Conclusion
The air quality score in UKM is 8.39±11.64. The mean pH value for bark of the palm trees hosting the lichens is
4.88±0.48 and the mean nitrogen content of the tree barks is 0.5567±0.3431%. Overall, 27 areas of study can be
divided to three groups, which is polluted area, moderately clean areas and clean areas. The overall air quality at the
UKM campus is moderately clean. However, monitoring and control are required to rescue the effect of pollutants to
create an environment of clean air at the University campus. The study involves multidisciplinary researchers in the
field of chemistry, botany, geography, mathematics, education, environment and the public at large.