Demi-lunes or semi circular bunds are a simple to make and a multi purpose water harvesting technique in West Africa since 1980.
The concept was easy to understand and the farmers found it stimulating since it enabled them work in groups. A contour is first laid out with a water tube level then an A- frame swung around to mark a semi circle using tips on the contour. The crust is broken and soil dug out and manure added to fertilize the land.
Proper seeding
Grass seeds are then sown so that when it rains run off is captured and concentrated in demi-lunes then soaked into the soil providing ideal growing conditions for grass. The seedlings are natured by land users and are referred to as farmer managed natural regeneration. The major constraints farmers face is the availability of inorganic fertilizers for the demi- lunes.
More Biodiversity
Demi- lunes are versatile. They encourage germination and establishment of local tree species. They are also easy to construct and affordable. They can be used for crops, grass or trees and have become an effective sustainable water harvesting technology in Sahel region.
The water harvesting through demi- lunes helps restore biodiversity in areas where plants have been extinguished by drought which is very beneficial for both people and animals for food production.
