Study On Optimal Allocation Of Land Use Structure In Hefei City Based On The Coupling Relationship Between Urbanization And Cultivated Land

The cultivated land resources is not only a significant substantial basis for human survival and development but also a kind of irreplaceable natural resources and strategic reserves to maintain the function of natural ecosystem and support the development of social economic system. Since China’s reform and opening-up, the speed of urbanization continues accelerate and the proportion of urban population increased yearly with the sustainable and rapid development of social economy, a lot of cultivated land resources has been transferred from the agricultural sector to the non-agricultural sector, leading to a prominent confliction between the supply and demand of land resources.Therefore, how to scientifically deal with coordinative relations between the urbanization development and cultivated land resources protection, and to continuously improve the degree of intensive utilization of cultivated land resources have become an important research subject involving that the regional economy development can be sustained and healthy or not.At present, our country is in a critical period of rapid development of urbanization, the cultivated land resources is in the irreplaceable position in land use structure, it not only shoulders the important mission to supply food to the urban and rural residents but also takes the formidable task to provide urban construction development space. Therefore, scientific and reasonable utilization of cultivated land resource is not only the realistic requirement of social and economic development but also the meaning of land science research. However, the relationship between cultivated land and other land types must be dealt with for the scientific and reasonable arrangement and deployment of cultivated land resource, it is very necessary to conduct land use structure optimization at the proper time. In recent years, the social economic growth and urbanization process of Hefei city is faster, mutual transformation between different land use types exhibits a significantly rising trend, thus, as the research object, the land use optimization research based on the coupling relation between urbanization and cultivated land possesses strong practical significance and theoretical value.The combination of quantitative statistics and qualitative analysis method is adopted by referring to the existing research experience, taking the process of urbanization and the quantitative change of cultivated land resources as basic research mainline based on the change data of cultivated land resource from 1990 to 2010 in Hefei and relevant statistical data, the relationship between the two research projects is reasonably brought into the change pattern of regional social economic system and natural ecological system, and the coupling relationship between resources quantity and environmental quality is comprehensively and systematically researched, aiming to find the inherent relationship between the elements, such as the social economic development and natural environment change, and continue to explore its regularity and operating mechanism.(1) Dynamic analysis of quantitative change of cultivated land resources and urbanization level are given emphasis, the principal component analysis and multiple regression model are used to dig into the related factors affecting cultivated land quantity change in the study area, driving forces of the city territory cultivated land quantity change are analyzed with local conditions, analysis of the influence mechanism between cultivated land quantity change, urbanization level and social economic development is conducted, and to scientifically study on the driving mechanism of cultivated land resource change under the condition of urbanization.(2) The coordination relationship model of city territory urbanization process and cultivated land resources quantity change is scientifically constructed, and a comparative study on coordination relationships between the change of cultivated land resources and urbanization level under provincial regional and city territory is conducted, then, the coupling relationship between the quantitative change of cultivated land resources and urbanization level is discussed in detail.(3) It combines ecological niche theory with optimization goals, optimization principles of GECM and the characteristics of the land use structure, and introduces coordination coefficient of urbanization process and cultivated land, the "ecological niche- multi-objective dynamic programming" model is established orderly combining with urbanization driving factors which led to cultivated land quantity change, the optimization schemes of land-use structure which is in line with the actual regional development is scientifically proposed taking such factors as ecological environment, social economic and scientific and technological development into consideration comprehensively, aiming to achieve scientific deployment of cultivated land and other land use types.(4) The order increased hierarchy structure and judgment matrix are established and the corresponding index layer data are processed reasonably by means of Analytic Hierarchy Process(AHP) to achieve the sorting of optimization configuration schemes of cultivated land resource; The method of contrast analysis is respectively adopted to conduct correspondingly comparative study on the forecasting results, and probe into the change quantity and intensity of cultivated land resource and other land use types under different optimization configuration schemes, characteristics of different cultivated land resource optimization configuration schemes and differences of forecasting results are put forward under different situations, so as to realize the optimization of optimization configuration schemes of cultivated land resource under different situations.Relevant conclusions are mainly obtained as follows:(1)There exists strong correlation between urbanization level and cultivated land utilization, cultivated land resource quantity shows a law that it increases after first declines which likes a "spade" with the advance of urbanization, it decreases slowly in the early stage of urbanization, and it is characterized by rapid decline after a certain stage, then it is basically in a flat state. The comprehensive scores of driving forces of cultivated land resource quantity from 1990-2010 in Hefei city shows a trend of increasing, showing that driving forces which affect cultivated land resource quantity change of Hefei are gradual strengthening. The regression equation between the cultivated land and 8 secondary indexes is built through the integrated use of principal component analysis(PCA) and the original regression model, the regression coefficient indicates that the proportion of urban population and the proportion of the tertiary industry production are the main driving factors affecting the cultivated land resources quantity change with a negative correlation relationship in Hefei city, the proportion change of the proportion of urban population and the proportion of the tertiary industry production in the GDP would have strongly and directly influence on the cultivated land resources quantity change.