Investigation And Landscape Research On Plants Of Nanjing Ming Dynasty City Wall (from East Water-Gate To Lion Rock)

Nanjing Ming Dynasty City Wall is magnificent and in a great scale, which is the largest masonry city wall in the world in history and the longest of all in existing ancient city walls of capital in China, known as "Number One City Wall in the World". It took full advantage of natural scene and adopted free style instead of square type, surrounding mountains, rivers, city and forests, and has a high aesthetic and artistic value. As was listed on the application for the World Heritage, Nanjing Ming Dynasty City Wall is more and more famous, so attention on its protection, development and management is increasing. Both epiphytic plants of Nanjing Ming Dynasty City Wall and plants in greenbelt along it have a great effect on it in view of protection and aesthetic. Therefore, this article aims to investigate and analyze both of them and find optimization methods for them, and provide scientific basis on protection, management, and optimization of Nanjing Ming Dynasty City Wall.In this study, the existing Nanjing Ming Dynasty City Wall (from East Water-gate to Lion Rock) is divided into11sections. The investigation of vegetation was set in autumn (from October to November) and spring (from April to May). The lists of epiphytic plants and plants in greenbelt were made and its community features and ornamental characteristics were analyzed in this article. The main conclusions are as follows:(1) There are154species of vascular plants belong to125genera,62families on the11sections of Nanjing Ming Dynasty City Wall from East Water-gate to Lion Rock. Life forms of them are mainly annuals and perennial herbs. Its vegetation type conforms to that of Nanjing area, which shows native obviously.(2) Comparing life forms of epiphytic plants in spring with that in autumn, we can know that seasonal variations of woody plants and lianas are smaller than herbs. Dominant and subdominant species are much more in autumn than in spring. Lianas are obviously dominant both in spring and in autumn. (3)39%of the epiphytic species of Nanjing Ming Dynasty City Wall only appeared on one of the11sections, which are mainly herbs. Each section owned at least one accidental species. Broussonetia papyrifera, Paulownia fortunei, Lycium chinense, Ficus pumila, Polygonum multiflorum, Ixeris sonchifolia, Corydalis edulis can be found on each of the11sections, which have the highest occurrence frequency. Most of dominant and subdominant species have higher occurrence frequency. Dominant and subdominant species with higher occurrence frequency are much more in autumn than in spring.(4) Through ornamental characteristics analysis of flowers, fruits and leaves of epiphytic plants, we can know that the number of foliage-watching species is largest of all, but lacks in color-leafed plants. The colors of flower-watching species’flowers are mainly yellow, so they are not very colorful. The number of ornamental fruit species is the least, and the colors of them are mainly red and black. Flower-watching species are more in spring and summer, and ornamental fruit species are more in summer and autumn. In winter, there are only a few of evergreen vines and ferns, so the scene in winter must be miserable.(5) There are346species of vascular plants belong to251genera,98families in greenbelt along Nanjing Ming Dynasty City Wall from East Water-gate to Lion Rock. Herbs are various, mainly wild. Trees and shrubs are not obviously native. Vegetation type of plants in greenbelt is mixed forests, dominated by deciduous broad leaved species, which conforms to Nanjing typical zonal vegetation characteristics.(6) Ornamental species in greenbelt along Nanjing Ming Dynasty City Wall are abundant and the landscape of that is good. Main shortcomings are as follows:The kind of flower-watching herbs is few, and lacks of flower-watching species in blue and violet. The kind of ornamental fruit species is much fewer in winter and spring, which is bad for the survival of resident birds. Color-leafed herbs are a bit short, and aromatic herbs have not been well used.(7) According to the similarity coefficient of plants in each section of greenbelt along Nanjing Ming Dynasty City Wall, the landscape of that is obviously different from each other. According to the abundance and occurrence frequency, flower-watching and ever color-leafed trees in small size and shrubs are widely used, but herbaceous ground cover, flower-watching species in winter and some species of distinguishing feature have not been used well. Wild ground cover is mainly annual herbs with great seasonal variations, different species are very different from each other in ornamental value, and they should be treated differently. (8) Greenbelt along Nanjing Ming Dynasty City Wall from East Water-gate to Lion Rock is mainly public green area; some is residential green area or road area green area. Some of the city wall was repaired in recent years, which is in low degree of weathering and low coverage of vegetation, and should be improved. The main shortcomings are as follows:Tall and fast-growing trees in greenbelt are too close to the city wall. The kind of herbaceous ground cover is not quite enough; the lawn is degenerating or even replaced by weeds because of shading or trampling. The arrangement of trees, shrubs and grass is not reasonable enough, and the landscape is miserable in autumn and winter.(9) The characteristics of epiphytic vegetation of the city wall and vegetation in greenbelt along the city wall are summarized. The pros and cons of different types of epiphytic plants are analyzed. Some optimization recommendations on epiphytic plants and plants in greenbelt are proposed, too.