DOCSLIB.ORG

The Impact of Soil Erosion in the Upper Blue Nile on Downstream Reservoir Sedimentation

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Impact of Soil Erosion in the Upper Blue Nile on Downstream Reservoir Sedimentation THE IMPACT OF SOIL EROSION IN THE UPPER BLUE NILE ON DOWNSTREAM RESERVOIR SEDIMENTATION THE IMPACT OF SOIL EROSION IN THE UPPER BLUE NILE ON DOWNSTREAM RESERVOIR SEDIMENTATION DISSERTATION Submitted in fulfilment of the requirements of the Board for Doctorates of Delft University of Technology and of the Academic Board of the UNESCO-IHE Institute for Water Education for the Degree of DOCTOR to be defended in public on 28 th October 2014 in Delft, The Netherlands by YASIR SALIH AHMED ALI born in Wad Medani, Sudan BSc Civil Engineering, University of Khartoum, Khartoum, Sudan MSc Water Management, Water Management and Irrigation Institute, University of Gezira, Wad Medani, Sudan MSc Water Science and Engineering ‘Hydraulic Engineering and River Basin Development’, UNESCO-IHE, Delft, the Netherlands This dissertation has been approved by the supervisors: Prof.dr.ir. A.E. Mynett Prof.dr. N.G. Wright Composition of the Doctoral Committee: Chairman: Rector Magnificus, DelftUniversity of Technology Vice-chairman: Rector, UNESCO-IHE Prof.dr.ir. A.E. Mynett UNESCO-IHE/ TU Delft, Promotor Prof.dr. N.G. Wright UNESCO-IHE/ University of Leeds, Promotor Prof.dr.ir. N.C. van de Giesen Delft University of Technology Dr.ir. A. Crosato UNESCO-IHE/ TU Delft Dr.ir. A.J.F. Hoitink Wageningen University Prof.dr. Y.A. Mohamed HRC, Sudan/UNESCO-IHE Prof.dr.ir. W.Uijttewaal Delft University of Technology, reserve member CRC Press/Balkema is an imprint of the Taylor & Francis Group, an informa business © 2014, Yasir Salih Ahmed Ali All rights reserved. No part of this publication or the information contained herein may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, by photocopying, recording or otherwise, without written prior permission from the publishers. Although all care is taken to ensure the integrity and quality of this publication and information herein, no responsibility is assumed by the publishers or the author for any damage to property or persons as a result of the operation or use of this publication and or the information contained herein. Published by: CRC Press/Balkema PO Box 11320, 2301 EH Leiden, The Netherlands e-mail: [email protected] www.crcpress.com – www.taylorandfrancis.co.uk ISBN 978-1-138-02742-8 (Taylor & Francis Group) To the memory of my lovely sister, Nada SUMMARY Population growth in the upper Blue Nile Basin led to fast land-use changes from natural forest to agricultural land, which resulted in speeding up the soil erosion processes. Soil erosion undesirably reduces soil fertility and hence the agricultural productivity upstream. Eroded sediment is transported to the lower Blue Nile Basin, where sedimentation occurs at many locations. In the reservoirs, sedimentation leads to serious reduction in storage capacity, causing hydropower generation problems and negative impacts on the socio-economic, environmental and ecological system. The sediment settling inside irrigation canals leads to water shortage and management difficulties. Sediment deposition in the main channel of the river raises the bed level and enhances flood risks. The Blue Nile River Basin is currently experiencing new developments, both in Ethiopia and Sudan. The Grand Ethiopia Renaissance Dam (GERD) is under construction about 30 km upstream of the Ethiopian-Sudanese border. Recently, the Roseires Dam located 110 km downstream the Ethiopian-Sudanese border has been heightened by 10 m, increasing the storage capacity of the reservoir by additional 3700 million m 3. Some dams are planned in Ethiopia for hydropower production. These developments will strongly affect the water resources and sediment deposition