FARM meets Thibaut SOYEZ: preserving soil fertility in the Senegal River valley
In this 10th episode of FARM meets… Thibaut SOYEZ, an agricultural engineer and project manager at the FARM Foundation, presents the transformations affecting soil fertility in the Senegal River valley, one of the country's main rice-growing basins.
🎬 EPISODE 10: understanding soil depletion in the Senegal River valley
Before the construction of the dams in the late 1970s, fertility relied on three complementary practices:
- recession agriculture, which uses the moisture and silt deposits left by floods; ;
- fallow land, periods when the land is left to rest in order to regenerate; ;
- common pasture, where herds, moving according to the seasons, naturally enrich the soils with their droppings.
The construction of dams and the development of irrigation have led to increased yields, particularly through double annual rice cultivation… but have also profoundly altered this traditional balance: floods have become less regular, fallow land has been reduced, and the passage of livestock has been limited.
In irrigated areas, prolonged soil saturation with water leads to hydromorphism (waterlogged soil that suffocates the roots), while insufficient drainage promotes salinization, which is harmful to rice. These changes weaken the chemical, physical, and biological components of fertility. Faced with these challenges, producers are using several strategies to restore life to the soils :
- input of organic matter, essential for replenishing nutrient stores; ;
- drainage, to limit salinity; ;
- salt-resistant rice varieties, results from research; ;
- recycling of crop residues, to maintain a fertility cycle.
Practices that combine traditional knowledge and innovations, in order to preserve a strategic territory for Senegal's food security.
The FARM Foundation warmly thanks Thibaut SOYEZ for the precision and pedagogy of his analysis, as well as all those who follow and support our work.
👉 Find all our actions on soil fertility in West Africa: https://fondation-farm.org/projet/renouveler-la-fertilite-des-sols-en-afrique-de-louest/
