History of Biochar:
The importance of biochar in agriculture has recently been rediscovered, long before the discovery of the American continent by Christopher Columbus, the indigenous tribes of the Amazon region and especially the “Terra Perta” region used a technique to increase the fertility of their lands. It is certain that they had no knowledge of chemistry or biology and found this method with the help of trial and error. Their technique involved burning agricultural waste while covering it with soil, essentially burning plant debris under anaerobic conditions.
Experiments on these soils led to the conclusion that these soils are extremely fertile, and this combination has been able to significantly increase the quality and quantity of the product, and it has also caused the combined structure of the soil and water retention to improve greatly. An important point to be noted is that the soils of the Terra Perta region are still rich after centuries and have maintained their fertile quality.
The study and research on these soils has increased significantly in the last century due to the characteristics and benefits that follow in the short and long term; Between 2005 and 2012, more than a thousand scientific articles using the word “biochar” have been registered in the ISI database. Also, researches on this compound continue.
Production of Biochar:
Today, biochar is produced by the modernised process of “pyrolysis.” Pyrolysis is a Latin word that is composed of the combination of two words: “pyro” meaning fire, and “lysis” meaning separation.
The way this process works is that wood or agricultural waste is heated in a high-temperature furnace in conditions where oxygen is absent or found in an extremely small amount. The quantity of heat in the furnace and the length of heating directly affect the quality of the biochar that is produced.
What is created as a result of this process (pyrolysis) is a type of charcoal or active carbon called biochar. Due to its low decomposition rate compared to other organic materials, this material has a great capacity to reduce greenhouse gases such as carbon dioxide and methane released from agricultural waste, and it can store carbon for long periods.
Why Biochar:
Biochar can increase the efficiency of fertilisers and also reduce production costs and biological pollution. Biochar improves the soil and increases its fertility. This type of fertiliser increases agricultural products and can protect plants against some plant diseases. The useful life span of this rich material is one of the most important characteristics of biochar, both in terms of its impact and the stability of the structural quality of the soil in the long term.
Biochar has the potential for food recycling, soil conditioning, economic efficiency, the management of waste systems, and as a long-term agent for economical and reliable carbon sequestration. Research shows that the use of biochar in plants that need more potassium fertilisers and a higher pH can increase the yield.
Other beneficial effects of using biochar in agricultural soils include increasing organic matter, improving water retention in the soil, increasing cation exchange capacity, and interacting with the soil nutrient cycle by adjusting the soil pH and reducing the leaching of nutrients, as well as reducing the need for irrigation and the need for fertilizer. The high specific surface area and the structure of functional groups make biochar able to absorb and deactivate heavy soil elements.
From the point of view of agriculture, one of the advantages of biochar is the management of agricultural waste. The expansion of organic agriculture on the one hand and atmospheric pollution on the other hand have caused the use of this combination to increase day by day. The fertile terra preta soils in Brazil are the result of the use of biochar over thousands of years. In Japan, this technique (using half-burned agricultural waste) has been used and has been revived in the past few years. Other countries are gradually becoming interested in the use of this traditional and effective method, and the use of biochar will become a revived method from ancient times for agriculture in the future.
Help to fight climate change and environment:
The burning and decomposition of biological remains and organic compounds releases a large amount of carbon dioxide gas into the earth’s atmosphere. Biochar is stabilised carbon that can store a large amount of glasshouse gases for an extended period of time (a century or more) and thus control glasshouse gas levels. It has been concluded by scientific research that the application of moderate amounts of biochar can reduce nitrogen oxide (N2O) emissions by 80% and methane by 100%. Both gases are atmospheric pollutants and greenhouse gases.
Biochar can cause carbon sequestration in the soil for thousands of years. It is used to reduce the effects of global warming.
How much biochar you need for your garden?
For healthy soil, 5-10% biochar mixture is ideal. This is about a cubic foot for an eight-by-four-foot garden or a one-gallon bag for a four-by-two-foot garden. If the soil nutrients do not seem sufficient, you can adjust the mixture according to the soil’s needs. You can start with a 20% increase in the formula. However, if your soil is severely depleted of nutrients, start by increasing the ratio to half biochar and half compost.
Repeating this process over several months will gradually increase soil fertility, but keep in mind that it may take a few weeks to notice an improvement in plant growth as a result of increased nutrient absorption.
However, the added benefit of using biochar is that its porous composition helps retain water, so if your area receives little rainfall, biochar-enriched soil will help keep your garden better hydrated without the need to fill the soil completely. You will not have nutrients to preserve.