Zai pits are based on a traditional technology approach originating from West Africa that assists farmers working on marginal and degraded land. This approach involves the concentration and conservation of nutrients and water at the crop root systems through the digging of small pits (Zai pits) and filling them with compost, with the aim of increasing soil fertility and water infiltration. Zai pits are dug between planting season and filled with organic fertilisers/composts, which attract worms, termites and other insects, creating mix of material that can be used to fertilise crops. Farmers plant crops directly in these pits, prior to rains and water will infiltrate the pits more easily than the surrounding soil. Applying this technology is laborious to implement, but it has been found to assist farmers in times of drought or in arid conditions to produce successful crops by maximising the resources available. Zai pits allow for mitigation of desertification in degraded land and an economic use of resources in conditions of scarcity, especially in resource constrained environments
To effectively implement Zai Pits the following should be carried out:
- Step 1: Zai pits should be dug with a diameter of 30 cm to 40 cm and 10 cm to 15 cm deep.
- Step 2: Pits should be spaced 70 cm to 80 cm apart resulting in approximately 10,000 pits per hectare.
- Step 3: The farmer should place 2 – 3 handfuls (200 g to 600 g) of organic fertilisers or compost in each pit.
- Step 4: Holes that are dug between planting seasons will trap wind eroded soils, which are fertile and form good soils for plating crops.
- Step 5: It is recommended that 3 tonnes of fertiliser/compost per hectare be available.
- Step 6: Farmers should consider planting crops in these pits prior to periods of rain.
- Step 7: Repeated application of Zai pit technology on an annual basis will increase productivity of degraded land in the long term.
- CGIAR, 2014. Climate – smart soil water and nutrient management options in semiarid West Africa: a review of evidence and analysis of stone bund and zai techniques. Montpellier, France.
- The Food and Agriculture Organisation (FAO). 2016. Strengthening agricultural water efficiency and productivity on the African and global level. Rome, Italy.
- The Food and Agriculture Organisation (FAO), 2016. Farmers to Farmer Spread of Agroecology in the Eastern Region of Burkina Faso. Rome, Italy.
- The Food and Agriculture Organisation (FAO), 2018. The Climate – Smart Agriculture Training Manual. Rome. Italy.
- WOCAT, 2017. Zai or tassa planting pits. Niger.
Benefits
- Earth that is excavated from the hole dug can be used to form a ridge around each pit to help capture and retain water.
- Zai pit technology can be applied to marginal or degraded land or in semi-arid to arid conditions to allow farmers to rehabilitate soil/land and productively grow crops.
- Zai pits allow for nutrient concentration and water infiltration that provides improved conditions for crops to grow.
- Land that was previously degraded can become productive through the use of zai pits.
Drawbacks
- Implementing zai pits is laborious and takes significant people power to implement – but may be the only option in marginal environments.
