| As an important part of urban greenland system, street-greenbelts have a great influence on visual, ecological, practical function and cultural connotation. Recently, ecological environment in Wuhan city has been changing a lot during the progress of recreating the urban streetscape as a "green corridor". However, a lot of city landscapes had been impacted because of the urban development and city street alteration. In order to give some suggestion for the city street-greenbelts development direction, we investigated the green status of streets in the city.With data of 173 streets in Wuhan obtained by means of on-the-spot investigation, the characteristics of street cross section form, floristic component, application frequency, allocation method as well as plant ornamental have been studied. The results showed there were many problems in Greenland, such as few plant species application, the low diversity of street-greenbelts in forms, and single ornamental landscape. And some suggestions have been given for solving problems mentioned above.Comparing with the results of general investigation in city greenbelts in 2003, the whole green area ratio has been raised up a lot with per capita of 9.15m2, ratio of green area in main urban area of 32.13% and green coverage to 37.46% in the year 2008.In Wuchang area, there were 2 streets over 50-meter-wide red line in Wuchang District,1 in Hongshan District and 6 in Eastlake High-tech District.6 streets of among above 9 came up to street-greenbelt standards, and there were 5 streets over 50-meter-wide red line in Eastlake High-tech District. There were 25 streets being red line 40～50 meters width, among 14 of 25 in Wuchang District, which none of them were up to the standards; 7 in Hongshan District and 4 in Eastlake High-tech District, which all of them came up to the standards.Street cross section form in Wuchang area mainly was "one road plate with two greenbelts", a few streets were "Four road plates with five greenbelts", and many other forms were widely used in Wuchang District. There were 195 plant species for street greening, including 54 deciduous tree species,32 evergreen tree species, deciduous and evergreen shrubs in a fairly proportion as the first two, as well as 4 vine species and 29 species of cover plants or grasses, belongs to 66 families and 123 genera. Among all above, there were 43 tree species. Cinnamomum camphora and Platanus hispanica were the most widely ones planted in greenbelts.There were 96 flower ornamental species,26 fruit ornamental species and 34 foliage plant species used for street greenbelts in Wuchang area. Flower or fruit ornamentals were mostly arbor and shrub trees, and foliage plants mainly were trees. Flower season was mainly in spring and summer, fruit season in autumn; foliage plants were with autumn-color, colored or green leaves.The dust holding experiment showed that there was a highly significant difference among different plant species for dust-holding capacity, and there was a highly significant dust-holding capacity difference among different days for the same plant species as well. Rhododendron simsii had the largest dust-holding capacity with 11.7885 g/m2, and Pittosporum tobira the least with 5.6626 g/m2. Selection of plant species should take many aspects into account, for instance ecological benefit, landscape effect and so on, while a street greenbelt being built.
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