Relationship between water salinity and vegetation distribution in the Tiaozini reclamation area

To investigate the water and salt distribution, and explore the relationship between vegetation circles and soil water salinity conditions in the Tiaozini reclamation area of Dongtai, Jiangsu, a measurement and sampling campaign was conducted in a reclaimed zone used for wetland restoration in September 2019. Electrical resistivity tomography (2-D and 3-D) was conducted near the plant circles. Precipitation, surface water, soil profiles, and shallow groundwater samples were collected and analyzed for water and salt parameters as well as for D and ¹⁸O isotopic compositions. The results show that low resistivities and high salinity zones exist underneath the plant circles within 3 m of depth, and soil water salinity increases with the plant type, changing from the center of the circle to the outer area. Soil water salinity is an essential factor for the circular distribution of different plant types. Spatial variation of surface soil water salinity results from both precipitation infiltration and salt accumulation caused by evaporation. Soil salinity affects the distribution pattern of different plant types, while plants can also influence the salinity distribution by affecting the infiltration and evaporation processes.