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

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

Soil protection and rehabilitation for food security (ProSo(i)l)

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

Direction Générale de l’Amenagement et de Conservation des Terres Agricoles (DG/ACTA) - Tunisia

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

GIZ Tunisia (GIZ Tunisia) - Tunisia

1.3 Conditions regarding the use of data documented through WOCAT

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

Yes

1.4 Declaration on sustainability of the described Technology

Is the Technology described here problematic with regard to land degradation, so that it cannot be declared a sustainable land management technology?

No

1.5 Reference to Questionnaire(s) on SLM Approaches (documented using WOCAT)

2.1 Short description of the Technology

Definition of the Technology:

The biological consolidation of embankments is an agricultural practice that entails planting embankments with arboricultural, pastoral, or forage species. This cultivation technique enhances the effectiveness and longevity of these structures.

2.2 Detailed description of the Technology

Description:

Anti-erosion banks are widespread in central Tunisia. In semi-arid environments, these structures consist of earthen levees built perpendicular to the slope of the land accompanied by a channel designed to retain runoff water and sediment between the banks.
Implementing and maintaining these structures can be financially burdensome for farmers, necessitating biological consolidation to ensure their long-term viability. Consolidation can be achieved using various types of tree, pasture and fodder plantations. Successful biological consolidation is contingent on factors such as soil type (nature, relief), climate (particularly annual rainfall), irrigation water resources and the species chosen. Most farmers use olive trees to consolidate soil and water conservation structures in their plots.
Consolidation efforts encompass both recent and aging structures, focusing on rehabilitation and ongoing maintenance. Planting occurs on the embankments and within their channels, providing essential plant cover and root systems that bind soil particles, reducing the risk of erosion. This technique has proven to enhance soil fertility, boost crop yields, and generate income for farmers through the sale of olives and olive oil. Despite the 10-15% loss of land surface associated with embankment installation, the consolidation process increases the overall value of the land. The presence of olive trees enhances the land's worth.

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

Indicate year of implementation:

1998

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• as part of a traditional system (> 50 years)
• through projects/ external interventions

Comments (type of project, etc.):

National Soil and Water Conservation Strategy

3.1 Main purpose(s) of the Technology

• improve production
• reduce, prevent, restore land degradation
• protect a watershed/ downstream areas – in combination with other Technologies
• create beneficial economic impact

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

Land use mixed within the same land unit:

Yes

Specify mixed land use (crops/ grazing/ trees):

• Agro-pastoralism (incl. integrated crop-livestock)

3.3 Has land use changed due to the implementation of the Technology?

Has land use changed due to the implementation of the Technology?

• Yes (Please fill out the questions below with regard to the land use before implementation of the Technology)

Land use mixed within the same land unit:

No

Comments:

The installation of mechanical embankments has encouraged farmers to exploit their lands and plant them with olive trees.

3.4 Water supply

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

• mixed rainfed-irrigated

3.5 SLM group to which the Technology belongs

• improved ground/ vegetation cover
• integrated soil fertility management
• cross-slope measure

3.6 SLM measures comprising the Technology

3.7 Main types of land degradation addressed by the Technology

3.8 Prevention, reduction, or restoration of land degradation

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

• reduce land degradation
• restore/ rehabilitate severely degraded land

4.1 Technical drawing of the Technology

4.2 General information regarding the calculation of inputs and costs

Specify how costs and inputs were calculated:

• per Technology area

other/ national currency (specify):

Tunisian dinars

If relevant, indicate exchange rate from USD to local currency (e.g. 1 USD = 79.9 Brazilian Real): 1 USD =:

3.1

4.3 Establishment activities

	Activity	Timing (season)
1.	Purchase olive seedlings
2.	Preparing holes
3.	Planting

4.4 Costs and inputs needed for establishment

If you are unable to break down the costs in the table above, give an estimation of the total costs of establishing the Technology:

600.0

If land user bore less than 100% of costs, indicate who covered the remaining costs:

Directorate-General for the Development and Conservation of Agricultural Lands

4.5 Maintenance/ recurrent activities

	Activity	Timing/ frequency
1.	Weed clearance
2.	Prunning
3.	Irrigation

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

If you are unable to break down the costs in the table above, give an estimation of the total costs of maintaining the Technology:

1000.0

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

- Availability of workers

5.1 Climate

5.2 Topography

Indicate if the Technology is specifically applied in:

• not relevant

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.

Organic carbon in topsoil (wt.%): 1
Topsoil pH (H2O): 8
Topsoil calcium carbonate (wt.%): 43.4
Subsoil organic carbon (wt.%): 0.35
Subsoil pH (H2O): 8.3
Subsoil calcium carbonate (wt.%): 62.7

5.4 Water availability and quality

Is water salinity a problem?

Yes

Is flooding of the area occurring?

No

5.5 Biodiversity

5.6 Characteristics of land users applying the Technology

5.7 Average area of land used 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

Are land use rights based on a traditional legal system?

Yes

Specify:

Heritage

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

Soil

Climate and disaster risk reduction

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	increase or decrease	How does the Technology cope with it?
seasonal rainfall	wet/ rainy season	decrease	very 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

• 11-50%

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

• 0-10%

6.6 Adaptation

Has the Technology been modified recently to adapt to changing conditions?

No

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the land user’s view
Profitability: Planting olive trees is a profitable activity for land users and involves relatively low expense.
Preservation of cultural heritage: Planting olive trees is of cultural importance in Tunisia. Embracing this method of cultivation allows land users to safeguard cultural heritage and uphold traditional agricultural practices.
Sustainability: ensures the longevity of the embankments

Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
Olive trees are carbon sinks that help offset greenhouse gas emissions.
Reinforce and extend the service life of embankments.
Olive trees provide opportunities to develop value-added products such as olive oil, table olives and olive-based cosmetics.

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?
Olive trees are suited to specific climatic conditions and can be sensitive to various environmental hazards, such as extreme temperatures, drought, frost or pests and diseases.	Land users must select appropriate olive varieties that are well suited to their local climatic conditions.

Weaknesses/ disadvantages/ risks in the compiler’s or other key resource person’s view	How can they be overcome?
Successful implementation of the technology hinges on suitable environmental conditions, including appropriate soil types, climatic factors and access to water resources.	Feasibility studies to determine the suitability of the land for olive tree planting

7.1 Methods/ sources of information

7.2 References to available publications

Title, author, year, ISBN:

Guide de conservation des eaux et du Sol, Ministère de l’agriculture, Direction Générale de l'Aménagement et de la Conservations des Terres Agricoles, 1995: Ministère de l’agriculture, Direction Générale de l'Aménagement et de la Conservations des Terres Agricoles

Available from where? Costs?

Ministry of Agriculture, Directorate-General for the Development and Conservation of Agricultural Lands

Title, author, year, ISBN:

Carte agricole de la Tunisie, Ministère de l’agriculture, 2005

Available from where? Costs?

Ministry of Agriculture, Directorate-General for the Development and Conservation of Agricultural Lands

Title, author, year, ISBN:

Analyse du système des banquettes mécaniques Propositions d'améliorations, de valorisation et d'évolution pour les gouvernorats de Kairouan, Siliana et Zaghouan, Tunisie, Eric Roose, 2002

Available from where? Costs?

Ministry of Agriculture, Directorate-General for the Development and Conservation of Agricultural Lands

7.3 Links to relevant online information

Title/ description:

Harmonized World Soil Database (HWSD), FAO, 2008

URL:

https://www.fao.org/soils-portal/data-hub/soil-maps-and-databases/harmonized-world-soil-database-v12/en/