Keywords: ordinary chernozem; luvic chernozem; soil organic matter; sand; silt; clay; slopes of northern and southern exposures

Abstract Modern processes of climate change are accompanied by a number of negative factors, which include aridization, desertification, soil degradation and erosion. The research was were carried out on the territory that is the southern border of the distribution of the late glacial phase of the Dnieper glaciation (Middle Pleistocene, 100–230 thousand years ago). The influence of forest ecosystems on the aggregate composition and water stability of soil aggregates, the features of which determine the protection of soils from erosion and other degradation processes in semiarid conditions, was assessed. It has been established that luvic chernozems of forest ecosystems are characterized by an increased content of aggregates of fractions 2–3, 1–2 and 0.5–1.0 mm, as well as water-stable aggregates of fractions > 5, 0.5–1.0 and 0.25–0.5 mm in the 0–20 cm layer compared to ordinary chernozems of steppe ecosystems. The content of soil organic matter is a determining factor on which the aggregate composition and content of water-stable aggregates in luvic chernozems of forest ecosystems depends. The existence of close direct relationships has been established between the content of soil organic matter and the content of aggregates of the 0.5–1.0 mm fraction, as well as between the content of soil organic matter and the content of water-stable aggregates of fractions 3–5, 2–3 and 1–2 mm in chernozems of steppe and forest ecosystems. The existence of close direct relationships between the sand content and the content of water-stable aggregates of fractions 3–5 and 2–3 mm was revealed. The established increase in the content of soil organic matter and sand in luvic chernozems of forest ecosystems compared to ordinary chernozems of steppe ecosystems is the reason for the improvement in the aggregate composition and the increase in the content of water-stable aggregates. This is a key aspect of increasing the resistance of soils in forest ecosystems to various negative factors, such as desertification, degradation, wind and water soil erosion.

Bamutaze, Y., Meadows, M. E., Mwanjalolo, M., & Musinguzi, P. (2021). Effect of land use systems and topographical attributes on the condition of surface soil physicochemical properties in a highland catchment of the Lake Victoria Basin, Uganda. Catena, 203, 105343.
Belova, N. A., & Travleev, A. P. (1999). Estestvennye lesa i stepnye pochvy (ekolohiya, mykromorfolohiya, henezys) [Natural forest and steppe soils (ecology, micromorphology, genesis)]. Dnepropetrovsk University Press, Dnepropetrovsk (in Russian).
Bozhko, K., & Bilova, N. (2020). The influence of the slope exposure on the soil aggregation and structure, water stability of aggregates, and ecological micro-structure formation of the ravine forest soils in Pre-Dnipro Region (Ukraine). Ekológia (Bratislava), 39(2), 116–129.
Carter, M. R., & Gregorich, E. G. (Eds.). (2008). Soil sampling and methods of analysis. CRC Press, Boca Raton.
Chen, L., Li, Y., & Zhang, Z. (2023). Impact of land use type and slope position on the erodibility of karst hillslopes in Southwest China. Catena, 233, 107498.
Ding, H., Zhu, H., Sun, R., Wen, W., & Bi, R. (2024). Variation in the physical properties of soil in relation to natural and anthropogenic factors in the hilly loess region of China. Catena, 236, 107751.
Dong, L., Li, J., Zhang, Y., Bing, M., Liu, Y., Wu, J., Hai, X., Li, A., Wang, K., Wu, P., Shangguan, Z., & Deng, L. (2022). Effects of vegetation restoration types on soil nutrients and soil erodibility regulated by slope positions on the Loess Plateau. Journal of Environmental Management, 302, 113985.
Dou, Y., Yang, Y., An, S., & Zhu, Z. (2020). Effects of different vegetation restora-tion measures on soil aggregate stability and erodibility on the Loess Plateau, China. Catena, 185, 104294.
Duan, L., Sheng, H., Yuan, H., Zhou, Q., & Li, Z. (2021). Land use conversion and lithology impacts soil aggregate stability in subtropical China. Geoderma, 389, 114953.
Eckmeier, E., Gerlach, R., Gehrt, E., & Schmidt, M. W. I. (2007). Pedogenesis of Chernozems in Central Europe – A review. Geoderma, 139(3–4), 288–299.
Gao, Y., & Yang, P. (2023). Temporal and spatial distribution of soil water repellen-cy in grassland soils and its relation to soil moisture, hydrophobic matter, and particle size. Science of the Total Environment, 904, 166700.