in the lower Blue Nile Basin. Sedimentation in the new reservoirs and in irrigation canals will depend on the operation of these dams, but the only effective solution to reduce the sedimentation problems is reducing the sediment input. This can be achieved by means of erosion control practices in the upper basin. For this, given the vastness of the upper basin, it is important to identify the areas where the largest amounts of sediment are produced. The main objective of this research is to identify these areas and quantify the amounts of sediment involved. This research investigates also the effects of the new developments on the sediment processes. Several knowledge gaps have been filled in by this research in order to fulfill the goals. Missing information comprised: Bathymetric and morphological data including river cross-sections, as well as river bed and bank material along the main river and tributaries. Hydrological data including flow discharges and sediment concentration. Water and sediment transport distribution along the river network at all flow conditions. History of sedimentation (including amounts) in the basin. Origin of the deposited sediment in the lower basin. Relation between land-use changes and sediment yield in the sub basins providing the largest amounts of sediment deposition in the lower basin. Extensive field surveys were conducted both in Ethiopia and Sudan as part of this study to bridge the knowledge gaps. The bed topography was measured at 26 cross sections along the Blue Nile River and major tributaries using an eco-sounder in Ethiopia and an Acoustic Doppler Current Profiler in Sudan. Soil samples were taken from the areas affected by erosion in the upper basin and from the bed and banks of the rivers. Suspended sediment samples were collected at several locations along the Blue Nile River and its tributaries, both in Ethiopia and Sudan. In addition, suspended sediment concentration was sampled on a daily basis near the Ethiopian- Sudanese border during the flood season for 4 years. The collected samples were analyzed at Addis Ababa University laboratory, the Hydraulics Research Station laboratory in Wad Medani and the Technical University of Delft. Annual flow discharge and sediment load balances were obtained by integrating the available and newly measured flow discharges, suspended sediment concentration and the results of numerical models using the Soil and Water Assessment Tool software (SWAT). The yearly sediment balances were estimated at several locations along the main river and the tributaries. Three regression approaches were used to determine the sediment loads from the rating curves derived from the measured data. These were developed using the linear and non-linear log-log regressions, while the statistical bias correction factor was used to improve the linear regression results. The water distribution along the entire river system was assessed in order to quantify the availability of the water resource at all seasons and flow conditions. A one- dimensional hydrodynamic model of the entire river network was developed including all known water uses for irrigation, as well as all major hydraulic structures and their operation rules using the Sobek software. The model was further used to study sediment transport via integration with the water quality module of the Delft3D software. This integrated model (Sobek Rural and Delft3D Delwaq) allowed simulating the morpholological processes along the Blue Nile River, from Lake Tana to Roseires Dam. The model was calibrated and validated based on the Roseires Reservoir historical bathymetric surveys, and the sediment concentrations measured at the Ethiopian-Sudanese border. The model was then run to predict the impact of Roseires Dam heightening and the construction of the Grand Ethiopian Renaissance Dam on sedimentation rates. The history