Large semi circular stone bunds on hillside (Eyasu Yazew (Mekelle University, P.O.Box 231, Mekelle, Ethiopia))
Large semi circular stone bunds are constructed by excavating a foundation of 0.1 - 0.2 m following the semi circle and building of the embankment using stones with a decreasing height at the tips to evacuate excess runoff. 1 - 3 pits are excavated within the semi circle for for planting trees.
Large semi circular stone bunds (Large half moons) are constructed with a diameter of 6 m and corresponding perimeter/length of 9.42 m. The spacing between the tips of adjacent bunds within a row and between the base bund and tip of adjacent rows is 3 m. The height of the embankment varies from 0.5 - 0.75 m at the base bund to 0.4 - 0.5 m at the tip while the corresponding width varies from 0.4 - 0.5 m to 0.2 - 0.3 m. The planting pit has a diameter and depth of 0.3 m.
Purpose of the Technology: Large semi circular stone bunds assist in decreasing slope length, runoff velocity and soil loss; and improving runoff harvesting, soil moisture and groundwater recharge.
Establishment / maintenance activities and inputs: The establishment of large semi circular stone bunds involves collection of stones, alignment of a contour and the semi circle, excavation of foundation, construction of the embankment and digging of planting pits and runoff harvesting ditch. The maintenance includes re-enforcing the embankment and dredging sediment from runoff harvesting ditch during the dry season.
Natural / human environment: Large semi circular stone bunds are implemented in foot (5 - 8%) and hill (8 - 16%) slopes and in medium and light soil types of shallow to moderate depth (0.2 - 0.8 m). It reduces runoff amount and velocity thereby decreasing soil loss and desertification/land degradation. It also improves soil moisture availability and groundwater recharge.
It is mostly constructed using communal labour and there is a moderate trend of spontaneous adoption. The technology is witnessed to be increasing fruit and fodder production thereby improving the livelihood of the land users. It, however, demands high labour especially during establishment.
Location: Kilte Awlaelo, Tigray, Ethiopia
No. of Technology sites analysed:
Spread of the Technology: evenly spread over an area (approx. 10-100 km2)
In a permanently protected area?:
Date of implementation: less than 10 years ago (recently)
Type of introduction
| Specify input | Unit | Quantity | Costs per Unit (Birr) | Total costs per input (Birr) | % of costs borne by land users |
| Labour | |||||
| Labour | ha | 1.0 | 3667.0 | 3667.0 | 60.0 |
| Equipment | |||||
| Tools | ha | 1.0 | 75.0 | 75.0 | |
| Total costs for establishment of the Technology | 3'742.0 | ||||
| Total costs for establishment of the Technology in USD | 207.89 | ||||
| Specify input | Unit | Quantity | Costs per Unit (Birr) | Total costs per input (Birr) | % of costs borne by land users |
| Labour | |||||
| Labour | ha | 1.0 | 117.0 | 117.0 | 100.0 |
| Total costs for maintenance of the Technology | 117.0 | ||||
| Total costs for maintenance of the Technology in USD | 6.5 | ||||
Increased investment in health care as a result of increased income.
