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)

Université catholique de Louvain (Université catholique de Louvain) - Belgium

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

Centre for Agriculture in the Tropics and Subtropics (Centre for Agriculture in the Tropics and Subtropics) - Germany

1.3 Conditions regarding the use of data documented through WOCAT

When were the data compiled (in the field)?

01/08/1999

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:

A combination of three measures to stabilise dunes: area closure, the use of palisades, and vegetative fixation through natural regeneration as
well as planting.

2.2 Detailed description of the Technology

Description:

In the Sahelian zone of Niger, sand dune encroachment can lead to loss of agricultural and pastoral land, and threatens villages. These dunes may form as a result of an increase in wind erosion, but more frequently originate from formerly stabilised dunes that have become mobile again following the disappearance of vegetation. Vegetation loss may occur through a combination of unfavourable climatic conditions and overexploitation by grazing and fuelwood gathering.

Purpose of the Technology: Sustainable dune fixation requires the regeneration of vegetation on the mobile parts of the dunes. For plants to establish, the dunes need to be protected by mechanical measures while being defended against any kind of use. Hence, the technique of dune stabilisation consists of a combination of three measures. These are as follows: (1) Area closure by wire fencing and guarding to prevent exploitation of the area during the rehabilitation phase until vegetation is sufficiently established (2-3 years). (2) Construction of millet stalk palisades arranged ideally in ‘checker-board’ squares, which act as windbreaks. These physical structures are a barrier to sand transport by wind, and thus are a prerequisite for revegetation. After two years the palisades fall apart and decompose - and the vegetation takes over the dune fixation function. Small erosion gullies can be controlled by check dams made from stone or millet stalks. (3) Natural regeneration, planting and seeding of annual and perennial plants (including Acacia spp. and Prosopis spp.) for soil stabilisation.

Establishment / maintenance activities and inputs: As soon as vegetation cover is established on the denuded surfaces the dunes can be used for grazing or for harvesting of herbs and fuelwood. Period and frequency of use should be determined in common agreement with all actors involved. In addition the pasture on the dune can be used as a ’reserve’ for late dry-season grazing, depending on vegetation development and herd size. Between 1991 and 1995, just over 250 ha of sand dunes were stabilised in the case study area. Incentives were provided by the ‘Projet de Développement Rural de Tahoua’ (PDRT, see also ‘Participatory land rehabilitation’ approach). After 1995 no further dunes were stabilised due to the high cost of the wire fencing, which local communities simply could not afford themselves. However, as the objective of the fence is to keep out humans and animals during critical periods (the rainy season), the same effect could be obtained at no financial cost through ‘social fencing’, that is agreement between stakeholders on where there should be no grazing. Furthermore the technology itself - which works well - could be relevant to situations where higher investment can be justified for specific reasons.

2.3 Photos of the Technology

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

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• through projects/ external interventions

3.1 Main purpose(s) of the Technology

• reduce, prevent, restore land degradation

• reduce loss of land

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

Comments:

Major land use problems (compiler’s opinion): The area suffers from an imbalance between availability of natural resources (constrained by soil fertility and rainfall) and the rapid growth of the human and livestock populations. As a result, there is chronic food insufficiency and an associated overexploitation of the natural resource base. Accelerated wind and water erosion further enhance the degradation of the soil resources. From the farmers’ perspective, the main problems are lack of grazing land, wood and drinking water (due to sinking water tables), insufficient and unevenly distributed rainfall. Sand dunes are fragile: when overexploited, they soon remain with only unpalatable plant species, eg Panicum turgidum. When the vegetation cover on dunes decreases even further, dunes start moving again, threatening fields, villages or depressions used for fruit and vegetable cropping.

3.3 Further information about land use

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

• rainfed

Specify:

Longest growing period in days: 90; Longest growing period from month to month: Jul - Sep

3.4 SLM group to which the Technology belongs

• area closure (stop use, support restoration)
• improved ground/ vegetation cover

3.5 Spread of the Technology

Comments:

Total area covered by the SLM Technology is 2 km2.

3.6 SLM measures comprising the Technology

3.7 Main types of land degradation addressed by the Technology

Comments:

Main causes of degradation: droughts (manque de pluie; pluie mal répartie), land tenure, faim

Secondary causes of degradation: soil management (pas de jachère; pas suffisamment d'intrants. Mulching, engrais, mat. organique), deforestation / removal of natural vegetation (incl. forest fires) (combustibles), over-exploitation of vegetation for domestic use, overgrazing, population pressure (croissance de la population), poverty / wealth (Manque de moyens financiers), labour availability, education, access to knowledge and support services

3.8 Prevention, reduction, or restoration of land degradation

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

• restore/ rehabilitate severely degraded land

4.1 Technical drawing of the Technology

4.2 Technical specifications/ explanations of technical drawing

Sand dunes in the process of stabilisation: millet stalk palisades hinder detachment and displacement of sand particles through wind, and help vegetative cover to re-establish. Fences exclude animals during the restoration process.

