Study On Close-to-nature Landscape Architecture And Evaluation System On Its Plant Community

With the development of social productive forces， the process of industrialization，urbanization and marketlization accelerate continually， which bringing economic and social development， but at the same time， also causing the deterioration of ecologicalenvironment. Close-to-nature landscape architecture is an effective approach to promotethe sustainability and development of a city. The conception of close-to-nature landscaping architecture emphasizes that a human being should respect the nature and plans thelandscaping according to the nature laws. Hence, it will meet the ecological, landscaping, social or economic needs for current and next generation.In this study, we explored the conception of close-to-nature landscape architectureand proposed the principle and process for its construction according to the related theory of landscape architecture subject， forest ecology subject， urban ecology subject，restoration ecology subject and ecological aesthetics subject, etc. and other related methods such as close-to-nature forestry theory, Miyawaki Aki afforestation method and close-to-nature river and canal dredging and regulating methods. An comprehensive evaluation system was established by Delphi and AHP method, which was further used to evaluate landscaping architecture in Beijing.The close-to-nature landscape architecture could use urban plants in certain area, orselect certain species to maximize the benefit of ecology system, landscaping or human society. The biodiversity of this kind of landscaping could be abundant. Hence, it promotes the sustainability of the ecology system.The principle of the close-to-nature landscape architecture respects nature and respects the harmonious relationship between human beings and nature. Its construction process includes designing the project objectives, measuring the site conditions, investigating the vegetation situation, improving soil quality, collecting, cultivating and transplantingseedlings, as well as the landscaping protection, etc..For a plant community, the evaluation index system involves six2nd level specifications such as its composition, the vigor, the structure, the degree of disturbance, landscaping and configuration elements. There are other173rd level indexes: its characteristics, Simpson index, Shannon-Weineron index, Pielou index, number changes of seedlings, canopy density, degree of human activities, degree of natural disasters, distribution levels, degree of seasonal changes, characteristics of sightseeing, relationship with surrounding environment, characteristics of local zone, ecological structures, biodiversity, vigorof plant growth. Applying the system to evaluate the landscaping architecture in Beijing,the result shows that the values of evaluation are between0.35and0.71. Most studystands’ rate scale are concerntrated Ⅱ and Ⅲ. It was in agreement with the actual situation, which proved the validity of the system.