of sedimentation inside Roseires Reservoir, the first sediment trap along the Blue Nile River, was studied by combining historical bathymetric data with the results of a quasi 3D morphodynamic model including vertical sorting (based on the Delft3D software). Selective sedimentation creates soil stratification inside the reservoir allowing for the recognition of specific wet or dry years. The most promising coring locations from where soil samples could be collected were identified by analyzing the results of the model, since the model allowed identifying the areas that were neither subject to net erosion nor to bar migration during the life span of the reservoir. A second measuring campaign took place at these locations to analyze the sediment deposited in the reservoir The origin of the sediment deposited in the reservoir was indentified based on the mineral characteristics of the material. X-Ray Diffraction laboratory analyses allowed assessing the mineral content in the sediment samples that were collected during the field campaigns from the eroded areas in the upper basins and from the deposited soil layers inside Roseires Reservoir. The integration of the results of the X-Ray Diffraction with a cluster analysis allowed identifying the source of the sediments deposited inside Roseires Reservoir. The results showed that the sub basins of Jemma, Didessa and South Gojam constitute the main sediment source areas. The implementation of erosion control practices can therefore start from these sub basins. The land use changes occurred in these sub basins in the last 40 years show that natural forest, woodland, wooded grassland and grassland decreased from more than 70% to less than 25% of the surface area. Instead, the cultivated area increased from 30% to more than 70% of the total surface area. Finally, model results showed that the annual sediment deposition inside the Renaissance Dam (under construction) will vary with time, with maximum
Load more

Recommended publications
  • Revision of the Genus Ficus L. (Moraceae) in Ethiopia (Primitiae Africanae Xi)
    582.635.34(63) MEDEDELINGEN LANDBOUWHOGESCHOOL WAGENINGEN • NEDERLAND • 79-3 (1979) REVISION OF THE GENUS FICUS L. (MORACEAE) IN ETHIOPIA (PRIMITIAE AFRICANAE XI) G. AWEKE Laboratory of Plant Taxonomy and Plant Geography, Agricultural University, Wageningen, The Netherlands Received l-IX-1978 Date of publication 27-4-1979 H. VEENMAN & ZONEN B.V.-WAGENINGEN-1979 BIBLIOTHEEK T)V'. CONTENTS page INTRODUCTION 1 General remarks 1 Uses, actual andpossible , of Ficus 1 Method andarrangemen t ofth e revision 2 FICUS L 4 KEY TOTH E FICUS SPECIES IN ETHIOPIA 6 ALPHABETICAL TREATMENT OFETHIOPIA N FICUS SPECIES 9 Ficus abutilifolia (MIQUEL)MIQUEL 9 capreaefolia DELILE 11 carica LINNAEUS 15 dicranostyla MILDBRAED ' 18 exasperata VAHL 21 glumosu DELILE 25 gnaphalocarpa (MIQUEL) A. RICHARD 29 hochstetteri (MIQUEL) A. RICHARD 33 lutea VAHL 37 mallotocarpa WARBURG 41 ovata VAHL 45 palmata FORSKÀL 48 platyphylla DELILE 54 populifolia VAHL 56 ruspolii WARBURG 60 salicifolia VAHL 62 sur FORSKÂL 66 sycomorus LINNAEUS 72 thonningi BLUME 78 vallis-choudae DELILE 84 vasta FORSKÂL 88 vogelii (MIQ.) MIQ 93 SOME NOTES ON FIGS AND FIG-WASPS IN ETHIOPIA 97 Infrageneric classification of Hewsaccordin gt o HUTCHINSON, related to wasp-genera ... 99 Fig-wasp species collected from Ethiopian figs (Agaonid associations known from extra- limitalsample sadde d inparentheses ) 99 REJECTED NAMES ORTAX A 103 SUMMARY 105 ACKNOWLEDGEMENTS 106 LITERATURE REFERENCES 108 INDEX 112 INTRODUCTION GENERAL REMARKS Ethiopia is as regards its wild and cultivated plants, a recognized centre of genetically important taxa. Among its economic resources, agriculture takes first place. For this reason, a thorough knowledge of the Ethiopian plant cover - its constituent taxa, their morphology, life-cycle, cytogenetics etc.