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: low

Main technical functions: improvement of ground cover, sediment retention / trapping, sediment harvesting, reduction in wind speed, stabilise sand dune surface, control detachment of particles by wind

Secondary technical functions: increase in organic matter

Agronomic measure: regenerated and seeded vegetation cover

Structural measure: millet stalk palisades

Structural measure: check dams (optional)

Change of land use practices / intensity level: area closure, controlled grazing

4.3 General information regarding the calculation of inputs and costs

Specify currency used for cost calculations:

• US Dollars

4.4 Establishment activities

	Activity	Type of measure	Timing
1.	Construction of wire fence around the dune	Structural	December to June
2.	Palisade construction, 2000 m/ha.	Structural	December to June
3.	Guarding the fenced area	Management	all year round

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	Enclose area and protect	ha	1.0	300.0	300.0	100.0
Equipment	Tools	ha	1.0	10.0	10.0
Plant material	Tree seedlings	ha	1.0	20.0	20.0
Construction material	Wire fence	ha	1.0	1120.0	1120.0
Total costs for establishment of the Technology					1450.0

Comments:

Duration of establishment phase: 36 month(s)

In the Sahelian zone of Niger, wind erosion constitutes one of the major causes of land degradation. Measures to combat wind erosion and sand encroachment were developed through a rural development project. However in this case the cost was too high to justify continuation: nevertheless the technology itself may be applicable in other situations

4.6 Maintenance/ recurrent activities

	Activity	Type of measure	Timing/ frequency
1.	Harvesting of millet stalks , 2,000 bundles/ha (1 bundle = 6-10 kg).	Agronomic	October to February / initial establishment
2.	Seeding of herbaceous plants	Agronomic	May, just before rainy season / initial establishment
3.	Transplanting of locally available trees reared in a tree nursery	Agronomic	June to July, early rainy season / initial establishment
4.	Replanting of dead tree/shrub seedlings (20% replanting).	Agronomic	June to July /
5.	Guarding the area closure	Management	all year round /
6.	Controlled grazing once the dune has been stabilised: for periods of between 1 day and a week every 2 to 3 weeks – as determined	Management	/ between 1 day and a week every 2 to 3 weeks

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	Maintain area and guarding	ha	1.0	45.0	45.0	100.0
Plant material	Tree seedlings	ha	1.0	5.0	5.0
Total costs for maintenance of the Technology					50.0

Comments:

Labour (per ha, for establishment) includes installing wire fence (16 person days), collecting and transporting millet stalks and installing palisades (175 person days), sowing of herbaceous plants (2 person days), planting tree/shrub species (6 person days). Seedlings: under PDRT the tree nursery was financed by the project and the plants delivered to the ‘village’ - planting was done by the local population.

5.1 Climate

5.2 Topography

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 fertility is low

Soil drainage / infiltration is good

5.6 Characteristics of land users applying the Technology

Indicate other relevant characteristics of the land users:

Off-farm income specification: due to out-migration of labour, commerce and also arts and crafts

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:

• communal/ village

Land use rights:

• open access (unorganized)

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Other socio-economic impacts

Socio-cultural impacts

Ecological impacts

Soil

Climate and disaster risk reduction

Other ecological impacts

6.2 Off-site impacts the Technology has shown

Comments regarding impact assessment:

Off-site benefits are difficult to assess and do not necessarily accrue to the local land users

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?

• 0-10%

Comments:

There is no trend towards spontaneous adoption of the Technology

Comments on adoption trend: There is no spontaneous adoption as the technology is too expensive, labour intensive, and implemented on communal land.

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
Technically it is feasible to prevent dune encroachment and hence reduce the danger it exerts on arable/pastoral land and villages How can they be sustained / enhanced? Prevent overexploitation, apply SWC measures that are technically and financially feasible (eg use cheaper fencing material or ‘social fencing’).
Decrease loss of arable/pastoral land How can they be sustained / enhanced? Prevent overexploitation.
Additional income to the land user How can they be sustained / enhanced? Planting multipurpose tree/shrub species on the protected dunes, encourage pasture management systems eg rotational grazing.

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

Weaknesses/ disadvantages/ risks in the compiler’s or other key resource person’s view	How can they be overcome?
Soil cover is very sensitive to overexploitation	In order to increase acceptance, involve the whole community in the planning and management processes of the stabilised dune.
Social conflicts between farmers and herders due to area closure	In order to increase acceptance, involve all actors, including pastoralists or their representatives, in the planning and management process of the stabilised dune.
Use materials for the palisades that do not have an alternative use as fodder (as millet stalks do) for example twigs of Leptadenia pyrotechnica). Plastic nets exist for making palisades, but these are very expensive. Labour requirements difficult to circumvent.	Initiate the establishment of sustainable management systems eg communally managed rotational grazing systems.
Area closure to prevent exploitation of stabilised dunes means restricted access to potential grazing areas	Involved actors can agree upon a local convention that prohibits access during rehabilitation – ‘social fencing’ – and restricted exploitation after this phase. PDRT started to plant Euphorbia balsamifera within the fence with the idea of eventually removing and using it on another site.
High costs for fencing