物理気候因子、ファジーロジック、GISを用いたザンベジ川上流域の地下水干ばつ脆弱性マッピングへの統合的アプローチ

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Provides a novel integrated framework for groundwater drought vulnerability assessment that can be adapted to other regions.

🏢実務担当者:Offers a practical mapping tool for water resource managers to prioritize interventions in drought-prone areas.

🏛政策担当者:Highlights the need for adaptive groundwater governance in transboundary basins facing climate change.

ABSTRACT Groundwater plays a critical buffering role against climate variability in semi-arid regions, yet its resilience to increasing drought stress remains poorly quantified in many trans-boundary African basins. The UZRB (Upper Zambezi River Basin), spanning Angola, Zambia, Namibia, and Botswana, is increasingly exposed to climate-change-induced drought, compounded by hydrogeological constraints and growing anthropogenic pressures. This study develops a spatially explicit GVDM (Groundwater Vulnerability to Drought Map) for the UZRB using an integrated fuzzy logic-based GIS (Geographic Information System) framework that explicitly accounts for exposure, sensitivity, and adaptive capacity dimensions of groundwater vulnerability. Twelve physically and socio-environmentally relevant indicators were derived primarily from remotely sensed and global datasets to address the scarcity of in-situ observations. Exposure was characterized using long-term precipitation (CHIRPS), evapotranspiration (WaPOR), and population density (WorldPop). Sensitivity was assessed through depth to groundwater, groundwater recharge and storage anomalies (GLDAS/GRACE), aquifer productivity, soil type (FAO), and topographic/aspect attributes (Copernicus DEM). Adaptive capacity was evaluated using groundwater storage anomalies, drainage density and lineament density. All indicators were normalized, fuzzified using expert-informed membership functions, and integrated using a fuzzy GAMMA overlay operator. Vulnerability classes were delineated using percentile-based defuzzification thresholds. Results reveal pronounced spatial heterogeneity in groundwater drought vulnerability across the basin. High vulnerability is concentrated in the southern and southeastern UZRB, where low precipitation, persistently high evapotranspiration, shallow groundwater tables, limited recharge potential, and increasing population pressure converge. In contrast, the northern and northwestern regions exhibit lower vulnerability due to comparatively higher rainfall, deeper aquifers, and more favourable hydrogeological conditions. Model validation using the SCWBI (Standardized Climatic Water Balance Index) for 2009–2023 demonstrates strong spatial agreement between high groundwater vulnerability zones and areas experiencing moderate to severe climatic water deficits, confirming the robustness of the proposed framework. This study represents the first basin-wide, fuzzy logic-based groundwater drought vulnerability assessment for the UZRB that integrates physical, climatic, and socio-economic drivers within a unified framework. The resulting GVDMs provide a practical decision-support tool for drought risk reduction, adaptive groundwater governance, and sustainable water-resources planning in data-scarce, climate-vulnerable trans-boundary basins across Southern Africa and beyond.

• semanticscholar https://www.tandfonline.com/doi/pdf/10.1080/19475683.2026.2693182?needAccess=truefirst seen 2026-09-06 05:47:27 · last seen 2026-09-21 05:17:13