WELCOME Identifying suitable areas for water harvesting  in the Upper Blue Nile Basin, Ethiopa Authors:  Yihun Dile Taddel...
What are they? Pitting Strip catchment tillage Meskat-type system Contour bunds Semi-circular bunds Floodwater harvesting ...
 
Why Water Harvesting Dry spells Flooding Drought Land degradiation
Then what? <ul><li>Bridging dry spells and droughts, and creats a resilient farming system which </li></ul><ul><li>can pro...
BUT?
 
Precipitation DEM Land Cover Soil Surface  Analysis Slope map Land cover rastar map Land cover rastar map Vector to grid c...
 
Suitability Criteria   Suitability values  1  2  3  4  5   Precipitation(mm)  <200  >1200  200-400  800-1200  400-800 Slop...
Percent Influence Assignment Percent Influence Parameter  Precipitation Slope Land use Soil Condition - 1  25 25 25 25 Con...
Equal inflience assignment for  precipitation, slope, land use and soil 30% influence assignment for  Precipitation & slop...
35%, 25%, 20% and 20% influence assignment For precipitation, slope, land use & soil resp. 25%, 35%, 20% and 20% influence...
Results % precipitation slope 0 1 0 1 0 1 29 23 28 23 16 2 61 62 61 61 57 3 6 10 8 11 23 4 0 0 0 0 0 5 Condition-5 Conditi...
Discussion and conclusion <ul><li>The Upper Blue Nile has a large potential for water harvesting: 6% to 24%, </li></ul><ul...
Thank You Questions?
Upcoming SlideShare
Loading in …5
×

Identifying suitable areas for water harvesting in the upper Blue Nile basin, Ethiopia - Yihun Dile, Stockholm Environment Institute, Ethiopia

1,083 views
918 views

Published on

Published in: Travel
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
1,083
On SlideShare
0
From Embeds
0
Number of Embeds
35
Actions
Shares
0
Downloads
18
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide
  • Problems in the Upper Blue Nile: variability of rainfall; droughts; dry spells; flooding
  • Identifying suitable areas for water harvesting in the upper Blue Nile basin, Ethiopia - Yihun Dile, Stockholm Environment Institute, Ethiopia

    1. 1. WELCOME Identifying suitable areas for water harvesting in the Upper Blue Nile Basin, Ethiopa Authors: Yihun Dile Taddele , Louise Karlberg, Johan Rockström Stockholm Environment Institute
    2. 2. What are they? Pitting Strip catchment tillage Meskat-type system Contour bunds Semi-circular bunds Floodwater harvesting within the stream bed Ephemeral Stream Diversion Hillside sheet/rill runoff utilization
    3. 4. Why Water Harvesting Dry spells Flooding Drought Land degradiation
    4. 5. Then what? <ul><li>Bridging dry spells and droughts, and creats a resilient farming system which </li></ul><ul><li>can produce more crop per drop </li></ul><ul><li>Avoid flooding problems by flattening the hydrograph: Ex-situ water harvesting </li></ul><ul><li>Supports a sustained stream flow downstream: both in-situ and ex-situ </li></ul><ul><li>Improves soil fertility </li></ul><ul><li>with water harvesting </li></ul><ul><li>- without water harvesting </li></ul>
    5. 6. BUT?
    6. 8. Precipitation DEM Land Cover Soil Surface Analysis Slope map Land cover rastar map Land cover rastar map Vector to grid conversion Reclassified Precipitation Reclassified slop map Reclassified land cover Reclassified Soil Reclassifying into 5 classes WH suitability maps Weighted Overlay Analysis
    7. 10. Suitability Criteria Suitability values 1 2 3 4 5 Precipitation(mm) <200 >1200 200-400 800-1200 400-800 Slope(%) >20 12-20 8-12 2-8 <2 Land cover Bushland, forest N.A N.A plantations cultivated land woodland, grassland irrigated land swamp, shurbland Soil Leptosols Arenosols Vertisols Luvisols, Cambisols Regosols Acrisols, Alisols Fluvisols, Nitisols
    8. 11. Percent Influence Assignment Percent Influence Parameter Precipitation Slope Land use Soil Condition - 1 25 25 25 25 Condition - 2 30 30 20 20 Condition - 3 35 25 20 20 Condition - 4 25 35 20 20 Condition - 5 35 30 20 15 S = ∑w i *x i S = final suitability score; w i is weight of factor i and x i is the criterion score of factor i Suitability Analysis
    9. 12. Equal inflience assignment for precipitation, slope, land use and soil 30% influence assignment for Precipitation & slope, and 20% for land use & soil Results
    10. 13. 35%, 25%, 20% and 20% influence assignment For precipitation, slope, land use & soil resp. 25%, 35%, 20% and 20% influence assignment For precipitation, slope, land use & soil resp. Results
    11. 14. Results % precipitation slope 0 1 0 1 0 1 29 23 28 23 16 2 61 62 61 61 57 3 6 10 8 11 23 4 0 0 0 0 0 5 Condition-5 Condition-4 Condition-3 Condition-2 Condition-1 Suitability level
    12. 15. Discussion and conclusion <ul><li>The Upper Blue Nile has a large potential for water harvesting: 6% to 24%, </li></ul><ul><li>most suitable and over 50% moderate suitability </li></ul><ul><li>The results of the study are highly sensitive to precipitation amounts </li></ul><ul><li>If higher value is given for other land use types such as open woodland, the </li></ul><ul><li>potential suitable area will increase considerably </li></ul><ul><ul><li>soil type: Luvisols, Cambisols, Vertisols </li></ul></ul><ul><ul><li>increases water avilability for livestock – increases farmers tendency to </li></ul></ul><ul><ul><li>invest in agriculture – which has nexus effect on increasing on </li></ul></ul><ul><ul><li>water productiity </li></ul></ul>
    13. 16. Thank You Questions?

    ×