Banyan, peepal best for industrial areas: ISTAR researchers

AHMEDABAD: The four major cities of Gujarat — Ahmedabad, Surat, Vadodara and Rajkot — all have harmful chemical industry clusters near them. A question that is pertinent is which local trees can reduce air pollution and protect the population from harmful gases emitted by such industrial units.
A team of researchers from the environmental science department of the Institute of Science and Technology for Advanced Studies and Research (ISTAR), Vallabh Vidyanagar and local bodies found that trees species such as banyan, peepal, Ashoka and champak have proved effective in controlling pollution.



The ISTAR researchers measured various factors — such as air pollution tolerance index (APTI) and the anticipated performance index (API) that were key determinants of minimising the threat from industrial areas. The study was mostly carried out in a 3km radius from the Nandesari industrial area, which has a good amount of greenery and less air pollutants nearby. To collect gaseous and particulate pollution, a high volume air sampler was used for 24 hours, with a flow rate of one litre per minute.

ISTAR researchers Dhruti Patel and Nirmal Kumar calculated scientific parameters such as total chlorophyll, ascorbic acid, leaf pH, relative water content and used them to define the sensitivity or resistance of plants to different concentrations of air pollutants.

“Plant sensitivity and tolerance to air pollutants varied with above parameters. Chlorophyll content decreased due to production of reactive oxygen species (ROS) in the chloroplast underwater stress condition,” the research states.

Patel and Kumar observed that changes in chlorophyll content caused a change in the rate of photosynthesis. In the plant, higher ascorbic acid concentration in leaves lead to an effective protection of thylakoid membranes from oxidative damage under water stress conditions.

“Alkaline particles such as limestone and dust in the air usually damaged plant surfaces while high pH improved tolerance against air pollution,” observed the study.