I recently took the opportunity to go on a short co-op road trip to attend a soil microbiome presentation by Dr Christine Jones. Dr Jones is a soil scientist and microbiologist, which is relevant to us as farmers with an ‘agroecological’, or ‘regenerative’, mindset. Agroecology considers the soil as a living system, and takes a holistic approach to growing with the soil ecology.

Dr Jones began by drawing a comparison between the soil and our guts – both have what we call a ‘microbiome’. That is, a complex ecosystem of microbes that maintains healthy functioning of the broader system. In our case, our bodies. In the case of the soil, the earth and its climate.

Autoimmune diseases have risen from 1 in 1000, to 1 in 42 and are still rising. Infertility rates are also increasing dramatically. There is ample literature in medical science pointing to the impact that our gut microbiome has on our health. Since, different microbes are associated with different nutrients or functions, maintaining our microbiome requires a diversity of plant foods. Dr Jones recommends 30 per day!

Our metabolic processes require enzymes. Enzymes require a catalyst. Catalysts are metals. Therefore, nutritional depletion leads to bodily dysfunction and vulnerability to non-communicable disease. This science is well understood, yet we baulk at the thought of these processes and relationships applying to the soil. The health of the soil microbiome depends on a similar diversity in plant ‘foods’.

Plants send chemical signals into the soil via their roots to attract specific kinds of bacteria. For example, if the plant detects a deficiency in phosphorus (P), it will attract bacteria that can solulise P. These bacteria are then absorbed into the root hairs and metabolised by the plant, however, the DNA of that microbe remains. The DNA is then ejected back into the soil where it reforms a cell wall and becomes bacteria anew!

Why is all of this relevant? 3 reasons.

The plant

Akin to how our gut microbiome fuels our bodies, soil that is overflowing with microbes will produce plants that are verdant and healthy. They will be less susceptible to disease and thus requires less (or no) intervention with poisons.

The soil microbiome is able to metabolise nutrients in the soil and supply these to the plants. The plants are then able to break down atmospheric Nitrogren (a nutrient used for growth), meaning less (or no) intervention with synthetic fertiliser.

Christine Jones nutrient deficiency in vegetables

Nutritional value

Plant foods that are grown in diverse biologically active systems (and by extension, the animals we eat that are raised on these plants) have a high nutritional value. Dan Kitterage, of The Real Food Campaign, conducted an analysis of the nutrient density of a range of carrots. He found that to get the same value of eating the carrot with the most nutritional value, one would have to consume 200 of the carrots with the least.

The productivist approach of ‘big ag’ is failing us on two fronts. Firstly, the idea that a handful of powerful companies can ‘feed the world’ with massive mono-cultural factory farms is negated by the fact that the food produced is devoid of nutrients. It’s like to an ‘inverse square’ relationship. The bigger and more simplified the system, the more is required to reach the same level nutrition.

Secondly, chemical residues on food are deleterious to human health. In spite of any studies suggesting ‘safe levels’ for consumption, if the plants one is consuming do not contain the nutrients to feed our gut microbiome, our ability to metabolise toxins is impaired. Therefore, the bar for ‘safe levels’ of chemicals ingested with food is lowered.

The climate

The sun is the source of all life. Energy from the sun enters the Earth’s atmosphere as light and is converted into other forms of energy. When the light hits the plants, it is transformed into biochemical energy which travels up the food chain to us. This process is an endothermic (cooling) reaction. The light energy is being stored.

Conversely, with an absence of plants, the light hits the ground and is converted and released as heat which causes evaporation and kills the biology in the soil. The only way for that water to nucleate and fall as rain is in the presence of, you guessed it, plants. Healthily functioning plants, with a powerful soil microbiome are the drivers of the Earth’s cooling processes.

Our few hours with Dr Jones meant that we could only scrape the surface of the microbiome story. I was hanging from every single word and hurriedly scrawling notes as she fired off paradigm-smashing facts, statistics and stories from our soils’ past. The take home message for me is that plant diversity and plant cover are paramount in building and maintaining a well-functioning soil microbiome. Microbes run the world and we need to give them the appropriate respect and care.