Incredible properties!
The porous structure of the carbonized residue of just 1 g of biochar provides an incredible total surface area of 1000 to 2500 m2 to very effectively trap nutrients, retain water and promote the maintenance of microorganisms essential to living soil.
-> Consult the application guide.
Pre-Columbian Amazonian societies used to dispose of their waste by burning it under a layer of earth. Without air, bones, fish bones, plant waste, excrement, pottery debris and others were slowly transformed through pyrolysis into a black substrate that these communities incorporated into their agricultural soils.
called black earth (black earth) by Portuguese explorers, this carbon-rich soil amendment is today called biochar.
Dutch scientist Wim Sombroek is credited with bringing to the world's attention the immense potential of black earth discovered during research in the Amazon in the 1950s. His book Amazon Soils published in 1966 was the starting point for research into what is today called biochar.
The rainforest paradox
Although biomass production abounds in the tropics, its decomposition is so rapid that organic matter disappears in no time:
- Cleared land quickly loses its fertility when the supply of decaying vegetation is interrupted; And
- Heavy rains contribute to depleting the soil by leaching nutrients.
The addition of black earth in the less fertile cultivated lands of the Amazon corrected this problem in a sustainable way. Indeed, it was observed that the level of fertility of soils containing this black earth had been maintained in some cases for more than 500 years!
La black earth still exists in approximately 10% of the soils of the Amazon basin. Although this agricultural technique dates back more than 2500 years, contemporary agronomists have only recently discovered its immense potential for modern agriculture.
Like everywhere else in the world, Amazonian populations have grouped into large cities around flourishing agricultural areas. Unfortunately, the arrival of Europeans in the Amazon sounded the death knell for these ancient metropolises by introducing smallpox. By decimating 90 to 99% of the inhabitants of these imposing cities, the terrible disease wiped them out.
Why carbon?
Yes why ?
After all, this element is not part of the trio of NPK nutrients that farmers think of when looking to improve the yield of their land. And we don’t sell carbon in garden centers for plant care!
The reason, however, is simple: carbon is not a direct fertilizer like all these classic nutrients.
However, more and more gardeners and farmers are realizing that adding direct fertilizers exclusively is a short-sighted practice. Like our ancestors, we must consider soil fertility in its entirety, paying attention to the balance of the ecosystems involved.
The porous structure of the carbonized residue of just 1 g of biochar provides an incredible total surface area of 1000 to 2500 m2 for :
- trap nutrients very effectively;
- retain water;
- promote the maintenance of microorganisms essential to living soil.
In addition, thanks to its negative charge, carbon attracts positive ions like calcium and potassium. In doing so, it reduces soil acidity caused by the constant addition of nitrogen fertilizers to improve productivity.
ABC of biochar
The pyrolysis process which makes it possible to produce biochar is simple:
- Slow cooking with almost no oxygen.
For commercial biochar production, the gasification method is the most popular due to its efficiency in almost completely carbonizing the biomass. Wood chips, peanut shells, rice straw and other residues are used depending on the availability of the material.
Under the effect of intense heat, the combustion of gases and oils which separate from the solids can be used to produce energy, or even to fuel pyrolysis! Biochar represents the carbon-rich solids that result from this slow but intense cooking.
- The slower the combustion, the higher the proportion of biochar obtained.
The adaptability of the pyrolysis process makes biochar production accessible to everyone, from small independent growers to large commercial companies.
The choice of biomass depends greatly on its availability. The idea is not to produce biomass or raze the forest to make biochar, but to revalorize our numerous forest, agricultural and urban waste.
Search to establish the difference between the properties of biochar depending on the nature of the biomass used to produce it is underway. In the years to come, we will certainly see biochar from various sources sold in bags in garden centers, as is currently done for compost!
More than just an amendment
Biochar represents a future solution for sustainably improving the yield of agricultural land, in addition to being an excellent way to sequester carbon in the soil.
It is estimated that the production of biochar would capture billions of tonnes of carbon dioxide each year. It would also eliminate all greenhouse gas emissions associated with the decomposition of organic waste by transforming it into biochar.
Thanks to its extraordinary properties, scientists suggest that biochar is the missing link (found!) of living soils and even an unexpected ally in the fight against climate change.
