Analyzing the hydrologic effects of region-wide land and water development interventions: a case study of the Upper Blue Nile basin

摘要: In the drylands of Upper Blue Nile basin, high climate variability and land degradation are rampant. To enhance adaptive capacity in region, various soil water conservation interventions have been implemented. Moreover, resources development schemes such as Grand Ethiopian Renaissance Dam should be implemented by 2025. We modeled effects these on surface runoff basin for both current future (2025) conditions, using coefficient method a spatially explicit approach. Under we observed spatial mean annual runoff. The northeastern Nile-1 sub-basin produces highest (391 mm or 10 × 109 m3), whereas northwestern Nile-2 lowest (178 0.2 m3). generates total volume 47.7 m3, which about 54 % comes from cultivated land. strong association between use topography masked direct effect rainfall By 2025, yield could decrease up to 38 if appropriate basin-wide However, full most physical structures will only last 1 2 years without regular maintenance. improved understanding dynamics basin’s hydrology provided present study help planners design management scenarios. Developing database remains important holistic impacts interventions.