According to the UN, 12 million hectares of land - an area the size of Benin - are lost globally to desertification every year. "Continued land degradation is a threat to food security, leading to starvation among the most acutely affected communities and robbing the world of productive land," UN Secretary General Ban Ki-moon said at the launch of a decade-long effort to tackle desertification in August 2010. Meanwhile, an approach using livestock and specific grazing regimes has seen desertification reversed on over 2,500 hectares of degraded land, in Zimbabwe.
Overgrazing is often seen as a major cause of desertification. But by changing the way animals are managed, the Savory Institute (SI) and Africa Center for Holistic Management (ACHM) have restored 2,700 hectares of degraded land close to Victoria Falls by increasing livestock numbers by 400 per cent. Having increased land productivity, water availability and improved livelihoods, the approach is now being adopted by local communities and pastoralists in Namibia, Zambia, Kenya and Ethiopia.
A source of hope
The grazing approach*, an example of 'holistic management', mimics the natural movements of large herds of wild grazing animals. Livestock are grazed in one area for a maximum of three days, and are not returned for at least nine months. "Overgrazing is a function of time and not of animal numbers," explains Allan Savory, ACHM founder, former wildlife biologist, farmer and consultant. "Whether there is one cow or a thousand does not alter the fact of overgrazing but merely changes the number of plants overgrazed if the animals remain too long in the same place."
Moving across the land in large numbers, the animals break the soil crust with their hooves, trample litter to provide soil cover, and fertilise the soil with nutrient-rich dung and urine. This increases plant growth and improves soil quality. "What we are demonstrating is that we can return to formerly animal-maintained grasslands and savannahs to keep grasslands and their soils alive without burning billions of hectares annually to remove old dead grass in an attempt to keep such grasslands healthy," explains Savory.
"The effects are impressive," Savory enthuses. "We can barely keep pace with grass growth, even in dry years." Increased organic matter and improved soil structure also increase water infiltration and retention within the soil. "The river, which was dry most years, is now flowing again in all but the driest years," Savory observes. "We have water in pools with water lilies and fish through the dry season a kilometre above where they have been known before."
Spreading the word
Communities must work together and stick to the planned grazing regimes if the approach is to work, however. Mobilising whole communities has proved difficult in the past but, with funding from USAID, ACHM has been able to increase the capacity and skills of their staff. Target communities have now been selected to begin practising holistic management and the results, so far, are encouraging. "Even in one season, and doing the grazing badly, communities still got approximately four times the yield of grass," Savory explains.
Communities are also being taught how to use livestock to improve their crop yields. "Instead of transporting manure from the cow to the field, we encourage communities to bring their livestock together in the field for several nights before the crops are planted," explains Huggins Matanga, director of ACHM. Without ploughing, or any soil preparation, the farmers' yields are increasing by three-to-five times. "The difference is astronomical," says Matanga.
Designed as a learning site to demonstrate the impact of holistic management, ACHM's success has attracted governments, NGOs and pastoralists from all over Africa to learn more about the management techniques. Visiting pastoralists from northern Kenya have stated that holistic management is the only hope they see to saving their culture, livestock and livilihoods. Consequently, concerned Kenyans are now collaborating with SI and ACHM to establish a similar learning site to service the Horn of Africa.
A brown revolution
Soil degradation and burning grasslands release large amounts of carbon into the atmosphere, contributing greatly to climate change. "Without reversing desertification, climate change cannot be adequately addressed," Savory explains. "Livestock are vilified, but they are the only practical and readily available tool with which to reverse the degradation of the world's rangelands to address this aspect of global climate change."
Increasing soil organic matter by a mere 0.5 per cent on the 5 billion hectares of rangelands worldwide would sequester approximately 720 gigatonnes of carbon from the atmosphere, Savory states. In 2000, the total emissions globally were an estimated 44 gigatonnes. "Yet achieving an increase of two per cent organic matter would be reasonably easy if rangelands are managed holistically," he adds.
By storing large amounts of carbon, Savory believes that healthy soils offer the best hope of tackling climate change. "Biodiversity loss, climate change and desertification are the same issue," he says. "Anyone can grow more green plants using modern technology, genetic engineering and fertilizers, but this ignores the fact that the world is losing an estimated four tons of eroding soil each year per person alive today.
We need a 'brown revolution' that focuses on restoring healthy soils throughout crop and rangeland agriculture on which to both grow food and stabilise the climate. We have all the money in the world but we do not enjoy the luxury of time!"
-New Agriculturist
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