Study On Urban Green Space System Planning Based On Ecological Sensitivity

China's reform and opening up has made remarkable achievements and development in many fields.Behind the fast growth of the economy,a series of disasters have been caused,such as soil pollution,air pollution,water quality deterioration,forest and grassland degradation,which seriously affect the ecological environment and human settlements.Green space has the function of purifying air,water body and improving microclimate,so it is more and more important in ecological construction.At present,the construction of urban green space in China lacks scientific theoretical basis and technical guidance,lacks a complete theoretical system,meanwhile,is in a weak position in the construction of ecological civilization.Guided by the theory of landscape ecology,this paper conducts ecological sensitivity analysis of the research area through GIS technology,which guides the planning of urban green space system based on the evaluation results,and finally completes the urban green space system planning with Shuidong Town as an example.The purpose of this paper is to find new planning ideas and methods for the planning of urban green space system,to promote the stability of urban ecosystem and to create a high quality human settlement environment.The main findings are as follows.(1)The connotation of urban green space system and ecological sensitivity evaluation is defined,and the related research trends and practical applications are analyzed,and the different methods of ecological sensitivity evaluation are expounded.The evaluation method of this study is space superposition analysis combined with comprehensive evaluation.(2)The basic data of Shuidong Town is studied and analyzed,and the database of Shuidong Town area based on GIS is established by visual interpretation combined with field investigation.Six ecological sensitivity factors,such as elevation,slope,water buffer,construction land,traffic land and land use type,were selected as evaluation indexes,and the ecological sensitivity evaluation system was constructed by combining expert scoring method and AHP.Based on the results of single factor evaluation,the comprehensive ecological sensitivity assessment was completed by using the weighted superposition method.According to the evaluation results,the study was divided into high sensitive area,moderate sensitive area,low sensitive area and insensitive area,and the area ratio was 15.24,respectively 59.15%,19.34% and 6.26%.(3)According to the evaluation results,the corresponding suggestions for land use and green space construction are put forward for different sensitive areas,and the green space network layout structure of "one core,one axis,two corridors,four horizontal,four vertical and multi-point" is established in combination with the traffic corridors and river systems in the region.The spatial layout structure of multi-point ecological green space is planned from three aspects of macroscopic,meso and micro-level to the green space system of Shuidong Town.