Change detection analysis of surface water bodies using pixel-based model in Jammu district, India

This study investigates the spatiotemporal dynamics of surface water bodies in Jammu District, India, from 2000 to 2020, utilizing a pixel-based model with Landsat time-series data. The research employs the Normalized Difference Water Index (NDWI) and the Automated Water Extraction Index (AWEI) to quantify changes in water body extent, revealing a significant decline across the district. Approximately 18–20 km² of water bodies were lost, primarily due to rapid urbanization, intensified agricultural practices, and climatic variability, including altered precipitation patterns. In contrast, only 12–13 km² of new water bodies were accreted, indicating limited expansion. Notable fragmentation and desiccation were observed, particularly in the northern and central regions, where ponds, lakes, and riverine networks have diminished, highlighting a critical hydrological imbalance. Both NDWI and AWEI demonstrated high accuracy (above 85%), with AWEI excelling in urban and shadowed environments due to its multi-band approach. Spatial distribution maps and temporal change detection highlight a consistent reduction in water body coverage, driven by anthropogenic pressures such as groundwater over-extraction, pollution, and land-use changes, alongside natural factors like reduced monsoon intensity. These findings underscore the urgent need for integrated water resource management and sustainable land-use planning to mitigate further degradation. By providing a detailed assessment of water body changes in a semi-arid region, this study offers critical insights for policymakers and lays the groundwork for geographically targeted conservation strategies to preserve Jammu’s hydrological balance.