Assessing the Cooling and Air Pollution Tolerance among Urban Tree Species in a Tropical Climate.

We present the results of classifying plants at species level that can tolerate air pollution, provide cooling, and simultaneously survive and thrive in urban environments. For this purpose, we estimated the air pollution tolerance index (APTI) and anticipated performance index (API) of several species growing in a park located in central Bangkok, Thailand. The cooling effect was quantified by calculating the reduction in soil and air temperatures. (Cav.) S.T. Blake, (Jacq.) Merr., A. Juss. had the highest API score and were able to substantially reduce the temperature and were in a group of highly recommended species which also included other species like . , . , (Bertol.) Bertero ex A. DC., Pierre etc. Species from both evergreen and deciduous habitat were able to provide ambient cooling but were vulnerable to air pollution and included Sm. and L. However, there were other species which had a high air pollution tolerance but failed to provide adequate cooling, such as Roxb. and L.f. The results would be of interest to urban greenspace landscapers in such climates while selecting suitable species that can provide multiple ecosystem services ranging from air pollution tolerance to temperature reduction without reducing plant vitality.