Research On Coupling Coordination Between Urban Land Use Efficiency And Land Ecological Security In Yunnan Province

Urban land is the material carrier of people’s production and life,but also the basic guarantee of urban economic and social development.With the rapid development of economy and society,people’s demand for urban land is increasing day by day,which promotes the rapid expansion of urban land.The area and carrying capacity of land resources are limited,so urban land can neither expand outward uncontrollably nor pay attention only to the improvement of land use efficiency while ignoring the protection of ecological environment.Yunnan Province is a typical mountainous province in southwest China,with complex topography,high mountains,deep valleys and ravines.The dam area only accounts for about 6%,and the urban land resources available for development and construction are very limited,so it is urgent to explore the efficient use of urban land.At the same time,as an ecological security barrier in southwest China,Yunnan Province has an important strategic position of becoming the "vanguard of ecological civilization construction".It is of special significance to improve the quality of ecological environment and adhere to ecological priority and green development.The harmonious development of ecological environment and efficient land use is an important index to measure the sustainable development of regional economy and society.Therefore,in the process of urban land use,it is urgent to explore a sustainable development path that can realize efficient and rational land use and protect land ecological security under the current realistic background.Based on the review and analysis of domestic and foreign literatures on urban land use efficiency and land ecological security,this paper,guided by man-land relationship theory,synergy theory and sustainable development theory,carries out theoretical discussion and empirical analysis on urban land use efficiency and land ecological security level as well as the coordination relationship between them in Yunnan Province from 2006 to 2021.The evaluation index system of urban land use efficiency in Yunnan Province was constructed from the perspective of land input and output.SBMUndesirable model was adopted to calculate urban land use efficiency in Yunnan Province and 16 cities and cities,and the total factor productivity was estimated and further decomposed by GML index model to analyze the extent of its influence on urban land use efficiency.The EES model is adopted for the evaluation index system of urban land ecological security,and the evaluation system is constructed by selecting indexes from the three aspects of economy,society and environment.The comprehensive level of urban land ecological security in Yunnan province is calculated by the comprehensive index method,and the obstacle factors that hinder its development level are further explored according to the obstacle degree model.Based on the evaluation of urban land use efficiency and land ecological security,the coupling coordination degree model and kernel density estimation method were used to study and analyze the temporal and spatial variation characteristics of the interaction and influence degree between them.The main research conclusions are as follows:(1)From 2006 to 2021,the overall level of urban land use efficiency in Yunnan Province is relatively high,with an average value of 0.92,showing a trend of "slow increase-fluctuation-stable".In the study period,the spatial pattern of urban land use efficiency in Yunnan Province was higher in the central and northwestern regions,followed by the northeast and southeast regions,and poor in the southwest regions.The GML index is used to measure the total factor productivity and its decomposition index.The technical efficiency change index is both 1,and the change of total factor productivity mainly depends on the change of technical change index.(2)From 2006 to 2021,the level of urban land ecological security in Yunnan Province showed an overall upward trend,and experienced four stages from unsafe to relatively safe,increasing from 0.18 in 2006 to 0.77 in 2021.From the perspective of spatial distribution,during the study period,the level of ecological security in Deqing Prefecture,Lijiang Prefecture in the northwest and Xishuangbanna Prefecture in the southwest was the highest,while the level of ecological security in the eastern region was relatively low.The obstacle degree of economic,social and environmental criteria layer showed a decreasing,increasing and basically stable trend respectively during the study period,and the obstacle degree of environmental criteria layer was basically stable at 50%,becoming the primary obstacle layer.The primary obstacle factors affecting the level of urban land ecological security in Yunnan Province changed from forest coverage rate to urbanization level,air comprehensive pollution index and per capita water resources during the study period.(3)From 2006 to 2021,the coupling degree of urban land use efficiency and land ecological security in Yunnan Province showed an increasing trend,increasing from0.54 to 0.93,and the coupling stage increased from run-in to high level coupling stage.The overall coupling coordination degree showed an increasing trend of fluctuation,which increased from 0.51 in 2006 to 0.91 in 2021.The development stage of coupling coordination increased from mild dissonance to high-quality coordination through five stages.During the study period,coupling coordination degree was generally higher in the northwest and central regions,but lower in the southwest and eastern regions.In view of the above conclusions,this paper puts forward relevant suggestions to improve the efficiency of urban land use and the level of land ecological security as well as the coupling coordination degree.First,scientifically guide the urbanization process,give full play to the effect of urban agglomeration,and reasonably control the scope of urban land expansion.Second,we should rationally formulate territorial space plans,scientifically and reasonably delineate urban spatial patterns,optimize the layout of all types of land use,and do a good job in the protection,development and utilization of territorial space.Third,we should promote the optimization and upgrading of industrial structure in an orderly manner,bring into play the effect of regional cooperation by building industrial chains and forming industrial clusters,and improve the quality and efficiency of development.Fourth,we will optimize and adjust the structure of investment in fixed assets and increase funding for land ecological protection and environmental improvement projects.Fifth,we need to accelerate the construction of ecological civilization,and carry out comprehensive pollution control and resource utilization activities to improve land ecological security.