Moving from the wet, rice-producing regions of Madagascar to the dry sub-Saharan African mainland, today’s post discusses a range of options available to tackle land degradation and maintain long-term soil fertility. World Resources Institute’s annual World Resources Report is focused this year on ‘Creating a Sustainable Food Future.’ A fourth installment on farmer innovation for land and water management launched last Wednesday on World Food Day. It introduces examples of farmer-driven innovations in Malawi, Burkina Faso, and Niger that are improving the sustainability of on-farm practices, but the paper also argues this is not enough. These practices must reach across a broader scale to have real impact, and an integrated landscape approach can play a vital role in coordinating these practices and reaching this scale (see p.22 of paper). We share an excerpt from the WRI Blog story by Robert Winterbottom and Chris Reij.
Sub-Saharan African farmers have been fighting drought and land degradation for years. In response, a growing number are starting to adopt improved land and water management practices to reduce erosion, capture more rainfall, increase soil organic matter, and replenish nutrients. Their encouraging results provide lessons in the types of strategies needed to restore the productivity of cropland and produce enough food for a growing population. Improved land and water management practices such as agroforestry, conservation agriculture, rainwater harvesting, and integrated soil fertility management are sustainably increasing crop yields while also reducing agriculture’s impact on the environment.
- Farmers in Burkina Faso and Niger are using water-harvesting techniques such as building stone lines and improved planting pits (locally known as zai). These practices help to trap rainfall on crop fields, increasing average cereal yields from 400 to 900 kilograms per hectare (kg/ha) or more. Applying small quantities of fertilizer directly to seeded crops or young shoots early in the rainy season can complement these low-tech land and water management techniques. Combining this “micro-dosing” with practices like water-harvesting has increased millet and sorghum yields from fewer than 500 kg/ha to 1,000 or 1,500 kg/ha.
- Farmers in Malawi are planting Faidherbia albidatrees on fields using modest amounts of fertilizer. These trees provide canopies of shade and lock nitrogen in the soil. Farmers have seen their maize crop yields increase from fewer than 2 tons per hectare to 3 and 4 tons per hectare. Yields are more than 7 tons per hectare when these conservation agriculture practices are combined with agroforestry, fertilization, and other strategies.
- In West Africa, farmers are employing integrated soil fertility management by applying crop resides, compost, mulch, livestock manure, leaves, and fertilizer. These practices help farmers meet the nutrient needs of the crop while restoring soil organic matter and overall soil fertility, which contributes to sustainable intensification of crop production. Integrated soil fertility management across more than 200,000 hectares resulted in crop yield increases of 33-58 percent over a four-year period. Farmers also saw revenue increases of 179 percent from maize and 50 percent from cassava and cowpea.
WRI’s fourth installment of the World Resources Report recommends seven approaches to accelerate the scaling up of proven, cost-effective land and water management practices. Download the full paper.
Photo credit: Erin Gray (WRI)