Selecting Sites For Sponge Space In Changchun Basing On The Evaluation Of Sensitivity And Suitability

Constructing sponge city has already become the national strategy for the urban development at the present stage.As the pioneer of constructing sponge city,the 30 national pilot cities are in urgent need of scientific quantitative analysis technology support in the process of planning and decision making.Using large amounts of available data and technical analysis tools in the smart city is of great significance to provide scientific and effective urban planning decision-making basis of sponge city from the urban planning lead perspective.Taken Changchun city as the research object,the article explore the research method of identifying sites for sponge city which is based on the analysis of the sensitivity and suitability from the multi-level filtering perspective.And the sponge city construction method of Changchun has been explored basing on the results of comprehensive evaluation of sensitivity and suitability.Firstly,regarding the research method basing on the evaluation of risk and suitability in the land use planning under the threat of disaster and the research method basing on the evaluation of sensitivity and suitability in the ecological urban planning as the prototype of research methodology in this paper,the article constructs the research method of selecting sites for sponge space which is based on the evaluation of sensitivity and suitability from the multi-layer filtering perspective.Secondly,the article chooses TOPMODEL to analyze the hydrological sensitivity which is based on the calculation of topographic index,and selects the highest topographic index value(namely the area of more than 1.5 times the means)for hydrologic sensitive areas,that have the topographic index value of 11.42~16.93.And through the comparison of waterlogging point data and analysis results of hydrological sensitivity,the fitting degree proves the validity of the model which is as high as 89.4%.Thirdly,through reviewing the development process of connotation and objective of rain-flood management systems at home and abroad,three suitability evaluation factors of population density,spatial integration and urban green system are ultimately selected.Based on the multi-factor weightiness analysis of GIS,the article evaluates the suitability of sponge space and the study area is divided into 5 kinds of areas: most suitable areas,more suitable areas,suitable areas and so on.Finally,Based on the analysis of sensitivity and suitability,the article selects the areas with the highest sensitivity and the highest,higher suitability as the sites for sponge space,namely the area of comprehensive score 52 and 42.The selected sites for sponge space have a total of 1 675 cells,which occupy about 0.31% of the study area.And the construction method of realizing sponge city in Changchun has been explored from the aspects of construction of project library and determination of construction schedule.The study which constructs the research method of selecting sites for sponge space basing on the evaluation of sensitivity and suitability,enriches the research methodology for the study of sponge city and provides a new thinking and new perspective for the implementation of sponge city in urban planning.At the same time a visualization model of selecting sites for sponge space has been built,providing the city managers with scientific and quantitative analysis.