Research on Surface Soil Stripping and Reuse in Shanghai Urban Green Space Landscape Renovation Area

Based on the renovation and expansion project of the northern area of Shanghai Botanical Garden,soil samples were taken from green spaces within the renovation area in 2021.The depths of soil sampling were stratificated as follows:0 to 20,20 to 40,40 to 60,and 60 to 100 cm.Soil pH,EC,organic matter,available nitrogen,available phosphorus,available potassium,as well as key soil fertility indicators such as soil bulk density,porosity,and microbial diversity were measured.The research results indicated that the pH and bulk density of 0—60 cm soil exceed the requirements of the Green Planting Soil standard,while only available phosphorus and available potassium meet the standard requirements of 60—100 cm soil.The principal component analysis method was used to evaluate the comprehensive fertility of each soil,and the results showed that the comprehensive fertility of the soil showed a decreasing trend with the increase of depth.The comprehensive results indicate that 0—60 cm soil can be directly peeled off as green planting soil,and 60—100 cm soil can be used as subsoil for terrain construction.The research results can provide reference for the classification evaluation and reuse of peelable topsoil in urban green space landscape renovation areas.