Advertisement

Regional Environmental Change

, Volume 14, Issue 1, pp 321–331 | Cite as

The long-term hydrology of East Africa’s water tower: statistical change detection in the watersheds of the Abbay Basin

  • Solomon Gebreyohannis GebrehiwotEmail author
  • Annemieke I. Gärdenäs
  • Woldeamlak Bewket
  • Jan Seibert
  • Ulrik Ilstedt
  • Kevin Bishop
Original Article

Abstract

Forty-five years (1960–2004) of hydrological data from 12 watersheds in the Abbay Basin, Ethiopia, were tested for possible trends over the entire time series and differences in medians (step-wise changes) between three sub-periods. The classification of the sub-periods was based on the major political changes in 1975 and 1991. Variables investigated were rainfall (P), total flow (Q t), high flow (Q h), low flow (Q l), low flow index (LFI) and run-off coefficient (C). Data were checked for outliers, errors and homogeneity. Trend was tested after serial and cross-correlation tests. The data for each variable were serially uncorrelated from 1 to 10 lag years. There were five globally significant trends out of 50 test cases and 36 significant step-wise changes out of 180 tests. The majority of the significant changes were watershed specific. Run-off coefficient was the single variable showing a consistently increasing trend and stood for ca. 25 % of the total significant trends and step-wise changes. Half of these changes occurred after 1991. We concluded that despite the land use policy changes in 1975 and 1991, as well as the long-term soil degradation, the hydrological regime was quite stable over the 45-year period, with the exception of an increase in the run-off coefficient in the latter part of the run-off record in some watersheds.

Keywords

Blue Nile Ethiopia Run-off coefficient Step-wise change Trend Watershed 

Notes

Acknowledgments

This research was supported by funds from SIDA (Swedish International Development Agency) and The Swedish Foreign Affairs Office project “Soil and water management in agricultural production”.

