Study On Sponge Planning And Design Of Xihai Town In Haibei Prefecture From The Perspective Of Ecohydrology

The 18 th National Congress of the Communist Party of China proposed an ecological civilization construction strategy,requiring urban construction and operation in the new era to adhere to the path of green development,circular development,and low-carbon development.The "Ecological Protection and High-Quality Development Strategy of the Yellow River Basin" is one of the major strategic measures of the country’s ecological civilization construction,highlighting the implementation of ecological protection,restoration and construction projects in the water conservation area of the upper reaches of the Yellow River.The implementation of sponge construction in the ecologically sensitive water conservation area of the upper reaches of the Yellow River is one of the important means to alleviate the interference of urban development on the ecohydrological system,protect the water ecological environment of the river basin,and promote the green development of cities and towns.Xihai Town,as the first batch of demonstration towns of plateau beautiful towns jointly built by the provinces and ministries in the upper reaches of the Yellow River,undertakes the important responsibility of building a new pattern of urban green development and creating a new model of ecologically livable plateau beautiful towns.However,its current weak The construction foundation and lagging planning and design have severely restricted the realization of urban development goals.Facing the fragile regional ecohydrological environment and the lagging urban development status,the existing sponge city experience cannot effectively guide the construction of sponge city in Xihai Town.Therefore,from the perspective of ecohydrology,this paper launches a research on sponge planning and design suitable for the ecohydrological environment and urban construction of Xihai Town,and provides ideas and approaches for urban green ecological construction.Firstly,the spatial construction characteristics and ecohydrological characteristics of Xihai town were analyzed and summarized,the main factors affecting the ecohydrological process in the urban spatial construction were studied,and the appropriate construction target of sponge town was proposed.Secondly,the sponging technology suitable for the natural ecological environment and the development and construction level of Xihai Town was explored to provide a choice for the appropriate sponging planning and design.Thirdly,the direction and content of hydrological process optimization are proposed.The underlying surface elements and spatial composition that interfere with the hydrological process optimization of the plot are adjusted through sponging design.The sponging contents are selected and combined in the technical integration to realize the translation from ecohydrological theory to sponging technology.Finally,based on the suitable sponging path,the appropriate sponging planning was carried out for Xihai Town,and the SWMM model was used to verify the sponging construction effect,so as to ensure the maximization of the comprehensive benefits of the urban sponging construction.The results show that the building density and the amount of impervious underlying surface in Xihai town are the main factors affecting the evaporation and runoff of the ecohydrological process.Therefore,it is proposed that the construction goal of the suitable sponge town in Xihai town should be to restore the natural cycle of the hydrological process as the goal,and the reconstruction of the underlying surface is the key point of planning and design.Secondly,sponge facilities with mature application were selected to screen out the sponge facilities suitable for the climate characteristics,ecosystem characteristics,human resources characteristics and operation and maintenance characteristics of Xihai Town,and the adaptive technology integration was formed.Then,according to the runoff of underlying surface,Xihai Town was divided into four plot types: A,B,C and D,and typical plots were extracted.Four optimization directions of "storage","seepage","storage" and "transport" were proposed respectively,and the sponging design of typical plots was carried out based on this.According to the design content,the appropriate facilities were selected in the integration of adaptive technology to complete the sponging layout of each typical plot,and the corresponding planning and control requirements were put forward.The SWMM model was used to verify that the sponging benefits of each typical plot were maximized.Finally,in the typical field of sponge path to build,on the basis of the western town of rainwater unit division,from the urban land use,land underlying surface and three aspects put forward the planning control requirements,technical facilities using SWMM non-spot model to control the amount of runoff before and after the sponge,rainwater storing recycle,to simulate the situation and runoff pollution reduction Verify that the sponging planning has achieved the maximum benefit,and put forward planning management and practical guarantee measures to ensure the final sponging.