Spatial Analysis And Optimization Of Land Use Pattern In Changchun City

The spatial pattern of land use is the basis of regional planning and development,which is of great significance to regional sustainable development.With the acceleration of urbanization and industrialization in Changchun,as well as the prominent contradiction between man and land and the sharp reduction of cultivated land,the spatial pattern of land use has developed unevenly and the land use system has changed greatly.To solve these problems,we must use scientific and systematic optimization methods to optimize the spatial allocation of land use pattern.In this study,Changchun City was selected as the research area,and the land use types from 1990 to 2020 were extracted based on object-oriented classification method by using four remote sensing images in one period every 10 years since 1990.Based on the change of land use structure,quantity,degree and center of gravity and the theory of landscape ecology,eight landscape pattern indexes were selected to analyze the land use change and landscape pattern in Changchun from 1990 to 2020,and the characteristics and existing problems of the landscape pattern of land use in Changchun were discussed.Secondly,the principal component analysis method is used to evaluate the suitability of land in Changchun.Based on the above analysis results,the ant colony optimization algorithm was used to study the spatial optimal allocation of the land use pattern in Changchun.The results have certain reference significance for the sustainable development and rational utilization of land resources in Changchun.The main research contents include:(1)Make a quantitative analysis and evaluation of the present situation of land use in Changchun from the aspects of land use quantity structure,spatial structure,degree of change and shift of center of gravity by using historical data,find out the main problems of land use in Changchun,and lay a foundation for the spatial optimization of land use pattern.(2)Quantitatively analyze the change of land use landscape pattern in Changchun from the perspective of landscape ecology,summarize its change characteristics and find its main problems.(3)From the perspective of land resource management,relevant data were used to evaluate the suitability of various types of land in Changchun,and land use was classified and graded,providing theoretical support for the research on optimal allocation of land in Changchun.(4)The ant colony algorithm was used to study the optimal allocation of the spatial pattern of land use in Changchun in 2030,improve the suitability of land use,optimize the landscape pattern,and basically achieve the optimization goal.According to the data verification,the overall suitability of land use spatial pattern in 2020 optimized by ant colony algorithm is better than the actual land use layout,and the suitability of land use is improved.After optimization,the density values of forest land and artificial surface patches,the separation index values and the average sub-dimension index values all decreased significantly,indicating that the land use layout was more complete and regular,the continuity was improved,and the landscape fragmentation was reduced.After the optimization,the fragmentation degree of cultivated land and grassland landscape increased slightly,and the separation degree index increased,indicating that according to the land suitability evaluation index of Changchun,it is difficult to regenerate cultivated land or grassland with good continuity in the limited land resources.On the whole,the optimal allocation model of land use space based on ant colony algorithm is suitable for the optimal allocation of land use space in Changchun.