This is The ChangeUnderground

I’m your host, Jon Moore

Decarbonise the Air, Recarbonise the Soil!

Welcome to episode 9 of season 9: The Fundamentals of Regen Ag

We’ve looked at the benefits of regen ag over the past eight episodes with brief references to the “How To” aspects of the practice. In the episode we’ll delve into the practice as well as the theory of Regen Ag.

What is Regenerative Agriculture?

Regen Ag is a methodology that works with Nature rather attempting to force natural systems into an industrial framework. It is based upon observation of nature and assumes we will never have full knowledge of what’s going on. To compensate for this, to some extent, we have the evidence from 3.7 billion years of the evolution of life. A testing ground for best practice on a blue planet at the edge of the milky way. 

The deepest learnings available from observing this testing ground can be summarised in the following four principles:

1. No bare soil
2. Plants and animals coevolved to benefit each other
3. No synthetic chemicals
4. Complexity results in stability

From these develop the “on the ground” practices specific to each locale. Clearly a tropical mountainous sloping piece of land with thin to minimal topsoil will require a different approach to a temperate riverside area with 50 metres of topsoil depth.

Let’s have a look at what goes wrong when we breach the principles.

1. No bare soil
   1. When soils are plant free they are exposed to wind, water and sunlight/heat. This leads to a loss of the topsoil, wind and water erosion, and the direct heating of the sun kills the soil biota. These two effects have the secondary effect of discharging CO2 from the soil as the living biota dies off. These biota are what provide food for the plant life. To replace these, chemical ag adds, well, it adds chemicals, further disrupting the soil chemistry and any remaining soil biota.
   2. Bare soil encourages the arrival of pioneer species. These are characterised by having broad leaves, they cover a large area of soil per plant, they usually have deep taproots for bringing nutrients from subsoil levels to the topsoil and massive numbers of seeds. These evolved to colonise and prepare areas from which glaciers have retreated or landslips have occurred. They have short life cycles to build up organic matter on and in the top spoil as they cycle through their generations.
   3. Keep the soil covered with either a mulch, fallen leaves, straw, hay etc or with a living mulch, clover, cover crop or a cash crop.
2. Plants and animals coevolved to benefit each other
   1. Modern chemical and medication based ag tends to separate plants from animals. Monocultures of plant species, 10,000 acres of wheat, corn or soy as an example which are then harvested and trucked to CAFOs (Confined Animal Feeding Operations) to be fed to the stock warehouse like machine parts. The wastes from the animals are either trucked back to the monocultural fields or more usually dumped in piles near the CAFO to pollute groundwater, creeks, rivers and streams.
   2. Ruminants, cows, goats, sheep and their like evolved to be in tight mobs continually moving across grassland/treed savannahs. The stock consumes the feed, defecates and moves on. This has the effect of hitting the grasses, herbs and legumes hard for a short time before allowing them to regrow for a long period of time. This releases nutrients to soil biota, allowing these to multiply and draw carbon out of the atmosphere and into the soil as solid carbon molecules. In effect to decarbonise the air and recarbonise the soil.
   3. The more species of ruminants and monogastric species, pigs, horses, people that interact across the landscape the more stable it becomes. The multitude of vegetative species, growing, being trampled, consumed and manured leads to a deeper more open soil structure better able to allow the infiltration of water from rainfall events. The groundcover of the vegetation reduces evaporation of surface water, cools the topsoil and provides a mix of nutrients for the grazers/browsers in a virtuous cycle of reinforcing balance. 
   4. Birds tend to follow the ruminants and monogastric species, consuming food sources related to the manures and spreading them across the surface of the soils where they are better and more quickly incorporated into the soil, thereby feeding more soil biota. These soil biota tend to be either bacteria and fungi. The balance between the two varying across time with changes in grazing pressure and rainfall throughout the year.
3. No synthetic chemicals
   1. Given the 3.7 billion years of evolution for life on this planet, it is not surprising that soil biota are distressed, destroyed and disrupted by chemical additives. Be they fertilisers, herbicides, pesticides or fungicides, they are, in evolutionary terms, novel compounds for the soils and their biota to deal with. They do have short term growth benefits on selected crop species but this comes with a Faustian deal. For every year of chemical farming 1% of the topsoil is lost. Converting from chemical to regenerative ag actually regrows topsoils, reversing the damage but maybe never returning soils to the same condition they were prior to agriculture. In colonised landscapes, say here in Australia, cattle and sheep dung will and does have a different effect on soil biota to the many species of marsupial that called our soils home prior to 1788. This holds true across all the “New World” colonised soils.
4. Complexity results in stability
   1. Within a mechanical system, the lower number of moving parts, the more likely the system is to remain stable and to be easily serviced. Think of the difference between a push rod operated side valve single piston engine of the 1930s and a dual overhead cam, 16 valve four cylinder engine of today with electronic controls, emissions monitoring and fuel injectors. The earlier version is a much simpler thing for a person to maintain, the latter requires a workshop with access to hardware and software and a mechanic with much more complex skills than a feeler gauge and an adjusting tool to set the tappets. There are fuel and efficiency gains with the complexity but the system is inherently more unstable due to the layers of technology piled on top of each other and the vehicle with up to date tech can become a listening device and a data vacuum.
   2. Thinking of the bare soil example above, a simple biological system of broadleaf species on nearly bare soil could be wiped away with an adverse rainfall event before the plants had time to establish themselves. The arc of recovery from bare soil to steppe or forest is one of increasing diversity, interconnectedness and complexity of systems. Thinking of the landslip and the Eurasian Steppe, an adverse rainfall event on the steppe could lead to localised flash flooding but the ground cover and the soil would remain mostly intact. On the bare soil, more erosion and loss of nutrients would be the result.
   3. Once we account for the fauna in the system, the cycling of nutrients, the life cycles of the plants and of the soil biota and well as the animals we have a dynamic system in equilibrium across time. Number of animals may rise and fall in response to predation or rainfall variations and vegetative mass will vary with grazing pressures but the system will and in the case of places like the Serengeti and the Eurasian Steppe, has been stable since the end of the Pleistocene and through much of the Holocene until the Industrial Revolution. We can recreate these stable, highly complex, wildly alive ecosystems and they will sustain us, if we let them do their thing.

Conclusion: A Path to Sustainable Agriculture

So long as we keep the four principles:

1. No bare soil
2. Plants and animals coevolved to benefit each other
3. No synthetic chemicals
4. Complexity results in stability

At the forefront of our decision making processes, we can and indeed must decarbonise the air and recarbonise the soil.

I’ll be back next week with episode 10 in season 9, a look to the future.