    [Show full text]
  • The Grand Ethiopian Renaissance Dam and Ethiopia's Succession in Hydro-Legal Prominence
    The Grand Ethiopian Renaissance Dam and Ethiopia’s Succession in Hydro-legal Prominence: A Script in Legal History of Diplomatic Confront (1957-2013) Tadesse Kassa Woldetsadik . Abstract This article argues that within the system of international law, while Ethiopia’s equitable right of access to resources of the Nile is recognized as a matter of settled principle, the law’s actual working is a coefficient of prior hydraulic measures adopted on the ground rather than mere articulation of legal norms, diplomatic civility or altercations. I also submit that the system of international law still remains vital in resolving transboundary water issues, and yet, the mechanics of law could not function optimally outside of power politic, diplomatic dexterity and sincere commitment to the fundamental values it upholds. In this light, and against a backdrop of Ethiopia’s relegated position in the second half of the twentieth century, the paper concludes that today the country’s relative renaissance in the Nile legal politics - which for the first time captured serious downstream interest in riparian negotiations - is attributed not to a change in the pertinence of the norms of international law nor to any altruistic revision of positions in the lower reaches of the river, but rather to its belated awakening in pursuing the Grand Ethiopian Renaissance Dam (GERD) as a national project of multifarious impact. Key terms The Grand Ethiopian Renaissance Dam, Nile water resources development, Nile, legal diplomacy, Ethiopia, Egypt, Sudan. DOI http://dx.doi.org/10.4314/mlr.v9i2.5 ___________ Introduction In an article published in Mizan 8(2) focusing on the legal history and diplomatic minutiae of the first half of the twentieth century (1902-1956), it was argued that the Anglo-Ethiopian Treaty of 1902 on the Blue Nile and the stream of negotiations conducted in the immediate aftermath in relation to the Lake Tana .
    [Show full text]
  • List of Rivers of Ethiopia
    Sl. No Name Location (Flowing into) Location (Lake) 1 Adar River (South Sudan) The Mediterranean 2 Akaki River Endorheic basins Afar Depression 3 Akobo River The Mediterranean 4 Ala River Endorheic basins Afar Depression 5 Alero River (or Alwero River) The Mediterranean 6 Angereb River (or Greater Angereb River) The Mediterranean 7 Ataba River The Mediterranean 8 Ataye River Endorheic basins Afar Depression 9 Atbarah River The Mediterranean 10 Awash River Endorheic basins Afar Depression 11 Balagas River The Mediterranean 12 Baro River The Mediterranean 13 Bashilo River The Mediterranean 14 Beles River The Mediterranean 15 Bilate River Endorheic basins Lake Abaya 16 Birbir River The Mediterranean 17 Blue Nile (or Abay River) The Mediterranean 18 Borkana River Endorheic basins Afar Depression 19 Checheho River The Mediterranean 20 Dabus River The Mediterranean 21 Daga River (Deqe Sonka Shet) The Mediterranean 22 Dawa River The Indian Ocean 23 Dechatu River Endorheic basins Afar Depression 24 Dembi River The Mediterranean 25 Denchya River Endorheic basins Lake Turkana 26 Didessa River The Mediterranean 27 Dinder River The Mediterranean 28 Dipa River The Mediterranean 29 Dungeta River The Indian Ocean 30 Durkham River Endorheic basins Afar Depression 31 Erer River The Indian Ocean 32 Fafen River (only reaches the Shebelle in times of flood) The Indian Ocean 33 Galetti River The Indian Ocean 34 Ganale Dorya River The Indian Ocean 35 Gebba River The Mediterranean 36 Germama River (or Kasam River) Endorheic basins Afar Depression 37 Gibe River
