Biochar is a form of charcoal that has been used for centuries, but only in recent decades has its potential as a soil and livestock health improvement tool gained widespread attention.
Biochar is made through the pyrolysis of organic materials, and when applied to soil, it has been shown to improve fertility, increase crop yields, and enhance soil health. More recently, biochar has also garnered attention for its potential in improving livestock health and reducing environmental impacts from farming, such as ammonia emissions and methane production.
The Economic and Environmental Benefits of Biochar
The scientific community has been exploring biochar's role in agriculture for years, with over 30,000 publications on the subject. Research indicates that biochar can increase crop yields by 10-42%, improve phosphorus availability by up to 4.6 times, and reduce non-CO₂ greenhouse gas emissions by up to 50%. These benefits stem from biochar’s ability to enhance soil structure, improve nutrient retention, and promote beneficial microbial activity. Moreover, by sequestering carbon in the soil, biochar helps to mitigate climate change by preventing CO₂ from re-entering the atmosphere.
The International Biochar Initiative estimates that biochar production could help remove up to 6% of global emissions annually, contributing to global efforts to achieve net-zero emissions. While these results are promising, the uptake of biochar in commercial agriculture has been slower than expected. This is partly due to the significant variability in biochar quality, which depends on the feedstock used and the production process. As a result, farmers must carefully select biochar to match their specific needs, and there remains a lack of standardised policy or guidance to support widespread adoption.
Biochar Trials in Livestock and Soil Health
One of the key areas of interest is the use of biochar for improving livestock health and reducing environmental pollutants, such as ammonia and methane emissions. In recent trials, seven farmers explored biochar’s potential both as a soil additive and as an animal feed supplement. The goal was to assess whether biochar could improve livestock health, increase milk yield and quality, reduce ammonia emissions, and enhance soil health through better manure management and carbon sequestration.
Four of the participating farmers were biochar producers, all using the same kiln but different feedstocks. They supported small-scale farm production over commercial biochar products due to concerns about the variability in raw materials from large-scale producers. This hands-on approach allowed them to explore biochar’s benefits in real-world farming conditions, where waste utilisation and methane reduction are critical.
The trials involved three key phases:
Pilot Phase: Nine heifers were fed one bag of biochar every morning for seven days.
Extended Trial: Two groups of cows were compared, one fed biochar in addition to their normal diet and the other a control group with no biochar.
Pot Trial: The manure from both groups of cows was used in a greenhouse experiment to test its effects on soil health and crop growth.
Biochar’s Benefits in Livestock Feed
Adding biochar to livestock feed has been shown to have a range of benefits for animal health. Key findings include:
Reducing gas production from the rumen in cows, which can reduce methane emissions.
Increasing milk yield and quality, likely due to improved digestion and nutrient absorption.
Producing more stable manure, which can help reduce ammonia volatilization and improve nutrient recycling.
There are also potential benefits for manure management. Cattle fed biochar produce manure with enhanced properties for soil health. The biochar in the manure can help improve soil fertility, retain nutrients, and enhance microbial activity when used as a fertiliser or soil amendment.
Biochar’s stable structure means it is not broken down during digestion, so it passes through the animals' systems and into their manure, where it continues to offer benefits. This makes biochar a long-term solution not just for animal health, but also for soil regeneration.
Results from the Trials
The trials examined several important factors related to both livestock and soil health:
• Ammonia volatilisation from manure
• Manure ammonium levels, which affect soil nutrient availability
• Dry weight of crops grown using biochar-amended manure
• Worm burden in manure, as a measure of soil health and biodiversity
The pot trial, which used manure from biochar-fed cattle, showed promising results. When Italian ryegrass was grown using biochar-amended manure, the plants showed improved growth and higher dry weight compared to those grown with untreated manure. These results highlight the potential for biochar not only to enhance livestock health but also to improve crop yields when used as part of a sustainable farming system.
Conclusion
Biochar is increasingly recognised for its potential to improve agricultural practices in multiple ways. As a soil amendment, it enhances soil fertility, retains water, and sequesters carbon, helping to mitigate climate change. In livestock management, biochar improves digestion, reduces methane and ammonia emissions, and enhances manure quality, all of which contribute to more sustainable farming.
Although biochar is not a “silver bullet” solution, it has the potential to deliver both environmental and economic benefits when used thoughtfully. With growing interest from farmers, researchers, and policymakers, biochar is poised to become an essential part of sustainable agriculture, improving both the health of our soils and livestock while helping to address climate change.
References:
INTERNATIONAL SCHOL REPORTS: Biochar Use in Agriculture: The Economic and Environmental Benefits Written by:Luke Breedon NSch October 2024
INNOVATIVE FARMERS: Biochar for soil and livestock health
Commentaires