is soil deflation, and in Cis-Baikal and Transbaikal region soil degradation is exacerbated by the combined effect of rainfall erosion and deflation. The results of a quantitative cartographic assessment of erosion hazard levels based on empirical models of potential soil loss and deflation are presented for the major agricultural regions with a case study of the Irkutsk–Cheremkhovo plain and the Nazarovskaya and Yuzhno-Minusinskaya depressions. A decrease in erosion soil losses as a result of socioeconomic agriculture reforms and a significant reduction in the area of agricultural land in the early 1990s and in the post-reform period (2010–2017) are noted. It is emphasized that the re-expansion of agricultural land observed in recent years creates the necessity of large-scale inventory mapping of erosion processes in southern Siberia. That data can be used to select an optimal nature management policy that promotes conservation of soil resources.