Gorban, V. (2021). Robinia pseudoacacia and Quercus robur plantations change the physical properties of calcic chernozem. In: Dmytruk, Y., & Dent, D. (Eds.). Soils under stress. Springer, Cham. Pp. 95–103.
Gorban, V., & Huslystyi, A. (2023). Changes in selected properties of calcic chernozem due to cultivation of Robinia pseudoacacia and Quercus robur. Folia Oecologica, 50(2), 196–203.
Gou, Y., Chen, H., Wu, W., & Liu, H.-B. (2015). Effects of slope position, aspect and cropping system on soil nutrient variability in hilly areas. Soil Research, 53(3), 338.
Guan, X., Wang, J., Liu, G., Xiao, M., Ding, Y., & Chen, J. (2023). Grain size cha-racteristics of surface sediment in the Jilantai Salt Lake Protection System after long‐term wind‐sand activities. Land Degradation and Development, 35(1), 321–333.
Guo, M., Chen, Z., Wang, W., Wang, T., Wang, W., & Cui, Z. (2021). Revegetation induced change in soil erodibility as influenced by slope situation on the Loess Plateau. Science of the Total Environment, 772, 145540.
Habtamu, M., Elias, E., Argaw, M., & Bulley, H. N. (2023). Effects of land use and landscape position on soil properties in Dire Watershed, Central Highlands of Ethiopia. Eurasian Soil Science, 56(7), 951–962.
Han, Y., Wang, Q., Li, F., Guo, Y., & Zheng, Y. (2023). Effects of types of farmland returning to forest on the dynamics of soil aggregate and organic carbon in Upper Reaches of Minjiang River. Guangdong Agricultural Sciences, 50(4), 84–92.
Hu, J., Huang, Z., Li, S., Liu, B., & Ci, E. (2023). Assessing profile uniformity of soils from weathered clastic sedimentary rocks in southwest China. Catena, 224, 107007.
Jiang, W., Li, Z., Xie, H., Ouyang, K., Yuan, H., & Duan, L. (2023). Land use change impacts on red slate soil aggregates and associated organic carbon in di-verse soil layers in subtropical China. Science of the Total Environment, 856, 159194.
Kobza, J., & Pálka, B. (2022). Black soils outSIDE of the INBS criteria in Slovakia. Polish Journal of Soil Science, 55(2), 67–77.
Łabaz, B., Kabała, C., Dudek, M., & Waroszewski, J. (2019). Morphological diversity of chernozemic soils in South-Western Poland. Soil Science Annual, 70(3), 211–224.
Labaz, B., Kabala, C., Waroszewski, J., Dudek, M., Bogacz, A., Gruszka, D., & Mlynek, S. (2022). Medium-term transformation of chernozems under broadleaf forests in the temperate climate of south-east Poland. Geoderma Regional, 30, e00535.
Lasota, J., Błońska, E., Łyszczarz, S., & Sadowy, A. (2019). Forest habitats and forest types on chernozems in South-Eastern Poland. Soil Science Annual, 70(3), 234–243.
Le Bissonnais, Y., Prieto, I., Roumet, C., Nespoulous, J., Metayer, J., Huon, S., Villatoro, M., & Stokes, A. (2017). Soil aggregate stability in Mediterranean and tropical agro-ecosystems: Effect of plant roots and soil characteristics. Plant and Soil, 424(1–2), 303–317.
Li, C., Cao, Z., Chang, J., Zhang, Y., Zhu, G., Zong, N., He, Y., Zhang, J., & He, N. (2017). Elevational gradient affect functional fractions of soil organic carbon and aggregates stability in a Tibetan alpine meadow. Catena, 156, 139–148.
Liang, P., Wang, X., Xu, Q., Zhang, J., Fang, R., Fu, Z., & Chen, H. (2023). Litholo-gy‐mediated soil erodibility characteristics after vegetation restoration in the karst region of Southwest China. Land Degradation and Development, 35(3), 1074–1086.
Liu, X., Jia, G., & Yu, X. (2021). Effects of the undecomposed layer and semi-decomposed layer of Quercus variabilis litter on the soil erosion process and the eroded sediment particle size distribution. Hydrological Processes, 35(5), e14195.
Lou, B., Wang, Y., Zhou, N., Yan, J., & Askar, A. (2022). Soil particle size composition characteristics of Pinus sylvestris plantations in Nur-Sultan City. Arid Land Geography, 45(1), 219–225.
