Remote estimation of water quality parameters of Himalayan lake (Kashmir) using Landsat 8 OLI imagery

Abstract

The overarching aim of this study was to derive simple and accurate algorithms for the retrieval of water quality parameters for the Wular Lake using Landsat 8 OLI satellite data. The water quality parameters include pH, COD, DO, alkalinity, hardness, chloride, TDS, total suspended solids (TSS), turbidity, electric conductivity and phosphate. Regression analysis was performed using atmospherically corrected true reflectance values of original OLI bands, images after applying enhancement techniques (NDVI, principal components) and the values of the water quality parameters at different sample locations to obtain the empirical relationship. Most of the parameters were well correlated with single OLI bands with R² greater than 0.5, whereas phosphate showed a good correlation with NDVI image. The parameters like pH and DO showed a good relation with the principal component I and IV, respectively. The high concentration of pH, COD, turbidity and TSS and low concentration of DO infers the anthropogenic impact on lake.

Keywords:

• Landsat 8 OLI
• regression models
• water quality parameters
• geospatial technique

Acknowledgement

The authors acknowledge the financial assistance provided by the DST INSPIRE to carry out current research work. The authors also acknowledge the help and assistance provided by the Office of the Assistant Executive Engineer PHE, Chemical/Water Quality Sub Division, Srinagar, J&K.