Xuzhou Urban Green Space Landscape Pattern And Ecological Function And Its Optimization

By taking the Quick Bird--2 satellite image data as a main information source to analyse the image data and making the ground survey of the urban green land in Xuzhou City and using the principles of landscape ecology and urban green land system planning, the author has investigated the pattern and function of the urban green land landscape in Xuzhou City, including the composition, structure and ecological function of urban ornamental plants, the structure and pattern of the urban green land landscape and the relationship between the urban green land landscape and the eco-environmental factors by adopting 3S technique, landscape analyses technology and ecological experimental methods. Based on those research results and the goals of improving the ecological function of the urban green land and environmental quality and promoting the urban sustainable development, Some principles and planning strategies of urban green land has also been suggested as a reference to practice. Some main conclusions are described as follows:1. There are 179 plant species which belong to 54 families in urban green land of Xuzhou City. The species richness index is 0.4172, which shows that the species diversity of plants is not high. The proportion of evergreen trees, coniferous trees and shrubs was lower and resulted in lower plant landscape diversity such as monotonous plant level and bleak landscape especially in winter season.2. There were great differences of capabilities of absorbing dust and sulphur dioxide among different ornamental plant species. The species with the strongest capability were Sophora japonica L., ligustrum lucidum, ligustrum ovalfolium cv. Vicaryi, Prunus cerasfera f. atropurpurea; The species with stronger capability were Viburnum odoratissimum Var. awabuki, Pittosporum illicioides (Thunb.) Ait, Lagerstroemia indica L., Hibiscus syriacus L., Buxus microphylla subsp.Sinica; The species with general capability were Populus tomentosa Carr.,Amygdalus persica L f. duplex Rehd, Cercis chinensis.3. The structure and pattern of the urban green land landscape was unreasonable, the distribution of the urban green land is disproportional. There were more public park green land especially in southern part of the city. The structure of the urban green land weren't reasonable and the scenic forests and the public parks are the dominant green land types. The green land was dominated by small patches and the landscape fragmentation was higher which was not favorable for providing more habitats to support the species diversity. The green corridor density and the landscape cohesion were smaller which would not benefit energy and matter flow among the species. The park areas in the urban district occupied absolute superiority, but there were less community parks and public parks along the streets.4. There was close relationship between the urban green land and the urban hot island intensity...