Land degradation affects more than half of Africa, leading to a loss of an estimated US$42 billion in income and 5 million hectares of productive land each year. A precision-farming technique called “microdosing” is helping farmers address the problem of soil infertility.
The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), a member of CGIAR, has carried out research on land degradation in sub-Saharan Africa, where overuse of soil and low, unpredictable rainfall cause poor levels of food production. Given the risks involved with an unpredictable climate, farmers are not willing to invest in fertilizers to replenish the soil, and consequently soils are depleted, yields and crop quality decline, and hunger and under-nutrition are exacerbated. A vicious cycle is created: unproductive land is left and farmers clear forests to free up new land to plow.
Microdosing involves the application of small, affordable quantities of fertilizer onto the seed at planting time, or a few weeks after emergence. The microdosing technique increases the efficiency of fertilizer use, and helps improve productivity. The method uses about one-tenth of the amount typically used on wheat, and one-twentieth of the amount used on corn in the US. The small dosage needed illustrates just how depleted of nutrients African crops are.
The microdosing method has been introduced to Zimbabwe, Mozambique and South Africa, making fertilizer use a productive and economically viable option for the farmers.
However, there have been constraints to the technique, involving lack of access to fertilizer and credit, insufficient training and lack of supportive policies.
In eastern and southern Africa, ICRISAT is working with private fertilizer companies to identify appropriate fertilizer types and promote the sale of small packets suited to the resource constraints of small-scale farmers.
Working with its partners, ICRISAT hopes to increase the number of farmers using the microdosing technique from 25,000 to 500,000 in the next few years.
For more information on fertilizer microdosing, read the full case study from ICRISAT.