So much for old traditions being obsolete. The latest findings show that a soil building technique used in Africa for the past 700 years holds the promise of both mitigating climate change, and greatly improving crop fertility. Actually, it offers even bigger benefits than crop fertility, it will turn super poor soil into very rich ground.
What’s It All About?
You might think there’s nothing newsworthy in composting and charcoal, but there are only 2 known places in the world that have soils like this. One region is the Amazon in South America, where black soils created thousands of years ago by a culture long erased created a stir a few years ago. The problem is that we can only guess how at the soil building technique used to create it. Some experts think a large part of it’s super fertile construction is due to burial mounds or pottery dumps. What a great way to write off it’s importance, and make it seem like a feat not possible in today’s world. But it exists in over 100 locations in Sub Sahara Africa too, and the cultures who created it not only still exist, they continue enriching native soils the way their forefathers did up to 700 years ago.
A global team of researchers led by the University of Sussex were able to study exactly what goes into these super soil spaces, like black gold formations in a worn out plain. They found that although the soil building technique incorporates things we’re familiar with, there is a very distinct way these village farmers go about adding crop waste, kitchen slop (including bones), and charcoal into the soil. Nothing has been modernized, these villages follow the same traditions their ancestors have for centuries. And dark, incredibly fertile soil remains behind when the village moves on.
Photo: Victoria Frauisn via Australia Network News
A Soil Building Technique with More
In a paper published in the journal Frontiers in Ecology and Environment on March 1st, the team revealed the incredible properties of these ‘African Dark Soils’, which we can only assume are created with a similar soil building technique as those in the Amazon. But they are very similar, and nothing like any soil our knowledge has allowed us to build in modern times. It supersedes all other soils.
This ancient indigenous soil management system in Sub Sahara Africa employs targeted waste in a way that transforms highly-weathered, nutrient-poor, carbon-poor tropical soils into fertile, carbon-rich black soils. Their transformed state endures not just successive cropping, but centuries of time. Carbon dating places the pyrogenic carbon enriched soil found on top of the same native soil that surrounds these areas as between 115-692 years ago.
“What is most surprising is that in both Africa and in Amazonia, these two isolated indigenous communities living far apart in distance and time were able to achieve something that the modern-day agricultural management practices could not achieve until now.
“The discovery of this indigenous climate smart soil-management practice is extremely timely. This valuable strategy to improve soil fertility while also contributing to climate-change mitigation and adaptation in Africa could become an important component of the global climate-smart agricultural management strategy to achieve food security.” — Dr. Dawit Solomon, lead author from Cornell
200x More Carbon Storage
These newly created soils store 200-300% more organic carbon with 2-26 times greater pyrogenic carbon, which remains in soil far longer than all other forms of organic carbon. That makes it hugely important to long-term soil fertility and carbon sequestration.
pH Correction & Crop Nutrition Gains
The native soils in adjacent areas is strongly acidic (pH 4.3-5.3). But these African Darks Soils have the ideal crop pH (5.6-6.4) ideal for plant growth. They also retain 1.4-3.6 times higher crop nutrition and nutrient exchange capacity, and deliver 1.3-2.2 times more nitrogen availability, and 5-270 times more phosphorus.
As you might suspect, being the handiwork of small isolated villages, these black enriched soils exist in limited areas. Yet, they contribute a whopping 24% to total farm household income. The same soil provides the villagers with most of their food – reliably, in a challenging environment… one of those third world countries that Big Ag says it’s their job to feed. But the dark soils in Africa created with this soil building technique offer the world an alternative to conventional agriculture that is climate-smart, fully attainable regardless of financial means, corrects both worn out soil and those not suited to growing crops, and provides a means to food insecure populations for feeding themselves.
Out with the old and in with the new suddenly makes less sense. Especially when you see how deep this rich, black soil is in Liberia and Ghana. I’d share the photo, but it’s copyrighted to the journal. Check it out, and learn more details HERE.