Long-Term Vegetation Change in Hadejia-Nguru Wetlands: Drivers and Conservation Implications

Long-term vegetation change in the Hadejia-Nguru Wetlands of Jigawa State, within Nigeria's North West geopolitical zone, has significant implications for the wetland's continued function as a biodiversity hotspot, Ramsar site, and ecosystem service provider. Despite the wetland's international conservation status, systematic long-term vegetation monitoring data are scarce. This study analyzes vegetation change in the Hadejia-Nguru Wetlands over a 15-year period (2008 to 2023) using multi-temporal Landsat imagery supplemented by field-based vegetation surveys and interviews with long-term community residents. Supervised classification of satellite imagery was used to track changes in open water, emergent macrophyte, floodplain grassland, and riparian forest cover. Field surveys recorded current species composition and structure at 40 vegetation plots within representative wetland zones. Results indicate a 31 percent contraction in permanent open water and a 24 percent reduction in emergent macrophyte coverage over the study period. Floodplain grassland has partially replaced former wetland zones in areas experiencing reduced inundation frequency. Community residents confirm perceptions of vegetation change consistent with remote sensing findings. Water flow reduction upstream driven by increased irrigation abstraction is identified as the primary vegetation change driver. The study recommends trans-boundary water governance mechanisms for the Komadugu-Yobe River basin, investment in flow restoration modeling, and seasonal vegetation monitoring protocols. Keywords: vegetation change, Hadejia-Nguru, remote sensing, North West Nigeria, wetland hydrology