Geological suitability evaluation for sponge city construction of Zhengzhou

Natural background and geological conditions have important influence on the layout of low-impact development facilities in the sponge city planning and construction.Aiming at the 1945 km² sponge city planning area of Zhengzhou city, according to the functions of water storage, seepage and water purification to be achieved by the construction of sponge city, based on the analysis of surface vegetation, topographic slope, vadose zone and aquifer, the geological suitability evaluation system was constructed suitable for the construction of sponge city, and it was evaluated with the analytic hierarchy process.The results show that geologically suitable area accounts for 3.83% or the total planning area, good suitability area for 33.12%, moderately suitable area for 54.05%, and poor fit area for 9.00%.Among the 12 key construction areas of sponge city planned in Zhengzhou, 2 cover unsuitable construction areas, which are distributed in the northwest of Longhu and Shuanghe Lake.There are natural conditions for building sponge city in Air Harbour.It is suggested to plan key sponge construction area around the Donghu ecological node.The evaluation result of geological suitability of sponge city construction is of reference significance to the planning and construction of sponge city in Zhengzhou.