| Plant communities,as the basic unit of urban green space, was the material basis for implementation of ecological functions of urban green space system, and the basic elements of urban green space landscape.respecting for the zonal distribution of plant, constructing science communities structure of urban green space, creatting a healthy and stable, vibrant landscape of plant communities, was the inevitable choice to improve the urban ecological environment and realize sustainable development of cities.In this paper, by method of typical sampling,98 plots of various green space were selected with they typical practical significance, such as city park, residential green space, unit attached green space and street green spaces etc., were surveyed and analysised with the community structural characteristics and the biological diversity as the goal, on the kind of the floristic composition of communities, community type, spatial structure, species diversity, stability and health status. On this basis, representatives of 25 communities were selected to get analysis and evaluation about the value of communities landscape and quality by the methods of BIB-LCJ and AHP. The method was discussed about how to design eco-efficient, rich in species diversity, reasonable structure and great view plant communities. the main conclusions were:1, There were 327 kinds of vascular plants, belonging to 237 genera in 97 families, in all 98 plots communities. The number of the plant families, genera, species accounted for the existing plant families in Anhui region 51.87%,21.27% and 10.18%,and there were 228 species of native plants Which accounting for 69.72% of all origined in Anhui region, indicating that plant communities of green space in Wuhu city has strong zonal characteristics. Evergreen and deciduous broad-leaved mixed forest occupied the highest proportion (46%), and show the same characteristic of what in Wuhu region.Constructive species and the dominant species of tree layers in a total of 39 species, among those, camphor occured most frequently of 67.35 percent, and widely distributed in forest natural regeneration of the camphor tree saplings and seedlings,it showed that the camphor tree play a great role in Urban green vegetation appearance of Wuhu city. There were 153 species of shrub species in shrub layers, and Osmanthus accounted for the highest frequency of 48.98%. evergreen species and deciduous tree species occupied very similar proportion in shrub layers.The canopy density of green space in park was the biggest, which upto 71.89 percent, then which of the other types of green space was lower than average. Community forest coverage and community regeneration index dropped with the increased degree of interference go all the way. coverage indicators of plant communities showed the same trend that increased with the degree of interference increased. The ratio of the importance value between Evergreen and deciduous tree layers also increased with the interference levels tended to increase, especially when the interference level from the second grade increased to third grade, while people gave the community group management excessively and exclusivity, The ratio of the importance value between Evergreen and deciduous tree layers up to 3.43 from 0.70 rapidly, reflected the people's significant preference for evergreen species in the course of artificial green construction and maintenance management process in Wuhu City. In addition, sum of the breast basal area of trees, total coverage of shrub layer, density of the trees, density of the shrubs and other indicators had shown the overall interference level and even the highly significant negative correlation characteristics, all these phenomena showed that disturbance on plant community by the people take more significant negative impact to the total biomass of urban green space.2, classification results show that, in park green spaces, and zero-interference-sample green spaces, and the natural plant communitits,the dominance index D and Margalef index R, Simpson index H', and Shannon-Wienner index H are all obvious advantages. deciduous broadleaf forest had the highest ones of the dominance index D of duff layers and Margalef index, Simpson index H', Shannon-wienner index H and Pielou index E of those deciduous coniferous forest samples were the biggest, showing that the growth environment umder the tree layer of the deciduous forest green forest will take the beneficial effects of plant growth.3, By the Assessment of the 25 representative samples of plant communities for the value of landscape view and the community quality,with the method of BIB-LCJ and AHP, method, we could found that a significant negative correlation between the aesthetic evaluation of landscape and the quality of plant communities. In the process of BIB-LCJ evaluation, groups of students and the public groups almost to get to similar conclusions. Some samples of artificial communities with clear layers,color contrast strongly, full and balance of the composition, permeability space, full of order and beauty, can often get a better evaluation; in AHP evaluation, the evaluation system is a group more concerned about the amount of green space structure, species diversity and community stability and self-maintenance mechanism,Stable development of succession, ecological function effectively in the communities easier access to recognition, therefore, the natural communities with no interference and those semi-natural communities with lower grade of interference obvious advantaged in the evaluation, scored higher, while plant communities of artificial green space with higher levels of interference scored lower.4, from the perspective of ecological design, urban green space can be divided into four types of green space, as view-type green space, eco-type green space, toured and rested-type green space, and producted-type green space.view-type green space should be designed to obey and serve the aesthetic requirements of public, paying more attention to its social benefits. eco-type green space should be more in pursuit of a higher level of biological diversity, complex community structure and stability of community self-maintenance mechanism. In toured and rested-type green space, according to its different areas divided by the requirment of the function, most of those should be designed as eco-type green space, the others should be designed as toured and rested-type green space. producted green space should focus on the growth and development of individuals within communities, provide good habitat conditions.
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