Technologies

Amendement sableux dans le système oasien [Tunisia]

Erradm

technologies_3732 - Tunisia

Completeness: 90%

1. General information

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

Key resource person(s)

land user:

Ben Abdelkader Mohamed

Tunisia

SLM specialist:

Saadallah Jamila

Commissariat Régional au Développement Agricole de Kebili

Tunisia

SLM specialist:

Karbout Nissaf

Institut des Régions Arides

Tunisia

{'additional_translations': {}, 'value': 1, 'label': 'Name of project which facilitated the documentation/ evaluation of the Technology (if relevant)', 'text': 'Decision Support for Mainstreaming and Scaling out Sustainable Land Management (GEF-FAO / DS-SLM)', 'template': 'raw'} {'additional_translations': {}, 'value': 6152, 'label': 'Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)', 'text': 'Commissariat Régional au Développement Agricole de Kebili (CRDA) - Tunisia', 'template': 'raw'}

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. Description of the SLM Technology

2.1 Short description of the Technology

Definition of the Technology:

Amendement sableux consiste à améliorer la fertilité de sol pour améliorer la production.

2.2 Detailed description of the Technology

Description:

Le dattier est une espèce termophile, son activité se manifeste à partir de 10°C, le dattier est cultivé comme arbre fruitier dans les régions arides et semi-arides chaudes, le dattier peut donc supporter des températures tres élevées. La fructification du dattier ne peut s'effectuer dans de bornes conditions que pendant l'époque de l'année la plus chaude pendant laquelle l'humidité relative de l'air est faible et la pluviométrie est nulle.
Le palmier résiste à l'eau chargée, en sel, qui est indispensable même à sa croissance. Les besoins en eau sont les plus élevés de toutes les fruitières 15000 à 2500 m3/an/ha. Pour D.N les besoins sont de 23.647 m3/ha/ an. 1 kg de dattes nécessite 1m3 d'eau. Il faut un débit moyen annuel continu de 0,5 à 0,6 l/s.
Le dattier est assez peu exigent sur la qualité du sol, bien que relativement résistante à l'asphyxie ses racines ne peuvent pas végéter dans l'eau stagnant, en effet dans les oasis le manque de drainage entraîne rapidement la salure du sol et la stérilité du terrain ceci est d'autant plus vrai qu'il s'agit de terre lourde. Dans le Djerid un réseau de drainage (à ciel ouvert) à 2,5 m de profondeur et distant de 150 à 200 m est suffisant pour assurer une bonne culture.
Le Dattier redoute les pluies et humidité atmosphérique pendant les périodes de pleine floraison et de développement du fruit, ces conditions constituent des limites à sa culture au même titre que le manque de chaleur estivale. Pendant la floraison une forte humidité favorise la pourriture des inflorescences et gène la germination des grains de pollen. Pendant la maturation elle diminue la transpiration des dattes, les fruits restent gorgés d'eau peuvent éclater. La pulpe en contact avec l'air va fermenter et pourrit.
Suite à la dégradation des oasis à cause de l’hydromorphie, salinité, remonté de la nappe.
La qualité primordiale du sol d'une palmeraie est la perméabilité, qu'elle soit irriguée ou alimentée directement par la nappe phréatique. Le choix du sol devra donc etre orienté vers les sols légers, les sables, sables limoneux, les limons sableux à faible teneur en argile (moins de 10 %). Les sols lourds, argileux, rocheux ou caillouteux sont à rejeter.
Lorsque la plantation ne dépend pas directement de la nappe phréatique, le sol doit avoir une profondeur minimale de 1,50 m à 2 m.
Pour cette raison, les agriculteurs ont créé la technique de l’amendement sableux, pour lutter contre les formes de dégradation de la fertilité du sol et la dégradation des palmiers dattiers.
La technique de l’amendement consiste à apporter le sable des dunes les plus proches pour créer un nouveau substrat pour le palmier dattier.

