The effects of climate change are already being felt across the globe. Scientists estimate that we would need to remove 200 billion tons of carbon dioxide from the atmosphere in order to stop and begin reversing the effects of climate change. But removing that much carbon from the atmosphere would require a multi-faceted approach and global cooperation. Carbon farming may be one major piece of the puzzle.
Agriculture is one of the biggest contributors to global carbon emissions. In fact, agriculture and forestry account for at least a quarter of the world’s carbon emissions and 9% of the U.S.’s carbon emissions.
While current practices may be contributing to environmental harm, agriculture is one industry that is uniquely positioned to transform itself into a carbon sink. How? Through the process of carbon farming.
What is Carbon Farming?
Simply put, carbon farming is the process of removing carbon dioxide from the atmosphere, and storing it in soil, plant matter and microorganisms.
Many of the practices for carbon farming are common in hot farming practices, including permaculture, regenerative agriculture, organic farming and other alternative approaches to food production.
During the process of photosynthesis, plants remove and store carbon dioxide from the atmosphere. When the plant dies, that carbon is either released back into the atmosphere, or it gets stored in the soil for long periods of time.
With conventional agriculture practices, that carbon is usually released back into the atmosphere. Practices that fall under carbon farming do the exact opposite.
There are at least 32 Natural Resource Conservation Service (NCRS) conservation practices that help with soil carbon sequestration and improve soil health while increasing biodiversity, water retention, hydrological function and resilience.
How is Carbon Stored in Soil?
Every living thing on this planet is made of carbon. When living organisms breathe out, they release carbon dioxide into the air. That carbon dioxide is removed from the atmosphere through the process of photosynthesis. Photosynthesis is what helps plants grow.
In order for carbon dioxide to turn into soil carbon, it must be captured by plants during the photosynthesis process.
As plants grow, they produce new shoots, leaves and roots. But at the end of the season, those leaves fall to the ground where they turn into organic matter in the soil. The dead matter becomes food for microbes, which release carbon dioxide back into the atmosphere. Carbon can also be released back into the atmosphere when soil or plant matter burns.
There are two types of soil carbon: biomass and non-biomass. Biomass carbon includes living fungi and bacteria, while non-biomass carbon includes starch, cellulose and lignin from dead plant matter. Some of these will bind soil particles together in the soil structure itself.
Perennial grasses are a great example of this. These plants periodically shed their roots into their soil. The dead roots feed soil foodwebs.
The Carbon Cycle
Carbon cycles through five pools on the planet. It starts with the sun, which is the fuel for the carbon cycle. This cycle moves carbon through the atmosphere, pedosphere, biosphere and oceans.
But human activity has thrown everything out of balance. Sequestered fossil carbon is extracted and used as fossil fuels. When burned, they release a massive amount of carbon dioxide and energy. We’ve reached a point where there is more carbon dioxide being released into the atmosphere than the earth’s plant life and oceans can reabsorb.
The excess carbon has created a blanket in the atmosphere, which has trapped the sun’s heat and is rapidly changing our climate. Carbon farming can help the atmosphere move towards a more balanced state.
It’s not a cure-all solution, but it can go a long way in removing carbon dioxide from the atmosphere.
Carbon Farming Planning & Practice
Carbon farming planning should start with an assessment of the farm’s potential for carbon sequestration and greenhouse gas reduction. Other issues should also be addressed, such as surface and ground water degradation.
Some common carbon farming practices include:
- Converting manure and organic waste into compost to eliminate methane and air quality issues.
- Composting to improve soil health as well as water retention.
- Returning leftover biomass to the soil as mulch instead of burning or removing it.
- Replacing conventional tillage practices with no-till, conservation tillage or mulch farming.
- Rotating crops and using integrated farming practices.
- Growing cover crops instead of leaving croplands bare in between seasons.
- Using nutrient management instead of chemical fertilizers.
- Integrating croplands with trees and livestock.
- Using integrated pest management techniques instead of heavy pesticide use.
- Replacing surface flood irrigation with furrow, drip or sub-irrigation practices.