Mapping and Monitoring Change Detection of High-Altitude Wetland Using Remote Sensing and GIS: A Case Study of Rara Wetland, Nepal

High-altitude wetlands (HAW) are essential for the environment as they mitigate climate impacts, facilitate water regulation and groundwater recharge, function as carbon sinks, and promote ecological stability. To protect it from disappearing, it is essential to map and monitor change detection to analyze the extent. However, research on monitoring HAWs remains limited in the world and gets very limited attention. This research uses Geographic Information System (GIS) and remote sensing techniques to analyze the change in Rara wetland extent from 2000 to 2020. We used the Shuttle Radar Topography (SRTM) digital elevation model to generate slope and Topographic Wetness Index (TWI) and Landsat 7 ETM+ images to derive normalized difference Vegetation Index (NDVI), Normalizing Difference Water Index (NDWI) and supervised classification for different years. Over the past two decades, 1.25% of the total area of Rara wetland has been lost at an annual rate of 0.997 hectares. It highlights the urgent necessity for conservation action. This study confirms that GIS and remote sensing effectively delineate, map, and assess wetland dynamics, offering essential insights for future conservation policies and strategies.