2.3 Photos of the Technology

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

Country:

Tunisia

Region/ State/ Province:

Kébili

Specify the spread of the Technology:
  • evenly spread over an area
If precise area is not known, indicate approximate area covered:
  • < 0.1 km2 (10 ha)

2.6 Date of implementation

If precise year is not known, indicate approximate date:
  • less than 10 years ago (recently)

2.7 Introduction of the Technology

Specify how the Technology was introduced:
  • as part of a traditional system (> 50 years)

3. Classification of the SLM Technology

3.1 Main purpose(s) of the Technology

  • improve production
  • reduce, prevent, restore land degradation
  • conserve ecosystem
  • preserve/ improve biodiversity
  • adapt to climate change/ extremes and its impacts
  • mitigate climate change and its impacts
  • create beneficial economic impact
  • create beneficial social 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):
  • Agroforestry

Cropland

Cropland

  • Perennial (non-woody) cropping
  • Tree and shrub cropping
Tree and shrub cropping - Specify crops:
  • dates
  • fruits, other
  • grapes
Number of growing seasons per year:
  • 1
Grazing land

Grazing land

Extensive grazing:
  • Ranching
Intensive grazing/ fodder production:
  • Cut-and-carry/ zero grazing
Animal type:
  • goats
  • camels
  • sheep
  • Élevage ovin, camelin et caprin.
  • Système oasien composé de 3 étages: - Palmier dattier. - Grenadier, vigne et pommier... - Cultures maraichères.

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)
Comments:

Addition des cultures maraichage aprés l'introduction de la technologie de l'amendement sableux.

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

  • integrated soil fertility management
  • improved plant varieties/ animal breeds
  • irrigation management (incl. water supply, drainage)

3.6 SLM measures comprising the Technology

agronomic measures

agronomic measures

  • A1: Vegetation/ soil cover
  • A2: Organic matter/ soil fertility
  • A3: Soil surface treatment
vegetative measures

vegetative measures

  • V1: Tree and shrub cover
  • V2: Grasses and perennial herbaceous plants
  • V4: Replacement or removal of alien/ invasive species
structural measures

structural measures

  • S3: Graded ditches, channels, waterways
  • S6: Walls, barriers, palisades, fences
  • S7: Water harvesting/ supply/ irrigation equipment
management measures

management measures

  • M1: Change of land use type
  • M3: Layout according to natural and human environment
  • M5: Control/ change of species composition
  • M6: Waste management (recycling, re-use or reduce)

3.7 Main types of land degradation addressed by the Technology

soil erosion by water

soil erosion by water

  • Wt: loss of topsoil/ surface erosion
soil erosion by wind

soil erosion by wind

  • Et: loss of topsoil
chemical soil deterioration

chemical soil deterioration

  • Cn: fertility decline and reduced organic matter content (not caused by erosion)
  • Cs: salinization/ alkalinization
physical soil deterioration

physical soil deterioration

  • Pi: soil sealing
  • Pw: waterlogging
biological degradation

biological degradation

  • Bc: reduction of vegetation cover
  • Bh: loss of habitats
  • Bq: quantity/ biomass decline
  • Bs: quality and species composition/ diversity decline
  • Bl: loss of soil life
water degradation

water degradation

  • Ha: aridification

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
Comments:

L'amendement ne fait que lorsque les terres ont été déjà affecté par la dégradation.

4. Technical specifications, implementation activities, inputs, and costs

4.1 Technical drawing of the Technology

{'additional_translations': {}, 'content_type': None, 'preview_image': '', 'key': 'Technical drawing', 'value': None, 'template': 'raw'}
Technical specifications (related to technical drawing):

Densité des palmiers est 8 m * 8 m (C'est le meilleur espacement pour les palmiers dattiers).
L'apport des sables se fait par camion, pour amender 40 cm d'hauteur dans la première fois, puis aprés ça devient juste quelques centimètres juste pour entretenir le substrat du palmier et garder les racines couvertes.

