Welcoming the tree census ordered by the Delhi Government to determine the profile, age, health and species of trees, an environmentalist at Delhi University said beyond the numbers and aesthetic beauty of trees to protect green belt area, the effective plantation is the need of the hour to stem pollutants in Delhi air.
Knowledge of Air Pollution Tolerance Index (APTI) plays pivotal role in absorption and detoxification of toxic air pollutants leaving the air relatively cleaner, they argued.
A research conducted by the Department of Environment Science, Delhi University, taking into account the APTI value of 20 plant species recommended that Azadirachta Indica (Neem ), Ricinus Communis (Castor Bean), Prosopis Juliflora (Kabuli Kikar, Vilayati Babul), Dalbergia Sisoo (Sheesham) and Delonix Regia (Gulmohar) are the tolerant species and can be used for green belt planning.
“As tolerant species can play a vital role in absorption and detoxification of toxic air pollutants, our research work with students has computed APTI at different land use sites, for instance - traffic intersection, riverine, institutional and vegetated,” said Dr Chirashee Gosh, Senior Assistant Professor, Delhi University.
Delhi has 20.8 per cent of tree cover area. Among the categories of tree C3 and C4, C4 is considered good in the perspective of the cleaning the air. Considering the tree covered area, Gosh said effective plantation with the study of different land use site will help to reduce the air pollution in the city.
“like human beings, plants also have a defence immune mechanism which helps to protect the plant and increases the pollution tolerance power and plant life. C4 plants have a higher level of that defence mechanism,” said Gosh.
“The life of plant faces threat because of two type of pollution; Dust Pollution and Gases (vehicular emission) pollution. C4 plants are most efficient in photo synthesis and henceforth have strong defence mechanism,” Gosh further elaborated.
Considering the human health factor, Priyanka, a research scholar said effective plantation will help to protect human being from harmful effect of Volatile organic Compound (VOC). “VOC is released during the transmission of oil in vehicles. The harmful gases released from the vehicular emission cause lung cancer. The plants having the high tolerance power will help in cleaning air,” added Priyanka.