ASSESSMENT OF THE QUALITY AND USE OF THE LANDS OF THE UPPER ANGARA REGION WITH ACCOUNT FOR A NEW INTEGRAL INDEX OF SOIL FERTILITY

Abstract

Based on the results of studies carried out in 2023-2024, the use of soil and the level of soil fertility in the agricultural areas of Cheremkhovsky District of Irkutsk Region are characterized. Agricultural lans make 21% of the total area of the District. About half of the lands is not used. Despite favorable climatic conditions the soils of the major part of the territory under study are not more than satisfactory (sometimes unsatisfactory or poor and rarely good) according to such agrochemical and agrophysical indicators as soil density and the contents of physical clay, humus, nitrates, agriculturally valuable aggregates, mobile phosphorus, and potassium. Soil condition is excellent in the native territories not impacted by human economic activities. According to soil density and the contents of physical clay and agriculturally valuable aggregates, the soils are mostly unsatisfactory and poor, mainly because of rocks, for being used in crops growing. Agrotechnical interventions are warranted. Soils of the arable lands near settlements should be treated with mineral potash- and phosphorus-containing, less often with nitrogen-containing mineral or organic fertilizers. A reserve of agricultural lands for use is represented by abandoned lands, but they also need agrochemical, agrotechnical and other interventions, since the soils have not yet recovered enough.