Spatiotemporal Differentiation And Driving Factors Of Multi-functionality Of Land Use In Chongqing

The multi-functionality of land use refers to the ability of different land use modes to provide private and public goods and services,which is related to the improvement of human well-being and regional sustainable development.Under the background of the new era,with the rapid advancement of industrialization and urbanization,the scarcity of land resources has become increasingly prominent due to population agglomeration and the growth of consumption demand.The dramatic changes in land use patterns have triggered a series of contradictions between social economy and ecological protection.Regional land use functions show obvious characteristics of diversification and spatial differences.How to objectively understand the spatial-temporal evolution law of regional land use function,excavate the driving factors of regional land use multi-functional spatial differentiation,and accurately locate the function and direction of regional land use have important theoretical and practical significance for realizing efficient and sustainable utilization of land resources,alleviating the contradiction between land supply and demand and promoting regional sustainable development.At the same time,multi-functional land use research in county level is also a useful exploration of land poverty alleviation under the current precise poverty alleviation strategy.Through optimizing the regional land use zoning,according to the goal orientation of land use in different functional zones,different regional land poverty alleviation and development policies are formulated to ensure the land demand for poverty alleviation and development,highlight the innovative advantages of land poverty alleviation,so as to achieve accurate and efficient poverty alleviation in poor areas.In this context,the study of multi-functionality of land use has become animportant academic topic in land science and geography.Focusing on the theme of how to improve the level of multi-functionality of land use,this paper takes 38 districts and counties in Chongqing as the research object,and establishes an evaluation index system of multi-functionality of land use based on the recognition and classification of multi-functionality of land use.On this basis,the multi-functionality level of land use in various districts and counties of Chongqing from2006 to 2016 was evaluated.Then,the spatial-temporal correlation pattern and regional differentiation characteristics of land use versatility in chongqing are analyzed to explore the leading factors affecting the spatial differentiation and differentiation of land use multifunctional level,and then targeted Suggestions for improving the multifunctional level of land use are put forward.Finally,based on the quantitative measurement results of land use multi-functionality level,the land use in chongqing was optimized for zoning,and differentiated land use control strategies were proposed for different land use functional zoning,so as to provide references for improving the efficiency of land resource utilization and realizing the optimization of land space pattern.The main research contents and results of this paper are as follows:(1)Firstly,it identifies and classifies land use versatility.Based on existing researches,it defines the connotation of land use versatility.Then,based on the perspective of the leading function of “production-lifing-ecological space”,referring to the research at home and abroad,combined with the current situation of land use in Chongqing,the multi-functional evaluation index system of land use is constructed.Combining subjective and objective methods of AHP and EVW,the weight of each evaluation index was determined,and the multi-functional level of land use in various districts and counties of Chongqing in 2006,2011 and 2016 was evaluated.The results show that: in terms of time series,the multi-functional level of land use in Chongqing is gradually rising,and there are significant differences in the speed of multi-functional level of land use among districts and counties.Spatially,influenced by regional natural resources endowment,social and economic development level,regional development policies and macro-positioning,the multi-functional level of land use in Chongqing presents a significant spatial pattern of "high in the West and low in the east" in spatial distribution.The districts and counties with higher level of multi-functional land use mainly concentrated in regional I(main urban area)and regional II(west of Chongqing),while the districts and counties with lower level of multi-functional land use mainly concentrated in regional III(northeast of Chongqing)and regional IV(southeast of Chongqing).(2)Quantitative analysis methods,such as variation coefficient,Gini coefficient,Theil index and exploratory spatial data analysis,are used to describe the dynamic evolution and spatial difference characteristics of multi-functional land use in county scale in Chongqing,and to explore the source of spatial difference and spatial correlation pattern.The results show that: in terms of spatial differences,the spatial distribution of the multi-functional level of land use in county scale in Chongqing shows a significant spatial unbalance,but the spatial differences are shrinking.The difference among the four zones in Chongqing is the main source of the total spatial difference of multi-functional land use in Chongqing.In spatial correlation pattern,the multi-functional level of land use in county scale in Chongqing has significant positive spatial correlation,showing high and low spatial agglomeration characteristics,and agglomeration effect is increasing.Significant H-H agglomeration areas are mainly distributed in region I(main urban area),and significant L-L agglomeration areas are mainly distributed in region III(northeast of Chongqing)and region IV(southeast of Chongqing).The scope of high-value agglomeration area tends to expand while that of low-value agglomeration area tends to decrease.WanZhou District of region III(Northeast of Chongqing)is a stable high-value isolated area.(3)By sorting out and summarizing the existing relevant literature,12 influencing factors are selected from four dimensions: natural conditions and resource endowment,location advantage conditions,socio-economic factors and regional policy factors.Then,using the geographical detector model,the influencing factors of multi-functional horizontal spatial differentiation of land use in Chongqing were quantitatively analyzed from the geospatial perspective.The results show that: the multi-functional horizontal spatial differentiation of land use in Chongqing is influenced by many factors.The socio-economic factors and location advantages have a great influence on the multi-functional horizontal spatial differentiation of land use in Chongqing,which is the dominant factor of the multi-functional horizontal spatial differentiation of land use in Chongqing.Natural conditions,resource endowments and regional policy factors have relatively weak influence,but they also have some explanatory significance.From the analysis results of specific impact factors,the explanatory power of each detection factor to the multi-functional horizontal spatial differentiation of land use in Chongqing is significantly different,and its influence ranks as follows: Land-average fixed assets investment > transportation accessibility > distance from the city center > populationquality > income level of residents > per capita social consumption amount > slope >topographic fluctuation > Science and technology input level > area of conversion of farmland to forestry > proportion of area of prohibited construction area > land reclamation index.(4)Based on the evaluation results of the multi-function level of land use in county areas of Chongqing,the spatial analysis and two-dimension graphics clustering methods are used to optimize the land use function zoning in Chongqing,and different management and control strategies are put forward for different land use function zoning.The results show that: two-dimension graphics clustering methods can not only reflect the consistency of land use function within each subarea,but also show the difference of land use function among different subareas.At the same time,it takes into account the continuity of space and the integrity of administrative divisions of different districts and counties,making the multi-functional subarea of land use more practicable and scientific.According to the principle of two-dimension graphics clustering methods,38 districts and counties in Chongqing are divided into eight land use functional zones:production-lifing functional zone in Western Chongqing,production-ecological functional zone in southwestern Chongqing,suburban lifing-production functional zone,urban lifing-production functional zone,ecological-production functional zone in northeastern Chongqing,ecological functional zone in northeastern Chongqing,ecological functional zone in southeastern Chongqing and ecological-production functional zone in southeastern Chongqing.At the same time,corresponding zoning control strategies are put forward for different land use functional zones.