Soil Salinity Mapping and Evaluation based on Normalized Difference Salinity Index a Case of Daunt Tahsil, Pune District, Maharashtra

Soil salinization is a severe problem in the present-day context, particularly for the arid and semi-arid regions of the World. The primary causes of increasing soil salinity are excessive and improper irrigation practices, the overuse of chemical fertilizers, and a monocropping pattern of water-intensive cash crops. The study area selected for the present research work is Daund Tahsil in Pune District of Maharashtra. Soil salinity is mainly observed in continuous patches, particularly in the north-western part of the study area. The present research aims to delineate areas covered by saline soils. Remotely sensed data in the form of satellite imageries and DIP (Digital Image Processing) techniques are highly effective in the generation of various salinity indices and thereby the detection of soil salinity. Satellite imageries can also be used to monitor both spatial and temporal variations of soil salinity. A LANDSAT 8 OLI (Operational Land Imager Sensor) satellite image (2017) was used for estimating the NDSI (Normalized Difference Salinity Index) and preparing the soil salinity map of Daund Tahsil. The NDSI considers the Near Infrared (NIR) band and Red (R) band for estimating soil salinity. According to the calculated NDSI, the study area has been categorized into four classes, viz., highly saline, moderately saline, slightly saline, and non-saline land. The highly saline land covered a major part of the study area among saline land classes.