    [Show full text]
  • 2-Reem-Phd Thesis-Draft-21-2020-04-17-Final W
    Optimizing the Operation of a Multiple Reservoir System in the Eastern Nile Basin Considering Water and Sediment Fluxes Reem Fikri Mohamed Osman Digna OPTIMIZING THE OPERATION OF A MULTIPLE RESERVOIR SYSTEM IN THE EASTERN NILE BASIN CONSIDERING WATER AND SEDIMENT FLUXES Reem Fikri Mohamed Osman Digna OPTIMIZING THE OPERATION OF A MULTIPLE RESERVOIR SYSTEM IN THE EASTERN NILE BASIN CONSIDERING WATER AND SEDIMENT FLUXES DISSERTATION Submitted in fulfillment of the requirements of the Board for Doctorates of Delft University of Technology and of the Academic Board of the IHE Delft Institute for Water Education for the Degree of DOCTOR to be defended in public on Tuesday 26 May 2020, at 15:00 hours in Delft, the Netherlands by Reem Fikri Mohamed Osman DIGNA Master of Science in Water Resources Engineering, University of Khartoum born in Khartoum, Sudan iii This dissertation has been approved by the promotors: Prof.dr.ir. P. van der Zaag IHE Delft / TU Delft Prof.dr. S. Uhlenbrook IHE Delft / TU Delft and copromotor Dr. Y. A. Mohamed IHE Delft Composition of the doctoral committee: Rector Magnificus TU Delft Chairman Rector IHE Delft Vice-Chairman Prof. dr.ir. P. van der Zaag IHE Delft / TU Delft, promotor Prof. dr. S. Uhlenbrook IHE Delft / TU Delft, promotor Dr. Y. Mohamed IHE Delft, copromotor Independent members: Prof.dr. D. P. Solomatine IHE Delft / TU Delft Prof.dr. G.P.W. Jewitt IHE Delft / University of Kwazulu-Natal, South Africa Prof.dr. E. Van Beek University of Twente Prof.dr. S. Hamad NBI, Uganda Prof.dr. M.J. Franca TU Delft,
    [Show full text]
  • The Derg-SPLM/A Cooperation: an Aspect of Ethio-Sudan Proxy Wars
    The Derg-SPLM/A Cooperation: An Aspect of Ethio-Sudan Proxy Wars Regassa Bayissa∗ Abstract The warm and friendly Ethio-Sudan diplomatic relations that followed Sudan’s independence in 1956 and the long standing frontier trade between the two countries have been severely damaged by the outbreak of civil wars in southern Sudan in 1955 as well as in Eritrea in 1962. As the civil wars intensified in both countries, the influx of refugees and insurgents across their common border took place. Internal political and socio-economic problems in Ethiopia and the Sudan, together with super-power rivalries in the Horn brought about periods of increasing hostilities between the two countries. On a tit for tat basis, both the Imperial and military governments of Ethiopia and the successive governments of the Sudan came to encourage and assist cross-border guerrilla forces from either side. Thus, animosity rather than cooperation characterized relations between the Sudan and Ethiopia until the fall of the Derg in 1991. Keywords: Derg, Ethio-sudan relations, SPLM/A, proxy wars Introduction The Upper Nile and Jonglei regions of Southern Sudan bordering Gambella and the Gambella region itself were intensively affected by the wars between the governments of the Sudan and the Anyanya I (the southern Sudan Guerilla group in the first civil war 1955- 1972), the SPLA (Sudan People’s Liberation Army of the second civil war 1983-2005), the Lou-Jikany conflict (1993-1994), the armed conflicts following the splits within the SPLM/A and the South Sudan Independence Movement Army (SSIM/A) 1991-2005). The Sudan governments claimed that Ethiopia was supporting the South Sudan guerrillas struggling to secede from the north while the governments of Ethiopia accused successive Sudanese governments of material and moral support to the Eritrean secessionist movements.
