Predicting the spatial distribution of salt-affected soil using Sentinel-2 in coastal area of Demak Regency

The distribution of salt-affected soil in Indonesia is difficult to locate because there are no main characteristics such as soil parent material, climate type, and evaporation rate. This study aimed to assess the spatial distribution of salt-affected soil in coastal area of Demak Regency using several salinity indices of Sentinel-2. Salt-affected soil distribution was identified by regressing electrical conductivity of soil samples with normalized difference salinity index (NDSI), normalized difference index (NDI), and salinity index (SI). A total of 30 soil samples taken from the coastal area of Demak Regency was examined for their electrical conductivity values to be used as training samples. The result showed that NDSI was more sensitive in mapping salt-affected soil with coefficient of determination of 0.23, standard error of estimate of 1.47 dS/m, and RMSE of 1.42 dS/m. The salt-affected soil distribution map indicated that electrical conductivity values in coastal area were higher compared to inland area with electrical conductivity ranged from 0 to 7.98 dS/m. © 2025 Institute of Physics Publishing. All rights reserved.