Farmers tackle desertification
Zimbabwe & Burkina Faso: Farmers tackle desertification and soil degradation with manure and zai pits
Each morning, Zimbabwean farmer Margaret Gauti Mpofu treks to her 5,000-square-metre plot in Hyde Park, about 20 kilometres west of the city of Bulawayo. She walks through the field, carrying a 20-litre plastic bucket filled with cow manure in one hand. With the other hand, she scoops out the manure and sprinkles a handful beside thriving leafy vegetable and onion plants, which she has sowed in rows across the length of the field.
Mrs. Mpofu is an urban farmer who is striving to protect her soil so she can harvest enough vegetables to feed her family and make an income.
The 54-year-old irrigates her field with treated waste water. She points to the narrow channels which floodwater has carved into the slopes of her field during irrigation. She says, “I shouldn’t be doing this…. The soil is losing fertility each time we irrigate because the water flows fast, taking valuable topsoil with it. I have to constantly add manure to improve fertility in the soil.”
Mrs. Mpofu feeds composted manure to her soil, but her efforts are small compared to the big problem of land degradation.
According to the United Nations Convention to Combat Desertification, known as UNCCD, more than half of agricultural land is affected by soil degradation. UNCCD says that 12 million hectares of arable land are lost to drought and desertification each year—enough land to grow 20 tonnes of grain.
Farmers contribute to desertification when they use unsustainable farming practices such as slash and burn methods of land clearing, poor irrigation, and overgrazing, which removes grass cover and erodes topsoil. Combined with climate change, desertification is reducing the amount of land available for agriculture.
Desertification has serious consequences for farmers in Africa, where two-thirds of arable land may be lost by 2030.
But it is possible to restore degraded land with improved agricultural practices. Burkina Faso is leading the way with both new and old practices, including farmer-managed natural regeneration and the traditional practice known as “zai pits.”
Yacouba Sawadogo lives in northwestern Burkina Faso. He explains that zai pits are holes that are dug into degraded soil and filled with compost. Farmers then plant seeds in the holes. During the rainy season, the holes capture water, and retain moisture and nutrients for plants during the dry season.
Farmers generally dig zai pits with a pickaxe, making the pits about 20 to 30 centimetres in diameter and 15 to 20 centimetres deep. They arrange the pits in staggered lines across a field or along the contour line of a hill, with up to 100 centimetres between pits. Farmers plant seeds in the holes after the soil has been well soaked by the first rains, and often fill add a few handfuls of manure once every two years. The seeds are sown around the walls of the hole, not in the middle.
Farmers can plant vegetables, maize, and other crops in zai pits. The pits also reduce water loss during irrigation.
Burkina Faso has severe soil erosion and dried-out soils due to a history of overgrazing and intensive farming. Yet, within 30 years, Mr. Sawadogo has used zai pits to transform a degraded area into a 15-hectare forest, which features several kinds of trees.