References

  1. Alexandersson H (1986) A homogeneity test applied to precipitation data. J Climatol 6(6):661–675CrossRefGoogle Scholar
  2. Baldassarre GD, Elshamy M, van Griensven A, Soliman E, Kigobe M, Ndomba P, Mutemi J, Mutua F, Moges S, Xuan Y, Solomatine D, Uhlenbrook S (2011) Future hydrology and climate in the River Nile basin: a review. Hydrol Sci J 56(2):199–211CrossRefGoogle Scholar
  3. Bates BC, Kundzewicz ZW, Wu S, Palutikof JP (eds) (2008) Climate change and water. Technical Paper of the Intergovernmental Panel on Climate Change. IPCC Secretariat, Geneva, p 210Google Scholar
  4. Bayabil HK, Tilahun SA, Collick AS, Yitaferu B, Steenhuis TS (2010) Are runoff processes ecologically or topographically driven in the (sub) humid Ethiopian highlands? The case of the Maybar watershed. Ecohydrology 3:457–466CrossRefGoogle Scholar
  5. Bekele M (2003) Forest property rights, the role of the state, and institutional exigency: the Ethiopian Experience. PhD Thesis, Swedish University of Agricultural Sciences, Uppsala, SwedenGoogle Scholar
  6. Bewket W (2007) Rainwater harvesting in drought-prone areas of the Ethiopian highlands. East Afr Soc Sci Res Rev 23(3):1–26Google Scholar
  7. Bewket W (2011) Farmers’ knowledge of soil erosion and control measures in the Northwestern highlands of Ethiopia. Afr Geograph Rev 30(2):53–70CrossRefGoogle Scholar
  8. Bewket W, Conway D (2007) A note on the temporal and spatial variability of rainfall in the drought-prone Amhara region of Ethiopia. Int J Climatol 27:1467–1477CrossRefGoogle Scholar
  9. Blöschl G, Ardoin-Bardin S, Bonne M, Dorninger M, Goodrich D, Gutknecht D, Matamoros D, Merz B, Shand P, Szolgay J (2007) At what scales do climate variability and land cover change impact on flooding and low flows? Hydrol Process 21:1241–1247CrossRefGoogle Scholar
  10. Bruijnzeel LA (2004) Hydrological functions of tropical forests: not seeing the soil for the trees? Agric Ecosyst Environ 104:185–228CrossRefGoogle Scholar
  11. Burn DH, Hag Elnur MA (2002) Detection of hydrologic trends and variability. J Hydrol 255:107–122CrossRefGoogle Scholar
  12. Burn DH, Abdul Aziz OI, Pietroniro A (2004a) A comparison of trends in hydrological variables for two watersheds in the Mackenzie River Basin. Can Water Resour J 29(4):283–298CrossRefGoogle Scholar
  13. Burn DH, Cunderlik JM, Pietroniro A (2004b) Hydrological trends and variability in the Liard River basin. Hydrol Sci J 49(1):53–67CrossRefGoogle Scholar
  14. Calder IR (2005) Blue Revolution: Integrated Land and Water Resource Management, 2nd edn. Earthscan, LondonGoogle Scholar
  15. Conway D (2000) The climate and hydrology of the upper Blue Nile river. Geograph J 166(1):49–62CrossRefGoogle Scholar
  16. Dahmen ER, Hall MJ (1990) Screening of hydrological data: tests of stationarity and relative consistency. International Institute for Land and Improvement (ILRI), Wageningen, The NetherlandsGoogle Scholar
  17. ECSNCC (Ethiopian Civil Society Network on Climate Change) (2001) A review and analysis of land administration & use legislation and application. Federal Democratic Republic of Ethiopia and Regional States of Amhara, Oromia, SNNP and Tigray. Addis Ababa, EthiopiaGoogle Scholar
  18. Eriksson L, Johansson E, Kettaneh-Wold N, Wold S (2001) Multi- and Megavariate Data Analysis: Principles and Applications. UMETRICS AB, UmeåGoogle Scholar
  19. FAO (2000) Water and Agriculture in the Nile Basin, Nile Basin Report to ICCON, AGL/MISC/29/2000. Land Water Development Division, FAO, Rome, ItalyGoogle Scholar
  20. Fasil GK (1991) Economic consequences of drought, crop failure and famine in Ethiopia, 1973–1986. AMBIO 20(5):183–185Google Scholar
  21. Gebrehiwot SG (2012) Hydrology and Forests in the Abbay Basin: What can be learned from half a century of observations and community perception for water management? PhD Thesis, Swedish University of Agricultural Sciences, Uppsala, SwedenGoogle Scholar
  22. Gebrehiwot SG, Ayele T, Bishop K (2010) Forest cover and stream flow in a headwater of the Abbay: complementing observational data analysis with community perception. AMBIO 39:284–294CrossRefGoogle Scholar
  23. Gebrehiwot SG, Ilstedt U, Gärdenas AI, Bishop K (2011) Hydrological characterization of watersheds in the Abbay Basin, Ethiopia. Hydrol Earth Syst Sci 15:11–20CrossRefGoogle Scholar
  24. Gebremedhin B, Pender J, Tesfaye G (2006) Community natural resource management in the highlands of Ethiopia. Strategies for sustainable land management in the East African highlands. In: Pender J, Place F, Ehui S (eds) International Food Policy Research Institute, WashingtonGoogle Scholar
  25. Gebremedhin B, Hoekstra D, Jemaneh S (2007) Heading towards commercialization? The case of live animal marketing in Ethiopia. Improving Productivity and Market Success (IPMS) of Ethiopian Farmers Project Working Paper 5, ILRI (International Livestock Research Institute), Nairobi, Kenya, p 73Google Scholar
  26. Haile AT, Reintjes THM, Habib E, Jetten V, Gebremichael M (2011) Rain event properties at the source of the Blue Nile River. Hydrol Earth Syst Sci 15:1023–1034CrossRefGoogle Scholar
  27. Hamed KH (2008) Trend detection in hydrologic data: the Mann–Kendall trend test under the scaling hypothesis. J Hydrol 349:350–363CrossRefGoogle Scholar
  28. Hurni H (1988) Degradation and conservation of the resources in the Ethiopian Highlands. Mt Res Dev 8(2/3):123–130Google Scholar
  29. Hurni H, Kebede T, Zeleke G (2005) The implications of changes in population, land use, and land management for surface runoff in the upper Nile Basin area of Ethiopia. Mt Res Dev 25(2):147–154CrossRefGoogle Scholar
  30. Johnson R (1998) The forest cycle and low river flows: a review of UK and international studies. For Ecol Manag 109:1–7CrossRefGoogle Scholar
  31. Liu BM, Collick AS, Zeleke G, Adgo E, Easton ZM, Steenhuis TS (2008) Rainfall-discharge relationships for a monsoonal climate in the Ethiopian highlands. Hydrol Process 22:1059–1067CrossRefGoogle Scholar
  32. Ministry of Water Resources (1998) Abbay River Basin Integrated Development Master Plan Project: Data Collection – Site Investigation Survey and Analysis, Phase 2. BECOM in collaboration with BRGM and ISL Consulting Engineers, Ministry of Water Resources, Ethiopia, Addis Ababa, EthiopiaGoogle Scholar
  33. Ministry of Water Resources (1999) Abbay River Basin Integrated Development Master Plan Project: Data Collection - Site Investigation Survey and Analysis. BECOM in collaboration with BRGM and ISL Consulting Engineers, Ministry of Water Resources, Ethiopia, Addis Ababa, EthiopiaGoogle Scholar
  34. Mohamed YA, van den Hurk BJJM, Savenije HHG, Bastiaanssen WGM (2005) Hydroclimatology of the Nile: results from a regional climate model. Hydrol Earth Syst Sci 9:263–278CrossRefGoogle Scholar
  35. Nega B, Adenew B, GebreSellasie S (2003) Current land policy in Ethiopia. Land Reform: land settlement and cooperatives, special edition. FAO, Rural Development Division, Rome, ItalyGoogle Scholar
  36. Palamuleni LG, Ndomba PM, Annegarn HJ (2011) Evaluating land cover change and its impacts on hydrological regime in Upper Shire river catchment Malawi. Reg Environ Change 11(4):845–855CrossRefGoogle Scholar
  37. Pettitt AN (1979) A non-parametric approach to the change-point problem. Appl Stat 28(2):126–135CrossRefGoogle Scholar
  38. Population Census Commission (2008) Summary and statistics report of the 2007 population and housing census. United Nations Population Fund (UNFPA), Addis Ababa, EthiopiaGoogle Scholar
  39. Rahmato D (2009) The Peasant and the State: Studies in Agrarian Change in Ethiopia 1950s–2000s. Addis Ababa University Press, Addis AbabaGoogle Scholar
  40. SAS Institute Inc (2007) JMP ® 7.0.1. SAS Campus Drive, Cary, North CarolinaGoogle Scholar
  41. Senay G, Asante K, Artan G (2009) Water balance dynamics in the Nile Basin. Hydrol Process 23:3675–3681Google Scholar
  42. Sutcliffe JV, Parks YP (1999) The hydrology of the Nile. IAHS Special Publication no. 5, IAHS Press, Institute of Hydrology, OxfordGoogle Scholar
  43. UMETRICS AB (2009) SIMCA P+ ®, Version 12.0.1.0. Kinnelon NJ, USAGoogle Scholar
  44. UNEP (2010) Africa Water Atlas. Division of Early Warning and Assessment (DEWA), United Nations Environment Programme (UNEP), Nairobi, KenyaGoogle Scholar
  45. Westerberg IK, Guerrero JL, Younger PM, Beven KJ, Seibert J, Halldin S, Freer JE, Xu C-Y (2010) Calibration of hydrological models using flow-duration curves. Hydrol Earth Syst Sci Discuss 7:9467–9522CrossRefGoogle Scholar
  46. World Bank (2006) Ethiopia: Managing water resources to maximize sustainable growth: A World Bank water resources assistance strategy for Ethiopia. World Bank, Washington, DCGoogle Scholar
  47. Yue S, Pilon P, Phinney B, Cavadias G (2002) The influence of autocorrelation on the ability to detect trend in hydrological series. Hydrol Process 16:1807–1829CrossRefGoogle Scholar
  48. Zar JH (1999) Biostatistical Analysis, 4th edn. Prentice Hall, New JerseyGoogle Scholar
  49. Zeleke G, Hurni H (2001) Implications of land use and land cover dynamics for mountain resource degradation in the Northwestern Ethiopian highlands. Mt Res Dev 21(2):184–191CrossRefGoogle Scholar

