Irina Vladimirovna Agurova

Th e purpose of this work was to study the acidity of degraded agricultural soils. Th e main objectives of the research
were to study the actual and potential soil acidity of agricultural lands of the Donetsk Peoples Republic on the example
of agricultural farms in the northern part of the Shakhtyorsky district. It was established that the studied model sites
are characterized by a slightly acidic, neutral or slightly alkaline medium reaction, which creates favorable conditions
for the formation of crops and plant growth. When studying the exchangeable acidity of soils, the ambiguity
of changes in its values was established, depending on the location of the model sites, the system of soil content in
the crop rotation, the horizon, and other factors. The most exceeding the control values of the exchange acidity are
characteristic of the slope surfaces of sites where the intensity of erosion processes reaches a maximum (exceeding
the indicator compared to the control by average of 8,6%). In the future, increased values of exchangeable acidity
may adversely aff ect the formation of crop yields. Changes in the values of hydrolytic acidity of soils follow the same
regularity as the variation in the indices of exchangeable acidity. The most signifi cant excess of the hydrolytic acidity
index in comparison with the control was recorded on the slope sites of the fi elds (increase by 11–17%). The conducted
studies confi rm the need for constant agroecological monitoring of these lands with the regulation of mineral
fertilizers to increase the absorption capacity of soils due to increased values of exchangeable and hydrolytic acidity.

The purpose of this work was to study the absorption capacity of degraded soils of agricultural land (using the ex- ample of agricultural farms in the southern part of the Shakhtersky district of the Donetsk People’s Republic). The main objectives of the research included studying the amount of exchangeable bases, exchangeable calcium and exchangeable magnesium. To study the soil cover of agricultural lands, model sites of varying degrees of degradation were selected. When choosing them, factors such as the prevalence of the type of disturbance within the study site, the degree of anthropogenic transformation, and the type of cultivated crop were taken into account. Soil sampling was carried out in September 2023. It was found that the most significant decrease in the amount of exchangeable bases was recorded in areas left fallow after growing a number of crops — sunflower, corn and wheat. The values of the sum of exchangeable bases were reduced compared to the control by 56–85%. The indicators of exchangeable calcium in the soils of the studied agrocenoses varied fr om 5,5 to 38,08 mEq×100 g-1 of soil, which depended on the position of the site in the landscape, the link in the crop rotation system, and the type of crop being cultivated. The lack of a proper soil care system in the studied areas affected the content of exchangeable calcium, reducing its content by an average of 42,7–84,8%. The percentage of magnesium from the total exchangeable bases ranged from 14,3 to 20,6%. The most significant decrease in the content of exchangeable calcium and magnesium in relation to the control was recorded in sites after sunflower cultivation, as well as in areas left fallow, wh ere the combined effect of a number of unfavorable factors (sloping surface, predecessor crop with an increased level of removal of mineral nutrition elements) influenced the change this indicator.