1.2 Contact details of resource persons and institutions involved in the assessment and documentation of the Technology

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)

Institut des Régions Arides de Médenine (Institut des Régions Arides de Médenine) - Tunisia

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)

Commissariats Régionaux au Développement Agricole (CRDA) - Tunisia

1.3 Conditions regarding the use of data documented through WOCAT

When were the data compiled (in the field)?

22/09/2008

The compiler and key resource person(s) accept the conditions regarding the use of data documented through WOCAT:

Yes

2.1 Short description of the Technology

Definition of the Technology:

Jessour is an ancient runoff water harvesting technique widely practiced in the arid highlands

2.2 Detailed description of the Technology

Description:

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.

2.3 Photos of the Technology

2.5 Country/ region/ locations where the Technology has been applied and which are covered by this assessment

2.6 Date of implementation

If precise year is not known, indicate approximate date:

• more than 50 years ago (traditional)

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• as part of a traditional system (> 50 years)

Comments (type of project, etc.):

Jessour is an ancient runoff water harvesting technique widely practiced in the arid highlands, which are dominated by outcroppings of calcareous formations and depositions of quaternary calcareous silt.

3.2 Current land use type(s) where the Technology is applied

Comments:

Major land use problems (compiler’s opinion): Loss of surface water (runoff), problems of flooding, water erosion, soil degradation, drought

Future (final) land use (after implementation of SLM Technology): Cropland: Ct: Tree and shrub cropping

Livestock is grazing on crop residues

If land use has changed due to the implementation of the Technology, indicate land use before implementation of the Technology:

Grazing land: Ge: Extensive grazing land

3.3 Further information about land use

Water supply for the land on which the Technology is applied:

• rainfed

Comments:

Water supply: rainfed, mixed rainfed - irrigated

Number of growing seasons per year:

• 1

Specify:

Longest growing period in days: 180Longest growing period from month to month: Oct - Mar

3.4 SLM group to which the Technology belongs

• windbreak/ shelterbelt
• water harvesting
• irrigation management (incl. water supply, drainage)

3.5 Spread of the Technology

Specify the spread of the Technology:

• evenly spread over an area

If the Technology is evenly spread over an area, indicate approximate area covered:

• 100-1,000 km2

Comments:

This technology is developed mainly in the upstream areas of the study watershed (mountainous zone of Béni Khédache). This system is based on runoff water harvesting for fruit trees cropping (mainly olives). The cropping areas are relatively small and rarely exceed 0.25 ha.

3.6 SLM measures comprising the Technology

Comments:

Main measures: structural measures

3.7 Main types of land degradation addressed by the Technology

Comments:

Main type of degradation addressed: Wt: loss of topsoil / surface erosion

Secondary types of degradation addressed: Wg: gully erosion / gullying

Main causes of degradation: crop management (annual, perennial, tree/shrub), change of seasonal rainfall, Heavy / extreme rainfall (intensity/amounts), poverty / wealth

Secondary causes of degradation: soil management, overgrazing, land tenure

3.8 Prevention, reduction, or restoration of land degradation

Specify the goal of the Technology with regard to land degradation:

• prevent land degradation
• reduce land degradation

Comments:

Main goals: mitigation / reduction of land degradation
Secondary goals: prevention of land degradation

4.1 Technical drawing of the Technology

4.2 Technical specifications/ explanations of technical drawing

Left: Cross-section of dyke (locally called tabia) and terrace (cropping area).
The Jessour ensure the collection of both runoff water and sediments allowing creating very deep ‘artificial’ soils (terrace) which form a very good reservoir for water and nutrients to be used by fruit trees and annual crops.
Right: The spillway allows the overflow to the other Jessour downstream. It also represents the symbol of water sharing equity between different farmers in the same watershed. (Drawing adapted from El Amami (1984))

Location: Mountainous zone near Beni Khedache. Medenine

Date: 1984

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: moderate

Main technical functions: increase of infiltration, sediment retention / trapping, sediment harvesting, harvesting of runoff water / water trapping

Secondary technical functions: control of concentrated runoff: retain / trap, improvement of ground cover, increase / maintain water stored in soil, increase of groundwater level / recharge of groundwater, increase of biomass (quantity)

Spillway
Height of bunds/banks/others (m): 2-5
Width of bunds/banks/others (m): 0.4-0.6
Length of bunds/banks/others (m): 2-6

Dam/ pan/ pond
Vertical interval between structures (m): 2-3
Spacing between structures (m): 30-70
Height of bunds/banks/others (m): 2-6
Width of bunds/banks/others (m): 1-5
Length of bunds/banks/others (m): 10-40

Construction material (earth): Main dyke

Construction material (stone): Spillway and in some cases the dyke (external coating)

Construction material (concrete): Occasionally for consolidation of the spillway.

