Air pollution tolerance assessment of selected plant species in the Singrauli coalfield, India

Singrauli Coalfield, one of India’s largest coal mining and thermal power plants, is subjected to persistent air pollution that threatens both ecosystem health and human well-being. However, information on the tolerance to air pollution of native and commonly planted tree species in this industrial region remains limited. This study evaluated the tolerance to air pollution of selected tree species to identify suitable candidates for the development and afforestation in the Singrauli Coalfield. During 2016–2017, mature leaves of Mangifera indica, Ficus religiosa, Azadirachta indica, and Eucalyptus globulus were collected from industrial and residential locations. The air pollution tolerance index (APTI) was determined using four biochemical parameters: total chlorophyll content (TCh), leaf extract pH, ascorbic acid (AA), and relative water content (RWC). The results revealed significant interspecific variations in the APTI values. Mangifera indica exhibited the highest tolerance to air pollution, followed by Ficus religiosa, while Azadirachta indica and Eucalyptus globulus showed comparatively lower tolerance. The higher APTI values of Mangifera indica indicate its superior adaptive capacity under polluted environmental conditions. These findings demonstrate that APTI-based screening is an effective approach to selecting pollution-tolerant plant species for urban and industrial landscapes. Identified tolerant species can be prioritized for green belt development and afforestation programs to improve air quality and mitigate the adverse impacts of air pollution in the Singrauli Coalfield.