الفهرس 
CHAPTER 1:INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The Nile Basin, with the world’s longest river (6,700 km) is shared among eleven countries. The area of the basin is about 3.3 million km2. It stretches over different geographical, climatological and topographical regions. The climate and vegetation cover in the basin are closely correlated with the amount of precipitation, which decreases from above 1,000 mm/yr in the southern part to virtually zero in the northern part crossing the Sahara Desert. The precipitation and river-flow also encompasses sharp seasonal variability. The Spatial variability of evapotranspiration shows opposite trends to precipitation, i.e., increases in northward direction. The relative contribution to the mean annual Nile flow at Aswan of 84 billion m3 is approximately 4/7 from the Blue Nile, 2/7 from the White Nile (of which 1/7 is from the Sobat), and 1/7 from the Atbara River, i.e., the Ethiopian catchments (Sobat, Blue Nile and Atbara River) contribute to about 6/7 of the Nile water resources at Aswan.
The main objective of this study is to study the effect of the proposed dams on the yearly income of the basin using RIBASIM model as a decision support tool for water resources planning so as management and due to the significance of the Nile together with the impacts of population growth so as economic expansion. RIBASIM model was used to study the effect of some proposed dams on the Upper Nile basin. The model was set up Chapter 5 Conclusion and Recommendations 108 using readily available input data which includes river basin network schematization, hydrologic data and model data characterizing each node and the links. The model calibration was conducted using annually volume-discharge of the Blue Nile Basin. Relationships were applied using the yearly incomes to quantify the outflow from the
Blue Nile. The performance of the calibrated model was assessed with different techniques. A reasonable agreement was observed in the annual water balances and hydrograph shapes. Accordingly, the model was used for further analysis of the whole Nile basin and elemental sub-basins related to future trends of the main river flow and its hydrological components. Different scenarios were designed and the expected effects of constructing the proposed dams on the yearly income of the different subbasins of the Nile were calculated based on a selected representative year.
The results showed that the yearly income of Atbara, Blue Nile and main Nile basins were decreased with the construction of the proposed dams. Meanwhile, Sobat basin’s yearly income increased with the construction of the basin’s proposed dams.