(2)The coordination level between urbanization level and cultivated land resources quantity change of Hefei from 1990 to 2010 is measured and analyzed by using the coordination degree evaluation model of urbanization development process and cultivated land resources change, the results show that the coordination level enhances unceasingly, in addition, urbanization and cultivated land resources utilization gradually incline to harmony. The coordination degree between urbanization level and cultivated land resources quantity change of Hefei from 1990 to 2010 are mainly between 0 and 1,which is basically at the intertwined state of " reconcile " and "reluctantly reconcile" type.(3)The optimization configuration model of cultivated land use structure is constructed orderly with the gradual easy constraint method(GECM) at the core, guided by coordinated relations between urbanization and cultivated land resources according to the need of the practical study, constraints of such multiple aspects as the region’s economic and social development and urbanization process are set up scientifically on the basis of taking full account of driving forces that caused cultivated land resource quantity change, three different development scenarios were scientifically set up referring to the specific needs of the future development, land use structure optimization scheme which is in line with the development process of urbanization is then put forward.(4)According to the practical needs of production practice, the study would discuss on land use structure optimization configuration schemes respectively in such aspects as scheme comparison, scheme evaluation and scheme optimization under different situations, the results showed that: the economic benefits corresponding to land use structure at different "urbanization- cultivated land " coordination degree exhibits relative significant differences when the speed of change in the annual average level of urbanization is a constant value from 2010 to 2020 in Hefei. With the improving of the social economy level, the faster the urbanization development speed, the greater the corresponding economic benefit of land use plan, at the same "urbanization- cultivated land " coordination degree, otherwise, there is the biggest ecological benefit. At the same time, the change quantity and intensity of cultivated land resource and other land use types of different optimized configuration schemes in different situations possesses significant differences.The innovative results reached are as follows: the cyclical development characteristics of coordination degree of urbanization level and cultivated land resources quantity change in different phases of the development of urbanization are revealed. The coordination level between urbanization level and cultivated land resources quantity change from 1990 to 2010 in Hefei is measured and analyzed by using the coordination degree evaluation model of urbanization development process and cultivated land resources change, and the coordinate change curve of development process of urbanization and cultivated land resources quantity in Hefei is obtained. The coordination degree has volatility and periodicity, while it shows two complete cycles.The multi-objective constraint model which is a set of low carbon economy niche and gradual easy constraint method(GECM) is firstly established. The model guided by coordinated relations between cultivated land resources quantity change and urbanization process, is based on taking carbon emissions niche and economic niche of land use into consideration, and integrates driving factors of cultivated land resources quantity change in the study area, while taking them as constraint conditions and then applying them into case studies of regional land use planning successfully, it deals with the goal conflict between various regions, departments and organizations orderly, and realizes the optimization configuration of land use structure under the background of rapid urbanization.The screening method of the optimization configuration schemes of land use structure is put forward, which takes the Analytic Hierarchy Process(AHP) as the core, with the leading factors of meritocratic optimization configuration schemes and comparison of different optimization schemes, it is a comprehensive research method with the integration of "scheme merit", "scheme evaluation" and " scheme comparison", it can not only make scientific judging on the reliability and stability of calculation results of optimization configuration schemes in different situations but also make system analysis on the corresponding economic benefit, ecological benefit and comprehensive benefit of different optimization configuration schemes, meanwhile, it realizes scientific analysis and system discussion of different land resource optimization configuration schemes, and possesses relative operability and applicability.To sum up, China is in a critical period of building a all-round well-off society, and all regions are faced with a realistic plight of accelerating the transformation of the pattern of economic development and increasingly intensified environmental constraints. Hefei, as the "vanguard" in social and economic development in Anhui Province or even the entire central China, its confliction between land supply and demand has become more and more critical and tasks of farmland conservation has been more urgent and arduous. Therefore, in order to maintain the sustainable and healthy development of social economy, Hefei should take the overall requirement of the construction of a resource-saving and environment-friendly society as the project and give full play to the core strengths of scientific innovation in the process of economic development, continue to promote the developmental transformation from traditional extensive mode to intensive mode, and improve the utilization efficiency of the region cultivated land resources effectively; A scientific regional planning and overall land use programming should be made, adjust land use structure timely, give priority to the development of strategic industry.