Definition by Regeneration International in 16 February 2017:
‘It describes farming and grazing practices that, among other benefits, reverse climate change by rebuilding soil organic matter and restoring degraded soil biodiversity – resulting in both carbon drawdown and improving the water cycle.’
(Remark: This definition will continue to evolve as research and practice inform what builds the health of soils, sequesters carbon, and grows more topsoil for future generations.)
Regenerative farming goes beyond organic or sustainable. It does not only focus on ‘not harming the land’ but actually improving it, by understanding, respecting and mimicking the mechanisms of the nature in agriculture. Nowadays, agriculture became undeniably an artificial system aiming to control and monitor the nature, rather than understanding the deep-rooted causes of different symptoms we observe in the field.
To be more concrete, regenerative farming means (i) restoring carbon back to soil through a natural and the greatest process: photosynthesis, and (ii) enriching soil life in terms of the quantities and varieties of microbes, insects and plants.
With healthy soil, farmers can groom plants in a stress-free environment, thus in return, plants give us high quality and nutrient dense food without synthetic chemicals to poison the food and degrading soil. This is beneficial for the farmers when farmers can sell more and better crops; consumers’ community when consumers can enjoy safe, high quality and tastier food; the environment when the farming practices can keep carbon in soil stably and reverse climate change.
There is a well-written overview by Jack Kittredge, highly recommended for everyone who has the ‘power’ to take a regenerative step in agriculture:
Restoration of carbon in soil:
As stated in the project Drawdown, regenerative farming is one the most important chances to put carbon back into the soil.
It is estimated that at least 50% of the carbon in the soil has been released into the atmosphere over the past centuries. While conventional farming today accounts for 30% or more of the total annual global greenhouse gas emission, due to the manufacture of feed, fertilizer and pesticides, transportation, refrigeration, waste disposal, decline of soil organic matter, tillage, etc. It is no doubt that the world needs to review and revise our food production system, particularly in agriculture. In fact, not only can we stop emitting greenhouse gases by changing agriculture practices, we can also sequester carbon in soil! ( Rodale Institute, Regenerative Organic Agriculture and Climate Change: A Down-to-Earth Solution to Global Warming, retrieved from: https://rodaleinstitute.org/assets/WhitePaper.pdf)
In the bright side, the international initiative ‘4per1000’ ( 4 per 1000 initiative: https://www.4p1000.org/
) points out that an annual growth rate of 0.4% (the meaning of 4 per 1000) in the soil carbon stocks would halt the increase of CO2 concentration in the atmosphere. Plants absorb CO2 through photosynthesis to feed the microbes in soil, and when plants die and decompose, soil living organisms transform plants into organic matter, restoring the carbon in soil.
If this carbon level increases by 0.4% in the top 30-40 cm of soils, the annual increase in carbon dioxide (CO2) in the atmosphere would be stopped.
The below video makes an outstanding message:
Here’s a quick glance of ‘4per1000’.
According to Food and Agriculture Organization of the United Nations (FAO), soil can sequester around 20,000 megatonnes of carbon in 25 years, more than 10% of greenhouse gas emission. ( FAO: World’s most comprehensive map showing the amount of carbon stocks in the soil launched, retrieved from: http://www.fao.org/news/story/en/item/1071012/icode/)
Today there are over 40 countries have committed in this initiative, together with a list of international organizations and agricultural scientists, please find the list here.
The practices of achieving this initiative will be explained soon.
Soil Biology- Soil Food Web
Following the above initiative, the only one practical approach to put carbon in soil depends on soil biology.
