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Best Practices on Indigenous Knowledge MOST/CIRAN


Improving tassa planting pits – using indigenous soil and water conservation techniques to rehabilitate degraded plateaus in the Tahoua region of Niger. (1)


Historically, most soil and water conservation (SWC) projects in Niger have been concentrated in the hilly areas of the Tahoua region (450 kilometers east of the capital, Niamey). This region is called the Ader Doutchi Maggia, and has densely populated pockets. Its fertile valleys alternate with badly degraded plateaus. In the past, the valley bottoms (fadama) were flooded regularly, and the floodwaters deposited fertile sediments each time. However, vegetation on the valley slopes is now badly degraded, which means that water rushes down the slopes and causes damage downstream. Large and small gullies have appeared on the slopes and in the valley floors, concentrating and speeding up the runoff. As a result, floodwater rarely spreads out slowly (e'pandage de crue), as it did in the past. Since the early 1960s, several SWC projects have intervened to treat valley slopes and/or plateaus. The most commonly used technique is the construction of contour earth bunds, which are often carpeted with stones to protect them from wind and heavy rainfall. The construction of contour earth bunds (fosse's ados) is often combined with subsoiling.

Until recently, most SWC projects carried out in this region completely ignored the techniques traditionally used by local farmers to rehabilitate barren, degraded plateaus (Haussa term: fako). This is surprising, since the rows of stones (gandari) are seen everywhere on the plateaus and are conspicuous throughout the entire area. The stones trap sand blown by the winds from the desert (harmattan) and conserve water. Farmers usually have to wait at least five years before enough sand has been deposited to permit cultivation. The traditional planting pits (tassa) can also be seen, but are not as prevalent in the area. They were used by some villages to rehabilitate degraded land. The pits were small; the excavated earth could be put anywhere alongside the pit, and no manure was used in them.

The SWC programme in Badaguichiri was funded by the International Fund for Agricultural Development (IFAD) and began in 1988. It limited its activities to the Illela district. The annual rainfall in this area varies greatly, but usually ranges between 250 and 600 mm. In 1989, the project organised a study trip for fifteen farmers, three of whom were women. The group visited the Yatenga region of Burkina Faso, where they learned two important lessons. The first was that farmers in the Yatenga perform SWC on their fields themselves, without a food-for-work arrangement, and the second was that the improved planting pits (zay) used widely and successfully in the Yatenga to rehabilitate degraded land, looked very much like their own traditional planting pits. Upon their return to the Illela district, some of the farmers improved their own tassa pits. They changed the size of the pits (diameter 25 - 40 cm., depth 15 - 30 cm., spacing 80 - 100 cm). They placed the excavated earth down slope to allow runoff water to collect in the pits, and they applied manure to the pits. In 1989, farmers treated three hectares with the improved type of tassa, and since then tassas have been quickly adapted by other farmers.


Region: Tahoua - Illela District


The programme builds upon indigenous techniques of soil and water conservation, like rows of stones and traditional planting pits to rehabilitate degraded plateaus.


Economic sustainability is achieved because:

  • no expensive equipment is needed, making the tassa very cost-effective.
  • the amount of useable land is increased.
Environmental sustainability is achieved by making badly degraded land productive.

Other: Farmers are treating degraded land owned by themselves. This reduces to a minimum the land tenure problems that often plague large-scale SWC projects that use heavy machinery. (see strengths and weaknesses)


The main stakeholders and beneficiaries are the farmers. Through1995, agricultural extensionalists were promoting the technique and providing the farmers with simple tools and training. Most farmers, however, were carrying out their own techniques without waiting for the extensionalists. Farmers learn and copy techniques from other farmers.

In the Illéla District alone, there are already thousands of farmers involved in the project.



  • simple
  • low-cost
  • low-maintenance
  • efficient because it increases yields quickly
  • attitude of donor agencies has to change towards these types of programmes
  • marketing of land may increase the social inequality at the village level, because it is likely that the poor will sell and the rich will buy.
  • use of inorganic fertilizers may not be economically feasible for farmers in dry years, because the extra gain will not always cover the costs of fertilizer. In years with more rain, however, it increases the yield very much.
  • Tassa are very cost-effective. On untreated land, yields are zero, but on land treated with tassa, yields in a year of good rainfall (1991) average between 500 and 600 kg./ha., and can reach as high as 800 to 1000 kg./ha. Even in years of low rainfall (1990, 1992), yields are perceptibly higher on rehabilitated fields than on untreated fields.
  • The region is characterised by considerable population pressure on limited agricultural resources. Farmers living on degraded plateaus, with no access to fertile land in the valleys, clearly have an interest in rehabilitating degraded land. The sandy soils they now cultivate are exhausted and infested with weeds (e.g., Striga).
  • Farmers are treating degraded land owned by themselves. This reduces to a minimum the land tenure problems that often plague large-scale SWC projects that use heavy machinery.
  • By treating their own fields, farmers improve food security for their families.

In 1993 - a dry year - the millet yield was 144 kg/ha without intervention. With the SWC technique and manure, the yield was 393 kg/ha. Adding fertilizer brought the yield to 659 kg/ha. (see remark under weakness).

In 1994 - a year with enough rain - the millet yield was 296 kg/ha without intervention. With the SWC technique and manure, the yield was 969 kg/ha. Adding fertilizer brought the yield to 1486 kg/ha.


With a few adaptations, the project could easily be transferred to other places, but two conditions must be met:

  • Well-adapted tools, such as pick axes, must be available.
This methodology has been replicated throughout the entire Illéla District, as well as in nearby districts and other parts of the country where soil conditions and population pressure on the land make it possible.


See note for information on the publication of ISWC phase I.

In 1998 the second phase has started. For more information take a look at http://www.vu.nl/Diensten/DOS/iswc2/folder.htm

1988 to 1995 (formal period, but the practice is still going on)


Chris Reij
Vrije Universiteit Amsterdam
E-mail: CP.Reij@dienst.vu.nl
(Address: see below)


Primary institute:

International Fund for Agricultural Develoment (IFAD)
Rome - Italy

Cooperating institutes:

Ministry of Agriculture
Vrije Universiteit Amsterdam
Centre for Development Cooperation Services
1081 HV Amsterdam
The Netherlands
Telephone: 020-4449090
Fax: 020-4449095
E-mail: cdcs@vu.nl
Url: http://www.vu.nl.cdcs


1. Information source: article by Chris Reij in:  The Indigenous Knowledge and Development Monitor, 1993, 1-1.
Fact material, i.e. on yield has been described by Abdou Hassane: Improved traditional planting pits in the Tahoua Department Niger. In: Sustaining the Soil - Indigenous Soil and Water Conservation in Africa, edited by Chris Reij, Ian Scoones and Camilla Toulmin, reprinted 1997, London: Earthscan Publications Limited
General information about the soil and water programme can be found at http://www.vu.nl/Diensten/DOS/iswc2/folder.htm

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