Sagar Island is a very popular pilgrimage destination located in the western part of Indian Sundarbans. This study employs Digital Shoreline Analysis System (DSAS) extension tool in ArcGIS platform to study and analyse the shoreline dynamics of Sagar Island by utilizing satellite images extending 40 years (1975–2015). 44 transects with 100 m spacing were laid and divided into six littoral cells (LCs). End Point Rate (EPR) and Linear Regression (LR) models were utilized to analyze the shoreline change patterns and also for predicting the future shoreline positions. It was observed that almost the entire southern portion of Sagar Island is susceptible to high rate of shoreline erosion. Most of the erosion occurred in Dhablat (LC 4 (a)) in the south eastern part at a rate of 11.695 ± 2.1 m/year. The mean shoreline change rate was also high in LC5 (±23.525 m/year). However, the overall shoreline change rate for the island was 4.94 m/year and uncertainty of total shoreline change rate was ±4.4 m/year. The study shows the usefulness of DSAS as a scientific tool for shoreline change studies and highlights state of erosion in the study area.

中文翻译：

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印度西孟加拉邦萨加尔岛海岸线迁移的时空模拟

萨加尔岛（Sagar Island）是位于印度Sundarbans西部的非常受欢迎的朝圣目的地。本研究使用ArcGIS平台中的数字海岸线分析系统（DSAS）扩展工具，通过利用40年（1975年至2015年）的卫星图像来研究和分析萨加尔岛的海岸线动力学。铺设了间距为100 m的44个样带，并将其分成六个滨海单元（LC）。端点速率（EPR）和线性回归（LR）模型用于分析海岸线变化模式，并用于预测未来的海岸线位置。据观察，萨加尔岛几乎整个南部地区都容易遭受海岸线侵蚀。大部分侵蚀发生在东南部的Dhablat（LC 4（a）），速率为11.695±2.1 m /年。LC5的平均海岸线变化率也很高（±23.525 m /年）。但是，该岛的总体海岸线变化率为4.94 m /年，总海岸线变化率的不确定度为±4.4 m /年。该研究表明DSAS作为海岸线变化研究的科学工具的有用性，并强调了研究区域的侵蚀状态。