Estimating and simulating dust absorption ability by Eldar pine, Oriental Arbor-vitae, River red gum and European Olive

This research was undertaken to investigate the efficacy of dust stabilization by two-year-old seedlings of four green space trees within a controlled experimental setting. Following the calibration of the dust simulation apparatus to ensure uniform dust dispersion, gas exchange measurements were taken on the seedlings, and subsequently, they were introduced into the dusting device. Dusting operations were performed at 30 and 60 g per square meter concentrations, with treatments involving one, two, and three dusting episodes at 48-h intervals facilitated by a wind pump. After confirming dust settlement, the crown and trunk sections were segregated, washed and the weight of falling dust was measured. The results revealed that Eldar pine exhibited superior dust absorption per unit leaf area (0.0063 g/cm −2 ), potentially attributed to its densely covered leaf surface with regular excrescences and copious foliage. In contrast, no discernible distinctions were observed among the remaining three species. Examining fixed dust quantities per unit crown volume unveiled significant effects for all factors except for the interaction between species and dust concentration. Once again, Eldar pine exhibited the highest dust absorption. Comparative analyses of pre- and post-dusting gas exchange data indicated that dusting significantly reduced gas exchange for olive and River Red Gum. Conversely, no noteworthy variation was observed in the case of Eldar pine (6.83 mmol/g/s decrease) and Oriental Arbor-vitae (7.39 mmol/g/s decrease). The findings further indicated that increased crown void spaces and reduced foliage density substantially decreased stabilized dust quantities per unit crown volume. Augmented dust concentration and more frequent dusting operations were correlated with heightened total dust stabilization and increased dust accumulation per unit leaf area and volume in the seedlings. Eldar pine emerged as a robust species for dust absorption, demonstrating marked superiority over the other species investigated in this study.