Improving runoff estimation in a monsoon climatic region of Ethiopia

2016 Fiscal Year Research-status Report

• Project/Area Number: 16K01218
• Research Institution: Tottori University
• Principal Investigator: Haregeweyn N 鳥取大学, 国際乾燥地研究教育機構, 特命准教授 (30754692)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: rainfall / land use type / soil depth / soil moisture / runoff mechanisms

Outline of Annual Research Achievements

Soil moisture in crop and grazing land use types was monitored using EC5 soil moisture at five different soil depths and data were recorded using EM50 data loggers.
In cropland, higher soil moisture amount varying across soil depth was observed at the beginning of August (ranging from 0.15% at 120cm to 0.33% at 20cm) and the variation continued until the third week of November (range = 0.16-0.25%).
In grazing land, higher soil moisture content was observed at the beginning of August ranging between 0.11% -0.59%, where the highest content 0.59 % was observed at a depth 102cm and the lowest value of 0.11 at a depth 10 cm. This showed a decreasing trend until the end of the monitoring period, which correspond to 0.02 and 0.52 % for 102 cm and 10 cm, respectively.

Current Status of Research Progress

3: Progress in research has been slightly delayed.

Reason

it started slightly delayed for the following reasons:
importing of moisture sensors was delayed due to lengthy custom process in Ethiopia and site selection and agreement with data attendants.

Strategy for Future Research Activity

Continue rainfall-soil moisture- runoff data monitoring and collection in the current and two additional watersheds;
Generate long-term land use conversion maps to see their socioeconomic consequences and effects in runoff response and
Data organization and compilation.

Causes of Carryover

the research activity started late than initially planned as more time was need to import research equipment to Ethiopia, site slection and agree with land owners.

Expenditure Plan for Carryover Budget

We will carryout soil moisture data monitoring in two additional sites. So we will have in total three study sites.
We will also map land use change and see the effect on the hydrology and socio-economics.

Research Products

• [Journal Article] Comprehensive assessment of soil erosion risk for better land use planning in river basins: Case study of the Upper Blue Nile River (2017)
  • Author(s): Haregeweyn, N., Tsunekawa, A., Poesen, J., Tsubo, M., Meshesha, DT., Fenta, AA., Nyssen, J., Adgo, E.
  • Journal Title: Science of the Total Environment Volume: 574 Pages: ９５～１０８
  • DOI: http://dx.doi.org/10.1016/j.scitotenv.2016.09.019
  • Peer Reviewed / Open Access / Int'l Joint Research