Burkina Faso is one of the poorest countries on the planet (176th country in the IMF list of the GDP per inhabitant with parity of purchasing power). The country possesses few natural resources and very limited industry. 80% of the population still lives on subsistence agriculture.
The population having doubled during these past 30 years, the Burkinabe agriculture is no longer able to satisfy the demands of the population. A depleted, infertile and stony soil, a hot and arid climate, as well as the lack of means to buy inputs and agricultural equipment, cause low and stagnant yields, far from the potential obtained in other regions in the tropics.
Finally, the Burkinabe producers, especially those in the province of Passoré (in the North region), suffer from the effects of climate change, which render the rains even more irregular and unpredictable (with recurrent pockets of drought), in a general context of feeble rainfall (500 to 600 mm per year, from June to September).
Fostering a strong degradation of the natural resources (water, plants, arable space, etc.), food and water insecurity increase from year to year.
In the region of Yako (Province of Passoré), where the Antenna Foundation is present with an agroecological didactic farm, the populations displaced by the conflicts in the North of the country find themselves in a particularly vulnerable situation. They only dispose of extremely degraded lands (compacted rocky earth, devoid of organic matter and vegetation) to cultivate their subsistence food.
Following the request of certain producers for the formulation of a strategy for the management and regeneration of these soils, the AgroEcology Unit of the Antenna Foundation, in collaboration with its partner the agronomist and hydro-pedologist Kalifa Zida, has elaborated the project « Soil and water regeneration ».
This pilot project consists in testing a regeneration strategy and enhancement of these degraded lands with 20 producers. The aim is to permit in the medium and long term a pedological regeneration and improvement of the water retention, all in guaranteeing a stable agricultural production in the short term.
The basic strategy firstly relies on practices already exercised by the producers in the region :
- Stone barriers : barrier of stones surrounding the plots to increase the retention of water and reduce the risks of erosion.
- Zaï holes : technique consisting of creating holes of 20 to 40 cm in depth and diameter, spaced from 30 to 70 cm, filled with manure and earth, where the plants are sowed (for example maize, sorghum, cowpea). The water will collect in these holes and its capture by the plant will be optimised.
- Half-moons : formation of basins of semi-circles in the form of half-moons, where manure is placed and the plants are sown. Water optimisation analogous to zaï holes.
Secondly, the strategy contains knew practices for the producers :
- Hedgerows : live fodder hedges of local species, adapted to the dry climate, are planted around plots of 1 hectare. The hedges serve to limit the run-off of water, as well as erosion, as much from water as from wind.
They also allow the creation of a micro-climate inside the plot, favouring the growth of plants. The hedges will also provide a fodder of quality for the animals, enabling the producers to enlarge their livestock and thus increase the production of manure, which improves the regeneration of the soil.
- Cultivation of brachiaria : brachiaria is a fodder grass adapted to the arid climate of the Sahel. It will be sowed around plots of 1 hectare, outside the hedges, as well as by way of a separation of 4 fields inside the hectare. The brachiaria fulfills the same functions as hedges, yet more quickly due to its rapid growth. It will also protect the young hedge plants from the attacks of stray animals. To crown it all, the brachiaria is a trap plant ; it attracts the cereals pests and kills them, thereby limiting the invasion of cereal crops.
- Cereal-stylosanthes association : this system is ideal for the regeneration of a degraded soil, while producing cereals. The important fixation of atmospheric nitrogen and the production of the biomass of stylosanthes, a legume, allows the creation of the manure necessary for the fertilisation and enrichment of the soil. The stylosanthes also limits erosion and protects the soil.
Finally, this association is ideal for ground cover and a fodder production in the dry season. The stylosanthes has the advantage of remaining green in the dry season and, if it is not overgrazed, it can cover the earth again and produce fodder all year round.
The Antenna Foundation provides, in addition to the technical support, a financial and logistical contribution to sustain the producers in the implementation of this strategy.
This contribution covers for each producer on a surface of 1 hectare :
- 400 young plants of fodder shrubs
- Digging a traditional water well to enable the irrigation of the young plants in the first years
- The seed of the brachiaria (500 g)
- The seed of the stylosanthes for 2 fields, being 5000 m2 (500 g)
- A couple of sheeps or goats to revive the herd of the producer
- A kit of tools : watering can, spade, shovel and pickaxe.
The principal objective is to test a strategy of regeneration of the degraded soils and optimisation of the water retention in the agroecosystems of Burkina Faso and to estimate its cost.
In the event of success of this pilot strategy for 20 target producers, a project of large-scale dissemination will be put in place.
The project should allow the water optimisation and the regeneration of the lands of the target producers, while guaranteeing them a stable and sustainable agricultural production. The latter will allow an improvement in the quality of life through the increase of the quality and quantity of the livestock in the short term and by the increase in the quality of the lands and the crops in the medium – long term.
This project will also enable the training of these producers in adequate agroecological practices and contribute to their dissemination.
The strategy in detail
- End May – beginning June : a stone barrier is built on the perimeter of the plot of 1 hectare.
- Early – mid-June : The brachiaria is sown on the exterior side of the barrier, in a way so as to separate the plot into 4 fields of 2’500 m2 each. The spacing is of 40 cm between the plants, with either one cutting or two seeds.
- Mid-June : the 4 fields are prepared with the usual traditional methods : zaï holes and half-moons.
- Two fields out of four are sown with a mixture of cereals-stylosanthes. The recommended spacing is of 1 m x 0.75 m between the zaï holes. Then, 2 lines of stylosanthes are sown between each line of cereals, with a space of 30 cm x 30 cm and 7 to 10 seeds in each seed hole. In the case of half-moons, the stylosanthes are sown between the half-moons with a spacing of 30 cm x 30 cm.
- July : young trees are planted on the interior side of the stone barrier, all around the plot of 1 hectare. One plants 1 tree each 1 m. The following species are planted : Gliricidia sepium, Sesbania sesban, Leucaena diversifolia, Neem, Moringa oleifera, Acacia, Prosopis, Boscia senegalensis, Combretum glutinosum.
These trees are watered in the first years thanks to the well.
In the long term :
The brachiaria, the stylosanthes and the leaves of the hedges are regularly trimmed to feed the animals. The latter, better fed, multiply and produce more manure, permetting the fertilisation and regeneration of the degraded soils. The stylosanthes and the brachiaria restructure and fertilise the soil directly in decomposing.
The combined different practices create a micro climate, increase the water retention in the managed ecosystem and limit erosion in protecting the earth.
The created well increases the availability of water and enables the survival of the hedge in the first years.
It can then permit a small irrigation in the case of need.