Semi-circle bunds
Type: Technologies
Creation: 2012-01-09 10:40 Updated: 2019-08-02 16:26
Compilers: kasem al ahmad
Reviewers: Fabian Ottiger, Alexandra Gavilano
Country/ region/ locations where the Technology has been applied and which are covered by this assessment
- Country: Syrian Arab Republic
- Region/ State/ Province: Aleppo, Idleb
- Further specification of location (e.g. municipality, town, etc.), if relevant: Afrin (Maghara and Khaltan village) And Harem (Betya village)
- Map: View Map
Description of the SLM Technology
Short description of the Technology
Semi-circle stone bunds are used as soil conservation and water harvesting structures to reduce soil erosion and improve productivity of olive trees.
Detailed description of the Technology
Semi-circle stone bunds are used as soil and water harvesting structures to improve productivity of trees, especially olive trees, on steep slopes. These are small-scale stone structures, with diameters between 3-5 m, established to catch rainfall and runoff from small micro-catchments covering relatively short slopes. This type of freestanding system (not contour system) is suitable for fields where trees are distributed in a staggered array. The slope steepness ranges from 15-40 degrees. Stones are mined from wasteland and transported to the slopes using tractors. Then the stones are set out in a semi circle (crescent) manually from a down side of the tree. The stone bunds are about 40 cm high with a base width of 30-40 cm. Most of the farmers add soil around the tree trunk and some of them add manure to improve the soil fertility. The technology makes the mechanized tillage difficult because of the layout of the structures. This reduces number of tillage operations and hence reduces erosion since tillage is one of the main causes of soil erosion under these conditions. The structures also reduce runoff velocity, which increases water availability for the plant roots (water harvesting) and also allows for more sedimentation around the trees and less transportation of soil particles and nutrients outside the field (soil conservation).
Purpose of the Technology: Semi-circle stone bunds are used to reduce losses of soil and nutrients and capture runoff water which helps to rehabilitate degraded land and improves the yield.
Establishment / maintenance activities and inputs: For one hectare of land with 100 bunds approximately 50 persons are needed to establish the bunds. The stones are set out in a semi-circle manually. A shovel is needed to prepare and level the stones bed. The costs are about $1950, which includes the price of the stones, transportation, equipment and labours. Then the bunds need maintenance every year, this will cost $54 per hectare. The perennial olive trees are mainly planted in January.
Natural / human environment: The area is dominated by steep slopes in a mountainous area in the north west of Syria. Small holdings are typical for this area with small plot sizes, narrow fields and shallow soil. Annual rainfall is between 400-600 mm. The technology was introduced to the community few years ago. Farmers were trained on how to layout, implement and maintain the structures by ICARDA and local extension services. Individual farmers are applying the technology on their own fields.
Photos of the Technology
- 📍 Afrin, Maghara village, Aleppo
- 📷 ICARDA (P.O. Box 5466, Aleppo, Syria)
- 📍 Edlib, Bitya village, Edlib
- 📷 ICARDA (P.O. Box 5466, Aleppo, Syria)