    [Show full text]
  • Local History of Ethiopia : Raayo
    Local History of Ethiopia Raayo - Ryke © Bernhard Lindahl (2005) HFE66 Raayo (Ra'ayo) (mountain) 14°12'/39°00' 2525 m 14/39 [Gz] east of Adwa rab (A) hunger, famine; (Som) 1. narrow place; 2. want, desire JED01 Rab (area & place) c700 m 10/42 [WO Gu] Railway station 25 km inside Ethiopia. raba (O) age grade 24-32 years of the Oromo gada system, regarded as the senior warriors JDJ70 Rabal (area), cf Rabel 09/41 [WO] ?? Rabat ../.. [Yo] In 1982 the TPLF negotiated permission by the Afar to operate a base at Rabat in the isolated Magale area. [Young 1997] rabassa: rabbaas (Som) jump /repeatedly/; rabash (Som) trouble, nuisance JDR10 Rabassa (area) 10/41 [WO] rabbi (O,Som) God HCF65 Rabbi 05°58'/39°48' 1301 m, cf Rebbi .. 05/39 [WO Gz] HEU... Rabea (village) see under Mekele 13/39 [n] HDU54 Rabel 10°27'/39°42' 2390 m, south-east of Were Ilu 10/39 [Gz] HDU63 Rabel (Rabiel) 10°33'/39°36' 2965 m 10/39 [Gz Ad] south-east of Were Ilu (centre in 1964 of Gishe wereda) /this Rabel?:/ The first airdrop of relief food was carried out on 13 February 1985 near Rabel, a village situated on a high plateau about 250 km north-east of Addis Abeba. "RRC agreed to the airdrop and gradually became a strong supporter of the operation which utilised a new airdropping technique developed in the United States. The grain was rebagged into double or triple sacks containing 25 kg each and placed on wooden pallets which were dropped from a height of 6 to 10 metres above the ground.
    [Show full text]
  • Modeling for Inter-Basin Groundwater Transfer Identification Between Middle Abay River Basin and Upper Awash River Basin
    Modeling for Inter-Basin Groundwater Transfer Identification between Middle Abay River Basin and Upper Awash River Basin By: Dure Mulatu Addis Ababa University Addis Ababa, Ethiopia June, 2017 Addis Ababa University Addis Ababa Institute of Technology School of Graduate Studies School of Civil and Environmental Engineering Modeling for Inter-Basin Groundwater Transfer Identification between Middle Abay River Basin and Upper Awash River Basin By: Dure Mulatu A thesis submitted to the School of Graduate Studies of Addis Ababa University in Partial fulfillment of the Degree of Master of Science in Hydraulic Engineering. Advisor: Dr - Ing Mebruk Mohammed June, 2017 Addis Ababa University Addis Ababa Institute of Technology School of Graduate Studies School of Civil and Environmental Engineering Modeling for Inter-Basin Groundwater Transfer Identification between Middle Abay River Basin and Upper Awash River Basin A thesis submitted to the School of Graduate Studies of Addis Ababa University in Partial fulfillment of the Degree of Master of Science in Hydraulic Engineering. By: Dure Mulatu Approval by Board of Examiners Dr. Ing Mebruk Mohammed ------------------------------ Advisor Signature Dr. Agizew Nigussie ------------------------------- Internal Examiner Signature Dr. Belete Birhanu ------------------------------- External Examiner Signature Dedication To my mother Kibe Balcha whom I love very much Abstract Groundwater flow models are important for the identification of inter-basin groundwater transfer between adjacent basins. Numerical groundwater model, TAGSAC has been used to study the inter-basin groundwater transfer (IBGWT) between middle Abay River basin and upper Awash River basin. Three steady state groundwater flow models (for middle Abay River basin, upper Awash River basin and for the two combined basins) were first created and calibrated for the inventoried wells.
    [Show full text]
  • United States Cooperative Progra 1961 Annual Report
    ETOPIA -UNITED STATES COOPERATIVE PROGRA FOR THE STUDY OF WATER RESOURCES In Collaboration With United States ited States Department of State Int'l. Cooperation Admna. Department of the Interior Bureau of ReclamAtion Imperial Ethiopian Government Ministry of Public Works and Communications Water Resources Department 1961 ANNUAL REPORT OF THE BUREAU OF RECLAMATION ON TI[E BLUE NILE RIVER BASIN INVESTIGATIONS Washington, D. C. December 31, 1961 .I. D" Reference Cen'Te- Room 1656 NS UNITED STATES DEPARTMENT OF THE INTERIOR BUREAU OF RECLAMATION WASHINGTON 25, D. C. IN REPLY REFER TO! 220 December 31, 1961 Mr. Allen Loren, Director USAID to Ethiopia c/o American Embassy Addis Ababa, Ethiopia Dear Mr. Loren: Under the terms of the Agreement, dated August 9, 1957, between the Department of the Interior and the Department of State, providing for Water Resources Investigations in the Blue Nile River Basin, Ethiopia, an annual report is required. It is a pleasure to submit herewith the annual report for the calendar year 1961. This is the fourth such report, the project being in the fifth ot six years as now programed. Sincerely yours, o er Co s •w-.VQ ..',t. ~Vy Finchaa Falls One of the more promising future developments is associated with the use of Chomen Swamp, above the falls, for storage, and the irrigation of land in the lower valley, coupled with a power installation below the falls. 1961 ANNUAL REPORT BLUE NILE RIVER BASIN INVESTIGATIONS CONTE NTS Photo of Finchaa Falls Frontispiece I. Introduction....................................... ...I. .. Fig. 1 - Organization for Project Operations 1962 II. Conduct of Operations ...................................
