Study On Application And Optimization Of Urban Trees In Chizhou City

The current situation of urban tree application in the green-lands in Chizhou city was investigated by using methods of specific survey of green-land type. Based to the results from this investigation, a full discussion was made on the basic principles of urban tree selection. Some measures and strategies for urban tree design and optimization of urban tree structure were put forward. It was determined the optimal selection of the street trees and the different functioning trees.According to the results of this investigation, it is clear for understanding the current status and its effects of urban tree application in Chizhou city. At present, there were a total of280tree species (including variety) which were in64families and141genera in the urban green-lands. Amongst those tree species, arbor trees are131species, shrubs88species, bamboos and woody vines21species. The ratio of arbor to shrub is1:0.78. There are90evergreen and150deciduous tree species with a ratio of evergreen to deciduous species of1:1.67. Within urban trees, the commonly used trees were116species covering48.3%of the total tree species. There is a total of127native species, of which arbor trees are73species and contribute57,5%, Within the native species, evergreen trees are50species and all grow well in the different green-land. Among the deciduous trees,68species (88.3%of a total of77species) grow well.The shortage of urban tree selection and application in Chizhou was analyzed. Those include low tree species richness and diversity; great attention to ornamental trees and few application of economic plants; more application of slowly-growing trees and less fast-growing ones; a unitary greening and poor for vertical greening; emphasis on evergreen trees while not on deciduous species.On the basis of the investigation, a tentative suggestion was made for urban tree application. The following principles should be considered:dominant in native species and active introduction of exotic species to insure a high species diversity; emphasis on ornamental trees and active application of economic species to increase economic benefits; quantitative increase in fast-growing trees and appropriate control of slowly-growing trees to accelerate urban greening; strength of ground greening and extension of vertical greening to increase green biomass; maintenance of the dominant in deciduous arbor trees and regulation of the ratio of evergreen arbor trees to promote green quality.On the basis of the investigation on urban tree diversity and application of landscape trees, the measures and strategies for urban tree design and optimization of urban tree structure were put forward.