This research investigates the spatiotemporal dynamics of shoreline change and associated population impacts in deltaic Bangladesh. This region is among the world’s most dynamic deltas due to monsoon precipitation that drives tremendous discharge and sediment volumes from the Ganges–Brahmaputra–Meghna drainage basin. Theoretically, it draws on the concept of adaptive cycles that theorizes systems transitioning through phases of growth, conservation, release (collapse), and reorganization, with a focus on the cycle’s release (collapse) phase and coupled linkages between the natural system of shoreline change and social system of household behavior. We use Landsat imagery to produce and describe a thirty-year record of shoreline change for an 80-km stretch of the Lower Meghna estuary. Household survey data characterized population impacts and risk perception for a subregion with high erosion rates. Results identified significant space–time differences and patterns of shoreline change and population impacts consistent with the adaptive cycle. North, central, and south regions exhibited statistically significant differences in space–time patterns of shoreline change. Substantial numbers of households reported displacement due to riverbank erosion and high levels of experience and worry about future displacement. Results demonstrate how geospatial analysis of a multidecade record of shoreline change along with analysis of household survey data can identify regions most vulnerable to riverbank erosion with implications to inform mitigation and adaptation. This work adds empirical demonstration of coupled adaptive cycles to the literature. Limitations and complexities of the adaptive cycle framework are discussed.

这项研究调查了三角洲孟加拉国海岸线变化的时空动态及相关的人口影响。由于季风降水，该地区是世界上最有活力的三角洲之一，它驱使恒河-布拉马普特拉-梅格纳流域的水和泥沙大量积聚。从理论上讲，它采用了适应性循环的概念，该理论对系统在生长，保护，释放（崩溃）和重组阶段的过渡进行理论化处理，重点是循环的释放（崩溃）阶段以及海岸线自然系统之间的耦合关系。和家庭行为的社会制度。我们使用Landsat影像制作并描述了下梅格纳河口一段80公里长的海岸线变化的30年记录。家庭调查数据描述了侵蚀率高的次区域的人口影响和风险感知。结果确定了明显的时空差异，海岸线变化的模式以及与适应性周期一致的人口影响。北部，中部和南部地区在海岸线变化的时空模式上显示出统计学上的显着差异。大量家庭报告由于河岸侵蚀和高水平的经验而流离失所，并对未来的流离失所表示担忧。结果表明，对海岸线变化的数十年记录进行地理空间分析以及对住户调查数据的分析如何能够确定最容易受到河岸侵蚀的地区，从而为缓解和适应提供信息。这项工作在文献中增加了耦合适应性循环的经验论证。讨论了自适应循环框架的局限性和复杂性。