| Based on using a part of aerial photo in autumn in 2006, topographic map in scale of 1:1000 and land utilization map of Zhengzhou city in 2005, taking northwest quadrant transect of Zhengzhou for example (along both sides of Jing-Guang Railroad, north to the Yellow River in Zhengzhou City domain border, south to Jinshui River nearly , L 25 km, W 6 km), this paper corrected aerial photograph with the support of topographic map and land utilization map and interpreted the landscape classification of it by combining GPS field investigation data.Green space landscape was classified into woodland, open forest land, waste-grassland, nursery, vegetable land, cultivated land, urban greenland, garden plot, unutilized land and pond- water-wetland 10 types. Transect researched was separated into 5 equidistance gradients artificially. This article selected six parameters such as landscape diversity, landscape density, landscape fragmentation and so on, did data statistics and analyzed the results in virtue of the software photo, cad and excel for instance.Focusing on the characteristic of gradual change of green space pattern in the urban fringes of Zhengzhou city, selecting urbanization interference index and establishing data analysis model between green spatial pattern and urbanization interference, and in accordance with the value of ecosystem services theory and landscape planning theory, the paper put forward some measures to optimize the pattern of green space and provided a scientific basis for ecological construction of the domain of Zhengzhou City. Main contents of specific study and research results are as follows:The analysis results of the green space's landscape composition show that spatial distribution of green space took on an increasing current along the gradient direction. Green space of each gradient zone accounts for 15.4%, 48%, 78.47%, 77.34% and 94.82%. Meanwhile, the comparative analysis on composing component of each gradient zone indicates that the green space composition in city center took urban greenland as main and in urban fringe took vegetable field and farmland as main. Economic structure in the course of urbanization, citizen's requirement for leisure vacation and exploitation of residential land in urban directly determined the land use patterns and ultimately affected the composing component of green space and the spatial expansion speed in urban fringe.The result by analyzing gradual changes of green space pattern shows that the composition area of green space, landscape diversity and evenness index increased along the gradient direction, patch density, edge density, shape index and fractal dimension increased with the increasing distance to city center and landscape fragmentation took on a downward trend .That is aggregation took on an enhancive trend along the gradient.The characteristics of landscape pattern changes show that along with the increasing distance to the city center, landscape diversity is increasing, landscape heterogeneity is decreasing, landscape fragmentation is becoming smaller, patch shape tends to be complicated, Edge Effect is outstanding, landscape isolation is diminishing and ecological stability was enhancing ,thus the ecological service value is increasing , and vice versa is opposite. All those facts above reveal the gradual change rule of green space pattern in urban fringe of Zhengzhou.By analyzing and comparing landscape ecological service value evaluation and the composing of green space in different gradients, it concluded that contribution rate of ecological service value to total research region of each gradient were 6.13%,14.62%,17.33%,21.03% and 40.898%,presenting an ascending current along the gradient direction. In urban fringe the ecological service value of green space in plain area took on a steadily status. And the ecological service value in mountainous region(the fifth gradient zone) is the highest. These show that city's ecological service mainly roots in green space in urban fringe. Combining the characteristic of green space pattern, it elicited that a region having small landscape fragmentation, big edge density, complex shape, great fractal dimension and rich landscape diversity also had high landscape ecological service value. On contrast, it was low. All those indicate that green space pattern restricted the play of ecological service value and there was a negative correlation between them.By the correlation analysis of green space pattern index, ecological service value and urbanization interference index, it was illuminated that there was a high correlation between green space pattern (landscape diversity, diversity, shape index, fractal dimension, aggregation and ecological service value etc) and urbanization interference. The correlation coefficients are 0.942, 0.956, 0.999, 0.987 and 0.983. Furthermore, model quantified correlation analysis was built on this basis. The law of related changes between urbanization degree and green space pattern is: the stronger was the urbanization interference index ,the smaller was the landscape diversity, the larger was the landscape heterogeneity, the simpler was the patch shape, the larger was the landscape fragmentation, the smaller was the ecological service value and the lower was the ecological stability .These further confirmed the hypothesis of human moderate interference and illuminated that controlling urban spatial expansion and reducing urbanization interference are important approach to maintain landscape diversity, biological diversity and biological stability of green space.Grounded on landscape ecological planning theory, ecological service value theory and theories of landscape architecture and so on, aimed at remaining and improving the landscape diversity, Biodiversity, ecological stability, this paper puts forward some optimization measures for research region and green space pattern of urban fringe in Zhengzhou. The measures are as follows:Remain natural form of Mang Mountain, Yellow River, Ku River, Suoxu River, Jialu River etc and their wetlands and protect natural residue patch; Protect farmland, emphasizing on the farmland of the fiest and the second and the third gradient region, import the nature into city directly and make architectural space and green space infiltrate mutually; Remain the continuity between landscape ecological process and landscape ecological pattern, mainly controlling the construction of road-corridor of Beijing-Guangzhou Railway, Jiangshan Road, Lianhuo Freeway etc and river eco-corridor from Yellow River to Jialu River;Protect cultural relics such as circumvallation of Guxing Town and Mao Tse-tung's special train and so on and create green space; Make full use of abandoned land of brickfield and mine field nearby Guxing Town, Restore vegetation and improve ecological service value of green space;Introduce green agricultural ecological technology, integrate and upgrade the taste of the scenic spot of Mang Mountain and stand out the value creation of green space;Simulate space design based mainly on nature plant community and enhance naturalization of green space and ecological environment benefit, ect.The key is reducing human interference during the process of urbanization or making urbanization construction on the premise that human interference is suitable for ecological stability and ecological service value improvement. |