Author:

Donia Jendoubi & Nissaf Karbout

Date:

2018

4.2 General information regarding the calculation of inputs and costs

Specify how costs and inputs were calculated:
  • per Technology area
Indicate size and area unit:

ha

other/ national currency (specify):

Dinar Tunisien

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

2.45

Indicate average wage cost of hired labour per day:

20 - 25 TDN

4.3 Establishment activities

Activity Timing (season)
1. Désherbage (supression des mauvaises herbes)
2. Labour 30 - 40 cm
3. Séchage du sol
4. Apport des sables (40 cm)
5. Épandage
6. Labour pour malaxage
7. Confection des cuvettes des palmiers
8. Irrigation

4.4 Costs and inputs needed for establishment

Specify input Unit Quantity Costs per Unit Total costs per input % of costs borne by land users
Labour Désherbage personne/jour 60.0 25.0 1500.0 1000.0
Labour Confection des cuvettes personne/jour 74.0 25.0 1850.0 100.0
Equipment Transport par camions camion 350.0 40.0 14000.0 100.0
Equipment Traction heure 80.0 20.0 1600.0 100.0
Equipment Épandage heure 80.0 20.0 1600.0 100.0
Other Eau (tour d'irrigation) an 1.0 600.0 600.0 100.0
Total costs for establishment of the Technology 21150.0
Total costs for establishment of the Technology in USD 8632.65

4.5 Maintenance/ recurrent activities

Activity Timing/ frequency
1. Désherbage (supression des mauvaises herbes)
2. Labour 30 - 40 cm
3. Séchage du sol
4. Apport des sables (moins que 40 cm)
5. Épandage
6. Labour pour malaxage
7. Confection des cuvettes des palmiers
8. Irrigation

4.6 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 Désherbage personne/jour 60.0 25.0 1500.0 100.0
Labour Confection des cuvettes personne/jour 74.0 25.0 1850.0 100.0
Equipment Transport par camions camion 100.0 40.0 4000.0 100.0
Equipment Traction heure 80.0 20.0 1600.0 100.0
Equipment Épandage heure 25.0 20.0 500.0 100.0
Other Eau (Tour d'irrigation) an 1.0 600.0 600.0 100.0
Total costs for maintenance of the Technology 10050.0
Total costs for maintenance of the Technology in USD 4102.04
Comments:

L'entretien commence aprés 5 à 10 ans. Et ça dépend de la couche d'amendement.

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

Le cout d'apport est devenu plus cher (transport), ainsi que le cout de la main d'oeuvre.

5. Natural and human environment

5.1 Climate

Annual rainfall
  • < 250 mm
  • 251-500 mm
  • 501-750 mm
  • 751-1,000 mm
  • 1,001-1,500 mm
  • 1,501-2,000 mm
  • 2,001-3,000 mm
  • 3,001-4,000 mm
  • > 4,000 mm
Specify average annual rainfall (if known), in mm:

90.00

Indicate the name of the reference meteorological station considered:

Centre de Kébili.

Agro-climatic zone
  • arid

5.2 Topography

Slopes on average:
  • flat (0-2%)
  • gentle (3-5%)
  • moderate (6-10%)
  • rolling (11-15%)
  • hilly (16-30%)
  • steep (31-60%)
  • very steep (>60%)
Landforms:
  • plateau/plains
  • ridges
  • mountain slopes
  • hill slopes
  • footslopes
  • valley floors
Altitudinal zone:
  • 0-100 m a.s.l.
  • 101-500 m a.s.l.
  • 501-1,000 m a.s.l.
  • 1,001-1,500 m a.s.l.
  • 1,501-2,000 m a.s.l.
  • 2,001-2,500 m a.s.l.
  • 2,501-3,000 m a.s.l.
  • 3,001-4,000 m a.s.l.
  • > 4,000 m a.s.l.
Indicate if the Technology is specifically applied in:
  • convex situations
Comments and further specifications on topography:

La région de Nefzawa est une toposéquence: le point le plus haut c'est l'oasis de Douz et la région la plus bas est l'oasis de Fatnassa.

5.3 Soils

Soil depth on average:
  • very shallow (0-20 cm)
  • shallow (21-50 cm)
  • moderately deep (51-80 cm)
  • deep (81-120 cm)
  • very deep (> 120 cm)
Soil texture (topsoil):
  • coarse/ light (sandy)
Soil texture (> 20 cm below surface):
  • coarse/ light (sandy)
Topsoil organic matter:
  • low (<1%)
If available, attach full soil description or specify the available information, e.g. soil type, soil PH/ acidity, Cation Exchange Capacity, nitrogen, salinity etc.

