Studies On Ecological Security And Land Use Dynamic Changes Of Xi'an City

Land use and land cover change (LUCC) include natural quality and changes of mankind utilized way. The study of land use change includes two levels: the global one and the regional one. The former emphasizes the influence of the changes of the land use on the global environment, and the later focuses on the functions of land use changes on the regional socio-economic sustainable development and ecological security. The research of land use changes is attracting more interest in the field of global change research. The study on land use changes and its driving force are the frontier questions of geographic research. It mainly studies the influence functions that nature motives and mankind activities have on the changes of the Earth system. It is contemporary international geosciences, especially the important content of the systematic research field of the Earth surface layer. Researches of natural and social driving forces of land use change play an important role in understanding mechanism management and setting up predictional model of land use change. Thus, analyzing the law of land use dynamic change and the main driving forces are significant in sustainable using of regional land and ecological safety.The urban-rural district lies in the edge area in the city, and is the intermediate area of economical development of both urban and rural areas, which influences human activities greatly. The question of land use is quite serious. Monitoring dynamic changes of land use, adjusting scientifically and preventing expediency act or blindness in land use are significant for hannonizing the contradiction of mankind and land, optimizing industrial structure of urban-rural district, guaranteeing ecological and food security, and realizing social economical sustainable development.Xi'an is one of the megalopolises of the Midwest of our country. As the provincial capital of Shaanxi Province, Xi'an is not only the political, economical, scientific and technological, cultural and traffic center of Shaanxi Province, but also the joint of traffic and communication of the western and eastern area of our country. However, with the rapid development of society and economy, and rapid urbanizational process as well, the problems of land use change are becoming more outstanding in urban-rural district. For example, the contradiction of land use is becoming dramatic, and thestructure of land use is unreasonable. The pollution of land is serious, and the ratio of land use is reduced. All these restrict harmonizing development of society and economy and ecological security of Xi'an city greatly.Xi'an city is chosen as the study object of the dissertation, and the urban-rural district in Xi'an is the emphases. Utilizing land ecology and ecological economics theory and the thoughts of sustainable development, through GIS technique, the dissertation regards county, district, villages and towns as the unit of the data statistics, and analyzes the land use situation by relevant materials and map, proceeds with dynamic change of space-time for land use. And according to the dynamic change model of land use, the quantitative change of land resources, the change of land use structure, the change of land using degree, and the area differentiation of land use change from 1990 to 2002 are analyzed. Based on the analysis, the laws of land use changes are drawn at last, and environmental and ecological consequences of land use are analyzed. Secondly, the paper quantitatively analyzes the driving factors of land use dynamic changes by mathematic statistical method, and sets up line shape regressive model between dynamic changes of land use and the driving factors. Finally, the land sustainable use measures in Xi'an city are achieved.The dissertation consists of seven parts. The first part summarized the significance of the research, the developing situation in our country, the international land use changes, and the selection of research area. The general situation of nature and socio-economic development in Xi'an city is introduced in t...