Lateral gradient along the structure: <1%

Specification of dams/ pans/ ponds: Capacity 300-1000m3

Catchment area: 1-10ham2

Beneficial area: 0.01-1ham2

For water harvesting: the ratio between the area where the harvested water is applied and the total area from which water is collected is: 1:5

4.3 General information regarding the calculation of inputs and costs

other/ national currency (specify):

TD

Indicate exchange rate from USD to local currency (if relevant): 1 USD =:

1.3

4.4 Establishment activities

	Activity	Type of measure	Timing
1.	Dyke construction	Structural
2.	Plantations	Structural
3.	Spillway construction	Structural

4.5 Costs and inputs needed for establishment

	Specify input	Unit	Quantity	Costs per Unit	Total costs per input	% 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					3000.0

Comments:

Duration of establishment phase: 6 month(s)

4.6 Maintenance/ recurrent activities

	Activity	Type of measure	Timing/ frequency
1.	Crop and trees maintenance	Structural	Annually
2.	Dyke and spillway maintenance	Structural
3.	Repairs	Structural
4.	Tillage (against soil sealing)	Structural
5.	Tillage (against soil sealing)	Structural	Annually and after rainy events

4.7 Costs and inputs needed for maintenance/ recurrent activities (per year)

	Specify input	Unit	Quantity	Costs per Unit	Total costs per input	% 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

Comments:

Machinery/ tools: Tractor, animals and manual works.

The technology establishment and maintenance costs met by the land users are 100% if executed on a private basis, but it can range from 10 to 50% when the site is subject to a publicly-funded programme.

4.8 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

Found in inaccessible and even remote areas, labour is the most determining factors affecting the costs of this system.

5.1 Climate

5.2 Topography

Comments and further specifications on topography:

Altitudinal zone: 101-500 m a.s.l. (This is the most appropriate location)
Landforms: Mountain slopes (This is the most appropriate location)

5.3 Soils

If available, attach full soil description or specify the available information, e.g. soil type, soil PH/ acidity, Cation Exchange Capacity, nitrogen, salinity etc.

Soil depth: Very shallow-shallow. Very deep in particular case of loess deposits.
Soil fertility is: Very low
Soil drainage/infiltration is: Medium
Soil water storage: Medium

5.4 Water availability and quality

Comments and further specifications on water quality and quantity:

Water quality untreated: Poor drinking water (treatement required) (ground water better than surface water (cisterns))

5.5 Biodiversity

5.6 Characteristics of land users applying the Technology

Indicate other relevant characteristics of the land users:

Land users applying the Technology are mainly common / average land users
Difference in the involvement of women and men: Historically, the hard work is done by men.
Population density: 10-50 persons/km2
Annual population growth: < 0.5%
10% of the land users are rich and own 20% of the land.
80% of the land users are average wealthy and own 75% of the land.
10% of the land users are poor and own 5% of the land.
Off-farm income specification: The technique is very ancient and, therefore, ALL the farmers apply this technology. The only difference is the number of the owned units.
Off-farm incomes come from migration, construction works, commerce, tourism sector, administration or informal activities.
Level of mechanization: Manual work and animal traction (Especially in remote areas with difficult access)

5.7 Average area of land owned or leased by land users applying the Technology

5.8 Land ownership, land use rights, and water use rights

Land ownership:

• individual, not titled

Land use rights:

• individual

Water use rights:

• individual

Comments:

The communal rule applies in this region: the farmer owns the terrace (the cropping area) and its impluvium from which the runoff is harvested.