    [Show full text]
  • Ethiopia and the Nile Dilemmas of National and Regional Hydropolitics
    Research Collection Doctoral Thesis Ethiopia and the Nile Dilemmas of national and regional hydropolitics Author(s): Arsano, Yacob Publication Date: 2007 Permanent Link: https://doi.org/10.3929/ethz-a-005380361 Rights / License: In Copyright - Non-Commercial Use Permitted This page was generated automatically upon download from the ETH Zurich Research Collection. For more information please consult the Terms of use. ETH Library Yacob Arsano Ethiopia and the Nile Dilemmas of National and Regional Hydropolitics © 2007, ETH Zurich and Yacob Arsano Center for Security Studies, Swiss Federal Institute of Technology, Zurich ETH Zentrum SEI, Seilergraben 49, CH-8092-Zurich, Switzerland. Tel. ++41 (0)44 632 40 25 Fax ++41 (0)44 632 19 41 www.css.ethz.ch Author contact Yacob Arsano, Addis Ababa University, Department of Political Sciences and International Relations, Email: [email protected] Fulltext online available at www.isn.ethz.ch All rights reserved. No part of this publication may be used or reproduced in any manner whatsoever without the prior written permission of the author except in the case of brief quotations embodied in critical articles and reviews. Cover-Photo Tis Isat Falls / Blue Nile Falls by Torleif Svensson Layout and graphics Fabian Furter Fonts Adobe Caslon Pro News Gothic Std. (Cover) ISBN 3-905696-14-2 Ethiopia and the Nile Dilemmas of National and Regional Hydropolitics Thesis presented to the Faculty of Arts of the University of Zurich for the degree of Doctor of Philosophy by Yacob Arsano of Ethiopia Accepted in the summer semester on the recommendation of Prof. Dr. Andreas Wenger and Prof.
    [Show full text]
  • Ethiopian Environment and Forest Research Institute
    የኢትዮጵያ የአካባቢና የደን ምርምር ኢንስቲትዩት ETHIOPIAN ENVIRONMNET AND FOREST RESEARCH INSTITUTE Forest and Environment Research: Technologies and Information Edited by: Mehari Alebachew Getachew Desalegn Wubalem Tadesse Agena Anjulo Fassil Kebede i ETHIOPIAN ENVIRONMENT AND FOREST RESEARCH INSTITUTE Forest and Environment Research: Technologies and Information Edited by: Mehari Alebachew Getachew Desalegn Wubalem Tadesse Agena Anjulo Fasil Kebede PROCEEDINGS OF THE 1ST TECHNOLOGY DESSIMINATION WORKSHOP 26th - 27th November 2015 Tokuma Hotel, Adama, Ethiopia ii Table of contents WELCOME SPEECH ..................................................................................................................................... viii OPENING SPEECH .......................................................................................................................................... x PLANTATION AND AGROFORESTRY ............................................................................................................... 1 EARLY GROWTH PERFORMANCE OF JUNIPERUS PROCERA HOCHST. EX ENDL IN DEGRADED LANDS OF NORTH SHOA ................................................................................................................................................ 1 COMMUNITY ESTABLISHED EUCALYPT PLANTATIONS IN ETHIOPIA FOR DEGRADED LAND RESTORATION AND INCOME GENERATION ........................................................................................................................... 7 CHARACTERIZATION OF TRADITIONAL AGROFORESTRY PRACTICES AND SOCIOECONOMIC
