By Kayla Ruff

Source: Nature Design

According to a recently published study conducted in southern Niger, agricultural structures called ‘half-moons’ have the potential to substantially increase Niger’s crop productivity. Scientists assessed the effectiveness of these structures between 2013 and 2020 at 18 sites in southern Niger, and the results of the study revealed that there was a 25% increase in vegetative greenness at the intervention sites. As a nation with over 1.9 million people affected by severe food insecurity, land rehabilitation techniques such as half-moons could play a critical role in increasing crop productivity in Niger.

What are half-moons?

Half-moons are semicircular pits bordered with rocks, and they are constructed in large numbers throughout agricultural fields. These rock-bordered pits allow water to collect inside them, which reduces surface runoff and soil erosion. Half-moons are especially important in regions with erratic and unpredictable rainfall patterns. While rain from a downpour would typically roll off the soil, half-moons keep water in place, allowing it to seep into the soil and nourish crops.

How can land rehabilitation techniques restore Niger’s agricultural lands?

Niger is a hot and arid country, and unsustainable agricultural practices have made the nation’s dry lands even more susceptible to desertification. In fact, at least 100,000 hectares of agricultural land are lost each year in Niger. Increasing vegetative growth is vital for reducing the rate of land degradation, as it substantially reduces the impacts of soil erosion. Without vegetative growth, rainwater cannot penetrate beyond the surface, which degrades the land and causes more intense floods during the rainy season.

Local-scale land rehabilitation practices, however, could be the answer to restoring Niger’s depleted agricultural lands. The water-preserving capabilities of half-moons, for example, could play an important role in improving soil fertility in degraded ecosystems. The vegetation that grows as a result of these structures prevents erosion, thereby mitigating floods, which substantially increases crop yields.

Additional land rehabilitation techniques may be helpful in Niger

Aside from half-moon structures, many other local land rehabilitation techniques can help improve soil productivity and restore degraded lands in Niger. For example, a case study conducted in dry regions of Burkina Faso found that Zai pits rehabilitated degraded soils and reintroduced a large diversity of plants.Like half-moons, constructing Zai pits does not require advanced technology. Other agroecological interventions such as contour bunds, eyebrow terraces, and Negarim microcatchments also help restore vegetation in arid regions.

While all of these land rehabilitation techniques help improve agricultural productivity in barren areas, they require no advanced technology, making them simple and inexpensive to construct. Overall, implementing these sustainable and effective agricultural strategies will be critical to restoring Niger’s agricultural lands, which will, in turn, help reduce the nation’s food security shortages.

Zai Practice: A West African Traditional Rehabilitation System for Semiarid Degraded Lands, a Case Study in Burkina Faso: Arid Soil Research and Rehabilitation: Vol 13, No 4 (