Modern Land Use of the Osa River Basin (Upper Angara Region)

The territory of the Osa river basin was studied, where under the steppe and forest-steppe vegetation types of soils are common that are not typical for the taiga zone: real chernozems with a relatively thick humus layer, sometimes reaching 45-50 cm, dark humus soils and other types of fertile soils. It has been established that hydrometamorphosed chernozems with a thickness of the humus horizon of more than 1 m are widespread in low relief areas, under conditions of increased moisture. a series of expeditions was carried out to study the soils of natural, arable and fallow lands, as well as pastures. The content of humus and the granulometric composition of soils were determined (types of natural soils: gray typical, hydrometamorphosed chernozem, thin chernozem, typical dark humus; types of agrogenic analogues of natural soils: typical agroabrazem, dark agrozem, typical agrogrey, agroserohumus typical, agrodark humus typical, hydrometamorphosed agrochernozem, typical agrochernozem; more than 30 samples). The influence of these indicators on soil fertility is considered. The change in the nature of land use in the period from 1983 to 2013 has been studied, and possible reasons for these changes. A map of modern land use in 2021 was made. A comparison was made of the nature of modern land use with their use in 1983, 1997, 2005, 2013.