Tittle: Quantification of Historical and Future Loss of Different Landuse/ Landcover in Response to Erosion-Accretion: A DSAS-Based Approach for Future Predictions along the Purba Medinipur Coast, West Bengal

From the historic past the Purba Medinipur coastal region undergoes constant transformation due to its morpho-dynamic attributes and impact of human interventions. Predicting the loss of landuse/landcover along the Purba Medinipur coast is crucial for environmental conservation and sustainable development through safeguarding both humans and natural ecosystems of the region. The current study quantified the historical and future loss of different landuse/ landcover types in response to erosion-accretion along the Purba Medinipur coast. using digital shoreline analysis system (DSAS). Temporal multispectral data of TM, ETM + and OLI sensors of the years of 1991, 2001, 2011 and 2021 have been used here. Threshold method (NIR band) and remotely sensed indices (NDVI and NDWI) have been adopted to extract shoreline. Linear regarrison rate (LRR), Net shoreline movement (NSM) and End point rate (EPR) have been calculated to estimate the change rate. Finally, shoreline of the year of 2031 and 2041 have been predicted using beta shoreline forecast tool in ArcGIS. Predicted erosion is estimated to be 337.12 hectares in 2031 and 663.91 hectares in 2041. The study reveals that Digha, Mandarmoni and Bankiput areas are most susceptible to erosion. Subsequently, the agricultural land experienced the highest degree of loss (33.07%) followed by wetland (22.13%), vegetation (15.73%) and builtup area (9.97%). The study forecasts the highest loss in agricultural (33.80%) and barren land (31.76%) due to coastal erosion. Validation of the model has been done using RMSE (27.259 metre) and Kappa co-efficient (94.03%) which ensured that the predicted result is accurate and reliable.