Quantification of the areas of saline and solonetzic soils in the Ural Federal Region of the Russian federation

Abstract

Soil Salinization Map of Russia on a scale of 1: 2500000 (the paper version) has been used for compiling an electronic map of the Ural Federal Region and an attribute database containing twelve characteristics of soil salinization. The areas of saline soils have been quantified for the entire region and its administrative districts. The total area of saline soils in the 0- to 200-cm layer averages up to 6.85 million ha or 5.53% of the plains in the region. The area of soilssaline in the 0- to 100-cm layer averages up to 4.91 million ha, including 4.13 million ha of weakly solonchakous soils (84%) and 0.78 million ha of solonchakous ones (16%). More than half of them (58.3%) are assigned to the moderately and strongly saline soils. The soils saline in the 0- to 100-cm layer are characterized by the neutral salinization type (45%) or the types of soda salinization and neutral salinization with soda (55%). The areas of the region with saline soils are dominated by solonetzic microassociations. The average area of the solonetzes is about 3 million ha. The area of solonchaks is about 0.09 million ha. The area of saline soils is the greatest in Kurgan oblast and the lowest in Sverdlovsk oblast and the Yamal-Nenets autonomous okrug. The formation of saline soils in the Ural Federal Region is related to the climatic conditions of the steppe zone with insufficient moistening and lithologicgeomorphologic conditions (saline Paleogene-Neogene deposits and poor drainage of the area).