The impact of vehicle and industrial air pollutants on vegetation and the modeling of particulate matter distributions in the province of Isparta

This doctoral study aims to comprehensively evaluate the accumulation, origin, and environmental impacts of particulate matter (PM) pollution from vehicular and industrial sources across six different locations in Isparta, Türkiye (Antalya Road, Ayazmana, Eğirdir Road, Gölcük Road, İstanbul Road, and Koçtepe). Leaf and soil samples collected during three distinct sampling campaigns (28 November 2023, 16 May 2024, and 14 October 2024) were subjected to multi-analytical techniques, including ICP-MS, SEM-EDS, FTIR, and XRD. Additionally, the atmospheric transport of airborne pollutants was investigated using the HYSPLIT back trajectory model, and tree-ring based dendrochronological analyses were used to detect the ecological impact of long-term exposure. ICP-MS results from leaf samples revealed a significant increase in heavy metal accumulation during the third sampling period (October 2024). Zinc concentrations reached 31.914 µg/g in Ayazmana, 27.735 µg/g in Antalya Road, and 20.981 µg/g in Gölcük Road. The highest lead (Pb) content was observed in İstanbul Road (2.341 µg/g), while copper (Cu) and chromium (Cr) levels were elevated in Koçtepe and İstanbul Road, respectively. Soil samples similarly showed elevated concentrations of Zn (94.591 µg/g in Antalya Road), Cr (75.513 µg/g in İstanbul Road), Cu (19.664 µg/g in Eğirdir Road), and Pb (48.278 µg/g in Koçtepe), indicating site-specific industrial and vehicular influences. SEM-EDS analyses provided visual and elemental evidence of surface-level deposition of Ca, Al, and Si, particularly on leaf samples from polluted locations. In İstanbul Road, leaf surfaces showed notable accumulation of Al (2.8%), Ca (4.1%), and Si (6.4%), accompanied by stomatal occlusion and surface deformation. FTIR spectra revealed strong bands corresponding to aliphatic CH stretching (2850–2920 cm⁻¹), ester carbonyls (1729 cm⁻¹), and silicates (1030 cm⁻¹), which were periodically enhanced depending on sample type and season. XRD analyses further identified dominant mineral phases such as quartz, calcite, dolomite, and feldspar in autumn samples, indicating geogenic and anthropogenic dust inputs. HYSPLIT back trajectory modeling showed variable air mass transport patterns across the three periods. Short-range western influences dominated in November 2023, while mineral dust transport from North Africa and the Middle East prevailed in May 2024. Dry, continental air masses from the northeast influenced the region in October 2024. These patterns were consistent with FTIR and XRD mineralogical signatures. Dendrochronological assessments of Cedrus libani and Pinus nigra indicated narrow and irregular annual growth rings in Koçtepe, İstanbul Road, and Antalya Road, reflecting stress due to pollutant exposure. In contrast, Ayazmana samples exhibited short trunk structures and indistinct rings, suggesting potential environmental constraints on growth. In conclusion, PM pollution in Isparta is shaped not only by local emissions but also by long-range atmospheric transport. Leaf tissues were confirmed as effective bioindicators of metal deposition, and the integration of multi-technique analyses offered a robust framework for spatial and temporal assessment of environmental contamination. The findings serve as a scientific basis for regional air quality management and environmental policy development.