Search

Particulate matter (PM), an extremely serious type of air pollution, leads to numerous human diseases. Mitigating PM in the urban city, where resident density has been increasing, has been a major challenge. The increase in residents leads to increasing traffic, the primary source of PM in urban areas. Plants play an important role in reducing PM and maintaining an ecological balance. For some Asian countries, such as Korea, with differing seasons and environmental conditions, PM accumulation and plant survival are greatly impacted by environmental conditions. In this study, we analyzed the amount of PM accumulation on the leaf surfaces and wax layers of 24 plant species during four seasons (spring, summer, autumn, and winter) to determine the PM accumulation in plants under different environmental conditions. The leaf traits of plant chlorophyll a (Chl a), chlorophyll b (Chl b), total chlorophyll (TChl), relative water content (RWC), leaf extract pH (pH), and leaf specific area (SLA) were analyzed to determine the influence of PM on plants and the relationship between PM and leaf traits. In this study, we found that the amount of PM accumulation differed among plants and seasons. Among the 24 plant species, plants Pinus strobus, P. parviflora, P. densiflora, Euonymus japonicus, and Acer palmatum were most adept at PM accumulation. Leaf structure, environmental conditions, such as PM concentration, and rainfall may be the main factors that impact the ability of plant leaves to accumulate PM. The plant leaf traits differed among the four seasons. PM accumulation on the leaf was negatively correlated with SLA (in all four seasons) and pH (in spring, summer, and autumn). PM was negatively correlated with Chl a, Chl b, and TChl in summer.

Particulate matter (PM) is the most dangerous form of air pollution and is known to cause severe health problems to humans. Plants as biological filters can reduce PM in urban areas by accumulating PM on the surface and epicuticular wax of leaves. The present study determined the amount of PM (large PM (10–100 µm) and coarse PM (2.5–10 µm)) collected on 10 plant species from two sites (urban forest and roadside) of Cheongju City, South Korea. Selected leaf traits (chlorophyll a (Chl a), chlorophyll b (Chl b), total chlorophyll (TChl), carotenoid, relative leaf water content (RWC), specific leaf area (SLA), and pH of these plant species at the two sites were concurrently determined to find about the correlation between the leaf straits and PM accumulation on leaf. Study results showed that the amount of accumulated large PM (10–100 µm) and coarse PM (2.5–10 µm) were different depending on the plant species and the collection site. Plants from the roadside tended to have higher amounts of PM accumulation as compared to the same plant species from the urban forest. In addition, the amount of PM accumulated on the leaf surface was higher than that of the epicuticular wax. PM accumulation on the leaf surface was positively correlated with the amount of PM accumulated on the epicuticular wax. Among the 10 plant species selected, P. strobus, P. densiflora, M. denudata, and S. vulgaris were the most effective plant for PM accumulation, while M. glyptostroboides was the least effective plant ones. Chl a, Chl b, TChl, and carotenoid contents were higher in plants collected along the roadside than in those collected from the urban forest, whereas RWC was higher in plants from the urban forest. No distinct tendency was noted regarding the pH. Coarse PM (2.5–10 µm) was negatively correlated with leaf traits of plants along the roadside. The tolerance of plants to pollution might be due to an increase in chlorophyll content. Features of the leaf were also essential in increasing PM accumulation on the leaf surface.

High concentration of particulate matter (PM) threatens public health and the environment. Increasing traffic in the city is one of the main factors for increased PM in the air. Urban green spaces play an important role in reducing PM. In this study, the leaf surface and in-wax PM (sPM and wPM) accumulation were compared for 11 plant species widely used for landscaping in South Korea. In addition, biochemical characteristics of leaves (ascorbic acid chlorophyll content, leaf pH, and relative water content) were analyzed to determine air pollution tolerance. Plant species suitable for air quality improvement were selected based on their air pollution tolerance index (APTI) and anticipated performance index (API). Results showed a significant difference according to the accumulation of sPM and wPM and the plant species. PM accumulation and APTI showed a positive correlation. Pinus strobus showed the highest PM accumulation and APTI values, while Cercis chinensis showed the lowest. In 11 plants, API was divided into five groups. Pinus densiflora was classified as the best group, while Cornus officinalis and Ligustrum obtusifolium were classified as not recommended.