Air pollution tolerance index and anticipated performance index of some plant species for development of urban forest

Urban forest is a collection of trees growing in urban area. Green plants are well known for their abilities to reduce air and noise pollution. It is important that plants used for the development of urban forest must be tolerant to air pollutants. There must be some criteria to select tolerant plants for urban forest and for that two indices viz. air pollution tolerance index (APTI) and anticipated performance index (API) can be a good tool. In the present study, 29 plant species commonly found in urban area of Varanasi, India, has been evaluated for their APTI and API. Based on these two indices, the most suitable plant species were identified and recommended for development of urban forest in Varanasi for long-term air pollution abatement. It was revealed that Ficus benghalensis L. and Ficus religiosa would be excellent performers. Similarly Polyalthia longifolia, Ficus glomerata (Roxb.), Anthocephalus indicus and Mangifera indica were estimated to be very good performers. In the similar fashion Cassia fistula L., Drypetes roxburghii, Terminalia arjuna, Psidium guajava L., Millingtonia hortensis and Dalbergia sissoo were estimated to be good performers with respect to anticipated performance index.