Monitoring Water Spread and Aquatic Vegetation using Spectral Indices in Nalsarovar, Gujarat State-India

Nalsarovar Bird Sanctuary, a natural freshwater lake (a relict sea) that is the largest wetland in Thar Desert Bio-geographic Province and represents dynamic environment with salinity depth varying depending on rainfall. For maintaining ecological balance coastal inland environments, wetlands play an important role changes can be monitored using satellite remote sensing technique. The present study was carried out Landsat-7 TM (Feb-2002), Landsat-5 (Feb- 2009) Sentinel-2 multi-spectral data (Feb-2018) covering area Ahmedabad district. of 10 km buffer extracted from digital data. Various spectral indices like Normalized difference Vegetation Index (NDVI), Water (NDWI) Turbidity (NDTI) were generated for better identification delineation water body aquatic vegetation Nalsarovar. composite images these also to map monitor spread along land use classes mapped False Colour Composite (FCC) differed years. result indicates has changed 2002, 2009 2018 monsoon pattern during During drought year 2002 total precipitation very less resulting drastic reduction 146.81 ha 510.93 2018. change agriculture land, built-up, & increased barren salt affected decreased. clearly visible NDVI, NDWI NDTI different This gives clear idea detection monitoring two techniques image NDTI.