Encoutement gypseux au delà de 60 cm.

5.4 Water availability and quality

Ground water table:

> 50 m

Availability of surface water:

poor/ none

Water quality (untreated):

for agricultural use only (irrigation)

Is water salinity a problem?

Yes

Specify:

C'est le majeur problème.

Is flooding of the area occurring?

No

Comments and further specifications on water quality and quantity:

Pompage profond de la nappe continentale intercalaire, qui a une température supérieure à 60 °C.

5.5 Biodiversity

Species diversity:
  • low
Habitat diversity:
  • low

5.6 Characteristics of land users applying the Technology

Sedentary or nomadic:
  • Sedentary
Market orientation of production system:
  • mixed (subsistence/ commercial)
Off-farm income:
  • 10-50% of all income
Relative level of wealth:
  • average
Individuals or groups:
  • individual/ household
Level of mechanization:
  • mechanized/ motorized
Gender:
  • men
Age of land users:
  • middle-aged
Indicate other relevant characteristics of the land users:

L'exploitant de terre est un entrepreneur des batiments aussi.

5.7 Average area of land used by land users applying the Technology

  • < 0.5 ha
  • 0.5-1 ha
  • 1-2 ha
  • 2-5 ha
  • 5-15 ha
  • 15-50 ha
  • 50-100 ha
  • 100-500 ha
  • 500-1,000 ha
  • 1,000-10,000 ha
  • > 10,000 ha
Is this considered small-, medium- or large-scale (referring to local context)?
  • medium-scale

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

Land ownership:
  • individual, titled
Land use rights:
  • individual
Water use rights:
  • communal (organized)

5.9 Access to services and infrastructure

health:
  • poor
  • moderate
  • good
education:
  • poor
  • moderate
  • good
technical assistance:
  • poor
  • moderate
  • good
employment (e.g. off-farm):
  • poor
  • moderate
  • good
markets:
  • poor
  • moderate
  • good
energy:
  • poor
  • moderate
  • good
roads and transport:
  • poor
  • moderate
  • good
drinking water and sanitation:
  • poor
  • moderate
  • good
financial services:
  • poor
  • moderate
  • good

6. Impacts and concluding statements

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

crop production

decreased
increased

crop quality

decreased
increased

forest/ woodland quality

decreased
increased

risk of production failure

increased
decreased

product diversity

decreased
increased

production area

decreased
increased

land management

hindered
simplified
Income and costs

expenses on agricultural inputs

increased
decreased

farm income

decreased
increased

diversity of income sources

decreased
increased

economic disparities

increased
decreased

workload

increased
decreased

Socio-cultural impacts

food security/ self-sufficiency

reduced
improved

land use/ water rights

worsened
improved

SLM/ land degradation knowledge

reduced
improved

conflict mitigation

worsened
improved
Comments/ specify:

À cause de nivellement par rapport aux parcelles voisins.

situation of socially and economically disadvantaged groups

worsened
improved
Comments/ specify:

Les petits agriculteurs ne sont pas capables de faire l'amendement sableux.

Ecological impacts

Water cycle/ runoff

excess water drainage

reduced
improved

evaporation

increased
decreased
Soil

soil moisture

decreased
increased

soil cover

reduced
improved

soil loss

increased
decreased

soil accumulation

decreased
increased

soil crusting/ sealing

increased
reduced

soil compaction

increased
reduced

nutrient cycling/ recharge

decreased
increased

salinity

increased
decreased

soil organic matter/ below ground C

decreased
increased

acidity

increased
reduced
Biodiversity: vegetation, animals

Vegetation cover

decreased
increased

biomass/ above ground C

decreased
increased

plant diversity

decreased
increased

habitat diversity

decreased
increased
Climate and disaster risk reduction

drought impacts

increased
decreased

impacts of cyclones, rain storms

increased
decreased

emission of carbon and greenhouse gases

increased
decreased

wind velocity

increased
decreased

micro-climate

worsened
improved

6.2 Off-site impacts the Technology has shown

damage on neighbours' fields

increased
reduced
Comments/ specify:

Nivellement par rapport aux parcelles voisins.

damage on public/ private infrastructure

increased
reduced
Comments/ specify:

Problème d'hydromorphie.

