Analysis of Air Pollution Tolerance Index of Ornamental Plants in Kochi: A Proximity Perspective on the Western Ghats

IJEP 46(5): 480-486 : Vol. 46 Issue. 5 (May 2026)

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Gayathri Vijayan Paruthiyil and Anisha Shashidharan*

St. Albert’s College (Autonomous), Department of Botany, Kochi – 682 018, Kerala, India

Abstract

Kochi, Kerala’s economic hub and the second-largest port city on India’s western coast, faces rapid urbanization, traffic congestion, rising vehicle numbers, air pollution and loss of greenery. Planting vegetation along roadsides and traffic islands can reduce air pollution, enhance aesthetic appeal and improve air quality without implementing strict traffic restrictions. The air pollution tolerance index (APTI) analysis helps identify plant species that tolerate air pollution, supporting urban landscaping efforts. The APTI of ornamental species was calculated using leaf pH, relative water content, chlorophyll and ascorbic acid levels and species were categorized as tolerant, moderately tolerant, intermediate or sensitive. This study highlights air pollution-tolerant ornamental plants in four high-traffic areas of Kochi. Of 34 species, Epipremnum sp., Bougainvillea sp., Cordyline sp., Chrysothemis pulchella, Hymenocallis littoralis and Lagerstroemia speciosa had high APTI values and were identified as tolerant to air pollution. Twelve species were classified as moderately tolerant, 11 as intermediate and 5 as sensitive to air pollution.

Keywords

Air pollution, Climate change, Biodiversity, Air pollution tolerance index, Urban planning, Ornamental plants, Kochi, Urban landscaping, Ascorbic acid, Leaf extract pH, Relative water content, Total chlorophyll

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