We humans often have the impression that it is the plants that feed us. It’s not entirely false, but the equation is incomplete… one of the most important and fascinating variables is often left out. This variable is invisible and is under our feet: the ground.
It is the soil that nourishes what nourishes us and is, literally and figuratively, the foundation of our health and our life on Earth. Yet we know so little about him.
On this World Soil Day, we would like to invite you to get to know this living and nourishing heritage, which is home to a quarter of the world’s biodiversity!
A biodiversity “party”
Let’s start with a little Soil Science 101: Mineral soil is made up of approximately 45% mineral particles, 20% air, 30% water and 5% organic matter, and provides nutrients for plants to grow. growth. However, for nutrients to be assimilated by plants, a soil teeming with life is needed, where a diversity of living beings mostly invisible to the naked eye are active.
Living soil is healthy soil where the iconic earthworm is accompanied in its work by woodlice, myriapods, arachnids, ants, springtails, mites, nematodes, protozoa, fungi and bacteria. A non-exhaustive and paying list in Scrabble, but which makes you dizzy! This fauna with exotic names carries out a colossal and essential engineering work for the fertility of a soil: it structures it and aerates it and breaks down the organic matter into assimilable nutrients – nitrogen, phosphorus, potassium, etc. — that plants and animals — including humans — need to survive.
A single gram of soil can contain several million bacteria from thousands of different species, 95% of which have not yet been identified. This shows how much science still has to learn about the biology of living soils.
However, this science is also clear about the state of soils on a global scale: more than 30% of the world’s soils are in poor or very poor condition and this degradation could reduce agricultural production by 10% by 2050. .
Healthy soils, a powerful solution
Faced with the climate and biodiversity crises, it is imperative to implement solutions that will meet the needs of the 10 billion people who will tread the ground by 2050. A proven avenue is to abandon agricultural practices intensive to turn to regenerative practices allowing the full potential of the soil to be used to solve many social, environmental and economic issues in a transversal way.
A healthy soil gains in organic matter and therefore sequesters more CO2, thus becoming a carbon sink to combat climate change. Through the presence of more organic matter and the action of fauna and micro-organisms, the soil also acquires a better structure, which allows it to act like a sponge, that is to say both to have water reserves in case of drought and heat waves, while absorbing heavy rains more easily. The result is a soil that allows agriculture to adapt to climatic extremes, a necessity if we hope to maintain food production.
Soil-regenerative agricultural practices also allow farmers to bet on fertile and productive soil requiring less synthetic fertilizers and pesticides which, in addition to polluting our waterways and risking ending up in our food, are increasingly expensive and the supply of which is uncertain. By moving away from it, we improve the resilience of farms and ensure our food security.
Finally, on the human health side, recent studies show that healthy soil produces more nutritious food containing more minerals, vitamins and organic compounds such as antioxidants, which helps fight malnutrition and chronic diseases.
“We protect what we love, and we love what we know”
A lady recently told us that in certain corners of the world, when an individual leaves to live abroad, he brings with him a little soil from his garden so that, if he is sick, he can make an herbal tea that will restore his usual gut microbiota. An intimacy with the living which has something to surprise us!
Équiterre also intends to make this a key topic during the COP15 on biodiversity in the coming weeks: we absolutely must highlight the strong link between soil biodiversity, the quality of our food and our health.
If we collectively slowly learned to know the soil and to love it, the words of Jacques Cousteau would come true and many of us would go out into the street to protect it. And when we talk about protecting what we love, that means tackling head-on what threatens and ultimately destroys it: urban sprawl and industrial encroachment.
A small miracle with great benefits is constantly taking place under our feet. It is to our advantage to preserve it.
* Co-signatories: Nadine Bachand, analyst at Équiterre; Claudel Pétrin-Desrosiers, physician and lecturer at the University of Montreal; Marie-Élise Samson, assistant professor in soil science at Université Laval; Carole Poliquin, director of the film Hummus