Soil is the second biggest reservoir of carbon on the planet, next to the oceans. It holds four times more carbon than all the plants and trees in the world. But human activity like deforestation and industrial farming – with its intensive ploughing, monoculture and heavy use of chemical fertilisers and pesticides – is ruining our soils at breakneck speed, killing the organic materials that they contain. Now 40% of agricultural soil is classed as “degraded” or “seriously degraded”. In fact, industrial farming has so damaged our soils that a third of the world’s farmland has been destroyed in the past four decades.
Scientists and farmers around the world are pointing out that we can regenerate degraded soils by switching from intensive industrial farming to more ecological methods – not just organic fertiliser, but also no-tillage, composting, and crop rotation. Soils recover, they not only regain their capacity to hold CO2, they begin to actively pull additional CO2 out of the atmosphere and cooling the planet.
Regenerative farming -- restoring degraded lands -- is one promising option and is being led by International Center for Tropical Agriculture (CIAT) and the World Agroforestry Centre (ICRAF). For example, the 4 parts per 1000 initiative (“4p1000”) aims to increase the carbon stored in the world’s soils by 0.4% per year in order to sequester the human-caused CO2 emissions that are not already absorbed by the land or oceans. Recent analysis shows that 25-50% of this target (equivalent to 0.9-1.85bn tonnes of carbon per year) could be achieved on the 16 million square kilometres of suitable farmland across the world. This would sequester about 6-13% of all CO2 emissions from human activity.
A study published by the US National Academy of Sciences (2018) claims that regenerative farming can sequester 3% of our global carbon emissions. An article in Science suggests it could be up to 15%. Other research suggests sequestration rates could be as high as 40%.
Achieving zero emissions from land use is within reach. We have the methods that can help restore degraded lands and keep lands from being degraded. In doing so, we can simultaneously contribute to global food security and reduce atmospheric carbon emissions.