| At present, under the rapid urbanization in China, the rate of urban expansion in the developed coastal regions of China has been far more than the average rate in other developing countries. Urbanization process can be helpful to accelerate social and economic development, provide more employment opportunities, but it can also lead to a series of questions, such as a sharp decrease of agricultural lands, the pollution for water resources, the deterioration of the living environment. Therefore, the study on urban expansion has become a focus for many researchers at home and abroad. The dynamics of urban expansion have been studied for understanding the spatial and temporal characteristics and evolution of urban expansion, analyzing the driving forces of urban expansion, simulating and predicting urban expansion using the effective simulation model. And it can provide scientific basis for urban planning management and developing strategies of the developed coastal regions.This dissertation took the spatial information extraction of remote sensing images, land landscape pattern analysis of urban expansion, spatial and temporal characteristics, driving forces analysis and simulation model as a main guideline to study remote sensing monitoring and simulation of urban expansion in Hangzhou based on the remote sensing images and GIS. Based on the establishment of urban land spatial information extraction technology system, the basic characteristics of urban expansion, spatial and temporal evolution law and driving forces of urban expansion were analyzed and understood to simulate the urban change direction and spatial distribution.The main research achievements in this dissertation were as follows:(1) Urban land use spatial information extraction methodology based on multi-sources remote sensing for a long period (1985-2010) images was developed in this study. This study took Hangzhou as a case and adopted multi-dates images (1985, 1991,1995,2000,2005 and 2010), multi-sensors (Landsat TM/ETM+ and CBERS-02 CCD and HJ-1/A CCD) as the data sources. According to the characteristics of the research object and data, the integration of spectral mixture analysis model and land surface temperature generated by thermal infrared images was used to extract spatial information of urban lands. SPOT-4 pan-image in 1999 and high resolution images of Google earth in 2000 was selected for validating the extraction results,the validation result showed the majority of differences between estimating values and interpreting values of samples ranged from -0.15 to +0.15. There was a promising accuracy. And then, the spatial distribution of urban lands in different periods was obtained by setting the threshold. Combined with the other land uses classified using the supervised classification, land use maps of Hangzhou in six periods were obtained.(2) This dissertation adopted some landscape metrics to make a quantitative analysis. The analysis result showed that landscape pattern experienced a great conversion process from 1985 to 2010 in which the agricultural landscape was replaced with the man-made landscape. In whole study period, the dominant position of agricultural landscape disappeared gradually, and its fragmentation was increasing; while urban land achieved an advantage position, and its fragmentation was decreasing. The evolution of urban expansion was analyzed using urban expansion metrics. The result showed there were some basic characteristics of urban expansion of Hangzhou from 1985 to 2010. First, the rapid increase of urban lands came along with the magnificent change of spatial distribution. The area of urban lands had increased from 8142.55 hectares in 1985 to 59066.24 in 2010. The ratio of urban land to the whole study area in 1985 was less than 10%, and the ratio of urban land to the whole study area in 2010 was more than 50%. Second, the sharp decrease of farmland came along with the increase fragmentation. The area of farmland had decreased from 73973.26 hectares in 1985 to 24103.62 in 2010. LPI of farmland had also decreased from 33.800 to 3.220. Third, urban expansion of Hangzhou had experienced the process of "diffusion-aggregation".(3) Driving force mechanism was systematically analyzed and explained based on the remote sensing image and GIS. Combined with the characteristics of Hangzhou, the DSR model of urban expansion of Hangzhou was establishment. According to the development characteristics of Hangzhou and the function of driving forces, driving forces were divided into three categories from the views of the geography, social economy and government policy. On this basis, they were reclassified to seven factors. The topography was the limited factor for urban expansion. The direction of urban expansion and urban morphology had a close relationship with topography. Geographic location gave Hangzhou a powerful resources gathering capacity and economic radiation capacity. The traffic conditions had a very significant role in promoting urban expansion. The analysis result showed that the urban main roads and highways had a great contribution to urban expansion. The regression analysis indicated that GDP, financial revenue and passenger capacity had a close relationship with urban expansion. The role of government had always been dominant in urban expansion. The adjustment of the administrative division had led to reorganization of land resources and administrative resources. It was helpful for promoting urban expansion. Urban planning of Hangzhou was a guide for the scale and direction of urban development. On the basis of the analysis of these driving forces, combining with the spatial and temporal evolution characteristics of urban expansion and measurements for controlling the failure of urban planning, the DSR model of urban expansion of Hangzhou was establishment.(4) A simulation model of urban expansion based on CBR (Cased-Based Reasoning) and CA (Cellular Automata) was established on the basis of the comparison and analysis of the current simulation models. There were problems in representing complicated relationships by using static and conventional rules. The CBR approach could deal with the problems of the rule-based approach in defining CA. It didn't need to obtain explicit transition rules, and its transition rule was implicitly embedded in dynamical cases. And the modified land ecological suitability model was used to optimize attribute indices in the case database in order to improve the computational efficiency of the CBR-CA model. This model was used to simulate urban expansion of Hangzhou from 2005 to 2010. Two validation methods of point by point comparison and spatial morphology comparison were used to evaluate the accuracy of results. The validation result showed the simulation accuracies of 2005 and 2010 were 0.81 and 0.80, Kappa statistics of 2005 and 2010 were 0.59 and 0.58. It demonstrated that this model had a high accuracy, and could produce plausible simulation results. Based on the analysis above, this model was used to predict the spatial distribution of urban expansion in 2015. The results showed the decrease of fraamentation the increase of dominance of urban land.
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