Comparative analysis of air pollution and Air Pollution Tolerance Index (APTI) of the tree species in Durgapur

This study provides a detailed and multi-dimensional assessment of the spatio temporal variability of air pollutants and their impact on selected tree species in the industrial city of Durgapur, India. The findings highlight not only the severity of urban-industrial air pollution but also underscore the differential tolerance of tree species exposed to varying pollution loads over time and space. Among the key findings, particulate matter (PM10 and PM2.5) consistently exceeded national and international standards, particularly in industrial zones like Angadpur. Nonetheless, concentrations of PM and gaseous pollutants showed a downward trend over time, perhaps as a result of recent regulatory initiatives. Correspondingly, trees in cleaner sites exhibited higher Air Pollution Tolerance Index (APTI), better biochemical health (ascorbic acid, chlorophyll, relative water content). Tree species such as Ficus benghalensis, Swietenia mahagoni, Terminalia arjuna, and Azadirachta indica emerged as ecologically valuable for their high tolerance (APTI). Additionally, family-wise variations in APTI revealed that Moraceae, Meliaceae, and Combretaceae families harbor species best suited for deployment in polluted zones. The development of species-specific allometric equations further enhances the predictive accuracy for carbon assessments in urban greening projects.