Frist, we have to acknowledge that soil is alive. It is not only a space like a planting plot for plants to place their root. Soil is full of microorganisms such as bacteria, fungi, algae, protozoa, nematode, and many many other creatures. In a teaspoon of healthy soil, there are more microbes than people on earth. Second, microbes coexist in soil with plants, forming a harmonic status of symbiosis: Plants photosynthesize and make carbohydrates not only for their growth, but also exude a significant amount of these carbohydrates into the soil to feed microbes so that microbes help the plants to growth in exchange. ( Hoorman JJ, Islam R, (2010) Understanding soil Microbes and Nutrient Recycling, Ohio State University Fact Sheet, SAG-16-10, Jones C, (2015) Save Our Soils, Acres USA, retrieved from: http://www.amazingcarbon.com/PDF/Jones_ACRES_USA%20(March2015).pdf)
Microbes are fueled by carbon in soil in the form of organic matter and root exudates. To keep carbon in soil stably and not to be consumed by microbes, HUMUS has to be formed. Humus is built by soil organisms from liquid carbon itself, but not by the decomposition of soil organic matter. There is evidence suggesting that building soil humus is not just a job of adding organic matter to your soil. That will create a thriving microbial community and can make crops flourish. To build long-term carbon, you need to do more.( Meléndrez M, (2014) The Journey to Better Soil Health, unpublished paper presented to the First International Humus Expert’s Meeting, Kaindorf, Austria, January 22 and 23, 2014, Soil Carbon Restoration: Can Biology do the Job?, Retrieved from: http://www.nofamass.org/sites/default/files/2015_White_Paper_web.pdf)
The great diversity and quantity of soil organisms make up the soil food web when they eat and grow.
A food web diagram shows a series of conversions (represented by arrows) of energy and nutrients as one organism eats another.
Soil food web is the knowledge supporting regenerative farming practices, and based on solid science with years of observation of soil life via microscope and practices. For more information, please refer to Dr Elaine Ingham (of Soil Foodweb Inc.), a well-known soil microbiologist, who has a wealth of knowledge from years of intensive research in soil biology. The below websites are recommended to understand the important role of soil food web in the nature:
Some of the benefits of healthy soil food web: ( Benefits of the Soil Foodweb: https://www.permaculturenews.org/files/CompostTeaSpraysBenefitsLivingProof.pdf)
– Retain nutrients including nitrogen, phosphorous, potassium and calcium
– Cycle nutrients into plant available form at the right rates as plants desired
– Build soil structure
– Suppress disease-causing organisms
– Protect plant surfaces
Reclaiming soil health in biological perspective of getting a wide diversity of microbes is the major task for regenerative farmers. There is a lot more to dig deeper in soil science internationally, please stay tune with the above mentioned leading associations and scientists for the updated and thorough explanation of regenerative farming!
Examples of regenerative practices
If you are a farmer, or you have practical experiences of farming, you may wonder how to farm or manage your garden toward a regenerative direction. Please be reminded that the below are some examples suggested from experts from other countries, and we definitely have to adjust according to farm scale, local resources, weather and climate differences, etc. To know more about the progress in The Mushroom Initiative, please visit here.
It is impossible to list out all practices and techniques here, however, there are some important and fundamental examples you can start with:
Start doing your own compost in farm: see the steps of making quality thermal aerated compost here.
No-till/ minimum tillage: as it is one of the most degrading soil practices to break soil aggregation and hyphae of fungi in soil.
Cover crops: choose different locally available species of legumes and deep-rooted grass, cut and mow them before flowering to increase soil carbon. Here is a good article to understand the mechanism of using cover crops.
Keep the soil covered and protected: plants act as a barrier between air and soil, and protecting soil from erosion by wind and water. Most importantly, plants add carbon in soil through photosynthesis, and they are the ‘caretaker’ of soil. ( Andersen, A. B. (2000). Science in agriculture: Advanced methods for sustainable farming. Acres U.S.A.)
Planting perennials: Most of our cash crop in Hong Kong are annuals, however, perennials are beneficial to soil by improving soil structure with minimized soil disturbance and retaining nutrients with their deep root systems. ( Green America: https://www.greenamerica.org/blog/methods-regenerative-agriculture-1)
Diversity and crop rotation: One of the keys to supporting the microbial life in the soil is to promote diversity of plantation. One principle of nature seems to be that the more biodiversity there is in a system, the healthier and more resilient it is. Here is a good reference of crop rotation: https://www.rodalesorganiclife.com/garden/crop-rotation-how-to/slide/3 ( Soil Carbon Restoration: Can Biology do the Job?, Retrieved from: http://www.nofamass.org/sites/default/files/2015_White_Paper_web.pdf)