What is Biochar? The Soil Solution that Benefits Farmers and Climate
TechnoServe's Floor Overbeeke reports from Kenya on biochar, a promising environmental solution that benefits smallholder farmers
On a recent project visit in Kenya, I saw a great win-win solution in action: biochar.
Every year, farmers in the developing world burn more than 10 billion tons of crop waste in their fields. The combined annual CO2 and CO2-equivalent emissions from crop waste burning are equal to the annual emissions of 714 coal-fired power plants.
The alternative – converting the waste into biochar instead of burning it – removes three tons of CO2 from the atmosphere for every ton produced. When added to fields as a soil amendment, that carbon is permanently sequestered.
The long-term benefit of making biochar is a huge reduction of greenhouse gases that contribute to global warming.
Biochar Benefits for Climate and Farmers
Last week, I visited a TechnoServe project on the Kenyan coast where we are looking at how to create win-win solutions for smallholder farmers AND the climate, through the transformation of large quantities of organic waste into products that are of value to smallholder farmers.
Biochar is a super charcoal made by heating any biomass – for example, coconut husks – without oxygen. All of the non-carbon materials gasify and are burned away. What remains is pure carbon – 40% of the carbon originally contained in the biomass.
Many studies in different regions around the world, but especially in places with degraded soils, have found positive outcomes for smallholder farmers:
- Higher yields
- Healthier, lower-acidity soil
- Better water retention in soil
- Stronger plants
- Richer soil life
- Less contamination
- Higher fertility
- Promotion of seed germination
It especially tends to improve nutrient retention in sandy soils like the ones at the Kenyan coast.
In addition, using coconut husks to produce charcoal briquettes could help offset fuel wood demand and reduce deforestation and forest degradation.
Testing the Best Win-Win Solutions
We’ve set up different systems to produce biochar from coconut husks and are testing the effects of biochar on soil moisture, soil nutrient retention, yields as well as reducing carbon emissions.
To better understand the value of the biochar and the quantity that farmers can absorb, we’re doing extensive field trials to get an in-depth understanding of its agronomic value and determine the optimal application amount for smallholder farmers.
Stay tuned for the outcomes of our study to learn more about how biochar can improve both farmers’ incomes and the environment.
