A Study On The Restoration Of The Xuanwu Lake Basin With The Layout Of Green Space

People cannot live without water,but the construction of increasingly dense cities has brought about contradictions between urban development and urban water systems.Roads and buildings occupy space in urban water systems,causing droughts and floods.Although the traditional irrigation and transportation functions of the urban water system have gradually weakened,in the context of creating an ecologically livable city,the more prominent role of the urban water system is reflected in the ecological function and landscape value.Therefore,it is of great practical significance to refocus on the living space of urban water systems.At present,there is no precedent for the implementation of river basin water system restoration in urban dense areas.However,compared with the urban process in developed countries,the restoration of important water systems in cities is one of the trends of future urban development,and it also conforms to the main theme of the country’s emphasis on ecological civilization construction.The water system of the Xuanwu Lake Basin is the main water system in the main city of Nanjing.Xuanwu Lake is the largest lake in the city.This article takes the Xuanwu Lake Basin as the research object and intends to explore the strategy of the river system restoration from the perspective of the river basin planning.This research starts with practical problems,on the basis of combing theoretical knowledge,through data analysis and practical operations,to explore ways to improve the natural surface water catchment of lake basins in urban built-up areas.In terms of research methods,tools such as ArcGIS10.5 software platform,SWMM hydrological model,Fragstats4.2 software,ENVI5.3 software and other tools were comprehensively used to quantitatively analyze the green areas and water systems in the study area,especially through the establishment of hydrological models.The inflow of various rivers and the total inflow of Xuanwu Lake.Based on the analysis of the current situation of the Xuanwu Lake Basin,the problem of surface confluence in the watershed was discovered and proposed.From the perspective of planning,the approach of watershed restoration was considered and analyzed,and the idea of adding new rivers and green spaces in the area where surface runoff was blocked was proposed.Finally,on the basis of quantitative research,the priority of newlyadded rivers or green areas in different regions of the watershed is evaluated,and a comprehensive plan for water system restoration is proposed accordingly,which can provide a reference for gradually carrying out watershed water system restoration in a planned manner.The full text is divided into five chapters:The first chapter is an introduction,which mainly introduces the research background,basic concepts,research objects and research framework of this subject,summarizes the progress of domestic and foreign water system restoration research,and clarifies the research purpose and significance.Chapter 2 Theoretical research on water system restoration is the theoretical basis of the study.It sorts out the types and measures of water system restoration,expounds the relationship and role of green space and water systems in cities,and introduces the research methods and research tools that will be used in this article.The third chapter analyzes the basic situation in the study area,combined with the field survey data,has a more comprehensive understanding of the underlying surface and confluence of the Xuanwu Lake Basin.This chapter first summarizes the historical changes of the water system pattern in the study area and summarizes the causes of the water system degradation in the Xuanwu Lake Basin.Then through ArcGIS10.5,ENVI5.3 and Fragstats4.2 and other software for visual analysis of building layout,land use,green land and water system layout.Finally,a SWMM model is established based on the underlying surface data to quantify the watershed confluence.The fourth chapter first establishes the framework of river basin water system restoration.Based on the ArcGIS10.5 software platform,based on the DEM digital elevation model and current river channels,the problem of surface confluence of the river basin is analyzed,and the idea of relieving blocked water points is proposed,including new river channels and new Two types of green areas are added.SWMM model and ArcGIS10.5 software are used to analyze and evaluate the feasibility and priority of restoration in each area according to the current conditions.Finally,a comprehensive strategy for river basin water system restoration is obtained,and the benefits of this strategy are quantified.The fifth chapter summarizes the research,clarifies the innovation of the research,and puts forward the prospect of future research ideas.