Environmental Management

, Volume 61, Issue 5, pp 860–874 | Cite as

Impact of Soil and Water Conservation Interventions on Watershed Runoff Response in a Tropical Humid Highland of Ethiopia

  • Dagnenet Sultan
  • Atsushi Tsunekawa
  • Nigussie Haregeweyn
  • Enyew Adgo
  • Mitsuru Tsubo
  • Derege Tsegaye Meshesha
  • Tsugiyuki Masunaga
  • Dagnachew Aklog
  • Ayele Almaw Fenta
  • Kindiye Ebabu
Article
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Abstract

Various soil and water conservation measures (SWC) have been widely implemented to reduce surface runoff in degraded and drought-prone watersheds. But little quantitative study has been done on to what extent such measures can reduce watershed-scale runoff, particularly from typical humid tropical highlands of Ethiopia. The overall goal of this study is to analyze the impact of SWC interventions on the runoff response by integrating field measurement with a hydrological CN model which gives a quantitative analysis future thought. Firstly, a paired-watershed approach was employed to quantify the relative difference in runoff response for the Kasiry (treated) and Akusty (untreated) watersheds. Secondly, a calibrated curve number hydrological modeling was applied to investigate the effect of various SWC management scenarios for the Kasiry watershed alone. The paired-watershed approach showed a distinct runoff response between the two watersheds however the effect of SWC measures was not clearly discerned being masked by other factors. On the other hand, the model predicts that, under the current SWC coverage at Kasiry, the seasonal runoff yield is being reduced by 5.2%. However, runoff yields from Kasiry watershed could be decreased by as much as 34% if soil bunds were installed on cultivated land and trenches were installed on grazing and plantation lands. In contrast, implementation of SWC measures on bush land and natural forest would have little effect on reducing runoff. The results on the magnitude of runoff reduction under optimal combinations of SWC measures and land use will support decision-makers in selection and promotion of valid management practices that are suited to particular biophysical niches in the tropical humid highlands of Ethiopia.

Keywords

Paired watershed Runoff reduction Curve Number Drought-prone Ethiopia 
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Notes

Acknowledgements

The authors are grateful to Anteneh Wubet and Getachew Dagnew for their field assistance during primary data collection from Kasiry and Akusity watersheds. We are also thankful to the International Platform for Dryland Research and Education (IPDRE) of Tottori University for offering an overseas travel grant, and to the Arid Land Research Center for providing an appropriate research environment to the principal author. This work was supported by JSPS KAKENHI Grant Number JP25257417. The manuscript benefited from the comments of anonymous reviewers.

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Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

267_2018_1005_MOESM1_ESM.docx (1.3 mb)
Supplementary Information

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Dagnenet Sultan
    • 1
    • 2
  • Atsushi Tsunekawa
    • 3
  • Nigussie Haregeweyn
    • 4
  • Enyew Adgo
    • 5
  • Mitsuru Tsubo
    • 6
  • Derege Tsegaye Meshesha
    • 5
  • Tsugiyuki Masunaga
    • 7
  • Dagnachew Aklog
    • 8
  • Ayele Almaw Fenta
    • 1
  • Kindiye Ebabu
    • 1
    • 5
  1. 1.The United Graduate School of Agricultural SciencesTottori UniversityTottoriJapan
  2. 2.School of Civil and Water Resource Engineering, Institute of TechnologyBahir Dar UniversityBahir DarEthiopia
  3. 3.Arid Land Research CenterTottori UniversityTottoriJapan
  4. 4.International Platform for Dryland Research and EducationTottori UniversityTottoriJapan
  5. 5.Department of Natural Resources ManagementBahir Dar UniversityBahir DarEthiopia
  6. 6.Institute for Soil, Climate and WaterAgricultural Research CouncilPretoriaSouth Africa
  7. 7.Faculty of Life and Environmental ScienceShimane UniversityMatsueJapan
  8. 8.Center for International AffairsTottori UniversityTottoriJapan

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