RESEARCH ON ACIDIC PROPERTIES OF GRAY FOREST SOILS

The research was carried out at the Department of Agriculture, Soil Science and Agrochemistry of Vinnytsia National Agrarian University, which made it possible to use the existing educational and laboratory base and conduct observations during 2022–2024, obtaining representative data to assess the dynamics of changes in the main agrochemical indicators. Studies have shown that growing winter wheat and soybeans causes changes in the acidity of the soil solution, which reflects the impact of crops on the chemical properties of the agroecosystem. Analysis of soil agrochemical parameters showed that the soil under winter wheat was characterized by increased acidity (lower pH) compared to other crop rotation options, which may be a consequence of physiological processes of nutrient absorption by the root system and microbiological activity in the rhizosphere zone. This trend is consistent with the literature, where a decrease in soil pH is often recorded for wheat crops during the growing season, which is associated with biochemical changes and the removal of nutrients by plants (pHKCl 4.6±0.07) and exceeds the optimal values for this crop. It was established that such a level of acidity potentially slows down plant growth, reduces the availability of essential nutrients and negatively affects the activity of beneficial soil microflora. Hydrolytic acidity (Hg) was 3.27±0.09 mg-eq/100g of soil, which further emphasizes the need for agrotechnical measures. In areas with soybeans, the soil pH was higher – 5.6±0.06, which is closer to the optimal. The generalization of the data allows us to note that the cultivation of winter wheat and soybeans has different effects on soil acidity indicators. Winter wheat demonstrates greater sensitivity to increased acidity and the presence of mobile aluminum, which can limit its productivity. Soybeans, on the contrary, are grown under more favorable pH conditions and lower concentrations of mobile aluminum, which ensures more stable physiological activity of plants and the formation of a high-quality harvest. The results of the study emphasize the importance of regular monitoring of soil acidity and the use of agrotechnical measures to regulate it. Practical results can be tested to develop recommendations for crop selection and agrotechnologies in different soil and climatic conditions, aimed at maintaining soil fertility and sustainable agricultural production.