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?
annual temperature increase very well
seasonal temperature dry season increase very well
annual rainfall decrease well
seasonal rainfall wet/ rainy season decrease well

Climate-related extremes (disasters)

Climatological disasters
How does the Technology cope with it?
drought very well
Biological disasters
How does the Technology cope with it?
epidemic diseases very well

Other climate-related consequences

Other climate-related consequences
How does the Technology cope with it?
reduced growing period very well
Comments:

L'amendement sableux a un effet positif et rapide sur la croissance de palmier dattier et sa vigueur.

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?
Short-term returns:

negative

Long-term returns:

positive

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?
Short-term returns:

slightly negative

Long-term returns:

positive

6.5 Adoption of the Technology

  • > 50%
Of all those who have adopted the Technology, how many did so spontaneously, i.e. without receiving any material incentives/ payments?
  • 91-100%
Comments:

Selon les moyens financiers des agriculteurs.

6.6 Adaptation

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

Yes

If yes, indicate to which changing conditions it was adapted:
  • changing markets
Specify adaptation of the Technology (design, material/ species, etc.):

Il y a une grande demande pour appliquer l'amendement sableux parce que le valeur des dattes et trés haut et rentable.

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the land user’s view
Production amélioré.
Fertilité du sol amélioré.
Amélioration de l'oasis (addition des cultures maraichères).
Protection des palmiers contre l'hydromorphie et la salinité du sol.
Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
Amélioration de vigueur et production des palmiers.
Augmentation du tronc du palmier et augmentation des nombres des régines de 6 jusqu'à 8.
Réduction de l'hydromorphie et la salinité.
Stabiliser le pH dans le sol et amélioration des caractéristiques physico-chimique du sol.
Amélioration de qualité et quantité des dattes.

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?
Beaucoup des dépenses. Appui et subvention de la ministère d'agriculture (déjà en cours).
Manque d'encadrement et conseil. Organiser des journées de formation et conseils.
Weaknesses/ disadvantages/ risks in the compiler’s or other key resource person’s view How can they be overcome?
Apport de sable non controlé. Régler et controler l'activité d'apport des sables.
Déséquilibre d'écosystème. Aménagement des sites pour l'apport des sables qui doivent ètre gérés par des lois.
Méthodes non uniformes, anarchiques et traditionnelles (non étudié). Harmonisation de la méthode par des bases scientifiques.
Pas de suivi et évaluation. Appui, conseil et accompagnement de l'agriculteur et sa formation sur la production et la qualité du sol.

7. References and links

7.1 Methods/ sources of information

  • field visits, field surveys

2 agriculteurs.

  • interviews with land users

2 agriculteurs.

  • interviews with SLM specialists/ experts

8 spécialistes de CRDA de Kébili.

7.3 Links to relevant online information

Title/ description:

La filière des dattes communes dans les oasis de Gabès dans le contexte des aléas climatiques et économiques: fonctionnement, atouts et contraintes

URL:

https://www.memoireonline.com/02/12/5304/m_La-filiere-des-dattes-communes-dans-les-oasis-de-Gabes-dans-le-contexte-des-aleas-climatiques-et20.html

Title/ description:

Dans les oasis de Nafzoua

URL:

https://www.rcp-sirma.org/content/download/4236/31621/version/1/file/Exposition+Nefzaoua.pdf

Title/ description:

De l’identification des contraintes environnemental es à l’évaluation des performances agronomiques dans un système irrig ué collectif. Cas de l’oasis de Fatnassa (Nefzaoua, sud tunisien)

URL:

https://tel.archives-ouvertes.fr/tel-00473373/document

Links and modules

Expand all Collapse all

Modules