Jessour is the plural of a Jessr which is the hydraulic unit comprising a dyke, spillway, terrace (cropping area: fruit trees and annuals), and impluvium (runoff catchment area) (van Delden H.)
Jessour technology is generally practised in mountain dry regions (less than 200 mm annually) with medium to high slopes. This technology was behind the installation of very old olive orchards based on rainfed agriculture in rugged landscapes which allowed the local population not only to ensure self-sufficiency but also to provide neighbouring areas many agricultural produces (olive oil, dried figs, palm dates, etc.).
Jessour is the plural of jessr, which is a hydraulic unit made of three components: the impluvium, the terrace and the dyke. The impluvium or the catchment is the area which collects and conveys runoff water. It is bordered by a natural water divide line (a line that demarcates the boundary of a natural area or catchment, so that all the rain that falls on this area is concentrated and drained towards the same outlet). Each unit has its own impluvium, but can also receive excess water from upstream units. The terrace or cropping zone is the area in which farming is practised. It is formed progressively by the deposition of sediment. An artificial soil will then be created, which can be up to 5 m deep close to the dyke. Generally, fruit trees (e.g. olive, fig, almond, and date palm), legumes (e.g. pea, chickpeas, lentil, and faba bean) and barley and wheat are cultivated on these terraces.
Purpose of the Technology: Although the jessour technique was developed for the production of various agricultural crops, it now also plays three additional roles: (1) aquifer recharge, via runoff water infiltration into the terraces, (2) flood control and therefore the protection of infrastructure and towns built downstream, and (3) wind erosion control, by preventing sediment from reaching the downstream plains, where windspeeds can be particularly high.
Establishment / maintenance activities and inputs: In the Jessour, a dyke (tabia, sed, katra) acts as a barrier used to hold back sediment and runoff water. Such dykes are made of earth, and are equipped with a central and/or lateral spillway (masref and/or manfes) and one or two abutments (ktef), assuring the evacuation of excess water. They are trapezoidal and measure 15-50 m in length, 1-4 m in width and 2-5 m in height. In old units, the dyke is stabilised with a covering of dry stones to overcome the erosive effects of water wave action on the front and back of the dyke. The spillway is made of stones arranged in the form of stairs, in order to dissipate the kinetic energy of the overflow.
This technology is currently encountered in the mountain ranges of Matmata of South Eastern Tunisia where the local agricultural activities are based mainly on rainfed agriculture and livestock breeding. However, high rates of migration to cities may threaten the long-term maintenance of those structures.
Location: Beni Khedache, Medenine, Tunisia
No. of Technology sites analysed:
Spread of the Technology: evenly spread over an area (approx. 100-1,000 km2)
In a permanently protected area?:
Date of implementation: more than 50 years ago (traditional)
Type of introduction
| Specify input | Unit | Quantity | Costs per Unit (TD) | Total costs per input (TD) | % of costs borne by land users |
| Labour | |||||
| Labour | ha | 1.0 | 1200.0 | 1200.0 | 100.0 |
| Plant material | |||||
| ha | 1.0 | 800.0 | 800.0 | 100.0 | |
| Construction material | |||||
| ha | 1.0 | 1000.0 | 1000.0 | 100.0 | |
| Total costs for establishment of the Technology | 3'000.0 | ||||
| Total costs for establishment of the Technology in USD | 2'307.69 | ||||
| Specify input | Unit | Quantity | Costs per Unit (TD) | Total costs per input (TD) | % of costs borne by land users |
| Labour | |||||
| Labour | ha | 1.0 | 400.0 | 400.0 | 100.0 |
| Plant material | |||||
| ha | 1.0 | 200.0 | 200.0 | 100.0 | |
| Construction material | |||||
| ha | 1.0 | 300.0 | 300.0 | 100.0 | |
| Total costs for maintenance of the Technology | 900.0 | ||||
| Total costs for maintenance of the Technology in USD | 692.31 | ||||
Reduced grazing lands
Reduced available runoff for downstream users
