Seasonal variations in accumulated particulate matter on leaves of four major tree species in Korea

Tree planting is a countermeasure used to mitigate the effects of the high concentrations of atmospheric particulate matter (PM), because trees have a strong ability to adsorb PM. However, owing to the limited information on PM accumulation on leaves throughout the year, guidelines for the implementation of urban forests cannot be provided. Therefore, in this study, we measured PM accumulation in leaves to compare the PM-reducing ability of four common species (Metasequoia glyptostroboides, Prunus yedoensis, Spirea prunifolia f. simpliciflora, and Zelkova serrata) during one growing season. We collected leaves almost every two weeks from 7 May to 23 October 2019, in Seoul Forest Park. We then measured the PM quantities on the leaves before and after rainfall (28 mm/h) to determine the amount of PM that washed off. We found that the average PM 10 (PM