Leaf dust capturing capacity of urban greening plant species in relation to leaf micromorphology

To provide valuable references for the greening plant species selection, planting design and location in city the present study was undertaken. Leaf dust capturing capacities of 14 common urban greening plants and their relationships with surface micromorphology has been investigated. Among the selected plant species, leaf dust capturing capacities ranged from 0.23 g/m² (Trifolium repens) to 4.51 g/m² (Pittosporum tobira), and dust accumulation of plant leaves might be reach maximum values in five days after rainfall. The particles mainly deposited on adaxial surfaces, only very few deposited in the stomatal regions on abaxial surfaces. Six plant species (Pittosporum tobira, Pinus tabulaeformis, Ligustrum lucidum, Viburnum odoratissimum, Cedrus deodara and Platanus acerifolia) showed higher dust capturing capacities (3.87~4.51 g/m²), which surface structures of their foliage were benefit for capturing particles. The lower dust capturing capacity of Trifolium repens may relate to wax tubules covered on leaf surface which creates self-cleaning properties. From the findings it can be concluded that plants with higher dust capturing capacities and these leaf micromorphological properties such as epidermal cell, wax and sunken stomas can be recommended for introducing as urban greening plant species.