Luo, T., Xia, L., Xia, D., Liu, W., Xu, Y., He, Z., & Xu, W. (2023). Impact of typical land use type on the stability and content of carbon and nitrogen of soil aggre-gates in Western Hubei. Ecosphere, 14(12), e4736.
Moradikeia, N., Esmali Ouri, A., Asghari, S., & Golshan, M. (2023). Comparing runoff and sediment production in three land use in Fandoghlu Area, Ardabil Province. Journal of Water and Health, 49(1), 1007394.
Ponomarenko, O. M., Nykyforov, V. V., & Yakovenko, V. M. (2022). Changes of chemical and micromorphological properties of Poltava region soils of Ukraine for the last 130 years. Ukrainian Geographical Journal, 1, 18–26.
Sarapatka, B., Cap, L., & Bila, P. (2018). The varying effect of water erosion on chemical and biochemical soil properties in different parts of chernozem slopes. Geoderma, 314, 20–26.
Strouhalová, B., Ertlen, D., Šefrna, L., Novák, T. J., Virágh, K., & Schwartz, D. (2019). Assessing the vegetation history of european chernozems through quailtative near infrared spectroscopy. Quaternaire, 30(3), 227–241.
Thiele-Bruhn, S., Leinweber, P., Eckhardt, K.-U., Siem, H. K., & Blume, H.-P. (2014). Chernozem properties of black soils in the Baltic Region of Germany as revealed by mass-spectrometric fingerprinting of organic matter. Geoderma, 213, 144–154.
Travleev, A. P. (1996). Forest soil science and steppe forest science. Eurasian Soil Science, 29(4), 390–394.
Vysloužilová, B., Danková, L., Ertlen, D., Novák, J., Schwartz, D., Šefrna, L., Del-hon, C., & Berger, J.-F. (2014). Vegetation history of chernozems in the Czech Republic. Vegetation History and Archaeobotany, 23(S1), 97–108.
Wang, H., Wang, J., & Zhang, G. (2021). Impact of landscape positions on soil erodibility indices in typical vegetation-restored slope-gully systems on the Loess Plateau of China. Catena, 201, 105235.
Wang, S., Zhuang, Q., Zhou, M., Jin, X., Yu, N., & Yuan, T. (2023a). Temporal and spatial changes in soil organic carbon and soil inorganic carbon stocks in the semi-arid area of northeast China. Ecological Indicators, 146, 109776.
Wang, Y., Wang, J., Shi, W., & Li, Z. (2023b). Effects of microtopography shaping on characteristics of eroded sediment particles of a dump slope in an opencast coal mine in China. Land Degradation and Development, 35(4), 1411–1424.
Wiśniewski, P., & Märker, M. (2019). The role of soil-protecting forests in reducing soil erosion in young glacial landscapes of Northern-Central Poland. Geoderma, 337, 1227–1235.
Xiao, L., Huang, Y., Zhao, J., Zhou, J., & Abbas, F. (2021). Effects of planting structure on soil water-stable aggregates, microbial biomass and enzyme activity in a catchment of Loess Plateau terraces, China. Applied Soil Ecology, 159, 103819.
Yakovenko, V. (2017). Fractal properties of coarse/fine-related distribution in forest soils on colluvium. In: Dent, D., & Dmytruk, Y. (Eds.). Soil science working for a living. Springer, Cham. Pp. 29–42.
Yakovenko, V., Gorban, V., Kotovych, O., Didur, O., & Lisovets, O. (2024). Visual evaluation of soil structure in low‐intensity land use systems of steppe zone of Ukraine. Soil Use and Management, 40(1), e12972.
Yang, J., Xin, X., Zhang, X., Zhong, X., Yang, W., Ren, G., & Zhu, A. (2023). Effects of soil physical and chemical properties on phosphorus adsorption-desorption in fluvo-aquic soil under conservation tillage. Soil and Tillage Re-search, 234, 105840.
Yang, Y., Wei, H., Lin, L., Deng, Y., & Duan, X. (2024). Effect of vegetation resto-ration on soil humus and aggregate stability within the Karst Region of south-west China. Forests, 15(2), 292.
Zheng, Y., Wang, Y., Zhang, Y., Zhang, J., Wang, Y., & Zhu, J. (2023). Broadleaf trees increase soil aggregate stability in mixed forest stands of southwest China. Forests, 14(12), 2402.
Zhu, G., Shangguan, Z., & Deng, L. (2017). Soil aggregate stability and aggregate-associated carbon and nitrogen in natural restoration grassland and Chinese red pine plantation on the Loess Plateau. Catena, 149, 253–260.