Transforming the Floodplain: Agricultural Encroachment and Landscape Change in the Northwestern Ganges‐Padma Basin

The Ganges‐Padma floodplain of Bangladesh is a highly productive agricultural region critical to national food security and rural livelihoods. Over the past three decades, this fertile landscape has experienced significant land use and land cover (LULC) changes, particularly the expansion of agricultural land. This study analyses the spatial and temporal dynamics of such changes across six floodplain districts, namely Kushtia, Pabna, Rajbari, Chapai Nawabganj, Natore and Rajshahi from 1990 to 2023. Using Landsat imagery and a Random Forest classifier in Google Earth Engine, LULC maps were generated for five time points, achieving overall accuracies of 93%–99% and Cohen's kappa of 0.91–0.99. Findings reveal a net agricultural land gain of 771.70 km 2 , primarily at the expense of water bodies (−634.23 km 2 ) and vegetation cover (−224.71 km 2 ). Change detection and transition‐flow analyses show that wetlands and vegetated areas were the main sources of new cropland, driven by population growth, rising food demand and supportive agricultural policies. Built‐up areas also expanded, though to a lesser extent. While agricultural growth supports food production, it has contributed to wetland degradation, biodiversity loss and heightened climate vulnerability. These trends underscore the urgent need for integrated land management strategies that balance agricultural expansion with ecological sustainability. The study offers critical insights for policymakers and planners aiming to promote sustainable land use in deltaic and floodplain regions.