[ad_1]
Is Africa’s soil developing an unstoppable malady that will transform our continent from an innocent victim of climate change to its main driver?
The answer would appear to be yes. Because we may be sitting on a ticking carbon bomb. Soil degradation in Africa is accelerating, costing us millions of hectares of land every year. Although scientists have long known that soils “exhale” pure carbon dioxide, worryingly our hot, arid soils are now exhaling more, perhaps a lot more.
This is a source of carbon that is almost negligible compared to the greenhouse gases produced by humans. Worryingly, it could make Africa the largest carbon emitter.
But no one knows for sure. Researchers have found, over a decade or more, that organic carbon in soil (such as plant roots) Degradation is faster in warmer post-drought soils—and other studies have found that this is not the case. They are counting deep soil carbon, soil carbon after late rains, soil carbon near volcanoes, soil carbon after soils have dried out for four years, and soil carbon beneath forests: in a range of carbon measurements, trying to map the changes.
Ominously, amid all the “we’re now looking at soil carbon” noise, the constant alarm, and even the occasional famous public fight between scientists, it turns out that our carbon calculations have never included soil respiration.
There is more carbon in the soil of this planet than in the atmosphere and all vegetation combined, and most of it is soil organic carbon, which releases carbon dioxide.
This is a missing sum, and the acceleration of climate change only makes the situation more worrying. We shouldn’t be experiencing 50°C temperatures for the first time, the hottest year on record, the wettest and driest seasons with each new season: all this is happening faster than the graphs show.
Until soil factors are taken into account.
This makes soil a geopolitical focus for discussion at summits held by presidents of various countries.
This also brings Dr. Cary Fowler, the current U.S. Special Envoy for Food Security, into the fight, his second effort to lead the world away from destruction.
Dr. Fowler created the Svalbard Seed Vault to preserve global diversity. Now, his mission is soil, and he’s not waiting for the science to be perfected.
“I’m not a soil scientist, but we are deeply concerned about African soils,” he said during a visit to Nairobi this year for the African Soil Summit.
Yet his solution is a good thing for Africa, just as his seed bank is for biodiversity – how do you stop the rapid degradation of soils on the continent?
It took decades to stop energy emissions from growing. So where do we start to break the cycle of rising temperatures and erratic rainfall that leads to land degradation? Degraded land cannot support carbon uptake by ground cover, while emitting more carbon, leading to further heat and weather disruptions.
A potentially prescient starting point is France’s call at the 2015 Conference of Parties for a global commitment to increase soil organic carbon levels by 4 parts per thousand — in order to give the world an extra 20 years to tackle greenhouse gases.
This has sparked a strong interest in “regenerative agriculture”.
However, Africa already has the lowest soil organic carbon content in the world and is continuing to decline, and African farmers and countries have very limited incentives to improve land management.
Despite the proliferation of initiatives to entice farmers to adopt new methods to boost soil carbon, Verra, the world’s leading verifier of carbon credits, has observed with dismay that these measures often reduce farmers’ yields for a while — bad news for a continent already struggling with a booming population and falling yields.
So Dr. Fowler started over, looking for a win-win solution.
Working with the FAO, the Rockefeller Foundation and what he excitedly concluded were the best scientists in the world – in subjects ranging from soils to agronomy and nutrition – he promoted a project called VACS, which aimed to find plants that could solve all the problems. He claimed to have found them.
“We look at plants differently now,” he explains. “We always thought of plants and soil as separate things, but now we look at them as a single system.” This single-system orientation has enabled his VACS team to select 60 crops that can grow in Africa’s degraded soils and unstable climates; that improve the soil in the process, creating a better future and restoring the land; and that provide excellent nutrition.
Nutrition is also important on the continent, as micronutrient deficiencies can lead to child and maternal mortality, brain damage, and a host of lifestyle diseases from diabetes to high blood pressure.
The savior crops turn out to be indigenous—although not intentionally so. Millet, sorghum, yams, amaranth, Bambara groundnut, pigeon pea and sweet potato, to name a few. But growing them works: it boosts yields, curbs land degradation and tackles diabetes.
Many African farmers have commented that they have always been users of crops and we shouldn’t change that, but in their historical form they didn’t carry the huge, vital label that their deep roots pull carbon from the air and into the soil, and also slow down all kinds of soil degradation.
This is even more important today, creating a path to saving the world by growing the crops we grew in the past, thereby addressing massive food insecurity, putting marginal land to good use, and reducing our carbon footprint.
So thank you, Dr. Fowler. I hope you can save our soil.
Jenny Luesby is a food systems consultant specialising in climate change and publisher of the farmer information service FarmBizAfrica.com
Follow and subscribe to Nyasa TV:
[ad_2]
Source link
