Assessing Spatiotemporal Change in Land Cover and Total Dissolved Solids Concentration Using Remote Sensing Data

In the recent past, Pakistan's economy has suffered due to a shortage of electric power. To shorten the production and demand gap, coal reserves in the Thar region of Pakistan are being utilized. During the process of mining, a huge quantity of saline water is being pumped from the mining site to a natural depression called Gorano Dam. This study examines the impact of saline water on land cover in the area. Two scenarios including pre-disposal conditions (February 2017) and existing conditions (February 2020) were compared. Sentinel-II images with a spatial resolution of 10 m were classified using the maximum likelihood supervised classification method. This study also determines the spatial and temporal variation of total dissolved solids (TDS) in the Gorano Dam. Water quality samples were collected to measure TDS. Landsat 8 OLI images were used to develop a linear regression equation between Band 5 reflectance and TDS measurements. Using the regression model, spatiotemporal maps of TDS were developed. The results revealed that the area covered by water in February 2020 was 1,233,100 m(2). After the creation of the dam, the area covered by barren land has decreased from 4,592,100 to 4,134,900 m(2) (9.96% decrease), and the area covered by vegetation has decreased from 3,682,400 to 1,906,500 m(2) (48.23% decrease). The coefficient of determination (R-2) for the multiple regression equation was 0.846. The study will help to understand the impacts of Gorano Dam on the land cover of the area and temporal change in TDS of the dam.