    [Show full text]
  • The Climate and Hydrology of the Upper Blue Nile River
    The GeographicalJournal,Vol. 166, No. 1, March 2000, pp. 49-62 The Climate and Hydrology of the Upper Blue Nile River DECLAN CONWAY School of Development Studies, University of East Anglia, Norwich NR4 7U E-mail: [email protected] This paper was accepted for publication in March 1999 The Upper Blue Nile river basin is the largest in Ethiopia in terms of volume of dis- charge, second largest in terms of area, and contributes over 50 per cent of the long- term river flow of the Main Nile. This paper provides a review of the nature and variability of the climate and hydrology in the source region of the Blue Nile - the cen- tral Ethiopian Highlands. Annual rainfall over the basin decreases from the south-west (>2000 mm) to the north-east (around 1000 mm), with about 70 per cent occurring between June and September. A basin-wide time series of annual rainfall constructed from 11 gauges for the period 1900 to 1998 has a mean of 142lmillimetres, minimum in 1913 (1 148 mm) and maximum in 1903 (1757 mm). Rainfall over the basin showed a marked decrease between the mid-1 960s and the late 1980s and dry years show a degree of association with low values of the Southern Oscillation Index (Sol).The October to February dry season in 1997198 was the wettest on record and responsible for widespread flooding across Ethiopia and also parts of Somalia and Kenya. Available river flow records, which are sparse and of limited duration, are presented for the Blue Nile and its tributaries upstream of the border with Sudan.
    [Show full text]
  • Local History of Ethiopia Ama - Amzanaghir © Bernhard Lindahl (2005)
    Local History of Ethiopia Ama - Amzanaghir © Bernhard Lindahl (2005) ama, hamaa (O) honeybadger, Egyptian mongoose, Herpestes ichneumon HDM13 Ama 09°11'/39°39' 1627 m 09/39 [Gz] JDH46 Ama Yusefo 09°28'/41°18' 1587 m 09/41 [Gz] HDU52c Amad Washo (recorded in 1841) 10/39 [Ha] HEC38 Amadamit, see Amedamit amado: amedu (amädu) (A) the ashes; amed washa, ash cave; ado amo (Afar) white head JEA77 Amado (area) 11/40 [WO 20] Site in the upper Mille valley south of the volcano Gura Ale and only about a couple of square kilometres in size. In October 1973 the International Afar Research Expedition with 18 people in four LandRovers visited Amado. "Amado is noteworthy for its thick, fluviatile, crystalline tuffs containing beautiful translucent fossil wood and hundreds of monkey and baboon fossils. Coppens and Guérin judged the elephants and rhinos to be between 3 and 4 million years old. Some of the associated sediments looked like hot spring deposits, and the fossil wood looked like palm." The expedition in five days collected nearly 400 fossils, a quarter of them being monkeys. [J Kalb 2001 p 100] JEC01 Amadu (Lo Ammadu, Amadoo) (plain) 10/41 [Gu WO Ha] HCJ80 Amaia (Ammaia), see Ameya HCS44 Amairaba 07°39'/37°54' 2460 m 07/37 [WO Gz] amaja: ameja, amija (A) kind of shrub or small tree, Hypericum revolutum, H. quartinianum JDJ12 Amaja (Amagia) (saddle), see under Grawa 09/41 [+ Gu] cf Ameja, Amija ?? Amajah ../.. [Pa] A Muslim settlement in eastern Shewa, near the Kessem river, "the population of which /in the 1530s/ welcomed Grañ's forces, and prayed for the latter's victory".
    [Show full text]