Research On Urban Land-use Change Of China Based On The Urban System

Urban land is the basic carrier of urban economic and social activities. Along with the accelerated development of social economy and promotion of global urbanization, the impact of urban land-use change on environment has grown stronger and stronger, and it also becomes current even future focus of the research field of land-use and land-cover change. China has stepped into the latter half of the middle stage of industrialization and urbanization, so the rapid expansion of urban built-up area and adjustment of land-use structure have turned into an important feature of urbanization and social economy development. Therefore, the research on urban land-use change has significantly theoretical and practical meaning. At present, this research at home and abroad is more likely to adopt multi-sequential remote-sensing images and statistical data to analyze the law of urban land use change in a single region, and comparative study among regions is relatively uncommon, especially the regional comparative study nationwide is particularly rarer. Because of China’s vast territory and remarkably regional differences, the application of regional comparison approach in the research on urban land-use change at national scale appears essentially necessary.It is in line with the above background that this thesis takes four spatial levels—the entire China, regions, provinces and major cities and the combination of horizontal and vertical direction into account, summarizes the integrated data of land-use, population, society and economy in more than600cities at the county-level and above, explores the dynamic evolution law of urban land-use scale and structure, and finally analyzes the human driving factors and socioeconomic benefits of urban land-use change. The research framework of the thesis is as follows:(1) Topic elaboration (Chapter One～Chapter Three). This part sorts out domestic and overseas research trends, explains the subject background and significance, research object and content, research approach and method, key issues to be resolved and data sources and processing of the thesis, and makes an introduction to relevant concepts and theoretical basis. (2) Analysis of the national urban land-use change based on urbanization process (Chapter Four). On the basis of reviewing Chinese urbanization and industrial structure transformation since the founding of PRC, this part analyzes the scale and structure change of national land-use.(3) Analysis of urban land-use change based on urban system structure (the rank-size structure, functional grouping structure and regional spatial structure)(Chapter Five～Chapter Seven). This part analyzes the scale and structure change of urban land-use in China from three spatial levels—regions, provinces and major cities.(4) Analysis of human driving factors of urban land-use change in China (Chapter Eight). This part first carries out qualitative analysis of human driving factors of urban land-use change from four aspects, that is, economy development, population growth, adjustment of industrial structure and adjustment of administrative divisions, and then, it applies Grey Rational Analysis to divide the principle factor and secondary factor which result in the change of urban build-up area, at last it compares the land-use structure among cities with different sizes and functions, so as to analyze the influence of scale and function factors on urban land-use structure.(5) Analysis of social and economic benefit of urban land-use change in China (Chapter Nine). At First, this part uses the method of Principal Component Analysis to evaluate the social and economic benefit of urban lands of30Chinese provincial-level administrative regions in2010, then, by integrating Cluster Analysis and intensity index, it divides and compares the types of social and economic benefit of urban land-use in30Chinese provincial-level administrative regions from2000and2010.(6) Research conclusion and prospect (Chapter Ten). This part summarizes the research results of this thesis and puts forward promising research orientation in the future.Research conclusion:affected by urbanization and industrialization level, rank, size, function, location and other factors, scale and structure changes of Chinese urban land-use show different characteristics at four spatial levels—the whole nation, regions, provinces and major cities, and its social and economic benefit also has prominent provincial differences.(1) The characteristic of national urban land-use changeThere is great difference in built-up area among cities with different ranks and sizes, the city which has higher rank and larger size possesses less proportion of number but more proportion of land-use; the percentages of residential land, industrial land, roads and squares and greenbelts are all within the appropriate range specified by the state; urban land-use structure is closely related to a city’s size and function. In the recent30years, with expansion of urban population, the total urban build-up areas in China have increased by4.57times. From2000to2010, proportions of lands for roads and squares and lands for greenbelt have increased respectively, while proportions of warehouse land, intercity transportation land and specially-designated land have reduced separately, and urban land-use structure has tended to be more reasonable; the information entropy and balance degree of urban land-use structure have decreased, which indicates that the development of Chinese cities is in the growth phase and the single function has increasingly highlighted; the city-size distributing in China has become more centralized, the increase of urban land-use scale has slowed down, and the growth rate of urban land-use scale among cities with distinct ranks is different from each other.(2) The characteristic of regional urban land-use changeIn2010, there were more city numbers and larger build-up areas in Eastern China; numbers of cities and total build-up areas were almost equal in Central and Western China; there were less cities and smaller build-up areas in Western China. Industrial land and intercity transportation land had the highest proportion in the Eastern region, lands for public facilities and lands for greenbelts possessed the highest proportion in the Central region, lands for roads and squares and municipal utilities owned the highest proportion in the Western region, and residential land, warehouse land and specially-designated land held the highest proportion in the Northeast region. From2000to2010, the Eastern region has added the most built-up areas, and its dynamic degree is also the maximum; by comparison, the Central and Western regions have added less total build-up areas, and the dynamic degree is smaller; the Northeast region has increased the least total build-up areas, and its dynamic degree is the smallest. The largest added value of urban land-use in the above mentioned regions all lies in lands for roads and squares, and the largest decline happens in specially-designated land, industrial land, intercity transportation land, residential land.(3) The characteristic of land-use change of provincial cityThe provincial city-size distributing types in China have obviously regional difference, and taking the intermediate type and centralized type as dominant ones, it is inclined to develop into higher-level and centralized types. With the influence of functional grouping structure, land-use structures in provincial cities vary greatly. From2000to2010, the provincial-level administrative regions with larger growth scale of built-up areas and higher dynamic degree have been mainly located in the Eastern region, and the provincial-level administrative regions with smaller built-up areas and lower dynamic degree have been situated in the Western region. The elastic coefficient of urban land-use in most provincial-level administrative regions has been above the reasonable value of1.12, and the urban land-use expansion has been excessively fast. The diversity index of urban land-use structure in majority of provincial-level administrative regions has shown downward trend, and the difference of urban land-use areas in functional type of cities have been growing.(4) The characteristic of land-use change in major cityThe build-up area in major cities differs considerably; in the majority of major cities of the Eastern region, the build-up area is larger, but in most major cities of the Western region, it is smaller. Influenced by types of city function, the urban land-use structure in major cities is notably diversified. From2000to2010, the majority of major cities in the Eastern region have possesses larger growth scale of built-up areas and higher dynamic degree, and most major cities in the Western region have possesses smaller built-up areas and lower dynamic degree; The elastic coefficient of urban land-use in the vast majority of major cities has been above the reasonable value of1.12, and the urban land-use expansion has been strikingly rapid. The diversity index of urban land-use structure in most major cities has shown downward trend, that is, the difference of urban land-use areas in functional type of cities have been growing.(5) Human driving factors of land-use changeEconomy development, population increase, adjustment of industrial structure and adjustment of administrative divisions are all human factors which drive urban land-use to change. Among the factors causing build-up area change in cities, the total urban population, GDP and fixed-asset investment are the most important influencing factors. The size and function of city can affect urban land-use structure, which is markedly different in cities with varied sizes and functions.(6) Social and economic benefit of urban land-useIn2010, the social and economic benefit of provincial-level administrative regions in the Eastern region was higher. From2000to2010, except Hainan and Qinghai Provinces, the rest of28provincial-level administrative regions all have achieved different degrees of reduction in average population load, and all the provincial-level administrative regions have realized separate degree of increase in average output value of the secondary and tertiary industries; high-benefit and low-benefit type of provincial-level administrative regions have been reducing, and the number of medium-benefit type of provincial-level administrative regions has been increasing correspondingly.