The article presents the results of a study on the impact of industrial emissions of the toxic gases SO₂ and NO₂ on the morphometric and biometric parameters of self-sown and one-year-old juvenile Sophora japonica L. plants within the southern industrial zone of Odesa (Ukraine). The aim of the research was to assess the response of young S. japonica plants to the influence of aerogenic pollutants and to identify morphometric traits suitable for the bioindication of technogenic stress in urban ecosystems. Sampling was conducted in July 2023 at three monitoring sites differing in air pollution levels: two experimental plots located within the impact zone of the Odesa Oil Refinery and one relatively clean control plot situated in Oleksandrivskyi Park in central Odesa. Monitoring site I was characterised by a moderate level of pollution (average gas concentrations: SO₂ – 0.14 mg/m³, NO₂ – 0.12 mg/m³) and was located 3 km from the emission source. Monitoring site II had the highest pollution level and was situated 2 km from the refinery, where the concentrations of SO₂ and NO₂ reached 0.28 mg/m³ and 0.23 mg/m³, respectively. According to the Odesa Municipal Sanitary Committee, the concentrations of sulfur (IV) oxide and nitrogen (IV) oxide in the control area did not exceed the maximum permissible concentrations. The results demonstrated that prolonged exposure to aerogenic pollutants leads to a marked suppression of growth processes in young S. japonica plants, particularly through the inhibition of axial organ development and a reduction in the photosynthetic surface area. Significant decreases in main root length, leaf blade area, and total assimilative surface index were recorded under conditions of elevated technogenic pollution. These findings indicate the high sensitivity of the introduced species S. japonica to sulfur and nitrogen oxides, making it a promising species for phytomonitoring and environmental bioindication in industrially affected regions. Based on the obtained data, the study recommends the use of morphometric traits such as main root length, leaf blade area, and assimilative surface index as reliable diagnostic indicators for assessing the physiological state of young Sophora japonica L. plants in technogenically polluted ecosystems and for monitoring the impact of industrial emissions on urban vegetation.

Key words: juvenile growth, biometric parameters, industrial emissions, toxic gases SO₂ and NO₂, leaf surface area.