Web

  1. Bearing Climate, National Oceanic and Atmospheric Administration http://www.beringclimate.noaa.gov/regimes; 23/04/2009
  2. Ministry of Water and Energy, Ethiopia http://www.mowr.gov.et, 05/02/2013

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Solomon Gebreyohannis Gebrehiwot
    • 1
    • 2
    • 7
    Email author
  • Annemieke I. Gärdenäs
    • 3
  • Woldeamlak Bewket
    • 2
  • Jan Seibert
    • 4
    • 5
  • Ulrik Ilstedt
    • 6
  • Kevin Bishop
    • 1
    • 5
  1. 1.Department of Aquatic Sciences and AssessmentSwedish University of Agricultural SciencesUppsalaSweden
  2. 2.Department of Geography and Environmental StudiesAddis Ababa UniversityAddis AbabaEthiopia
  3. 3.Department of Soil and EnvironmentSwedish University of Agricultural SciencesUppsalaSweden
  4. 4.Department of GeographyUniversity of ZurichZurichSwitzerland
  5. 5.Department of Earth SciencesUppsala UniversityUppsalaSweden
  6. 6.Department of Forest Ecology and ManagementSwedish University of Agricultural SciencesUmeåSweden
  7. 7.Ethiopian Institute of Water ResourcesAddis Ababa UniversityAddis AbabaEthiopia

Personalised recommendations