Saline soils of the Irkutsk region on large-scale soil maps

The aim of this work is a regional analysis of the areas of saline soils of different hydromorphism distribution in the Irkutsk region based on data from Rosgiprozem maps at a scale of 1 : 25,000 and explanatory notes to them for the period from 1964 to 2003. In the literature, data on saline soils in the region differ, which requires clarification using large-scale maps. For the first time, an analysis of the areas of saline soils of different hydromorphism in the districts of the Irkutsk region was carried out using 241 soil maps of Rosgiprozem on the scale of 1 : 25,000 and 265 explanatory notes to them. The analysis was carried out mainly on agricultural land. According to various sources, agricultural land occupies only 3.1–3.6% of the region’s area, while almost 90% of the region is under forest. According to maps and essays, saline soils are noted on area of 198.44 thousand hectares, which is 2–3 times higher than according to other sources. Saline soils are found in 27 of the 28 analyzed districts of the region, occupying from 1 to 19% of the surveyed farm area in different districts. The most widespread are hydromorphic saline soils, which are noted in 27 districts, semi-hydromorphic soils are less common – in 15 districts, and only in 7 ones automorphic varieties of saline soils are noted.