In Russia, the irrigation was advanced especially in 1987-1988 and the total area of irrigated soils reached 5.75 million ha (2.7% of the country's agricultural land). The major objects of irrigation are situated in the region along the Volga River and in the North Caucasus; they are distributed between the steppe (35%) and the dry steppe and semidesert (31.4%) zones. In the south of Russia, the areas occupied by initially saline soils in complex with solonetzes were included into those to be irrigated. In 1988, 76% of the agricultural area proved under irrigation by sprinkling. Drainage was provided only in a small area (15.7%), thus provoking the rise of the groundwater level, secondary hydromorphism, soil salinization and sodification. About 10% of lands were irrigated by saline waters (>1 g/l). The low quality of irrigation waters is typical for the regions, in which small rivers, ponds and reservoirs with local runoff serve as the source for irrigation. In some cases, industrial waste and agricultural chemicals polluted the irrigation waters.

In 1988, the irrigated soils underwent the following degradation processes: irrigation erosion (8.9% of the total area under irrigation), soil compaction and dehumification (13.4%), salinization (16.5%), to say nothing of the secondary salinity, because this process was inherited from initially saline and alkaline soils occupied 8% of the total area under irrigation. In the North Caucasus, the irrigated soils also suffered from the waterlogging.

In view of the changing economic situation in Russia, the total area of irrigated soils has decreased by the early XXI century by 16%, including 8.1% in the North Caucasus and 4% in the Volga region. The area of saline soils and solonetzes under irrigation also declined (by 7.8 and 15%, respectively). The portion of the irrigated lands with the groundwater level <3 m and their salinity >1 g/l has decreased due to their exclusion from the agricultural lands. However, the recent state of irrigated soils in Russia shows no improvement. The above degradation processes remain in the soils for a long period. Thus, in the Volga region, the salt-affected soils even without irrigation contain soluble salts for decades in spite of a considerable decrease in the groundwater level.

At present, the control over the ecological status of irrigated lands has considerably changed to the worse. The current land monitoring system does not provide adequate information, which makes it impossible to give an objective assessment of soil degradation processes in irrigated lands and in the adjacent landscapes affected by irrigation.

This study was supported by the Russian Foundation for Basic Research, project no. 04-04-48197.