5.9 Access to services and infrastructure

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Socio-cultural impacts

Ecological impacts

Water cycle/ runoff

Soil

6.2 Off-site impacts the Technology has shown

6.3 Exposure and sensitivity of the Technology to gradual climate change and climate-related extremes/ disasters (as perceived by land users)

Gradual climate change

Gradual climate change

	Season	Type of climatic change/ extreme	How does the Technology cope with it?
annual temperature		increase	well

Climate-related extremes (disasters)

Meteorological disasters

	How does the Technology cope with it?
local rainstorm	well
local windstorm	well

Climatological disasters

	How does the Technology cope with it?
drought	well

Hydrological disasters

	How does the Technology cope with it?
general (river) flood	not well

Other climate-related consequences

Other climate-related consequences

	How does the Technology cope with it?
reduced growing period	well

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?

6.5 Adoption of the Technology

Of all those who have adopted the Technology, how many have did so spontaneously, i.e. without receiving any material incentives/ payments?

• 90-100%

Comments:

10% of land user families have adopted the Technology with external material support

90% of land user families have adopted the Technology without any external material support

Comments on spontaneous adoption: This technique is very ancient and it is therefore already fully adopted/used in the region.

There is a moderate trend towards spontaneous adoption of the Technology

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the land user’s view
Well known technique by the local population How can they be sustained / enhanced? training of new generations

Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
This technique allowed a expansion of cropping lands in the mountain area How can they be sustained / enhanced? encourage maintenance of existing structure
Allows crop production in very dry environments (with less than 200 mm of rainfall) How can they be sustained / enhanced? encourage maintenance of existing structure
Collects and accumulates water, soil and nutrients behind the tabia and makes it available to crops How can they be sustained / enhanced? encourage maintenance of existing structure
Reduced damage by flooding How can they be sustained / enhanced? encourage maintenance of existing structure
Well adapted technology for the ecological environment How can they be sustained / enhanced? ensure maintenance works

6.8 Weaknesses/ disadvantages/ risks of the Technology and ways of overcoming them

Weaknesses/ disadvantages/ risks in the land user’s view	How can they be overcome?
Productivity of the land is very low	Development of alternative income generation activities.
Land ownership fragmentation	New land access

Weaknesses/ disadvantages/ risks in the compiler’s or other key resource person’s view	How can they be overcome?
Risks related to the climatic changes	It needs to be combined with supplemental irrigation
Risk of local know how disappearence	Trainig of new generations
Land ownership fragmentation	Agrarian reform

7.2 References to available publications

Title, author, year, ISBN:

El Amami, S. 1984. Les aménagements hydrauliques traditionnels en Tunisie. Centre de Recherche en Génie Rural (CRGR), Tunis, Tunisia. 69 pp.

Available from where? Costs?

ENGREF - Tunis

Title, author, year, ISBN:

Ennabli, N. 1993. Les aménagements hydrauliques et hydro-agricoles en Tunisie. Imprimerie Officielle de la République Tunisienne, Tunis, 255 pp.

Available from where? Costs?

INAT - Tunis

Title, author, year, ISBN:

Ben Mechlia, N., Ouessar, M. 2004. Water harvesting systems in Tunisia. In: Oweis, T., Hachum, A., Bruggeman, A. (eds). Indigenous water harvesting in West Asia and North Africa, , ICARDA, Aleppo, Syria, pp: 21-41.

Available from where? Costs?

ICARDA

Title, author, year, ISBN:

Genin, D., Guillaume, H., Ouessar, M., Ouled Belgacem, A., Romagny, B., Sghaier, M., Taamallah, H. (eds) 2006. Entre la désertification et le développement : la Jeffara tunisienne. CERES, Tunis, 351 pp.

Available from where? Costs?

IRA; IRD

Title, author, year, ISBN:

Ouessar M. 2007. Hydrological impacts of rainwater harvesting in wadi Oum Zessar watershed (Southern Tunisia). Ph.D. thesis, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium, 154 pp.

Available from where? Costs?

IRA

Title, author, year, ISBN:

Sghaier, M., Mahdhi, N., De Graaff, J., Ouessar, M. 2002. Economic assessment of soil and water conservation works: case of the wadi Oum Zessar watershed in south-eastern Tunisia.TRMP paper n° 40, Wageningen University, The Netherlands, pp: 101-113.

Available from where? Costs?

IRA