SSI1 - Soil Salinity Index-1

Waterlogging and subsequent salinization are a commonly land degradation processes taking place in irrigated fields in arid and semi-arid countries, in addition to soil erosion by wind and water. Wherever irrigation is used and in arid and semi-arid climates, soil salinization is a regular occurrence. Studies of the spatial extent, size, and temporal behavior of lands affected by these processes have been effectively conducted using remote sensing data (Khan et al.,2001)

In his study (Elhag, 2016) analysed different  methods employing remote sensing to measure soil salinity, developed through several academic studies. Thematic Mapper (TM), Enhanced Thematic Mapper (ETM+), and Operational Land Imager (OLI-8) pictures from Landsat were the most commonly utilized remote sensing data for mapping soil salinity. Due to the diversity of the research area and/or sensors, several algorithms for determining and mapping soil salinity were created. There have been numerous attempts to find salt-affected soil using remote sensing data and associated methods. Based on the unique reactions of salty soils to different spectral bands, soil salinity indices are primarily tuned to detect salt mineral in soils. By utilizing several soil salinity equations, it is possible to obtain sufficient estimates of soil salinity on a broad scale using remote sensing data.

The purpose of these indicators is to identify salinised soils and distinguish them from non-salinised soils in order to make nature-based solutions more effective when applied

Higher values indicate higher salinity and low values indicate lower salinity.

Generic Formula

Formula by Sentinel-2 bands 

References

• Khan, N. M., & Sato, Y. (2001, July). Environmental land degradation assessment in semi-arid Indus basin area using IRS-1B LISS-II data. In IGARSS 2001. Scanning the Present and Resolving the Future. Proceedings. IEEE 2001 International Geoscience and Remote Sensing Symposium (Cat. No. 01CH37217) (Vol. 5, pp. 2100-2102). IEEE.