Study Of Plant Community Characteristics And Landscape Design Of Mountain Parks In Chongqing Main City Zone

In cities of western China, mountain parks constructed by relying on natural mountain terrain are everywhere. The mountain parks are beautiful scenery of cities due to their stereoscopic topography, the strata of landscape and the mutual fusion with the city of them, and they are important supporter of urban forest and an integral part of overall city landscape. However, systematic research on vegetative landscape design of mountain park had been done scarcely. For this reason, this paper takes the plant communities of mountain parks in Chongqing main city zone as the research object, and studies plant communities and landscape design comprehensively. The result shows:(1) The terrain is the major factor that decides the design of the plant vegetation landscape of mountain parks. Due to the mountain parks'different location in the city and their different relative position with road and architecture as the elements of urban space, the plant communities have different idealized spatial framework modes in parks. The park terrain influences spatial change of soil thickness and soil moisture. In general, the soil thickness and soil moisture in the mountain parks both decreases with increasing of the height above sea-level, but non significant regular change had been found in the soil organic matter, and N, P, K content, which shows the conformation of plant communities of mountain parks in Chongqing main city zone is mainly influenced by soil thickness and soil moisture. Because of man-made interference, the soil organic matter and N,P,K content are not the decisive factors for the conformation of plant communities of mountain parks in Chongqing. The terrain causes the inconsistency in the light distribution of mountain parks'hillsides and valley towards differently, which influences the design of plant communities of hillsides and valleys in different slopes.The park terrain has a great effect on the spread of plant landscape,and plant communities in large patches tend to be distributed over the hilltops and hillsides. The plant design should follow the park terrain spatial attributes and behavior psychology of tourists, strengthen or weaken the spatial characteristics of the terrain, and guide tourists' recreation behavior occurred in reason.(2) The zonal vegetation type is the object imitated by the plant design of mountain parks, and is the source of design. The plant communities of mountain parks and plant communities of natural forest in Chongqing main city zone had some similarities in dominant plants species, the number of dominant species in arbor tree layer and community types. There are 1 or 2 dominant species in arbor tree layer for natural forest communities in main area. It is advisable that 7 to 9 species in plant communities of composite layer class, lto 3species in arbor tree layer and forming landscape characteristic dominated by one arbor specie.(3) The analysis and investigation of light intensity, humidity, temperature and gradient changes of plant in forest edge habitats had been done. The changing of light intensity from the edge to inner showed a gradient variation from sharp decrease, slow decrease, to unchanged. The air humidity rises from outside edge to inside edge, and the daytime temperature and the light change are positively related to law. Plant diversity increases firstly then decreased from outside edge to inside edge. The width of forest fringe effect of mountain parks in Chongqing main city zone fluctuates between 6 to 14 meters, and the biggest area is the range from the 3 meters outside edge to 2 meters inside edge.4～8 meters outside the forest edge to 4-6meters inside edge is the area that should be furnished emphatically by forest floor plants. The forest edge plant design of mountain parks should follow the law that from outside edge to inside edge, positive, half negative, shade-tolerant and shade plants be arranged in right order. Thus the design modes of representative borderland plant communities of mountain parks in Chongqing could be formed.(4) The main community types are Cinnamomum camphora forest, Cinnamomum camphora—Koelreuteria paniculata forest, Cinnamomum camphora—Pinus massoniana forest, bamboo groves, Ficus virens forest, etc. in mountain parks in Chongqing main city zone. And the evergreen broad-leaved forest takes the biggest part of them, the mixed evergreen and deciduous broad-leaved forest and the mixed broadleaf-conifer forest takes secondly. While the bamboo groves are not the biggest part,they do have significant landscape effects. The park terrain and original vegetation influence the spread of landscape mostly. The green lands with comparatively large gradient have such higher landscape connectivity, compact patch structure and lower fragmentation that they become the green background of mountain parks and emerge large forest forms and distinguished scenic forests. Restricted to the terrain, no matter it is the plantation or the wildwood, the result is close to natural succession almost, and tends to reach a climax community. Restraint in the plant functional characteristics of the botanical garden and the zoo, vegetation landscape pattern has a high fragmentation and space heterogenity, which is largely related to a higher artificial interference than other parks. From the perspective of vegetation landscape pattern, it is recommended that the design between plant communities should be made from the overall point, the unity and change of size, shape and color of the plant community patch be emphasized, the plant communities be designed in conformance with terrain ,and vegetation landscape of mountain parks be established in a stereoscopic shape.(5) The characteristics of ideal plant community landscape of mountain parks in main area are as the below:Long time of plant communities forming, diversity of plant species and community stability. The plant population should be large including number and space, and forms patches naturally. The patches of different species are arranged crossly.and an appropriate horizontal width of the dominant patch is 300 to 500 meters. The vegetative landscape has a overall unity and obvious characteristics; shrub and ground cover plants are plentiful and suitable to watch closely; the vegetation landscape has been interference artificially within limits, thus forms variety scenery in four seasons, great compatibility of colors, and excellent arrangement with seasons; the types of plant communities and the space constituted by plants make a distinction between make a distinction between the important and the lesser one.(6) According to the site environmental conditions of mountain parks, the four strategies of plant landscape design of mountain parks have been put forward, which are " Entirety, Variety, Process, the Combination of Landscape art and Plant ecology". Also, the establishment of plant communities of mountain parks should follows the other 4 principles, which are "Taking the native species as the edificators, Moderate numbers of plant community species, Variety of the whole park plants, Take actions that suit local circumstances".(7) The plant design of mountain parks should include the macro-level, meso-level and micro-level. The framework of the plant community landscape design of mountain parks is be established based on our preliminarily study, which take the spatial framework of mountain parks as the core.