by Gifford Hall, Zero Waste Humboldt HSU Intern
Agricultural and forestry practices account for at least 24% of global carbon emissions. Under current management practices, agriculture remains one of the leading contributors to global carbon emissions. The good news is that agriculture is one of the few economic sectors that has the potential to transition from a net carbon emitter to a net carbon sink with specific techniques and practices broadly known as “carbon farming.” These practices contribute to the removal of carbon from the atmosphere, which is sequestered in soil. This method of agriculture has enormous potential for removing greenhouse gases from the atmosphere, a crucial factor of global climate change.
The Carbon Cycle
The carbon cycle is a natural process that fluctuates carbon through five main sources within the planet. Human activity has tipped the balance of the carbon cycle through extracting sequestered carbon as fossil fuels. These dense forms of carbon release carbon dioxide when burned, trapping the sun’s heat and altering the global climate. We have an opportunity to restore balance within the carbon cycle and ameliorate climate change, build resilience to drought and increase our agricultural productivity naturally. This natural solution is called Carbon Farming.
Carbon farming is a broad set of agricultural practices that result in increased storage of atmospheric carbon in soil. Many of these practices are common in organic farming, regenerative agriculture, permaculture, and other approaches to food production. Although most conventional agriculture practices result in the release of carbon, practices classified under carbon farming aim to do the opposite.
There are at least thirty-two on-farm conservation practices that are known to improve soil health and sequester carbon, while producing important co-benefits: increased water retention, hydrological function, biodiversity, and resilience. Here are a few examples of practices that farmers (or even gardeners) can use to help sequester carbon and improve soil health:
- Leftover biomass is returned to the soil as mulch after harvest instead of being removed or burned.
- Conventional tillage practices are replaced by conservation tillage, no till, and/or mulch farming.
- Cover crops are grown during the off-season instead of leaving croplands bare.
- Continuous monocultures are replaced by high diversity crop rotations and integrated farming practices.
- Intensive use of chemical fertilizers is replaced by nutrient management and precision farming.
- Intensive cropping is replaced by croplands integrated with trees and livestock.
- Surface flood irrigation is replaced by drip, furrow, or sub-irrigation.
- The indiscriminate use of pesticides is replaced by integrated pest management techniques.
- Degraded soils are restored to their natural states instead of being used as cropland.
Recent studies demonstrate the efficacy of carbon-beneficial agricultural practices in increasing soil carbon sequestration. Compost use has been shown to increase the amount of carbon stored in both grassland and cropland soils and has important co-benefits, such as increased primary productivity and water-holding capacity.
A group of concerned Redwood Coast residents, climate action and environmental organizations led by Dr. Wendy Ring are currently researching carbon farming to address the growing problem of food waste in Humboldt. To learn more, email zerowastehumboldt@gmail.com .