Relationship between leaf dust retention capacity and leaf microstructure of six common tree species for campus greening

Green plants can effectively retain atmospheric particle pollution and purify the air. As an important part of the campus ecosystem, they have a significant effect on absorbing atmospheric pollutants and improving the quality of the campus air environment. Six common greening plants were selected as the object in Xiangnan University. The dust retention capacity of plant leaves, leaf micro-structure, and leaf contact angle were measured. The results show that the highest amounts of dust removed by Osmanthus fragrans Lour was 3.451 g/m2, and the least amounts of dust removed by Magnolia denudata Desr. was 1.005 g/m2, and the maximum is 4.148 times of the minimum. The micro-structure of the plant leaf surface affects the amount of dust retention. The plant dust retention capacity with gully of the leaf surface and fluff, stomata, and sawtooth structure is relatively strong; The plant dust retention capacity with smooth, wax layer, leathery, and gully is relatively weak. The leaf contact area of a plant is related to its dust retention ability, that is, when the measured leaf contact angle is <90°, the leaf dust retention ability of the plant is strong. When the blade contact angle is >90°, the dust retention capacity is weak.Many studies have found that green plants can effectively retain atmospheric particle pollution and purify the air. As an important part of the campus ecosystem, few people specially study the campus ecosystem. Many scholars focus on the research on urban street trees and different districts of the city. The object of this study is more in-depth and targeted. Through the analysis of the difference of dust retention ability between common plants in campus, this paper compares and analyzes the influencing factors of the difference of dust retention ability among plants, which is not only related to the external environment but also closely related to the micro-structure characteristics of plant leaves. The research on the dust retention ability of different plants will help to better control dust and atmospheric environmental pollution, improve air quality, and select plants with strong dust retention ability as green plants on campus, which will play an important role in reducing dust pollution on campus.