CHANGES IN PHYSICAL PROPERTIES OF IRRIGATED TAKYR-MEADOW AND MEADOW-ALLUVIAL SOILS UNDER THE INFLUENCE OF CHEMICAL POLLUTION IN NAVOI INDUSTRIAL ZONE

Soil contamination by industrial pollutants poses a significant threat to soil health by altering its physical, chemical, and biological properties. While much attention has been, given to chemical and biological aspects, physical degradation remains less explored. This study assesses the impact of chemical pollution on the physical properties of irrigated meadow and meadow-alluvial soils in the industrial zones of the Navoi region, Uzbekistan. Soil samples were, systematically collected at distances ranging from 500 to 20,000 meters from major industrial sources, including the Navoi Mining and Metallurgical Combine (NMMC) and the Navoi Gas and Heat Power Plant Station (HS), and at three depth intervals: 0–5 cm, 5–30 cm, and 30–50 cm. Key physical parameters—bulk density, total porosity, particle size distribution, and micro-aggregate stability—were, measured following standardized procedures based on GOST 26213-91, ISO 11272:2017, and the Soil Management Assessment Framework (SMAF). The findings revealed a consistent degradation trend in areas close to pollution sources. Bulk density increased to as high as 1.48 g/cm³, while total porosity declined to 41.91%, compared to values of less than 1.20 g/cm³ and over 50% porosity at control sites. Furthermore, a shift in mechanical composition was, observed with higher silt and clay fractions and reduced sand content, indicating enhanced compaction and reduced aeration. Micro-aggregate stability also decreased, reflecting structural breakdown at the surface layers. Spatial analysis showed that pollution effects were most pronounced topsoil and, diminished with greater depth and, distance from the source. These results demonstrate the critical role of physical indicators in the early detection of chemically induced soil degradation. The study emphasizes the urgent need for integrated soil monitoring and targeted remediation strategies to preserve soil health and ensure sustainable land use in industrially affected regions.