Abstract: Aiming at providing basic informations on dust capturing capacity of different tree species and criterions for selecting trees in landscape design, this study selected 26 deciduous broad-leaved tree species widely used in urban landscaping in Beijing to measure the dust capturing both in field and indoor experiments. The dust deposition per unit leaf area of each species was quantified by determining the mass difference before and after the treatment of blades. The dust deposition per leaf and plant were further calculated for each species. Based on the dust capturing capacity measured in three different units, cluster analysis on different tree species was carried out from distinct dimensions. Results showed that the dust capturing capacity differed significantly among tree species, and the ranking changed with measurement units selected in the experiments. For different specific evaluation focuses, choosing a diverse unit combination as clustering factor, the 26 deciduous broad-leaved tree species were broadly divided into different categories representing different dust capturing capacity level. Dust capturing capacity was closely related to the surface characteristics of leaves, the dust capturing method, the plant structure, the leaf amount of whole plant, the dust content of the environment, etc. Therefore, multiple factors should be taken into account in the assessment of dust capturing capacity of different tree species.

Key words: deciduous broad-leaved trees, dust capturing capacity of leave, dust capturing capacity of plant, comprehensive dust capturing capacity, measurement unit of the dust capturing