Research On The Planning And Design Of Small And Medium Scale Rainwater Harvesting Green Space In The Semiarid And Wet Areas Of Northwest China

Rapid urbanization has led to a sharp increase in impermeable pavement,and the contradiction between urban pipe network and rainwater runoff is increasingly prominent.In this context,China has vigorously promoted the construction of Sponge city,which has alleviated the urban rain flood problem to a certain extent.However,some sponge projects pay too much attention to engineering technology while ignoring the landscape of the site during the landing process,or too much emphasis on the landscape of the site ignores the rainwater function of the green space as a "natural Cavernous tissue",and does not fully consider the integration and balance between the rainwater system and landscape construction within the site,resulting in inadequate rainwater management or unsustainable landscape and other issues.As the main implementation carrier of Sponge city construction,rainwater harvesting green space can achieve a relative balance between rainwater system and landscape construction,which plays an important role in alleviating the rainwater problem of Urban green space and improving the urban landscape style.Therefore,this paper mainly studies the planning and design steps,rainwater system construction,rainwater landscape construction,etc.of rainwater harvesting green space.This article takes rainwater harvesting green spaces as the research object,and explores the planning and design methods of small and medium-sized rainwater harvesting green spaces with the direction of rainwater system and landscape creation.Firstly,based on the typical climate of the semi dry and humid northwest region,a survey was conducted on the rainwater harvesting green spaces in Xixian New Area,and specific problems were identified through horizontal comparative analysis;Secondly,based on the relevant principles of rainwater descent and collection,simulate the natural rainwater circulation process,and scientifically construct a rainwater management system.Specifically,starting from dividing the catchment area,regulating rainwater runoff,and setting storage points,the optimal rainwater spatial placement and rainwater facility layout can be obtained.At the same time,calculate and design the storage capacity based on the annual runoff total control rate,further calculate the scale of rainwater facilities,and solve the problem of inadequate rainwater management on the site;Finally,from the perspective of the four landscape elements of space,facilities,plants,and functions,the rainwater system is deeply integrated with landscape creation.Specifically,detailed research is carried out from the aspects of vertical terrain design,road and square planning,facility optimization and selection,interception plant landscape creation,and improvement of green space service functions,in order to find a balance between the rainwater system and landscape creation,Solve the problem of disconnection between rainwater system and landscape design in rainwater harvesting green spaces.Finally,it presents Ecotype rainwater harvesting green space that can not only collect and treat rainwater runoff,but also improve the landscape effect,while providing sustainable urban public activity space.Through the above research,the planning and design steps of small and medium-sized rainwater harvesting green space in the northwest semi dry and wet areas are obtained,and the landscape approach is used to improve and optimize the rainwater management process of rainwater harvesting green space,so as to solve the rainwater problem of Urban green space in the way of landscape presentation,and then alleviate the urban rain flood.Finally,the paper takes Xianyang Vocational and Technical College as a case study to construct a scientific and reasonable rainwater system from the perspectives of rainwater management organization,rainwater facility design,and total runoff calculation,in order to improve the current rainwater waterlogging problem on the campus.In addition,on the basis of a complete rainwater system,landscape construction is carried out in conjunction with the surrounding environment of the site.Specifically,the integration of the rainwater system and the site landscape is strengthened from the aspects of vertical terrain,road renovation,square design,and intercepted plant landscape creation.A sustainable rainwater harvesting green space landscape with rainwater aquatic functions is designed,providing reference and reference for the planning and design of rainwater harvesting green spaces in other cities in the semi dry and humid northwest region,At the same time,we will further develop and improve the technical means of Urban green space to deal with rainwater problems.