Biochar is a relatively new term, but the idea of using it in gardens is not new. Researchers believe early Amazon rainforest residents used biochar to increase soil productivity. They made it by slowly burning agricultural waste in pits or trenches. It was common for Amazonian farmers to grow fruit trees, corn, and melons in soil enriched with compost, mulch, and biochar.
Biochar is an environmentally friendly method of fertilizing. Its primary benefits include reducing climate change by removing carbon dioxide from the atmosphere. It can also be used to make oil and gas by-products, which are clean, renewable fuels. Continue reading to find out more about BIOCHAR.
Biochar amends soil, following a process that began thousands of years ago in the Amazon Basin. There, rich and fertile soils were called Terra preta (dark Earth) by native people. According to anthropologists, soils rich in fertility and high carbon content were created by deliberately adding charcoal and cooking debris. These soils are still “holding” carbon and are so rich in nutrients that they can be dug up and used as potting soil in Brazilian markets.
What is Biochar?
Biochar is a fine-grained form of charcoal made by slow-burning wood and agricultural by-products at low temperatures with reduced oxygen. It is valuable in areas with limited water resources and severely depleted soil.
Biochar is made by heating biomass in an indirect-fired, high-temperature rotary kiln. This process is referred to as torrefaction. However, torrefaction usually refers to pyrolysis and wood biomass.
Any form of biomass can be used to create biochar, including animal byproducts and agricultural wastes. The characteristics of the final product will depend on the source material and the variables involved in the pyrolysis process.
Biochar is an ancient concept that originated in Amazonian civilizations thousands of years ago. In these instances, charcoal was mixed with cooking debris to create Terra preta soils, which are dark, fertile, and nutrient-rich.
Biochar and Environment Biochar is the best method of disposing of waste. It is the only way to prevent the release of greenhouse gases into the air. The resulting product also sequesters atmospheric carbon for many years. Biochar can be used in gardens to support a new technology that has the potential for a significant impact on Mother Earth. The product is manufactured at extremely high temperatures, so it doesn’t contain PAHs (Polycyclic Aromatic Hydrocarbons) and PCBs (Polychlorinated Biphenyl). These compounds are not required to be tested for organic certification.
Biochar As Soil Amendment
Biochar’s porous surface and chemical properties allow it to capture small particles and keep them there. This allows biochar to attract and hold nutrients, moisture, and other agrochemicals. It also provides a home for microorganisms. Biochar is also less susceptible to decay and can last longer in soil than other organic matter types (terra preta soils have lasted for thousands of years), making its effects long-lasting.
The unique structure of Biochar gives it its benefits. It is a good carbon source, but it can take thousands of years to break down completely. It can increase organic matter content by providing a better soil environment for organic matter to grow.
Biochar’s porous structure offers the following benefits:
- It attracts and holds water molecules, improving the soil’s water retention capacity. This is particularly useful for soils with poor water retention and areas with low rainfall.
- Biochar is a material with a negative charge. It binds nutrients like calcium, potassium, and magnesium. This results in lower soil acidity (a higher pH).
- Because of the nutrient binding, less fertilizer is required. It is safer for groundwater as well as surface water because there is less runoff.
- It reduces nutrient leaching and increases Cation Exchange Capacity (CEC), making nutrients easier for plants to absorb.
According to the International Biochar initiative, biochar may offer the following benefits for soil:
- Improved water retention
- Moderation of soil pH
- Reduction in nitrogen runoff
- Increased numbers of beneficial soil microbes
- Possible reductions in nitrous oxide emissions
- Increased cation-exchange capability can improve soil fertility
Biochars are not the same, and soils react differently to them. Although more research is required on this topic, many believe that biochar as a powerful catalyst for improving soil fertility and crop yield could also play a crucial role in meeting the food security needs of an ever-growing population. It increases soil fertility, crop yields, and nutrition even in difficult areas with limited water availability or soil depletion.
Biochar Use in Gardens
Biochar is a soil amendment that enhances plant growth. Biochar makes the soil more beneficial for plants because it makes nutrients available in more significant quantities. It also reduces the need for fertilizer and water. Because more nutrients and moisture remain in the soil, they don’t leach into groundwater. Biochar, which retains essential nutrients like magnesium, calcium, and phosphorus, is believed to make the soil more efficient.
How to Make Biochar?
Biochar can be made in your garden by burning wood shavings, weeds, and other garden debris. Light a fire and let it burn down to reduce oxygen levels quickly. The smoke should initially be white from water vapor being released. As resins and other materials are burnt, they will turn yellow. Cover the fire with approximately one inch (22.5 cm) of the newspaper when the smoke becomes thinned and grayish-blue in color. Use excavated soil from your garden. Let the material smoke for a while until it forms chunks of charcoal. Then, water the fire with water.
