Air Pollution Tolerance Index Values Research Articles

Tolerance Levels of Roadside Trees to Air Pollutants Based on Relative Growth Rate and Air Pollution Tolerance Index

Motor vehicles release carbon monoxide, nitrogen dioxide, sulphur dioxide, and particulate matters to the air as pollutants. Vegetation can absorb these pollutants through gas exchange processes. The objective of this study was to examine the combination of the relative growth rate (RGR) and physiological responses in determining tolerance levels of plant species to air pollutants. Physiological responses were calculated as air pollution tolerance index (APTI). Eight roadside tree species were placed at polluted (Jagorawi highway) and unpolluted (Sindangbarang field) area. Growth and physiological parameters of the trees were recorded, including plant height, leaf area, total ascorbate, total chlorophyll, leaf-extract pH, and relative water content. Scoring criteria for the combination of RGR and APTI method was given based on means of the two areas based on two-sample t test. Based on the total score of RGR and APTI, Lagerstroemia speciosa was categorized as a tolerant species; and Pterocarpus indicus, Delonix regia, Swietenia macrophylla were categorized as moderately tolerant species. Gmelina arborea, Cinnamomum burmanii, and Mimusops elengi were categorized as intermediate tolerant species. Lagerstroemia speciosa could be potentially used as roadside tree. The combination of RGR and APTI value was better to determinate tolerance level of plant to air pollutant than merely APTI method.

Anticipated Performance Index of some tree species considered for green belt development in and around an urban area: A case study of Varanasi city, India

It is well established that trees help to reduce air pollution, and there is a growing impetus for green belt expansion in urban areas. Identification of suitable plant species for green belts is very important. In the present study, the Air Pollution Tolerance Index (APTI) of many plant species has been evaluated by analyzing important biochemical parameters. The Anticipated Performance Index (API) of these plant species was also calculated by considering their APTI values together with other socio-economic and biological parameters. Based on these two indices, the most suitable plant species for green belt development in urban areas were identified and recommended for long-term air pollution management.

Air pollution tolerance index of plants

In order to evaluate the susceptibility level of plants to air pollutants, four parameters, namely ascorbic acid, chlorophyll, relative water content, and leaf-extract pH, were determined and computed together in a formulation signifying the air pollution tolerance index (APTI) of plants. APTI values of 69 plant species, including herbs shrubs and trees, growing in the urban-industrial Lahartara region of Varanasi were estimated. Plants with a high index value were tolerant to air pollutants and vice-versa. On the basis of their indices, different plant groups were categorized into sensitive, intermediate, moderately tolerant plant groups were categorized into sensitive, intermediate, moderately gigantea, C. roseus, etc. were tolerant and D. sissoo, L. chinensis, C. carandus, C. rottleri, etc. were sensitive to air pollutant. The susceptibility level of plants to air pollution, as indicated through their index values, compared well with the responses of plants observed under laboratory and field experiments. The APTI determination provides a reliable method for screening sensitive/tolerant plants under field conditions where the air-shed is contamined by a variety of pollutants