| In this thesis, the author systematically summarizes the research progress of ecological garden city's construction and development, evaluation method for ecological garden city and 3S methodology's application in evaluating the ecological garden city, etc. Based on the existing evaluation system of the national ecological garden city, the statistic approach has been used to build and optimize the evaluation index system of the ecological garden city. This index system is applied as the guidance along with the 3S methodology to explore and deepen the space evaluation system of the urban green space, which forms a set of theories and methods to comprehensively evaluate the ecological garden city. Furthermore, the index evaluation system mentioned above is used to comprehensively assess the construction of Changzhou city, and some strategic recommendations are also suggested for the green space construction. The main results were described as follows:(1) Based on the characteristic of Changzhou's ecological garden city construction and the evaluation standard for existing national ecological garden city, it uses the index selection method by means of combining subjective and objective, qualitative and quantitative models, to edit, reinforce and optimize 72 ecological garden city evaluation indices, and uses the principal component analysis, factorial analysis and cluster methods respectively to optimize the original indices and choose 25 indices derived by the principal component analysis, and then uses the AHP method to establish the ecological garden city evaluation index system and assign corresponding weight to each index. This index system consists of 3 first level indices and 25 second level indices (Including landscape connectivity, distribution status of road network and distribution status of population density, etc).(2) Using some indices from the index system constructed by the space data collection, such as remote sensing images, the author conducts visual interpretation for the 1:10000 aerial images of the built-up area in Changzhou city in 2005 and selects the green space information of the built-up areas. According to the patch areas, green space patch of Built-up areas is relatively fragmentized, the total number of medium and small size green space patches accounts for 98.25% of the total number of green space patches, but their total area only takes up 72.17% of the total green space area. According to the green space type, occupancy green space, other afflicted green space and manufactured green space which accounts for 87.81% of the total number of green space patches, but their total areas only takes up 81.84% of the total green space area; According to the composition of vegetation, the number of trees and shrubs account for 92.54% of the total number of the green space and their areas occupy 83.24% of the total area of green space; meanwhile using the TM images from 2005, the thesis adopts the Isodata unsupervised classification to select 5 ground feature information from the area of the city, namely urban green space, farmland, construction area, water body and other sites. The total precision degree after classification is 91.12%; the kappa coefficient is 0.88. The green space patches that have relatively large areas in the studied area mainly are located in the western and southern areas of Wujin district, western areas of Xinbei district.(3)City green space connectivity indice are used to analyze and evaluate sensitivity of green space patches, and identify city sensitivity areas and levels. Selecting 4 minimum levels of patch areas including 10,15,20 and 25 hm2, and also 5 connectivity thresholds including 200,400,800,1200 and 1600 meters, the node importance of 9 connectivity indices as calculated, and Spearman Rank Correlation Coefficient and PIOP value are used to optimize AWF index (Area-weighted flux) as the index of analyzing the connectivity sensitivity of landscape. Meanwhile, the best combination of the 400m connectivity threshold and the 10hm2 smallest patch area is determined. The results show that Hujia Mountain-Zhong Da Wan and Xi Wan Li-Dingjiawu District are the most sensitive areas, the green space sensitive areas with relatively high sensitivity are mainly located at the Northwestern area of the city, and that the green space patches in the northern and eastern areas of the city are relatively scattered and have the lowest connectivity sensitivity.(4) In this paper ten levels of single factor analysis are conducted for the seven factors such as traffic condition, water body distribution, old and rare trees in the research area. According to the grading forms from 3 groups of specialists, the author constructs green space suitability distribution pattern based on AHP model and FR model by 3 Scoring tables, uses ROC curve to test the result of 4 types of suitability. The results show that 3 groups ROC linear areas calculated by the AHP model and FR model are:0.604,0.612,0.597 and 0.724. Among them, the FR model's prediction accuracy has a relatively high reliability. The research uses this model to analyze and evaluate the suitability of Changzhou's green space. Highly suitable districts are mainly located at the western and northern areas of the city and unsuitable districts mainly located at the central and surrounding areas of the city. According to the area statistics, the highly suitable districts account for 13.14% of the total studied area and the unsuitable districts take up 17.75% of the total area.(5) According to the characteristics of Changzhou ecological garden city construction and the weighted evaluation value of each indicator the comprehensive score of Changzhou ecological garden city construction is obtained. The composite score of Changzhou's construction level of ecological garden city in 2005 was 0.6684. According to the classification table of ecological garden city construction, Changzhou's construction level of ecological garden city is at levelâ…£, which is the middle level of the ecological garden construction, compared to the data of 2008 (0.7160) and 2009 (0.7168) in order to determine the feasibility of the index system. Among them, the evaluation values of the urban ecological environment, urban living environment and urban infrastructure are 0.6297,0.7212 and 0.7115 respectively. The index of the urban ecological environment takes the largest weight and has a relatively large impact on the index system. In this index level, several factors, such as the green coverage in the built-up area, landscape's connectivity, public green space area per capita in the built-up area and native plants index, have relatively large impacts on it. According to the comprehensive analysis of the green space distribution, the green_space patch density of highly suitable districts in the studied area is relatively high, and the patch area is relatively large with the relatively low level of fragmentation. Its largest patch index (LPI), aggregation degree index (AI) and mean patch area (MPS) are clearly higher than those of the low suitable districts. The green space patches with high sensitivity and relatively high sensitivity greater than 10hm2 are mainly located at highly suitable areas, but low suitable districts are seriously interfered and the connectivity sensitivity of the green_space patches are relatively low, which would become one of the mainly focused regions in the urban green space system planning. |
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