You can use biochar fertilizer by incorporating the pieces into your soil or adding them to your compost pile. Charcoal briquettes made from barbecue charcoal may look like a great source of biochar; however, they can contain solvents and paraffin, which could be dangerous for your garden.
Charging Biochar Before Planting
To reach the root zone, aim for a layer of biochar up to one inch thick. Mix it to a depth of at most six inches. Adding it more than once is unnecessary as it will last a lifetime.
Mixing your biochar into your compost pile is the best way to activate it. You can add biochar to your garden in any amount you need, but not more than the compost. This improves the effects of biochar when added to the soil, makes composting faster and more productive, reduces gaseous emissions, and has a lower odor.
You can double-charge biochar using soiled bedding from farm animals in your compost piles. It will activate well once it has been spent. You can also activate biochar by adding it to your compost tea. Simply stir the biochar into the water and brew according to the instructions.
Benefits of Biochar
Biochar is the soil’s best friend. Because of its chemical and physical nature, biochar has the unique ability to attract and hold moisture, nutrients, and agrochemicals. It can even retain difficult-to-hold nutrients such as nitrogen and phosphorus. Regular soils tend to have high nitrogen levels, which can cause problems for streams and riparian ecosystems. Biochar can also hold gases. Various researches have shown that biochar-enriched soils reduce CO2 and N2O by 50-80%. N2O, which is 310 times more powerful than CO2, is a significant greenhouse gas.
Add biochar to the soil to improve crop yields and plant growth. This is especially useful in areas with limited soil resources, low organic materials, and insufficient access to agrochemical fertilizers and water. Biochar is not compatible with all soils, and results may take up to one year.
Biochar’s impressive surface area and complex pores (a single gram can cover more than 1000 square yards) provide a safe environment for microorganisms. Certain fungi are closely related to plant roots fibers, allowing for increased nutrient uptake. These fungi could be responsible for Terra preta’s ability to regenerate.
Biochar’s persistence in soil. There is no doubt that biochar is more durable than any other organic matter applied to the soil. It is more durable than common fertilizers because it can be stored in the soil for extended periods (more than 2500 years). Biochar is comparatively inert and doesn’t react to chemical or microbial degradation. It can even be buried.
Biochar can reduce soil acidity and liming requirements, but it does not add nutrients. It is made from manure; however, it is an exception. It retains significant amounts of nutrients from its source. Biochar retains soil nutrients and attracts them, something common organic matter can’t do. Thus, biochar reduces fertilizer costs and retains fertilizer for a longer time. This indirectly benefits climate change because it reduces the need for fertilizer.
Recent research at the American Chemical Society annual meeting showed that biochar combined with chemical fertilizer results in a 25-50% increase in winter wheat growth compared to chemical fertilization alone. Soil Science Society of America research found that biochar with fertilizer supplemented outperformed fertilizer by 60%.
Advantages of Biochar
Biochar offers many benefits because of its properties.
- Better Water Retention: Biochar is a moderate porosity that improves soil’s capacity to retain water. It also aids soil growth by assisting vegetables and plants.
- Reduced Soil Acidity: One of the primary advantages of biochar is that it aids in reducing soil acidity, which can hinder crop growth.
- Carbon Sequestration: The process of converting biomass into biochar can produce carbon dioxide in the air, but it is not as much as burning biomass. Biochar is a carbon sink in soil.
- Agriculture Production: Applying biochar to the soil improves agricultural productivity and resilience.
- Lower Emission of Greenhouse Gases: Biochar is a solid product that can be kept in soil for several years, eventually reducing the emissions of greenhouse gases resulting due to the burning of biomass.
Disadvantages of Biochar
While there are numerous benefits of biochar use on soils, it also has a few disadvantages.
- Soil Compaction: The regular application of biochar results in soil compaction that reduces crop yield.
- Impacts Crop Yield: Biochar does increase agriculture’s production; however, it takes up nutrients, causing a deficiency in nutrients that plants need to grow.
- Soil Degradation: Biochar’s use can result in soil degradation and make soils more vulnerable to extreme climates.
- Limit the Activity of Worms: Due to biochar use in soils, worms’ activity decreases, which is vital for the soil’s productivity.
- Lowers effectiveness of Pesticides: Biochar can also impact how pesticides are applied, thus decreasing the efficacy of pesticides on the soil.
Biochar can be used for a range of purposes that enhance the soil’s structure and boost agricultural production. It gives moisture to the soil and could be thought of as a solution for soil infertility caused by changes in the climate.