Assessing of Air Pollution Tolerance Index of Plant Species in Aliero Local Government Area, Kebbi State North-Western Nigeria

Abstract

Green plants along roads can provide eco-friendly effective structure to improve air quality and to reduce human exposure to air pollutants. However, the plants used for the development of green vegetation must be tolerant to air pollutants. The present study compares the air pollution tolerance index (APTI) of different plant species found in the vegetation traffic barriers in the Aliero area, Kebbi State. Biochemical and physiological parameters (relative water content, leaf extract pH, total chlorophyll and ascorbic acid) were analyzed. The finding revealed that, Azadirachta indica had the highest (p<0.05) content of Ascorbic acid (9.60±.10), Relative water contents (88.8±.31), and pH (7.53±.02) but low (p<0.05) chlorophyll contained (18.48±.06) when compared with other plant species at the experimental site (polluted site). All the plant species at experimental site demonstrated tolerance to air pollution based on APTI index. Highest APTI value (p<0.05) was observed in Azadirachta indica (33.85 ± 0.2) followed by Mangifera indica (23.57±0.5). Azadirachta indica was expected as an excellent tolerant plant to air pollution on the basis of APTI value. Higher levels of ascorbic acid content, high pH value and low chlorophyll content observed at polluted site as compared to control site, were sign of stress condition. Plant species with highest APTI value could be used in cost effective green vegetation management for reducing the levels of atmospheric pollution.